Commit 6c82e737 authored by Bartosz Golaszewski's avatar Bartosz Golaszewski
Browse files

gpio: reduce the functionality of validate_desc() 



Checking desc->gdev->chip for NULL without holding it in place with some
serializing mechanism is pointless. Remove this check. Also don't check
desc->gdev for NULL as it can never happen. We'll be protecting
gdev->chip with SRCU soon but we will provide a dedicated, automatic
class for that.

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 7fe595b3

drivers/gpio/gpiolib.c

+3 −15
Original line number Diff line number Diff line
@@ -2257,19 +2257,12 @@ static int validate_desc(const struct gpio_desc *desc, const char *func) 
{

	if (!desc)

		return 0;



	if (IS_ERR(desc)) {

		pr_warn("%s: invalid GPIO (errorpointer)\n", func);

		return PTR_ERR(desc);

	}

	if (!desc->gdev) {

		pr_warn("%s: invalid GPIO (no device)\n", func);

		return -EINVAL;

	}

	if (!desc->gdev->chip) {

		dev_warn(&desc->gdev->dev,

			 "%s: backing chip is gone\n", func);

		return 0;

	}



	return 1;

}
@@ -2345,12 +2338,7 @@ static bool gpiod_free_commit(struct gpio_desc *desc) 


void gpiod_free(struct gpio_desc *desc)

{

	/*

	 * We must not use VALIDATE_DESC_VOID() as the underlying gdev->chip

	 * may already be NULL but we still want to put the references.

	 */

	if (!desc)

		return;

	VALIDATE_DESC_VOID(desc);



	if (!gpiod_free_commit(desc))

		WARN_ON(1);