diff options
Diffstat (limited to 'drivers/gpio/gpiolib.c')
| -rw-r--r-- | drivers/gpio/gpiolib.c | 5466 |
1 files changed, 3092 insertions, 2374 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 1651d7f0a303..91e0c384f34a 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -1,34 +1,45 @@ // SPDX-License-Identifier: GPL-2.0 + +#include <linux/acpi.h> +#include <linux/array_size.h> #include <linux/bitmap.h> -#include <linux/kernel.h> -#include <linux/module.h> +#include <linux/cleanup.h> +#include <linux/compat.h> +#include <linux/debugfs.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/errno.h> +#include <linux/file.h> +#include <linux/fs.h> +#include <linux/idr.h> #include <linux/interrupt.h> #include <linux/irq.h> -#include <linux/spinlock.h> +#include <linux/irqdesc.h> +#include <linux/kernel.h> #include <linux/list.h> -#include <linux/device.h> -#include <linux/err.h> -#include <linux/debugfs.h> +#include <linux/lockdep.h> +#include <linux/module.h> +#include <linux/nospec.h> +#include <linux/of.h> +#include <linux/pinctrl/consumer.h> #include <linux/seq_file.h> -#include <linux/gpio.h> -#include <linux/of_gpio.h> -#include <linux/idr.h> #include <linux/slab.h> -#include <linux/acpi.h> +#include <linux/srcu.h> +#include <linux/string.h> +#include <linux/string_choices.h> + +#include <linux/gpio.h> #include <linux/gpio/driver.h> #include <linux/gpio/machine.h> -#include <linux/pinctrl/consumer.h> -#include <linux/cdev.h> -#include <linux/fs.h> -#include <linux/uaccess.h> -#include <linux/compat.h> -#include <linux/anon_inodes.h> -#include <linux/file.h> -#include <linux/kfifo.h> -#include <linux/poll.h> -#include <linux/timekeeping.h> + #include <uapi/linux/gpio.h> +#include "gpiolib-acpi.h" +#include "gpiolib-cdev.h" +#include "gpiolib-of.h" +#include "gpiolib-shared.h" +#include "gpiolib-swnode.h" +#include "gpiolib-sysfs.h" #include "gpiolib.h" #define CREATE_TRACE_POINTS @@ -41,58 +52,114 @@ * GPIOs can sometimes cost only an instruction or two per bit. */ - -/* When debugging, extend minimal trust to callers and platform code. - * Also emit diagnostic messages that may help initial bringup, when - * board setup or driver bugs are most common. - * - * Otherwise, minimize overhead in what may be bitbanging codepaths. - */ -#ifdef DEBUG -#define extra_checks 1 -#else -#define extra_checks 0 -#endif - /* Device and char device-related information */ static DEFINE_IDA(gpio_ida); static dev_t gpio_devt; #define GPIO_DEV_MAX 256 /* 256 GPIO chip devices supported */ -static struct bus_type gpio_bus_type = { + +static int gpio_bus_match(struct device *dev, const struct device_driver *drv) +{ + struct fwnode_handle *fwnode = dev_fwnode(dev); + + /* + * Only match if the fwnode doesn't already have a proper struct device + * created for it. + */ + if (fwnode && fwnode->dev != dev) + return 0; + return 1; +} + +static const struct bus_type gpio_bus_type = { .name = "gpio", + .match = gpio_bus_match, }; /* - * Number of GPIOs to use for the fast path in set array + * At the end we want all GPIOs to be dynamically allocated from 0. + * However, some legacy drivers still perform fixed allocation. + * Until they are all fixed, leave 0-512 space for them. */ -#define FASTPATH_NGPIO CONFIG_GPIOLIB_FASTPATH_LIMIT +#define GPIO_DYNAMIC_BASE 512 +/* + * Define the maximum of the possible GPIO in the global numberspace. + * While the GPIO base and numbers are positive, we limit it with signed + * maximum as a lot of code is using negative values for special cases. + */ +#define GPIO_DYNAMIC_MAX INT_MAX -/* gpio_lock prevents conflicts during gpio_desc[] table updates. - * While any GPIO is requested, its gpio_chip is not removable; - * each GPIO's "requested" flag serves as a lock and refcount. +/* + * Number of GPIOs to use for the fast path in set array */ -DEFINE_SPINLOCK(gpio_lock); +#define FASTPATH_NGPIO CONFIG_GPIOLIB_FASTPATH_LIMIT static DEFINE_MUTEX(gpio_lookup_lock); static LIST_HEAD(gpio_lookup_list); -LIST_HEAD(gpio_devices); + +static LIST_HEAD(gpio_devices); +/* Protects the GPIO device list against concurrent modifications. */ +static DEFINE_MUTEX(gpio_devices_lock); +/* Ensures coherence during read-only accesses to the list of GPIO devices. */ +DEFINE_STATIC_SRCU(gpio_devices_srcu); static DEFINE_MUTEX(gpio_machine_hogs_mutex); static LIST_HEAD(gpio_machine_hogs); -static void gpiochip_free_hogs(struct gpio_chip *chip); -static int gpiochip_add_irqchip(struct gpio_chip *gpiochip, +const char *const gpio_suffixes[] = { "gpios", "gpio", NULL }; + +static void gpiochip_free_hogs(struct gpio_chip *gc); +static int gpiochip_add_irqchip(struct gpio_chip *gc, struct lock_class_key *lock_key, struct lock_class_key *request_key); -static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip); -static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip); -static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip); +static void gpiochip_irqchip_remove(struct gpio_chip *gc); +static int gpiochip_irqchip_init_hw(struct gpio_chip *gc); +static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc); +static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc); static bool gpiolib_initialized; -static inline void desc_set_label(struct gpio_desc *d, const char *label) +const char *gpiod_get_label(struct gpio_desc *desc) { - d->label = label; + struct gpio_desc_label *label; + unsigned long flags; + + flags = READ_ONCE(desc->flags); + + label = srcu_dereference_check(desc->label, &desc->gdev->desc_srcu, + srcu_read_lock_held(&desc->gdev->desc_srcu)); + + if (test_bit(GPIOD_FLAG_USED_AS_IRQ, &flags)) + return label ? label->str : "interrupt"; + + if (!test_bit(GPIOD_FLAG_REQUESTED, &flags)) + return NULL; + + return label ? label->str : NULL; +} + +static void desc_free_label(struct rcu_head *rh) +{ + kfree(container_of(rh, struct gpio_desc_label, rh)); +} + +static int desc_set_label(struct gpio_desc *desc, const char *label) +{ + struct gpio_desc_label *new = NULL, *old; + + if (label) { + new = kzalloc(struct_size(new, str, strlen(label) + 1), + GFP_KERNEL); + if (!new) + return -ENOMEM; + + strcpy(new->str, label); + } + + old = rcu_replace_pointer(desc->label, new, 1); + if (old) + call_srcu(&desc->gdev->desc_srcu, &old->rh, desc_free_label); + + return 0; } /** @@ -106,47 +173,52 @@ static inline void desc_set_label(struct gpio_desc *d, const char *label) struct gpio_desc *gpio_to_desc(unsigned gpio) { struct gpio_device *gdev; - unsigned long flags; - spin_lock_irqsave(&gpio_lock, flags); - - list_for_each_entry(gdev, &gpio_devices, list) { - if (gdev->base <= gpio && - gdev->base + gdev->ngpio > gpio) { - spin_unlock_irqrestore(&gpio_lock, flags); - return &gdev->descs[gpio - gdev->base]; + scoped_guard(srcu, &gpio_devices_srcu) { + list_for_each_entry_srcu(gdev, &gpio_devices, list, + srcu_read_lock_held(&gpio_devices_srcu)) { + if (gdev->base <= gpio && + gdev->base + gdev->ngpio > gpio) + return &gdev->descs[gpio - gdev->base]; } } - spin_unlock_irqrestore(&gpio_lock, flags); - - if (!gpio_is_valid(gpio)) - WARN(1, "invalid GPIO %d\n", gpio); - return NULL; } EXPORT_SYMBOL_GPL(gpio_to_desc); +/* This function is deprecated and will be removed soon, don't use. */ +struct gpio_desc *gpiochip_get_desc(struct gpio_chip *gc, + unsigned int hwnum) +{ + return gpio_device_get_desc(gc->gpiodev, hwnum); +} + /** - * gpiochip_get_desc - get the GPIO descriptor corresponding to the given - * hardware number for this chip - * @chip: GPIO chip + * gpio_device_get_desc() - get the GPIO descriptor corresponding to the given + * hardware number for this GPIO device + * @gdev: GPIO device to get the descriptor from * @hwnum: hardware number of the GPIO for this chip * * Returns: - * A pointer to the GPIO descriptor or %ERR_PTR(-EINVAL) if no GPIO exists - * in the given chip for the specified hardware number. + * A pointer to the GPIO descriptor or %EINVAL if no GPIO exists in the given + * chip for the specified hardware number or %ENODEV if the underlying chip + * already vanished. + * + * The reference count of struct gpio_device is *NOT* increased like when the + * GPIO is being requested for exclusive usage. It's up to the caller to make + * sure the GPIO device will stay alive together with the descriptor returned + * by this function. */ -struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, - u16 hwnum) +struct gpio_desc * +gpio_device_get_desc(struct gpio_device *gdev, unsigned int hwnum) { - struct gpio_device *gdev = chip->gpiodev; - if (hwnum >= gdev->ngpio) return ERR_PTR(-EINVAL); - return &gdev->descs[hwnum]; + return &gdev->descs[array_index_nospec(hwnum, gdev->ngpio)]; } +EXPORT_SYMBOL_GPL(gpio_device_get_desc); /** * desc_to_gpio - convert a GPIO descriptor to the integer namespace @@ -164,35 +236,131 @@ int desc_to_gpio(const struct gpio_desc *desc) } EXPORT_SYMBOL_GPL(desc_to_gpio); +/** + * gpiod_hwgpio - Return the GPIO number of the passed descriptor relative to + * its chip. + * @desc: GPIO descriptor + * + * Returns: + * Hardware offset of the GPIO represented by the descriptor. + */ +int gpiod_hwgpio(const struct gpio_desc *desc) +{ + return desc - &desc->gdev->descs[0]; +} +EXPORT_SYMBOL_GPL(gpiod_hwgpio); /** * gpiod_to_chip - Return the GPIO chip to which a GPIO descriptor belongs * @desc: descriptor to return the chip of + * + * *DEPRECATED* + * This function is unsafe and should not be used. Using the chip address + * without taking the SRCU read lock may result in dereferencing a dangling + * pointer. + * + * Returns: + * Address of the GPIO chip backing this device. */ struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc) { - if (!desc || !desc->gdev) + if (!desc) return NULL; - return desc->gdev->chip; + + return gpio_device_get_chip(desc->gdev); } EXPORT_SYMBOL_GPL(gpiod_to_chip); +/** + * gpiod_to_gpio_device() - Return the GPIO device to which this descriptor + * belongs. + * @desc: Descriptor for which to return the GPIO device. + * + * This *DOES NOT* increase the reference count of the GPIO device as it's + * expected that the descriptor is requested and the users already holds a + * reference to the device. + * + * Returns: + * Address of the GPIO device owning this descriptor. + */ +struct gpio_device *gpiod_to_gpio_device(struct gpio_desc *desc) +{ + if (!desc) + return NULL; + + return desc->gdev; +} +EXPORT_SYMBOL_GPL(gpiod_to_gpio_device); + +/** + * gpio_device_get_base() - Get the base GPIO number allocated by this device + * @gdev: GPIO device + * + * Returns: + * First GPIO number in the global GPIO numberspace for this device. + */ +int gpio_device_get_base(struct gpio_device *gdev) +{ + return gdev->base; +} +EXPORT_SYMBOL_GPL(gpio_device_get_base); + +/** + * gpio_device_get_label() - Get the label of this GPIO device + * @gdev: GPIO device + * + * Returns: + * Pointer to the string containing the GPIO device label. The string's + * lifetime is tied to that of the underlying GPIO device. + */ +const char *gpio_device_get_label(struct gpio_device *gdev) +{ + return gdev->label; +} +EXPORT_SYMBOL(gpio_device_get_label); + +/** + * gpio_device_get_chip() - Get the gpio_chip implementation of this GPIO device + * @gdev: GPIO device + * + * Returns: + * Address of the GPIO chip backing this device. + * + * *DEPRECATED* + * Until we can get rid of all non-driver users of struct gpio_chip, we must + * provide a way of retrieving the pointer to it from struct gpio_device. This + * is *NOT* safe as the GPIO API is considered to be hot-unpluggable and the + * chip can dissapear at any moment (unlike reference-counted struct + * gpio_device). + * + * Use at your own risk. + */ +struct gpio_chip *gpio_device_get_chip(struct gpio_device *gdev) +{ + return rcu_dereference_check(gdev->chip, 1); +} +EXPORT_SYMBOL_GPL(gpio_device_get_chip); + /* dynamic allocation of GPIOs, e.g. on a hotplugged device */ -static int gpiochip_find_base(int ngpio) +static int gpiochip_find_base_unlocked(u16 ngpio) { + unsigned int base = GPIO_DYNAMIC_BASE; struct gpio_device *gdev; - int base = ARCH_NR_GPIOS - ngpio; - list_for_each_entry_reverse(gdev, &gpio_devices, list) { + list_for_each_entry_srcu(gdev, &gpio_devices, list, + lockdep_is_held(&gpio_devices_lock)) { /* found a free space? */ - if (gdev->base + gdev->ngpio <= base) + if (gdev->base >= base + ngpio) + break; + /* nope, check the space right after the chip */ + base = gdev->base + gdev->ngpio; + if (base < GPIO_DYNAMIC_BASE) + base = GPIO_DYNAMIC_BASE; + if (base > GPIO_DYNAMIC_MAX - ngpio) break; - else - /* nope, check the space right before the chip */ - base = gdev->base - ngpio; } - if (gpio_is_valid(base)) { + if (base <= GPIO_DYNAMIC_MAX - ngpio) { pr_debug("%s: found new base at %d\n", __func__, base); return base; } else { @@ -201,37 +369,123 @@ static int gpiochip_find_base(int ngpio) } } +/* + * This descriptor validation needs to be inserted verbatim into each + * function taking a descriptor, so we need to use a preprocessor + * macro to avoid endless duplication. If the desc is NULL it is an + * optional GPIO and calls should just bail out. + */ +static int validate_desc(const struct gpio_desc *desc, const char *func) +{ + if (!desc) + return 0; + + if (IS_ERR(desc)) { + pr_warn("%s: invalid GPIO (errorpointer: %pe)\n", func, desc); + return PTR_ERR(desc); + } + + return 1; +} + +#define VALIDATE_DESC(desc) do { \ + int __valid = validate_desc(desc, __func__); \ + if (__valid <= 0) \ + return __valid; \ + } while (0) + +#define VALIDATE_DESC_VOID(desc) do { \ + int __valid = validate_desc(desc, __func__); \ + if (__valid <= 0) \ + return; \ + } while (0) + +/** + * gpiod_is_equal() - Check if two GPIO descriptors refer to the same pin. + * @desc: Descriptor to compare. + * @other: The second descriptor to compare against. + * + * Returns: + * True if the descriptors refer to the same physical pin. False otherwise. + */ +bool gpiod_is_equal(const struct gpio_desc *desc, const struct gpio_desc *other) +{ + return validate_desc(desc, __func__) > 0 && + !IS_ERR_OR_NULL(other) && desc == other; +} +EXPORT_SYMBOL_GPL(gpiod_is_equal); + +static int gpiochip_get_direction(struct gpio_chip *gc, unsigned int offset) +{ + int ret; + + lockdep_assert_held(&gc->gpiodev->srcu); + + if (WARN_ON(!gc->get_direction)) + return -EOPNOTSUPP; + + ret = gc->get_direction(gc, offset); + if (ret < 0) + return ret; + + if (ret != GPIO_LINE_DIRECTION_OUT && ret != GPIO_LINE_DIRECTION_IN) + ret = -EBADE; + + return ret; +} + /** * gpiod_get_direction - return the current direction of a GPIO * @desc: GPIO to get the direction of * - * Returns 0 for output, 1 for input, or an error code in case of error. + * Returns: + * 0 for output, 1 for input, or an error code in case of error. * * This function may sleep if gpiod_cansleep() is true. */ int gpiod_get_direction(struct gpio_desc *desc) { - struct gpio_chip *chip; - unsigned offset; - int status; + unsigned long flags; + unsigned int offset; + int ret; + + ret = validate_desc(desc, __func__); + if (ret <= 0) + return -EINVAL; - chip = gpiod_to_chip(desc); - offset = gpio_chip_hwgpio(desc); + CLASS(gpio_chip_guard, guard)(desc); + if (!guard.gc) + return -ENODEV; + + offset = gpiod_hwgpio(desc); + flags = READ_ONCE(desc->flags); + + /* + * Open drain emulation using input mode may incorrectly report + * input here, fix that up. + */ + if (test_bit(GPIOD_FLAG_OPEN_DRAIN, &flags) && + test_bit(GPIOD_FLAG_IS_OUT, &flags)) + return 0; - if (!chip->get_direction) + if (!guard.gc->get_direction) return -ENOTSUPP; - status = chip->get_direction(chip, offset); - if (status > 0) { - /* GPIOF_DIR_IN, or other positive */ - status = 1; - clear_bit(FLAG_IS_OUT, &desc->flags); - } - if (status == 0) { - /* GPIOF_DIR_OUT */ - set_bit(FLAG_IS_OUT, &desc->flags); - } - return status; + ret = gpiochip_get_direction(guard.gc, offset); + if (ret < 0) + return ret; + + /* + * GPIO_LINE_DIRECTION_IN or other positive, + * otherwise GPIO_LINE_DIRECTION_OUT. + */ + if (ret > 0) + ret = 1; + + assign_bit(GPIOD_FLAG_IS_OUT, &flags, !ret); + WRITE_ONCE(desc->flags, flags); + + return ret; } EXPORT_SYMBOL_GPL(gpiod_get_direction); @@ -239,30 +493,32 @@ EXPORT_SYMBOL_GPL(gpiod_get_direction); * Add a new chip to the global chips list, keeping the list of chips sorted * by range(means [base, base + ngpio - 1]) order. * - * Return -EBUSY if the new chip overlaps with some other chip's integer - * space. + * Returns: + * -EBUSY if the new chip overlaps with some other chip's integer space. */ -static int gpiodev_add_to_list(struct gpio_device *gdev) +static int gpiodev_add_to_list_unlocked(struct gpio_device *gdev) { struct gpio_device *prev, *next; + lockdep_assert_held(&gpio_devices_lock); + if (list_empty(&gpio_devices)) { /* initial entry in list */ - list_add_tail(&gdev->list, &gpio_devices); + list_add_tail_rcu(&gdev->list, &gpio_devices); return 0; } - next = list_entry(gpio_devices.next, struct gpio_device, list); + next = list_first_entry(&gpio_devices, struct gpio_device, list); if (gdev->base + gdev->ngpio <= next->base) { /* add before first entry */ - list_add(&gdev->list, &gpio_devices); + list_add_rcu(&gdev->list, &gpio_devices); return 0; } - prev = list_entry(gpio_devices.prev, struct gpio_device, list); + prev = list_last_entry(&gpio_devices, struct gpio_device, list); if (prev->base + prev->ngpio <= gdev->base) { /* add behind last entry */ - list_add_tail(&gdev->list, &gpio_devices); + list_add_tail_rcu(&gdev->list, &gpio_devices); return 0; } @@ -274,60 +530,63 @@ static int gpiodev_add_to_list(struct gpio_device *gdev) /* add between prev and next */ if (prev->base + prev->ngpio <= gdev->base && gdev->base + gdev->ngpio <= next->base) { - list_add(&gdev->list, &prev->list); + list_add_rcu(&gdev->list, &prev->list); return 0; } } - dev_err(&gdev->dev, "GPIO integer space overlap, cannot add chip\n"); + synchronize_srcu(&gpio_devices_srcu); + return -EBUSY; } /* * Convert a GPIO name to its descriptor + * Note that there is no guarantee that GPIO names are globally unique! + * Hence this function will return, if it exists, a reference to the first GPIO + * line found that matches the given name. */ static struct gpio_desc *gpio_name_to_desc(const char * const name) { struct gpio_device *gdev; - unsigned long flags; + struct gpio_desc *desc; + struct gpio_chip *gc; - spin_lock_irqsave(&gpio_lock, flags); + if (!name) + return NULL; - list_for_each_entry(gdev, &gpio_devices, list) { - int i; + guard(srcu)(&gpio_devices_srcu); - for (i = 0; i != gdev->ngpio; ++i) { - struct gpio_desc *desc = &gdev->descs[i]; + list_for_each_entry_srcu(gdev, &gpio_devices, list, + srcu_read_lock_held(&gpio_devices_srcu)) { + guard(srcu)(&gdev->srcu); - if (!desc->name || !name) - continue; + gc = srcu_dereference(gdev->chip, &gdev->srcu); + if (!gc) + continue; - if (!strcmp(desc->name, name)) { - spin_unlock_irqrestore(&gpio_lock, flags); + for_each_gpio_desc(gc, desc) { + if (desc->name && !strcmp(desc->name, name)) return desc; - } } } - spin_unlock_irqrestore(&gpio_lock, flags); - return NULL; } /* - * Takes the names from gc->names and checks if they are all unique. If they - * are, they are assigned to their gpio descriptors. + * Take the names from gc->names and assign them to their GPIO descriptors. + * Warn if a name is already used for a GPIO line on a different GPIO chip. * - * Warning if one of the names is already used for a different GPIO. + * Note that: + * 1. Non-unique names are still accepted, + * 2. Name collisions within the same GPIO chip are not reported. */ -static int gpiochip_set_desc_names(struct gpio_chip *gc) +static void gpiochip_set_desc_names(struct gpio_chip *gc) { struct gpio_device *gdev = gc->gpiodev; int i; - if (!gc->names) - return 0; - /* First check all names if they are unique */ for (i = 0; i != gc->ngpio; ++i) { struct gpio_desc *gpio; @@ -342,916 +601,455 @@ static int gpiochip_set_desc_names(struct gpio_chip *gc) /* Then add all names to the GPIO descriptors */ for (i = 0; i != gc->ngpio; ++i) gdev->descs[i].name = gc->names[i]; - - return 0; } -static unsigned long *gpiochip_allocate_mask(struct gpio_chip *chip) -{ - unsigned long *p; - - p = kmalloc_array(BITS_TO_LONGS(chip->ngpio), sizeof(*p), GFP_KERNEL); - if (!p) - return NULL; - - /* Assume by default all GPIOs are valid */ - bitmap_fill(p, chip->ngpio); - - return p; -} - -static int gpiochip_alloc_valid_mask(struct gpio_chip *gpiochip) +/* + * gpiochip_set_names - Set GPIO line names using device properties + * @chip: GPIO chip whose lines should be named, if possible + * + * Looks for device property "gpio-line-names" and if it exists assigns + * GPIO line names for the chip. The memory allocated for the assigned + * names belong to the underlying firmware node and should not be released + * by the caller. + */ +static int gpiochip_set_names(struct gpio_chip *chip) { -#ifdef CONFIG_OF_GPIO - int size; - struct device_node *np = gpiochip->of_node; + struct gpio_device *gdev = chip->gpiodev; + struct device *dev = &gdev->dev; + const char **names; + int ret, i; + int count; - size = of_property_count_u32_elems(np, "gpio-reserved-ranges"); - if (size > 0 && size % 2 == 0) - gpiochip->need_valid_mask = true; -#endif + count = device_property_string_array_count(dev, "gpio-line-names"); + if (count < 0) + return 0; - if (!gpiochip->need_valid_mask) + /* + * When offset is set in the driver side we assume the driver internally + * is using more than one gpiochip per the same device. We have to stop + * setting friendly names if the specified ones with 'gpio-line-names' + * are less than the offset in the device itself. This means all the + * lines are not present for every single pin within all the internal + * gpiochips. + */ + if (count <= chip->offset) { + dev_warn(dev, "gpio-line-names too short (length %d), cannot map names for the gpiochip at offset %u\n", + count, chip->offset); return 0; + } - gpiochip->valid_mask = gpiochip_allocate_mask(gpiochip); - if (!gpiochip->valid_mask) + names = kcalloc(count, sizeof(*names), GFP_KERNEL); + if (!names) return -ENOMEM; - return 0; -} + ret = device_property_read_string_array(dev, "gpio-line-names", + names, count); + if (ret < 0) { + dev_warn(dev, "failed to read GPIO line names\n"); + kfree(names); + return ret; + } -static int gpiochip_init_valid_mask(struct gpio_chip *gpiochip) -{ - if (gpiochip->init_valid_mask) - return gpiochip->init_valid_mask(gpiochip); + /* + * When more that one gpiochip per device is used, 'count' can + * contain at most number gpiochips x chip->ngpio. We have to + * correctly distribute all defined lines taking into account + * chip->offset as starting point from where we will assign + * the names to pins from the 'names' array. Since property + * 'gpio-line-names' cannot contains gaps, we have to be sure + * we only assign those pins that really exists since chip->ngpio + * can be different of the chip->offset. + */ + count = (count > chip->offset) ? count - chip->offset : count; + if (count > chip->ngpio) + count = chip->ngpio; - return 0; -} + for (i = 0; i < count; i++) { + /* + * Allow overriding "fixed" names provided by the GPIO + * provider. The "fixed" names are more often than not + * generic and less informative than the names given in + * device properties. + */ + if (names[chip->offset + i] && names[chip->offset + i][0]) + gdev->descs[i].name = names[chip->offset + i]; + } -static void gpiochip_free_valid_mask(struct gpio_chip *gpiochip) -{ - kfree(gpiochip->valid_mask); - gpiochip->valid_mask = NULL; -} + kfree(names); -bool gpiochip_line_is_valid(const struct gpio_chip *gpiochip, - unsigned int offset) -{ - /* No mask means all valid */ - if (likely(!gpiochip->valid_mask)) - return true; - return test_bit(offset, gpiochip->valid_mask); + return 0; } -EXPORT_SYMBOL_GPL(gpiochip_line_is_valid); - -/* - * GPIO line handle management - */ -/** - * struct linehandle_state - contains the state of a userspace handle - * @gdev: the GPIO device the handle pertains to - * @label: consumer label used to tag descriptors - * @descs: the GPIO descriptors held by this handle - * @numdescs: the number of descriptors held in the descs array - */ -struct linehandle_state { - struct gpio_device *gdev; - const char *label; - struct gpio_desc *descs[GPIOHANDLES_MAX]; - u32 numdescs; -}; - -#define GPIOHANDLE_REQUEST_VALID_FLAGS \ - (GPIOHANDLE_REQUEST_INPUT | \ - GPIOHANDLE_REQUEST_OUTPUT | \ - GPIOHANDLE_REQUEST_ACTIVE_LOW | \ - GPIOHANDLE_REQUEST_OPEN_DRAIN | \ - GPIOHANDLE_REQUEST_OPEN_SOURCE) - -static long linehandle_ioctl(struct file *filep, unsigned int cmd, - unsigned long arg) +static unsigned long *gpiochip_allocate_mask(struct gpio_chip *gc) { - struct linehandle_state *lh = filep->private_data; - void __user *ip = (void __user *)arg; - struct gpiohandle_data ghd; - DECLARE_BITMAP(vals, GPIOHANDLES_MAX); - int i; - - if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) { - /* NOTE: It's ok to read values of output lines. */ - int ret = gpiod_get_array_value_complex(false, - true, - lh->numdescs, - lh->descs, - NULL, - vals); - if (ret) - return ret; + unsigned long *p; - memset(&ghd, 0, sizeof(ghd)); - for (i = 0; i < lh->numdescs; i++) - ghd.values[i] = test_bit(i, vals); + p = bitmap_alloc(gc->ngpio, GFP_KERNEL); + if (!p) + return NULL; - if (copy_to_user(ip, &ghd, sizeof(ghd))) - return -EFAULT; + /* Assume by default all GPIOs are valid */ + bitmap_fill(p, gc->ngpio); - return 0; - } else if (cmd == GPIOHANDLE_SET_LINE_VALUES_IOCTL) { - /* - * All line descriptors were created at once with the same - * flags so just check if the first one is really output. - */ - if (!test_bit(FLAG_IS_OUT, &lh->descs[0]->flags)) - return -EPERM; - - if (copy_from_user(&ghd, ip, sizeof(ghd))) - return -EFAULT; - - /* Clamp all values to [0,1] */ - for (i = 0; i < lh->numdescs; i++) - __assign_bit(i, vals, ghd.values[i]); - - /* Reuse the array setting function */ - return gpiod_set_array_value_complex(false, - true, - lh->numdescs, - lh->descs, - NULL, - vals); - } - return -EINVAL; + return p; } -#ifdef CONFIG_COMPAT -static long linehandle_ioctl_compat(struct file *filep, unsigned int cmd, - unsigned long arg) +static void gpiochip_free_mask(unsigned long **p) { - return linehandle_ioctl(filep, cmd, (unsigned long)compat_ptr(arg)); + bitmap_free(*p); + *p = NULL; } -#endif -static int linehandle_release(struct inode *inode, struct file *filep) +static unsigned int gpiochip_count_reserved_ranges(struct gpio_chip *gc) { - struct linehandle_state *lh = filep->private_data; - struct gpio_device *gdev = lh->gdev; - int i; + struct device *dev = &gc->gpiodev->dev; + int size; + + /* Format is "start, count, ..." */ + size = device_property_count_u32(dev, "gpio-reserved-ranges"); + if (size > 0 && size % 2 == 0) + return size; - for (i = 0; i < lh->numdescs; i++) - gpiod_free(lh->descs[i]); - kfree(lh->label); - kfree(lh); - put_device(&gdev->dev); return 0; } -static const struct file_operations linehandle_fileops = { - .release = linehandle_release, - .owner = THIS_MODULE, - .llseek = noop_llseek, - .unlocked_ioctl = linehandle_ioctl, -#ifdef CONFIG_COMPAT - .compat_ioctl = linehandle_ioctl_compat, -#endif -}; - -static int linehandle_create(struct gpio_device *gdev, void __user *ip) +static int gpiochip_apply_reserved_ranges(struct gpio_chip *gc) { - struct gpiohandle_request handlereq; - struct linehandle_state *lh; - struct file *file; - int fd, i, count = 0, ret; - u32 lflags; - - if (copy_from_user(&handlereq, ip, sizeof(handlereq))) - return -EFAULT; - if ((handlereq.lines == 0) || (handlereq.lines > GPIOHANDLES_MAX)) - return -EINVAL; - - lflags = handlereq.flags; - - /* Return an error if an unknown flag is set */ - if (lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS) - return -EINVAL; - - /* - * Do not allow OPEN_SOURCE & OPEN_DRAIN flags in a single request. If - * the hardware actually supports enabling both at the same time the - * electrical result would be disastrous. - */ - if ((lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) && - (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)) - return -EINVAL; + struct device *dev = &gc->gpiodev->dev; + unsigned int size; + u32 *ranges; + int ret; - /* OPEN_DRAIN and OPEN_SOURCE flags only make sense for output mode. */ - if (!