[PATCH] gpiolib: Defer failed gpio requests by default

[Mark Brown]

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@xxxxxxxxxxxxxxxxxxxxxxxxxxx>
---
 drivers/gpio/gpiolib.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 566d012..b244b0c 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -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);
-- 
1.7.10

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/