Commit 8a5b477b authored by Bartosz Golaszewski's avatar Bartosz Golaszewski
Browse files

gpio: add the can_sleep flag to struct gpio_device 



Duplicating the can_sleep value in GPIO device will allow us to not
needlessly dereference the chip pointer in several places and reduce the
number of SRCU read-only critical sections.

Signed-off-by: default avatarBartosz Golaszewski <bartosz.golaszewski@linaro.org>
Reviewed-by: default avatarLinus Walleij <linus.walleij@linaro.org>
Acked-by: default avatarAndy Shevchenko <andriy.shevchenko@linux.intel.com>
parent c5cf334d

drivers/gpio/gpiolib.c

+6 −5
Original line number Diff line number Diff line
@@ -901,6 +901,7 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data, 
	}



	gdev->ngpio = gc->ngpio;

	gdev->can_sleep = gc->can_sleep;



	scoped_guard(mutex, &gpio_devices_lock) {

		/*
@@ -3072,7 +3073,7 @@ int gpiod_get_raw_value(const struct gpio_desc *desc) 
{

	VALIDATE_DESC(desc);

	/* Should be using gpiod_get_raw_value_cansleep() */

	WARN_ON(desc->gdev->chip->can_sleep);

	WARN_ON(desc->gdev->can_sleep);

	return gpiod_get_raw_value_commit(desc);

}

EXPORT_SYMBOL_GPL(gpiod_get_raw_value);
@@ -3093,7 +3094,7 @@ int gpiod_get_value(const struct gpio_desc *desc) 


	VALIDATE_DESC(desc);

	/* Should be using gpiod_get_value_cansleep() */

	WARN_ON(desc->gdev->chip->can_sleep);

	WARN_ON(desc->gdev->can_sleep);



	value = gpiod_get_raw_value_commit(desc);

	if (value < 0)
@@ -3366,7 +3367,7 @@ void gpiod_set_raw_value(struct gpio_desc *desc, int value) 
{

	VALIDATE_DESC_VOID(desc);

	/* Should be using gpiod_set_raw_value_cansleep() */

	WARN_ON(desc->gdev->chip->can_sleep);

	WARN_ON(desc->gdev->can_sleep);

	gpiod_set_raw_value_commit(desc, value);

}

EXPORT_SYMBOL_GPL(gpiod_set_raw_value);
@@ -3407,7 +3408,7 @@ void gpiod_set_value(struct gpio_desc *desc, int value) 
{

	VALIDATE_DESC_VOID(desc);

	/* Should be using gpiod_set_value_cansleep() */

	WARN_ON(desc->gdev->chip->can_sleep);

	WARN_ON(desc->gdev->can_sleep);

	gpiod_set_value_nocheck(desc, value);

}

EXPORT_SYMBOL_GPL(gpiod_set_value);
@@ -3471,7 +3472,7 @@ EXPORT_SYMBOL_GPL(gpiod_set_array_value); 
int gpiod_cansleep(const struct gpio_desc *desc)

{

	VALIDATE_DESC(desc);

	return desc->gdev->chip->can_sleep;

	return desc->gdev->can_sleep;

}

EXPORT_SYMBOL_GPL(gpiod_cansleep);

drivers/gpio/gpiolib.h

+3 −0
Original line number Diff line number Diff line
@@ -34,6 +34,8 @@ 
 * @descs: array of ngpio descriptors.

 * @ngpio: the number of GPIO lines on this GPIO device, equal to the size

 * of the @descs array.

 * @can_sleep: indicate whether the GPIO chip driver's callbacks can sleep

 * implying that they cannot be used from atomic context

 * @base: GPIO base in the DEPRECATED global Linux GPIO numberspace, assigned

 * at device creation time.

 * @label: a descriptive name for the GPIO device, such as the part number
@@ -64,6 +66,7 @@ struct gpio_device { 
	struct gpio_desc	*descs;

	int			base;

	u16			ngpio;

	bool			can_sleep;

	const char		*label;

	void			*data;

	struct list_head        list;