Commit e9354576 authored Jul 09, 2012 by Mark Brown Committed by Linus Walleij Jul 17, 2012

gpiolib: Defer failed gpio requests by default

Since users must be explicitly provided with a GPIO number in order to
request one the overwhelmingly common case for failing to request will
be that the required GPIO driver has not yet registered and we should
therefore defer until it has registered.

In order to avoid having to code this logic in individual drivers have
gpio_request() return -EPROBE_DEFER when failing to look up the GPIO.
Drivers which don't want this behaviour can override it if they desire.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

parent 6d994710

drivers/gpio/gpiolib.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -1186,7 +1186,7 @@ int gpio_request(unsigned gpio, const char *label)
		{
		struct gpio_desc *desc;
		struct gpio_chip *chip;
		int status = -EINVAL;
		int status = -EPROBE_DEFER;
		unsigned long flags;

		spin_lock_irqsave(&gpio_lock, flags);

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