* Roger Quadros <rog...@ti.com> [131204 03:35]:
> 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.
Uh, OK, sorry that was an unexpected side effect. We still should keep the
return values though instead of just ignoring them.
> 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);
This looks OK to me.
> @@ -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;
>
Can't you just have:
int ret = 0;
> 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;
> }
Then the rest of this change is not needed and we check the return value for
twl4030_set_gpio_direction. Makes sense to keep the comment there though.
Regards,
Tony
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