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| author | Tony Lindgren <tony@atomide.com> | 2013-11-18 15:22:49 -0800 |
|---|---|---|
| committer | Tony Lindgren <tony@atomide.com> | 2013-11-18 15:22:59 -0800 |
| commit | 0b2aa8bed3e13892fcac77e4f50ec6e80125469d (patch) | |
| tree | 8f4e0b5713b014bf33d350d407bb7181b5745616 /drivers/gpio | |
| parent | cae26f31138a7f5850294e3bc4500e4283890f9f (diff) | |
| download | kernel-common-0b2aa8bed3e13892fcac77e4f50ec6e80125469d.tar.gz kernel-common-0b2aa8bed3e13892fcac77e4f50ec6e80125469d.tar.bz2 kernel-common-0b2aa8bed3e13892fcac77e4f50ec6e80125469d.zip | |
gpio: twl4030: Fix regression for twl gpio output
Commit c111feabe2e2 (gpio: twl4030: Cache the direction and output
states in private data) improved things in general, but caused a
regression for setting the GPIO output direction.
The change reorganized twl_direction_out() and twl_set() and swapped
the function names around in the process. While doing that, a bug got
introduced that's not obvious while reading the patch as it appears
as no change to the code.
The bug is we now call function twl4030_set_gpio_dataout() twice in
both twl_direction_out() and twl_set(). Instead, we should first
call twl_direction_out() in twl_direction_out() followed by
twl4030_set_gpio_dataout() in twl_set().
This regression probably has gone unnoticed for a long time as the
bootloader may have set the GPIO direction properly in many cases.
This fixes at least the LCD panel not turning on omap3 LDP for
example.
Cc: linux-gpio@vger.kernel.org
Cc: stable@vger.kernel.org #v3.9+
Reviewed-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Diffstat (limited to 'drivers/gpio')
| -rw-r--r-- | drivers/gpio/gpio-twl4030.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/gpio/gpio-twl4030.c b/drivers/gpio/gpio-twl4030.c index 0c7e891c8651..5738d5a7d849 100644 --- a/drivers/gpio/gpio-twl4030.c +++ b/drivers/gpio/gpio-twl4030.c @@ -354,17 +354,18 @@ 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) - twl4030_set_gpio_dataout(offset, value); + ret = twl4030_set_gpio_direction(offset, 0); priv->direction |= BIT(offset); mutex_unlock(&priv->mutex); twl_set(chip, offset, value); - return 0; + return ret; } static int twl_to_irq(struct gpio_chip *chip, unsigned offset) |