diff options
Diffstat (limited to 'drivers/gpio/gpiolib.c')
| -rw-r--r-- | drivers/gpio/gpiolib.c | 6209 |
1 files changed, 4749 insertions, 1460 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index ff0fd655729f..91e0c384f34a 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -1,204 +1,366 @@ -#include <linux/kernel.h> -#include <linux/module.h> +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/acpi.h> +#include <linux/array_size.h> +#include <linux/bitmap.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/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 <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 #include <trace/events/gpio.h> -/* Optional implementation infrastructure for GPIO interfaces. - * - * Platforms may want to use this if they tend to use very many GPIOs - * that aren't part of a System-On-Chip core; or across I2C/SPI/etc. +/* Implementation infrastructure for GPIO interfaces. * - * When kernel footprint or instruction count is an issue, simpler - * implementations may be preferred. The GPIO programming interface - * allows for inlining speed-critical get/set operations for common - * cases, so that access to SOC-integrated GPIOs can sometimes cost - * only an instruction or two per bit. + * The GPIO programming interface allows for inlining speed-critical + * get/set operations for common cases, so that access to SOC-integrated + * GPIOs can sometimes cost only an instruction or two per bit. */ +/* 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 */ -/* 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. +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, +}; + +/* + * 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. */ -#ifdef DEBUG -#define extra_checks 1 -#else -#define extra_checks 0 -#endif +#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 */ -static DEFINE_SPINLOCK(gpio_lock); +#define FASTPATH_NGPIO CONFIG_GPIOLIB_FASTPATH_LIMIT -struct gpio_desc { - struct gpio_chip *chip; - unsigned long flags; -/* flag symbols are bit numbers */ -#define FLAG_REQUESTED 0 -#define FLAG_IS_OUT 1 -#define FLAG_EXPORT 2 /* protected by sysfs_lock */ -#define FLAG_SYSFS 3 /* exported via /sys/class/gpio/control */ -#define FLAG_TRIG_FALL 4 /* trigger on falling edge */ -#define FLAG_TRIG_RISE 5 /* trigger on rising edge */ -#define FLAG_ACTIVE_LOW 6 /* sysfs value has active low */ -#define FLAG_OPEN_DRAIN 7 /* Gpio is open drain type */ -#define FLAG_OPEN_SOURCE 8 /* Gpio is open source type */ +static DEFINE_MUTEX(gpio_lookup_lock); +static LIST_HEAD(gpio_lookup_list); -#define ID_SHIFT 16 /* add new flags before this one */ +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); -#define GPIO_FLAGS_MASK ((1 << ID_SHIFT) - 1) -#define GPIO_TRIGGER_MASK (BIT(FLAG_TRIG_FALL) | BIT(FLAG_TRIG_RISE)) +static DEFINE_MUTEX(gpio_machine_hogs_mutex); +static LIST_HEAD(gpio_machine_hogs); -#ifdef CONFIG_DEBUG_FS - const char *label; -#endif -}; -static struct gpio_desc gpio_desc[ARCH_NR_GPIOS]; +const char *const gpio_suffixes[] = { "gpios", "gpio", NULL }; -#define GPIO_OFFSET_VALID(chip, offset) (offset >= 0 && offset < chip->ngpio) +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 *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 LIST_HEAD(gpio_chips); +static bool gpiolib_initialized; -#ifdef CONFIG_GPIO_SYSFS -static DEFINE_IDR(dirent_idr); -#endif +const char *gpiod_get_label(struct gpio_desc *desc) +{ + struct gpio_desc_label *label; + unsigned long flags; -/* - * Internal gpiod_* API using descriptors instead of the integer namespace. - * Most of this should eventually go public. - */ -static int gpiod_request(struct gpio_desc *desc, const char *label); -static void gpiod_free(struct gpio_desc *desc); -static int gpiod_direction_input(struct gpio_desc *desc); -static int gpiod_direction_output(struct gpio_desc *desc, int value); -static int gpiod_get_direction(const struct gpio_desc *desc); -static int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce); -static int gpiod_get_value_cansleep(const struct gpio_desc *desc); -static void gpiod_set_value_cansleep(struct gpio_desc *desc, int value); -static int gpiod_get_value(const struct gpio_desc *desc); -static void gpiod_set_value(struct gpio_desc *desc, int value); -static int gpiod_cansleep(const struct gpio_desc *desc); -static int gpiod_to_irq(const struct gpio_desc *desc); -static int gpiod_export(struct gpio_desc *desc, bool direction_may_change); -static int gpiod_export_link(struct device *dev, const char *name, - struct gpio_desc *desc); -static int gpiod_sysfs_set_active_low(struct gpio_desc *desc, int value); -static void gpiod_unexport(struct gpio_desc *desc); - - -static inline void desc_set_label(struct gpio_desc *d, const char *label) + 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) { -#ifdef CONFIG_DEBUG_FS - d->label = label; -#endif + kfree(container_of(rh, struct gpio_desc_label, rh)); } -/* - * Return the GPIO number of the passed descriptor relative to its chip +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; +} + +/** + * gpio_to_desc - Convert a GPIO number to its descriptor + * @gpio: global GPIO number + * + * Returns: + * The GPIO descriptor associated with the given GPIO, or %NULL if no GPIO + * with the given number exists in the system. */ -static int gpio_chip_hwgpio(const struct gpio_desc *desc) +struct gpio_desc *gpio_to_desc(unsigned gpio) { - return desc - &desc->chip->desc[0]; + struct gpio_device *gdev; + + 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]; + } + } + + 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); } /** - * Convert a GPIO number to its descriptor + * 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 %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. */ -static struct gpio_desc *gpio_to_desc(unsigned gpio) +struct gpio_desc * +gpio_device_get_desc(struct gpio_device *gdev, unsigned int hwnum) { - if (WARN(!gpio_is_valid(gpio), "invalid GPIO %d\n", gpio)) - return NULL; - else - return &gpio_desc[gpio]; + if (hwnum >= gdev->ngpio) + return ERR_PTR(-EINVAL); + + return &gdev->descs[array_index_nospec(hwnum, gdev->ngpio)]; } +EXPORT_SYMBOL_GPL(gpio_device_get_desc); /** - * Convert a GPIO descriptor to the integer namespace. + * desc_to_gpio - convert a GPIO descriptor to the integer namespace + * @desc: GPIO descriptor + * * This should disappear in the future but is needed since we still - * use GPIO numbers for error messages and sysfs nodes + * use GPIO numbers for error messages and sysfs nodes. + * + * Returns: + * The global GPIO number for the GPIO specified by its descriptor. */ -static int desc_to_gpio(const struct gpio_desc *desc) +int desc_to_gpio(const struct gpio_desc *desc) { - return desc->chip->base + gpio_chip_hwgpio(desc); + return desc->gdev->base + (desc - &desc->gdev->descs[0]); } +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); -/* Warn when drivers omit gpio_request() calls -- legal but ill-advised - * when setting direction, and otherwise illegal. Until board setup code - * and drivers use explicit requests everywhere (which won't happen when - * those calls have no teeth) we can't avoid autorequesting. This nag - * message should motivate switching to explicit requests... so should - * the weaker cleanup after faults, compared to gpio_request(). +/** + * 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. * - * NOTE: the autorequest mechanism is going away; at this point it's - * only "legal" in the sense that (old) code using it won't break yet, - * but instead only triggers a WARN() stack dump. + * Returns: + * Address of the GPIO chip backing this device. */ -static int gpio_ensure_requested(struct gpio_desc *desc) +struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc) { - const struct gpio_chip *chip = desc->chip; - const int gpio = desc_to_gpio(desc); + if (!desc) + return NULL; - if (WARN(test_and_set_bit(FLAG_REQUESTED, &desc->flags) == 0, - "autorequest GPIO-%d\n", gpio)) { - if (!try_module_get(chip->owner)) { - pr_err("GPIO-%d: module can't be gotten \n", gpio); - clear_bit(FLAG_REQUESTED, &desc->flags); - /* lose */ - return -EIO; - } - desc_set_label(desc, "[auto]"); - /* caller must chip->request() w/o spinlock */ - if (chip->request) - return 1; - } - return 0; + 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); -static struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc) +/** + * 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 desc ? desc->chip : NULL; + return gdev->base; } +EXPORT_SYMBOL_GPL(gpio_device_get_base); -/* caller holds gpio_lock *OR* gpio is marked as requested */ -struct gpio_chip *gpio_to_chip(unsigned gpio) +/** + * 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 gpiod_to_chip(gpio_to_desc(gpio)); + 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) { - struct gpio_chip *chip; - int base = ARCH_NR_GPIOS - ngpio; + unsigned int base = GPIO_DYNAMIC_BASE; + struct gpio_device *gdev; - list_for_each_entry_reverse(chip, &gpio_chips, list) { + list_for_each_entry_srcu(gdev, &gpio_devices, list, + lockdep_is_held(&gpio_devices_lock)) { /* found a free space? */ - if (chip->base + chip->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 = chip->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 { @@ -207,1177 +369,2079 @@ static int gpiochip_find_base(int ngpio) } } -/* caller ensures gpio is valid and requested, chip->get_direction may sleep */ -static int gpiod_get_direction(const struct gpio_desc *desc) +/* + * 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) { - struct gpio_chip *chip; - unsigned offset; - int status = -EINVAL; - - chip = gpiod_to_chip(desc); - offset = gpio_chip_hwgpio(desc); - - if (!chip->get_direction) - return status; + if (!desc) + return 0; - status = chip->get_direction(chip, offset); - if (status > 0) { - /* GPIOF_DIR_IN, or other positive */ - status = 1; - /* FLAG_IS_OUT is just a cache of the result of get_direction(), - * so it does not affect constness per se */ - clear_bit(FLAG_IS_OUT, &((struct gpio_desc *)desc)->flags); + if (IS_ERR(desc)) { + pr_warn("%s: invalid GPIO (errorpointer: %pe)\n", func, desc); + return PTR_ERR(desc); } - if (status == 0) { - /* GPIOF_DIR_OUT */ - set_bit(FLAG_IS_OUT, &((struct gpio_desc *)desc)->flags); - } - return status; + + return 1; } -#ifdef CONFIG_GPIO_SYSFS +#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) -/* lock protects against unexport_gpio() being called while - * sysfs files are active. +/** + * 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. */ -static DEFINE_MUTEX(sysfs_lock); +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); -/* - * /sys/class/gpio/gpioN... only for GPIOs that are exported - * /direction - * * MAY BE OMITTED if kernel won't allow direction changes - * * is read/write as "in" or "out" - * * may also be written as "high" or "low", initializing - * output value as specified ("out" implies "low") - * /value - * * always readable, subject to hardware behavior - * * may be writable, as zero/nonzero - * /edge - * * configures behavior of poll(2) on /value - * * available only if pin can generate IRQs on input - * * is read/write as "none", "falling", "rising", or "both" - * /active_low - * * configures polarity of /value - * * is read/write as zero/nonzero - * * also affects existing and subsequent "falling" and "rising" - * /edge configuration - */ - -static ssize_t gpio_direction_show(struct device *dev, - struct device_attribute *attr, char *buf) -{ - const struct gpio_desc *desc = dev_get_drvdata(dev); - ssize_t status; - - mutex_lock(&sysfs_lock); - - if (!test_bit(FLAG_EXPORT, &desc->flags)) { - status = -EIO; - } else { - gpiod_get_direction(desc); - status = sprintf(buf, "%s\n", - test_bit(FLAG_IS_OUT, &desc->flags) - ? "out" : "in"); - } +static int gpiochip_get_direction(struct gpio_chip *gc, unsigned int offset) +{ + int ret; - mutex_unlock(&sysfs_lock); - return status; + 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; } -static ssize_t gpio_direction_store(struct device *dev, - struct device_attribute *attr, const char *buf, size_t size) +/** + * 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. + * + * This function may sleep if gpiod_cansleep() is true. + */ +int gpiod_get_direction(struct gpio_desc *desc) { - struct gpio_desc *desc = dev_get_drvdata(dev); - ssize_t status; + unsigned long flags; + unsigned int offset; + int ret; - mutex_lock(&sysfs_lock); + ret = validate_desc(desc, __func__); + if (ret <= 0) + return -EINVAL; - if (!test_bit(FLAG_EXPORT, &desc->flags)) - status = -EIO; - else if (sysfs_streq(buf, "high")) - status = gpiod_direction_output(desc, 1); - else if (sysfs_streq(buf, "out") || sysfs_streq(buf, "low")) - status = gpiod_direction_output(desc, 0); - else if (sysfs_streq(buf, "in")) - status = gpiod_direction_input(desc); - else - status = -EINVAL; + CLASS(gpio_chip_guard, guard)(desc); + if (!guard.gc) + return -ENODEV; - mutex_unlock(&sysfs_lock); - return status ? : size; -} + 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; -static /* const */ DEVICE_ATTR(direction, 0644, - gpio_direction_show, gpio_direction_store); + if (!guard.gc->get_direction) + return -ENOTSUPP; + + 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); -static ssize_t gpio_value_show(struct device *dev, - struct device_attribute *attr, char *buf) +/* + * Add a new chip to the global chips list, keeping the list of chips sorted + * by range(means [base, base + ngpio - 1]) order. + * + * Returns: + * -EBUSY if the new chip overlaps with some other chip's integer space. + */ +static int gpiodev_add_to_list_unlocked(struct gpio_device *gdev) { - struct gpio_desc *desc = dev_get_drvdata(dev); - ssize_t status; + struct gpio_device *prev, *next; - mutex_lock(&sysfs_lock); + lockdep_assert_held(&gpio_devices_lock); - if (!test_bit(FLAG_EXPORT, &desc->flags)) { - status = -EIO; - } else { - int value; + if (list_empty(&gpio_devices)) { + /* initial entry in list */ + list_add_tail_rcu(&gdev->list, &gpio_devices); + return 0; + } - value = !!gpiod_get_value_cansleep(desc); - if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) - value = !value; + next = list_first_entry(&gpio_devices, struct gpio_device, list); + if (gdev->base + gdev->ngpio <= next->base) { + /* add before first entry */ + list_add_rcu(&gdev->list, &gpio_devices); + return 0; + } - status = sprintf(buf, "%d\n", value); + prev = list_last_entry(&gpio_devices, struct gpio_device, list); + if (prev->base + prev->ngpio <= gdev->base) { + /* add behind last entry */ + list_add_tail_rcu(&gdev->list, &gpio_devices); + return 0; } - mutex_unlock(&sysfs_lock); - return status; + list_for_each_entry_safe(prev, next, &gpio_devices, list) { + /* at the end of the list */ + if (&next->list == &gpio_devices) + break; + + /* add between prev and next */ + if (prev->base + prev->ngpio <= gdev->base + && gdev->base + gdev->ngpio <= next->base) { + list_add_rcu(&gdev->list, &prev->list); + return 0; + } + } + + synchronize_srcu(&gpio_devices_srcu); + + return -EBUSY; } -static ssize_t gpio_value_store(struct device *dev, - struct device_attribute *attr, const char *buf, size_t size) +/* + * 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_desc *desc = dev_get_drvdata(dev); - ssize_t status; + struct gpio_device *gdev; + struct gpio_desc *desc; + struct gpio_chip *gc; - mutex_lock(&sysfs_lock); + if (!name) + return NULL; - if (!test_bit(FLAG_EXPORT, &desc->flags)) - status = -EIO; - else if (!test_bit(FLAG_IS_OUT, &desc->flags)) - status = -EPERM; - else { - long value; + guard(srcu)(&gpio_devices_srcu); - status = strict_strtol(buf, 0, &value); - if (status == 0) { - if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) - value = !value; - gpiod_set_value_cansleep(desc, value != 0); - status = size; + list_for_each_entry_srcu(gdev, &gpio_devices, list, + srcu_read_lock_held(&gpio_devices_srcu)) { + guard(srcu)(&gdev->srcu); + + gc = srcu_dereference(gdev->chip, &gdev->srcu); + if (!gc) + continue; + + for_each_gpio_desc(gc, desc) { + if (desc->name && !strcmp(desc->name, name)) + return desc; } } - mutex_unlock(&sysfs_lock); - return status; + return NULL; } -static const DEVICE_ATTR(value, 0644, - gpio_value_show, gpio_value_store); - -static irqreturn_t gpio_sysfs_irq(int irq, void *priv) +/* + * 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. + * + * Note that: + * 1. Non-unique names are still accepted, + * 2. Name collisions within the same GPIO chip are not reported. + */ +static void gpiochip_set_desc_names(struct gpio_chip *gc) { - struct sysfs_dirent *value_sd = priv; + struct gpio_device *gdev = gc->gpiodev; + int i; + + /* First check all names if they are unique */ + for (i = 0; i != gc->ngpio; ++i) { + struct gpio_desc *gpio; + + gpio = gpio_name_to_desc(gc->names[i]); + if (gpio) + dev_warn(&gdev->dev, + "Detected name collision for GPIO name '%s'\n", + gc->names[i]); + } - sysfs_notify_dirent(value_sd); - return IRQ_HANDLED; + /* Then add all names to the GPIO descriptors */ + for (i = 0; i != gc->ngpio; ++i) + gdev->descs[i].name = gc->names[i]; } -static int gpio_setup_irq(struct gpio_desc *desc, struct device *dev, - unsigned long gpio_flags) +/* + * 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) { - struct sysfs_dirent *value_sd; - unsigned long irq_flags; - int ret, irq, id; - - if ((desc->flags & GPIO_TRIGGER_MASK) == gpio_flags) + struct gpio_device *gdev = chip->gpiodev; + struct device *dev = &gdev->dev; + const char **names; + int ret, i; + int count; + + count = device_property_string_array_count(dev, "gpio-line-names"); + if (count < 0) return 0; - irq = gpiod_to_irq(desc); - if (irq < 0) - return -EIO; + /* + * 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; + } - id = desc->flags >> ID_SHIFT; - value_sd = idr_find(&dirent_idr, id); - if (value_sd) - free_irq(irq, value_sd); + names = kcalloc(count, sizeof(*names), GFP_KERNEL); + if (!names) + return -ENOMEM; - desc->flags &= ~GPIO_TRIGGER_MASK; + 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; + } - if (!gpio_flags) { - ret = 0; - goto free_id; - } - - irq_flags = IRQF_SHARED; - if (test_bit(FLAG_TRIG_FALL, &gpio_flags)) - irq_flags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ? - IRQF_TRIGGER_RISING : IRQF_TRIGGER_FALLING; - if (test_bit(FLAG_TRIG_RISE, &gpio_flags)) - irq_flags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ? - IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING; - - if (!value_sd) { - value_sd = sysfs_get_dirent(dev->kobj.sd, NULL, "value"); - if (!value_sd) { - ret = -ENODEV; - goto err_out; - } + /* + * 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; + + 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]; + } - ret = idr_alloc(&dirent_idr, value_sd, 1, 0, GFP_KERNEL); - if (ret < 0) - goto free_sd; - id = ret; + kfree(names); - desc->flags &= GPIO_FLAGS_MASK; - desc->flags |= (unsigned long)id << ID_SHIFT; + return 0; +} - if (desc->flags >> ID_SHIFT != id) { - ret = -ERANGE; - goto free_id; - } - } +static unsigned long *gpiochip_allocate_mask(struct gpio_chip *gc) +{ + unsigned long *p; - ret = request_any_context_irq(irq, gpio_sysfs_irq, irq_flags, - "gpiolib", value_sd); - if (ret < 0) - goto free_id; + p = bitmap_alloc(gc->ngpio, GFP_KERNEL); + if (!p) + return NULL; - desc->flags |= gpio_flags; - return 0; + /* Assume by default all GPIOs are valid */ + bitmap_fill(p, gc->ngpio); -free_id: - idr_remove(&dirent_idr, id); - desc->flags &= GPIO_FLAGS_MASK; -free_sd: - if (value_sd) - sysfs_put(value_sd); -err_out: - return ret; + return p; } -static const struct { - const char *name; - unsigned long flags; -} trigger_types[] = { - { "none", 0 }, - { "falling", BIT(FLAG_TRIG_FALL) }, - { "rising", BIT(FLAG_TRIG_RISE) }, - { "both", BIT(FLAG_TRIG_FALL) | BIT(FLAG_TRIG_RISE) }, -}; - -static ssize_t gpio_edge_show(struct device *dev, - struct device_attribute *attr, char *buf) +static void gpiochip_free_mask(unsigned long **p) { - const struct gpio_desc *desc = dev_get_drvdata(dev); - ssize_t status; - - mutex_lock(&sysfs_lock); + bitmap_free(*p); + *p = NULL; +} - if (!test_bit(FLAG_EXPORT, &desc->flags)) - status = -EIO; - else { - int i; +static unsigned int gpiochip_count_reserved_ranges(struct gpio_chip *gc) +{ + struct device *dev = &gc->gpiodev->dev; + int size; - status = 0; - for (i = 0; i < ARRAY_SIZE(trigger_types); i++) - if ((desc->flags & GPIO_TRIGGER_MASK) - == trigger_types[i].flags) { - status = sprintf(buf, "%s\n", - trigger_types[i].name); - break; - } - } + /* Format is "start, count, ..." */ + size = device_property_count_u32(dev, "gpio-reserved-ranges"); + if (size > 0 && size % 2 == 0) + return size; - mutex_unlock(&sysfs_lock); - return status; + return 0; } -static ssize_t gpio_edge_store(struct device *dev, - struct device_attribute *attr, const char *buf, size_t size) +static int gpiochip_apply_reserved_ranges(struct gpio_chip *gc) { - struct gpio_desc *desc = dev_get_drvdata(dev); - ssize_t status; - int i; + struct device *dev = &gc->gpiodev->dev; + unsigned int size; + u32 *ranges; + int ret; - for (i = 0; i < ARRAY_SIZE(trigger_types); i++) - if (sysfs_streq(trigger_types[i].name, buf)) - goto found; - return -EINVAL; + size = gpiochip_count_reserved_ranges(gc); + if (size == 0) + return 0; -found: - mutex_lock(&sysfs_lock); + ranges = kmalloc_array(size, sizeof(*ranges), GFP_KERNEL); + if (!ranges) + return -ENOMEM; - if (!test_bit(FLAG_EXPORT, &desc->flags)) - status = -EIO; - else { - status = gpio_setup_irq(desc, dev, trigger_types[i].flags); - if (!status) - status = size; + ret = device_property_read_u32_array(dev, "gpio-reserved-ranges", + ranges, size); + if (ret) { + kfree(ranges); + return ret; } - mutex_unlock(&sysfs_lock); + while (size) { + u32 count = ranges[--size]; + u32 start = ranges[--size]; - return status; -} + if (start >= gc->ngpio || start + count > gc->ngpio) + continue; -static DEVICE_ATTR(edge, 0644, gpio_edge_show, gpio_edge_store); + bitmap_clear(gc->gpiodev->valid_mask, start, count); + } -static int sysfs_set_active_low(struct gpio_desc *desc, struct device *dev, - int value) + kfree(ranges); + return 0; +} + +static int gpiochip_init_valid_mask(struct gpio_chip *gc) { - int status = 0; + int ret; - if (!!test_bit(FLAG_ACTIVE_LOW, &desc->flags) == !!value) + if (!(gpiochip_count_reserved_ranges(gc) || gc->init_valid_mask)) return 0; - if (value) - set_bit(FLAG_ACTIVE_LOW, &desc->flags); - else - clear_bit(FLAG_ACTIVE_LOW, &desc->flags); + gc->gpiodev->valid_mask = gpiochip_allocate_mask(gc); + if (!gc->gpiodev->valid_mask) + return -ENOMEM; - /* reconfigure poll(2) support if enabled on one edge only */ - if (dev != NULL && (!!test_bit(FLAG_TRIG_RISE, &desc->flags) ^ - !!test_bit(FLAG_TRIG_FALL, &desc->flags))) { - unsigned long trigger_flags = desc->flags & GPIO_TRIGGER_MASK; + ret = gpiochip_apply_reserved_ranges(gc); + if (ret) + return ret; - gpio_setup_irq(desc, dev, 0); - status = gpio_setup_irq(desc, dev, trigger_flags); - } + if (gc->init_valid_mask) + return gc->init_valid_mask(gc, + gc->gpiodev->valid_mask, + gc->ngpio); - return status; + return 0; } -static ssize_t gpio_active_low_show(struct device *dev, - struct device_attribute *attr, char *buf) +static void gpiochip_free_valid_mask(struct gpio_chip *gc) { - const struct gpio_desc *desc = dev_get_drvdata(dev); - ssize_t status; + gpiochip_free_mask(&gc->gpiodev->valid_mask); +} - mutex_lock(&sysfs_lock); +static int gpiochip_add_pin_ranges(struct gpio_chip *gc) +{ + /* + * 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 (device_property_present(&gc->gpiodev->dev, "gpio-ranges")) + return 0; - if (!test_bit(FLAG_EXPORT, &desc->flags)) - status = -EIO; - else - status = sprintf(buf, "%d\n", - !!test_bit(FLAG_ACTIVE_LOW, &desc->flags)); + if (gc->add_pin_ranges) + return gc->add_pin_ranges(gc); - mutex_unlock(&sysfs_lock); + return 0; +} - return status; +/** + * 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) +{ + return gc->gpiodev->valid_mask; } +EXPORT_SYMBOL_GPL(gpiochip_query_valid_mask); -static ssize_t gpio_active_low_store(struct device *dev, - struct device_attribute *attr, const char *buf, size_t size) +bool gpiochip_line_is_valid(const struct gpio_chip *gc, + unsigned int offset) { - struct gpio_desc *desc = dev_get_drvdata(dev); - ssize_t status; + /* + * hog pins are requested before registering GPIO chip + */ + if (!gc->gpiodev) + return true; - mutex_lock(&sysfs_lock); + /* 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); - if (!test_bit(FLAG_EXPORT, &desc->flags)) { - status = -EIO; - } else { - long value; +static void gpiod_free_irqs(struct gpio_desc *desc) +{ + int irq = gpiod_to_irq(desc); + struct irq_desc *irqd = irq_to_desc(irq); + void *cookie; + + for (;;) { + /* + * 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(). + */ + scoped_guard(mutex, &irqd->request_mutex) { + if (!irq_desc_has_action(irqd)) + return; + + cookie = irqd->action->dev_id; + } - status = strict_strtol(buf, 0, &value); - if (status == 0) - status = sysfs_set_active_low(desc, dev, value != 0); + free_irq(irq, cookie); } +} - mutex_unlock(&sysfs_lock); +/* + * 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 void gpiochip_free_remaining_irqs(struct gpio_chip *gc) +{ + struct gpio_desc *desc; - return status ? : size; + for_each_gpio_desc_with_flag(gc, desc, GPIOD_FLAG_USED_AS_IRQ) + gpiod_free_irqs(desc); } -static const DEVICE_ATTR(active_low, 0644, - gpio_active_low_show, gpio_active_low_store); +static void gpiodev_release(struct device *dev) +{ + struct gpio_device *gdev = to_gpio_device(dev); -static const struct attribute *gpio_attrs[] = { - &dev_attr_value.attr, - &dev_attr_active_low.attr, - NULL, -}; + /* Call pending kfree()s for descriptor labels. */ + synchronize_srcu(&gdev->desc_srcu); + cleanup_srcu_struct(&gdev->desc_srcu); -static const struct attribute_group gpio_attr_group = { - .attrs = (struct attribute **) gpio_attrs, + 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 /* - * /sys/class/gpio/gpiochipN/ - * /base ... matching gpio_chip.base (N) - * /label ... matching gpio_chip.label - * /ngpio ... matching gpio_chip.ngpio + * 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 ssize_t chip_base_show(struct device *dev, - struct device_attribute *attr, char *buf) +static int gpiochip_setup_dev(struct gpio_device *gdev) { - const struct gpio_chip *chip = dev_get_drvdata(dev); + struct fwnode_handle *fwnode = dev_fwnode(&gdev->dev); + int ret; + + device_initialize(&gdev->dev); - return sprintf(buf, "%d\n", chip->base); + /* + * 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); + + ret = gcdev_register(gdev, gpio_devt); + if (ret) + return ret; + + ret = gpiochip_sysfs_register(gdev); + if (ret) + goto err_remove_device; + + 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: + gcdev_unregister(gdev); + return ret; } -static DEVICE_ATTR(base, 0444, chip_base_show, NULL); -static ssize_t chip_label_show(struct device *dev, - struct device_attribute *attr, char *buf) +static void gpiochip_machine_hog(struct gpio_chip *gc, struct gpiod_hog *hog) { - const struct gpio_chip *chip = dev_get_drvdata(dev); + struct gpio_desc *desc; + int rv; + + desc = gpiochip_get_desc(gc, hog->chip_hwnum); + if (IS_ERR(desc)) { + gpiochip_err(gc, "%s: unable to get GPIO desc: %ld\n", + __func__, PTR_ERR(desc)); + return; + } - return sprintf(buf, "%s\n", chip->label ? : ""); + rv = gpiod_hog(desc, hog->line_name, hog->lflags, hog->dflags); + if (rv) + gpiod_err(desc, "%s: unable to hog GPIO line (%s:%u): %d\n", + __func__, gc->label, hog->chip_hwnum, rv); } -static DEVICE_ATTR(label, 0444, chip_label_show, NULL); -static ssize_t chip_ngpio_show(struct device *dev, - struct device_attribute *attr, char *buf) +static void machine_gpiochip_add(struct gpio_chip *gc) { - const struct gpio_chip *chip = dev_get_drvdata(dev); + struct gpiod_hog *hog; + + guard(mutex)(&gpio_machine_hogs_mutex); - return sprintf(buf, "%u\n", chip->ngpio); + list_for_each_entry(hog, &gpio_machine_hogs, list) { + if (!strcmp(gc->label, hog->chip_label)) + gpiochip_machine_hog(gc, hog); + } } -static DEVICE_ATTR(ngpio, 0444, chip_ngpio_show, NULL); -static const struct attribute *gpiochip_attrs[] = { - &dev_attr_base.attr, - &dev_attr_label.attr, - &dev_attr_ngpio.attr, - NULL, -}; +static void gpiochip_setup_devs(void) +{ + struct gpio_device *gdev; + int ret; -static const struct attribute_group gpiochip_attr_group = { - .attrs = (struct attribute **) gpiochip_attrs, -}; + guard(srcu)(&gpio_devices_srcu); -/* - * /sys/class/gpio/export ... write-only - * integer N ... number of GPIO to export (full access) - * /sys/class/gpio/unexport ... write-only - * integer N ... number of GPIO to unexport - */ -static ssize_t export_store(struct class *class, - struct class_attribute *attr, - const char *buf, size_t len) -{ - long gpio; - struct gpio_desc *desc; - int status; - - status = strict_strtol(buf, 0, &gpio); - if (status < 0) - goto done; - - desc = gpio_to_desc(gpio); - /* reject invalid GPIOs */ - if (!desc) { - pr_warn("%s: invalid GPIO %ld\n", __func__, gpio); - return -EINVAL; + 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); } +} - /* No extra locking here; FLAG_SYSFS just signifies that the - * request and export were done by on behalf of userspace, so - * they may be undone on its behalf too. - */ +static void gpiochip_set_data(struct gpio_chip *gc, void *data) +{ + gc->gpiodev->data = data; +} - status = gpiod_request(desc, "sysfs"); - if (status < 0) { - if (status == -EPROBE_DEFER) - status = -ENODEV; - goto done; - } - status = gpiod_export(desc, true); - if (status < 0) - gpiod_free(desc); - else - set_bit(FLAG_SYSFS, &desc->flags); +/** + * 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); -done: - if (status) - pr_debug("%s: status %d\n", __func__, status); - return status ? : len; + return NULL; } -static ssize_t unexport_store(struct class *class, - struct class_attribute *attr, - const char *buf, size_t len) +int gpiochip_get_ngpios(struct gpio_chip *gc, struct device *dev) { - long gpio; - struct gpio_desc *desc; - int status; + 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; - status = strict_strtol(buf, 0, &gpio); - if (status < 0) - goto done; + gc->ngpio = ngpios; + } - desc = gpio_to_desc(gpio); - /* reject bogus commands (gpio_unexport ignores them) */ - if (!desc) { - pr_warn("%s: invalid GPIO %ld\n", __func__, gpio); + if (gc->ngpio == 0) { + dev_err(dev, "tried to insert a GPIO chip with zero lines\n"); return -EINVAL; } - status = -EINVAL; + if (gc->ngpio > FASTPATH_NGPIO) + dev_warn(dev, "line cnt %u is greater than fast path cnt %u\n", + gc->ngpio, FASTPATH_NGPIO); - /* No extra locking here; FLAG_SYSFS just signifies that the - * request and export were done by on behalf of userspace, so - * they may be undone on its behalf too. - */ - if (test_and_clear_bit(FLAG_SYSFS, &desc->flags)) { - status = 0; - gpiod_free(desc); - } -done: - if (status) - pr_debug("%s: status %d\n", __func__, status); - return status ? : len; + return 0; } +EXPORT_SYMBOL_GPL(gpiochip_get_ngpios); -static struct class_attribute gpio_class_attrs[] = { - __ATTR(export, 0200, NULL, export_store), - __ATTR(unexport, 0200, NULL, unexport_store), - __ATTR_NULL, -}; +int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data, + struct lock_class_key *lock_key, + struct lock_class_key *request_key) +{ + struct gpio_device *gdev; + unsigned int desc_index; + int base = 0; + int ret; -static struct class gpio_class = { - .name = "gpio", - .owner = THIS_MODULE, + /* + * First: allocate and populate the internal stat container, and + * set up the struct device. + */ + gdev = kzalloc(sizeof(*gdev), GFP_KERNEL); + if (!gdev) + return -ENOMEM; - .class_attrs = gpio_class_attrs, -}; + gdev->dev.type = &gpio_dev_type; + gdev->dev.bus = &gpio_bus_type; + gdev->dev.parent = gc->parent; + rcu_assign_pointer(gdev->chip, gc); + gc->gpiodev = gdev; + gpiochip_set_data(gc, data); -/** - * gpio_export - export a GPIO through sysfs - * @gpio: gpio to make available, already requested - * @direction_may_change: true if userspace may change gpio direction - * Context: arch_initcall or later - * - * When drivers want to make a GPIO accessible to userspace after they - * have requested it -- perhaps while debugging, or as part of their - * public interface -- they may use this routine. If the GPIO can - * change direction (some can't) and the caller allows it, userspace - * will see "direction" sysfs attribute which may be used to change - * the gpio's direction. A "value" attribute will always be provided. - * - * Returns zero on success, else an error. - */ -static int gpiod_export(struct gpio_desc *desc, bool direction_may_change) -{ - unsigned long flags; - int status; - const char *ioname = NULL; - struct device *dev; - int offset; + device_set_node(&gdev->dev, gpiochip_choose_fwnode(gc)); - /* can't export until sysfs is available ... */ - if (!gpio_class.p) { - pr_debug("%s: called too early!