diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2022-12-15 09:45:51 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-12-15 09:45:51 -0800 |
commit | c0f234ff90a211272138be1611ba53f3155ebd78 (patch) | |
tree | 956c32a903675d690631100ae829e810b4b4515b /drivers/gpio/gpiolib.c | |
parent | 9fa4abc9ad2a18410a7087e6cea15ad1ffb172c6 (diff) | |
parent | 11e47bbd700f31bd1ee9f8863381bc9e741c0e97 (diff) |
Merge tag 'gpio-updates-for-v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux
Pull gpio updates from Bartosz Golaszewski:
"We have a new GPIO multiplexer driver, bunch of driver updates and
refactoring in the core GPIO library.
GPIO core:
- teach gpiolib to work with software nodes for HW description
- remove ARCH_NR_GPIOS treewide as we no longer impose any limit on
the number of GPIOS since the allocation became entirely dynamic
- add support for HW quirks for Cirrus CS42L56 codec, Marvell NFC
controller, Freescale PCIe and Ethernet controller, Himax LCDs and
Mediatek mt2701
- refactor OF quirk code
- some general refactoring of the OF and ACPI code, adding new
helpers, minor tweaks and fixes, making fwnode usage consistent
etc.
GPIO uAPI:
- fix an issue where the user-space can trigger a NULL-pointer
dereference in the kernel by opening a device file, forcing a
driver unbind and then calling one of the syscalls on the
associated file descriptor
New drivers:
- add gpio-latch: a new GPIO multiplexer based on latches connected
to other GPIOs
Driver updates:
- convert i2c GPIO expanders to using .probe_new()
- drop the gpio-sta2x11 driver
- factor out common code for the ACCES IDIO-16 family of controllers
and use this new library wherever applicable in drivers
- add DT support to gpio-hisi
- allow building gpio-davinci as a module and increase its maxItems
property
- add support for a new model to gpio-pca9570
- other minor changes to various drivers"
* tag 'gpio-updates-for-v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux: (66 commits)
gpio: sim: set a limit on the number of GPIOs
gpiolib: protect the GPIO device against being dropped while in use by user-space
gpiolib: cdev: fix NULL-pointer dereferences
gpiolib: Provide to_gpio_device() helper
gpiolib: Unify access to the device properties
gpio: Do not include <linux/kernel.h> when not really needed.
gpio: pcf857x: Convert to i2c's .probe_new()
gpio: pca953x: Convert to i2c's .probe_new()
gpio: max732x: Convert to i2c's .probe_new()
dt-bindings: gpio: gpio-davinci: Increase maxItems in gpio-line-names
gpiolib: ensure that fwnode is properly set
gpio: sl28cpld: Replace irqchip mask_invert with unmask_base
gpiolib: of: Use correct fwnode for DT-probed chips
gpiolib: of: Drop redundant check in of_mm_gpiochip_remove()
gpiolib: of: Prepare of_mm_gpiochip_add_data() for fwnode
gpiolib: add support for software nodes
gpiolib: consolidate GPIO lookups
gpiolib: acpi: avoid leaking ACPI details into upper gpiolib layers
gpiolib: acpi: teach acpi_find_gpio() to handle data-only nodes
gpiolib: acpi: change acpi_find_gpio() to accept firmware node
...