(lflags & GPIOHANDLE_REQUEST_OUTPUT) && - ((lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) || - (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE))) - return -EINVAL; + size = gpiochip_count_reserved_ranges(gc); + if (size == 0) + return 0; - lh = kzalloc(sizeof(*lh), GFP_KERNEL); - if (!lh) + ranges = kmalloc_array(size, sizeof(*ranges), GFP_KERNEL); + if (!ranges) return -ENOMEM; - lh->gdev = gdev; - get_device(&gdev->dev); - - /* Make sure this is terminated */ - handlereq.consumer_label[sizeof(handlereq.consumer_label)-1] = '\0'; - if (strlen(handlereq.consumer_label)) { - lh->label = kstrdup(handlereq.consumer_label, - GFP_KERNEL); - if (!lh->label) { - ret = -ENOMEM; - goto out_free_lh; - } - } - - /* Request each GPIO */ - for (i = 0; i < handlereq.lines; i++) { - u32 offset = handlereq.lineoffsets[i]; - struct gpio_desc *desc; - - if (offset >= gdev->ngpio) { - ret = -EINVAL; - goto out_free_descs; - } - - desc = &gdev->descs[offset]; - ret = gpiod_request(desc, lh->label); - if (ret) - goto out_free_descs; - lh->descs[i] = desc; - count = i + 1; - - if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW) - set_bit(FLAG_ACTIVE_LOW, &desc->flags); - if (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) - set_bit(FLAG_OPEN_DRAIN, &desc->flags); - if (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE) - set_bit(FLAG_OPEN_SOURCE, &desc->flags); - - ret = gpiod_set_transitory(desc, false); - if (ret < 0) - goto out_free_descs; - /* - * Lines have to be requested explicitly for input - * or output, else the line will be treated "as is". - */ - if (lflags & GPIOHANDLE_REQUEST_OUTPUT) { - int val = !!handlereq.default_values[i]; - - ret = gpiod_direction_output(desc, val); - if (ret) - goto out_free_descs; - } else if (lflags & GPIOHANDLE_REQUEST_INPUT) { - ret = gpiod_direction_input(desc); - if (ret) - goto out_free_descs; - } - dev_dbg(&gdev->dev, "registered chardev handle for line %d\n", - offset); - } - /* Let i point at the last handle */ - i--; - lh->numdescs = handlereq.lines; - - fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC); - if (fd < 0) { - ret = fd; - goto out_free_descs; - } - - file = anon_inode_getfile("gpio-linehandle", - &linehandle_fileops, - lh, - O_RDONLY | O_CLOEXEC); - if (IS_ERR(file)) { - ret = PTR_ERR(file); - goto out_put_unused_fd; + ret = device_property_read_u32_array(dev, "gpio-reserved-ranges", + ranges, size); + if (ret) { + kfree(ranges); + return ret; } - handlereq.fd = fd; - if (copy_to_user(ip, &handlereq, sizeof(handlereq))) { - /* - * fput() will trigger the release() callback, so do not go onto - * the regular error cleanup path here. - */ - fput(file); - put_unused_fd(fd); - return -EFAULT; - } + while (size) { + u32 count = ranges[--size]; + u32 start = ranges[--size]; - fd_install(fd, file); + if (start >= gc->ngpio || start + count > gc->ngpio) + continue; - dev_dbg(&gdev->dev, "registered chardev handle for %d lines\n", - lh->numdescs); + bitmap_clear(gc->gpiodev->valid_mask, start, count); + } + kfree(ranges); return 0; - -out_put_unused_fd: - put_unused_fd(fd); -out_free_descs: - for (i = 0; i < count; i++) - gpiod_free(lh->descs[i]); - kfree(lh->label); -out_free_lh: - kfree(lh); - put_device(&gdev->dev); - return ret; } -/* - * GPIO line event management - */ - -/** - * struct lineevent_state - contains the state of a userspace event - * @gdev: the GPIO device the event pertains to - * @label: consumer label used to tag descriptors - * @desc: the GPIO descriptor held by this event - * @eflags: the event flags this line was requested with - * @irq: the interrupt that trigger in response to events on this GPIO - * @wait: wait queue that handles blocking reads of events - * @events: KFIFO for the GPIO events - * @read_lock: mutex lock to protect reads from colliding with adding - * new events to the FIFO - * @timestamp: cache for the timestamp storing it between hardirq - * and IRQ thread, used to bring the timestamp close to the actual - * event - */ -struct lineevent_state { - struct gpio_device *gdev; - const char *label; - struct gpio_desc *desc; - u32 eflags; - int irq; - wait_queue_head_t wait; - DECLARE_KFIFO(events, struct gpioevent_data, 16); - struct mutex read_lock; - u64 timestamp; -}; - -#define GPIOEVENT_REQUEST_VALID_FLAGS \ - (GPIOEVENT_REQUEST_RISING_EDGE | \ - GPIOEVENT_REQUEST_FALLING_EDGE) - -static __poll_t lineevent_poll(struct file *filep, - struct poll_table_struct *wait) +static int gpiochip_init_valid_mask(struct gpio_chip *gc) { - struct lineevent_state *le = filep->private_data; - __poll_t events = 0; - - poll_wait(filep, &le->wait, wait); - - if (!kfifo_is_empty(&le->events)) - events = EPOLLIN | EPOLLRDNORM; - - return events; -} - - -static ssize_t lineevent_read(struct file *filep, - char __user *buf, - size_t count, - loff_t *f_ps) -{ - struct lineevent_state *le = filep->private_data; - unsigned int copied; int ret; - if (count < sizeof(struct gpioevent_data)) - return -EINVAL; - - do { - if (kfifo_is_empty(&le->events)) { - if (filep->f_flags & O_NONBLOCK) - return -EAGAIN; - - ret = wait_event_interruptible(le->wait, - !kfifo_is_empty(&le->events)); - if (ret) - return ret; - } - - if (mutex_lock_interruptible(&le->read_lock)) - return -ERESTARTSYS; - ret = kfifo_to_user(&le->events, buf, count, &copied); - mutex_unlock(&le->read_lock); + if (!(gpiochip_count_reserved_ranges(gc) || gc->init_valid_mask)) + return 0; - if (ret) - return ret; + gc->gpiodev->valid_mask = gpiochip_allocate_mask(gc); + if (!gc->gpiodev->valid_mask) + return -ENOMEM; - /* - * If we couldn't read anything from the fifo (a different - * thread might have been faster) we either return -EAGAIN if - * the file descriptor is non-blocking, otherwise we go back to - * sleep and wait for more data to arrive. - */ - if (copied == 0 && (filep->f_flags & O_NONBLOCK)) - return -EAGAIN; + ret = gpiochip_apply_reserved_ranges(gc); + if (ret) + return ret; - } while (copied == 0); + if (gc->init_valid_mask) + return gc->init_valid_mask(gc, + gc->gpiodev->valid_mask, + gc->ngpio); - return copied; + return 0; } -static int lineevent_release(struct inode *inode, struct file *filep) +static void gpiochip_free_valid_mask(struct gpio_chip *gc) { - struct lineevent_state *le = filep->private_data; - struct gpio_device *gdev = le->gdev; - - free_irq(le->irq, le); - gpiod_free(le->desc); - kfree(le->label); - kfree(le); - put_device(&gdev->dev); - return 0; + gpiochip_free_mask(&gc->gpiodev->valid_mask); } -static long lineevent_ioctl(struct file *filep, unsigned int cmd, - unsigned long arg) +static int gpiochip_add_pin_ranges(struct gpio_chip *gc) { - struct lineevent_state *le = filep->private_data; - void __user *ip = (void __user *)arg; - struct gpiohandle_data ghd; - /* - * We can get the value for an event line but not set it, - * because it is input by definition. + * Device Tree platforms are supposed to use "gpio-ranges" + * property. This check ensures that the ->add_pin_ranges() + * won't be called for them. */ - if (cmd == GPIOHANDLE_GET_LINE_VALUES_IOCTL) { - int val; - - memset(&ghd, 0, sizeof(ghd)); - - val = gpiod_get_value_cansleep(le->desc); - if (val < 0) - return val; - ghd.values[0] = val; - - if (copy_to_user(ip, &ghd, sizeof(ghd))) - return -EFAULT; - + if (device_property_present(&gc->gpiodev->dev, "gpio-ranges")) return 0; - } - return -EINVAL; -} -#ifdef CONFIG_COMPAT -static long lineevent_ioctl_compat(struct file *filep, unsigned int cmd, - unsigned long arg) -{ - return lineevent_ioctl(filep, cmd, (unsigned long)compat_ptr(arg)); -} -#endif + if (gc->add_pin_ranges) + return gc->add_pin_ranges(gc); -static const struct file_operations lineevent_fileops = { - .release = lineevent_release, - .read = lineevent_read, - .poll = lineevent_poll, - .owner = THIS_MODULE, - .llseek = noop_llseek, - .unlocked_ioctl = lineevent_ioctl, -#ifdef CONFIG_COMPAT - .compat_ioctl = lineevent_ioctl_compat, -#endif -}; + return 0; +} -static irqreturn_t lineevent_irq_thread(int irq, void *p) +/** + * gpiochip_query_valid_mask - return the GPIO validity information + * @gc: gpio chip which validity information is queried + * + * Returns: bitmap representing valid GPIOs or NULL if all GPIOs are valid + * + * Some GPIO chips may support configurations where some of the pins aren't + * available. These chips can have valid_mask set to represent the valid + * GPIOs. This function can be used to retrieve this information. + */ +const unsigned long *gpiochip_query_valid_mask(const struct gpio_chip *gc) { - struct lineevent_state *le = p; - struct gpioevent_data ge; - int ret; - - /* Do not leak kernel stack to userspace */ - memset(&ge, 0, sizeof(ge)); - - ge.timestamp = le->timestamp; - - if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE - && le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) { - int level = gpiod_get_value_cansleep(le->desc); - if (level) - /* Emit low-to-high event */ - ge.id = GPIOEVENT_EVENT_RISING_EDGE; - else - /* Emit high-to-low event */ - ge.id = GPIOEVENT_EVENT_FALLING_EDGE; - } else if (le->eflags & GPIOEVENT_REQUEST_RISING_EDGE) { - /* Emit low-to-high event */ - ge.id = GPIOEVENT_EVENT_RISING_EDGE; - } else if (le->eflags & GPIOEVENT_REQUEST_FALLING_EDGE) { - /* Emit high-to-low event */ - ge.id = GPIOEVENT_EVENT_FALLING_EDGE; - } else { - return IRQ_NONE; - } - - ret = kfifo_put(&le->events, ge); - if (ret != 0) - wake_up_poll(&le->wait, EPOLLIN); - - return IRQ_HANDLED; + return gc->gpiodev->valid_mask; } +EXPORT_SYMBOL_GPL(gpiochip_query_valid_mask); -static irqreturn_t lineevent_irq_handler(int irq, void *p) +bool gpiochip_line_is_valid(const struct gpio_chip *gc, + unsigned int offset) { - struct lineevent_state *le = p; - /* - * Just store the timestamp in hardirq context so we get it as - * close in time as possible to the actual event. + * hog pins are requested before registering GPIO chip */ - le->timestamp = ktime_get_real_ns(); + if (!gc->gpiodev) + return true; - return IRQ_WAKE_THREAD; + /* No mask means all valid */ + if (likely(!gc->gpiodev->valid_mask)) + return true; + return test_bit(offset, gc->gpiodev->valid_mask); } +EXPORT_SYMBOL_GPL(gpiochip_line_is_valid); -static int lineevent_create(struct gpio_device *gdev, void __user *ip) +static void gpiod_free_irqs(struct gpio_desc *desc) { - struct gpioevent_request eventreq; - struct lineevent_state *le; - struct gpio_desc *desc; - struct file *file; - u32 offset; - u32 lflags; - u32 eflags; - int fd; - int ret; - int irqflags = 0; - - if (copy_from_user(&eventreq, ip, sizeof(eventreq))) - return -EFAULT; - - le = kzalloc(sizeof(*le), GFP_KERNEL); - if (!le) - return -ENOMEM; - le->gdev = gdev; - get_device(&gdev->dev); - - /* Make sure this is terminated */ - eventreq.consumer_label[sizeof(eventreq.consumer_label)-1] = '\0'; - if (strlen(eventreq.consumer_label)) { - le->label = kstrdup(eventreq.consumer_label, - GFP_KERNEL); - if (!le->label) { - ret = -ENOMEM; - goto out_free_le; - } - } - - offset = eventreq.lineoffset; - lflags = eventreq.handleflags; - eflags = eventreq.eventflags; - - if (offset >= gdev->ngpio) { - ret = -EINVAL; - goto out_free_label; - } - - /* Return an error if a unknown flag is set */ - if ((lflags & ~GPIOHANDLE_REQUEST_VALID_FLAGS) || - (eflags & ~GPIOEVENT_REQUEST_VALID_FLAGS)) { - ret = -EINVAL; - goto out_free_label; - } - - /* This is just wrong: we don't look for events on output lines */ - if (lflags & GPIOHANDLE_REQUEST_OUTPUT) { - ret = -EINVAL; - goto out_free_label; - } - - desc = &gdev->descs[offset]; - ret = gpiod_request(desc, le->label); - if (ret) - goto out_free_label; - le->desc = desc; - le->eflags = eflags; - - if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW) - set_bit(FLAG_ACTIVE_LOW, &desc->flags); - if (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) - set_bit(FLAG_OPEN_DRAIN, &desc->flags); - if (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE) - set_bit(FLAG_OPEN_SOURCE, &desc->flags); - - ret = gpiod_direction_input(desc); - if (ret) - goto out_free_desc; - - le->irq = gpiod_to_irq(desc); - if (le->irq <= 0) { - ret = -ENODEV; - goto out_free_desc; - } + int irq = gpiod_to_irq(desc); + struct irq_desc *irqd = irq_to_desc(irq); + void *cookie; - if (eflags & GPIOEVENT_REQUEST_RISING_EDGE) - irqflags |= IRQF_TRIGGER_RISING; - if (eflags & GPIOEVENT_REQUEST_FALLING_EDGE) - irqflags |= IRQF_TRIGGER_FALLING; - irqflags |= IRQF_ONESHOT; - - INIT_KFIFO(le->events); - init_waitqueue_head(&le->wait); - mutex_init(&le->read_lock); - - /* Request a thread to read the events */ - ret = request_threaded_irq(le->irq, - lineevent_irq_handler, - lineevent_irq_thread, - irqflags, - le->label, - le); - if (ret) - goto out_free_desc; - - fd = get_unused_fd_flags(O_RDONLY | O_CLOEXEC); - if (fd < 0) { - ret = fd; - goto out_free_irq; - } - - file = anon_inode_getfile("gpio-event", - &lineevent_fileops, - le, - O_RDONLY | O_CLOEXEC); - if (IS_ERR(file)) { - ret = PTR_ERR(file); - goto out_put_unused_fd; - } - - eventreq.fd = fd; - if (copy_to_user(ip, &eventreq, sizeof(eventreq))) { + for (;;) { /* - * fput() will trigger the release() callback, so do not go onto - * the regular error cleanup path here. + * Make sure the action doesn't go away while we're + * dereferencing it. Retrieve and store the cookie value. + * If the irq is freed after we release the lock, that's + * alright - the underlying maple tree lookup will return NULL + * and nothing will happen in free_irq(). */ - fput(file); - put_unused_fd(fd); - return -EFAULT; - } + scoped_guard(mutex, &irqd->request_mutex) { + if (!irq_desc_has_action(irqd)) + return; - fd_install(fd, file); - - return 0; - -out_put_unused_fd: - put_unused_fd(fd); -out_free_irq: - free_irq(le->irq, le); -out_free_desc: - gpiod_free(le->desc); -out_free_label: - kfree(le->label); -out_free_le: - kfree(le); - put_device(&gdev->dev); - return ret; -} - -/* - * gpio_ioctl() - ioctl handler for the GPIO chardev - */ -static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) -{ - struct gpio_device *gdev = filp->private_data; - struct gpio_chip *chip = gdev->chip; - void __user *ip = (void __user *)arg; - - /* We fail any subsequent ioctl():s when the chip is gone */ - if (!chip) - return -ENODEV; - - /* Fill in the struct and pass to userspace */ - if (cmd == GPIO_GET_CHIPINFO_IOCTL) { - struct gpiochip_info chipinfo; - - memset(&chipinfo, 0, sizeof(chipinfo)); - - strncpy(chipinfo.name, dev_name(&gdev->dev), - sizeof(chipinfo.name)); - chipinfo.name[sizeof(chipinfo.name)-1] = '\0'; - strncpy(chipinfo.label, gdev->label, - sizeof(chipinfo.label)); - chipinfo.label[sizeof(chipinfo.label)-1] = '\0'; - chipinfo.lines = gdev->ngpio; - if (copy_to_user(ip, &chipinfo, sizeof(chipinfo))) - return -EFAULT; - return 0; - } else if (cmd == GPIO_GET_LINEINFO_IOCTL) { - struct gpioline_info lineinfo; - struct gpio_desc *desc; - - if (copy_from_user(&lineinfo, ip, sizeof(lineinfo))) - return -EFAULT; - if (lineinfo.line_offset >= gdev->ngpio) - return -EINVAL; - - desc = &gdev->descs[lineinfo.line_offset]; - if (desc->name) { - strncpy(lineinfo.name, desc->name, - sizeof(lineinfo.name)); - lineinfo.name[sizeof(lineinfo.name)-1] = '\0'; - } else { - lineinfo.name[0] = '\0'; - } - if (desc->label) { - strncpy(lineinfo.consumer, desc->label, - sizeof(lineinfo.consumer)); - lineinfo.consumer[sizeof(lineinfo.consumer)-1] = '\0'; - } else { - lineinfo.consumer[0] = '\0'; + cookie = irqd->action->dev_id; } - /* - * Userspace only need to know that the kernel is using - * this GPIO so it can't use it. - */ - lineinfo.flags = 0; - if (test_bit(FLAG_REQUESTED, &desc->flags) || - test_bit(FLAG_IS_HOGGED, &desc->flags) || - test_bit(FLAG_USED_AS_IRQ, &desc->flags) || - test_bit(FLAG_EXPORT, &desc->flags) || - test_bit(FLAG_SYSFS, &desc->flags)) - lineinfo.flags |= GPIOLINE_FLAG_KERNEL; - if (test_bit(FLAG_IS_OUT, &desc->flags)) - lineinfo.flags |= GPIOLINE_FLAG_IS_OUT; - if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) - lineinfo.flags |= GPIOLINE_FLAG_ACTIVE_LOW; - if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) - lineinfo.flags |= GPIOLINE_FLAG_OPEN_DRAIN; - if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) - lineinfo.flags |= GPIOLINE_FLAG_OPEN_SOURCE; - - if (copy_to_user(ip, &lineinfo, sizeof(lineinfo))) - return -EFAULT; - return 0; - } else if (cmd == GPIO_GET_LINEHANDLE_IOCTL) { - return linehandle_create(gdev, ip); - } else if (cmd == GPIO_GET_LINEEVENT_IOCTL) { - return lineevent_create(gdev, ip); + free_irq(irq, cookie); } - return -EINVAL; } -#ifdef CONFIG_COMPAT -static long gpio_ioctl_compat(struct file *filp, unsigned int cmd, - unsigned long arg) -{ - return gpio_ioctl(filp, cmd, (unsigned long)compat_ptr(arg)); -} -#endif - -/** - * gpio_chrdev_open() - open the chardev for ioctl operations - * @inode: inode for this chardev - * @filp: file struct for storing private data - * Returns 0 on success +/* + * The chip is going away but there may be users who had requested interrupts + * on its GPIO lines who have no idea about its removal and have no way of + * being notified about it. We need to free any interrupts still in use here or + * we'll leak memory and resources (like procfs files). */ -static int gpio_chrdev_open(struct inode *inode, struct file *filp) +static void gpiochip_free_remaining_irqs(struct gpio_chip *gc) { - struct gpio_device *gdev = container_of(inode->i_cdev, - struct gpio_device, chrdev); - - /* Fail on open if the backing gpiochip is gone */ - if (!gdev->chip) - return -ENODEV; - get_device(&gdev->dev); - filp->private_data = gdev; + struct gpio_desc *desc; - return nonseekable_open(inode, filp); + for_each_gpio_desc_with_flag(gc, desc, GPIOD_FLAG_USED_AS_IRQ) + gpiod_free_irqs(desc); } -/** - * gpio_chrdev_release() - close chardev after ioctl operations - * @inode: inode for this chardev - * @filp: file struct for storing private data - * Returns 0 on success - */ -static int gpio_chrdev_release(struct inode *inode, struct file *filp) +static void gpiodev_release(struct device *dev) { - struct gpio_device *gdev = container_of(inode->i_cdev, - struct gpio_device, chrdev); - - put_device(&gdev->dev); - return 0; -} - - -static const struct file_operations gpio_fileops = { - .release = gpio_chrdev_release, - .open = gpio_chrdev_open, - .owner = THIS_MODULE, - .llseek = no_llseek, - .unlocked_ioctl = gpio_ioctl, -#ifdef CONFIG_COMPAT - .compat_ioctl = gpio_ioctl_compat, -#endif -}; + struct gpio_device *gdev = to_gpio_device(dev); -static void gpiodevice_release(struct device *dev) -{ - struct gpio_device *gdev = dev_get_drvdata(dev); + /* Call pending kfree()s for descriptor labels. */ + synchronize_srcu(&gdev->desc_srcu); + cleanup_srcu_struct(&gdev->desc_srcu); - list_del(&gdev->list); - ida_simple_remove(&gpio_ida, gdev->id); + ida_free(&gpio_ida, gdev->id); kfree_const(gdev->label); kfree(gdev->descs); + cleanup_srcu_struct(&gdev->srcu); kfree(gdev); } +static const struct device_type gpio_dev_type = { + .name = "gpio_chip", + .release = gpiodev_release, +}; + +#ifdef CONFIG_GPIO_CDEV +#define gcdev_register(gdev, devt) gpiolib_cdev_register((gdev), (devt)) +#define gcdev_unregister(gdev) gpiolib_cdev_unregister((gdev)) +#else +/* + * gpiolib_cdev_register() indirectly calls device_add(), which is still + * required even when cdev is not selected. + */ +#define gcdev_register(gdev, devt) device_add(&(gdev)->dev) +#define gcdev_unregister(gdev) device_del(&(gdev)->dev) +#endif + static int gpiochip_setup_dev(struct gpio_device *gdev) { - int status; + struct fwnode_handle *fwnode = dev_fwnode(&gdev->dev); + int ret; - cdev_init(&gdev->chrdev, &gpio_fileops); - gdev->chrdev.owner = THIS_MODULE; - gdev->dev.devt = MKDEV(MAJOR(gpio_devt), gdev->id); + device_initialize(&gdev->dev); - status = cdev_device_add(&gdev->chrdev, &gdev->dev); - if (status) - return status; + /* + * If fwnode doesn't belong to another device, it's safe to clear its + * initialized flag. + */ + if (fwnode && !fwnode->dev) + fwnode_dev_initialized(fwnode, false); - chip_dbg(gdev->chip, "added GPIO chardev (%d:%d)\n", - MAJOR(gpio_devt), gdev->id); + ret = gcdev_register(gdev, gpio_devt); + if (ret) + return ret; - status = gpiochip_sysfs_register(gdev); - if (status) + ret = gpiochip_sysfs_register(gdev); + if (ret) goto err_remove_device; - /* From this point, the .release() function cleans up gpio_device */ - gdev->dev.release = gpiodevice_release; - pr_debug("%s: registered GPIOs %d to %d on device: %s (%s)\n", - __func__, gdev->base, gdev->base + gdev->ngpio - 1, - dev_name(&gdev->dev), gdev->chip->label ? : "generic"); + dev_dbg(&gdev->dev, "registered GPIOs %u to %u on %s\n", gdev->base, + gdev->base + gdev->ngpio - 1, gdev->label); return 0; err_remove_device: - cdev_device_del(&gdev->chrdev, &gdev->dev); - return status; + gcdev_unregister(gdev); + return ret; } -static void gpiochip_machine_hog(struct gpio_chip *chip, struct gpiod_hog *hog) +static void gpiochip_machine_hog(struct gpio_chip *gc, struct gpiod_hog *hog) { struct gpio_desc *desc; int rv; - desc = gpiochip_get_desc(chip, hog->chip_hwnum); + desc = gpiochip_get_desc(gc, hog->chip_hwnum); if (IS_ERR(desc)) { - pr_err("%s: unable to get GPIO desc: %ld\n", - __func__, PTR_ERR(desc)); + gpiochip_err(gc, "%s: unable to get GPIO desc: %ld\n", + __func__, PTR_ERR(desc)); return; } - if (test_bit(FLAG_IS_HOGGED, &desc->flags)) - return; - rv = gpiod_hog(desc, hog->line_name, hog->lflags, hog->dflags); if (rv) - pr_err("%s: unable to hog GPIO line (%s:%u): %d\n", - __func__, chip->label, hog->chip_hwnum, rv); + gpiod_err(desc, "%s: unable to hog GPIO line (%s:%u): %d\n", + __func__, gc->label, hog->chip_hwnum, rv); } -static void machine_gpiochip_add(struct gpio_chip *chip) +static void machine_gpiochip_add(struct gpio_chip *gc) { struct gpiod_hog *hog; - mutex_lock(&gpio_machine_hogs_mutex); + guard(mutex)(&gpio_machine_hogs_mutex); list_for_each_entry(hog, &gpio_machine_hogs, list) { - if (!strcmp(chip->label, hog->chip_label)) - gpiochip_machine_hog(chip, hog); + if (!strcmp(gc->label, hog->chip_label)) + gpiochip_machine_hog(gc, hog); } - - mutex_unlock(&gpio_machine_hogs_mutex); } static void gpiochip_setup_devs(void) { struct gpio_device *gdev; - int err; + int ret; - list_for_each_entry(gdev, &gpio_devices, list) { - err = gpiochip_setup_dev(gdev); - if (err) - pr_err("%s: Failed to initialize gpio device (%d)\n", - dev_name(&gdev->dev), err); + guard(srcu)(&gpio_devices_srcu); + + list_for_each_entry_srcu(gdev, &gpio_devices, list, + srcu_read_lock_held(&gpio_devices_srcu)) { + ret = gpiochip_setup_dev(gdev); + if (ret) + dev_err(&gdev->dev, + "Failed to initialize gpio device (%d)\n", ret); + } +} + +static void gpiochip_set_data(struct gpio_chip *gc, void *data) +{ + gc->gpiodev->data = data; +} + +/** + * gpiochip_get_data() - get per-subdriver data for the chip + * @gc: GPIO chip + * + * Returns: + * The per-subdriver data for the chip. + */ +void *gpiochip_get_data(struct gpio_chip *gc) +{ + return gc->gpiodev->data; +} +EXPORT_SYMBOL_GPL(gpiochip_get_data); + +/* + * If the calling driver provides the specific firmware node, + * use it. Otherwise use the one from the parent device, if any. + */ +static struct fwnode_handle *gpiochip_choose_fwnode(struct gpio_chip *gc) +{ + if (gc->fwnode) + return gc->fwnode; + + if (gc->parent) + return dev_fwnode(gc->parent); + + return NULL; +} + +int gpiochip_get_ngpios(struct gpio_chip *gc, struct device *dev) +{ + struct fwnode_handle *fwnode = gpiochip_choose_fwnode(gc); + u32 ngpios = gc->ngpio; + int ret; + + if (ngpios == 0) { + ret = fwnode_property_read_u32(fwnode, "ngpios", &ngpios); + if (ret == -ENODATA) + /* + * -ENODATA means that there is no property found and + * we want to issue the error message to the user. + * Besides that, we want to return different error code + * to state that supplied value is not valid. + */ + ngpios = 0; + else if (ret) + return ret; + + gc->ngpio = ngpios; + } + + if (gc->ngpio == 0) { + dev_err(dev, "tried to insert a GPIO chip with zero lines\n"); + return -EINVAL; } + + if (gc->ngpio > FASTPATH_NGPIO) + dev_warn(dev, "line cnt %u is greater than fast path cnt %u\n", + gc->ngpio, FASTPATH_NGPIO); + + return 0; } +EXPORT_SYMBOL_GPL(gpiochip_get_ngpios); -int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data, +int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data, struct lock_class_key *lock_key, struct lock_class_key *request_key) { - unsigned long flags; - int status = 0; - unsigned i; - int base = chip->base; struct gpio_device *gdev; + unsigned int desc_index; + int base = 0; + int ret; /* * First: allocate and populate the internal stat container, and @@ -1260,142 +1058,165 @@ int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data, gdev = kzalloc(sizeof(*gdev), GFP_KERNEL); if (!gdev) return -ENOMEM; + + gdev->dev.type = &gpio_dev_type; gdev->dev.bus = &gpio_bus_type; - gdev->chip = chip; - chip->gpiodev = gdev; - if (chip->parent) { - gdev->dev.parent = chip->parent; - gdev->dev.of_node = chip->parent->of_node; - } + gdev->dev.parent = gc->parent; + rcu_assign_pointer(gdev->chip, gc); -#ifdef CONFIG_OF_GPIO - /* If the gpiochip has an assigned OF node this takes precedence */ - if (chip->of_node) - gdev->dev.of_node = chip->of_node; - else - chip->of_node = gdev->dev.of_node; -#endif + gc->gpiodev = gdev; + gpiochip_set_data(gc, data); + + device_set_node(&gdev->dev, gpiochip_choose_fwnode(gc)); - gdev->id = ida_simple_get(&gpio_ida, 0, 0, GFP_KERNEL); - if (gdev->id < 0) { - status = gdev->id; + ret = ida_alloc(&gpio_ida, GFP_KERNEL); + if (ret < 0) goto err_free_gdev; - } - dev_set_name(&gdev->dev, "gpiochip%d", gdev->id); - device_initialize(&gdev->dev); - dev_set_drvdata(&gdev->dev, gdev); - if (chip->parent && chip->parent->driver) - gdev->owner = chip->parent->driver->owner; - else if (chip->owner) + gdev->id = ret; + + ret = dev_set_name(&gdev->dev, GPIOCHIP_NAME "%d", gdev->id); + if (ret) + goto err_free_ida; + + if (gc->parent && gc->parent->driver) + gdev->owner = gc->parent->driver->owner; + else if (gc->owner) /* TODO: remove chip->owner */ - gdev->owner = chip->owner; + gdev->owner = gc->owner; else gdev->owner = THIS_MODULE; - gdev->descs = kcalloc(chip->ngpio, sizeof(gdev->descs[0]), GFP_KERNEL); + ret = gpiochip_get_ngpios(gc, &gdev->dev); + if (ret) + goto err_free_dev_name; + + gdev->descs = kcalloc(gc->ngpio, sizeof(*gdev->descs), GFP_KERNEL); if (!gdev->descs) { - status = -ENOMEM; - goto err_free_ida; + ret = -ENOMEM; + goto err_free_dev_name; } - if (chip->ngpio == 0) { - chip_err(chip, "tried to insert a GPIO chip with zero lines\n"); - status = -EINVAL; + gdev->label = kstrdup_const(gc->label ?: "unknown", GFP_KERNEL); + if (!gdev->label) { + ret = -ENOMEM; goto err_free_descs; } - if (chip->ngpio > FASTPATH_NGPIO) - chip_warn(chip, "line cnt %u is greater than fast path cnt %u\n", - chip->ngpio, FASTPATH_NGPIO); + gdev->ngpio = gc->ngpio; + gdev->can_sleep = gc->can_sleep; - gdev->label = kstrdup_const(chip->label ?: "unknown", GFP_KERNEL); - if (!gdev->label) { - status = -ENOMEM; - goto err_free_descs; - } + scoped_guard(mutex, &gpio_devices_lock) { + /* + * TODO: this allocates a Linux GPIO number base in the global + * GPIO numberspace for this chip. In the long run we want to + * get *rid* of this numberspace and use only descriptors, but + * it may be a pipe dream. It will not happen before we get rid + * of the sysfs interface anyways. + */ + base = gc->base; + if (base < 0) { + base = gpiochip_find_base_unlocked(gc->ngpio); + if (base < 0) { + ret = base; + base = 0; + goto err_free_label; + } - gdev->ngpio = chip->ngpio; - gdev->data = data; + /* + * TODO: it should not be necessary to reflect the + * assigned base outside of the GPIO subsystem. Go over + * drivers and see if anyone makes use of this, else + * drop this and assign a poison instead. + */ + gc->base = base; + } else { + dev_warn(&gdev->dev, + "Static allocation of GPIO base is deprecated, use dynamic allocation.