From: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Date: Thu, 3 Jul 2025 19:18:29 +0000 (-0400)
Subject: gpiolib: fix performance regression when using gpio_chip_get_multiple()
X-Git-Tag: v6.16-rc6~15^2~2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=30e0fd3c0273dc106320081793793a424f1f1950;p=thirdparty%2Fkernel%2Flinux.git

gpiolib: fix performance regression when using gpio_chip_get_multiple()

commit 74abd086d2ee ("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: 74abd086d2ee ("gpiolib: sanitize the return value of gpio_chip::get_multiple()")
Cc: stable@vger.kernel.org
Signed-off-by: Hugo Villeneuve <hvilleneuve@dimonoff.com>
Link: https://lore.kernel.org/r/20250703191829.2952986-1-hugo@hugovil.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
---

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index fdafa0df1b432..3a3eca5b4c40b 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -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) {