gpiolib: provide gpiod_remove_hogs()

Currently all users of gpiod_add_hogs() call it only once at system
init so there never was any need for a mechanism allowing to remove
them. Now the upcoming gpio-sim will need to tear down chips with hogged
lines so provide a function that allows to remove hogs.

Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
This commit is contained in:
Bartosz Golaszewski 2021-12-07 10:34:06 +01:00
parent ab39d6988d
commit dd61b29207
2 changed files with 13 additions and 0 deletions

View file

@ -3557,6 +3557,17 @@ void gpiod_add_hogs(struct gpiod_hog *hogs)
}
EXPORT_SYMBOL_GPL(gpiod_add_hogs);
void gpiod_remove_hogs(struct gpiod_hog *hogs)
{
struct gpiod_hog *hog;
mutex_lock(&gpio_machine_hogs_mutex);
for (hog = &hogs[0]; hog->chip_label; hog++)
list_del(&hog->list);
mutex_unlock(&gpio_machine_hogs_mutex);
}
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;

View file

@ -100,6 +100,7 @@ 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) {}
@ -108,6 +109,7 @@ 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 */