From: Bartosz Golaszewski Date: Mon, 9 Mar 2026 12:42:41 +0000 (+0100) Subject: gpio: remove machine hogs X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=dea046e7f46f2357124a465e058c92cac3e351c5;p=thirdparty%2Fkernel%2Flinux.git gpio: remove machine hogs With no more users, remove legacy machine hog API from the kernel. Reviewed-by: Linus Walleij Reviewed-by: Andy Shevchenko Link: https://patch.msgid.link/20260309-gpio-hog-fwnode-v2-5-4e61f3dbf06a@oss.qualcomm.com Signed-off-by: Bartosz Golaszewski --- diff --git a/Documentation/driver-api/gpio/board.rst b/Documentation/driver-api/gpio/board.rst index 069b54d8591bd..0993cac891fb5 100644 --- a/Documentation/driver-api/gpio/board.rst +++ b/Documentation/driver-api/gpio/board.rst @@ -239,22 +239,6 @@ mapping and is thus transparent to GPIO consumers. A set of functions such as gpiod_set_value() is available to work with the new descriptor-oriented interface. -Boards using platform data can also hog GPIO lines by defining GPIO hog tables. - -.. code-block:: c - - struct gpiod_hog gpio_hog_table[] = { - GPIO_HOG("gpio.0", 10, "foo", GPIO_ACTIVE_LOW, GPIOD_OUT_HIGH), - { } - }; - -And the table can be added to the board code as follows:: - - gpiod_add_hogs(gpio_hog_table); - -The line will be hogged as soon as the gpiochip is created or - in case the -chip was created earlier - when the hog table is registered. - Arrays of pins -------------- In addition to requesting pins belonging to a function one by one, a device may diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 4a57d98826006..56fda7891d554 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -103,9 +103,6 @@ static DEFINE_MUTEX(gpio_devices_lock); /* Ensures coherence during read-only accesses to the list of GPIO devices. */ DEFINE_STATIC_SRCU(gpio_devices_srcu); -static DEFINE_MUTEX(gpio_machine_hogs_mutex); -static LIST_HEAD(gpio_machine_hogs); - const char *const gpio_suffixes[] = { "gpios", "gpio", NULL }; static void gpiochip_free_hogs(struct gpio_chip *gc); @@ -930,36 +927,6 @@ err_remove_device: return ret; } -static void gpiochip_machine_hog(struct gpio_chip *gc, struct gpiod_hog *hog) -{ - 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; - } - - 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 void gpiochip_machine_hog_lines(struct gpio_chip *gc) -{ - struct gpiod_hog *hog; - - guard(mutex)(&gpio_machine_hogs_mutex); - - list_for_each_entry(hog, &gpio_machine_hogs, list) { - if (!strcmp(gc->label, hog->chip_label)) - gpiochip_machine_hog(gc, hog); - } -} - int gpiochip_add_hog(struct gpio_chip *gc, struct fwnode_handle *fwnode) { struct fwnode_handle *gc_node = dev_fwnode(&gc->gpiodev->dev); @@ -1047,8 +1014,6 @@ static int gpiochip_hog_lines(struct gpio_chip *gc) return ret; } - gpiochip_machine_hog_lines(gc); - return 0; } @@ -4578,42 +4543,6 @@ void gpiod_remove_lookup_table(struct gpiod_lookup_table *table) } 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 bool gpiod_match_lookup_table(struct device *dev, const struct gpiod_lookup_table *table) { diff --git a/include/linux/gpio/machine.h b/include/linux/gpio/machine.h index 44e5f162973eb..5eb88f5d0630f 100644 --- a/include/linux/gpio/machine.h +++ b/include/linux/gpio/machine.h @@ -46,23 +46,6 @@ struct gpiod_lookup_table { struct gpiod_lookup table[]; }; -/** - * struct gpiod_hog - GPIO line hog table - * @chip_label: name of the chip the GPIO belongs to - * @chip_hwnum: hardware number (i.e. relative to the chip) of the GPIO - * @line_name: consumer name for the hogged line - * @lflags: bitmask of gpio_lookup_flags GPIO_* values - * @dflags: GPIO flags used to specify the direction and value - */ -struct gpiod_hog { - struct list_head list; - const char *chip_label; - u16 chip_hwnum; - const char *line_name; - unsigned long lflags; - int dflags; -}; - /* * Helper for lookup tables with just one single lookup for a device. */ @@ -95,24 +78,10 @@ static struct gpiod_lookup_table _name = { \ .flags = _flags, \ } -/* - * Simple definition of a single GPIO hog in an array. - */ -#define GPIO_HOG(_chip_label, _chip_hwnum, _line_name, _lflags, _dflags) \ -(struct gpiod_hog) { \ - .chip_label = _chip_label, \ - .chip_hwnum = _chip_hwnum, \ - .line_name = _line_name, \ - .lflags = _lflags, \ - .dflags = _dflags, \ -} - #ifdef CONFIG_GPIOLIB void gpiod_add_lookup_table(struct gpiod_lookup_table *table); void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n); void gpiod_remove_lookup_table(struct gpiod_lookup_table *table); -void gpiod_add_hogs(struct gpiod_hog *hogs); -void gpiod_remove_hogs(struct gpiod_hog *hogs); #else /* ! CONFIG_GPIOLIB */ static inline void gpiod_add_lookup_table(struct gpiod_lookup_table *table) {} @@ -120,8 +89,6 @@ static inline void gpiod_add_lookup_tables(struct gpiod_lookup_table **tables, size_t n) {} static inline void gpiod_remove_lookup_table(struct gpiod_lookup_table *table) {} -static inline void gpiod_add_hogs(struct gpiod_hog *hogs) {} -static inline void gpiod_remove_hogs(struct gpiod_hog *hogs) {} #endif /* CONFIG_GPIOLIB */ #endif /* __LINUX_GPIO_MACHINE_H */