[PATCH] extcon: gpio: Request gpio pin before modifying its state

From: Guenter Roeck
Date: Fri Nov 22 2013 - 12:26:21 EST


Commit 338de0ca (extcon: gpio: Use gpio driver/chip debounce if supported)
introduced a call to gpio_set_debounce() before actually requesting the
respective gpio pin from the gpio subsystem.

The gpio subsystem expects that a gpio pin was requested before modifying its
state. Not doing so results in a warning from gpiolib, and the gpio pin is
auto-requested. This in turn causes the subsequent devm_gpio_request_one()
to fail. So devm_gpio_request_one() must be called prior to calling
gpio_set_debounce().

Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
---
drivers/extcon/extcon-gpio.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/extcon/extcon-gpio.c b/drivers/extcon/extcon-gpio.c
index 7e0dff5..4736a9c 100644
--- a/drivers/extcon/extcon-gpio.c
+++ b/drivers/extcon/extcon-gpio.c
@@ -105,6 +105,12 @@ static int gpio_extcon_probe(struct platform_device *pdev)
extcon_data->state_off = pdata->state_off;
if (pdata->state_on && pdata->state_off)
extcon_data->edev.print_state = extcon_gpio_print_state;
+
+ ret = devm_gpio_request_one(&pdev->dev, extcon_data->gpio, GPIOF_DIR_IN,
+ pdev->name);
+ if (ret < 0)
+ return ret;
+
if (pdata->debounce) {
ret = gpio_set_debounce(extcon_data->gpio,
pdata->debounce * 1000);
@@ -117,11 +123,6 @@ static int gpio_extcon_probe(struct platform_device *pdev)
if (ret < 0)
return ret;

- ret = devm_gpio_request_one(&pdev->dev, extcon_data->gpio, GPIOF_DIR_IN,
- pdev->name);
- if (ret < 0)
- goto err;
-
INIT_DELAYED_WORK(&extcon_data->work, gpio_extcon_work);

extcon_data->irq = gpio_to_irq(extcon_data->gpio);
--
1.7.9.7

--
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/