[PATCH 3/3] gpiolib: don't double-check the gc->get callback's existence

[Bartosz Golaszewski]

From: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>

gpiochip_get() is called only in two places: in gpio_chip_get_value()
and in gpiochip_get_multiple() where the existence of the gc->get()
callback is already checked. It makes sense to unduplicate the check by
moving it one level up the stack.

Fixes: 86ef402d805d ("gpiolib: sanitize the return value of gpio_chip::get()")
Suggested-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxx>
Closes: https://lore.kernel.org/all/Z7yekJ8uRh8dphKn@xxxxxxxxxxxxxxxxxx/
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
---
 drivers/gpio/gpiolib.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index d076b2ec633f..b8f10192f27e 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -3158,9 +3158,7 @@ static int gpiochip_get(struct gpio_chip *gc, unsigned int offset)
 
 	lockdep_assert_held(&gc->gpiodev->srcu);
 
-	if (!gc->get)
-		return -EIO;
-
+	/* Make sure this is called after checking for gc->get(). */
 	ret = gc->get(gc, offset);
 	if (ret > 1)
 		ret = -EBADE;
@@ -3170,7 +3168,7 @@ static int gpiochip_get(struct gpio_chip *gc, unsigned int offset)
 
 static int gpio_chip_get_value(struct gpio_chip *gc, const struct gpio_desc *desc)
 {
-	return gpiochip_get(gc, gpio_chip_hwgpio(desc));
+	return gc->get ? gpiochip_get(gc, gpio_chip_hwgpio(desc)) : -EIO;
 }
 
 /* I/O calls are only valid after configuration completed; the relevant

-- 
2.45.2