[PATCH 5/8] gpio: twl4030: Fix regression for twl gpio output

Linus Walleij linus.walleij at linaro.org
Mon Nov 18 17:45:53 EST 2013

On Thu, Nov 14, 2013 at 3:35 AM, Tony Lindgren <tony at atomide.com> wrote:

> 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: Linus Walleij <linus.walleij at linaro.org>
> Cc: Peter Ujfalusi <peter.ujfalusi at ti.com>
> Cc: linux-gpio at vger.kernel.org
> Signed-off-by: Tony Lindgren <tony at atomide.com>
> ---
> If this looks OK, I'd like to merge this as a fix via arm-soc tree
> along with the other patches in this series as my later patches
> depend on patches in this series.

Acked-by: Linus Walleij <linus.walleij at linaro.org>

Linus Walleij

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