\n"); + } - spin_lock_irqsave(&gpio_lock, flags); + gdev->base = base; - /* - * TODO: this allocates a Linux GPIO number base in the global - * GPIO numberspace for this chip. In the long run we want to - * get *rid* of this numberspace and use only descriptors, but - * it may be a pipe dream. It will not happen before we get rid - * of the sysfs interface anyways. - */ - if (base < 0) { - base = gpiochip_find_base(chip->ngpio); - if (base < 0) { - status = base; - spin_unlock_irqrestore(&gpio_lock, flags); + ret = gpiodev_add_to_list_unlocked(gdev); + if (ret) { + gpiochip_err(gc, "GPIO integer space overlap, cannot add chip\n"); goto err_free_label; } - /* - * TODO: it should not be necessary to reflect the assigned - * base outside of the GPIO subsystem. Go over drivers and - * see if anyone makes use of this, else drop this and assign - * a poison instead. - */ - chip->base = base; } - gdev->base = base; - status = gpiodev_add_to_list(gdev); - if (status) { - spin_unlock_irqrestore(&gpio_lock, flags); - goto err_free_label; - } + rwlock_init(&gdev->line_state_lock); + RAW_INIT_NOTIFIER_HEAD(&gdev->line_state_notifier); + BLOCKING_INIT_NOTIFIER_HEAD(&gdev->device_notifier); - spin_unlock_irqrestore(&gpio_lock, flags); + ret = init_srcu_struct(&gdev->srcu); + if (ret) + goto err_remove_from_list; - for (i = 0; i < chip->ngpio; i++) - gdev->descs[i].gdev = gdev; + ret = init_srcu_struct(&gdev->desc_srcu); + if (ret) + goto err_cleanup_gdev_srcu; #ifdef CONFIG_PINCTRL INIT_LIST_HEAD(&gdev->pin_ranges); #endif - status = gpiochip_set_desc_names(chip); - if (status) - goto err_remove_from_list; - - status = gpiochip_irqchip_init_valid_mask(chip); - if (status) - goto err_remove_from_list; - - status = gpiochip_alloc_valid_mask(chip); - if (status) - goto err_remove_irqchip_mask; + if (gc->names) + gpiochip_set_desc_names(gc); - status = gpiochip_add_irqchip(chip, lock_key, request_key); - if (status) - goto err_remove_chip; + ret = gpiochip_set_names(gc); + if (ret) + goto err_cleanup_desc_srcu; - status = of_gpiochip_add(chip); - if (status) - goto err_remove_chip; + ret = gpiochip_init_valid_mask(gc); + if (ret) + goto err_cleanup_desc_srcu; - status = gpiochip_init_valid_mask(chip); - if (status) - goto err_remove_chip; + for (desc_index = 0; desc_index < gc->ngpio; desc_index++) { + struct gpio_desc *desc = &gdev->descs[desc_index]; - for (i = 0; i < chip->ngpio; i++) { - struct gpio_desc *desc = &gdev->descs[i]; + desc->gdev = gdev; - if (chip->get_direction && gpiochip_line_is_valid(chip, i)) - desc->flags = !chip->get_direction(chip, i) ? - (1 << FLAG_IS_OUT) : 0; + /* + * We would typically want to use gpiochip_get_direction() here + * but we must not check the return value and bail-out as pin + * controllers can have pins configured to alternate functions + * and return -EINVAL. Also: there's no need to take the SRCU + * lock here. + */ + if (gc->get_direction && gpiochip_line_is_valid(gc, desc_index)) + assign_bit(GPIOD_FLAG_IS_OUT, &desc->flags, + !gc->get_direction(gc, desc_index)); else - desc->flags = !chip->direction_input ? - (1 << FLAG_IS_OUT) : 0; + assign_bit(GPIOD_FLAG_IS_OUT, + &desc->flags, !gc->direction_input); } - acpi_gpiochip_add(chip); + ret = of_gpiochip_add(gc); + if (ret) + goto err_free_valid_mask; + + ret = gpiochip_add_pin_ranges(gc); + if (ret) + goto err_remove_of_chip; + + acpi_gpiochip_add(gc); - machine_gpiochip_add(chip); + machine_gpiochip_add(gc); + + ret = gpiochip_irqchip_init_valid_mask(gc); + if (ret) + goto err_free_hogs; + + ret = gpiochip_irqchip_init_hw(gc); + if (ret) + goto err_remove_irqchip_mask; + + ret = gpiochip_add_irqchip(gc, lock_key, request_key); + if (ret) + goto err_remove_irqchip_mask; + + ret = gpio_device_setup_shared(gdev); + if (ret) + goto err_remove_irqchip; /* * By first adding the chardev, and then adding the device, @@ -1406,93 +1227,94 @@ int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data, * Otherwise, defer until later. */ if (gpiolib_initialized) { - status = gpiochip_setup_dev(gdev); - if (status) - goto err_remove_chip; + ret = gpiochip_setup_dev(gdev); + if (ret) + goto err_teardown_shared; } + return 0; -err_remove_chip: - acpi_gpiochip_remove(chip); - gpiochip_free_hogs(chip); - of_gpiochip_remove(chip); - gpiochip_free_valid_mask(chip); +err_teardown_shared: + gpio_device_teardown_shared(gdev); +err_remove_irqchip: + gpiochip_irqchip_remove(gc); err_remove_irqchip_mask: - gpiochip_irqchip_free_valid_mask(chip); + gpiochip_irqchip_free_valid_mask(gc); +err_free_hogs: + gpiochip_free_hogs(gc); + acpi_gpiochip_remove(gc); + gpiochip_remove_pin_ranges(gc); +err_remove_of_chip: + of_gpiochip_remove(gc); +err_free_valid_mask: + gpiochip_free_valid_mask(gc); +err_cleanup_desc_srcu: + cleanup_srcu_struct(&gdev->desc_srcu); +err_cleanup_gdev_srcu: + cleanup_srcu_struct(&gdev->srcu); err_remove_from_list: - spin_lock_irqsave(&gpio_lock, flags); - list_del(&gdev->list); - spin_unlock_irqrestore(&gpio_lock, flags); + scoped_guard(mutex, &gpio_devices_lock) + list_del_rcu(&gdev->list); + synchronize_srcu(&gpio_devices_srcu); + if (gdev->dev.release) { + /* release() has been registered by gpiochip_setup_dev() */ + gpio_device_put(gdev); + goto err_print_message; + } err_free_label: kfree_const(gdev->label); err_free_descs: kfree(gdev->descs); +err_free_dev_name: + kfree(dev_name(&gdev->dev)); err_free_ida: - ida_simple_remove(&gpio_ida, gdev->id); + ida_free(&gpio_ida, gdev->id); err_free_gdev: - /* failures here can mean systems won't boot... */ - pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__, - gdev->base, gdev->base + gdev->ngpio - 1, - chip->label ? : "generic", status); kfree(gdev); - return status; +err_print_message: + /* failures here can mean systems won't boot... */ + if (ret != -EPROBE_DEFER) { + pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__, + base, base + (int)gc->ngpio - 1, + gc->label ? : "generic", ret); + } + return ret; } EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key); /** - * gpiochip_get_data() - get per-subdriver data for the chip - * @chip: GPIO chip - * - * Returns: - * The per-subdriver data for the chip. - */ -void *gpiochip_get_data(struct gpio_chip *chip) -{ - return chip->gpiodev->data; -} -EXPORT_SYMBOL_GPL(gpiochip_get_data); - -/** * gpiochip_remove() - unregister a gpio_chip - * @chip: the chip to unregister + * @gc: the chip to unregister * * A gpio_chip with any GPIOs still requested may not be removed. */ -void gpiochip_remove(struct gpio_chip *chip) +void gpiochip_remove(struct gpio_chip *gc) { - struct gpio_device *gdev = chip->gpiodev; - struct gpio_desc *desc; - unsigned long flags; - unsigned i; - bool requested = false; + struct gpio_device *gdev = gc->gpiodev; /* FIXME: should the legacy sysfs handling be moved to gpio_device? */ gpiochip_sysfs_unregister(gdev); - gpiochip_free_hogs(chip); + gpiochip_free_hogs(gc); + gpiochip_free_remaining_irqs(gc); + + scoped_guard(mutex, &gpio_devices_lock) + list_del_rcu(&gdev->list); + synchronize_srcu(&gpio_devices_srcu); + /* Numb the device, cancelling all outstanding operations */ - gdev->chip = NULL; - gpiochip_irqchip_remove(chip); - acpi_gpiochip_remove(chip); - gpiochip_remove_pin_ranges(chip); - of_gpiochip_remove(chip); - gpiochip_free_valid_mask(chip); + rcu_assign_pointer(gdev->chip, NULL); + synchronize_srcu(&gdev->srcu); + gpio_device_teardown_shared(gdev); + gpiochip_irqchip_remove(gc); + acpi_gpiochip_remove(gc); + of_gpiochip_remove(gc); + gpiochip_remove_pin_ranges(gc); + gpiochip_free_valid_mask(gc); /* * We accept no more calls into the driver from this point, so - * NULL the driver data pointer + * NULL the driver data pointer. */ - gdev->data = NULL; - - spin_lock_irqsave(&gpio_lock, flags); - for (i = 0; i < gdev->ngpio; i++) { - desc = &gdev->descs[i]; - if (test_bit(FLAG_REQUESTED, &desc->flags)) - requested = true; - } - spin_unlock_irqrestore(&gpio_lock, flags); - - if (requested) - dev_crit(&gdev->dev, - "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n"); + gpiochip_set_data(gc, NULL); /* * The gpiochip side puts its use of the device to rest here: @@ -1500,100 +1322,140 @@ void gpiochip_remove(struct gpio_chip *chip) * be removed, else it will be dangling until the last user is * gone. */ - cdev_device_del(&gdev->chrdev, &gdev->dev); - put_device(&gdev->dev); + gcdev_unregister(gdev); + gpio_device_put(gdev); } EXPORT_SYMBOL_GPL(gpiochip_remove); -static void devm_gpio_chip_release(struct device *dev, void *res) -{ - struct gpio_chip *chip = *(struct gpio_chip **)res; - - gpiochip_remove(chip); -} - /** - * devm_gpiochip_add_data() - Resource manager gpiochip_add_data() - * @dev: pointer to the device that gpio_chip belongs to. - * @chip: the chip to register, with chip->base initialized - * @data: driver-private data associated with this chip + * gpio_device_find() - find a specific GPIO device + * @data: data to pass to match function + * @match: Callback function to check gpio_chip * - * Context: potentially before irqs will work + * Returns: + * New reference to struct gpio_device. * - * The gpio chip automatically be released when the device is unbound. + * Similar to bus_find_device(). It returns a reference to a gpio_device as + * determined by a user supplied @match callback. The callback should return + * 0 if the device doesn't match and non-zero if it does. If the callback + * returns non-zero, this function will return to the caller and not iterate + * over any more gpio_devices. * - * Returns: - * A negative errno if the chip can't be registered, such as because the - * chip->base is invalid or already associated with a different chip. - * Otherwise it returns zero as a success code. + * The callback takes the GPIO chip structure as argument. During the execution + * of the callback function the chip is protected from being freed. TODO: This + * actually has yet to be implemented. + * + * If the function returns non-NULL, the returned reference must be freed by + * the caller using gpio_device_put(). */ -int devm_gpiochip_add_data(struct device *dev, struct gpio_chip *chip, - void *data) +struct gpio_device *gpio_device_find(const void *data, + int (*match)(struct gpio_chip *gc, + const void *data)) { - struct gpio_chip **ptr; - int ret; + struct gpio_device *gdev; + struct gpio_chip *gc; - ptr = devres_alloc(devm_gpio_chip_release, sizeof(*ptr), - GFP_KERNEL); - if (!ptr) - return -ENOMEM; + might_sleep(); - ret = gpiochip_add_data(chip, data); - if (ret < 0) { - devres_free(ptr); - return ret; + guard(srcu)(&gpio_devices_srcu); + + list_for_each_entry_srcu(gdev, &gpio_devices, list, + srcu_read_lock_held(&gpio_devices_srcu)) { + if (!device_is_registered(&gdev->dev)) + continue; + + guard(srcu)(&gdev->srcu); + + gc = srcu_dereference(gdev->chip, &gdev->srcu); + + if (gc && match(gc, data)) + return gpio_device_get(gdev); } - *ptr = chip; - devres_add(dev, ptr); + return NULL; +} +EXPORT_SYMBOL_GPL(gpio_device_find); - return 0; +static int gpio_chip_match_by_label(struct gpio_chip *gc, const void *label) +{ + return gc->label && !strcmp(gc->label, label); } -EXPORT_SYMBOL_GPL(devm_gpiochip_add_data); /** - * gpiochip_find() - iterator for locating a specific gpio_chip - * @data: data to pass to match function - * @match: Callback function to check gpio_chip + * gpio_device_find_by_label() - wrapper around gpio_device_find() finding the + * GPIO device by its backing chip's label + * @label: Label to lookup * - * Similar to bus_find_device. It returns a reference to a gpio_chip as - * determined by a user supplied @match callback. The callback should return - * 0 if the device doesn't match and non-zero if it does. If the callback is - * non-zero, this function will return to the caller and not iterate over any - * more gpio_chips. + * Returns: + * Reference to the GPIO device or NULL. Reference must be released with + * gpio_device_put(). */ -struct gpio_chip *gpiochip_find(void *data, - int (*match)(struct gpio_chip *chip, - void *data)) +struct gpio_device *gpio_device_find_by_label(const char *label) { - struct gpio_device *gdev; - struct gpio_chip *chip = NULL; - unsigned long flags; - - spin_lock_irqsave(&gpio_lock, flags); - list_for_each_entry(gdev, &gpio_devices, list) - if (gdev->chip && match(gdev->chip, data)) { - chip = gdev->chip; - break; - } + return gpio_device_find((void *)label, gpio_chip_match_by_label); +} +EXPORT_SYMBOL_GPL(gpio_device_find_by_label); - spin_unlock_irqrestore(&gpio_lock, flags); +static int gpio_chip_match_by_fwnode(struct gpio_chip *gc, const void *fwnode) +{ + return device_match_fwnode(&gc->gpiodev->dev, fwnode); +} - return chip; +/** + * gpio_device_find_by_fwnode() - wrapper around gpio_device_find() finding + * the GPIO device by its fwnode + * @fwnode: Firmware node to lookup + * + * Returns: + * Reference to the GPIO device or NULL. Reference must be released with + * gpio_device_put(). + */ +struct gpio_device *gpio_device_find_by_fwnode(const struct fwnode_handle *fwnode) +{ + return gpio_device_find((void *)fwnode, gpio_chip_match_by_fwnode); } -EXPORT_SYMBOL_GPL(gpiochip_find); +EXPORT_SYMBOL_GPL(gpio_device_find_by_fwnode); -static int gpiochip_match_name(struct gpio_chip *chip, void *data) +/** + * gpio_device_get() - Increase the reference count of this GPIO device + * @gdev: GPIO device to increase the refcount for + * + * Returns: + * Pointer to @gdev. + */ +struct gpio_device *gpio_device_get(struct gpio_device *gdev) { - const char *name = data; + return to_gpio_device(get_device(&gdev->dev)); +} +EXPORT_SYMBOL_GPL(gpio_device_get); - return !strcmp(chip->label, name); +/** + * gpio_device_put() - Decrease the reference count of this GPIO device and + * possibly free all resources associated with it. + * @gdev: GPIO device to decrease the reference count for + */ +void gpio_device_put(struct gpio_device *gdev) +{ + put_device(&gdev->dev); } +EXPORT_SYMBOL_GPL(gpio_device_put); -static struct gpio_chip *find_chip_by_name(const char *name) +/** + * gpio_device_to_device() - Retrieve the address of the underlying struct + * device. + * @gdev: GPIO device for which to return the address. + * + * This does not increase the reference count of the GPIO device nor the + * underlying struct device. + * + * Returns: + * Address of struct device backing this GPIO device. + */ +struct device *gpio_device_to_device(struct gpio_device *gdev) { - return gpiochip_find((void *)name, gpiochip_match_name); + return &gdev->dev; } +EXPORT_SYMBOL_GPL(gpio_device_to_device); #ifdef CONFIG_GPIOLIB_IRQCHIP @@ -1601,111 +1463,364 @@ static struct gpio_chip *find_chip_by_name(const char *name) * The following is irqchip helper code for gpiochips. */ -static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip) +static int gpiochip_irqchip_init_hw(struct gpio_chip *gc) { - if (!gpiochip->irq.need_valid_mask) + struct gpio_irq_chip *girq = &gc->irq; + + if (!girq->init_hw) return 0; - gpiochip->irq.valid_mask = gpiochip_allocate_mask(gpiochip); - if (!gpiochip->irq.valid_mask) + return girq->init_hw(gc); +} + +static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc) +{ + struct gpio_irq_chip *girq = &gc->irq; + + if (!girq->init_valid_mask) + return 0; + + girq->valid_mask = gpiochip_allocate_mask(gc); + if (!girq->valid_mask) return -ENOMEM; + girq->init_valid_mask(gc, girq->valid_mask, gc->ngpio); + return 0; } -static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip) +static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc) { - kfree(gpiochip->irq.valid_mask); - gpiochip->irq.valid_mask = NULL; + gpiochip_free_mask(&gc->irq.valid_mask); } -bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gpiochip, - unsigned int offset) +static bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gc, + unsigned int offset) { - if (!gpiochip_line_is_valid(gpiochip, offset)) + if (!gpiochip_line_is_valid(gc, offset)) return false; /* No mask means all valid */ - if (likely(!gpiochip->irq.valid_mask)) + if (likely(!gc->irq.valid_mask)) return true; - return test_bit(offset, gpiochip->irq.valid_mask); + return test_bit(offset, gc->irq.valid_mask); } -EXPORT_SYMBOL_GPL(gpiochip_irqchip_irq_valid); + +#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY /** - * gpiochip_set_cascaded_irqchip() - connects a cascaded irqchip to a gpiochip - * @gpiochip: the gpiochip to set the irqchip chain to - * @parent_irq: the irq number corresponding to the parent IRQ for this - * chained irqchip - * @parent_handler: the parent interrupt handler for the accumulated IRQ - * coming out of the gpiochip. If the interrupt is nested rather than - * cascaded, pass NULL in this handler argument + * gpiochip_set_hierarchical_irqchip() - connects a hierarchical irqchip + * to a gpiochip + * @gc: the gpiochip to set the irqchip hierarchical handler to + * @irqchip: the irqchip to handle this level of the hierarchy, the interrupt + * will then percolate up to the parent */ -static void gpiochip_set_cascaded_irqchip(struct gpio_chip *gpiochip, - unsigned int parent_irq, - irq_flow_handler_t parent_handler) +static void gpiochip_set_hierarchical_irqchip(struct gpio_chip *gc, + struct irq_chip *irqchip) { - if (!gpiochip->irq.domain) { - chip_err(gpiochip, "called %s before setting up irqchip\n", - __func__); + /* DT will deal with mapping each IRQ as we go along */ + if (is_of_node(gc->irq.fwnode)) return; - } - if (parent_handler) { - if (gpiochip->can_sleep) { - chip_err(gpiochip, - "you cannot have chained interrupts on a chip that may sleep\n"); - return; + /* + * This is for legacy and boardfile "irqchip" fwnodes: allocate + * irqs upfront instead of dynamically since we don't have the + * dynamic type of allocation that hardware description languages + * provide. Once all GPIO drivers using board files are gone from + * the kernel we can delete this code, but for a transitional period + * it is necessary to keep this around. + */ + if (is_fwnode_irqchip(gc->irq.fwnode)) { + int i; + int ret; + + for (i = 0; i < gc->ngpio; i++) { + struct irq_fwspec fwspec; + unsigned int parent_hwirq; + unsigned int parent_type; + struct gpio_irq_chip *girq = &gc->irq; + + /* + * We call the child to parent translation function + * only to check if the child IRQ is valid or not. + * Just pick the rising edge type here as that is what + * we likely need to support. + */ + ret = girq->child_to_parent_hwirq(gc, i, + IRQ_TYPE_EDGE_RISING, + &parent_hwirq, + &parent_type); + if (ret) { + gpiochip_err(gc, "skip set-up on hwirq %d\n", i); + continue; + } + + fwspec.fwnode = gc->irq.fwnode; + /* This is the hwirq for the GPIO line side of things */ + fwspec.param[0] = girq->child_offset_to_irq(gc, i); + /* Just pick something */ + fwspec.param[1] = IRQ_TYPE_EDGE_RISING; + fwspec.param_count = 2; + ret = irq_domain_alloc_irqs(gc->irq.domain, 1, + NUMA_NO_NODE, &fwspec); + if (ret < 0) { + gpiochip_err(gc, + "can not allocate irq for GPIO line %d parent hwirq %d in hierarchy domain: %d\n", + i, parent_hwirq, ret); + } } - /* - * The parent irqchip is already using the chip_data for this - * irqchip, so our callbacks simply use the handler_data. - */ - irq_set_chained_handler_and_data(parent_irq, parent_handler, - gpiochip); + } + + gpiochip_err(gc, "%s unknown fwnode type proceed anyway\n", __func__); + + return; +} + +static int gpiochip_hierarchy_irq_domain_translate(struct irq_domain *d, + struct irq_fwspec *fwspec, + unsigned long *hwirq, + unsigned int *type) +{ + /* We support standard DT translation */ + if (is_of_node(fwspec->fwnode)) + return irq_domain_translate_twothreecell(d, fwspec, hwirq, type); + + /* This is for board files and others not using DT */ + if (is_fwnode_irqchip(fwspec->fwnode)) { + int ret; + + ret = irq_domain_translate_twocell(d, fwspec, hwirq, type); + if (ret) + return ret; + WARN_ON(*type == IRQ_TYPE_NONE); + return 0; + } + return -EINVAL; +} + +static int gpiochip_hierarchy_irq_domain_alloc(struct irq_domain *d, + unsigned int irq, + unsigned int nr_irqs, + void *data) +{ + struct gpio_chip *gc = d->host_data; + irq_hw_number_t hwirq; + unsigned int type = IRQ_TYPE_NONE; + struct irq_fwspec *fwspec = data; + union gpio_irq_fwspec gpio_parent_fwspec = {}; + unsigned int parent_hwirq; + unsigned int parent_type; + struct gpio_irq_chip *girq = &gc->irq; + int ret; + + /* + * The nr_irqs parameter is always one except for PCI multi-MSI + * so this should not happen. + */ + WARN_ON(nr_irqs != 1); - gpiochip->irq.parent_irq = parent_irq; - gpiochip->irq.parents = &gpiochip->irq.parent_irq; - gpiochip->irq.num_parents = 1; + ret = gc->irq.child_irq_domain_ops.translate(d, fwspec, &hwirq, &type); + if (ret) + return ret; + + gpiochip_dbg(gc, "allocate IRQ %d, hwirq %lu\n", irq, hwirq); + + ret = girq->child_to_parent_hwirq(gc, hwirq, type, + &parent_hwirq, &parent_type); + if (ret) { + gpiochip_err(gc, "can't look up hwirq %lu\n", hwirq); + return ret; } + gpiochip_dbg(gc, "found parent hwirq %u\n", parent_hwirq); + + /* + * We set handle_bad_irq because the .set_type() should + * always be invoked and set the right type of handler. + */ + irq_domain_set_info(d, + irq, + hwirq, + gc->irq.chip, + gc, + girq->handler, + NULL, NULL); + irq_set_probe(irq); + + /* This parent only handles asserted level IRQs */ + ret = girq->populate_parent_alloc_arg(gc, &gpio_parent_fwspec, + parent_hwirq, parent_type); + if (ret) + return ret; + + gpiochip_dbg(gc, "alloc_irqs_parent for %d parent hwirq %d\n", + irq, parent_hwirq); + irq_set_lockdep_class(irq, gc->irq.lock_key, gc->irq.request_key); + ret = irq_domain_alloc_irqs_parent(d, irq, 1, &gpio_parent_fwspec); + /* + * If the parent irqdomain is msi, the interrupts have already + * been allocated, so the EEXIST is good. + */ + if (irq_domain_is_msi(d->parent) && (ret == -EEXIST)) + ret = 0; + if (ret) + gpiochip_err(gc, + "failed to allocate parent hwirq %d for hwirq %lu\n", + parent_hwirq, hwirq); + + return ret; +} + +static unsigned int gpiochip_child_offset_to_irq_noop(struct gpio_chip *gc, + unsigned int offset) +{ + return offset; } /** - * gpiochip_set_chained_irqchip() - connects a chained irqchip to a gpiochip - * @gpiochip: the gpiochip to set the irqchip chain to - * @irqchip: the irqchip to chain to the gpiochip - * @parent_irq: the irq number corresponding to the parent IRQ for this - * chained irqchip - * @parent_handler: the parent interrupt handler for the accumulated IRQ - * coming out of the gpiochip. + * gpiochip_irq_domain_activate() - Lock a GPIO to be used as an IRQ + * @domain: The IRQ domain used by this IRQ chip + * @data: Outermost irq_data associated with the IRQ + * @reserve: If set, only reserve an interrupt vector instead of assigning one + * + * This function is a wrapper that calls gpiochip_lock_as_irq() and is to be + * used as the activate function for the &struct irq_domain_ops. The host_data + * for the IRQ domain must be the &struct gpio_chip. + * + * Returns: + * 0 on success, or negative errno on failure. */ -void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip, - struct irq_chip *irqchip, - unsigned int parent_irq, - irq_flow_handler_t parent_handler) +static int gpiochip_irq_domain_activate(struct irq_domain *domain, + struct irq_data *data, bool reserve) { - if (gpiochip->irq.threaded) { - chip_err(gpiochip, "tried to chain a threaded gpiochip\n"); - return; - } + struct gpio_chip *gc = domain->host_data; + unsigned int hwirq = irqd_to_hwirq(data); - gpiochip_set_cascaded_irqchip(gpiochip, parent_irq, parent_handler); + return gpiochip_lock_as_irq(gc, hwirq); } -EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip); /** - * gpiochip_set_nested_irqchip() - connects a nested irqchip to a gpiochip - * @gpiochip: the gpiochip to set the irqchip nested handler to - * @irqchip: the irqchip to nest to the gpiochip - * @parent_irq: the irq number corresponding to the parent IRQ for this - * nested irqchip + * gpiochip_irq_domain_deactivate() - Unlock a GPIO used as an IRQ + * @domain: The IRQ domain used by this IRQ chip + * @data: Outermost irq_data associated with the IRQ + * + * This function is a wrapper that will call gpiochip_unlock_as_irq() and is to + * be used as the deactivate function for the &struct irq_domain_ops. The + * host_data for the IRQ domain must be the &struct gpio_chip. */ -void gpiochip_set_nested_irqchip(struct gpio_chip *gpiochip, - struct irq_chip *irqchip, - unsigned int parent_irq) +static void gpiochip_irq_domain_deactivate(struct irq_domain *domain, + struct irq_data *data) +{ + struct gpio_chip *gc = domain->host_data; + unsigned int hwirq = irqd_to_hwirq(data); + + return gpiochip_unlock_as_irq(gc, hwirq); +} + +static void gpiochip_hierarchy_setup_domain_ops(struct irq_domain_ops *ops) +{ + ops->activate = gpiochip_irq_domain_activate; + ops->deactivate = gpiochip_irq_domain_deactivate; + ops->alloc = gpiochip_hierarchy_irq_domain_alloc; + + /* + * We