[PATCH v2 1/1] gpio: twl4030: Fix regression for twl gpio LED output

[Tony Lindgren]

* Roger Quadros <rogerq at ti.com> [131205 01:24]:
> 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.
> 
> Also, don't update direction flag and output data if twl4030_set_gpio_direction()
> failed inside twl_direction_out();
> 
> Signed-off-by: Roger Quadros <rogerq at ti.com>

Acked-by: Tony Lindgren <tony at atomide.com>

Linus, commit 0b2aa8be is in mainline now, so feel free to pick this one
up if it looks OK to you. This should be also Cc stable as 0b2aa8be has
that.

Regards,

Tony

> ---
>  drivers/gpio/gpio-twl4030.c | 15 ++++++++++++---
>  1 file changed, 12 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/gpio/gpio-twl4030.c b/drivers/gpio/gpio-twl4030.c
> index b97d6a6..f999689 100644
> --- a/drivers/gpio/gpio-twl4030.c
> +++ b/drivers/gpio/gpio-twl4030.c
> @@ -300,7 +300,7 @@ static int twl_direction_in(struct gpio_chip *chip, unsigned offset)
>  	if (offset < TWL4030_GPIO_MAX)
>  		ret = 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);
> @@ -354,11 +354,20 @@ 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;
> +	int ret = 0;
>  
>  	mutex_lock(&priv->mutex);
> -	if (offset < TWL4030_GPIO_MAX)
> +	if (offset < TWL4030_GPIO_MAX) {
>  		ret = twl4030_set_gpio_direction(offset, 0);
> +		if (ret) {
> +			mutex_unlock(&priv->mutex);
> +			return ret;
> +		}
> +	}
> +
> +	/*
> +	 *  LED gpios i.e. offset >= TWL4030_GPIO_MAX are always output
> +	 */
>  
>  	priv->direction |= BIT(offset);
>  	mutex_unlock(&priv->mutex);
> -- 
> 1.8.3.2
>