\n", __func__); - return -ENOENT; + ret = ida_alloc(&gpio_ida, GFP_KERNEL); + if (ret < 0) + goto err_free_gdev; + 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 = gc->owner; + else + gdev->owner = THIS_MODULE; + + 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) { + ret = -ENOMEM; + goto err_free_dev_name; } - if (!desc) { - pr_debug("%s: invalid gpio descriptor\n", __func__); - return -EINVAL; + gdev->label = kstrdup_const(gc->label ?: "unknown", GFP_KERNEL); + if (!gdev->label) { + ret = -ENOMEM; + goto err_free_descs; } - mutex_lock(&sysfs_lock); + gdev->ngpio = gc->ngpio; + gdev->can_sleep = gc->can_sleep; + + 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; + } + + /* + * 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"); + } + + gdev->base = base; - spin_lock_irqsave(&gpio_lock, flags); - if (!test_bit(FLAG_REQUESTED, &desc->flags) || - test_bit(FLAG_EXPORT, &desc->flags)) { - spin_unlock_irqrestore(&gpio_lock, flags); - pr_debug("%s: gpio %d unavailable (requested=%d, exported=%d)\n", - __func__, desc_to_gpio(desc), - test_bit(FLAG_REQUESTED, &desc->flags), - test_bit(FLAG_EXPORT, &desc->flags)); - status = -EPERM; - goto fail_unlock; + ret = gpiodev_add_to_list_unlocked(gdev); + if (ret) { + gpiochip_err(gc, "GPIO integer space overlap, cannot add chip\n"); + goto err_free_label; + } } - if (!desc->chip->direction_input || !desc->chip->direction_output) - direction_may_change = false; - spin_unlock_irqrestore(&gpio_lock, flags); + rwlock_init(&gdev->line_state_lock); + RAW_INIT_NOTIFIER_HEAD(&gdev->line_state_notifier); + BLOCKING_INIT_NOTIFIER_HEAD(&gdev->device_notifier); - offset = gpio_chip_hwgpio(desc); - if (desc->chip->names && desc->chip->names[offset]) - ioname = desc->chip->names[offset]; + ret = init_srcu_struct(&gdev->srcu); + if (ret) + goto err_remove_from_list; - dev = device_create(&gpio_class, desc->chip->dev, MKDEV(0, 0), - desc, ioname ? ioname : "gpio%u", - desc_to_gpio(desc)); - if (IS_ERR(dev)) { - status = PTR_ERR(dev); - goto fail_unlock; - } + ret = init_srcu_struct(&gdev->desc_srcu); + if (ret) + goto err_cleanup_gdev_srcu; + +#ifdef CONFIG_PINCTRL + INIT_LIST_HEAD(&gdev->pin_ranges); +#endif + + if (gc->names) + gpiochip_set_desc_names(gc); + + ret = gpiochip_set_names(gc); + if (ret) + goto err_cleanup_desc_srcu; + + ret = gpiochip_init_valid_mask(gc); + if (ret) + goto err_cleanup_desc_srcu; - status = sysfs_create_group(&dev->kobj, &gpio_attr_group); - if (status) - goto fail_unregister_device; + for (desc_index = 0; desc_index < gc->ngpio; desc_index++) { + struct gpio_desc *desc = &gdev->descs[desc_index]; - if (direction_may_change) { - status = device_create_file(dev, &dev_attr_direction); - if (status) - goto fail_unregister_device; + desc->gdev = gdev; + + /* + * 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 + assign_bit(GPIOD_FLAG_IS_OUT, + &desc->flags, !gc->direction_input); } - if (gpiod_to_irq(desc) >= 0 && (direction_may_change || - !test_bit(FLAG_IS_OUT, &desc->flags))) { - status = device_create_file(dev, &dev_attr_edge); - if (status) - goto fail_unregister_device; + 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(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, + * we get a device node entry in sysfs under + * /sys/bus/gpio/devices/gpiochipN/dev that can be used for + * coldplug of device nodes and other udev business. + * We can do this only if gpiolib has been initialized. + * Otherwise, defer until later. + */ + if (gpiolib_initialized) { + ret = gpiochip_setup_dev(gdev); + if (ret) + goto err_teardown_shared; } - set_bit(FLAG_EXPORT, &desc->flags); - mutex_unlock(&sysfs_lock); return 0; -fail_unregister_device: - device_unregister(dev); -fail_unlock: - mutex_unlock(&sysfs_lock); - pr_debug("%s: gpio%d status %d\n", __func__, desc_to_gpio(desc), - status); - return status; +err_teardown_shared: + gpio_device_teardown_shared(gdev); +err_remove_irqchip: + gpiochip_irqchip_remove(gc); +err_remove_irqchip_mask: + 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: + 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_free(&gpio_ida, gdev->id); +err_free_gdev: + kfree(gdev); +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); -int gpio_export(unsigned gpio, bool direction_may_change) +/** + * gpiochip_remove() - unregister a gpio_chip + * @gc: the chip to unregister + * + * A gpio_chip with any GPIOs still requested may not be removed. + */ +void gpiochip_remove(struct gpio_chip *gc) { - return gpiod_export(gpio_to_desc(gpio), direction_may_change); -} -EXPORT_SYMBOL_GPL(gpio_export); + struct gpio_device *gdev = gc->gpiodev; + + /* FIXME: should the legacy sysfs handling be moved to gpio_device? */ + gpiochip_sysfs_unregister(gdev); + 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 */ + 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. + */ + gpiochip_set_data(gc, NULL); -static int match_export(struct device *dev, const void *data) -{ - return dev_get_drvdata(dev) == data; + /* + * The gpiochip side puts its use of the device to rest here: + * if there are no userspace clients, the chardev and device will + * be removed, else it will be dangling until the last user is + * gone. + */ + gcdev_unregister(gdev); + gpio_device_put(gdev); } +EXPORT_SYMBOL_GPL(gpiochip_remove); /** - * gpio_export_link - create a sysfs link to an exported GPIO node - * @dev: device under which to create symlink - * @name: name of the symlink - * @gpio: gpio to create symlink to, already exported + * gpio_device_find() - find a specific GPIO device + * @data: data to pass to match function + * @match: Callback function to check gpio_chip + * + * Returns: + * New reference to struct gpio_device. * - * Set up a symlink from /sys/.../dev/name to /sys/class/gpio/gpioN - * node. Caller is responsible for unlinking. + * 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 zero on success, else an error. + * 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(). */ -static int gpiod_export_link(struct device *dev, const char *name, - struct gpio_desc *desc) +struct gpio_device *gpio_device_find(const void *data, + int (*match)(struct gpio_chip *gc, + const void *data)) { - int status = -EINVAL; + struct gpio_device *gdev; + struct gpio_chip *gc; - if (!desc) { - pr_warn("%s: invalid GPIO\n", __func__); - return -EINVAL; - } + might_sleep(); - mutex_lock(&sysfs_lock); + guard(srcu)(&gpio_devices_srcu); - if (test_bit(FLAG_EXPORT, &desc->flags)) { - struct device *tdev; + list_for_each_entry_srcu(gdev, &gpio_devices, list, + srcu_read_lock_held(&gpio_devices_srcu)) { + if (!device_is_registered(&gdev->dev)) + continue; - tdev = class_find_device(&gpio_class, NULL, desc, match_export); - if (tdev != NULL) { - status = sysfs_create_link(&dev->kobj, &tdev->kobj, - name); - } else { - status = -ENODEV; - } + guard(srcu)(&gdev->srcu); + + gc = srcu_dereference(gdev->chip, &gdev->srcu); + + if (gc && match(gc, data)) + return gpio_device_get(gdev); } - mutex_unlock(&sysfs_lock); + return NULL; +} +EXPORT_SYMBOL_GPL(gpio_device_find); + +static int gpio_chip_match_by_label(struct gpio_chip *gc, const void *label) +{ + return gc->label && !strcmp(gc->label, label); +} + +/** + * gpio_device_find_by_label() - wrapper around gpio_device_find() finding the + * GPIO device by its backing chip's label + * @label: Label 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_label(const char *label) +{ + return gpio_device_find((void *)label, gpio_chip_match_by_label); +} +EXPORT_SYMBOL_GPL(gpio_device_find_by_label); + +static int gpio_chip_match_by_fwnode(struct gpio_chip *gc, const void *fwnode) +{ + return device_match_fwnode(&gc->gpiodev->dev, fwnode); +} - if (status) - pr_debug("%s: gpio%d status %d\n", __func__, desc_to_gpio(desc), - status); +/** + * 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(gpio_device_find_by_fwnode); - return status; +/** + * 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) +{ + return to_gpio_device(get_device(&gdev->dev)); } +EXPORT_SYMBOL_GPL(gpio_device_get); -int gpio_export_link(struct device *dev, const char *name, unsigned gpio) +/** + * 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) { - return gpiod_export_link(dev, name, gpio_to_desc(gpio)); + put_device(&gdev->dev); } -EXPORT_SYMBOL_GPL(gpio_export_link); +EXPORT_SYMBOL_GPL(gpio_device_put); /** - * gpio_sysfs_set_active_low - set the polarity of gpio sysfs value - * @gpio: gpio to change - * @value: non-zero to use active low, i.e. inverted values + * gpio_device_to_device() - Retrieve the address of the underlying struct + * device. + * @gdev: GPIO device for which to return the address. * - * Set the polarity of /sys/class/gpio/gpioN/value sysfs attribute. - * The GPIO does not have to be exported yet. If poll(2) support has - * been enabled for either rising or falling edge, it will be - * reconfigured to follow the new polarity. + * This does not increase the reference count of the GPIO device nor the + * underlying struct device. * - * Returns zero on success, else an error. + * Returns: + * Address of struct device backing this GPIO device. */ -static int gpiod_sysfs_set_active_low(struct gpio_desc *desc, int value) +struct device *gpio_device_to_device(struct gpio_device *gdev) { - struct device *dev = NULL; - int status = -EINVAL; + return &gdev->dev; +} +EXPORT_SYMBOL_GPL(gpio_device_to_device); - if (!desc) { - pr_warn("%s: invalid GPIO\n", __func__); - return -EINVAL; - } +#ifdef CONFIG_GPIOLIB_IRQCHIP - mutex_lock(&sysfs_lock); +/* + * The following is irqchip helper code for gpiochips. + */ - if (test_bit(FLAG_EXPORT, &desc->flags)) { - dev = class_find_device(&gpio_class, NULL, desc, match_export); - if (dev == NULL) { - status = -ENODEV; - goto unlock; - } - } +static int gpiochip_irqchip_init_hw(struct gpio_chip *gc) +{ + struct gpio_irq_chip *girq = &gc->irq; + + if (!girq->init_hw) + return 0; + + return girq->init_hw(gc); +} - status = sysfs_set_active_low(desc, dev, value); +static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gc) +{ + struct gpio_irq_chip *girq = &gc->irq; -unlock: - mutex_unlock(&sysfs_lock); + if (!girq->init_valid_mask) + return 0; + + girq->valid_mask = gpiochip_allocate_mask(gc); + if (!girq->valid_mask) + return -ENOMEM; - if (status) - pr_debug("%s: gpio%d status %d\n", __func__, desc_to_gpio(desc), - status); + girq->init_valid_mask(gc, girq->valid_mask, gc->ngpio); - return status; + return 0; +} + +static void gpiochip_irqchip_free_valid_mask(struct gpio_chip *gc) +{ + gpiochip_free_mask(&gc->irq.valid_mask); } -int gpio_sysfs_set_active_low(unsigned gpio, int value) +static bool gpiochip_irqchip_irq_valid(const struct gpio_chip *gc, + unsigned int offset) { - return gpiod_sysfs_set_active_low(gpio_to_desc(gpio), value); + if (!gpiochip_line_is_valid(gc, offset)) + return false; + /* No mask means all valid */ + if (likely(!gc->irq.valid_mask)) + return true; + return test_bit(offset, gc->irq.valid_mask); } -EXPORT_SYMBOL_GPL(gpio_sysfs_set_active_low); + +#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY /** - * gpio_unexport - reverse effect of gpio_export() - * @gpio: gpio to make unavailable - * - * This is implicit on gpio_free(). + * 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 gpiod_unexport(struct gpio_desc *desc) +static void gpiochip_set_hierarchical_irqchip(struct gpio_chip *gc, + struct irq_chip *irqchip) { - int status = 0; - struct device *dev = NULL; - - if (!desc) { - pr_warn("%s: invalid GPIO\n", __func__); + /* DT will deal with mapping each IRQ as we go along */ + if (is_of_node(gc->irq.fwnode)) 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); + } + } } - mutex_lock(&sysfs_lock); + gpiochip_err(gc, "%s unknown fwnode type proceed anyway\n", __func__); - if (test_bit(FLAG_EXPORT, &desc->flags)) { + return; +} - dev = class_find_device(&gpio_class, NULL, desc, match_export); - if (dev) { - gpio_setup_irq(desc, dev, 0); - clear_bit(FLAG_EXPORT, &desc->flags); - } else - status = -ENODEV; +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; +} - mutex_unlock(&sysfs_lock); +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; - if (dev) { - device_unregister(dev); - put_device(dev); + /* + * The nr_irqs parameter is always one except for PCI multi-MSI + * so this should not happen. + */ + WARN_ON(nr_irqs != 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; - if (status) - pr_debug("%s: gpio%d status %d\n", __func__, desc_to_gpio(desc), - status); + 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; } -void gpio_unexport(unsigned gpio) +static unsigned int gpiochip_child_offset_to_irq_noop(struct gpio_chip *gc, + unsigned int offset) { - gpiod_unexport(gpio_to_desc(gpio)); + return offset; } -EXPORT_SYMBOL_GPL(gpio_unexport); -static int gpiochip_export(struct gpio_chip *chip) +/** + * 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. + */ +static int gpiochip_irq_domain_activate(struct irq_domain *domain, + struct irq_data *data, bool reserve) { - int status; - struct device *dev; + struct gpio_chip *gc = domain->host_data; + unsigned int hwirq = irqd_to_hwirq(data); - /* Many