only allow overriding the translate() and free() functions for + * hierarchical chips, and this should only be done if the user + * really need something other than 1:1 translation for translate() + * callback and free if user wants to free up any resources which + * were allocated during callbacks, for example populate_parent_alloc_arg. + */ + if (!ops->translate) + ops->translate = gpiochip_hierarchy_irq_domain_translate; + if (!ops->free) + ops->free = irq_domain_free_irqs_common; +} + +static struct irq_domain *gpiochip_hierarchy_create_domain(struct gpio_chip *gc) +{ + struct irq_domain *domain; + + if (!gc->irq.child_to_parent_hwirq || + !gc->irq.fwnode) { + gpiochip_err(gc, "missing irqdomain vital data\n"); + return ERR_PTR(-EINVAL); + } + + if (!gc->irq.child_offset_to_irq) + gc->irq.child_offset_to_irq = gpiochip_child_offset_to_irq_noop; + + if (!gc->irq.populate_parent_alloc_arg) + gc->irq.populate_parent_alloc_arg = + gpiochip_populate_parent_fwspec_twocell; + + gpiochip_hierarchy_setup_domain_ops(&gc->irq.child_irq_domain_ops); + + domain = irq_domain_create_hierarchy( + gc->irq.parent_domain, + 0, + gc->ngpio, + gc->irq.fwnode, + &gc->irq.child_irq_domain_ops, + gc); + + if (!domain) + return ERR_PTR(-ENOMEM); + + gpiochip_set_hierarchical_irqchip(gc, gc->irq.chip); + + return domain; +} + +static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc) +{ + return !!gc->irq.parent_domain; +} + +int gpiochip_populate_parent_fwspec_twocell(struct gpio_chip *gc, + union gpio_irq_fwspec *gfwspec, + unsigned int parent_hwirq, + unsigned int parent_type) { - gpiochip_set_cascaded_irqchip(gpiochip, parent_irq, NULL); + struct irq_fwspec *fwspec = &gfwspec->fwspec; + + fwspec->fwnode = gc->irq.parent_domain->fwnode; + fwspec->param_count = 2; + fwspec->param[0] = parent_hwirq; + fwspec->param[1] = parent_type; + + return 0; } -EXPORT_SYMBOL_GPL(gpiochip_set_nested_irqchip); +EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_twocell); + +int gpiochip_populate_parent_fwspec_fourcell(struct gpio_chip *gc, + union gpio_irq_fwspec *gfwspec, + unsigned int parent_hwirq, + unsigned int parent_type) +{ + struct irq_fwspec *fwspec = &gfwspec->fwspec; + + fwspec->fwnode = gc->irq.parent_domain->fwnode; + fwspec->param_count = 4; + fwspec->param[0] = 0; + fwspec->param[1] = parent_hwirq; + fwspec->param[2] = 0; + fwspec->param[3] = parent_type; + + return 0; +} +EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_fourcell); + +#else + +static struct irq_domain *gpiochip_hierarchy_create_domain(struct gpio_chip *gc) +{ + return ERR_PTR(-EINVAL); +} + +static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc) +{ + return false; +} + +#endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */ /** * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip @@ -1716,231 +1831,350 @@ EXPORT_SYMBOL_GPL(gpiochip_set_nested_irqchip); * This function will set up the mapping for a certain IRQ line on a * gpiochip by assigning the gpiochip as chip data, and using the irqchip * stored inside the gpiochip. + * + * Returns: + * 0 on success, or negative errno on failure. */ -int gpiochip_irq_map(struct irq_domain *d, unsigned int irq, - irq_hw_number_t hwirq) +static int gpiochip_irq_map(struct irq_domain *d, unsigned int irq, + irq_hw_number_t hwirq) { - struct gpio_chip *chip = d->host_data; - int err = 0; + struct gpio_chip *gc = d->host_data; + int ret = 0; - if (!gpiochip_irqchip_irq_valid(chip, hwirq)) + if (!gpiochip_irqchip_irq_valid(gc, hwirq)) return -ENXIO; - irq_set_chip_data(irq, chip); + irq_set_chip_data(irq, gc); /* * This lock class tells lockdep that GPIO irqs are in a different * category than their parents, so it won't report false recursion. */ - irq_set_lockdep_class(irq, chip->irq.lock_key, chip->irq.request_key); - irq_set_chip_and_handler(irq, chip->irq.chip, chip->irq.handler); + irq_set_lockdep_class(irq, gc->irq.lock_key, gc->irq.request_key); + irq_set_chip_and_handler(irq, gc->irq.chip, gc->irq.handler); /* Chips that use nested thread handlers have them marked */ - if (chip->irq.threaded) + if (gc->irq.threaded) irq_set_nested_thread(irq, 1); irq_set_noprobe(irq); - if (chip->irq.num_parents == 1) - err = irq_set_parent(irq, chip->irq.parents[0]); - else if (chip->irq.map) - err = irq_set_parent(irq, chip->irq.map[hwirq]); + if (gc->irq.num_parents == 1) + ret = irq_set_parent(irq, gc->irq.parents[0]); + else if (gc->irq.map) + ret = irq_set_parent(irq, gc->irq.map[hwirq]); - if (err < 0) - return err; + if (ret < 0) + return ret; /* * No set-up of the hardware will happen if IRQ_TYPE_NONE * is passed as default type. */ - if (chip->irq.default_type != IRQ_TYPE_NONE) - irq_set_irq_type(irq, chip->irq.default_type); + if (gc->irq.default_type != IRQ_TYPE_NONE) + irq_set_irq_type(irq, gc->irq.default_type); return 0; } -EXPORT_SYMBOL_GPL(gpiochip_irq_map); -void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq) +static void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq) { - struct gpio_chip *chip = d->host_data; + struct gpio_chip *gc = d->host_data; - if (chip->irq.threaded) + if (gc->irq.threaded) irq_set_nested_thread(irq, 0); irq_set_chip_and_handler(irq, NULL, NULL); irq_set_chip_data(irq, NULL); } -EXPORT_SYMBOL_GPL(gpiochip_irq_unmap); + +static int gpiochip_irq_select(struct irq_domain *d, struct irq_fwspec *fwspec, + enum irq_domain_bus_token bus_token) +{ + struct fwnode_handle *fwnode = fwspec->fwnode; + struct gpio_chip *gc = d->host_data; + unsigned int index = fwspec->param[0]; + + if (fwspec->param_count == 3 && is_of_node(fwnode)) + return of_gpiochip_instance_match(gc, index); + + /* Fallback for twocells */ + return (fwnode && (d->fwnode == fwnode) && (d->bus_token == bus_token)); +} static const struct irq_domain_ops gpiochip_domain_ops = { .map = gpiochip_irq_map, .unmap = gpiochip_irq_unmap, + .select = gpiochip_irq_select, /* Virtually all GPIO irqchips are twocell:ed */ - .xlate = irq_domain_xlate_twocell, + .xlate = irq_domain_xlate_twothreecell, }; -static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset) +static struct irq_domain *gpiochip_simple_create_domain(struct gpio_chip *gc) +{ + struct fwnode_handle *fwnode = dev_fwnode(&gc->gpiodev->dev); + struct irq_domain *domain; + + domain = irq_domain_create_simple(fwnode, gc->ngpio, gc->irq.first, + &gpiochip_domain_ops, gc); + if (!domain) + return ERR_PTR(-EINVAL); + + return domain; +} + +static int gpiochip_to_irq(struct gpio_chip *gc, unsigned int offset) { - if (!gpiochip_irqchip_irq_valid(chip, offset)) + struct irq_domain *domain = gc->irq.domain; + + /* + * Avoid race condition with other code, which tries to lookup + * an IRQ before the irqchip has been properly registered, + * i.e. while gpiochip is still being brought up. + */ + if (!gc->irq.initialized) + return -EPROBE_DEFER; + + if (!gpiochip_irqchip_irq_valid(gc, offset)) return -ENXIO; - return irq_create_mapping(chip->irq.domain, offset); +#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY + if (irq_domain_is_hierarchy(domain)) { + struct irq_fwspec spec; + + spec.fwnode = domain->fwnode; + spec.param_count = 2; + spec.param[0] = gc->irq.child_offset_to_irq(gc, offset); + spec.param[1] = IRQ_TYPE_NONE; + + return irq_create_fwspec_mapping(&spec); + } +#endif + + return irq_create_mapping(domain, offset); +} + +int gpiochip_irq_reqres(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + unsigned int hwirq = irqd_to_hwirq(d); + + return gpiochip_reqres_irq(gc, hwirq); } +EXPORT_SYMBOL(gpiochip_irq_reqres); -static int gpiochip_irq_reqres(struct irq_data *d) +void gpiochip_irq_relres(struct irq_data *d) { - struct gpio_chip *chip = irq_data_get_irq_chip_data(d); + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + unsigned int hwirq = irqd_to_hwirq(d); - return gpiochip_reqres_irq(chip, d->hwirq); + gpiochip_relres_irq(gc, hwirq); } +EXPORT_SYMBOL(gpiochip_irq_relres); -static void gpiochip_irq_relres(struct irq_data *d) +static void gpiochip_irq_mask(struct irq_data *d) { - struct gpio_chip *chip = irq_data_get_irq_chip_data(d); + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + unsigned int hwirq = irqd_to_hwirq(d); - gpiochip_relres_irq(chip, d->hwirq); + if (gc->irq.irq_mask) + gc->irq.irq_mask(d); + gpiochip_disable_irq(gc, hwirq); +} + +static void gpiochip_irq_unmask(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + unsigned int hwirq = irqd_to_hwirq(d); + + gpiochip_enable_irq(gc, hwirq); + if (gc->irq.irq_unmask) + gc->irq.irq_unmask(d); } static void gpiochip_irq_enable(struct irq_data *d) { - struct gpio_chip *chip = irq_data_get_irq_chip_data(d); + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + unsigned int hwirq = irqd_to_hwirq(d); - gpiochip_enable_irq(chip, d->hwirq); - if (chip->irq.irq_enable) - chip->irq.irq_enable(d); - else - chip->irq.chip->irq_unmask(d); + gpiochip_enable_irq(gc, hwirq); + gc->irq.irq_enable(d); } static void gpiochip_irq_disable(struct irq_data *d) { - struct gpio_chip *chip = irq_data_get_irq_chip_data(d); + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + unsigned int hwirq = irqd_to_hwirq(d); - if (chip->irq.irq_disable) - chip->irq.irq_disable(d); - else - chip->irq.chip->irq_mask(d); - gpiochip_disable_irq(chip, d->hwirq); + gc->irq.irq_disable(d); + gpiochip_disable_irq(gc, hwirq); } -static void gpiochip_set_irq_hooks(struct gpio_chip *gpiochip) +static void gpiochip_set_irq_hooks(struct gpio_chip *gc) { - struct irq_chip *irqchip = gpiochip->irq.chip; + struct irq_chip *irqchip = gc->irq.chip; + + if (irqchip->flags & IRQCHIP_IMMUTABLE) + return; + + gpiochip_warn(gc, "not an immutable chip, please consider fixing it!\n"); if (!irqchip->irq_request_resources && !irqchip->irq_release_resources) { irqchip->irq_request_resources = gpiochip_irq_reqres; irqchip->irq_release_resources = gpiochip_irq_relres; } - if (WARN_ON(gpiochip->irq.irq_enable)) + if (WARN_ON(gc->irq.irq_enable)) return; /* Check if the irqchip already has this hook... */ - if (irqchip->irq_enable == gpiochip_irq_enable) { + if (irqchip->irq_enable == gpiochip_irq_enable || + irqchip->irq_mask == gpiochip_irq_mask) { /* * ...and if so, give a gentle warning that this is bad * practice. */ - chip_info(gpiochip, - "detected irqchip that is shared with multiple gpiochips: please fix the driver.\n"); + gpiochip_info(gc, + "detected irqchip that is shared with multiple gpiochips: please fix the driver.\n"); return; } - gpiochip->irq.irq_enable = irqchip->irq_enable; - gpiochip->irq.irq_disable = irqchip->irq_disable; - irqchip->irq_enable = gpiochip_irq_enable; - irqchip->irq_disable = gpiochip_irq_disable; + + if (irqchip->irq_disable) { + gc->irq.irq_disable = irqchip->irq_disable; + irqchip->irq_disable = gpiochip_irq_disable; + } else { + gc->irq.irq_mask = irqchip->irq_mask; + irqchip->irq_mask = gpiochip_irq_mask; + } + + if (irqchip->irq_enable) { + gc->irq.irq_enable = irqchip->irq_enable; + irqchip->irq_enable = gpiochip_irq_enable; + } else { + gc->irq.irq_unmask = irqchip->irq_unmask; + irqchip->irq_unmask = gpiochip_irq_unmask; + } +} + +static int gpiochip_irqchip_add_allocated_domain(struct gpio_chip *gc, + struct irq_domain *domain, + bool allocated_externally) +{ + if (!domain) + return -EINVAL; + + if (gc->to_irq) + gpiochip_warn(gc, "to_irq is redefined in %s and you shouldn't rely on it\n", + __func__); + + gc->to_irq = gpiochip_to_irq; + gc->irq.domain = domain; + gc->irq.domain_is_allocated_externally = allocated_externally; + + /* + * Using barrier() here to prevent compiler from reordering + * gc->irq.initialized before adding irqdomain. + */ + barrier(); + + gc->irq.initialized = true; + + return 0; } /** * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip - * @gpiochip: the GPIO chip to add the IRQ chip to + * @gc: the GPIO chip to add the IRQ chip to * @lock_key: lockdep class for IRQ lock * @request_key: lockdep class for IRQ request + * + * Returns: + * 0 on success, or a negative errno on failure. */ -static int gpiochip_add_irqchip(struct gpio_chip *gpiochip, +static int gpiochip_add_irqchip(struct gpio_chip *gc, struct lock_class_key *lock_key, struct lock_class_key *request_key) { - struct irq_chip *irqchip = gpiochip->irq.chip; - const struct irq_domain_ops *ops; - struct device_node *np; + struct fwnode_handle *fwnode = dev_fwnode(&gc->gpiodev->dev); + struct irq_chip *irqchip = gc->irq.chip; + struct irq_domain *domain; unsigned int type; unsigned int i; + int ret; if (!irqchip) return 0; - if (gpiochip->irq.parent_handler && gpiochip->can_sleep) { - chip_err(gpiochip, "you cannot have chained interrupts on a chip that may sleep\n"); + if (gc->irq.parent_handler && gc->can_sleep) { + gpiochip_err(gc, "you cannot have chained interrupts on a chip that may sleep\n"); return -EINVAL; } - np = gpiochip->gpiodev->dev.of_node; - type = gpiochip->irq.default_type; + type = gc->irq.default_type; /* * Specifying a default trigger is a terrible idea if DT or ACPI is * used to configure the interrupts, as you may end up with * conflicting triggers. Tell the user, and reset to NONE. */ - if (WARN(np && type != IRQ_TYPE_NONE, - "%s: Ignoring %u default trigger\n", np->full_name, type)) + if (WARN(fwnode && type != IRQ_TYPE_NONE, + "%pfw: Ignoring %u default trigger\n", fwnode, type)) type = IRQ_TYPE_NONE; - if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) { - acpi_handle_warn(ACPI_HANDLE(gpiochip->parent), - "Ignoring %u default trigger\n", type); - type = IRQ_TYPE_NONE; - } - - gpiochip->to_irq = gpiochip_to_irq; - gpiochip->irq.default_type = type; - gpiochip->irq.lock_key = lock_key; - gpiochip->irq.request_key = request_key; + gc->irq.default_type = type; + gc->irq.lock_key = lock_key; + gc->irq.request_key = request_key; - if (gpiochip->irq.domain_ops) - ops = gpiochip->irq.domain_ops; - else - ops = &gpiochip_domain_ops; + /* If a parent irqdomain is provided, let's build a hierarchy */ + if (gpiochip_hierarchy_is_hierarchical(gc)) { + domain = gpiochip_hierarchy_create_domain(gc); + } else { + domain = gpiochip_simple_create_domain(gc); + } + if (IS_ERR(domain)) + return PTR_ERR(domain); - gpiochip->irq.domain = irq_domain_add_simple(np, gpiochip->ngpio, - gpiochip->irq.first, - ops, gpiochip); - if (!gpiochip->irq.domain) - return -EINVAL; + if (gc->irq.parent_handler) { + for (i = 0; i < gc->irq.num_parents; i++) { + void *data; - if (gpiochip->irq.parent_handler) { - void *data = gpiochip->irq.parent_handler_data ?: gpiochip; + if (gc->irq.per_parent_data) + data = gc->irq.parent_handler_data_array[i]; + else + data = gc->irq.parent_handler_data ?: gc; - for (i = 0; i < gpiochip->irq.num_parents; i++) { /* * The parent IRQ chip is already using the chip_data * for this IRQ chip, so our callbacks simply use the * handler_data. */ - irq_set_chained_handler_and_data(gpiochip->irq.parents[i], - gpiochip->irq.parent_handler, + irq_set_chained_handler_and_data(gc->irq.parents[i], + gc->irq.parent_handler, data); } } - gpiochip_set_irq_hooks(gpiochip); + gpiochip_set_irq_hooks(gc); - acpi_gpiochip_request_interrupts(gpiochip); + ret = gpiochip_irqchip_add_allocated_domain(gc, domain, false); + if (ret) + return ret; + + acpi_gpiochip_request_interrupts(gc); return 0; } /** * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip - * @gpiochip: the gpiochip to remove the irqchip from + * @gc: the gpiochip to remove the irqchip from * * This is called only from gpiochip_remove() */ -static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) +static void gpiochip_irqchip_remove(struct gpio_chip *gc) { - struct irq_chip *irqchip = gpiochip->irq.chip; + struct irq_chip *irqchip = gc->irq.chip; unsigned int offset; - acpi_gpiochip_free_interrupts(gpiochip); + acpi_gpiochip_free_interrupts(gc); - if (irqchip && gpiochip->irq.parent_handler) { - struct gpio_irq_chip *irq = &gpiochip->irq; + if (irqchip && gc->irq.parent_handler) { + struct gpio_irq_chip *irq = &gc->irq; unsigned int i; for (i = 0; i < irq->num_parents; i++) @@ -1949,180 +2183,131 @@ static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) } /* Remove all IRQ mappings and delete the domain */ - if (gpiochip->irq.domain) { + if (!gc->irq.domain_is_allocated_externally && gc->irq.domain) { unsigned int irq; - for (offset = 0; offset < gpiochip->ngpio; offset++) { - if (!gpiochip_irqchip_irq_valid(gpiochip, offset)) + for (offset = 0; offset < gc->ngpio; offset++) { + if (!gpiochip_irqchip_irq_valid(gc, offset)) continue; - irq = irq_find_mapping(gpiochip->irq.domain, offset); + irq = irq_find_mapping(gc->irq.domain, offset); irq_dispose_mapping(irq); } - irq_domain_remove(gpiochip->irq.domain); + irq_domain_remove(gc->irq.domain); } - if (irqchip) { + if (irqchip && !(irqchip->flags & IRQCHIP_IMMUTABLE)) { if (irqchip->irq_request_resources == gpiochip_irq_reqres) { irqchip->irq_request_resources = NULL; irqchip->irq_release_resources = NULL; } if (irqchip->irq_enable == gpiochip_irq_enable) { - irqchip->irq_enable = gpiochip->irq.irq_enable; - irqchip->irq_disable = gpiochip->irq.irq_disable; + irqchip->irq_enable = gc->irq.irq_enable; + irqchip->irq_disable = gc->irq.irq_disable; } } - gpiochip->irq.irq_enable = NULL; - gpiochip->irq.irq_disable = NULL; - gpiochip->irq.chip = NULL; + gc->irq.irq_enable = NULL; + gc->irq.irq_disable = NULL; + gc->irq.chip = NULL; - gpiochip_irqchip_free_valid_mask(gpiochip); + gpiochip_irqchip_free_valid_mask(gc); } /** - * gpiochip_irqchip_add_key() - adds an irqchip to a gpiochip - * @gpiochip: the gpiochip to add the irqchip to - * @irqchip: the irqchip to add to the gpiochip - * @first_irq: if not dynamically assigned, the base (first) IRQ to - * allocate gpiochip irqs from - * @handler: the irq handler to use (often a predefined irq core function) - * @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE - * to have the core avoid setting up any default type in the hardware. - * @threaded: whether this irqchip uses a nested thread handler - * @lock_key: lockdep class for IRQ lock - * @request_key: lockdep class for IRQ request + * gpiochip_irqchip_add_domain() - adds an irqdomain to a gpiochip + * @gc: the gpiochip to add the irqchip to + * @domain: the irqdomain to add to the gpiochip + * + * This function adds an IRQ domain to the gpiochip. * - * This function closely associates a certain irqchip with a certain - * gpiochip, providing an irq domain to translate the local IRQs to - * global irqs in the gpiolib core, and making sure that the gpiochip - * is passed as chip data to all related functions. Driver callbacks - * need to use gpiochip_get_data() to get their local state containers back - * from the gpiochip passed as chip data. An irqdomain will be stored - * in the gpiochip that shall be used by the driver to handle IRQ number - * translation. The gpiochip will need to be initialized and registered - * before calling this function. - * - * This function will handle two cell:ed simple IRQs and assumes all - * the pins on the gpiochip can generate a unique IRQ. Everything else - * need to be open coded. + * Returns: + * 0 on success, or negative errno on failure. */ -int gpiochip_irqchip_add_key(struct gpio_chip *gpiochip, - struct irq_chip *irqchip, - unsigned int first_irq, - irq_flow_handler_t handler, - unsigned int type, - bool threaded, - struct lock_class_key *lock_key, - struct lock_class_key *request_key) -{ - struct device_node *of_node; - - if (!gpiochip || !irqchip) - return -EINVAL; - - if (!gpiochip->parent) { - pr_err("missing gpiochip .dev parent pointer\n"); - return -EINVAL; - } - gpiochip->irq.threaded = threaded; - of_node = gpiochip->parent->of_node; -#ifdef CONFIG_OF_GPIO - /* - * If the gpiochip has an assigned OF node this takes precedence - * FIXME: get rid of this and use gpiochip->parent->of_node - * everywhere - */ - if (gpiochip->of_node) - of_node = gpiochip->of_node; -#endif - /* - * Specifying a default trigger is a terrible idea if DT or ACPI is - * used to configure the interrupts, as you may end-up with - * conflicting triggers. Tell the user, and reset to NONE. - */ - if (WARN(of_node && type != IRQ_TYPE_NONE, - "%pOF: Ignoring %d default trigger\n", of_node, type)) - type = IRQ_TYPE_NONE; - if (has_acpi_companion(gpiochip->parent) && type != IRQ_TYPE_NONE) { - acpi_handle_warn(ACPI_HANDLE(gpiochip->parent), - "Ignoring %d default trigger\n", type); - type = IRQ_TYPE_NONE; - } - - gpiochip->irq.chip = irqchip; - gpiochip->irq.handler = handler; - gpiochip->irq.default_type = type; - gpiochip->to_irq = gpiochip_to_irq; - gpiochip->irq.lock_key = lock_key; - gpiochip->irq.request_key = request_key; - gpiochip->irq.domain = irq_domain_add_simple(of_node, - gpiochip->ngpio, first_irq, - &gpiochip_domain_ops, gpiochip); - if (!gpiochip->irq.domain) { - gpiochip->irq.chip = NULL; - return -EINVAL; - } - - gpiochip_set_irq_hooks(gpiochip); - - acpi_gpiochip_request_interrupts(gpiochip); - - return 0; +int gpiochip_irqchip_add_domain(struct gpio_chip *gc, + struct irq_domain *domain) +{ + return gpiochip_irqchip_add_allocated_domain(gc, domain, true); } -EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_key); +EXPORT_SYMBOL_GPL(gpiochip_irqchip_add_domain); #else /* CONFIG_GPIOLIB_IRQCHIP */ -static inline int gpiochip_add_irqchip(struct gpio_chip *gpiochip, +static inline int gpiochip_add_irqchip(struct gpio_chip *gc, struct lock_class_key *lock_key, struct lock_class_key *request_key) { return 0; } +static void gpiochip_irqchip_remove(struct gpio_chip *gc) {} -static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) {} -static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip) +static inline int gpiochip_irqchip_init_hw(struct gpio_chip *gc) { return 0; } -static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gpiochip) + +static inline int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc) +{ + return 0; +} +static inline void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc) { } #endif /* CONFIG_GPIOLIB_IRQCHIP */ /** * gpiochip_generic_request() - request the gpio function for a pin - * @chip: the gpiochip owning the GPIO + * @gc: the gpiochip owning the GPIO * @offset: the offset of the GPIO to request for GPIO function + * + * Returns: + * 0 on success, or negative errno on failure. */ -int gpiochip_generic_request(struct gpio_chip *chip, unsigned offset) +int gpiochip_generic_request(struct gpio_chip *gc, unsigned int offset) { - return pinctrl_gpio_request(chip->gpiodev->base + offset); +#ifdef CONFIG_PINCTRL + if (list_empty(&gc->gpiodev->pin_ranges)) + return 0; +#endif + + return pinctrl_gpio_request(gc, offset); } EXPORT_SYMBOL_GPL(gpiochip_generic_request); /** * gpiochip_generic_free() - free the gpio function from a pin - * @chip: the gpiochip to request the gpio function for + * @gc: the gpiochip to request the gpio function for * @offset: the offset of the GPIO to free from GPIO function */ -void gpiochip_generic_free(struct gpio_chip *chip, unsigned offset) +void gpiochip_generic_free(struct gpio_chip *gc, unsigned int offset) { - pinctrl_gpio_free(chip->gpiodev->base + offset); +#ifdef CONFIG_PINCTRL + if (list_empty(&gc->gpiodev->pin_ranges)) + return; +#endif + + pinctrl_gpio_free(gc, offset); } EXPORT_SYMBOL_GPL(gpiochip_generic_free); /** * gpiochip_generic_config() - apply configuration for a pin - * @chip: the gpiochip owning the GPIO + * @gc: the gpiochip owning the GPIO * @offset: the offset of the GPIO to apply the configuration * @config: the configuration to be applied + * + * Returns: + * 0 on success, or negative errno on failure. */ -int gpiochip_generic_config(struct gpio_chip *chip, unsigned offset, +int gpiochip_generic_config(struct gpio_chip *gc, unsigned int offset, unsigned long config) { - return pinctrl_gpio_set_config(chip->gpiodev->base + offset, config); +#ifdef CONFIG_PINCTRL + if (list_empty(&gc->gpiodev->pin_ranges)) + return -ENOTSUPP; +#endif + + return pinctrl_gpio_set_config(gc, offset, config); } EXPORT_SYMBOL_GPL(gpiochip_generic_config); @@ -2130,7 +2315,7 @@ EXPORT_SYMBOL_GPL(gpiochip_generic_config); /** * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping - * @chip: the gpiochip to add the range for + * @gc: the gpiochip to add the range for * @pctldev: the pin controller to map to * @gpio_offset: the start offset in the current gpio_chip number space * @pin_group: name of the pin group inside the pin controller @@ -2139,25 +2324,26 @@ EXPORT_SYMBOL_GPL(gpiochip_generic_config); * pinctrl driver is DEPRECATED. Please see Section 2.1 of * Documentation/devicetree/bindings/gpio/gpio.txt on how to * bind pinctrl and gpio drivers via the "gpio-ranges" property. + * + * Returns: + * 0 on success, or negative errno on failure. */ -int gpiochip_add_pingroup_range(struct gpio_chip *chip, +int gpiochip_add_pingroup_range(struct gpio_chip *gc, struct pinctrl_dev *pctldev, unsigned int gpio_offset, const char *pin_group) { struct gpio_pin_range *pin_range; - struct gpio_device *gdev = chip->gpiodev; + struct gpio_device *gdev = gc->gpiodev; int ret; pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); - if (!pin_range) { - chip_err(chip, "failed to allocate pin ranges\n"); + if (!pin_range) return -ENOMEM; - } /* Use local offset as range ID */ pin_range->range.id = gpio_offset; - pin_range->range.gc = chip; - pin_range->range.name = chip->label; + pin_range->range.gc = gc; + pin_range->range.name = gc->label; pin_range->range.base = gdev->base + gpio_offset; pin_range->pctldev = pctldev; @@ -2171,7 +2357,7 @@ int gpiochip_add_pingroup_range(struct gpio_chip *chip, pinctrl_add_gpio_range(pctldev, &pin_range->range); - chip_dbg(chip, "created GPIO range %d->%d ==> %s PINGRP %s\n", + gpiochip_dbg(gc, "created GPIO range %d->%d ==> %s PINGRP %s\n", gpio_offset, gpio_offset + pin_range->range.npins - 1, pinctrl_dev_get_devname(pctldev), pin_group); @@ -2182,70 +2368,78 @@ int gpiochip_add_pingroup_range(struct gpio_chip *chip, EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range); /** - * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping - * @chip: the gpiochip to add the range for + * gpiochip_add_pin_range_with_pins() - add a range for GPIO <-> pin mapping + * @gc: the gpiochip to add the range for * @pinctl_name: the dev_name() of the pin controller to map to * @gpio_offset: the start offset in the current gpio_chip number space * @pin_offset: the start offset in the pin controller number space + * @pins: the list of non consecutive pins to accumulate in this range (if not + * NULL, pin_offset is ignored by pinctrl core) * @npins: the number of pins from the offset of each pin space (GPIO and * pin controller) to accumulate in this range * - * Returns: - * 0 on success, or a negative error-code on failure. - * * Calling this function directly from a DeviceTree-supported * pinctrl driver is DEPRECATED. Please see Section 2.1 of * Documentation/devicetree/bindings/gpio/gpio.txt on how to * bind pinctrl and gpio drivers via the "gpio-ranges" property. + * + * Returns: + * 0 on success, or a negative errno on failure. */ -int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name, - unsigned int gpio_offset, unsigned int pin_offset, - unsigned int npins) +int gpiochip_add_pin_range_with_pins(struct gpio_chip *gc, + const char *pinctl_name, + unsigned int gpio_offset, + unsigned int pin_offset, + unsigned int const *pins, + unsigned int npins) { struct gpio_pin_range *pin_range; - struct gpio_device *gdev = chip->gpiodev; + struct gpio_device *gdev = gc->gpiodev; int ret; pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); - if (!pin_range) { - chip_err(chip, "failed to allocate pin ranges\n"); + if (!pin_range) return -ENOMEM; - } /* Use local offset as range ID */ pin_range->range.id = gpio_offset; - pin_range->range.gc = chip; - pin_range->range.name = chip->label; + pin_range->range.gc = gc; + pin_range->range.name = gc->label; pin_range->range.base = gdev->base + gpio_offset; pin_range->range.pin_base = pin_offset; + pin_range->range.pins = pins; pin_range->range.npins = npins; pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name, &pin_range->range); if (IS_ERR(pin_range->pctldev)) { ret = PTR_ERR(pin_range->pctldev); - chip_err(chip, "could not create pin range\n"); + gpiochip_err(gc, "could not create pin range\n"); kfree(pin_range); return ret; } - chip_dbg(chip, "created GPIO range %d->%d ==> %s PIN %d->%d\n", - gpio_offset, gpio_offset + npins - 1, - pinctl_name, - pin_offset, pin_offset + npins - 1); + if (pin_range->range.pins) + gpiochip_dbg(gc, "created GPIO range %d->%d ==> %s %d sparse PIN range { %d, ... }", + gpio_offset, gpio_offset + npins - 1, + pinctl_name, npins, pins[0]); + else + gpiochip_dbg(gc, "created GPIO range %d->%d ==> %s PIN %d->%d\n", + gpio_offset, gpio_offset + npins - 1, pinctl_name, + pin_offset, pin_offset + npins - 1); list_add_tail(&pin_range->node, &gdev->pin_ranges); return 0; } -EXPORT_SYMBOL_GPL(gpiochip_add_pin_range); +EXPORT_SYMBOL_GPL(gpiochip_add_pin_range_with_pins); /** * gpiochip_remove_pin_ranges() - remove all the GPIO <-> pin mappings - * @chip: the chip to remove all the mappings for + * @gc: the chip to remove all the mappings for */ -void gpiochip_remove_pin_ranges(struct gpio_chip *chip) +void gpiochip_remove_pin_ranges(struct gpio_chip *gc) { struct gpio_pin_range *pin_range, *tmp; - struct gpio_device *gdev = chip->gpiodev; + struct gpio_device *gdev = gc->gpiodev; list_for_each_entry_safe(pin_range, tmp, &gdev->pin_ranges, node) { list_del(&pin_range->node); @@ -2264,198 +2458,160 @@ EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges); */ static int gpiod_request_commit(struct gpio_desc *desc, const char *label) { - struct gpio_chip *chip = desc->gdev->chip; - int status; - unsigned long flags; - unsigned offset; + unsigned int offset; + int ret; - if (label) { - label = kstrdup_const(label, GFP_KERNEL); - if (!label) - return -ENOMEM; - } + CLASS(gpio_chip_guard, guard)(desc); + if (!guard.gc) + return -ENODEV; + + if (test_and_set_bit(GPIOD_FLAG_REQUESTED, &desc->flags)) + return -EBUSY; - spin_lock_irqsave(&gpio_lock, flags); + offset = gpiod_hwgpio(desc); + if (!gpiochip_line_is_valid(guard.gc, offset)) + return -EINVAL; /* NOTE: gpio_request() can be called in early boot, * before IRQs are enabled, for non-sleeping (SOC) GPIOs. */ - if (test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0) { - desc_set_label(desc, label ? : "?"); - status = 0; - } else { - kfree_const(label); - status = -EBUSY; - goto done; + if (guard.gc->request) { + ret = guard.gc->request(guard.gc, offset); + if (ret > 0) + ret = -EBADE; + if (ret) + goto out_clear_bit; } - if (chip->request) { - /* chip->request may sleep */ - spin_unlock_irqrestore(&gpio_lock, flags); - offset = gpio_chip_hwgpio(desc); - if (gpiochip_line_is_valid(chip, offset)) - status = chip->request(chip, offset); - else - status = -EINVAL; - spin_lock_irqsave(&gpio_lock, flags); - - if (status < 0) { - desc_set_label(desc, NULL); - kfree_const(label); - clear_bit(FLAG_REQUESTED, &desc->flags); - goto done; - } - } - if (chip->get_direction) { - /* chip->get_direction may sleep */ - spin_unlock_irqrestore(&gpio_lock, flags); + if (guard.gc->get_direction) gpiod_get_direction(desc); - spin_lock_irqsave(&gpio_lock, flags); - } -done: - spin_unlock_irqrestore(&gpio_lock, flags); - return status; -} -/* - * This descriptor validation needs to be inserted verbatim into each - * function taking a descriptor, so we need to use a preprocessor - * macro to avoid endless duplication. If the desc is NULL it is an - * optional GPIO and calls should just bail out. - */ -static int validate_desc(const struct gpio_desc *desc, const char *func) -{ - if (!desc) - return 0; - if (IS_ERR(desc)) { - pr_warn("%s: invalid GPIO (errorpointer)\n", func); - return PTR_ERR(desc); - } - if (!desc->gdev) { - pr_warn("%s: invalid GPIO (no device)\n", func); - return -EINVAL; - } - if (!desc->gdev->chip) { - dev_warn(&desc->gdev->dev, - "%s: backing chip is gone\n", func); - return 0; - } - return 1; -} + ret = desc_set_label(desc, label ? : "?"); + if (ret) + goto out_clear_bit; -#define VALIDATE_DESC(desc) do { \ - int __valid = validate_desc(desc, __func__); \ - if (__valid <= 0) \ - return __valid; \ - } while (0) + return 0; -#define VALIDATE_DESC_VOID(desc) do { \ - int __valid = validate_desc(desc, __func__); \ - if (__valid <= 0) \ - return; \ - } while (0) +out_clear_bit: + clear_bit(GPIOD_FLAG_REQUESTED, &desc->flags); + return ret; +} int gpiod_request(struct gpio_desc *desc, const char *label) { - int status = -EPROBE_DEFER; - struct gpio_device *gdev; + int ret = -EPROBE_DEFER; VALIDATE_DESC(desc); - gdev = desc->gdev; - if (try_module_get(gdev->owner)) { - status = gpiod_request_commit(desc, label); - if (status < 0) - module_put(gdev->owner); + if (try_module_get(desc->gdev->owner)) { + ret = gpiod_request_commit(desc, label); + if (ret) + module_put(desc->gdev->owner); else - get_device(&gdev->dev); + gpio_device_get(desc->gdev); } - if (status) - gpiod_dbg(desc, "%s: status %d\n", __func__, status); + if (ret) + gpiod_dbg(desc, "%s: status %d\n", __func__, ret); - return status; + return ret; } -static bool gpiod_free_commit(struct gpio_desc *desc) +static void gpiod_free_commit(struct gpio_desc *desc) { - bool ret = false; - unsigned long flags; - struct gpio_chip *chip; + unsigned long flags; might_sleep(); - gpiod_unexport(desc); - - spin_lock_irqsave(&gpio_lock, flags); - - chip = desc->gdev->chip; - if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) { - if (chip->free) { - spin_unlock_irqrestore(&gpio_lock, flags); - might_sleep_if(chip->can_sleep); - chip->free(chip, gpio_chip_hwgpio(desc)); - spin_lock_irqsave(&gpio_lock, flags); - } - kfree_const(desc->label); + CLASS(gpio_chip_guard, guard)(desc); + + flags = READ_ONCE(desc->flags); + + if (guard.gc && test_bit(GPIOD_FLAG_REQUESTED, &flags)) { + if (guard.gc->free) + guard.gc->free(guard.gc, gpiod_hwgpio(desc)); + + clear_bit(GPIOD_FLAG_ACTIVE_LOW, &flags); + clear_bit(GPIOD_FLAG_REQUESTED, &flags); + clear_bit(GPIOD_FLAG_OPEN_DRAIN, &flags); + clear_bit(GPIOD_FLAG_OPEN_SOURCE, &flags); + clear_bit(GPIOD_FLAG_PULL_UP, &flags); + clear_bit(GPIOD_FLAG_PULL_DOWN, &flags); + clear_bit(GPIOD_FLAG_BIAS_DISABLE, &flags); + clear_bit(GPIOD_FLAG_EDGE_RISING, &flags); + clear_bit(GPIOD_FLAG_EDGE_FALLING, &flags); + clear_bit(GPIOD_FLAG_IS_HOGGED, &flags); +#ifdef CONFIG_OF_DYNAMIC + WRITE_ONCE(desc->hog, NULL); +#endif desc_set_label(desc, NULL); - clear_bit(FLAG_ACTIVE_LOW, &desc->flags); - clear_bit(FLAG_REQUESTED, &desc->flags); - clear_bit(FLAG_OPEN_DRAIN, &desc->flags); - clear_bit(FLAG_OPEN_SOURCE, &desc->flags); - clear_bit(FLAG_IS_HOGGED, &desc->flags); - ret = true; + WRITE_ONCE(desc->flags, flags); +#ifdef CONFIG_GPIO_CDEV + WRITE_ONCE(desc->debounce_period_us, 0); +#endif + gpiod_line_state_notify(desc, GPIO_V2_LINE_CHANGED_RELEASED); } - - spin_unlock_irqrestore(&gpio_lock, flags); - return ret; } void gpiod_free(struct gpio_desc *desc) { - if (desc && desc->gdev && gpiod_free_commit(desc)) { - module_put(desc->gdev->owner); - put_device(&desc->gdev->dev); - } else { - WARN_ON(extra_checks); - } + VALIDATE_DESC_VOID(desc); + + gpiod_free_commit(desc); + module_put(desc->gdev->owner); + gpio_device_put(desc->gdev); } /** - * gpiochip_is_requested - return string iff signal was requested - * @chip: controller managing the signal - * @offset: of signal within controller's 0..(ngpio - 1) range + * gpiochip_dup_line_label - Get a copy of the consumer label. + * @gc: GPIO chip controlling this line. + * @offset: Hardware offset of the line. * - * Returns NULL if the GPIO is not currently requested, else a string. - * The string returned is the label passed to gpio_request(); if none has been - * passed it is a meaningless, non-NULL constant. + * Returns: + * Pointer to a copy of the consumer label if the line is requested or NULL + * if it's not. If a valid pointer was returned, it must be freed using + * kfree(). In case of a memory allocation error, the function returns %ENOMEM. * - * This function is for use by GPIO controller drivers. The label can - * help with diagnostics, and knowing that the signal is used as a GPIO - * can help avoid accidentally multiplexing it to another controller. + * Must not be called from atomic context. */ -const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset) +char *gpiochip_dup_line_label(struct gpio_chip *gc, unsigned int offset) { struct gpio_desc *desc; + char *label; + + desc = gpiochip_get_desc(gc, offset); + if (IS_ERR(desc)) + return NULL; - if (offset >= chip->ngpio) + if (!test_bit(GPIOD_FLAG_REQUESTED, &desc->flags)) return NULL; - desc = &chip->gpiodev->descs[offset]; + guard(srcu)(&desc->gdev->desc_srcu); - if (test_bit(FLAG_REQUESTED, &desc->flags) == 0) - return NULL; - return desc->label; + label = kstrdup(gpiod_get_label(desc), GFP_KERNEL); + if (!label) + return ERR_PTR(-ENOMEM); + + return label; +} +EXPORT_SYMBOL_GPL(gpiochip_dup_line_label); + +static inline const char *function_name_or_default(const char *con_id) +{ + return con_id ?: "(default)"; } -EXPORT_SYMBOL_GPL(gpiochip_is_requested); /** * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor - * @chip: GPIO chip + * @gc: GPIO chip * @hwnum: hardware number of the GPIO for which to request the descriptor * @label: label for the GPIO - * @flags: flags for this GPIO or 0 if default + * @lflags: lookup flags for this GPIO or 0 if default, this can be used to + * specify things like line inversion semantics with the machine flags + * such as GPIO_OUT_LOW + * @dflags: descriptor request flags for this GPIO or 0 if default, this + * can be used to specify consumer semantics such as open drain * * Function allows GPIO chip drivers to request and use their own GPIO * descriptors via gpiolib API. Difference to gpiod_request() is that this @@ -2467,29 +2623,34 @@ EXPORT_SYMBOL_GPL(gpiochip_is_requested); * A pointer to the GPIO descriptor, or an ERR_PTR()-encoded negative error * code on failure. */ -struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip, u16 hwnum, +struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc, + unsigned int hwnum, const char *label, - enum gpiod_flags flags) + enum gpio_lookup_flags lflags, + enum gpiod_flags dflags) { - struct gpio_desc *desc = gpiochip_get_desc(chip, hwnum); - int err; + struct gpio_desc *desc = gpiochip_get_desc(gc, hwnum); + const char *name = function_name_or_default(label); + int ret; if (IS_ERR(desc)) { - chip_err(chip, "failed to get GPIO descriptor\n"); + gpiochip_err(gc, "failed to get GPIO %s descriptor\n", name); return desc; } - err = gpiod_request_commit(desc, label); - if (err < 0) - return ERR_PTR(err); + ret = gpiod_request_commit(desc, label); + if (ret < 0) + return ERR_PTR(ret); - err = gpiod_configure_flags(desc, label, 0, flags); - if (err) { - chip_err(chip, "setup of own GPIO %s failed\n", label); + ret = gpiod_configure_flags(desc, label, lflags, dflags); + if (ret) { gpiod_free_commit(desc); - return ERR_PTR(err); + gpiochip_err(gc, "setup of own GPIO %s failed\n", name); + return ERR_PTR(ret); } + gpiod_line_state_notify(desc, GPIO_V2_LINE_CHANGED_REQUESTED); + return desc; } EXPORT_SYMBOL_GPL(gpiochip_request_own_desc); @@ -2518,6 +2679,159 @@ EXPORT_SYMBOL_GPL(gpiochip_free_own_desc); * rely on gpio_request() having been called beforehand. */ +int gpio_do_set_config(struct gpio_desc *desc, unsigned long config) +{ + int ret; + + CLASS(gpio_chip_guard, guard)(desc); + if (!guard.gc) + return -ENODEV; + + if (!guard.gc->set_config) + return -ENOTSUPP; + + ret = guard.gc->set_config(guard.gc, gpiod_hwgpio(desc), config); + if (ret > 0) + ret = -EBADE; + +#ifdef CONFIG_GPIO_CDEV + /* + * Special case - if we're setting debounce period, we need to store + * it in the descriptor in case user-space wants to know it. + */ + if (!ret && pinconf_to_config_param(config) == PIN_CONFIG_INPUT_DEBOUNCE) + WRITE_ONCE(desc->debounce_period_us, + pinconf_to_config_argument(config)); +#endif + return ret; +} + +static int gpio_set_config_with_argument(struct gpio_desc *desc, + enum pin_config_param mode, + u32 argument) +{ + unsigned long config; + + config = pinconf_to_config_packed(mode, argument); + return gpio_do_set_config(desc, config); +} + +static int gpio_set_config_with_argument_optional(struct gpio_desc *desc, + enum pin_config_param mode, + u32 argument) +{ + struct device *dev = &desc->gdev->dev; + int gpio = gpiod_hwgpio(desc); + int ret; + + ret = gpio_set_config_with_argument(desc, mode, argument); + if (ret != -ENOTSUPP) + return ret; + + switch (mode) { + case PIN_CONFIG_PERSIST_STATE: + dev_dbg(dev, "Persistence not supported for GPIO %d\n", gpio); + break; + default: + break; + } + + return 0; +} + +static int gpio_set_config(struct gpio_desc *desc, enum pin_config_param mode) +{ + return gpio_set_config_with_argument(desc, mode, 0); +} + +static int gpio_set_bias(struct gpio_desc *desc) +{ + enum pin_config_param bias; + unsigned long flags; + unsigned int arg; + + flags = READ_ONCE(desc->flags); + + if (test_bit(GPIOD_FLAG_BIAS_DISABLE, &flags)) + bias = PIN_CONFIG_BIAS_DISABLE; + else if (test_bit(GPIOD_FLAG_PULL_UP, &flags)) + bias = PIN_CONFIG_BIAS_PULL_UP; + else if (test_bit(GPIOD_FLAG_PULL_DOWN, &flags)) + bias = PIN_CONFIG_BIAS_PULL_DOWN; + else + return 0; + + switch (bias) { + case PIN_CONFIG_BIAS_PULL_DOWN: + case PIN_CONFIG_BIAS_PULL_UP: + arg = 1; + break; + + default: + arg = 0; + break; + } + + return gpio_set_config_with_argument_optional(desc, bias, arg); +} + +/** + * gpio_set_debounce_timeout() - Set debounce timeout + * @desc: GPIO descriptor to set the debounce timeout + * @debounce: Debounce timeout in microseconds + * + * The function calls the certain GPIO driver to set debounce timeout + * in the hardware. + * + * Returns: + * 0 on success, or negative errno on failure. + */ +int gpio_set_debounce_timeout(struct gpio_desc *desc, unsigned int debounce) +{ + int ret; + + ret = gpio_set_config_with_argument_optional(desc, + PIN_CONFIG_INPUT_DEBOUNCE, + debounce); + if (!ret) + gpiod_line_state_notify(desc, GPIO_V2_LINE_CHANGED_CONFIG); + + return ret; +} + +static int gpiochip_direction_input(struct gpio_chip *gc, unsigned int offset) +{ + int ret; + + lockdep_assert_held(&gc->gpiodev->srcu); + + if (WARN_ON(!gc->direction_input)) + return -EOPNOTSUPP; + + ret = gc->direction_input(gc, offset); + if (ret > 0) + ret = -EBADE; + + return ret; +} + +static int gpiochip_direction_output(struct gpio_chip *gc, unsigned int offset, + int value) +{ + int ret; + + lockdep_assert_held(&gc->gpiodev->srcu); + + if (WARN_ON(!gc->direction_output)) + return -EOPNOTSUPP; + + ret = gc->direction_output(gc, offset, value); + if (ret > 0) + ret = -EBADE; + + return ret; +} + /** * gpiod_direction_input - set the GPIO direction to input * @desc: GPIO to set to input @@ -2525,22 +2839,37 @@ EXPORT_SYMBOL_GPL(gpiochip_free_own_desc); * Set the direction of the passed GPIO to input, such as gpiod_get_value() can * be called safely on it. * - * Return 0 in case of success, else an error code. + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_direction_input(struct gpio_desc *desc) { - struct gpio_chip *chip; - int status = 0; + int ret; VALIDATE_DESC(desc); - chip = desc->gdev->chip; + + ret = gpiod_direction_input_nonotify(desc); + if (ret == 0) + gpiod_line_state_notify(desc, GPIO_V2_LINE_CHANGED_CONFIG); + + return ret; +} +EXPORT_SYMBOL_GPL(gpiod_direction_input); + +int gpiod_direction_input_nonotify(struct gpio_desc *desc) +{ + int ret = 0, dir; + + CLASS(gpio_chip_guard, guard)(desc); + if (!guard.gc) + return -ENODEV; /* * It is legal to have no .get() and .direction_input() specified if * the chip is output-only, but you can't specify .direction_input() * and not support the .get() operation, that doesn't make sense. */ - if (!chip->get && chip->direction_input) { + if (!guard.gc->get && guard.gc->direction_input) { gpiod_warn(desc, "%s: missing get() but have direction_input()\n", __func__); @@ -2553,70 +2882,96 @@ int gpiod_direction_input(struct gpio_desc *desc) * direction (if .get_direction() is supported) else we silently * assume we are in input mode after this. */ - if (chip->direction_input) { - status = chip->direction_input(chip, gpio_chip_hwgpio(desc)); - } else if (chip->get_direction && - (chip->get_direction(chip, gpio_chip_hwgpio(desc)) != 1)) { - gpiod_warn(desc, - "%s: missing direction_input() operation and line is output\n", - __func__); - return -EIO; + if (guard.gc->direction_input) { + ret = gpiochip_direction_input(guard.gc, + gpiod_hwgpio(desc)); + } else if (guard.gc->get_direction) { + dir = gpiochip_get_direction(guard.gc, gpiod_hwgpio(desc)); + if (dir < 0) + return dir; + + if (dir != GPIO_LINE_DIRECTION_IN) { + gpiod_warn(desc, + "%s: missing direction_input() operation and line is output\n", + __func__); + return -EIO; + } + } + if (ret == 0) { + clear_bit(GPIOD_FLAG_IS_OUT, &desc->flags); + ret = gpio_set_bias(desc); } - if (status == 0) - clear_bit(FLAG_IS_OUT, &desc->flags); - trace_gpio_direction(desc_to_gpio(desc), 1, status); + trace_gpio_direction(desc_to_gpio(desc), 1, ret); - return status; + return ret; } -EXPORT_SYMBOL_GPL(gpiod_direction_input); -static int gpio_set_drive_single_ended(struct gpio_chip *gc, unsigned offset, - enum pin_config_param mode) +static int gpiochip_set(struct gpio_chip *gc, unsigned int offset, int value) { - unsigned long config = { PIN_CONF_PACKED(mode, 0) }; + int ret; + + lockdep_assert_held(&gc->gpiodev->srcu); + + if (WARN_ON(unlikely(!gc->set))) + return -EOPNOTSUPP; - return gc->set_config ? gc->set_config(gc, offset, config) : -ENOTSUPP; + ret = gc->set(gc, offset, value); + if (ret > 0) + ret = -EBADE; + + return ret; } static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value) { - struct gpio_chip *gc = desc->gdev->chip; - int val = !!value; - int ret = 0; + int val = !!value, ret = 0, dir; + + CLASS(gpio_chip_guard, guard)(desc); + if (!guard.gc) + return -ENODEV; /* * It's OK not to specify .direction_output() if the gpiochip is * output-only, but if there is then not even a .set() operation it * is pretty tricky to drive the output line. */ - if (!gc->set && !gc->direction_output) { + if (!guard.gc->set && !guard.gc->direction_output) { gpiod_warn(desc, "%s: missing set() and direction_output() operations\n", __func__); return -EIO; } - if (gc->direction_output) { - ret = gc->direction_output(gc, gpio_chip_hwgpio(desc), val); + if (guard.gc->direction_output) { + ret = gpiochip_direction_output(guard.gc, + gpiod_hwgpio(desc), val); } else { /* Check that we are in output mode if we can */ - if (gc->get_direction && - gc->get_direction(gc, gpio_chip_hwgpio(desc))) { - gpiod_warn(desc, - "%s: missing direction_output() operation\n", - __func__); - return -EIO; + if (guard.gc->get_direction) { + dir = gpiochip_get_direction(guard.gc, + gpiod_hwgpio(desc)); + if (dir < 0) + return dir; + + if (dir != GPIO_LINE_DIRECTION_OUT) { + gpiod_warn(desc, + "%s: missing direction_output() operation\n", + __func__); + return -EIO; + } } /* * If we can't actively set the direction, we are some * output-only chip, so just drive the output as desired. */ - gc->set(gc, gpio_chip_hwgpio(desc), val); + ret = gpiochip_set(guard.gc, gpiod_hwgpio(desc), val); + if (ret) + return ret; } if (!ret) - set_bit(FLAG_IS_OUT, &desc->flags); + set_bit(GPIOD_FLAG_IS_OUT, &desc->flags); trace_gpio_value(desc_to_gpio(desc), 0, val); trace_gpio_direction(desc_to_gpio(desc), 0, ret); return ret; @@ -2631,12 +2986,20 @@ static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value) * be called safely on it. The initial value of the output must be specified * as raw value on the physical line without regard for the ACTIVE_LOW status. * - * Return 0 in case of success, else an error code. + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_direction_output_raw(struct gpio_desc *desc, int value) { + int ret; + VALIDATE_DESC(desc); - return gpiod_direction_output_raw_commit(desc, value); + + ret = gpiod_direction_output_raw_commit(desc, value); + if (ret == 0) + gpiod_line_state_notify(desc, GPIO_V2_LINE_CHANGED_CONFIG); + + return ret; } EXPORT_SYMBOL_GPL(gpiod_direction_output_raw); @@ -2650,56 +3013,188 @@ EXPORT_SYMBOL_GPL(gpiod_direction_output_raw); * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into * account. * - * Return 0 in case of success, else an error code. + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_direction_output(struct gpio_desc *desc, int value) { - struct gpio_chip *gc; int ret; VALIDATE_DESC(desc); - if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) + + ret = gpiod_direction_output_nonotify(desc, value); + if (ret == 0) + gpiod_line_state_notify(desc, GPIO_V2_LINE_CHANGED_CONFIG); + + return ret; +} +EXPORT_SYMBOL_GPL(gpiod_direction_output); + +int gpiod_direction_output_nonotify(struct gpio_desc *desc, int value) +{ + unsigned long flags; + int ret; + + flags = READ_ONCE(desc->flags); + + if (test_bit(GPIOD_FLAG_ACTIVE_LOW, &flags)) value = !value; else value = !!value; /* GPIOs used for enabled IRQs shall not be set as output */ - if (test_bit(FLAG_USED_AS_IRQ, &desc->flags) && - test_bit(FLAG_IRQ_IS_ENABLED, &desc->flags)) { + if (test_bit(GPIOD_FLAG_USED_AS_IRQ, &flags) && + test_bit(GPIOD_FLAG_IRQ_IS_ENABLED, &flags)) { gpiod_err(desc, "%s: tried to set a GPIO tied to an IRQ as output\n", __func__); return -EIO; } - gc = desc->gdev->chip; - if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) { + if (test_bit(GPIOD_FLAG_OPEN_DRAIN, &flags)) { /* First see if we can enable open drain in hardware */ - ret = gpio_set_drive_single_ended(gc, gpio_chip_hwgpio(desc), - PIN_CONFIG_DRIVE_OPEN_DRAIN); + ret = gpio_set_config(desc, PIN_CONFIG_DRIVE_OPEN_DRAIN); if (!ret) goto set_output_value; /* Emulate open drain by not actively driving the line high */ if (value) - return gpiod_direction_input(desc); - } - else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) { - ret = gpio_set_drive_single_ended(gc, gpio_chip_hwgpio(desc), - PIN_CONFIG_DRIVE_OPEN_SOURCE); + goto set_output_flag; + } else if (test_bit(GPIOD_FLAG_OPEN_SOURCE, &flags)) { + ret = gpio_set_config(desc, PIN_CONFIG_DRIVE_OPEN_SOURCE); if (!ret) goto set_output_value; /* Emulate open source by not actively driving the line low */ if (!value) - return gpiod_direction_input(desc); + goto set_output_flag; } else { - gpio_set_drive_single_ended(gc, gpio_chip_hwgpio(desc), - PIN_CONFIG_DRIVE_PUSH_PULL); + gpio_set_config(desc, PIN_CONFIG_DRIVE_PUSH_PULL); } set_output_value: + ret = gpio_set_bias(desc); + if (ret) + return ret; return gpiod_direction_output_raw_commit(desc, value); + +set_output_flag: + ret = gpiod_direction_input_nonotify(desc); + if (ret) + return ret; + /* + * When emulating open-source or open-drain functionalities by not + * actively driving the line (setting mode to input) we still need to + * set the IS_OUT flag or otherwise we won't be able to set the line + * value anymore. + */ + set_bit(GPIOD_FLAG_IS_OUT, &desc->flags); + return 0; } -EXPORT_SYMBOL_GPL(gpiod_direction_output); + +#if IS_ENABLED(CONFIG_HTE) +/** + * gpiod_enable_hw_timestamp_ns - Enable hardware timestamp in nanoseconds. + * + * @desc: GPIO to enable. + * @flags: Flags related to GPIO edge. + * + * Returns: + * 0 on success, or negative errno on failure. + */ +int gpiod_enable_hw_timestamp_ns(struct gpio_desc *desc, unsigned long flags) +{ + int ret; + + VALIDATE_DESC(desc); + + CLASS(gpio_chip_guard, guard)(desc); + if (!guard.gc) + return -ENODEV; + + if (!guard.gc->en_hw_timestamp) { + gpiod_warn(desc, "%s: hw ts not supported\n", __func__); + return -ENOTSUPP; + } + + ret = guard.gc->en_hw_timestamp(guard.gc, + gpiod_hwgpio(desc), flags); + if (ret) + gpiod_warn(desc, "%s: hw ts request failed\n", __func__); + + return ret; +} +EXPORT_SYMBOL_GPL(gpiod_enable_hw_timestamp_ns); + +/** + * gpiod_disable_hw_timestamp_ns - Disable hardware timestamp. + * + * @desc: GPIO to disable. + * @flags: Flags related to GPIO edge, same value as used during enable call. + * + * Returns: + * 0 on success, or negative errno on failure. + */ +int gpiod_disable_hw_timestamp_ns(struct gpio_desc *desc, unsigned long flags) +{ + int ret; + + VALIDATE_DESC(desc); + + CLASS(gpio_chip_guard, guard)(desc); + if (!guard.gc) + return -ENODEV; + + if (!guard.gc->dis_hw_timestamp) { + gpiod_warn(desc, "%s: hw ts not supported\n", __func__); + return -ENOTSUPP; + } + + ret = guard.gc->dis_hw_timestamp(guard.gc, gpiod_hwgpio(desc), + flags); + if (ret) + gpiod_warn(desc, "%s: hw ts release failed\n", __func__); + + return ret; +} +EXPORT_SYMBOL_GPL(gpiod_disable_hw_timestamp_ns); +#endif /* CONFIG_HTE */ + +/** + * gpiod_set_config - sets @config for a GPIO + * @desc: descriptor of the GPIO for which to set the configuration + * @config: Same packed config format as generic pinconf + * + * Returns: + * 0 on success, %-ENOTSUPP if the controller doesn't support setting the + * configuration. + */ +int gpiod_set_config(struct gpio_desc *desc, unsigned long config) +{ + int ret; + + VALIDATE_DESC(desc); + + ret = gpio_do_set_config(desc, config); + if (!ret) { + /* These are the only options we notify the userspace about. */ + switch (pinconf_to_config_param(config)) { + case PIN_CONFIG_BIAS_DISABLE: + case PIN_CONFIG_BIAS_PULL_DOWN: + case PIN_CONFIG_BIAS_PULL_UP: + case PIN_CONFIG_DRIVE_OPEN_DRAIN: + case PIN_CONFIG_DRIVE_OPEN_SOURCE: + case PIN_CONFIG_DRIVE_PUSH_PULL: + case PIN_CONFIG_INPUT_DEBOUNCE: + gpiod_line_state_notify(desc, + GPIO_V2_LINE_CHANGED_CONFIG); + break; + default: + break; + } + } + + return ret; +} +EXPORT_SYMBOL_GPL(gpiod_set_config); /** * gpiod_set_debounce - sets @debounce time for a GPIO @@ -2710,22 +3205,12 @@ EXPORT_SYMBOL_GPL(gpiod_direction_output); * 0 on success, %-ENOTSUPP if the controller doesn't support setting the * debounce time. */ -int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce) +int gpiod_set_debounce(struct gpio_desc *desc, unsigned int debounce) { - struct gpio_chip *chip; - unsigned long config; - - VALIDATE_DESC(desc); - chip = desc->gdev->chip; - if (!chip->set || !chip->set_config) { - gpiod_dbg(desc, - "%s: missing set() or set_config() operations\n", - __func__); - return -ENOTSUPP; - } + unsigned long config; config = pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE, debounce); - return chip->set_config(chip, gpio_chip_hwgpio(desc), config); + return gpiod_set_config(desc, config); } EXPORT_SYMBOL_GPL(gpiod_set_debounce); @@ -2739,53 +3224,64 @@ EXPORT_SYMBOL_GPL(gpiod_set_debounce); */ int gpiod_set_transitory(struct gpio_desc *desc, bool transitory) { - struct gpio_chip *chip; - unsigned long packed; - int gpio; - int rc; - VALIDATE_DESC(desc); /* - * Handle FLAG_TRANSITORY first, enabling queries to gpiolib for + * Handle GPIOD_FLAG_TRANSITORY first, enabling queries to gpiolib for * persistence state. */ - if (transitory) - set_bit(FLAG_TRANSITORY, &desc->flags); - else - clear_bit(FLAG_TRANSITORY, &desc->flags); + assign_bit(GPIOD_FLAG_TRANSITORY, &desc->flags, transitory); /* If the driver supports it, set the persistence state now */ - chip = desc->gdev->chip; - if (!chip->set_config) - return 0; - - packed = pinconf_to_config_packed(PIN_CONFIG_PERSIST_STATE, - !transitory); - gpio = gpio_chip_hwgpio(desc); - rc = chip->set_config(chip, gpio, packed); - if (rc == -ENOTSUPP) { - dev_dbg(&desc->gdev->dev, "Persistence not supported for GPIO %d\n", - gpio); - return 0; - } - - return rc; + return gpio_set_config_with_argument_optional(desc, + PIN_CONFIG_PERSIST_STATE, + !transitory); } -EXPORT_SYMBOL_GPL(gpiod_set_transitory); /** * gpiod_is_active_low - test whether a GPIO is active-low or not * @desc: the gpio descriptor to test * - * Returns 1 if the GPIO is active-low, 0 otherwise. + * Returns: + * 1 if the GPIO is active-low, 0 otherwise. */ int gpiod_is_active_low(const struct gpio_desc *desc) { VALIDATE_DESC(desc); - return test_bit(FLAG_ACTIVE_LOW, &desc->flags); + return test_bit(GPIOD_FLAG_ACTIVE_LOW, &desc->flags); } EXPORT_SYMBOL_GPL(gpiod_is_active_low); +/** + * gpiod_toggle_active_low - toggle whether a GPIO is active-low or not + * @desc: the gpio descriptor to change + */ +void gpiod_toggle_active_low(struct gpio_desc *desc) +{ + VALIDATE_DESC_VOID(desc); + change_bit(GPIOD_FLAG_ACTIVE_LOW, &desc->flags); + gpiod_line_state_notify(desc, GPIO_V2_LINE_CHANGED_CONFIG); +} +EXPORT_SYMBOL_GPL(gpiod_toggle_active_low); + +static int gpiochip_get(struct gpio_chip *gc, unsigned int offset) +{ + int ret; + + lockdep_assert_held(&gc->gpiodev->srcu); + + /* Make sure this is called after checking for gc->get(). */ + ret = gc->get(gc, offset); + if (ret > 1) + ret = -EBADE; + + return ret; +} + +static int gpio_chip_get_value(struct gpio_chip *gc, const struct gpio_desc *desc) +{ + return gc->get ? gpiochip_get(gc, gpiod_hwgpio(desc)) : -EIO; +} + /* I/O calls are only valid after configuration completed; the relevant * "is this a valid GPIO" error checks should already have been done. * @@ -2810,28 +3306,44 @@ EXPORT_SYMBOL_GPL(gpiod_is_active_low); static int gpiod_get_raw_value_commit(const struct gpio_desc *desc) { - struct gpio_chip *chip; - int offset; + struct gpio_device *gdev; + struct gpio_chip *gc; int value; - chip = desc->gdev->chip; - offset = gpio_chip_hwgpio(desc); - value = chip->get ? chip->get(chip, offset) : -EIO; + /* FIXME Unable to use gpio_chip_guard due to const desc. */ + gdev = desc->gdev; + + guard(srcu)(&gdev->srcu); + + gc = srcu_dereference(gdev->chip, &gdev->srcu); + if (!gc) + return -ENODEV; + + value = gpio_chip_get_value(gc, desc); value = value < 0 ? value : !!value; trace_gpio_value(desc_to_gpio(desc), 1, value); return value; } -static int gpio_chip_get_multiple(struct gpio_chip *chip, +static int gpio_chip_get_multiple(struct gpio_chip *gc, unsigned long *mask, unsigned long *bits) { - if (chip->get_multiple) { - return chip->get_multiple(chip, mask, bits); - } else if (chip->get) { + lockdep_assert_held(&gc->gpiodev->srcu); + + if (gc->get_multiple) { + int ret; + + ret = gc->get_multiple(gc, mask, bits); + if (ret > 0) + return -EBADE; + return ret; + } + + if (gc->get) { int i, value; - for_each_set_bit(i, mask, chip->ngpio) { - value = chip->get(chip, i); + for_each_set_bit(i, mask, gc->ngpio) { + value = gpiochip_get(gc, i); if (value < 0) return value; __assign_bit(i, bits, value); @@ -2841,13 +3353,22 @@ static int gpio_chip_get_multiple(struct gpio_chip *chip, return -EIO; } +/* The 'other' chip must be protected with its GPIO device's SRCU. */ +static bool gpio_device_chip_cmp(struct gpio_device *gdev, struct gpio_chip *gc) +{ + guard(srcu)(&gdev->srcu); + + return gc == srcu_dereference(gdev->chip, &gdev->srcu); +} + int gpiod_get_array_value_complex(bool raw, bool can_sleep, unsigned int array_size, struct gpio_desc **desc_array, struct gpio_array *array_info, unsigned long *value_bitmap) { - int err, i = 0; + struct gpio_chip *gc; + int ret, i = 0; /* * Validate array_info against desc_array and its size. @@ -2858,53 +3379,67 @@ int gpiod_get_array_value_complex(bool raw, bool can_sleep, array_size <= array_info->size && (void *)array_info == desc_array + array_info->size) { if (!can_sleep) - WARN_ON(array_info->chip->can_sleep); + WARN_ON(array_info->gdev->can_sleep); + + guard(srcu)(&array_info->gdev->srcu); + gc = srcu_dereference(array_info->gdev->chip, + &array_info->gdev->srcu); + if (!gc) + return -ENODEV; - err = gpio_chip_get_multiple(array_info->chip, - array_info->get_mask, + ret = gpio_chip_get_multiple(gc, array_info->get_mask, value_bitmap); - if (err) - return err; + if (ret) + return ret; if (!raw && !bitmap_empty(array_info->invert_mask, array_size)) bitmap_xor(value_bitmap, value_bitmap, array_info->invert_mask, array_size); - if (bitmap_full(array_info->get_mask, array_size)) - return 0; - i = find_first_zero_bit(array_info->get_mask, array_size); + if (i == array_size) + return 0; } else { array_info = NULL; } while (i < array_size) { - struct gpio_chip *chip = desc_array[i]->gdev->chip; - unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)]; + DECLARE_BITMAP(fastpath_mask, FASTPATH_NGPIO); + DECLARE_BITMAP(fastpath_bits, FASTPATH_NGPIO); unsigned long *mask, *bits; - int first, j, ret; + int first, j; - if (likely(chip->ngpio <= FASTPATH_NGPIO)) { - mask = fastpath; + CLASS(gpio_chip_guard, guard)(desc_array[i]); + if (!guard.gc) + return -ENODEV; + + if (likely(guard.gc->ngpio <= FASTPATH_NGPIO)) { + mask = fastpath_mask; + bits = fastpath_bits; } else { - mask = kmalloc_array(2 * BITS_TO_LONGS(chip->ngpio), - sizeof(*mask), - can_sleep ? GFP_KERNEL : GFP_ATOMIC); + gfp_t flags = can_sleep ? GFP_KERNEL : GFP_ATOMIC; + + mask = bitmap_alloc(guard.gc->ngpio, flags); if (!mask) return -ENOMEM; + + bits = bitmap_alloc(guard.gc->ngpio, flags); + if (!bits) { + bitmap_free(mask); + return -ENOMEM; + } } - bits = mask + BITS_TO_LONGS(chip->ngpio); - bitmap_zero(mask, chip->ngpio); + bitmap_zero(mask, guard.gc->ngpio); if (!can_sleep) - WARN_ON(chip->can_sleep); + WARN_ON(guard.gc->can_sleep); /* collect all inputs belonging to the same chip */ first = i; do { const struct gpio_desc *desc = desc_array[i]; - int hwgpio = gpio_chip_hwgpio(desc); + int hwgpio = gpiod_hwgpio(desc); __set_bit(hwgpio, mask); i++; @@ -2913,21 +3448,23 @@ int gpiod_get_array_value_complex(bool raw, bool can_sleep, i = find_next_zero_bit(array_info->get_mask, array_size, i); } while ((i < array_size) && - (desc_array[i]->gdev->chip == chip)); + gpio_device_chip_cmp(desc_array[i]->gdev, guard.gc)); - ret = gpio_chip_get_multiple(chip, mask, bits); + ret = gpio_chip_get_multiple(guard.gc, mask, bits); if (ret) { - if (mask != fastpath) - kfree(mask); + if (mask != fastpath_mask) + bitmap_free(mask); + if (bits != fastpath_bits) + bitmap_free(bits); return ret; } for (j = first; j < i; ) { const struct gpio_desc *desc = desc_array[j]; - int hwgpio = gpio_chip_hwgpio(desc); + int hwgpio = gpiod_hwgpio(desc); int value = test_bit(hwgpio, bits); - if (!raw && test_bit(FLAG_ACTIVE_LOW, &desc->flags)) + if (!raw && test_bit(GPIOD_FLAG_ACTIVE_LOW, &desc->flags)) value = !value; __assign_bit(j, value_bitmap, value); trace_gpio_value(desc_to_gpio(desc), 1, value); @@ -2938,8 +3475,10 @@ int gpiod_get_array_value_complex(bool raw, bool can_sleep, j); } - if (mask != fastpath) - kfree(mask); + if (mask != fastpath_mask) + bitmap_free(mask); + if (bits != fastpath_bits) + bitmap_free(bits); } return 0; } @@ -2948,17 +3487,18 @@ int gpiod_get_array_value_complex(bool raw, bool can_sleep, * gpiod_get_raw_value() - return a gpio's raw value * @desc: gpio whose value will be returned * - * Return the GPIO's raw value, i.e. the value of the physical line disregarding + * Returns: + * The GPIO's raw value, i.e. the value of the physical line disregarding * its ACTIVE_LOW status, or negative errno on failure. * - * This function should be called from contexts where we cannot sleep, and will + * This function can be called from contexts where we cannot sleep, and will * complain if the GPIO chip functions potentially sleep. */ int gpiod_get_raw_value(const struct gpio_desc *desc) { VALIDATE_DESC(desc); - /* Should be using gpio_get_value_cansleep() */ - WARN_ON(desc->gdev->chip->can_sleep); + /* Should be using gpiod_get_raw_value_cansleep() */ + WARN_ON(desc->gdev->can_sleep); return gpiod_get_raw_value_commit(desc); } EXPORT_SYMBOL_GPL(gpiod_get_raw_value); @@ -2967,10 +3507,11 @@ EXPORT_SYMBOL_GPL(gpiod_get_raw_value); * gpiod_get_value() - return a gpio's value * @desc: gpio whose value will be returned * - * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into + * Returns: + * The GPIO's logical value, i.e. taking the ACTIVE_LOW status into * account, or negative errno on failure. * - * This function should be called from contexts where we cannot sleep, and will + * This function can be called from contexts where we cannot sleep, and will * complain if the GPIO chip functions potentially sleep. */ int gpiod_get_value(const struct gpio_desc *desc) @@ -2978,14 +3519,14 @@ int gpiod_get_value(const struct gpio_desc *desc) int value; VALIDATE_DESC(desc); - /* Should be using gpio_get_value_cansleep() */ - WARN_ON(desc->gdev->chip->can_sleep); + /* Should be using gpiod_get_value_cansleep() */ + WARN_ON(desc->gdev->can_sleep); value = gpiod_get_raw_value_commit(desc); if (value < 0) return value; - if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) + if (test_bit(GPIOD_FLAG_ACTIVE_LOW, &desc->flags)) value = !value; return value; @@ -3000,11 +3541,13 @@ EXPORT_SYMBOL_GPL(gpiod_get_value); * @value_bitmap: bitmap to store the read values * * Read the raw values of the GPIOs, i.e. the values of the physical lines - * without regard for their ACTIVE_LOW status. Return 0 in case of success, - * else an error code. + * without regard for their ACTIVE_LOW status. * - * This function should be called from contexts where we cannot sleep, + * This function can be called from contexts where we cannot sleep, * and it will complain if the GPIO chip functions potentially sleep. + * + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_get_raw_array_value(unsigned int array_size, struct gpio_desc **desc_array, @@ -3027,10 +3570,13 @@ EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value); * @value_bitmap: bitmap to store the read values * * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status - * into account. Return 0 in case of success, else an error code. + * into account. * - * This function should be called from contexts where we cannot sleep, + * This function can be called from contexts where we cannot sleep, * and it will complain if the GPIO chip functions potentially sleep. + * + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_get_array_value(unsigned int array_size, struct gpio_desc **desc_array, @@ -3050,26 +3596,28 @@ EXPORT_SYMBOL_GPL(gpiod_get_array_value); * @desc: gpio descriptor whose state need to be set. * @value: Non-zero for setting it HIGH otherwise it will set to LOW. */ -static void gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value) +static int gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value) { - int err = 0; - struct gpio_chip *chip = desc->gdev->chip; - int offset = gpio_chip_hwgpio(desc); + int ret = 0, offset = gpiod_hwgpio(desc); + + CLASS(gpio_chip_guard, guard)(desc); + if (!guard.gc) + return -ENODEV; if (value) { - err = chip->direction_input(chip, offset); - if (!err) - clear_bit(FLAG_IS_OUT, &desc->flags); + ret = gpiochip_direction_input(guard.gc, offset); } else { - err = chip->direction_output(chip, offset, 0); - if (!err) - set_bit(FLAG_IS_OUT, &desc->flags); + ret = gpiochip_direction_output(guard.gc, offset, 0); + if (!ret) + set_bit(GPIOD_FLAG_IS_OUT, &desc->flags); } - trace_gpio_direction(desc_to_gpio(desc), value, err); - if (err < 0) + trace_gpio_direction(desc_to_gpio(desc), value, ret); + if (ret < 0) gpiod_err(desc, "%s: Error in set_value for open drain err %d\n", - __func__, err); + __func__, ret); + + return ret; } /* @@ -3077,58 +3625,79 @@ static void gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value) * @desc: gpio descriptor whose state need to be set. * @value: Non-zero for setting it HIGH otherwise it will set to LOW. */ -static void gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value) +static int gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value) { - int err = 0; - struct gpio_chip *chip = desc->gdev->chip; - int offset = gpio_chip_hwgpio(desc); + int ret = 0, offset = gpiod_hwgpio(desc); + + CLASS(gpio_chip_guard, guard)(desc); + if (!guard.gc) + return -ENODEV; if (value) { - err = chip->direction_output(chip, offset, 1); - if (!err) - set_bit(FLAG_IS_OUT, &desc->flags); + ret = gpiochip_direction_output(guard.gc, offset, 1); + if (!ret) + set_bit(GPIOD_FLAG_IS_OUT, &desc->flags); } else { - err = chip->direction_input(chip, offset); - if (!err) - clear_bit(FLAG_IS_OUT, &desc->flags); + ret = gpiochip_direction_input(guard.gc, offset); } - trace_gpio_direction(desc_to_gpio(desc), !value, err); - if (err < 0) + trace_gpio_direction(desc_to_gpio(desc), !value, ret); + if (ret < 0) gpiod_err(desc, "%s: Error in set_value for open source err %d\n", - __func__, err); + __func__, ret); + + return ret; } -static void gpiod_set_raw_value_commit(struct gpio_desc *desc, bool value) +static int gpiod_set_raw_value_commit(struct gpio_desc *desc, bool value) { - struct gpio_chip *chip; + if (unlikely(!test_bit(GPIOD_FLAG_IS_OUT, &desc->flags))) + return -EPERM; + + CLASS(gpio_chip_guard, guard)(desc); + if (!guard.gc) + return -ENODEV; - chip = desc->gdev->chip; trace_gpio_value(desc_to_gpio(desc), 0, value); - chip->set(chip, gpio_chip_hwgpio(desc), value); + return gpiochip_set(guard.gc, gpiod_hwgpio(desc), value); } /* * set multiple outputs on the same chip; * use the chip's set_multiple function if available; * otherwise set the outputs sequentially; + * @chip: the GPIO chip we operate on * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word * defines which outputs are to be changed * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word * defines the values the outputs specified by mask are to be set to + * + * Returns: 0 on success, negative error number on failure. */ -static void gpio_chip_set_multiple(struct gpio_chip *chip, - unsigned long *mask, unsigned long *bits) +static int gpiochip_set_multiple(struct gpio_chip *gc, + unsigned long *mask, unsigned long *bits) { - if (chip->set_multiple) { - chip->set_multiple(chip, mask, bits); - } else { - unsigned int i; + unsigned int i; + int ret; + + lockdep_assert_held(&gc->gpiodev->srcu); + + if (gc->set_multiple) { + ret = gc->set_multiple(gc, mask, bits); + if (ret > 0) + ret = -EBADE; - /* set outputs if the corresponding mask bit is set */ - for_each_set_bit(i, mask, chip->ngpio) - chip->set(chip, i, test_bit(i, bits)); + return ret; } + + /* set outputs if the corresponding mask bit is set */ + for_each_set_bit(i, mask, gc->ngpio) { + ret = gpiochip_set(gc, i, test_bit(i, bits)); + if (ret) + break; + } + + return ret; } int gpiod_set_array_value_complex(bool raw, bool can_sleep, @@ -3137,7 +3706,8 @@ int gpiod_set_array_value_complex(bool raw, bool can_sleep, struct gpio_array *array_info, unsigned long *value_bitmap) { - int i = 0; + struct gpio_chip *gc; + int i = 0, ret; /* * Validate array_info against desc_array and its size. @@ -3148,50 +3718,76 @@ int gpiod_set_array_value_complex(bool raw, bool can_sleep, array_size <= array_info->size && (void *)array_info == desc_array + array_info->size) { if (!can_sleep) - WARN_ON(array_info->chip->can_sleep); + WARN_ON(array_info->gdev->can_sleep); + + for (i = 0; i < array_size; i++) { + if (unlikely(!test_bit(GPIOD_FLAG_IS_OUT, + &desc_array[i]->flags))) + return -EPERM; + } + + guard(srcu)(&array_info->gdev->srcu); + gc = srcu_dereference(array_info->gdev->chip, + &array_info->gdev->srcu); + if (!gc) + return -ENODEV; if (!raw && !bitmap_empty(array_info->invert_mask, array_size)) bitmap_xor(value_bitmap, value_bitmap, array_info->invert_mask, array_size); - gpio_chip_set_multiple(array_info->chip, array_info->set_mask, - value_bitmap); - - if (bitmap_full(array_info->set_mask, array_size)) - return 0; + ret = gpiochip_set_multiple(gc, array_info->set_mask, + value_bitmap); + if (ret) + return ret; i = find_first_zero_bit(array_info->set_mask, array_size); + if (i == array_size) + return 0; } else { array_info = NULL; } while (i < array_size) { - struct gpio_chip *chip = desc_array[i]->gdev->chip; - unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)]; + DECLARE_BITMAP(fastpath_mask, FASTPATH_NGPIO); + DECLARE_BITMAP(fastpath_bits, FASTPATH_NGPIO); unsigned long *mask, *bits; int count = 0; - if (likely(chip->ngpio <= FASTPATH_NGPIO)) { - mask = fastpath; + CLASS(gpio_chip_guard, guard)(desc_array[i]); + if (!guard.gc) + return -ENODEV; + + if (likely(guard.gc->ngpio <= FASTPATH_NGPIO)) { + mask = fastpath_mask; + bits = fastpath_bits; } else { - mask = kmalloc_array(2 * BITS_TO_LONGS(chip->ngpio), - sizeof(*mask), - can_sleep ? GFP_KERNEL : GFP_ATOMIC); + gfp_t flags = can_sleep ? GFP_KERNEL : GFP_ATOMIC; + + mask = bitmap_alloc(guard.gc->ngpio, flags); if (!mask) return -ENOMEM; + + bits = bitmap_alloc(guard.gc->ngpio, flags); + if (!bits) { + bitmap_free(mask); + return -ENOMEM; + } } - bits = mask + BITS_TO_LONGS(chip->ngpio); - bitmap_zero(mask, chip->ngpio); + bitmap_zero(mask, guard.gc->ngpio); if (!can_sleep) - WARN_ON(chip->can_sleep); + WARN_ON(guard.gc->can_sleep); do { struct gpio_desc *desc = desc_array[i]; - int hwgpio = gpio_chip_hwgpio(desc); + int hwgpio = gpiod_hwgpio(desc); int value = test_bit(i, value_bitmap); + if (unlikely(!test_bit(GPIOD_FLAG_IS_OUT, &desc->flags))) + return -EPERM; + /* * Pins applicable for fast input but not for * fast output processing may have been already @@ -3199,23 +3795,20 @@ int gpiod_set_array_value_complex(bool raw, bool can_sleep, */ if (!raw && !(array_info && test_bit(i, array_info->invert_mask)) && - test_bit(FLAG_ACTIVE_LOW, &desc->flags)) + test_bit(GPIOD_FLAG_ACTIVE_LOW, &desc->flags)) value = !value; trace_gpio_value(desc_to_gpio(desc), 0, value); /* * collect all normal outputs belonging to the same chip * open drain and open source outputs are set individually */ - if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) && !raw) { + if (test_bit(GPIOD_FLAG_OPEN_DRAIN, &desc->flags) && !raw) { gpio_set_open_drain_value_commit(desc, value); - } else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags) && !raw) { + } else if (test_bit(GPIOD_FLAG_OPEN_SOURCE, &desc->flags) && !raw) { gpio_set_open_source_value_commit(desc, value); } else { __set_bit(hwgpio, mask); - if (value) - __set_bit(hwgpio, bits); - else - __clear_bit(hwgpio, bits); + __assign_bit(hwgpio, bits, value); count++; } i++; @@ -3224,13 +3817,18 @@ int gpiod_set_array_value_complex(bool raw, bool can_sleep, i = find_next_zero_bit(array_info->set_mask, array_size, i); } while ((i < array_size) && - (desc_array[i]->gdev->chip == chip)); + gpio_device_chip_cmp(desc_array[i]->gdev, guard.gc)); /* push collected bits to outputs */ - if (count != 0) - gpio_chip_set_multiple(chip, mask, bits); + if (count != 0) { + ret = gpiochip_set_multiple(guard.gc, mask, bits); + if (ret) + return ret; + } - if (mask != fastpath) - kfree(mask); + if (mask != fastpath_mask) + bitmap_free(mask); + if (bits != fastpath_bits) + bitmap_free(bits); } return 0; } @@ -3243,15 +3841,18 @@ int gpiod_set_array_value_complex(bool raw, bool can_sleep, * Set the raw value of the GPIO, i.e. the value of its physical line without * regard for its ACTIVE_LOW status. * - * This function should be called from contexts where we cannot sleep, and will + * This function can be called from contexts where we cannot sleep, and will * complain if the GPIO chip functions potentially sleep. + * + * Returns: + * 0 on success, negative error number on failure. */ -void gpiod_set_raw_value(struct gpio_desc *desc, int value) +int gpiod_set_raw_value(struct gpio_desc *desc, int value) { - VALIDATE_DESC_VOID(desc); - /* Should be using gpiod_set_value_cansleep() */ - WARN_ON(desc->gdev->chip->can_sleep); - gpiod_set_raw_value_commit(desc, value); + VALIDATE_DESC(desc); + /* Should be using gpiod_set_raw_value_cansleep() */ + WARN_ON(desc->gdev->can_sleep); + return gpiod_set_raw_value_commit(desc, value); } EXPORT_SYMBOL_GPL(gpiod_set_raw_value); @@ -3263,17 +3864,21 @@ EXPORT_SYMBOL_GPL(gpiod_set_raw_value); * This sets the value of a GPIO line backing a descriptor, applying * different semantic quirks like active low and open drain/source * handling. + * + * Returns: + * 0 on success, negative error number on failure. */ -static void gpiod_set_value_nocheck(struct gpio_desc *desc, int value) +static int gpiod_set_value_nocheck(struct gpio_desc *desc, int value) { - if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) + if (test_bit(GPIOD_FLAG_ACTIVE_LOW, &desc->flags)) value = !value; - if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) - gpio_set_open_drain_value_commit(desc, value); - else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) - gpio_set_open_source_value_commit(desc, value); - else - gpiod_set_raw_value_commit(desc, value); + + if (test_bit(GPIOD_FLAG_OPEN_DRAIN, &desc->flags)) + return gpio_set_open_drain_value_commit(desc, value); + else if (test_bit(GPIOD_FLAG_OPEN_SOURCE, &desc->flags)) + return gpio_set_open_source_value_commit(desc, value); + + return gpiod_set_raw_value_commit(desc, value); } /** @@ -3284,14 +3889,18 @@ static void gpiod_set_value_nocheck(struct gpio_desc *desc, int value) * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW, * OPEN_DRAIN and OPEN_SOURCE flags into account. * - * This function should be called from contexts where we cannot sleep, and will + * This function can be called from contexts where we cannot sleep, and will * complain if the GPIO chip functions potentially sleep. + * + * Returns: + * 0 on success, negative error number on failure. */ -void gpiod_set_value(struct gpio_desc *desc, int value) +int gpiod_set_value(struct gpio_desc *desc, int value) { - VALIDATE_DESC_VOID(desc); - WARN_ON(desc->gdev->chip->can_sleep); - gpiod_set_value_nocheck(desc, value); + VALIDATE_DESC(desc); + /* Should be using gpiod_set_value_cansleep() */ + WARN_ON(desc->gdev->can_sleep); + return gpiod_set_value_nocheck(desc, value); } EXPORT_SYMBOL_GPL(gpiod_set_value); @@ -3305,8 +3914,11 @@ EXPORT_SYMBOL_GPL(gpiod_set_value); * Set the raw values of the GPIOs, i.e. the values of the physical lines * without regard for their ACTIVE_LOW status. * - * This function should be called from contexts where we cannot sleep, and will + * This function can be called from contexts where we cannot sleep, and will * complain if the GPIO chip functions potentially sleep. + * + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_set_raw_array_value(unsigned int array_size, struct gpio_desc **desc_array, @@ -3330,8 +3942,11 @@ EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value); * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status * into account. * - * This function should be called from contexts where we cannot sleep, and will + * This function can be called from contexts where we cannot sleep, and will * complain if the GPIO chip functions potentially sleep. + * + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_set_array_value(unsigned int array_size, struct gpio_desc **desc_array, @@ -3350,11 +3965,13 @@ EXPORT_SYMBOL_GPL(gpiod_set_array_value); * gpiod_cansleep() - report whether gpio value access may sleep * @desc: gpio to check * + * Returns: + * 0 for non-sleepable, 1 for sleepable, or an error code in case of error. */ int gpiod_cansleep(const struct gpio_desc *desc) { VALIDATE_DESC(desc); - return desc->gdev->chip->can_sleep; + return desc->gdev->can_sleep; } EXPORT_SYMBOL_GPL(gpiod_cansleep); @@ -3362,71 +3979,108 @@ EXPORT_SYMBOL_GPL(gpiod_cansleep); * gpiod_set_consumer_name() - set the consumer name for the descriptor * @desc: gpio to set the consumer name on * @name: the new consumer name + * + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_set_consumer_name(struct gpio_desc *desc, const char *name) { + int ret; + VALIDATE_DESC(desc); - if (name) { - name = kstrdup_const(name, GFP_KERNEL); - if (!name) - return -ENOMEM; - } - kfree_const(desc->label); - desc_set_label(desc, name); + ret = desc_set_label(desc, name); + if (ret == 0) + gpiod_line_state_notify(desc, GPIO_V2_LINE_CHANGED_CONFIG); - return 0; + return ret; } EXPORT_SYMBOL_GPL(gpiod_set_consumer_name); /** + * gpiod_is_shared() - check if this GPIO can be shared by multiple consumers + * @desc: GPIO to inspect + * + * Returns: + * True if this GPIO can be shared by multiple consumers at once. False if it's + * a regular, exclusive GPIO. + * + * Note: + * This function returning true does not mean that this GPIO is currently being + * shared. It means the GPIO core has registered the fact that the firmware + * configuration indicates that it can be shared by multiple consumers and is + * in charge of arbitrating the access. + */ +bool gpiod_is_shared(const struct gpio_desc *desc) +{ + return test_bit(GPIOD_FLAG_SHARED_PROXY, &desc->flags); +} +EXPORT_SYMBOL_GPL(gpiod_is_shared); + +/** * gpiod_to_irq() - return the IRQ corresponding to a GPIO * @desc: gpio whose IRQ will be returned (already requested) * - * Return the IRQ corresponding to the passed GPIO, or an error code in case of - * error. + * Returns: + * The IRQ corresponding to the passed GPIO, or an error code in case of error. */ int gpiod_to_irq(const struct gpio_desc *desc) { - struct gpio_chip *chip; + struct gpio_device *gdev; + struct gpio_chip *gc; int offset; + int ret; - /* - * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics - * requires this function to not return zero on an invalid descriptor - * but rather a negative error number. - */ - if (!desc || IS_ERR(desc) || !desc->gdev || !desc->gdev->chip) + ret = validate_desc(desc, __func__); + if (ret <= 0) return -EINVAL; - chip = desc->gdev->chip; - offset = gpio_chip_hwgpio(desc); - if (chip->to_irq) { - int retirq = chip->to_irq(chip, offset); + gdev = desc->gdev; + /* FIXME Cannot use gpio_chip_guard due to const desc. */ + guard(srcu)(&gdev->srcu); + gc = srcu_dereference(gdev->chip, &gdev->srcu); + if (!gc) + return -ENODEV; - /* Zero means NO_IRQ */ - if (!retirq) - return -ENXIO; + offset = gpiod_hwgpio(desc); + if (gc->to_irq) { + ret = gc->to_irq(gc, offset); + if (ret) + return ret; - return retirq; + /* Zero means NO_IRQ */ + return -ENXIO; } +#ifdef CONFIG_GPIOLIB_IRQCHIP + if (gc->irq.chip) { + /* + * Avoid race condition with other code, which tries to lookup + * an IRQ before the irqchip has been properly registered, + * i.e. while gpiochip is still being brought up. + */ + return -EPROBE_DEFER; + } +#endif return -ENXIO; } EXPORT_SYMBOL_GPL(gpiod_to_irq); /** * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ - * @chip: the chip the GPIO to lock belongs to + * @gc: the chip the GPIO to lock belongs to * @offset: the offset of the GPIO to lock as IRQ * * This is used directly by GPIO drivers that want to lock down * a certain GPIO line to be used for IRQs. + * + * Returns: + * 0 on success, or negative errno on failure. */ -int gpiochip_lock_as_irq(struct gpio_chip *chip, unsigned int offset) +int gpiochip_lock_as_irq(struct gpio_chip *gc, unsigned int offset) { struct gpio_desc *desc; - desc = gpiochip_get_desc(chip, offset); + desc = gpiochip_get_desc(gc, offset); if (IS_ERR(desc)) return PTR_ERR(desc); @@ -3434,33 +4088,27 @@ int gpiochip_lock_as_irq(struct gpio_chip *chip, unsigned int offset) * If it's fast: flush the direction setting if something changed * behind our back */ - if (!chip->can_sleep && chip->get_direction) { + if (!gc->can_sleep && gc->get_direction) { int dir = gpiod_get_direction(desc); if (dir < 0) { - chip_err(chip, "%s: cannot get GPIO direction\n", - __func__); + gpiochip_err(gc, "%s: cannot get GPIO direction\n", + __func__); return dir; } } - if (test_bit(FLAG_IS_OUT, &desc->flags)) { - chip_err(chip, - "%s: tried to flag a GPIO set as output for IRQ\n", - __func__); + /* To be valid for IRQ the line needs to be input or open drain */ + if (test_bit(GPIOD_FLAG_IS_OUT, &desc->flags) && + !test_bit(GPIOD_FLAG_OPEN_DRAIN, &desc->flags)) { + gpiochip_err(gc, + "%s: tried to flag a GPIO set as output for IRQ\n", + __func__); return -EIO; } - set_bit(FLAG_USED_AS_IRQ, &desc->flags); - set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags); - - /* - * If the consumer has not set up a label (such as when the - * IRQ is referenced from .to_irq()) we set up a label here - * so it is clear this is used as an interrupt. - */ - if (!desc->label) - desc_set_label(desc, "interrupt"); + set_bit(GPIOD_FLAG_USED_AS_IRQ, &desc->flags); + set_bit(GPIOD_FLAG_IRQ_IS_ENABLED, &desc->flags); return 0; } @@ -3468,108 +4116,109 @@ EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq); /** * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ - * @chip: the chip the GPIO to lock belongs to + * @gc: the chip the GPIO to lock belongs to * @offset: the offset of the GPIO to lock as IRQ * * This is used directly by GPIO drivers that want to indicate * that a certain GPIO is no longer used exclusively for IRQ. */ -void gpiochip_unlock_as_irq(struct gpio_chip *chip, unsigned int offset) +void gpiochip_unlock_as_irq(struct gpio_chip *gc, unsigned int offset) { struct gpio_desc *desc; - desc = gpiochip_get_desc(chip, offset); + desc = gpiochip_get_desc(gc, offset); if (IS_ERR(desc)) return; - clear_bit(FLAG_USED_AS_IRQ, &desc->flags); - clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags); - - /* If we only had this marking, erase it */ - if (desc->label && !strcmp(desc->label, "interrupt")) - desc_set_label(desc, NULL); + clear_bit(GPIOD_FLAG_USED_AS_IRQ, &desc->flags); + clear_bit(GPIOD_FLAG_IRQ_IS_ENABLED, &desc->flags); } EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq); -void gpiochip_disable_irq(struct gpio_chip *chip, unsigned int offset) +void gpiochip_disable_irq(struct gpio_chip *gc, unsigned int offset) { - struct gpio_desc *desc = gpiochip_get_desc(chip, offset); + struct gpio_desc *desc = gpiochip_get_desc(gc, offset); if (!IS_ERR(desc) && - !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags))) - clear_bit(FLAG_IRQ_IS_ENABLED, &desc->flags); + !WARN_ON(!test_bit(GPIOD_FLAG_USED_AS_IRQ, &desc->flags))) + clear_bit(GPIOD_FLAG_IRQ_IS_ENABLED, &desc->flags); } EXPORT_SYMBOL_GPL(gpiochip_disable_irq); -void gpiochip_enable_irq(struct gpio_chip *chip, unsigned int offset) +void gpiochip_enable_irq(struct gpio_chip *gc, unsigned int offset) { - struct gpio_desc *desc = gpiochip_get_desc(chip, offset); + struct gpio_desc *desc = gpiochip_get_desc(gc, offset); if (!IS_ERR(desc) && - !WARN_ON(!test_bit(FLAG_USED_AS_IRQ, &desc->flags))) { - WARN_ON(test_bit(FLAG_IS_OUT, &desc->flags)); - set_bit(FLAG_IRQ_IS_ENABLED, &desc->flags); + !WARN_ON(!test_bit(GPIOD_FLAG_USED_AS_IRQ, &desc->flags))) { + /* + * We must not be output when using IRQ UNLESS we are + * open drain. + */ + WARN_ON(test_bit(GPIOD_FLAG_IS_OUT, &desc->flags) && + !test_bit(GPIOD_FLAG_OPEN_DRAIN, &desc->flags)); + set_bit(GPIOD_FLAG_IRQ_IS_ENABLED, &desc->flags); } } EXPORT_SYMBOL_GPL(gpiochip_enable_irq); -bool gpiochip_line_is_irq(struct gpio_chip *chip, unsigned int offset) +bool gpiochip_line_is_irq(struct gpio_chip *gc, unsigned int offset) { - if (offset >= chip->ngpio) + if (offset >= gc->ngpio) return false; - return test_bit(FLAG_USED_AS_IRQ, &chip->gpiodev->descs[offset].flags); + return test_bit(GPIOD_FLAG_USED_AS_IRQ, &gc->gpiodev->descs[offset].flags); } EXPORT_SYMBOL_GPL(gpiochip_line_is_irq); -int gpiochip_reqres_irq(struct gpio_chip *chip, unsigned int offset) +int gpiochip_reqres_irq(struct gpio_chip *gc, unsigned int offset) { int ret; - if (!try_module_get(chip->gpiodev->owner)) + if (!try_module_get(gc->gpiodev->owner)) return -ENODEV; - ret = gpiochip_lock_as_irq(chip, offset); + ret = gpiochip_lock_as_irq(gc, offset); if (ret) { - chip_err(chip, "unable to lock HW IRQ %u for IRQ\n", offset); - module_put(chip->gpiodev->owner); + gpiochip_err(gc, "unable to lock HW IRQ %u for IRQ\n", offset); + module_put(gc->gpiodev->owner); return ret; } return 0; } EXPORT_SYMBOL_GPL(gpiochip_reqres_irq); -void gpiochip_relres_irq(struct gpio_chip *chip, unsigned int offset) +void gpiochip_relres_irq(struct gpio_chip *gc, unsigned int offset) { - gpiochip_unlock_as_irq(chip, offset); - module_put(chip->gpiodev->owner); + gpiochip_unlock_as_irq(gc, offset); + module_put(gc->gpiodev->owner); } EXPORT_SYMBOL_GPL(gpiochip_relres_irq); -bool gpiochip_line_is_open_drain(struct gpio_chip *chip, unsigned int offset) +bool gpiochip_line_is_open_drain(struct gpio_chip *gc, unsigned int offset) { - if (offset >= chip->ngpio) + if (offset >= gc->ngpio) return false; - return test_bit(FLAG_OPEN_DRAIN, &chip->gpiodev->descs[offset].flags); + return test_bit(GPIOD_FLAG_OPEN_DRAIN, &gc->gpiodev->descs[offset].flags); } EXPORT_SYMBOL_GPL(gpiochip_line_is_open_drain); -bool gpiochip_line_is_open_source(struct gpio_chip *chip, unsigned int offset) +bool gpiochip_line_is_open_source(struct gpio_chip *gc, unsigned int offset) { - if (offset >= chip->ngpio) + if (offset >= gc->ngpio) return false; - return test_bit(FLAG_OPEN_SOURCE, &chip->gpiodev->descs[offset].flags); + return test_bit(GPIOD_FLAG_OPEN_SOURCE, &gc->gpiodev->descs[offset].flags); } EXPORT_SYMBOL_GPL(gpiochip_line_is_open_source); -bool gpiochip_line_is_persistent(struct gpio_chip *chip, unsigned int offset) +bool gpiochip_line_is_persistent(struct gpio_chip *gc, unsigned int offset) { - if (offset >= chip->ngpio) + if (offset >= gc->ngpio) return false; - return !test_bit(FLAG_TRANSITORY, &chip->gpiodev->descs[offset].flags); + return !test_bit(GPIOD_FLAG_TRANSITORY, &gc->gpiodev->descs[offset].flags); } EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent); @@ -3577,14 +4226,15 @@ EXPORT_SYMBOL_GPL(gpiochip_line_is_persistent); * gpiod_get_raw_value_cansleep() - return a gpio's raw value * @desc: gpio whose value will be returned * - * Return the GPIO's raw value, i.e. the value of the physical line disregarding + * Returns: + * The GPIO's raw value, i.e. the value of the physical line disregarding * its ACTIVE_LOW status, or negative errno on failure. * * This function is to be called from contexts that can sleep. */ int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc) { - might_sleep_if(extra_checks); + might_sleep(); VALIDATE_DESC(desc); return gpiod_get_raw_value_commit(desc); } @@ -3594,7 +4244,8 @@ EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep); * gpiod_get_value_cansleep() - return a gpio's value * @desc: gpio whose value will be returned * - * Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into + * Returns: + * The GPIO's logical value, i.e. taking the ACTIVE_LOW status into * account, or negative errno on failure. * * This function is to be called from contexts that can sleep. @@ -3603,13 +4254,13 @@ int gpiod_get_value_cansleep(const struct gpio_desc *desc) { int value; - might_sleep_if(extra_checks); + might_sleep(); VALIDATE_DESC(desc); value = gpiod_get_raw_value_commit(desc); if (value < 0) return value; - if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) + if (test_bit(GPIOD_FLAG_ACTIVE_LOW, &desc->flags)) value = !value; return value; @@ -3624,17 +4275,19 @@ EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep); * @value_bitmap: bitmap to store the read values * * Read the raw values of the GPIOs, i.e. the values of the physical lines - * without regard for their ACTIVE_LOW status. Return 0 in case of success, - * else an error code. + * without regard for their ACTIVE_LOW status. * * This function is to be called from contexts that can sleep. + * + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_get_raw_array_value_cansleep(unsigned int array_size, struct gpio_desc **desc_array, struct gpio_array *array_info, unsigned long *value_bitmap) { - might_sleep_if(extra_checks); + might_sleep(); if (!desc_array) return -EINVAL; return gpiod_get_array_value_complex(true, true, array_size, @@ -3651,16 +4304,19 @@ EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep); * @value_bitmap: bitmap to store the read values * * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status - * into account. Return 0 in case of success, else an error code. + * into account. * * This function is to be called from contexts that can sleep. + * + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_get_array_value_cansleep(unsigned int array_size, struct gpio_desc **desc_array, struct gpio_array *array_info, unsigned long *value_bitmap) { - might_sleep_if(extra_checks); + might_sleep(); if (!desc_array) return -EINVAL; return gpiod_get_array_value_complex(false, true, array_size, @@ -3678,12 +4334,15 @@ EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep); * regard for its ACTIVE_LOW status. * * This function is to be called from contexts that can sleep. + * + * Returns: + * 0 on success, negative error number on failure. */ -void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value) +int gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value) { - might_sleep_if(extra_checks); - VALIDATE_DESC_VOID(desc); - gpiod_set_raw_value_commit(desc, value); + might_sleep(); + VALIDATE_DESC(desc); + return gpiod_set_raw_value_commit(desc, value); } EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep); @@ -3696,12 +4355,15 @@ EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep); * account * * This function is to be called from contexts that can sleep. + * + * Returns: + * 0 on success, negative error number on failure. */ -void gpiod_set_value_cansleep(struct gpio_desc *desc, int value) +int gpiod_set_value_cansleep(struct gpio_desc *desc, int value) { - might_sleep_if(extra_checks); - VALIDATE_DESC_VOID(desc); - gpiod_set_value_nocheck(desc, value); + might_sleep(); + VALIDATE_DESC(desc); + return gpiod_set_value_nocheck(desc, value); } EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep); @@ -3716,13 +4378,16 @@ EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep); * without regard for their ACTIVE_LOW status. * * This function is to be called from contexts that can sleep. + * + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_set_raw_array_value_cansleep(unsigned int array_size, struct gpio_desc **desc_array, struct gpio_array *array_info, unsigned long *value_bitmap) { - might_sleep_if(extra_checks); + might_sleep(); if (!desc_array) return -EINVAL; return gpiod_set_array_value_complex(true, true, array_size, desc_array, @@ -3739,12 +4404,10 @@ void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n) { unsigned int i; - mutex_lock(&gpio_lookup_lock); + guard(mutex)(&gpio_lookup_lock); for (i = 0; i < n; i++) list_add_tail(&tables[i]->list, &gpio_lookup_list); - - mutex_unlock(&gpio_lookup_lock); } /** @@ -3758,13 +4421,16 @@ void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n) * into account. * * This function is to be called from contexts that can sleep. + * + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_set_array_value_cansleep(unsigned int array_size, struct gpio_desc **desc_array, struct gpio_array *array_info, unsigned long *value_bitmap) { - might_sleep_if(extra_checks); + might_sleep(); if (!desc_array) return -EINVAL; return gpiod_set_array_value_complex(false, true, array_size, @@ -3773,17 +4439,20 @@ int gpiod_set_array_value_cansleep(unsigned int array_size, } EXPORT_SYMBOL_GPL(gpiod_set_array_value_cansleep); +void gpiod_line_state_notify(struct gpio_desc *desc, unsigned long action) +{ + guard(read_lock_irqsave)(&desc->gdev->line_state_lock); + + raw_notifier_call_chain(&desc->gdev->line_state_notifier, action, desc); +} + /** * gpiod_add_lookup_table() - register GPIO device consumers * @table: table of consumers to register */ void gpiod_add_lookup_table(struct gpiod_lookup_table *table) { - mutex_lock(&gpio_lookup_lock); - - list_add_tail(&table->list, &gpio_lookup_list); - - mutex_unlock(&gpio_lookup_lock); + gpiod_add_lookup_tables(&table, 1); } EXPORT_SYMBOL_GPL(gpiod_add_lookup_table); @@ -3793,11 +4462,13 @@ EXPORT_SYMBOL_GPL(gpiod_add_lookup_table); */ void gpiod_remove_lookup_table(struct gpiod_lookup_table *table) { - mutex_lock(&gpio_lookup_lock); + /* Nothing to remove */ + if (!table) + return; - list_del(&table->list); + guard(mutex)(&gpio_lookup_lock); - mutex_unlock(&gpio_lookup_lock); + list_del(&table->list); } EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table); @@ -3807,10 +4478,9 @@ EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table); */ void gpiod_add_hogs(struct gpiod_hog *hogs) { - struct gpio_chip *chip; struct gpiod_hog *hog; - mutex_lock(&gpio_machine_hogs_mutex); + guard(mutex)(&gpio_machine_hogs_mutex); for (hog = &hogs[0]; hog->chip_label; hog++) { list_add_tail(&hog->list, &gpio_machine_hogs); @@ -3819,22 +4489,30 @@ void gpiod_add_hogs(struct gpiod_hog *hogs) * The chip may have been registered earlier, so check if it * exists and, if so, try to hog the line now. */ - chip = find_chip_by_name(hog->chip_label); - if (chip) - gpiochip_machine_hog(chip, hog); + struct gpio_device *gdev __free(gpio_device_put) = + gpio_device_find_by_label(hog->chip_label); + if (gdev) + gpiochip_machine_hog(gpio_device_get_chip(gdev), hog); } - - mutex_unlock(&gpio_machine_hogs_mutex); } EXPORT_SYMBOL_GPL(gpiod_add_hogs); +void gpiod_remove_hogs(struct gpiod_hog *hogs) +{ + struct gpiod_hog *hog; + + guard(mutex)(&gpio_machine_hogs_mutex); + + for (hog = &hogs[0]; hog->chip_label; hog++) + list_del(&hog->list); +} +EXPORT_SYMBOL_GPL(gpiod_remove_hogs); + static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev) { const char *dev_id = dev ? dev_name(dev) : NULL; struct gpiod_lookup_table *table; - mutex_lock(&gpio_lookup_lock); - list_for_each_entry(table, &gpio_lookup_list, list) { if (table->dev_id && dev_id) { /* @@ -3842,38 +4520,35 @@ static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev) * a match */ if (!strcmp(table->dev_id, dev_id)) - goto found; + return table; } else { /* * One of the pointers is NULL, so both must be to have * a match */ if (dev_id == table->dev_id) - goto found; + return table; } } - table = NULL; -found: - mutex_unlock(&gpio_lookup_lock); - return table; + return NULL; } static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id, - unsigned int idx, - enum gpio_lookup_flags *flags) + unsigned int idx, unsigned long *flags) { struct gpio_desc *desc = ERR_PTR(-ENOENT); struct gpiod_lookup_table *table; struct gpiod_lookup *p; + struct gpio_chip *gc; + + guard(mutex)(&gpio_lookup_lock); table = gpiod_find_lookup_table(dev); if (!table) return desc; - for (p = &table->table[0]; p->chip_label; p++) { - struct gpio_chip *chip; - + for (p = &table->table[0]; p->key; p++) { /* idx must always match exactly */ if (p->idx != idx) continue; @@ -3882,29 +4557,44 @@ static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id, if (p->con_id && (!con_id || strcmp(p->con_id, con_id))) continue; - chip = find_chip_by_name(p->chip_label); + if (p->chip_hwnum == U16_MAX) { + desc = gpio_name_to_desc(p->key); + if (desc) { + *flags = p->flags; + return desc; + } - if (!chip) { + dev_warn(dev, "cannot find GPIO line %s, deferring\n", + p->key); + return ERR_PTR(-EPROBE_DEFER); + } + + struct gpio_device *gdev __free(gpio_device_put) = + gpio_device_find_by_label(p->key); + if (!gdev) { /* * As the lookup table indicates a chip with - * p->chip_label should exist, assume it may + * p->key should exist, assume it may * still appear later and let the interested * consumer be probed again or let the Deferred * Probe infrastructure handle the error. */ dev_warn(dev, "cannot find GPIO chip %s, deferring\n", - p->chip_label); + p->key); return ERR_PTR(-EPROBE_DEFER); } - if (chip->ngpio <= p->chip_hwnum) { + gc = gpio_device_get_chip(gdev); + + if (gc->ngpio <= p->chip_hwnum) { dev_err(dev, - "requested GPIO %d is out of range [0..%d] for chip %s\n", - idx, chip->ngpio, chip->label); + "requested GPIO %u (%u) is out of range [0..%u] for chip %s\n", + idx, p->chip_hwnum, gc->ngpio - 1, + gc->label); return ERR_PTR(-EINVAL); } - desc = gpiochip_get_desc(chip, p->chip_hwnum); + desc = gpio_device_get_desc(gdev, p->chip_hwnum); *flags = p->flags; return desc; @@ -3913,62 +4603,215 @@ static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id, return desc; } -static int dt_gpio_count(struct device *dev, const char *con_id) -{ - int ret; - char propname[32]; - unsigned int i; - - for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) { - if (con_id) - snprintf(propname, sizeof(propname), "%s-%s", - con_id, gpio_suffixes[i]); - else - snprintf(propname, sizeof(propname), "%s", - gpio_suffixes[i]); - - ret = of_gpio_named_count(dev->of_node, propname); - if (ret > 0) - break; - } - return ret ? ret : -ENOENT; -} - static int platform_gpio_count(struct device *dev, const char *con_id) { struct gpiod_lookup_table *table; struct gpiod_lookup *p; unsigned int count = 0; - table = gpiod_find_lookup_table(dev); - if (!table) - return -ENOENT; + scoped_guard(mutex, &gpio_lookup_lock) { + table = gpiod_find_lookup_table(dev); + if (!table) + return -ENOENT; - for (p = &table->table[0]; p->chip_label; p++) { - if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) || - (!con_id && !p->con_id)) - count++; + for (p = &table->table[0]; p->key; p++) { + if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) || + (!con_id && !p->con_id)) + count++; + } } + if (!count) return -ENOENT; return count; } +static struct gpio_desc *gpiod_find_by_fwnode(struct fwnode_handle *fwnode, + struct device *consumer, + const char *con_id, + unsigned int idx, + enum gpiod_flags *flags, + unsigned long *lookupflags) +{ + const char *name = function_name_or_default(con_id); + struct gpio_desc *desc = ERR_PTR(-ENOENT); + + if (is_of_node(fwnode)) { + dev_dbg(consumer, "using DT '%pfw' for '%s' GPIO lookup\n", fwnode, name); + desc = of_find_gpio(to_of_node(fwnode), con_id, idx, lookupflags); + } else if (is_acpi_node(fwnode)) { + dev_dbg(consumer, "using ACPI '%pfw' for '%s' GPIO lookup\n", fwnode, name); + desc = acpi_find_gpio(fwnode, con_id, idx, flags, lookupflags); + } else if (is_software_node(fwnode)) { + dev_dbg(consumer, "using swnode '%pfw' for '%s' GPIO lookup\n", fwnode, name); + desc = swnode_find_gpio(fwnode, con_id, idx, lookupflags); + } + + return desc; +} + +static struct gpio_desc *gpiod_fwnode_lookup(struct fwnode_handle *fwnode, + struct device *consumer, + const char *con_id, + unsigned int idx, + enum gpiod_flags *flags, + unsigned long *lookupflags) +{ + struct gpio_desc *desc; + + desc = gpiod_find_by_fwnode(fwnode, consumer, con_id, idx, flags, lookupflags); + if (gpiod_not_found(desc) && !IS_ERR_OR_NULL(fwnode)) + desc = gpiod_find_by_fwnode(fwnode->secondary, consumer, con_id, + idx, flags, lookupflags); + + return desc; +} + +struct gpio_desc *gpiod_find_and_request(struct device *consumer, + struct fwnode_handle *fwnode, + const char *con_id, + unsigned int idx, + enum gpiod_flags flags, + const char *label, + bool platform_lookup_allowed) +{ + unsigned long lookupflags = GPIO_LOOKUP_FLAGS_DEFAULT; + const char *name = function_name_or_default(con_id); + /* + * scoped_guard() is implemented as a for loop, meaning static + * analyzers will complain about these two not being initialized. + */ + struct gpio_desc *desc = NULL; + int ret = 0; + + scoped_guard(srcu, &gpio_devices_srcu) { + desc = gpiod_fwnode_lookup(fwnode, consumer, con_id, idx, + &flags, &lookupflags); + if (!IS_ERR_OR_NULL(desc) && + test_bit(GPIOD_FLAG_SHARED, &desc->flags)) { + /* + * We're dealing with a GPIO shared by multiple + * consumers. This is the moment to add the machine + * lookup table for the proxy device as previously + * we only knew the consumer's fwnode. + */ + ret = gpio_shared_add_proxy_lookup(consumer, lookupflags); + if (ret) + return ERR_PTR(ret); + + /* Trigger platform lookup for shared GPIO proxy. */ + desc = ERR_PTR(-ENOENT); + /* Trigger it even for fwnode-only gpiod_get(). */ + platform_lookup_allowed = true; + } + + if (gpiod_not_found(desc) && platform_lookup_allowed) { + /* + * Either we are not using DT or ACPI, or their lookup + * did not return a result or this is a shared GPIO. In + * that case, use platform lookup as a fallback. + */ + dev_dbg(consumer, + "using lookup tables for GPIO lookup\n"); + desc = gpiod_find(consumer, con_id, idx, &lookupflags); + } + + if (IS_ERR(desc)) { + dev_dbg(consumer, "No GPIO consumer %s found\n", name); + return desc; + } + + /* + * If a connection label was passed use that, else attempt to use + * the device name as label + */ + ret = gpiod_request(desc, label); + } + if (ret) { + if (!(ret == -EBUSY && flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE)) + return ERR_PTR(ret); + + /* + * This happens when there are several consumers for the same + * GPIO line: we just return here without further + * initialization. It's a hack introduced long ago to support + * fixed regulators. We now have a better solution with + * automated scanning where affected platforms just need to + * select the provided Kconfig option. + * + * FIXME: Remove the GPIOD_FLAGS_BIT_NONEXCLUSIVE flag after + * making sure all platforms use the new mechanism. + */ + dev_info(consumer, + "nonexclusive access to GPIO for %s, consider updating your code to using gpio-shared-proxy\n", + name); + return desc; + } + + ret = gpiod_configure_flags(desc, con_id, lookupflags, flags); + if (ret < 0) { + gpiod_put(desc); + dev_err(consumer, "setup of GPIO %s failed: %d\n", name, ret); + return ERR_PTR(ret); + } + + gpiod_line_state_notify(desc, GPIO_V2_LINE_CHANGED_REQUESTED); + + return desc; +} + +/** + * fwnode_gpiod_get_index - obtain a GPIO from firmware node + * @fwnode: handle of the firmware node + * @con_id: function within the GPIO consumer + * @index: index of the GPIO to obtain for the consumer + * @flags: GPIO initialization flags + * @label: label to attach to the requested GPIO + * + * This function can be used for drivers that get their configuration + * from opaque firmware. + * + * The function properly finds the corresponding GPIO using whatever is the + * underlying firmware interface and then makes sure that the GPIO + * descriptor is requested before it is returned to the caller. + * + * Returns: + * On successful request the GPIO pin is configured in accordance with + * provided @flags. + * + * In case of error an ERR_PTR() is returned. + */ +struct gpio_desc *fwnode_gpiod_get_index(struct fwnode_handle *fwnode, + const char *con_id, + int index, + enum gpiod_flags flags, + const char *label) +{ + return gpiod_find_and_request(NULL, fwnode, con_id, index, flags, label, false); +} +EXPORT_SYMBOL_GPL(fwnode_gpiod_get_index); + /** * gpiod_count - return the number of GPIOs associated with a device / function - * or -ENOENT if no GPIO has been assigned to the requested function * @dev: GPIO consumer, can be NULL for system-global GPIOs * @con_id: function within the GPIO consumer + * + * Returns: + * The number of GPIOs associated with a device / function or -ENOENT if no + * GPIO has been assigned to the requested function. */ int gpiod_count(struct device *dev, const char *con_id) { + const struct fwnode_handle *fwnode = dev ? dev_fwnode(dev) : NULL; int count = -ENOENT; - if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node) - count = dt_gpio_count(dev, con_id); - else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev)) - count = acpi_gpio_count(dev, con_id); + if (is_of_node(fwnode)) + count = of_gpio_count(fwnode, con_id); + else if (is_acpi_node(fwnode)) + count = acpi_gpio_count(fwnode, con_id); + else if (is_software_node(fwnode)) + count = swnode_gpio_count(fwnode, con_id); if (count < 0) count = platform_gpio_count(dev, con_id); @@ -3983,7 +4826,8 @@ EXPORT_SYMBOL_GPL(gpiod_count); * @con_id: function within the GPIO consumer * @flags: optional GPIO initialization flags * - * Return the GPIO descriptor corresponding to the function con_id of device + * Returns: + * The GPIO descriptor corresponding to the function @con_id of device * dev, -ENOENT if no GPIO has been assigned to the requested function, or * another IS_ERR() code if an error occurred while trying to acquire the GPIO. */ @@ -4003,6 +4847,11 @@ EXPORT_SYMBOL_GPL(gpiod_get); * This is equivalent to gpiod_get(), except that when no GPIO was assigned to * the requested function it will return NULL. This is convenient for drivers * that need to handle optional GPIOs. + * + * Returns: + * The GPIO descriptor corresponding to the function @con_id of device + * dev, NULL if no GPIO has been assigned to the requested function, or + * another IS_ERR() code if an error occurred while trying to acquire the GPIO. */ struct gpio_desc *__must_check gpiod_get_optional(struct device *dev, const char *con_id, @@ -4017,24 +4866,26 @@ EXPORT_SYMBOL_GPL(gpiod_get_optional); * gpiod_configure_flags - helper function to configure a given GPIO * @desc: gpio whose value will be assigned * @con_id: function within the GPIO consumer - * @lflags: gpio_lookup_flags - returned from of_find_gpio() or - * of_get_gpio_hog() + * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from + * of_find_gpio() or of_get_gpio_hog() * @dflags: gpiod_flags - optional GPIO initialization flags * - * Return 0 on success, -ENOENT if no GPIO has been assigned to the + * Returns: + * 0 on success, -ENOENT if no GPIO has been assigned to the * requested function and/or index, or another IS_ERR() code if an error * occurred while trying to acquire the GPIO. */ int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id, unsigned long lflags, enum gpiod_flags dflags) { - int status; + const char *name = function_name_or_default(con_id); + int ret; if (lflags & GPIO_ACTIVE_LOW) - set_bit(FLAG_ACTIVE_LOW, &desc->flags); + set_bit(GPIOD_FLAG_ACTIVE_LOW, &desc->flags); if (lflags & GPIO_OPEN_DRAIN) - set_bit(FLAG_OPEN_DRAIN, &desc->flags); + set_bit(GPIOD_FLAG_OPEN_DRAIN, &desc->flags); else if (dflags & GPIOD_FLAGS_BIT_OPEN_DRAIN) { /* * This enforces open drain mode from the consumer side. @@ -4042,32 +4893,47 @@ int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id, * should *REALLY* have specified them as open drain in the * first place, so print a little warning here. */ - set_bit(FLAG_OPEN_DRAIN, &desc->flags); + set_bit(GPIOD_FLAG_OPEN_DRAIN, &desc->flags); gpiod_warn(desc, "enforced open drain please flag it properly in DT/ACPI DSDT/board file\n"); } if (lflags & GPIO_OPEN_SOURCE) - set_bit(FLAG_OPEN_SOURCE, &desc->flags); + set_bit(GPIOD_FLAG_OPEN_SOURCE, &desc->flags); - status = gpiod_set_transitory(desc, (lflags & GPIO_TRANSITORY)); - if (status < 0) - return status; + if (((lflags & GPIO_PULL_UP) && (lflags & GPIO_PULL_DOWN)) || + ((lflags & GPIO_PULL_UP) && (lflags & GPIO_PULL_DISABLE)) || + ((lflags & GPIO_PULL_DOWN) && (lflags & GPIO_PULL_DISABLE))) { + gpiod_err(desc, + "multiple pull-up, pull-down or pull-disable enabled, invalid configuration\n"); + return -EINVAL; + } + + if (lflags & GPIO_PULL_UP) + set_bit(GPIOD_FLAG_PULL_UP, &desc->flags); + else if (lflags & GPIO_PULL_DOWN) + set_bit(GPIOD_FLAG_PULL_DOWN, &desc->flags); + else if (lflags & GPIO_PULL_DISABLE) + set_bit(GPIOD_FLAG_BIAS_DISABLE, &desc->flags); + + ret = gpiod_set_transitory(desc, (lflags & GPIO_TRANSITORY)); + if (ret < 0) + return ret; /* No particular flag request, return here... */ if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) { - pr_debug("no flags found for %s\n", con_id); + gpiod_dbg(desc, "no flags found for GPIO %s\n", name); return 0; } /* Process flags */ if (dflags & GPIOD_FLAGS_BIT_DIR_OUT) - status = gpiod_direction_output(desc, + ret = gpiod_direction_output_nonotify(desc, !!