[PATCH 1/1] gpio: twl4030: Fix regression for twl gpio LED output

Roger Quadros rogerq at ti.com
Wed Dec 4 06:34:31 EST 2013


Commit 0b2aa8be introduced a regression that causes failure
in setting LED GPO direction to OUT.

This causes USB host probe failures for Beagleboard C4.

[    2.075469] platform usb_phy_gen_xceiv.2: Driver usb_phy_gen_xceiv requests probe deferral
[    2.090454] hsusb2_vcc: Failed to request enable GPIO510: -22
[    2.100982] reg-fixed-voltage reg-fixed-voltage.0.auto: Failed to register regulator: -22
[    2.109954] reg-fixed-voltage: probe of reg-fixed-voltage.0.auto failed with error -22

direction_out/direction_in must return 0 if the operation succeeded.

Signed-off-by: Roger Quadros <rogerq at ti.com>
---
 drivers/gpio/gpio-twl4030.c | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/drivers/gpio/gpio-twl4030.c b/drivers/gpio/gpio-twl4030.c
index b97d6a6..0999ed1 100644
--- a/drivers/gpio/gpio-twl4030.c
+++ b/drivers/gpio/gpio-twl4030.c
@@ -294,13 +294,13 @@ out:
 static int twl_direction_in(struct gpio_chip *chip, unsigned offset)
 {
 	struct gpio_twl4030_priv *priv = to_gpio_twl4030(chip);
-	int ret;
+	int ret = 0;
 
 	mutex_lock(&priv->mutex);
 	if (offset < TWL4030_GPIO_MAX)
-		ret = twl4030_set_gpio_direction(offset, 1);
+		twl4030_set_gpio_direction(offset, 1);
 	else
-		ret = -EINVAL;
+		ret = -EINVAL;	/* LED outputs can't be set as input */
 
 	if (!ret)
 		priv->direction &= ~BIT(offset);
@@ -354,18 +354,21 @@ static void twl_set(struct gpio_chip *chip, unsigned offset, int value)
 static int twl_direction_out(struct gpio_chip *chip, unsigned offset, int value)
 {
 	struct gpio_twl4030_priv *priv = to_gpio_twl4030(chip);
-	int ret = -EINVAL;
 
 	mutex_lock(&priv->mutex);
 	if (offset < TWL4030_GPIO_MAX)
-		ret = twl4030_set_gpio_direction(offset, 0);
+		twl4030_set_gpio_direction(offset, 0);
+
+	/*
+	 *  LED gpio's i.e. offset >= TWL4030_GPIO_MAX are always output
+	 */
 
 	priv->direction |= BIT(offset);
 	mutex_unlock(&priv->mutex);
 
 	twl_set(chip, offset, value);
 
-	return ret;
+	return 0;
 }
 
 static int twl_to_irq(struct gpio_chip *chip, unsigned offset)
-- 
1.8.3.2




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