systems register gpio chips for SOC support very early, - * before driver model support is available. In those cases we - * export this later, in gpiolib_sysfs_init() ... here we just - * verify that _some_ field of gpio_class got initialized. - */ - if (!gpio_class.p) - return 0; + return gpiochip_lock_as_irq(gc, hwirq); +} - /* use chip->base for the ID; it's already known to be unique */ - mutex_lock(&sysfs_lock); - dev = device_create(&gpio_class, chip->dev, MKDEV(0, 0), chip, - "gpiochip%d", chip->base); - if (!IS_ERR(dev)) { - status = sysfs_create_group(&dev->kobj, - &gpiochip_attr_group); - } else - status = PTR_ERR(dev); - chip->exported = (status == 0); - mutex_unlock(&sysfs_lock); +/** + * 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. + */ +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); - if (status) { - unsigned long flags; - unsigned gpio; + 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; +} - spin_lock_irqsave(&gpio_lock, flags); - gpio = 0; - while (gpio < chip->ngpio) - chip->desc[gpio++].chip = NULL; - spin_unlock_irqrestore(&gpio_lock, flags); +static struct irq_domain *gpiochip_hierarchy_create_domain(struct gpio_chip *gc) +{ + struct irq_domain *domain; - pr_debug("%s: chip %s status %d\n", __func__, - chip->label, status); + if (!gc->irq.child_to_parent_hwirq || + !gc->irq.fwnode) { + gpiochip_err(gc, "missing irqdomain vital data\n"); + return ERR_PTR(-EINVAL); } - return status; + 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; } -static void gpiochip_unexport(struct gpio_chip *chip) +int gpiochip_populate_parent_fwspec_twocell(struct gpio_chip *gc, + union gpio_irq_fwspec *gfwspec, + unsigned int parent_hwirq, + unsigned int parent_type) { - int status; - struct device *dev; + struct irq_fwspec *fwspec = &gfwspec->fwspec; - mutex_lock(&sysfs_lock); - dev = class_find_device(&gpio_class, NULL, chip, match_export); - if (dev) { - put_device(dev); - device_unregister(dev); - chip->exported = 0; - status = 0; - } else - status = -ENODEV; - mutex_unlock(&sysfs_lock); + fwspec->fwnode = gc->irq.parent_domain->fwnode; + fwspec->param_count = 2; + fwspec->param[0] = parent_hwirq; + fwspec->param[1] = parent_type; - if (status) - pr_debug("%s: chip %s status %d\n", __func__, - chip->label, status); + return 0; } +EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_twocell); -static int __init gpiolib_sysfs_init(void) +int gpiochip_populate_parent_fwspec_fourcell(struct gpio_chip *gc, + union gpio_irq_fwspec *gfwspec, + unsigned int parent_hwirq, + unsigned int parent_type) { - int status; - unsigned long flags; - struct gpio_chip *chip; + struct irq_fwspec *fwspec = &gfwspec->fwspec; - status = class_register(&gpio_class); - if (status < 0) - return status; + 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; - /* Scan and register the gpio_chips which registered very - * early (e.g. before the class_register above was called). - * - * We run before arch_initcall() so chip->dev nodes can have - * registered, and so arch_initcall() can always gpio_export(). - */ - spin_lock_irqsave(&gpio_lock, flags); - list_for_each_entry(chip, &gpio_chips, list) { - if (!chip || chip->exported) - continue; + return 0; +} +EXPORT_SYMBOL_GPL(gpiochip_populate_parent_fwspec_fourcell); - spin_unlock_irqrestore(&gpio_lock, flags); - status = gpiochip_export(chip); - spin_lock_irqsave(&gpio_lock, flags); - } - spin_unlock_irqrestore(&gpio_lock, flags); +#else +static struct irq_domain *gpiochip_hierarchy_create_domain(struct gpio_chip *gc) +{ + return ERR_PTR(-EINVAL); +} - return status; +static bool gpiochip_hierarchy_is_hierarchical(struct gpio_chip *gc) +{ + return false; } -postcore_initcall(gpiolib_sysfs_init); -#else -static inline int gpiochip_export(struct gpio_chip *chip) +#endif /* CONFIG_IRQ_DOMAIN_HIERARCHY */ + +/** + * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip + * @d: the irqdomain used by this irqchip + * @irq: the global irq number used by this GPIO irqchip irq + * @hwirq: the local IRQ/GPIO line offset on this gpiochip + * + * 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. + */ +static int gpiochip_irq_map(struct irq_domain *d, unsigned int irq, + irq_hw_number_t hwirq) { + struct gpio_chip *gc = d->host_data; + int ret = 0; + + if (!gpiochip_irqchip_irq_valid(gc, hwirq)) + return -ENXIO; + + 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, 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 (gc->irq.threaded) + irq_set_nested_thread(irq, 1); + irq_set_noprobe(irq); + + 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 (ret < 0) + return ret; + + /* + * No set-up of the hardware will happen if IRQ_TYPE_NONE + * is passed as default type. + */ + if (gc->irq.default_type != IRQ_TYPE_NONE) + irq_set_irq_type(irq, gc->irq.default_type); + return 0; } -static inline void gpiochip_unexport(struct gpio_chip *chip) +static void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq) +{ + struct gpio_chip *gc = d->host_data; + + if (gc->irq.threaded) + irq_set_nested_thread(irq, 0); + irq_set_chip_and_handler(irq, NULL, NULL); + irq_set_chip_data(irq, NULL); +} + +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 inline int gpiod_export(struct gpio_desc *desc, - bool direction_may_change) +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_twothreecell, +}; + +static struct irq_domain *gpiochip_simple_create_domain(struct gpio_chip *gc) { - return -ENOSYS; + 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 inline int gpiod_export_link(struct device *dev, const char *name, - struct gpio_desc *desc) +static int gpiochip_to_irq(struct gpio_chip *gc, unsigned int offset) { - return -ENOSYS; + 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; + +#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); } -static inline int gpiod_sysfs_set_active_low(struct gpio_desc *desc, int value) +int gpiochip_irq_reqres(struct irq_data *d) { - return -ENOSYS; + 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 inline void gpiod_unexport(struct gpio_desc *desc) +void gpiochip_irq_relres(struct irq_data *d) { + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + unsigned int hwirq = irqd_to_hwirq(d); + + gpiochip_relres_irq(gc, hwirq); } +EXPORT_SYMBOL(gpiochip_irq_relres); -#endif /* CONFIG_GPIO_SYSFS */ +static void gpiochip_irq_mask(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + unsigned int hwirq = irqd_to_hwirq(d); -/* - * Add a new chip to the global chips list, keeping the list of chips sorted - * by base order. - * - * Return -EBUSY if the new chip overlaps with some other chip's integer - * space. - */ -static int gpiochip_add_to_list(struct gpio_chip *chip) + 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 list_head *pos = &gpio_chips; - struct gpio_chip *_chip; - int err = 0; + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + unsigned int hwirq = irqd_to_hwirq(d); - /* find where to insert our chip */ - list_for_each(pos, &gpio_chips) { - _chip = list_entry(pos, struct gpio_chip, list); - /* shall we insert before _chip? */ - if (_chip->base >= chip->base + chip->ngpio) - break; + 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 *gc = irq_data_get_irq_chip_data(d); + unsigned int hwirq = irqd_to_hwirq(d); + + gpiochip_enable_irq(gc, hwirq); + gc->irq.irq_enable(d); +} + +static void gpiochip_irq_disable(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + unsigned int hwirq = irqd_to_hwirq(d); + + gc->irq.irq_disable(d); + gpiochip_disable_irq(gc, hwirq); +} + +static void gpiochip_set_irq_hooks(struct gpio_chip *gc) +{ + 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(gc->irq.irq_enable)) + return; + /* Check if the irqchip already has this hook... */ + 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. + */ + gpiochip_info(gc, + "detected irqchip that is shared with multiple gpiochips: please fix the driver.\n"); + return; } - /* are we stepping on the chip right before? */ - if (pos != &gpio_chips && pos->prev != &gpio_chips) { - _chip = list_entry(pos->prev, struct gpio_chip, list); - if (_chip->base + _chip->ngpio > chip->base) { - dev_err(chip->dev, - "GPIO integer space overlap, cannot add chip\n"); - err = -EBUSY; - } + 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 (!err) - list_add_tail(&chip->list, pos); + 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; - return err; + 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() - register a gpio_chip - * @chip: the chip to register, with chip->base initialized - * Context: potentially before irqs or kmalloc will work + * gpiochip_add_irqchip() - adds an IRQ chip to a GPIO chip + * @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 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. - * - * When gpiochip_add() is called very early during boot, so that GPIOs - * can be freely used, the chip->dev device must be registered before - * the gpio framework's arch_initcall(). Otherwise sysfs initialization - * for GPIOs will fail rudely. - * - * If chip->base is negative, this requests dynamic assignment of - * a range of valid GPIOs. + * Returns: + * 0 on success, or a negative errno on failure. */ -int gpiochip_add(struct gpio_chip *chip) +static int gpiochip_add_irqchip(struct gpio_chip *gc, + struct lock_class_key *lock_key, + struct lock_class_key *request_key) { - unsigned long flags; - int status = 0; - unsigned id; - int base = chip->base; - - if ((!gpio_is_valid(base) || !gpio_is_valid(base + chip->ngpio - 1)) - && base >= 0) { - status = -EINVAL; - goto fail; - } + 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; - spin_lock_irqsave(&gpio_lock, flags); + if (!irqchip) + return 0; - if (base < 0) { - base = gpiochip_find_base(chip->ngpio); - if (base < 0) { - status = base; - goto unlock; - } - chip->base = base; + 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; } - status = gpiochip_add_to_list(chip); + type = gc->irq.default_type; - if (status == 0) { - chip->desc = &gpio_desc[chip->base]; + /* + * 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(fwnode && type != IRQ_TYPE_NONE, + "%pfw: Ignoring %u default trigger\n", fwnode, type)) + type = IRQ_TYPE_NONE; - for (id = 0; id < chip->ngpio; id++) { - struct gpio_desc *desc = &chip->desc[id]; - desc->chip = chip; + gc->irq.default_type = type; + gc->irq.lock_key = lock_key; + gc->irq.request_key = request_key; - /* REVISIT: most hardware initializes GPIOs as - * inputs (often with pullups enabled) so power - * usage is minimized. Linux code should set the - * gpio direction first thing; but until it does, - * and in case chip->get_direction is not set, - * we may expose the wrong direction in sysfs. + /* 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); + + if (gc->irq.parent_handler) { + for (i = 0; i < gc->irq.num_parents; i++) { + void *data; + + if (gc->irq.per_parent_data) + data = gc->irq.parent_handler_data_array[i]; + else + data = gc->irq.parent_handler_data ?: gc; + + /* + * The parent IRQ chip is already using the chip_data + * for this IRQ chip, so our callbacks simply use the + * handler_data. */ - desc->flags = !chip->direction_input - ? (1 << FLAG_IS_OUT) - : 0; + irq_set_chained_handler_and_data(gc->irq.parents[i], + gc->irq.parent_handler, + data); } } - spin_unlock_irqrestore(&gpio_lock, flags); + gpiochip_set_irq_hooks(gc); -#ifdef CONFIG_PINCTRL - INIT_LIST_HEAD(&chip->pin_ranges); -#endif - - of_gpiochip_add(chip); - - if (status) - goto fail; - - status = gpiochip_export(chip); - if (status) - goto fail; + ret = gpiochip_irqchip_add_allocated_domain(gc, domain, false); + if (ret) + return ret; - pr_debug("gpiochip_add: registered GPIOs %d to %d on device: %s\n", - chip->base, chip->base + chip->ngpio - 1, - chip->label ? : "generic"); + acpi_gpiochip_request_interrupts(gc); return 0; - -unlock: - spin_unlock_irqrestore(&gpio_lock, flags); -fail: - /* failures here can mean systems won't boot... */ - pr_err("gpiochip_add: gpios %d..%d (%s) failed to register\n", - chip->base, chip->base + chip->ngpio - 1, - chip->label ? : "generic"); - return status; } -EXPORT_SYMBOL_GPL(gpiochip_add); /** - * gpiochip_remove() - unregister a gpio_chip - * @chip: the chip to unregister + * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip + * @gc: the gpiochip to remove the irqchip from * - * A gpio_chip with any GPIOs still requested may not be removed. + * This is called only from gpiochip_remove() */ -int gpiochip_remove(struct gpio_chip *chip) +static void gpiochip_irqchip_remove(struct gpio_chip *gc) { - unsigned long flags; - int status = 0; - unsigned id; + struct irq_chip *irqchip = gc->irq.chip; + unsigned int offset; - spin_lock_irqsave(&gpio_lock, flags); + acpi_gpiochip_free_interrupts(gc); - gpiochip_remove_pin_ranges(chip); - of_gpiochip_remove(chip); + if (irqchip && gc->irq.parent_handler) { + struct gpio_irq_chip *irq = &gc->irq; + unsigned int i; - for (id = 0; id < chip->ngpio; id++) { - if (test_bit(FLAG_REQUESTED, &chip->desc[id].flags)) { - status = -EBUSY; - break; + for (i = 0; i < irq->num_parents; i++) + irq_set_chained_handler_and_data(irq->parents[i], + NULL, NULL); + } + + /* Remove all IRQ mappings and delete the domain */ + if (!gc->irq.domain_is_allocated_externally && gc->irq.domain) { + unsigned int irq; + + for (offset = 0; offset < gc->ngpio; offset++) { + if (!gpiochip_irqchip_irq_valid(gc, offset)) + continue; + + irq = irq_find_mapping(gc->irq.domain, offset); + irq_dispose_mapping(irq); } + + irq_domain_remove(gc->irq.domain); } - if (status == 0) { - for (id = 0; id < chip->ngpio; id++) - chip->desc[id].chip = NULL; - list_del(&chip->list); + 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 = gc->irq.irq_enable; + irqchip->irq_disable = gc->irq.irq_disable; + } } + gc->irq.irq_enable = NULL; + gc->irq.irq_disable = NULL; + gc->irq.chip = NULL; - spin_unlock_irqrestore(&gpio_lock, flags); + gpiochip_irqchip_free_valid_mask(gc); +} - if (status == 0) - gpiochip_unexport(chip); +/** + * 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. + * + * Returns: + * 0 on success, or negative errno on failure. + */ +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_domain); - return status; +#else /* CONFIG_GPIOLIB_IRQCHIP */ + +static inline int gpiochip_add_irqchip(struct gpio_chip *gc, + struct lock_class_key *lock_key, + struct lock_class_key *request_key) +{ + return 0; } -EXPORT_SYMBOL_GPL(gpiochip_remove); +static void gpiochip_irqchip_remove(struct gpio_chip *gc) {} + +static inline int gpiochip_irqchip_init_hw(struct gpio_chip *gc) +{ + return 0; +} + +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_find() - iterator for locating a specific gpio_chip - * @data: data to pass to match function - * @callback: Callback function to check gpio_chip + * gpiochip_generic_request() - request the gpio function for a pin + * @gc: the gpiochip owning the GPIO + * @offset: the offset of the GPIO to request for GPIO function * - * 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: + * 0 on success, or negative errno on failure. */ -struct gpio_chip *gpiochip_find(void *data, - int (*match)(struct gpio_chip *chip, - void *data)) +int gpiochip_generic_request(struct gpio_chip *gc, unsigned int offset) { - struct gpio_chip *chip; - unsigned long flags; +#ifdef CONFIG_PINCTRL + if (list_empty(&gc->gpiodev->pin_ranges)) + return 0; +#endif - spin_lock_irqsave(&gpio_lock, flags); - list_for_each_entry(chip, &gpio_chips, list) - if (match(chip, data)) - break; + return pinctrl_gpio_request(gc, offset); +} +EXPORT_SYMBOL_GPL(gpiochip_generic_request); - /* No match? */ - if (&chip->list == &gpio_chips) - chip = NULL; - spin_unlock_irqrestore(&gpio_lock, flags); +/** + * gpiochip_generic_free() - free the gpio function from a pin + * @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 *gc, unsigned int offset) +{ +#ifdef CONFIG_PINCTRL + if (list_empty(&gc->gpiodev->pin_ranges)) + return; +#endif - return chip; + pinctrl_gpio_free(gc, offset); } -EXPORT_SYMBOL_GPL(gpiochip_find); +EXPORT_SYMBOL_GPL(gpiochip_generic_free); + +/** + * gpiochip_generic_config() - apply configuration for a pin + * @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 *gc, unsigned int offset, + unsigned long 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); #ifdef CONFIG_PINCTRL /** - * gpiochip_add_pin_range() - add a range for GPIO <-> pin mapping - * @chip: the gpiochip to add the range for - * @pinctrl_name: the dev_name() of the pin controller to map to + * gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping + * @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 + * + * 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 negative errno on failure. + */ +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 = gc->gpiodev; + int ret; + + pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); + if (!pin_range) + return -ENOMEM; + + /* Use local offset as range ID */ + pin_range->range.id = gpio_offset; + pin_range->range.gc = gc; + pin_range->range.name = gc->label; + pin_range->range.base = gdev->base + gpio_offset; + pin_range->pctldev = pctldev; + + ret = pinctrl_get_group_pins(pctldev, pin_group, + &pin_range->range.pins, + &pin_range->range.npins); + if (ret < 0) { + kfree(pin_range); + return ret; + } + + pinctrl_add_gpio_range(pctldev, &pin_range->range); + + 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); + + list_add_tail(&pin_range->node, &gdev->pin_ranges); + + return 0; +} +EXPORT_SYMBOL_GPL(gpiochip_add_pingroup_range); + +/** + * 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 + * + * 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 = gc->gpiodev; int ret; pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL); - if (!pin_range) { - pr_err("%s: GPIO chip: failed to allocate pin ranges\n", - chip->label); + 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.base = chip->base + gpio_offset; + 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); - pr_err("%s: GPIO chip: could not create pin range\n", - chip->label); + gpiochip_err(gc, "could not create pin range\n"); kfree(pin_range); return ret; } - pr_debug("GPIO chip %s: created GPIO range %d->%d ==> %s PIN %d->%d\n", - chip->label, 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, &chip->pin_ranges); + 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 = gc->gpiodev; - list_for_each_entry_safe(pin_range, tmp, &chip->pin_ranges, node) { + list_for_each_entry_safe(pin_range, tmp, &gdev->pin_ranges, node) { list_del(&pin_range->node); pinctrl_remove_gpio_range(pin_range->pctldev, &pin_range->range); @@ -1392,417 +2456,831 @@ EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges); * on each other, and help provide better diagnostics in debugfs. * They're called even less than the "set direction" calls. */ -static int gpiod_request(struct gpio_desc *desc, const char *label) +static int gpiod_request_commit(struct gpio_desc *desc, const char *label) { - struct gpio_chip *chip; - int status = -EPROBE_DEFER; - unsigned long flags; - - if (!desc) { - pr_warn("%s: invalid GPIO\n", __func__); - return -EINVAL; - } + unsigned int offset; + int ret; - spin_lock_irqsave(&gpio_lock, flags); + CLASS(gpio_chip_guard, guard)(desc); + if (!guard.gc) + return -ENODEV; - chip = desc->chip; - if (chip == NULL) - goto done; + if (test_and_set_bit(GPIOD_FLAG_REQUESTED, &desc->flags)) + return -EBUSY; - if (!try_module_get(chip->owner)) - goto done; + 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 { - status = -EBUSY; - module_put(chip->owner); - goto done; - } - - if (chip->request) { - /* chip->request may sleep */ - spin_unlock_irqrestore(&gpio_lock, flags); - status = chip->request(chip, gpio_chip_hwgpio(desc)); - spin_lock_irqsave(&gpio_lock, flags); - - if (status < 0) { - desc_set_label(desc, NULL); - module_put(chip->owner); - clear_bit(FLAG_REQUESTED, &desc->flags); - 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->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: - if (status) - pr_debug("_gpio_request: gpio-%d (%s) status %d\n", - desc_to_gpio(desc), label ? : "?", status); - spin_unlock_irqrestore(&gpio_lock, flags); - return status; -} -int gpio_request(unsigned gpio, const char *label) -{ - return gpiod_request(gpio_to_desc(gpio), label); + ret = desc_set_label(desc, label ? : "?"); + if (ret) + goto out_clear_bit; + + return 0; + +out_clear_bit: + clear_bit(GPIOD_FLAG_REQUESTED, &desc->flags); + return ret; } -EXPORT_SYMBOL_GPL(gpio_request); -static void gpiod_free(struct gpio_desc *desc) +int gpiod_request(struct gpio_desc *desc, const char *label) { - unsigned long flags; - struct gpio_chip *chip; + int ret = -EPROBE_DEFER; - might_sleep(); + VALIDATE_DESC(desc); - if (!desc) { - WARN_ON(extra_checks); - return; + if (try_module_get(desc->gdev->owner)) { + ret = gpiod_request_commit(desc, label); + if (ret) + module_put(desc->gdev->owner); + else + gpio_device_get(desc->gdev); } - gpiod_unexport(desc); + if (ret) + gpiod_dbg(desc, "%s: status %d\n", __func__, ret); - spin_lock_irqsave(&gpio_lock, flags); + return ret; +} - chip = desc->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); - } - desc_set_label(desc, NULL); - module_put(desc->chip->owner); - 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); - } else - WARN_ON(extra_checks); +static void gpiod_free_commit(struct gpio_desc *desc) +{ + unsigned long flags; - spin_unlock_irqrestore(&gpio_lock, flags); + might_sleep(); + + 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); + 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); + } } -void gpio_free(unsigned gpio) +void gpiod_free(struct gpio_desc *desc) { - gpiod_free(gpio_to_desc(gpio)); + VALIDATE_DESC_VOID(desc); + + gpiod_free_commit(desc); + module_put(desc->gdev->owner); + gpio_device_put(desc->gdev); } -EXPORT_SYMBOL_GPL(gpio_free); /** - * gpio_request_one - request a single GPIO with initial configuration - * @gpio: the GPIO number - * @flags: GPIO configuration as specified by GPIOF_* - * @label: a literal description string of this GPIO + * gpiochip_dup_line_label - Get a copy of the consumer label. + * @gc: GPIO chip controlling this line. + * @offset: Hardware offset of the line. + * + * 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. + * + * Must not be called from atomic context. */ -int gpio_request_one(unsigned gpio, unsigned long flags, const char *label) +char *gpiochip_dup_line_label(struct gpio_chip *gc, unsigned int offset) { struct gpio_desc *desc; - int err; + char *label; - desc = gpio_to_desc(gpio); + desc = gpiochip_get_desc(gc, offset); + if (IS_ERR(desc)) + return NULL; - err = gpiod_request(desc, label); - if (err) - return err; + if (!test_bit(GPIOD_FLAG_REQUESTED, &desc->flags)) + return NULL; - if (flags & GPIOF_OPEN_DRAIN) - set_bit(FLAG_OPEN_DRAIN, &desc->flags); + guard(srcu)(&desc->gdev->desc_srcu); - if (flags & GPIOF_OPEN_SOURCE) - set_bit(FLAG_OPEN_SOURCE, &desc->flags); + label = kstrdup(gpiod_get_label(desc), GFP_KERNEL); + if (!label) + return ERR_PTR(-ENOMEM); - if (flags & GPIOF_DIR_IN) - err = gpiod_direction_input(desc); - else - err = gpiod_direction_output(desc, - (flags & GPIOF_INIT_HIGH) ? 1 : 0); + return label; +} +EXPORT_SYMBOL_GPL(gpiochip_dup_line_label); - if (err) - goto free_gpio; +static inline const char *function_name_or_default(const char *con_id) +{ + return con_id ?: "(default)"; +} - if (flags & GPIOF_EXPORT) { - err = gpiod_export(desc, flags & GPIOF_EXPORT_CHANGEABLE); - if (err) - goto free_gpio; +/** + * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor + * @gc: GPIO chip + * @hwnum: hardware number of the GPIO for which to request the descriptor + * @label: label for the GPIO + * @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 + * function will not increase reference count of the GPIO chip module. This + * allows the GPIO chip module to be unloaded as needed (we assume that the + * GPIO chip driver handles freeing the GPIOs it has requested). + * + * Returns: + * 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 *gc, + unsigned int hwnum, + const char *label, + enum gpio_lookup_flags lflags, + enum gpiod_flags dflags) +{ + struct gpio_desc *desc = gpiochip_get_desc(gc, hwnum); + const char *name = function_name_or_default(label); + int ret; + + if (IS_ERR(desc)) { + gpiochip_err(gc, "failed to get GPIO %s descriptor\n", name); + return desc; } - return 0; + ret = gpiod_request_commit(desc, label); + if (ret < 0) + return ERR_PTR(ret); - free_gpio: - gpiod_free(desc); - return err; + ret = gpiod_configure_flags(desc, label, lflags, dflags); + if (ret) { + gpiod_free_commit(desc); + 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(gpio_request_one); +EXPORT_SYMBOL_GPL(gpiochip_request_own_desc); /** - * gpio_request_array - request multiple GPIOs in a single call - * @array: array of the 'struct gpio' - * @num: how many GPIOs in the array + * gpiochip_free_own_desc - Free GPIO requested by the chip driver + * @desc: GPIO descriptor to free + * + * Function frees the given GPIO requested previously with + * gpiochip_request_own_desc(). + */ +void gpiochip_free_own_desc(struct gpio_desc *desc) +{ + if (desc) + gpiod_free_commit(desc); +} +EXPORT_SYMBOL_GPL(gpiochip_free_own_desc); + +/* + * Drivers MUST set GPIO direction before making get/set calls. In + * some cases this is done in early boot, before IRQs are enabled. + * + * As a rule these aren't called more than once (except for drivers + * using the open-drain emulation idiom) so these are natural places + * to accumulate extra debugging checks. Note that we can't (yet) + * rely on gpio_request() having been called beforehand. */ -int gpio_request_array(const struct gpio *array, size_t num) + +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) { - int i, err; + unsigned long config; - for (i = 0; i < num; i++, array++) { - err = gpio_request_one(array->gpio, array->flags, array->label); - if (err) - goto err_free; + 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; +} -err_free: - while (i--) - gpio_free((--array)->gpio); - return err; +static int gpio_set_config(struct gpio_desc *desc, enum pin_config_param mode) +{ + return gpio_set_config_with_argument(desc, mode, 0); } -EXPORT_SYMBOL_GPL(gpio_request_array); -/** - * gpio_free_array - release multiple GPIOs in a single call - * @array: array of the 'struct gpio' - * @num: how many GPIOs in the array - */ -void gpio_free_array(const struct gpio *array, size_t num) +static int gpio_set_bias(struct gpio_desc *desc) { - while (num--) - gpio_free((array++)->gpio); + 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); } -EXPORT_SYMBOL_GPL(gpio_free_array); /** - * gpiochip_is_requested - return string iff signal was requested - * @chip: controller managing the signal - * @offset: of signal within controller's 0..(ngpio - 1) range + * gpio_set_debounce_timeout() - Set debounce timeout + * @desc: GPIO descriptor to set the debounce timeout + * @debounce: Debounce timeout in microseconds * - * Returns NULL if the GPIO is not currently requested, else a string. - * If debugfs support is enabled, the string returned is the label passed - * to gpio_request(); otherwise it is a meaningless constant. + * The function calls the certain GPIO driver to set debounce timeout + * in the hardware. * - * 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. + * Returns: + * 0 on success, or negative errno on failure. */ -const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset) +int gpio_set_debounce_timeout(struct gpio_desc *desc, unsigned int debounce) { - struct gpio_desc *desc; + int ret; - if (!GPIO_OFFSET_VALID(chip, offset)) - return NULL; + 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); - desc = &chip->desc[offset]; + return ret; +} - if (test_bit(FLAG_REQUESTED, &desc->flags) == 0) - return NULL; -#ifdef CONFIG_DEBUG_FS - return desc->label; -#else - return "?"; -#endif +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; } -EXPORT_SYMBOL_GPL(gpiochip_is_requested); +static int gpiochip_direction_output(struct gpio_chip *gc, unsigned int offset, + int value) +{ + int ret; -/* Drivers MUST set GPIO direction before making get/set calls. In - * some cases this is done in early boot, before IRQs are enabled. + 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 * - * As a rule these aren't called more than once (except for drivers - * using the open-drain emulation idiom) so these are natural places - * to accumulate extra debugging checks. Note that we can't (yet) - * rely on gpio_request() having been called beforehand. + * Set the direction of the passed GPIO to input, such as gpiod_get_value() can + * be called safely on it. + * + * Returns: + * 0 on success, or negative errno on failure. */ +int gpiod_direction_input(struct gpio_desc *desc) +{ + int ret; + + VALIDATE_DESC(desc); + + 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); -static int gpiod_direction_input(struct gpio_desc *desc) +int gpiod_direction_input_nonotify(struct gpio_desc *desc) { - unsigned long flags; - struct gpio_chip *chip; - int status = -EINVAL; - int offset; + int ret = 0, dir; - if (!desc) { - pr_warn("%s: invalid GPIO\n", __func__); - return -EINVAL; + 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 (!guard.gc->get && guard.gc->direction_input) { + gpiod_warn(desc, + "%s: missing get() but have direction_input()\n", + __func__); + return -EIO; + } + + /* + * If we have a .direction_input() callback, things are simple, + * just call it. Else we are some input-only chip so try to check the + * direction (if .get_direction() is supported) else we silently + * assume we are in input mode after this. + */ + 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); } - spin_lock_irqsave(&gpio_lock, flags); + trace_gpio_direction(desc_to_gpio(desc), 1, ret); - chip = desc->chip; - if (!chip || !chip->get || !chip->direction_input) - goto fail; - status = gpio_ensure_requested(desc); - if (status < 0) - goto fail; + return ret; +} - /* now we know the gpio is valid and chip won't vanish */ +static int gpiochip_set(struct gpio_chip *gc, unsigned int offset, int value) +{ + int ret; - spin_unlock_irqrestore(&gpio_lock, flags); + lockdep_assert_held(&gc->gpiodev->srcu); - might_sleep_if(chip->can_sleep); + if (WARN_ON(unlikely(!gc->set))) + return -EOPNOTSUPP; - offset = gpio_chip_hwgpio(desc); - if (status) { - status = chip->request(chip, offset); - if (status < 0) { - pr_debug("GPIO-%d: chip request fail, %d\n", - desc_to_gpio(desc), status); - /* and it's not available to anyone else ... - * gpio_request() is the fully clean solution. - */ - goto lose; + 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) +{ + 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 (!guard.gc->set && !guard.gc->direction_output) { + gpiod_warn(desc, + "%s: missing set() and direction_output() operations\n", + __func__); + return -EIO; + } + + 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 (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. + */ + ret = gpiochip_set(guard.gc, gpiod_hwgpio(desc), val); + if (ret) + return ret; } - status = chip->direction_input(chip, offset); - if (status == 0) - clear_bit(FLAG_IS_OUT, &desc->flags); + if (!ret) + 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; +} - trace_gpio_direction(desc_to_gpio(desc), 1, status); -lose: - return status; -fail: - spin_unlock_irqrestore(&gpio_lock, flags); - if (status) - pr_debug("%s: gpio-%d status %d\n", __func__, - desc_to_gpio(desc), status); - return status; +/** + * gpiod_direction_output_raw - set the GPIO direction to output + * @desc: GPIO to set to output + * @value: initial output value of the GPIO + * + * Set the direction of the passed GPIO to output, such as gpiod_set_value() can + * 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. + * + * 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); + + 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); -int gpio_direction_input(unsigned gpio) +/** + * gpiod_direction_output - set the GPIO direction to output + * @desc: GPIO to set to output + * @value: initial output value of the GPIO + * + * Set the direction of the passed GPIO to output, such as gpiod_set_value() can + * be called safely on it. The initial value of the output must be specified + * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into + * account. + * + * Returns: + * 0 on success, or negative errno on failure. + */ +int gpiod_direction_output(struct gpio_desc *desc, int value) { - return gpiod_direction_input(gpio_to_desc(gpio)); + int ret; + + VALIDATE_DESC(desc); + + 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(gpio_direction_input); +EXPORT_SYMBOL_GPL(gpiod_direction_output); -static int gpiod_direction_output(struct gpio_desc *desc, int value) +int gpiod_direction_output_nonotify(struct gpio_desc *desc, int value) { - unsigned long flags; - struct gpio_chip *chip; - int status = -EINVAL; - int offset; + unsigned long flags; + int ret; - if (!desc) { - pr_warn("%s: invalid GPIO\n", __func__); - return -EINVAL; - } + flags = READ_ONCE(desc->flags); - /* Open drain pin should not be driven to 1 */ - if (value && test_bit(FLAG_OPEN_DRAIN, &desc->flags)) - return gpiod_direction_input(desc); + 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(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; + } - /* Open source pin should not be driven to 0 */ - if (!value && test_bit(FLAG_OPEN_SOURCE, &desc->flags)) - return gpiod_direction_input(desc); + if (test_bit(GPIOD_FLAG_OPEN_DRAIN, &flags)) { + /* First see if we can enable open drain in hardware */ + 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) + 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) + goto set_output_flag; + } else { + gpio_set_config(desc, PIN_CONFIG_DRIVE_PUSH_PULL); + } - spin_lock_irqsave(&gpio_lock, flags); +set_output_value: + ret = gpio_set_bias(desc); + if (ret) + return ret; + return gpiod_direction_output_raw_commit(desc, value); - chip = desc->chip; - if (!chip || !chip->set || !chip->direction_output) - goto fail; - status = gpio_ensure_requested(desc); - if (status < 0) - goto fail; +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; +} - /* now we know the gpio is valid and chip won't vanish */ +#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; - spin_unlock_irqrestore(&gpio_lock, flags); + VALIDATE_DESC(desc); - might_sleep_if(chip->can_sleep); + CLASS(gpio_chip_guard, guard)(desc); + if (!guard.gc) + return -ENODEV; - offset = gpio_chip_hwgpio(desc); - if (status) { - status = chip->request(chip, offset); - if (status < 0) { - pr_debug("GPIO-%d: chip request fail, %d\n", - desc_to_gpio(desc), status); - /* and it's not available to anyone else ... - * gpio_request() is the fully clean solution. - */ - goto lose; - } + if (!guard.gc->en_hw_timestamp) { + gpiod_warn(desc, "%s: hw ts not supported\n", __func__); + return -ENOTSUPP; } - status = chip->direction_output(chip, offset, value); - if (status == 0) - set_bit(FLAG_IS_OUT, &desc->flags); - trace_gpio_value(desc_to_gpio(desc), 0, value); - trace_gpio_direction(desc_to_gpio(desc), 0, status); -lose: - return status; -fail: - spin_unlock_irqrestore(&gpio_lock, flags); - if (status) - pr_debug("%s: gpio-%d status %d\n", __func__, - desc_to_gpio(desc), status); - return status; + 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); -int gpio_direction_output(unsigned gpio, int value) +/** + * 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) { - return gpiod_direction_output(gpio_to_desc(gpio), value); + 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(gpio_direction_output); +EXPORT_SYMBOL_GPL(gpiod_disable_hw_timestamp_ns); +#endif /* CONFIG_HTE */ /** - * gpio_set_debounce - sets @debounce time for a @gpio - * @gpio: the gpio to set debounce time - * @debounce: debounce time is microseconds + * 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. */ -static int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce) +int gpiod_set_config(struct gpio_desc *desc, unsigned long config) { - unsigned long flags; - struct gpio_chip *chip; - int status = -EINVAL; - int offset; + int ret; - if (!desc) { - pr_warn("%s: invalid GPIO\n", __func__); - return -EINVAL; + 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; + } } - spin_lock_irqsave(&gpio_lock, flags); + return ret; +} +EXPORT_SYMBOL_GPL(gpiod_set_config); + +/** + * gpiod_set_debounce - sets @debounce time for a GPIO + * @desc: descriptor of the GPIO for which to set debounce time + * @debounce: debounce time in microseconds + * + * Returns: + * 0 on success, %-ENOTSUPP if the controller doesn't support setting the + * debounce time. + */ +int gpiod_set_debounce(struct gpio_desc *desc, unsigned int debounce) +{ + unsigned long config; + + config = pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE, debounce); + return gpiod_set_config(desc, config); +} +EXPORT_SYMBOL_GPL(gpiod_set_debounce); - chip = desc->chip; - if (!chip || !chip->set || !chip->set_debounce) - goto fail; +/** + * gpiod_set_transitory - Lose or retain GPIO state on suspend or reset + * @desc: descriptor of the GPIO for which to configure persistence + * @transitory: True to lose state on suspend or reset, false for persistence + * + * Returns: + * 0 on success, otherwise a negative error code. + */ +int gpiod_set_transitory(struct gpio_desc *desc, bool transitory) +{ + VALIDATE_DESC(desc); + /* + * Handle GPIOD_FLAG_TRANSITORY first, enabling queries to gpiolib for + * persistence state. + */ + assign_bit(GPIOD_FLAG_TRANSITORY, &desc->flags, transitory); - status = gpio_ensure_requested(desc); - if (status < 0) - goto fail; + /* If the driver supports it, set the persistence state now */ + return gpio_set_config_with_argument_optional(desc, + PIN_CONFIG_PERSIST_STATE, + !transitory); +} - /* now we know the gpio is valid and chip won't vanish */ +/** + * 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. + */ +int gpiod_is_active_low(const struct gpio_desc *desc) +{ + VALIDATE_DESC(desc); + return test_bit(GPIOD_FLAG_ACTIVE_LOW, &desc->flags); +} +EXPORT_SYMBOL_GPL(gpiod_is_active_low); - spin_unlock_irqrestore(&gpio_lock, flags); +/** + * 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); - might_sleep_if(chip->can_sleep); +static int gpiochip_get(struct gpio_chip *gc, unsigned int offset) +{ + int ret; - offset = gpio_chip_hwgpio(desc); - return chip->set_debounce(chip, offset, debounce); + lockdep_assert_held(&gc->gpiodev->srcu); -fail: - spin_unlock_irqrestore(&gpio_lock, flags); - if (status) - pr_debug("%s: gpio-%d status %d\n", __func__, - desc_to_gpio(desc), status); + /* Make sure this is called after checking for gc->get(). */ + ret = gc->get(gc, offset); + if (ret > 1) + ret = -EBADE; - return status; + return ret; } -int gpio_set_debounce(unsigned gpio, unsigned debounce) +static int gpio_chip_get_value(struct gpio_chip *gc, const struct gpio_desc *desc) { - return gpiod_set_debounce(gpio_to_desc(gpio), debounce); + return gc->get ? gpiochip_get(gc, gpiod_hwgpio(desc)) : -EIO; } -EXPORT_SYMBOL_GPL(gpio_set_debounce); /* I/O calls are only valid after configuration completed; the relevant * "is this a valid GPIO" error checks should already have been done. @@ -1826,341 +3304,2152 @@ EXPORT_SYMBOL_GPL(gpio_set_debounce); * that the GPIO was actually requested. */ +static int gpiod_get_raw_value_commit(const struct gpio_desc *desc) +{ + struct gpio_device *gdev; + struct gpio_chip *gc; + int value; + + /* 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 *gc, + unsigned long *mask, unsigned long *bits) +{ + 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, gc->ngpio) { + value = gpiochip_get(gc, i); + if (value < 0) + return value; + __assign_bit(i, bits, value); + } + return 0; + } + 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) +{ + struct gpio_chip *gc; + int ret, i = 0; + + /* + * Validate array_info against desc_array and its size. + * It should immediately follow desc_array if both + * have been obtained from the same gpiod_get_array() call. + */ + if (array_info && array_info->desc == desc_array && + array_size <= array_info->size && + (void *)array_info == desc_array + array_info->size) { + if (!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; + + ret = gpio_chip_get_multiple(gc, array_info->get_mask, + value_bitmap); + 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); + + 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) { + DECLARE_BITMAP(fastpath_mask, FASTPATH_NGPIO); + DECLARE_BITMAP(fastpath_bits, FASTPATH_NGPIO); + unsigned long *mask, *bits; + int first, j; + + 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 { + 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; + } + } + + bitmap_zero(mask, guard.gc->ngpio); + + if (!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 = gpiod_hwgpio(desc); + + __set_bit(hwgpio, mask); + i++; + + if (array_info) + i = find_next_zero_bit(array_info->get_mask, + array_size, i); + } while ((i < array_size) && + gpio_device_chip_cmp(desc_array[i]->gdev, guard.gc)); + + ret = gpio_chip_get_multiple(guard.gc, mask, bits); + if (ret) { + 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 = gpiod_hwgpio(desc); + int value = test_bit(hwgpio, bits); + + 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); + j++; + + if (array_info) + j = find_next_zero_bit(array_info->get_mask, i, + j); + } + + if (mask != fastpath_mask) + bitmap_free(mask); + if (bits != fastpath_bits) + bitmap_free(bits); + } + return 0; +} + /** - * __gpio_get_value() - return a gpio's value - * @gpio: gpio whose value will be returned - * Context: any + * gpiod_get_raw_value() - return a gpio's raw value + * @desc: gpio whose value will be returned + * + * 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 is used directly or indirectly to implement gpio_get_value(). - * It returns the zero or nonzero value provided by the associated - * gpio_chip.get() method; or zero if no such method is provided. + * This function can be called from contexts where we cannot sleep, and will + * complain if the GPIO chip functions potentially sleep. */ -static int gpiod_get_value(const struct gpio_desc *desc) +int gpiod_get_raw_value(const struct gpio_desc *desc) +{ + VALIDATE_DESC(desc); + /* 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); + +/** + * gpiod_get_value() - return a gpio's value + * @desc: gpio whose value will be returned + * + * Returns: + * The GPIO's logical value, i.e. taking the ACTIVE_LOW status into + * account, or negative errno on failure. + * + * 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) { - struct gpio_chip *chip; int value; - int offset; - if (!desc) - return 0; - chip = desc->chip; - offset = gpio_chip_hwgpio(desc); - /* Should be using gpio_get_value_cansleep() */ - WARN_ON(chip->can_sleep); - value = chip->get ? chip->get(chip, offset) : 0; - trace_gpio_value(desc_to_gpio(desc), 1, value); + VALIDATE_DESC(desc); + /* 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(GPIOD_FLAG_ACTIVE_LOW, &desc->flags)) + value = !value; + return value; } +EXPORT_SYMBOL_GPL(gpiod_get_value); -int __gpio_get_value(unsigned gpio) +/** + * gpiod_get_raw_array_value() - read raw values from an array of GPIOs + * @array_size: number of elements in the descriptor array / value bitmap + * @desc_array: array of GPIO descriptors whose values will be read + * @array_info: information on applicability of fast bitmap processing path + * @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. + * + * 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, + struct gpio_array *array_info, + unsigned long *value_bitmap) { - return gpiod_get_value(gpio_to_desc(gpio)); + if (!desc_array) + return -EINVAL; + return gpiod_get_array_value_complex(true, false, array_size, + desc_array, array_info, + value_bitmap); +} +EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value); + +/** + * gpiod_get_array_value() - read values from an array of GPIOs + * @array_size: number of elements in the descriptor array / value bitmap + * @desc_array: array of GPIO descriptors whose values will be read + * @array_info: information on applicability of fast bitmap processing path + * @value_bitmap: bitmap to store the read values + * + * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status + * into account. + * + * 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, + struct gpio_array *array_info, + unsigned long *value_bitmap) +{ + if (!desc_array) + return -EINVAL; + return gpiod_get_array_value_complex(false, false, array_size, + desc_array, array_info, + value_bitmap); } -EXPORT_SYMBOL_GPL(__gpio_get_value); +EXPORT_SYMBOL_GPL(gpiod_get_array_value); /* - * _gpio_set_open_drain_value() - Set the open drain gpio's value. - * @gpio: Gpio whose state need to be set. - * @chip: Gpio chip. - * @value: Non-zero for setting it HIGH otherise it will set to LOW. + * gpio_set_open_drain_value_commit() - Set the open drain gpio's 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(struct gpio_desc *desc, int value) +static int gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value) { - int err = 0; - struct gpio_chip *chip = desc->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) - pr_err("%s: Error in set_value for open drain gpio%d err %d\n", - __func__, desc_to_gpio(desc), err); + 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__, ret); + + return ret; } /* - * _gpio_set_open_source() - Set the open source gpio's value. - * @gpio: Gpio whose state need to be set. - * @chip: Gpio chip. - * @value: Non-zero for setting it HIGH otherise it will set to LOW. + * _gpio_set_open_source_value() - Set the open source gpio's 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(struct gpio_desc *desc, int value) +static int gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value) { - int err = 0; - struct gpio_chip *chip = desc->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) - pr_err("%s: Error in set_value for open source gpio%d err %d\n", - __func__, desc_to_gpio(desc), err); + 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__, ret); + + return ret; +} + +static int gpiod_set_raw_value_commit(struct gpio_desc *desc, bool value) +{ + if (unlikely(!test_bit(GPIOD_FLAG_IS_OUT, &desc->flags))) + return -EPERM; + + CLASS(gpio_chip_guard, guard)(desc); + if (!guard.gc) + return -ENODEV; + + trace_gpio_value(desc_to_gpio(desc), 0, 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 int gpiochip_set_multiple(struct gpio_chip *gc, + unsigned long *mask, unsigned long *bits) +{ + 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; + + 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, + unsigned int array_size, + struct gpio_desc **desc_array, + struct gpio_array *array_info, + unsigned long *value_bitmap) +{ + struct gpio_chip *gc; + int i = 0, ret; + + /* + * Validate array_info against desc_array and its size. + * It should immediately follow desc_array if both + * have been obtained from the same gpiod_get_array() call. + */ + if (array_info && array_info->desc == desc_array && + array_size <= array_info->size && + (void *)array_info == desc_array + array_info->size) { + if (!