On 12/04/2013 07:37 PM, Tony Lindgren wrote:
> * 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.
OK.
>
>> 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;
Yes, i'll add that.
>
>> 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.
OK. Will post v2.
cheers,
-roger
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