Hi Geert,
Thank you for the patch.
On Thursday 01 Jun 2017 12:27:00 Geert Uytterhoeven wrote:
> Configuration of the lcd0 pinmux group and GPIO hog for the external
> GPIO mux are done using a single device node, causing the "output-high"
> property to be applied to both. This will fail for the pinmux group,
> but doesn't cause any harm, as the failure is ignored silently.
>
> However, after "pinctrl: sh-pfc: propagate errors on group config", the
> failure will become fatal, leading to a broken display:
>
> sh-pfc e6050000.pin-controller: pin_config_group_set op failed for group
> 102 sh-pfc e6050000.pin-controller: Error applying setting, reverse things
> back sh-pfc e6050000.pin-controller: failed to select default state
>
> Move the GPIO hog to its own node to fix this.
>
> Fixes: ffd2f9a5afb730b9 ("ARM: shmobile: armadillo800eva dts: Add pinctrl
> and gpio-hog for lcdc0") Signed-off-by: Geert Uytterhoeven
> <geert+renesas@xxxxxxxxx>
> ---
> This is a hard dependency for "pinctrl: sh-pfc: propagate errors on
> group config" (https://patchwork.kernel.org/patch/9186713/).
>
> v2:
> - Keep the GPIO hog, but move it to its own node, instead of using
> another level of subnodes. As the GPIO hog node is not referenced from
> a pinctrl-0 property, pinconf doesn't fail with "No pin or group
> provided in DT node".
I like this approach better, it allows us to drive the output instead of
pulling it up, without requiring a full implementation of output drive control
in the pfc driver.
Acked-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> ---
> arch/arm/boot/dts/r8a7740-armadillo800eva.dts | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/arch/arm/boot/dts/r8a7740-armadillo800eva.dts
> b/arch/arm/boot/dts/r8a7740-armadillo800eva.dts index
> 297b1f10f7346a9f..8c85d3ee5f5e7bfd 100644
> --- a/arch/arm/boot/dts/r8a7740-armadillo800eva.dts
> +++ b/arch/arm/boot/dts/r8a7740-armadillo800eva.dts
> @@ -273,7 +273,9 @@
> lcd0_pins: lcd0 {
> groups = "lcd0_data24_0", "lcd0_lclk_1", "lcd0_sync";
> function = "lcd0";
> + };
>
> + lcd0_mux {
> /* DBGMD/LCDC0/FSIA MUX */
> gpio-hog;
> gpios = <176 0>;
--
Regards,
Laurent Pinchart