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); + + 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) { + DECLARE_BITMAP(fastpath_mask, FASTPATH_NGPIO); + DECLARE_BITMAP(fastpath_bits, FASTPATH_NGPIO); + unsigned long *mask, *bits; + int count = 0; + + 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 { + 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; + } + } + + bitmap_zero(mask, guard.gc->ngpio); + + if (!can_sleep) + WARN_ON(guard.gc->can_sleep); + + do { + struct gpio_desc *desc = desc_array[i]; + 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 + * inverted inside the fast path, skip them. + */ + if (!raw && !(array_info && + test_bit(i, array_info->invert_mask)) && + 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(GPIOD_FLAG_OPEN_DRAIN, &desc->flags) && !raw) { + gpio_set_open_drain_value_commit(desc, value); + } else if (test_bit(GPIOD_FLAG_OPEN_SOURCE, &desc->flags) && !raw) { + gpio_set_open_source_value_commit(desc, value); + } else { + __set_bit(hwgpio, mask); + __assign_bit(hwgpio, bits, value); + count++; + } + i++; + + if (array_info) + i = find_next_zero_bit(array_info->set_mask, + array_size, i); + } while ((i < array_size) && + gpio_device_chip_cmp(desc_array[i]->gdev, guard.gc)); + /* push collected bits to outputs */ + if (count != 0) { + ret = gpiochip_set_multiple(guard.gc, mask, bits); + if (ret) + return ret; + } + + if (mask != fastpath_mask) + bitmap_free(mask); + if (bits != fastpath_bits) + bitmap_free(bits); + } + return 0; } /** - * __gpio_set_value() - assign a gpio's value - * @gpio: gpio whose value will be assigned + * gpiod_set_raw_value() - assign a gpio's raw value + * @desc: gpio whose value will be assigned * @value: value to assign - * Context: any * - * This is used directly or indirectly to implement gpio_set_value(). - * It invokes the associated gpio_chip.set() method. + * Set the raw value of the GPIO, i.e. the value of its physical line without + * regard for its ACTIVE_LOW status. + * + * 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. */ -static void gpiod_set_value(struct gpio_desc *desc, int value) +int gpiod_set_raw_value(struct gpio_desc *desc, int value) { - struct gpio_chip *chip; + 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); - if (!desc) - return; - chip = desc->chip; - /* Should be using gpio_set_value_cansleep() */ - WARN_ON(chip->can_sleep); - trace_gpio_value(desc_to_gpio(desc), 0, value); - if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) - _gpio_set_open_drain_value(desc, value); - else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) - _gpio_set_open_source_value(desc, value); - else - chip->set(chip, gpio_chip_hwgpio(desc), value); +/** + * gpiod_set_value_nocheck() - set a GPIO line value without checking + * @desc: the descriptor to set the value on + * @value: value to set + * + * 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 int gpiod_set_value_nocheck(struct gpio_desc *desc, int value) +{ + if (test_bit(GPIOD_FLAG_ACTIVE_LOW, &desc->flags)) + value = !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); } -void __gpio_set_value(unsigned gpio, int value) +/** + * gpiod_set_value() - assign a gpio's value + * @desc: gpio whose value will be assigned + * @value: value to assign + * + * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW, + * OPEN_DRAIN and OPEN_SOURCE flags into account. + * + * 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. + */ +int gpiod_set_value(struct gpio_desc *desc, int value) { - return gpiod_set_value(gpio_to_desc(gpio), 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(__gpio_set_value); +EXPORT_SYMBOL_GPL(gpiod_set_value); /** - * __gpio_cansleep() - report whether gpio value access will sleep - * @gpio: gpio in question - * Context: any + * gpiod_set_raw_array_value() - assign values to an array of GPIOs + * @array_size: number of elements in the descriptor array / value bitmap + * @desc_array: array of GPIO descriptors whose values will be assigned + * @array_info: information on applicability of fast bitmap processing path + * @value_bitmap: bitmap of values to assign + * + * Set the raw values of the GPIOs, i.e. the values of the physical lines + * without regard for their ACTIVE_LOW status. + * + * This function can be called from contexts where we cannot sleep, and will + * complain if the GPIO chip functions potentially sleep. * - * This is used directly or indirectly to implement gpio_cansleep(). It - * returns nonzero if access reading or writing the GPIO value can sleep. + * Returns: + * 0 on success, or negative errno on failure. */ -static int gpiod_cansleep(const struct gpio_desc *desc) +int gpiod_set_raw_array_value(unsigned int array_size, + struct gpio_desc **desc_array, + struct gpio_array *array_info, + unsigned long *value_bitmap) { - if (!desc) - return 0; - /* only call this on GPIOs that are valid! */ - return desc->chip->can_sleep; + if (!desc_array) + return -EINVAL; + return gpiod_set_array_value_complex(true, false, array_size, + desc_array, array_info, value_bitmap); } +EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value); -int __gpio_cansleep(unsigned gpio) +/** + * gpiod_set_array_value() - assign values to an array of GPIOs + * @array_size: number of elements in the descriptor array / value bitmap + * @desc_array: array of GPIO descriptors whose values will be assigned + * @array_info: information on applicability of fast bitmap processing path + * @value_bitmap: bitmap of values to assign + * + * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status + * into account. + * + * 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, + struct gpio_array *array_info, + unsigned long *value_bitmap) { - return gpiod_cansleep(gpio_to_desc(gpio)); + if (!desc_array) + return -EINVAL; + return gpiod_set_array_value_complex(false, false, array_size, + desc_array, array_info, + value_bitmap); } -EXPORT_SYMBOL_GPL(__gpio_cansleep); +EXPORT_SYMBOL_GPL(gpiod_set_array_value); /** - * __gpio_to_irq() - return the IRQ corresponding to a GPIO - * @gpio: gpio whose IRQ will be returned (already requested) - * Context: any + * gpiod_cansleep() - report whether gpio value access may sleep + * @desc: gpio to check * - * This is used directly or indirectly to implement gpio_to_irq(). - * It returns the number of the IRQ signaled by this (input) GPIO, - * or a negative errno. + * Returns: + * 0 for non-sleepable, 1 for sleepable, or an error code in case of error. */ -static int gpiod_to_irq(const struct gpio_desc *desc) +int gpiod_cansleep(const struct gpio_desc *desc) { - struct gpio_chip *chip; - int offset; + VALIDATE_DESC(desc); + return desc->gdev->can_sleep; +} +EXPORT_SYMBOL_GPL(gpiod_cansleep); - if (!desc) +/** + * 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); + + ret = desc_set_label(desc, name); + if (ret == 0) + gpiod_line_state_notify(desc, GPIO_V2_LINE_CHANGED_CONFIG); + + 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) + * + * 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_device *gdev; + struct gpio_chip *gc; + int offset; + int ret; + + ret = validate_desc(desc, __func__); + if (ret <= 0) return -EINVAL; - chip = desc->chip; - offset = gpio_chip_hwgpio(desc); - return chip->to_irq ? chip->to_irq(chip, offset) : -ENXIO; + + 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; + + offset = gpiod_hwgpio(desc); + if (gc->to_irq) { + ret = gc->to_irq(gc, offset); + if (ret) + return ret; + + /* 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); -int __gpio_to_irq(unsigned gpio) +/** + * gpiochip_lock_as_irq() - lock a GPIO to be used as IRQ + * @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 *gc, unsigned int offset) { - return gpiod_to_irq(gpio_to_desc(gpio)); + struct gpio_desc *desc; + + desc = gpiochip_get_desc(gc, offset); + if (IS_ERR(desc)) + return PTR_ERR(desc); + + /* + * If it's fast: flush the direction setting if something changed + * behind our back + */ + if (!gc->can_sleep && gc->get_direction) { + int dir = gpiod_get_direction(desc); + + if (dir < 0) { + gpiochip_err(gc, "%s: cannot get GPIO direction\n", + __func__); + return dir; + } + } + + /* 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(GPIOD_FLAG_USED_AS_IRQ, &desc->flags); + set_bit(GPIOD_FLAG_IRQ_IS_ENABLED, &desc->flags); + + return 0; } -EXPORT_SYMBOL_GPL(__gpio_to_irq); +EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq); + +/** + * gpiochip_unlock_as_irq() - unlock a GPIO used as IRQ + * @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 *gc, unsigned int offset) +{ + struct gpio_desc *desc; + desc = gpiochip_get_desc(gc, offset); + if (IS_ERR(desc)) + return; -/* There's no value in making it easy to inline GPIO calls that may sleep. - * Common examples include ones connected to I2C or SPI chips. + 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 *gc, unsigned int offset) +{ + struct gpio_desc *desc = gpiochip_get_desc(gc, offset); + + if (!IS_ERR(desc) && + !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 *gc, unsigned int offset) +{ + struct gpio_desc *desc = gpiochip_get_desc(gc, offset); + + if (!IS_ERR(desc) && + !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 *gc, unsigned int offset) +{ + if (offset >= gc->ngpio) + return false; + + 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 *gc, unsigned int offset) +{ + int ret; + + if (!try_module_get(gc->gpiodev->owner)) + return -ENODEV; + + ret = gpiochip_lock_as_irq(gc, offset); + if (ret) { + 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 *gc, unsigned int offset) +{ + 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 *gc, unsigned int offset) +{ + if (offset >= gc->ngpio) + return false; + + 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 *gc, unsigned int offset) +{ + if (offset >= gc->ngpio) + return false; + + 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 *gc, unsigned int offset) +{ + if (offset >= gc->ngpio) + return false; + + return !test_bit(GPIOD_FLAG_TRANSITORY, &gc->gpiodev->descs[offset].flags); +} +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 + * + * 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(); + VALIDATE_DESC(desc); + return gpiod_get_raw_value_commit(desc); +} +EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep); -static int gpiod_get_value_cansleep(const struct gpio_desc *desc) +/** + * gpiod_get_value_cansleep() - return a gpio's value + * @desc: gpio whose value will be returned + * + * 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. + */ +int gpiod_get_value_cansleep(const struct gpio_desc *desc) { - struct gpio_chip *chip; int value; - int offset; - might_sleep_if(extra_checks); - if (!desc) - return 0; - chip = desc->chip; - offset = gpio_chip_hwgpio(desc); - value = chip->get ? chip->get(chip, offset) : 0; - trace_gpio_value(desc_to_gpio(desc), 1, value); + might_sleep(); + VALIDATE_DESC(desc); + value = gpiod_get_raw_value_commit(desc); + if (value < 0) + return value; + + if (test_bit(GPIOD_FLAG_ACTIVE_LOW, &desc->flags)) + value = !value; + return value; } +EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep); -int gpio_get_value_cansleep(unsigned gpio) +/** + * gpiod_get_raw_array_value_cansleep() - read raw values from an array of GPIOs + * @array_size: number of elements in the descriptor array / value bitmap + * @desc_array: array of GPIO descriptors whose values will be read + * @array_info: information on applicability of fast bitmap processing path + * @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. + * + * 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) { - return gpiod_get_value_cansleep(gpio_to_desc(gpio)); + might_sleep(); + if (!desc_array) + return -EINVAL; + return gpiod_get_array_value_complex(true, true, array_size, + desc_array, array_info, + value_bitmap); } -EXPORT_SYMBOL_GPL(gpio_get_value_cansleep); +EXPORT_SYMBOL_GPL(gpiod_get_raw_array_value_cansleep); -static void gpiod_set_value_cansleep(struct gpio_desc *desc, int value) +/** + * gpiod_get_array_value_cansleep() - read values from an array of GPIOs + * @array_size: number of elements in the descriptor array / value bitmap + * @desc_array: array of GPIO descriptors whose values will be read + * @array_info: information on applicability of fast bitmap processing path + * @value_bitmap: bitmap to store the read values + * + * Read the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status + * 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) { - struct gpio_chip *chip; + might_sleep(); + if (!desc_array) + return -EINVAL; + return gpiod_get_array_value_complex(false, true, array_size, + desc_array, array_info, + value_bitmap); +} +EXPORT_SYMBOL_GPL(gpiod_get_array_value_cansleep); - might_sleep_if(extra_checks); - if (!desc) +/** + * gpiod_set_raw_value_cansleep() - assign a gpio's raw value + * @desc: gpio whose value will be assigned + * @value: value to assign + * + * Set the raw value of the GPIO, i.e. the value of its physical line without + * 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. + */ +int gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value) +{ + might_sleep(); + VALIDATE_DESC(desc); + return gpiod_set_raw_value_commit(desc, value); +} +EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep); + +/** + * gpiod_set_value_cansleep() - assign a gpio's value + * @desc: gpio whose value will be assigned + * @value: value to assign + * + * Set the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into + * account + * + * This function is to be called from contexts that can sleep. + * + * Returns: + * 0 on success, negative error number on failure. + */ +int gpiod_set_value_cansleep(struct gpio_desc *desc, int value) +{ + might_sleep(); + VALIDATE_DESC(desc); + return gpiod_set_value_nocheck(desc, value); +} +EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep); + +/** + * gpiod_set_raw_array_value_cansleep() - assign values to an array of GPIOs + * @array_size: number of elements in the descriptor array / value bitmap + * @desc_array: array of GPIO descriptors whose values will be assigned + * @array_info: information on applicability of fast bitmap processing path + * @value_bitmap: bitmap of values to assign + * + * Set the raw values of the GPIOs, i.e. the values of the physical lines + * 