(dflags & GPIOD_FLAGS_BIT_DIR_VAL)); else - status = gpiod_direction_input(desc); + ret = gpiod_direction_input_nonotify(desc); - return status; + return ret; } /** @@ -4080,7 +4946,8 @@ int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id, * This variant of gpiod_get() allows to access GPIOs other than the first * defined one for functions that define several GPIOs. * - * Return a valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the + * Returns: + * A valid GPIO descriptor, -ENOENT if no GPIO has been assigned to the * requested function and/or index, or another IS_ERR() code if an error * occurred while trying to acquire the GPIO. */ @@ -4089,214 +4956,15 @@ struct gpio_desc *__must_check gpiod_get_index(struct device *dev, unsigned int idx, enum gpiod_flags flags) { - struct gpio_desc *desc = NULL; - int status; - enum gpio_lookup_flags lookupflags = 0; - /* Maybe we have a device name, maybe not */ + struct fwnode_handle *fwnode = dev ? dev_fwnode(dev) : NULL; const char *devname = dev ? dev_name(dev) : "?"; + const char *label = con_id ?: devname; - dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id); - - if (dev) { - /* Using device tree? */ - if (IS_ENABLED(CONFIG_OF) && dev->of_node) { - dev_dbg(dev, "using device tree for GPIO lookup\n"); - desc = of_find_gpio(dev, con_id, idx, &lookupflags); - } else if (ACPI_COMPANION(dev)) { - dev_dbg(dev, "using ACPI for GPIO lookup\n"); - desc = acpi_find_gpio(dev, con_id, idx, &flags, &lookupflags); - } - } - - /* - * Either we are not using DT or ACPI, or their lookup did not return - * a result. In that case, use platform lookup as a fallback. - */ - if (!desc || desc == ERR_PTR(-ENOENT)) { - dev_dbg(dev, "using lookup tables for GPIO lookup\n"); - desc = gpiod_find(dev, con_id, idx, &lookupflags); - } - - if (IS_ERR(desc)) { - dev_dbg(dev, "No GPIO consumer %s found\n", con_id); - return desc; - } - - /* - * If a connection label was passed use that, else attempt to use - * the device name as label - */ - status = gpiod_request(desc, con_id ? con_id : devname); - if (status < 0) { - if (status == -EBUSY && flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE) { - /* - * This happens when there are several consumers for - * the same GPIO line: we just return here without - * further initialization. It is a bit if a hack. - * This is necessary to support fixed regulators. - * - * FIXME: Make this more sane and safe. - */ - dev_info(dev, "nonexclusive access to GPIO for %s\n", - con_id ? con_id : devname); - return desc; - } else { - return ERR_PTR(status); - } - } - - status = gpiod_configure_flags(desc, con_id, lookupflags, flags); - if (status < 0) { - dev_dbg(dev, "setup of GPIO %s failed\n", con_id); - gpiod_put(desc); - return ERR_PTR(status); - } - - return desc; + return gpiod_find_and_request(dev, fwnode, con_id, idx, flags, label, true); } EXPORT_SYMBOL_GPL(gpiod_get_index); /** - * gpiod_get_from_of_node() - obtain a GPIO from an OF node - * @node: handle of the OF node - * @propname: name of the DT property representing the GPIO - * @index: index of the GPIO to obtain for the consumer - * @dflags: GPIO initialization flags - * @label: label to attach to the requested GPIO - * - * Returns: - * On successful request the GPIO pin is configured in accordance with - * provided @dflags. If the node does not have the requested GPIO - * property, NULL is returned. - * - * In case of error an ERR_PTR() is returned. - */ -struct gpio_desc *gpiod_get_from_of_node(struct device_node *node, - const char *propname, int index, - enum gpiod_flags dflags, - const char *label) -{ - struct gpio_desc *desc; - unsigned long lflags = 0; - enum of_gpio_flags flags; - bool active_low = false; - bool single_ended = false; - bool open_drain = false; - bool transitory = false; - int ret; - - desc = of_get_named_gpiod_flags(node, propname, - index, &flags); - - if (!desc || IS_ERR(desc)) { - /* If it is not there, just return NULL */ - if (PTR_ERR(desc) == -ENOENT) - return NULL; - return desc; - } - - active_low = flags & OF_GPIO_ACTIVE_LOW; - single_ended = flags & OF_GPIO_SINGLE_ENDED; - open_drain = flags & OF_GPIO_OPEN_DRAIN; - transitory = flags & OF_GPIO_TRANSITORY; - - ret = gpiod_request(desc, label); - if (ret == -EBUSY && (flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE)) - return desc; - if (ret) - return ERR_PTR(ret); - - if (active_low) - lflags |= GPIO_ACTIVE_LOW; - - if (single_ended) { - if (open_drain) - lflags |= GPIO_OPEN_DRAIN; - else - lflags |= GPIO_OPEN_SOURCE; - } - - if (transitory) - lflags |= GPIO_TRANSITORY; - - ret = gpiod_configure_flags(desc, propname, lflags, dflags); - if (ret < 0) { - gpiod_put(desc); - return ERR_PTR(ret); - } - - return desc; -} -EXPORT_SYMBOL(gpiod_get_from_of_node); - -/** - * fwnode_get_named_gpiod - obtain a GPIO from firmware node - * @fwnode: handle of the firmware node - * @propname: name of the firmware property representing the GPIO - * @index: index of the GPIO to obtain for the consumer - * @dflags: GPIO initialization flags - * @label: label to attach to the requested GPIO - * - * This function can be used for drivers that get their configuration - * from opaque firmware. - * - * The function properly finds the corresponding GPIO using whatever is the - * underlying firmware interface and then makes sure that the GPIO - * descriptor is requested before it is returned to the caller. - * - * Returns: - * On successful request the GPIO pin is configured in accordance with - * provided @dflags. - * - * In case of error an ERR_PTR() is returned. - */ -struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode, - const char *propname, int index, - enum gpiod_flags dflags, - const char *label) -{ - struct gpio_desc *desc = ERR_PTR(-ENODEV); - unsigned long lflags = 0; - int ret; - - if (!fwnode) - return ERR_PTR(-EINVAL); - - if (is_of_node(fwnode)) { - desc = gpiod_get_from_of_node(to_of_node(fwnode), - propname, index, - dflags, - label); - return desc; - } else if (is_acpi_node(fwnode)) { - struct acpi_gpio_info info; - - desc = acpi_node_get_gpiod(fwnode, propname, index, &info); - if (IS_ERR(desc)) - return desc; - - acpi_gpio_update_gpiod_flags(&dflags, &info); - - if (info.polarity == GPIO_ACTIVE_LOW) - lflags |= GPIO_ACTIVE_LOW; - } - - /* Currently only ACPI takes this path */ - ret = gpiod_request(desc, label); - if (ret) - return ERR_PTR(ret); - - ret = gpiod_configure_flags(desc, propname, lflags, dflags); - if (ret < 0) { - gpiod_put(desc); - return ERR_PTR(ret); - } - - return desc; -} -EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod); - -/** * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO * function * @dev: GPIO consumer, can be NULL for system-global GPIOs @@ -4307,6 +4975,11 @@ EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod); * This is equivalent to gpiod_get_index(), except that when no GPIO with the * specified index was assigned to the requested function it will return NULL. * This is convenient for drivers that need to handle optional GPIOs. + * + * Returns: + * A valid GPIO descriptor, NULL if no GPIO has been assigned to the + * requested function and/or index, or another IS_ERR() code if an error + * occurred while trying to acquire the GPIO. */ struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev, const char *con_id, @@ -4316,10 +4989,8 @@ struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev, struct gpio_desc *desc; desc = gpiod_get_index(dev, con_id, index, flags); - if (IS_ERR(desc)) { - if (PTR_ERR(desc) == -ENOENT) - return NULL; - } + if (gpiod_not_found(desc)) + return NULL; return desc; } @@ -4329,71 +5000,58 @@ EXPORT_SYMBOL_GPL(gpiod_get_index_optional); * gpiod_hog - Hog the specified GPIO desc given the provided flags * @desc: gpio whose value will be assigned * @name: gpio line name - * @lflags: gpio_lookup_flags - returned from of_find_gpio() or - * of_get_gpio_hog() + * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from + * of_find_gpio() or of_get_gpio_hog() * @dflags: gpiod_flags - optional GPIO initialization flags + * + * Returns: + * 0 on success, or negative errno on failure. */ int gpiod_hog(struct gpio_desc *desc, const char *name, unsigned long lflags, enum gpiod_flags dflags) { - struct gpio_chip *chip; + struct gpio_device *gdev = desc->gdev; struct gpio_desc *local_desc; int hwnum; - int status; + int ret; - chip = gpiod_to_chip(desc); - hwnum = gpio_chip_hwgpio(desc); + CLASS(gpio_chip_guard, guard)(desc); + if (!guard.gc) + return -ENODEV; - /* - * FIXME: not very elegant that we call gpiod_configure_flags() - * twice here (once inside gpiochip_request_own_desc() and - * again here), but the gpiochip_request_own_desc() is external - * and cannot really pass the lflags so this is the lesser evil - * at the moment. Pass zero as dflags on this first call so we - * don't screw anything up. - */ - local_desc = gpiochip_request_own_desc(chip, hwnum, name, 0); + if (test_and_set_bit(GPIOD_FLAG_IS_HOGGED, &desc->flags)) + return 0; + + hwnum = gpiod_hwgpio(desc); + + local_desc = gpiochip_request_own_desc(guard.gc, hwnum, name, + lflags, dflags); if (IS_ERR(local_desc)) { - status = PTR_ERR(local_desc); + clear_bit(GPIOD_FLAG_IS_HOGGED, &desc->flags); + ret = PTR_ERR(local_desc); pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n", - name, chip->label, hwnum, status); - return status; - } - - status = gpiod_configure_flags(desc, name, lflags, dflags); - if (status < 0) { - pr_err("setup of hog GPIO %s (chip %s, offset %d) failed, %d\n", - name, chip->label, hwnum, status); - gpiochip_free_own_desc(desc); - return status; + name, gdev->label, hwnum, ret); + return ret; } - /* Mark GPIO as hogged so it can be identified and removed later */ - set_bit(FLAG_IS_HOGGED, &desc->flags); - - pr_info("GPIO line %d (%s) hogged as %s%s\n", - desc_to_gpio(desc), name, - (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input", - (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ? - (dflags&GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low":""); + gpiod_dbg(desc, "hogged as %s/%s\n", + (dflags & GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input", + (dflags & GPIOD_FLAGS_BIT_DIR_OUT) ? + str_high_low(dflags & GPIOD_FLAGS_BIT_DIR_VAL) : "?"); return 0; } /** * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog - * @chip: gpio chip to act on - * - * This is only used by of_gpiochip_remove to free hogged gpios + * @gc: gpio chip to act on */ -static void gpiochip_free_hogs(struct gpio_chip *chip) +static void gpiochip_free_hogs(struct gpio_chip *gc) { - int id; + struct gpio_desc *desc; - for (id = 0; id < chip->ngpio; id++) { - if (test_bit(FLAG_IS_HOGGED, &chip->gpiodev->descs[id].flags)) - gpiochip_free_own_desc(&chip->gpiodev->descs[id]); - } + for_each_gpio_desc_with_flag(gc, desc, GPIOD_FLAG_IS_HOGGED) + gpiochip_free_own_desc(desc); } /** @@ -4404,9 +5062,11 @@ static void gpiochip_free_hogs(struct gpio_chip *chip) * * This function acquires all the GPIOs defined under a given function. * - * Return a struct gpio_descs containing an array of descriptors, -ENOENT if - * no GPIO has been assigned to the requested function, or another IS_ERR() - * code if an error occurred while trying to acquire the GPIOs. + * Returns: + * The GPIO descriptors corresponding to the function @con_id of device + * dev, -ENOENT if no GPIO has been assigned to the requested function, + * or another IS_ERR() code if an error occurred while trying to acquire + * the GPIOs. */ struct gpio_descs *__must_check gpiod_get_array(struct device *dev, const char *con_id, @@ -4414,19 +5074,22 @@ struct gpio_descs *__must_check gpiod_get_array(struct device *dev, { struct gpio_desc *desc; struct gpio_descs *descs; + struct gpio_device *gdev; struct gpio_array *array_info = NULL; - struct gpio_chip *chip; int count, bitmap_size; + unsigned long dflags; + size_t descs_size; count = gpiod_count(dev, con_id); if (count < 0) return ERR_PTR(count); - descs = kzalloc(struct_size(descs, desc, count), GFP_KERNEL); + descs_size = struct_size(descs, desc, count); + descs = kzalloc(descs_size, GFP_KERNEL); if (!descs) return ERR_PTR(-ENOMEM); - for (descs->ndescs = 0; descs->ndescs < count; ) { + for (descs->ndescs = 0; descs->ndescs < count; descs->ndescs++) { desc = gpiod_get_index(dev, con_id, descs->ndescs, flags); if (IS_ERR(desc)) { gpiod_put_array(descs); @@ -4435,31 +5098,28 @@ struct gpio_descs *__must_check gpiod_get_array(struct device *dev, descs->desc[descs->ndescs] = desc; - chip = gpiod_to_chip(desc); + gdev = gpiod_to_gpio_device(desc); /* * If pin hardware number of array member 0 is also 0, select * its chip as a candidate for fast bitmap processing path. */ - if (descs->ndescs == 0 && gpio_chip_hwgpio(desc) == 0) { + if (descs->ndescs == 0 && gpiod_hwgpio(desc) == 0) { struct gpio_descs *array; - bitmap_size = BITS_TO_LONGS(chip->ngpio > count ? - chip->ngpio : count); + bitmap_size = BITS_TO_LONGS(gdev->ngpio > count ? + gdev->ngpio : count); - array = kzalloc(struct_size(descs, desc, count) + - struct_size(array_info, invert_mask, - 3 * bitmap_size), GFP_KERNEL); + array = krealloc(descs, descs_size + + struct_size(array_info, invert_mask, 3 * bitmap_size), + GFP_KERNEL | __GFP_ZERO); if (!array) { gpiod_put_array(descs); return ERR_PTR(-ENOMEM); } - memcpy(array, descs, - struct_size(descs, desc, descs->ndescs + 1)); - kfree(descs); - descs = array; - array_info = (void *)(descs->desc + count); + + array_info = (void *)descs + descs_size; array_info->get_mask = array_info->invert_mask + bitmap_size; array_info->set_mask = array_info->get_mask + @@ -4467,15 +5127,20 @@ struct gpio_descs *__must_check gpiod_get_array(struct device *dev, array_info->desc = descs->desc; array_info->size = count; - array_info->chip = chip; + array_info->gdev = gdev; bitmap_set(array_info->get_mask, descs->ndescs, count - descs->ndescs); bitmap_set(array_info->set_mask, descs->ndescs, count - descs->ndescs); descs->info = array_info; } + + /* If there is no cache for fast bitmap processing path, continue */ + if (!array_info) + continue; + /* Unmark array members which don't belong to the 'fast' chip */ - if (array_info && array_info->chip != chip) { + if (array_info->gdev != gdev) { __clear_bit(descs->ndescs, array_info->get_mask); __clear_bit(descs->ndescs, array_info->set_mask); } @@ -4483,8 +5148,7 @@ struct gpio_descs *__must_check gpiod_get_array(struct device *dev, * Detect array members which belong to the 'fast' chip * but their pins are not in hardware order. */ - else if (array_info && - gpio_chip_hwgpio(desc) != descs->ndescs) { + else if (gpiod_hwgpio(desc) != descs->ndescs) { /* * Don't use fast path if all array members processed so * far belong to the same chip as this one but its pin @@ -4498,10 +5162,11 @@ struct gpio_descs *__must_check gpiod_get_array(struct device *dev, __clear_bit(descs->ndescs, array_info->set_mask); } - } else if (array_info) { + } else { + dflags = READ_ONCE(desc->flags); /* Exclude open drain or open source from fast output */ - if (gpiochip_line_is_open_drain(chip, descs->ndescs) || - gpiochip_line_is_open_source(chip, descs->ndescs)) + if (test_bit(GPIOD_FLAG_OPEN_DRAIN, &dflags) || + test_bit(GPIOD_FLAG_OPEN_SOURCE, &dflags)) __clear_bit(descs->ndescs, array_info->set_mask); /* Identify 'fast' pins which require invertion */ @@ -4509,13 +5174,11 @@ struct gpio_descs *__must_check gpiod_get_array(struct device *dev, __set_bit(descs->ndescs, array_info->invert_mask); } - - descs->ndescs++; } if (array_info) dev_dbg(dev, "GPIO array info: chip=%s, size=%d, get_mask=%lx, set_mask=%lx, invert_mask=%lx\n", - array_info->chip->label, array_info->size, + array_info->gdev->label, array_info->size, *array_info->get_mask, *array_info->set_mask, *array_info->invert_mask); return descs; @@ -4531,6 +5194,12 @@ EXPORT_SYMBOL_GPL(gpiod_get_array); * * This is equivalent to gpiod_get_array(), except that when no GPIO was * assigned to the requested function it will return NULL. + * + * Returns: + * The GPIO descriptors corresponding to the function @con_id of device + * dev, NULL if no GPIO has been assigned to the requested function, + * or another IS_ERR() code if an error occurred while trying to acquire + * the GPIOs. */ struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev, const char *con_id, @@ -4539,7 +5208,7 @@ struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev, struct gpio_descs *descs; descs = gpiod_get_array(dev, con_id, flags); - if (IS_ERR(descs) && (PTR_ERR(descs) == -ENOENT)) + if (gpiod_not_found(descs)) return NULL; return descs; @@ -4573,6 +5242,29 @@ void gpiod_put_array(struct gpio_descs *descs) } EXPORT_SYMBOL_GPL(gpiod_put_array); +static int gpio_stub_drv_probe(struct device *dev) +{ + /* + * The DT node of some GPIO chips have a "compatible" property, but + * never have a struct device added and probed by a driver to register + * the GPIO chip with gpiolib. In such cases, fw_devlink=on will cause + * the consumers of the GPIO chip to get probe deferred forever because + * they will be waiting for a device associated with the GPIO chip + * firmware node to get added and bound to a driver. + * + * To allow these consumers to probe, we associate the struct + * gpio_device of the GPIO chip with the firmware node and then simply + * bind it to this stub driver. + */ + return 0; +} + +static struct device_driver gpio_stub_drv = { + .name = "gpio_stub_drv", + .bus = &gpio_bus_type, + .probe = gpio_stub_drv_probe, +}; + static int __init gpiolib_dev_init(void) { int ret; @@ -4584,14 +5276,28 @@ static int __init gpiolib_dev_init(void) return ret; } - ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, "gpiochip"); + ret = driver_register(&gpio_stub_drv); + if (ret < 0) { + pr_err("gpiolib: could not register GPIO stub driver\n"); + bus_unregister(&gpio_bus_type); + return ret; + } + + ret = alloc_chrdev_region(&gpio_devt, 0, GPIO_DEV_MAX, GPIOCHIP_NAME); if (ret < 0) { pr_err("gpiolib: failed to allocate char dev region\n"); + driver_unregister(&gpio_stub_drv); bus_unregister(&gpio_bus_type); - } else { - gpiolib_initialized = true; - gpiochip_setup_devs(); + return ret; } + + gpiolib_initialized = true; + gpiochip_setup_devs(); + +#if IS_ENABLED(CONFIG_OF_DYNAMIC) && IS_ENABLED(CONFIG_OF_GPIO) + WARN_ON(of_reconfig_notifier_register(&gpio_of_notifier)); +#endif /* CONFIG_OF_DYNAMIC && CONFIG_OF_GPIO */ + return ret; } core_initcall(gpiolib_dev_init); @@ -4600,138 +5306,150 @@ core_initcall(gpiolib_dev_init); static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev) { - unsigned i; - struct gpio_chip *chip = gdev->chip; - unsigned gpio = gdev->base; - struct gpio_desc *gdesc = &gdev->descs[0]; - bool is_out; - bool is_irq; - bool active_low; - - for (i = 0; i < gdev->ngpio; i++, gpio++, gdesc++) { - if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) { - if (gdesc->name) { - seq_printf(s, " gpio-%-3d (%-20.20s)\n", - gpio, gdesc->name); - } - continue; + bool active_low, is_irq, is_out; + struct gpio_desc *desc; + unsigned int gpio = 0; + struct gpio_chip *gc; + unsigned long flags; + int value; + + guard(srcu)(&gdev->srcu); + + gc = srcu_dereference(gdev->chip, &gdev->srcu); + if (!gc) { + seq_puts(s, "Underlying GPIO chip is gone\n"); + return; + } + + for_each_gpio_desc(gc, desc) { + guard(srcu)(&desc->gdev->desc_srcu); + flags = READ_ONCE(desc->flags); + is_irq = test_bit(GPIOD_FLAG_USED_AS_IRQ, &flags); + if (is_irq || test_bit(GPIOD_FLAG_REQUESTED, &flags)) { + gpiod_get_direction(desc); + is_out = test_bit(GPIOD_FLAG_IS_OUT, &flags); + value = gpio_chip_get_value(gc, desc); + active_low = test_bit(GPIOD_FLAG_ACTIVE_LOW, &flags); + seq_printf(s, " gpio-%-3u (%-20.20s|%-20.20s) %s %s %s%s\n", + gpio, desc->name ?: "", gpiod_get_label(desc), + is_out ? "out" : "in ", + value >= 0 ? str_hi_lo(value) : "? ", + is_irq ? "IRQ " : "", + active_low ? "ACTIVE LOW" : ""); + } else if (desc->name) { + seq_printf(s, " gpio-%-3u (%-20.20s)\n", gpio, desc->name); } - gpiod_get_direction(gdesc); - is_out = test_bit(FLAG_IS_OUT, &gdesc->flags); - is_irq = test_bit(FLAG_USED_AS_IRQ, &gdesc->flags); - active_low = test_bit(FLAG_ACTIVE_LOW, &gdesc->flags); - seq_printf(s, " gpio-%-3d (%-20.20s|%-20.20s) %s %s %s%s", - gpio, gdesc->name ? gdesc->name : "", gdesc->label, - is_out ? "out" : "in ", - chip->get ? (chip->get(chip, i) ? "hi" : "lo") : "? ", - is_irq ? "IRQ " : "", - active_low ? "ACTIVE LOW" : ""); - seq_printf(s, "\n"); + gpio++; } } +struct gpiolib_seq_priv { + bool newline; + int idx; +}; + static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos) { - unsigned long flags; - struct gpio_device *gdev = NULL; + struct gpiolib_seq_priv *priv; + struct gpio_device *gdev; loff_t index = *pos; - s->private = ""; + s->private = NULL; + + priv = kzalloc(sizeof(*priv), GFP_KERNEL); + if (!priv) + return NULL; + + s->private = priv; + if (*pos > 0) + priv->newline = true; + priv->idx = srcu_read_lock(&gpio_devices_srcu); - spin_lock_irqsave(&gpio_lock, flags); - list_for_each_entry(gdev, &gpio_devices, list) - if (index-- == 0) { - spin_unlock_irqrestore(&gpio_lock, flags); + list_for_each_entry_srcu(gdev, &gpio_devices, list, + srcu_read_lock_held(&gpio_devices_srcu)) { + if (index-- == 0) return gdev; - } - spin_unlock_irqrestore(&gpio_lock, flags); + } return NULL; } static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos) { - unsigned long flags; - struct gpio_device *gdev = v; - void *ret = NULL; + struct gpiolib_seq_priv *priv = s->private; + struct gpio_device *gdev = v, *next; - spin_lock_irqsave(&gpio_lock, flags); - if (list_is_last(&gdev->list, &gpio_devices)) - ret = NULL; - else - ret = list_entry(gdev->list.next, struct gpio_device, list); - spin_unlock_irqrestore(&gpio_lock, flags); - - s->private = "\n"; + next = list_entry_rcu(gdev->list.next, struct gpio_device, list); + gdev = &next->list == &gpio_devices ? NULL : next; + priv->newline = true; ++*pos; - return ret; + return gdev; } static void gpiolib_seq_stop(struct seq_file *s, void *v) { + struct gpiolib_seq_priv *priv; + + priv = s->private; + if (!priv) + return; + + srcu_read_unlock(&gpio_devices_srcu, priv->idx); + kfree(priv); } static int gpiolib_seq_show(struct seq_file *s, void *v) { + struct gpiolib_seq_priv *priv = s->private; struct gpio_device *gdev = v; - struct gpio_chip *chip = gdev->chip; + struct gpio_chip *gc; struct device *parent; - if (!chip) { - seq_printf(s, "%s%s: (dangling chip)", (char *)s->private, - dev_name(&gdev->dev)); + if (priv->newline) + seq_putc(s, '\n'); + + guard(srcu)(&gdev->srcu); + + gc = srcu_dereference(gdev->chip, &gdev->srcu); + if (!gc) { + seq_printf(s, "%s: (dangling chip)\n", dev_name(&gdev->dev)); return 0; } - seq_printf(s, "%s%s: GPIOs %d-%d", (char *)s->private, - dev_name(&gdev->dev), - gdev->base, gdev->base + gdev->ngpio - 1); - parent = chip->parent; + seq_printf(s, "%s: %u GPIOs", dev_name(&gdev->dev), gdev->ngpio); + parent = gc->parent; if (parent) seq_printf(s, ", parent: %s/%s", parent->bus ? parent->bus->name : "no-bus", dev_name(parent)); - if (chip->label) - seq_printf(s, ", %s", chip->label); - if (chip->can_sleep) + if (gc->label) + seq_printf(s, ", %s", gc->label); + if (gc->can_sleep) seq_printf(s, ", can sleep"); seq_printf(s, ":\n"); - if (chip->dbg_show) - chip->dbg_show(s, chip); + if (gc->dbg_show) + gc->dbg_show(s, gc); else gpiolib_dbg_show(s, gdev); return 0; } -static const struct seq_operations gpiolib_seq_ops = { +static const struct seq_operations gpiolib_sops = { .start = gpiolib_seq_start, .next = gpiolib_seq_next, .stop = gpiolib_seq_stop, .show = gpiolib_seq_show, }; - -static int gpiolib_open(struct inode *inode, struct file *file) -{ - return seq_open(file, &gpiolib_seq_ops); -} - -static const struct file_operations gpiolib_operations = { - .owner = THIS_MODULE, - .open = gpiolib_open, - .read = seq_read, - .llseek = seq_lseek, - .release = seq_release, -}; +DEFINE_SEQ_ATTRIBUTE(gpiolib); static int __init gpiolib_debugfs_init(void) { /* /sys/kernel/debug/gpio */ - (void) debugfs_create_file("gpio", S_IFREG | S_IRUGO, - NULL, NULL, &gpiolib_operations); + debugfs_create_file("gpio", 0444, NULL, NULL, &gpiolib_fops); return 0; } subsys_initcall(gpiolib_debugfs_init); |