diff options
| author | Bartosz Golaszewski <bartosz.golaszewski@linaro.org> | 2024-01-24 17:02:03 +0100 |
|---|---|---|
| committer | Bartosz Golaszewski <bartosz.golaszewski@linaro.org> | 2024-02-12 11:00:55 +0100 |
| commit | f067372c6a3c3b0c5cc775157408970b8fa6c010 (patch) | |
| tree | 0d3d05240412387176e1ba2c426e46726ab380bb /drivers/gpio | |
| parent | gpio: protect the pointer to gpio_chip in gpio_device with SRCU (diff) | |
| download | linux-f067372c6a3c3b0c5cc775157408970b8fa6c010.tar.xz linux-f067372c6a3c3b0c5cc775157408970b8fa6c010.zip | |
gpio: remove the RW semaphore from the GPIO device
With all accesses to gdev->chip being protected with SRCU, we can now
remove the RW-semaphore specific to the character device which
fulfilled the same role up to this point.
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Diffstat (limited to 'drivers/gpio')
| -rw-r--r-- | drivers/gpio/gpiolib.c | 4 | ||||
| -rw-r--r-- | drivers/gpio/gpiolib.h | 5 |
2 files changed, 0 insertions, 9 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 1a9d045b5a6b..875b40376c0b 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -963,7 +963,6 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data, BLOCKING_INIT_NOTIFIER_HEAD(&gdev->line_state_notifier); BLOCKING_INIT_NOTIFIER_HEAD(&gdev->device_notifier); - init_rwsem(&gdev->sem); ret = init_srcu_struct(&gdev->srcu); if (ret) @@ -1102,8 +1101,6 @@ void gpiochip_remove(struct gpio_chip *gc) struct gpio_device *gdev = gc->gpiodev; 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); @@ -1142,7 +1139,6 @@ void gpiochip_remove(struct gpio_chip *gc) * gone. */ gcdev_unregister(gdev); - up_write(&gdev->sem); gpio_device_put(gdev); } EXPORT_SYMBOL_GPL(gpiochip_remove); diff --git a/drivers/gpio/gpiolib.h b/drivers/gpio/gpiolib.h index b3810f7d286a..07443d26cbca 100644 --- a/drivers/gpio/gpiolib.h +++ b/drivers/gpio/gpiolib.h @@ -16,7 +16,6 @@ #include <linux/gpio/driver.h> #include <linux/module.h> #include <linux/notifier.h> -#include <linux/rwsem.h> #include <linux/srcu.h> #define GPIOCHIP_NAME "gpiochip" @@ -46,9 +45,6 @@ * requested, released or reconfigured * @device_notifier: used to notify character device wait queues about the GPIO * device being unregistered - * @sem: protects the structure from a NULL-pointer dereference of @chip by - * user-space operations when the device gets unregistered during - * a hot-unplug event * @srcu: protects the pointer to the underlying GPIO chip * @pin_ranges: range of pins served by the GPIO driver * @@ -73,7 +69,6 @@ struct gpio_device { struct list_head list; struct blocking_notifier_head line_state_notifier; struct blocking_notifier_head device_notifier; - struct rw_semaphore sem; struct srcu_struct srcu; #ifdef CONFIG_PINCTRL |