Commit 30e0fd3c authored by Hugo Villeneuve's avatar Hugo Villeneuve Committed by Bartosz Golaszewski
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gpiolib: fix performance regression when using gpio_chip_get_multiple() 



commit 74abd086 ("gpiolib: sanitize the return value of
gpio_chip::get_multiple()") altered the value returned by
gc->get_multiple() in case it is positive (> 0), but failed to return
for other cases (<= 0).

This may result in the "if (gc->get)" block being executed and thus
negates the performance gain that is normally obtained by using
gc->get_multiple().

Fix by returning the result of gc->get_multiple() if it is <= 0.

Also move the "ret" variable to the scope where it is used, which as an
added bonus fixes an indentation error introduced by the aforementioned
commit.

Fixes: 74abd086 ("gpiolib: sanitize the return value of gpio_chip::get_multiple()")
Cc: stable@vger.kernel.org
Signed-off-by: default avatarHugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20250703191829.2952986-1-hugo@hugovil.com


Signed-off-by: default avatarBartosz Golaszewski <bartosz.golaszewski@linaro.org>
parent d0b3b7b2

drivers/gpio/gpiolib.c

+3 −2
Original line number Diff line number Diff line
@@ -3297,14 +3297,15 @@ static int gpiod_get_raw_value_commit(const struct gpio_desc *desc) 
static int gpio_chip_get_multiple(struct gpio_chip *gc,

				  unsigned long *mask, unsigned long *bits)

{

	int ret;

	

	lockdep_assert_held(&gc->gpiodev->srcu);



	if (gc->get_multiple) {

		int ret;



		ret = gc->get_multiple(gc, mask, bits);

		if (ret > 0)

			return -EBADE;

		return ret;

	}



	if (gc->get) {