Diffstat (limited to 'drivers/gpio/gpiolib.c')
-rw-r--r-- | drivers/gpio/gpiolib.c | 295 |
1 files changed, 155 insertions, 140 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index a70522aef355..5a66d9616d7c 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -26,6 +26,7 @@ #include "gpiolib.h" #include "gpiolib-of.h" #include "gpiolib-acpi.h" +#include "gpiolib-swnode.h" #include "gpiolib-cdev.h" #include "gpiolib-sysfs.h" @@ -183,14 +184,14 @@ EXPORT_SYMBOL_GPL(gpiod_to_chip); static int gpiochip_find_base(int ngpio) { struct gpio_device *gdev; - int base = ARCH_NR_GPIOS - ngpio; + int base = GPIO_DYNAMIC_BASE; - list_for_each_entry_reverse(gdev, &gpio_devices, list) { + list_for_each_entry(gdev, &gpio_devices, list) { /* found a free space? */ - if (gdev->base + gdev->ngpio <= base) + if (gdev->base >= base + ngpio) break; - /* nope, check the space right before the chip */ - base = gdev->base - ngpio; + /* nope, check the space right after the chip */ + base = gdev->base + gdev->ngpio; } if (gpio_is_valid(base)) { @@ -366,12 +367,12 @@ static int gpiochip_set_desc_names(struct gpio_chip *gc) static int devprop_gpiochip_set_names(struct gpio_chip *chip) { struct gpio_device *gdev = chip->gpiodev; - struct fwnode_handle *fwnode = dev_fwnode(&gdev->dev); + struct device *dev = &gdev->dev; const char **names; int ret, i; int count; - count = fwnode_property_string_array_count(fwnode, "gpio-line-names"); + count = device_property_string_array_count(dev, "gpio-line-names"); if (count < 0) return 0; @@ -384,7 +385,7 @@ static int devprop_gpiochip_set_names(struct gpio_chip *chip) * gpiochips. */ if (count <= chip->offset) { - dev_warn(&gdev->dev, "gpio-line-names too short (length %d), cannot map names for the gpiochip at offset %u\n", + 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; } @@ -393,10 +394,10 @@ static int devprop_gpiochip_set_names(struct gpio_chip *chip) if (!names) return -ENOMEM; - ret = fwnode_property_read_string_array(fwnode, "gpio-line-names", + ret = device_property_read_string_array(dev, "gpio-line-names", names, count); if (ret < 0) { - dev_warn(&gdev->dev, "failed to read GPIO line names\n"); + dev_warn(dev, "failed to read GPIO line names\n"); kfree(names); return ret; } @@ -445,9 +446,22 @@ static unsigned long *gpiochip_allocate_mask(struct gpio_chip *gc) return p; } +static unsigned int gpiochip_count_reserved_ranges(struct gpio_chip *gc) +{ + struct device *dev = &gc->gpiodev->dev; + int size; + + /* Format is "start, count, ..." */ + size = device_property_count_u32(dev, "gpio-reserved-ranges"); + if (size > 0 && size % 2 == 0) + return size; + + return 0; +} + static int gpiochip_alloc_valid_mask(struct gpio_chip *gc) { - if (!(of_gpio_need_valid_mask(gc) || gc->init_valid_mask)) + if (!(gpiochip_count_reserved_ranges(gc) || gc->init_valid_mask)) return 0; gc->valid_mask = gpiochip_allocate_mask(gc); @@ -457,8 +471,50 @@ static int gpiochip_alloc_valid_mask(struct gpio_chip *gc) return 0; } +static int gpiochip_apply_reserved_ranges(struct gpio_chip *gc) +{ + struct device *dev = &gc->gpiodev->dev; + unsigned int size; + u32 *ranges; + int ret; + + size = gpiochip_count_reserved_ranges(gc); + if (size == 0) + return 0; + + ranges = kmalloc_array(size, sizeof(*ranges), GFP_KERNEL); + if (!ranges) + return -ENOMEM; + + ret = device_property_read_u32_array(dev, "gpio-reserved-ranges", + ranges, size); + if (ret) { + kfree(ranges); + return ret; + } + + while (size) { + u32 count = ranges[--size]; + u32 start = ranges[--size]; + + if (start >= gc->ngpio || start + count > gc->ngpio) + continue; + + bitmap_clear(gc->valid_mask, start, count); + } + + kfree(ranges); + return 0; +} + static int gpiochip_init_valid_mask(struct gpio_chip *gc) { + int ret; + + ret = gpiochip_apply_reserved_ranges(gc); + if (ret) + return ret; + if (gc->init_valid_mask) return gc->init_valid_mask(gc, gc->valid_mask, @@ -493,7 +549,7 @@ EXPORT_SYMBOL_GPL(gpiochip_line_is_valid); static void gpiodevice_release(struct device *dev) { - struct gpio_device *gdev = container_of(dev, struct gpio_device, dev); + struct gpio_device *gdev = to_gpio_device(dev); unsigned long flags; spin_lock_irqsave(&gpio_lock, flags); @@ -627,7 +683,7 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data, * Assign fwnode depending on the result of the previous calls, * if none of them succeed, assign it to the parent's one. */ - gdev->dev.fwnode = dev_fwnode(&gdev->dev) ?: fwnode; + gc->fwnode = gdev->dev.fwnode = dev_fwnode(&gdev->dev) ?: fwnode; gdev->id = ida_alloc(&gpio_ida, GFP_KERNEL); if (gdev->id < 0) { @@ -719,6 +775,9 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data, * 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; @@ -735,6 +794,7 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data, spin_unlock_irqrestore(&gpio_lock, flags); BLOCKING_INIT_NOTIFIER_HEAD(&gdev->notifier); + init_rwsem(&gdev->sem); #ifdef CONFIG_PINCTRL INIT_LIST_HEAD(&gdev->pin_ranges); @@ -875,6 +935,8 @@ void gpiochip_remove(struct gpio_chip *gc) unsigned long flags; unsigned int i; + down_write(&gdev->sem); + /* FIXME: should the legacy sysfs handling be moved to gpio_device? */ gpiochip_sysfs_unregister(gdev); gpiochip_free_hogs(gc); @@ -909,6 +971,7 @@ void gpiochip_remove(struct gpio_chip *gc) * gone. */ gcdev_unregister(gdev); + up_write(&gdev->sem); put_device(&gdev->dev); } EXPORT_SYMBOL_GPL(gpiochip_remove); @@ -3808,62 +3871,88 @@ static int platform_gpio_count(struct device *dev, const char *con_id) return count; } -/** - * fwnode_get_named_gpiod - obtain a GPIO from firmware node - * @fwnode: handle of the firmware node - * @propname: name of the firmware property representing the GPIO - * @index: index of the GPIO to obtain for the consumer - * @dflags: GPIO initialization flags - * @label: label to attach to the requested GPIO - * - * This function can be used for drivers that get their configuration - * from opaque firmware. - * - * The function properly finds the corresponding GPIO using whatever is the - * underlying firmware interface and then makes sure that the GPIO - * descriptor is requested before it is returned to the caller. - * - * Returns: - * On successful request the GPIO pin is configured in accordance with - * provided @dflags. - * - * In case of error an ERR_PTR() is returned. - */ -static struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode, - const char *propname, int index, - enum gpiod_flags dflags, - const char *label) +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) { - unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT; - struct gpio_desc *desc = ERR_PTR(-ENODEV); - int ret; + struct gpio_desc *desc = ERR_PTR(-ENOENT); if (is_of_node(fwnode)) { - desc = gpiod_get_from_of_node(to_of_node(fwnode), - propname, index, - dflags, - label); - return desc; + dev_dbg(consumer, "using DT '%pfw' for '%s' GPIO lookup\n", + fwnode, con_id); + desc = of_find_gpio(to_of_node(fwnode), con_id, idx, lookupflags); } else if (is_acpi_node(fwnode)) { - struct acpi_gpio_info info; + dev_dbg(consumer, "using ACPI '%pfw' for '%s' GPIO lookup\n", + fwnode, con_id); + 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, con_id); + desc = swnode_find_gpio(fwnode, con_id, idx, lookupflags); + } - desc = acpi_node_get_gpiod(fwnode, propname, index, &info); - if (IS_ERR(desc)) - return desc; + return desc; +} - acpi_gpio_update_gpiod_flags(&dflags, &info); - acpi_gpio_update_gpiod_lookup_flags(&lflags, &info); - } else { - return ERR_PTR(-EINVAL); +static 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) +{ + struct gpio_desc *desc = ERR_PTR(-ENOENT); + unsigned long lookupflags; + int ret; + + if (!IS_ERR_OR_NULL(fwnode)) + desc = gpiod_find_by_fwnode(fwnode, consumer, con_id, idx, + &flags, &lookupflags); + + if (gpiod_not_found(desc) && platform_lookup_allowed) { + /* + * Either we are not using DT or ACPI, or their lookup did not + * return a result. In that case, use platform lookup as a + * fallback. + */ + dev_dbg(consumer, "using lookup tables for GPIO lookup\n"); + desc = gpiod_find(consumer, con_id, idx, &lookupflags); } - /* Currently only ACPI takes this path */ + if (IS_ERR(desc)) { + dev_dbg(consumer, "No GPIO consumer %s found\n", con_id); + return desc; + } + + /* + * If a connection label was passed use that, else attempt to use + * the device name as label + */ ret = gpiod_request(desc, label); - if (ret) - return ERR_PTR(ret); + 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 is a bit of a hack. + * This is necessary to support fixed regulators. + * + * FIXME: Make this more sane and safe. + */ + dev_info(consumer, + "nonexclusive access to GPIO for %s\n", con_id); + return desc; + } - ret = gpiod_configure_flags(desc, propname, lflags, dflags); + ret = gpiod_configure_flags(desc, con_id, lookupflags, flags); if (ret < 0) { + dev_dbg(consumer, "setup of GPIO %s failed\n", con_id); gpiod_put(desc); return ERR_PTR(ret); } @@ -3896,29 +3985,12 @@ static struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode, * 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, + const char *con_id, + int index, enum gpiod_flags flags, const char *label) { - struct gpio_desc *desc; - char prop_name[32]; /* 32 is max size of property name */ - unsigned int i; - - for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) { - if (con_id) - snprintf(prop_name, sizeof(prop_name), "%s-%s", - con_id, gpio_suffixes[i]); - else - snprintf(prop_name, sizeof(prop_name), "%s", - gpio_suffixes[i]); - - desc = fwnode_get_named_gpiod(fwnode, prop_name, index, flags, - label); - if (!gpiod_not_found(desc)) - break; - } - - return desc; + return gpiod_find_and_request(NULL, fwnode, con_id, index, flags, label, false); } EXPORT_SYMBOL_GPL(fwnode_gpiod_get_index); @@ -3937,6 +4009,8 @@ int gpiod_count(struct device *dev, const char *con_id) count = of_gpio_get_count(dev, con_id); else if (is_acpi_node(fwnode)) count = acpi_gpio_count(dev, 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); @@ -4072,70 +4146,11 @@ struct gpio_desc *__must_check gpiod_get_index(struct device *dev, unsigned int idx, enum gpiod_flags flags) { - unsigned long lookupflags = GPIO_LOOKUP_FLAGS_DEFAULT; - struct gpio_desc *desc = NULL; - int ret; - /* Maybe we have a device name, maybe not */ + struct fwnode_handle *fwnode = dev ? dev_fwnode(dev) : NULL; const char *devname = dev ? dev_name(dev) : "?"; - const struct fwnode_handle *fwnode = dev ? dev_fwnode(dev) : NULL; - - dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id); - - /* Using device tree? */ - if (is_of_node(fwnode)) { - dev_dbg(dev, "using device tree for GPIO lookup\n"); - desc = of_find_gpio(dev, con_id, idx, &lookupflags); - } else if (is_acpi_node(fwnode)) { - dev_dbg(dev, "using ACPI for GPIO lookup\n"); - desc = acpi_find_gpio(dev, con_id, idx, &flags, &lookupflags); - } - - /* - * Either we are not using DT or ACPI, or their lookup did not return - * a result. In that case, use platform lookup as a fallback. - */ - if (!desc || gpiod_not_found(desc)) { - dev_dbg(dev, "using lookup tables for GPIO lookup\n"); - desc = gpiod_find(dev, con_id, idx, &lookupflags); - } - - if (IS_ERR(desc)) { - dev_dbg(dev, "No GPIO consumer %s found\n", con_id); - return desc; - } - - /* - * If a connection label was passed use that, else attempt to use - * the device name as label - */ - ret = gpiod_request(desc, con_id ?: devname); - 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 is a bit of a hack. - * This is necessary to support fixed regulators. - * - * FIXME: Make this more sane and safe. - */ - dev_info(dev, "nonexclusive access to GPIO for %s\n", con_id ?: devname); - return desc; - } - - ret = gpiod_configure_flags(desc, con_id, lookupflags, flags); - if (ret < 0) { - dev_dbg(dev, "setup of GPIO %s failed\n", con_id); - gpiod_put(desc); - return ERR_PTR(ret); - } + const char *label = con_id ?: devname; - blocking_notifier_call_chain(&desc->gdev->notifier, - GPIOLINE_CHANGED_REQUESTED, desc); - - return desc; + return gpiod_find_and_request(dev, fwnode, con_id, idx, flags, label, true); } EXPORT_SYMBOL_GPL(gpiod_get_index); |