gpio: sysfs: correct error handling on 'value' attribute read.
'value' attribute is supposed to only return 0 or 1 according to
the documentation.
With today's implementation, if gpiod_get_value_cansleep() fails
the printed 'value' is a negative value.
This patch ensures that an error is returned on read instead.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/gpio/gpiolib-sysfs.c b/drivers/gpio/gpiolib-sysfs.c
index 3b2465b..ef34b8f 100644
--- a/drivers/gpio/gpiolib-sysfs.c
+++ b/drivers/gpio/gpiolib-sysfs.c
@@ -106,8 +106,12 @@ static ssize_t value_show(struct device *dev,
mutex_lock(&data->mutex);
- status = sprintf(buf, "%d\n", gpiod_get_value_cansleep(desc));
+ status = gpiod_get_value_cansleep(desc);
+ if (status < 0)
+ goto err;
+ status = sprintf(buf, "%d\n", status);
+err:
mutex_unlock(&data->mutex);
return status;