gpio: return -ENOTSUPP if debounce cannot be set

It appears some drivers are using gpio_set_debounce()
opportunistically, i.e. without knowing whether it works or
not. (Example: input/keyboard/gpio_keys.c) to account for
this use case, return -ENOTSUPP and do not print any
warnings in this case.

Took a round over the other gpio_set_debounce() consumers
to make sure that none of them are relying on the returned
error code to be something specific.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This commit is contained in:
Linus Walleij 2013-09-04 14:17:08 +02:00
parent be1a4b1308
commit 65d876564e

View file

@ -1763,6 +1763,9 @@ EXPORT_SYMBOL_GPL(gpio_direction_output);
* gpio_set_debounce - sets @debounce time for a @gpio
* @gpio: the gpio to set debounce time
* @debounce: debounce time is microseconds
*
* returns -ENOTSUPP if the controller does not support setting
* debounce.
*/
static int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce)
{
@ -1778,9 +1781,9 @@ static int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce)
chip = desc->chip;
if (!chip->set || !chip->set_debounce) {
pr_warn("%s: missing set() or set_debounce() operations\n",
pr_debug("%s: missing set() or set_debounce() operations\n",
__func__);
return -EIO;
return -ENOTSUPP;
}
spin_lock_irqsave(&gpio_lock, flags);