gpio: remove machine hogs

With no more users, remove legacy machine hog API from the kernel.

Reviewed-by: Linus Walleij <linusw@kernel.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://patch.msgid.link/20260309-gpio-hog-fwnode-v2-5-4e61f3dbf06a@oss.qualcomm.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>

diff --git a/Documentation/driver-api/gpio/board.rst b/Documentation/driver-api/gpio/board.rst
index 069b54d8591bdeb975a6c650d643db4f7eb98ab7..0993cac891fb5e4887a1aee6deae273197c6aae1 100644 (file)
--- 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 4a57d98826006484091b85286880c5d85e606321..56fda7891d5546ef423513e419f8a673ddcef72c 100644 (file)
--- 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 44e5f162973eb6f6e85188f56ec34e1e3e2beab6..5eb88f5d0630f83b6a3a0e6727103c319e139b27 100644 (file)
--- 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 */