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 (!desc_array) + return -EINVAL; + return gpiod_set_array_value_complex(true, true, array_size, desc_array, + array_info, value_bitmap); +} +EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep); + +/** + * gpiod_add_lookup_tables() - register GPIO device consumers + * @tables: list of tables of consumers to register + * @n: number of tables in the list + */ +void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n) +{ + unsigned int i; + + guard(mutex)(&gpio_lookup_lock); + + for (i = 0; i < n; i++) + list_add_tail(&tables[i]->list, &gpio_lookup_list); +} + +/** + * gpiod_set_array_value_cansleep() - assign values to an array of GPIOs + * @array_size: number of elements in the descriptor array / value bitmap + * @desc_array: array of GPIO descriptors whose values will be assigned + * @array_info: information on applicability of fast bitmap processing path + * @value_bitmap: bitmap of values to assign + * + * Set the logical values of the GPIOs, i.e. taking their ACTIVE_LOW status + * 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 (!desc_array) + return -EINVAL; + return gpiod_set_array_value_complex(false, true, array_size, + desc_array, array_info, + value_bitmap); +} +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) +{ + gpiod_add_lookup_tables(&table, 1); +} +EXPORT_SYMBOL_GPL(gpiod_add_lookup_table); + +/** + * gpiod_remove_lookup_table() - unregister GPIO device consumers + * @table: table of consumers to unregister + */ +void gpiod_remove_lookup_table(struct gpiod_lookup_table *table) +{ + /* Nothing to remove */ + if (!table) return; - chip = desc->chip; - trace_gpio_value(desc_to_gpio(desc), 0, value); - if (test_bit(FLAG_OPEN_DRAIN, &desc->flags)) - _gpio_set_open_drain_value(desc, value); - else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) - _gpio_set_open_source_value(desc, value); + + guard(mutex)(&gpio_lookup_lock); + + list_del(&table->list); +} +EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table); + +/** + * gpiod_add_hogs() - register a set of GPIO hogs from machine code + * @hogs: table of gpio hog entries with a zeroed sentinel at the end + */ +void gpiod_add_hogs(struct gpiod_hog *hogs) +{ + struct gpiod_hog *hog; + + guard(mutex)(&gpio_machine_hogs_mutex); + + for (hog = &hogs[0]; hog->chip_label; hog++) { + list_add_tail(&hog->list, &gpio_machine_hogs); + + /* + * The chip may have been registered earlier, so check if it + * exists and, if so, try to hog the line now. + */ + 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); + } +} +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; + + list_for_each_entry(table, &gpio_lookup_list, list) { + if (table->dev_id && dev_id) { + /* + * Valid strings on both ends, must be identical to have + * a match + */ + if (!strcmp(table->dev_id, dev_id)) + return table; + } else { + /* + * One of the pointers is NULL, so both must be to have + * a match + */ + if (dev_id == table->dev_id) + return table; + } + } + + return NULL; +} + +static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id, + 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->key; p++) { + /* idx must always match exactly */ + if (p->idx != idx) + continue; + + /* If the lookup entry has a con_id, require exact match */ + if (p->con_id && (!con_id || strcmp(p->con_id, con_id))) + continue; + + if (p->chip_hwnum == U16_MAX) { + desc = gpio_name_to_desc(p->key); + if (desc) { + *flags = p->flags; + return desc; + } + + 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->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->key); + return ERR_PTR(-EPROBE_DEFER); + } + + gc = gpio_device_get_chip(gdev); + + if (gc->ngpio <= p->chip_hwnum) { + dev_err(dev, + "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 = gpio_device_get_desc(gdev, p->chip_hwnum); + *flags = p->flags; + + return desc; + } + + return desc; +} + +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; + + scoped_guard(mutex, &gpio_lookup_lock) { + table = gpiod_find_lookup_table(dev); + if (!table) + return -ENOENT; + + 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 + * @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_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); + + return count; +} +EXPORT_SYMBOL_GPL(gpiod_count); + +/** + * gpiod_get - obtain a GPIO for a given GPIO function + * @dev: GPIO consumer, can be NULL for system-global GPIOs + * @con_id: function within the GPIO consumer + * @flags: optional GPIO initialization flags + * + * 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. + */ +struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id, + enum gpiod_flags flags) +{ + return gpiod_get_index(dev, con_id, 0, flags); +} +EXPORT_SYMBOL_GPL(gpiod_get); + +/** + * gpiod_get_optional - obtain an optional GPIO for a given GPIO function + * @dev: GPIO consumer, can be NULL for system-global GPIOs + * @con_id: function within the GPIO consumer + * @flags: optional GPIO initialization flags + * + * 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, + enum gpiod_flags flags) +{ + return gpiod_get_index_optional(dev, con_id, 0, flags); +} +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: 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, -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) +{ + const char *name = function_name_or_default(con_id); + int ret; + + if (lflags & GPIO_ACTIVE_LOW) + set_bit(GPIOD_FLAG_ACTIVE_LOW, &desc->flags); + + if (lflags & GPIO_OPEN_DRAIN) + 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. + * This is necessary for some busses like I2C, but the lookup + * should *REALLY* have specified them as open drain in the + * first place, so print a little warning here. + */ + 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(GPIOD_FLAG_OPEN_SOURCE, &desc->flags); + + 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)) { + gpiod_dbg(desc, "no flags found for GPIO %s\n", name); + return 0; + } + + /* Process flags */ + if (dflags & GPIOD_FLAGS_BIT_DIR_OUT) + ret = gpiod_direction_output_nonotify(desc, + !!(dflags & GPIOD_FLAGS_BIT_DIR_VAL)); else - chip->set(chip, gpio_chip_hwgpio(desc), value); + ret = gpiod_direction_input_nonotify(desc); + + return ret; } -void gpio_set_value_cansleep(unsigned gpio, int value) +/** + * gpiod_get_index - obtain a GPIO from a multi-index GPIO function + * @dev: GPIO consumer, can be NULL for system-global GPIOs + * @con_id: function within the GPIO consumer + * @idx: index of the GPIO to obtain in the consumer + * @flags: optional GPIO initialization flags + * + * This variant of gpiod_get() allows to access GPIOs other than the first + * defined one for functions that define several GPIOs. + * + * 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. + */ +struct gpio_desc *__must_check gpiod_get_index(struct device *dev, + const char *con_id, + unsigned int idx, + enum gpiod_flags flags) { - return gpiod_set_value_cansleep(gpio_to_desc(gpio), value); + struct fwnode_handle *fwnode = dev ? dev_fwnode(dev) : NULL; + const char *devname = dev ? dev_name(dev) : "?"; + const char *label = con_id ?: devname; + + return gpiod_find_and_request(dev, fwnode, con_id, idx, flags, label, true); } -EXPORT_SYMBOL_GPL(gpio_set_value_cansleep); +EXPORT_SYMBOL_GPL(gpiod_get_index); -#ifdef CONFIG_DEBUG_FS +/** + * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO + * function + * @dev: GPIO consumer, can be NULL for system-global GPIOs + * @con_id: function within the GPIO consumer + * @index: index of the GPIO to obtain in the consumer + * @flags: optional GPIO initialization flags + * + * 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, + unsigned int index, + enum gpiod_flags flags) +{ + struct gpio_desc *desc; -static void gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip) + desc = gpiod_get_index(dev, con_id, index, flags); + if (gpiod_not_found(desc)) + return NULL; + + return desc; +} +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: 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) { - unsigned i; - unsigned gpio = chip->base; - struct gpio_desc *gdesc = &chip->desc[0]; - int is_out; + struct gpio_device *gdev = desc->gdev; + struct gpio_desc *local_desc; + int hwnum; + int ret; + + CLASS(gpio_chip_guard, guard)(desc); + if (!guard.gc) + return -ENODEV; + + 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)) { + 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, gdev->label, hwnum, ret); + return ret; + } + + 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 + * @gc: gpio chip to act on + */ +static void gpiochip_free_hogs(struct gpio_chip *gc) +{ + struct gpio_desc *desc; + + for_each_gpio_desc_with_flag(gc, desc, GPIOD_FLAG_IS_HOGGED) + gpiochip_free_own_desc(desc); +} + +/** + * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function + * @dev: GPIO consumer, can be NULL for system-global GPIOs + * @con_id: function within the GPIO consumer + * @flags: optional GPIO initialization flags + * + * This function acquires all the GPIOs defined under a given function. + * + * 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, + enum gpiod_flags flags) +{ + struct gpio_desc *desc; + struct gpio_descs *descs; + struct gpio_device *gdev; + struct gpio_array *array_info = NULL; + 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_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; descs->ndescs++) { + desc = gpiod_get_index(dev, con_id, descs->ndescs, flags); + if (IS_ERR(desc)) { + gpiod_put_array(descs); + return ERR_CAST(desc); + } + + descs->desc[descs->ndescs] = 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 && gpiod_hwgpio(desc) == 0) { + struct gpio_descs *array; + + bitmap_size = BITS_TO_LONGS(gdev->ngpio > count ? + gdev->ngpio : count); + + 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); + } - for (i = 0; i < chip->ngpio; i++, gpio++, gdesc++) { - if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) + descs = array; + + array_info = (void *)descs + descs_size; + array_info->get_mask = array_info->invert_mask + + bitmap_size; + array_info->set_mask = array_info->get_mask + + bitmap_size; + + array_info->desc = descs->desc; + array_info->size = count; + 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; - gpiod_get_direction(gdesc); - is_out = test_bit(FLAG_IS_OUT, &gdesc->flags); - seq_printf(s, " gpio-%-3d (%-20.20s) %s %s", - gpio, gdesc->label, - is_out ? "out" : "in ", - chip->get - ? (chip->get(chip, i) ? "hi" : "lo") - : "? "); - seq_printf(s, "\n"); + /* Unmark array members which don't belong to the 'fast' chip */ + if (array_info->gdev != gdev) { + __clear_bit(descs->ndescs, array_info->get_mask); + __clear_bit(descs->ndescs, array_info->set_mask); + } + /* + * Detect array members which belong to the 'fast' chip + * but their pins are not in hardware order. + */ + 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 + * hardware number is different from its array index. + */ + if (bitmap_full(array_info->get_mask, descs->ndescs)) { + array_info = NULL; + } else { + __clear_bit(descs->ndescs, + array_info->get_mask); + __clear_bit(descs->ndescs, + array_info->set_mask); + } + } else { + dflags = READ_ONCE(desc->flags); + /* Exclude open drain or open source from fast output */ + 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 */ + if (gpiod_is_active_low(desc)) + __set_bit(descs->ndescs, + array_info->invert_mask); + } } + 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->gdev->label, array_info->size, + *array_info->get_mask, *array_info->set_mask, + *array_info->invert_mask); + return descs; } +EXPORT_SYMBOL_GPL(gpiod_get_array); -static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos) +/** + * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO + * function + * @dev: GPIO consumer, can be NULL for system-global GPIOs + * @con_id: function within the GPIO consumer + * @flags: optional GPIO initialization flags + * + * 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, + enum gpiod_flags flags) +{ + struct gpio_descs *descs; + + descs = gpiod_get_array(dev, con_id, flags); + if (gpiod_not_found(descs)) + return NULL; + + return descs; +} +EXPORT_SYMBOL_GPL(gpiod_get_array_optional); + +/** + * gpiod_put - dispose of a GPIO descriptor + * @desc: GPIO descriptor to dispose of + * + * No descriptor can be used after gpiod_put() has been called on it. + */ +void gpiod_put(struct gpio_desc *desc) +{ + gpiod_free(desc); +} +EXPORT_SYMBOL_GPL(gpiod_put); + +/** + * gpiod_put_array - dispose of multiple GPIO descriptors + * @descs: struct gpio_descs containing an array of descriptors + */ +void gpiod_put_array(struct gpio_descs *descs) +{ + unsigned int i; + + for (i = 0; i < descs->ndescs; i++) + gpiod_put(descs->desc[i]); + + kfree(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; + + /* Register GPIO sysfs bus */ + ret = bus_register(&gpio_bus_type); + if (ret < 0) { + pr_err("gpiolib: could not register GPIO bus type\n"); + return ret; + } + + 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); + 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); + +#ifdef CONFIG_DEBUG_FS + +static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev) { + bool active_low, is_irq, is_out; + struct gpio_desc *desc; + unsigned int gpio = 0; + struct gpio_chip *gc; unsigned long flags; - struct gpio_chip *chip = NULL; - loff_t index = *pos; + int value; - s->private = ""; + guard(srcu)(&gdev->srcu); - spin_lock_irqsave(&gpio_lock, flags); - list_for_each_entry(chip, &gpio_chips, list) - if (index-- == 0) { - spin_unlock_irqrestore(&gpio_lock, flags); - return chip; + 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); } - spin_unlock_irqrestore(&gpio_lock, flags); + + gpio++; + } +} + +struct gpiolib_seq_priv { + bool newline; + int idx; +}; + +static void *gpiolib_seq_start(struct seq_file *s, loff_t *pos) +{ + struct gpiolib_seq_priv *priv; + struct gpio_device *gdev; + loff_t index = *pos; + + 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); + + list_for_each_entry_srcu(gdev, &gpio_devices, list, + srcu_read_lock_held(&gpio_devices_srcu)) { + if (index-- == 0) + return gdev; + } return NULL; } static void *gpiolib_seq_next(struct seq_file *s, void *v, loff_t *pos) { - unsigned long flags; - struct gpio_chip *chip = v; - void *ret = NULL; - - spin_lock_irqsave(&gpio_lock, flags); - if (list_is_last(&chip->list, &gpio_chips)) - ret = NULL; - else - ret = list_entry(chip->list.next, struct gpio_chip, list); - spin_unlock_irqrestore(&gpio_lock, flags); + struct gpiolib_seq_priv *priv = s->private; + struct gpio_device *gdev = v, *next; - 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 gpio_chip *chip = v; - struct device *dev; - - seq_printf(s, "%sGPIOs %d-%d", (char *)s->private, - chip->base, chip->base + chip->ngpio - 1); - dev = chip->dev; - if (dev) - seq_printf(s, ", %s/%s", dev->bus ? dev->bus->name : "no-bus", - dev_name(dev)); - if (chip->label) - seq_printf(s, ", %s", chip->label); - if (chip->can_sleep) + struct gpiolib_seq_priv *priv = s->private; + struct gpio_device *gdev = v; + struct gpio_chip *gc; + struct device *parent; + + 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: %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 (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, chip); + 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); |