Messages in this thread |  | | Date | Wed, 4 Dec 2013 09:37:05 -0800 | From | Tony Lindgren <> | Subject | Re: [PATCH 1/1] gpio: twl4030: Fix regression for twl gpio LED output |
| |
* Roger Quadros <rogerq@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
|  |