Commit 0b2aa8be authored by Tony Lindgren's avatar Tony Lindgren

gpio: twl4030: Fix regression for twl gpio output

Commit c111feab (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: default avatarPeter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: default avatarLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: default avatarTony Lindgren <tony@atomide.com>
parent cae26f31
...@@ -354,17 +354,18 @@ static void twl_set(struct gpio_chip *chip, unsigned offset, int value) ...@@ -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) static int twl_direction_out(struct gpio_chip *chip, unsigned offset, int value)
{ {
struct gpio_twl4030_priv *priv = to_gpio_twl4030(chip); struct gpio_twl4030_priv *priv = to_gpio_twl4030(chip);
int ret = -EINVAL;
mutex_lock(&priv->mutex); mutex_lock(&priv->mutex);
if (offset < TWL4030_GPIO_MAX) if (offset < TWL4030_GPIO_MAX)
twl4030_set_gpio_dataout(offset, value); ret = twl4030_set_gpio_direction(offset, 0);
priv->direction |= BIT(offset); priv->direction |= BIT(offset);
mutex_unlock(&priv->mutex); mutex_unlock(&priv->mutex);
twl_set(chip, offset, value); twl_set(chip, offset, value);
return 0; return ret;
} }
static int twl_to_irq(struct gpio_chip *chip, unsigned offset) static int twl_to_irq(struct gpio_chip *chip, unsigned offset)
......
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