gpio: Respect valid_mask when requesting GPIOs

When GPIOs were requested the validity of GPIOs were checked only when
the GPIO-chip had the request -callback populated. This made using
masked GPIOs possible.

The GPIO chip driver authors may find it difficult to understand the
relation of enforsing the GPIO validity and the 'request' -callback
because the current documentation for the 'request' callback does not
mention this. It only states:

 * @request: optional hook for chip-specific activation, such as
 *      enabling module power and clock; may sleep

The validity of the GPIO line should be checked whether the driver
provides the 'request' callback or not.

Unconditionally check the GPIO validity when GPIO is being requested.

Signed-off-by: Matti Vaittinen <mazziesaccount@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/cd5e067b80e1bb590027bc3bfa817e7f794f21c3.1741180097.git.mazziesaccount@gmail.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 8724c7d8459e9073882e323bba0dad4c72703882..b5f472beb3bd8ade0e57bcff30dbaae3a503ff9b 100644 (file)
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -2358,16 +2358,16 @@ static int gpiod_request_commit(struct gpio_desc *desc, const char *label)
        if (test_and_set_bit(FLAG_REQUESTED, &desc->flags))
                return -EBUSY;
 
+       offset = gpio_chip_hwgpio(desc);
+       if (!gpiochip_line_is_valid(guard.gc, offset))
+               return -EINVAL;
+
        /* NOTE:  gpio_request() can be called in early boot,
         * before IRQs are enabled, for non-sleeping (SOC) GPIOs.
         */
 
        if (guard.gc->request) {
-               offset = gpio_chip_hwgpio(desc);
-               if (gpiochip_line_is_valid(guard.gc, offset))
-                       ret = guard.gc->request(guard.gc, offset);
-               else
-                       ret = -EINVAL;
+               ret = guard.gc->request(guard.gc, offset);
                if (ret > 0)
                        ret = -EBADE;
                if (ret)