[PATCH] arm64: dts: mediatek: mt8192-asurada: Add off-on-delay-us for pp3300_mipibrdg
AngeloGioacchino Del Regno
angelogioacchino.delregno at collabora.com
Tue Apr 30 01:17:05 PDT 2024
Il 29/04/24 11:53, Pin-yen Lin ha scritto:
> Set off-on-delay-us to 500000 us for pp3300_mipibrdg to make sure it
> complies with the panel sequence. Explicit configuration on the
> regulator node is required because mt8192-asurada uses the same power
> supply for the panel and the anx7625 DP bridge. So powering on/off the
> DP bridge could break the power sequence requirement for the panel.
>
> Fixes: f9f00b1f6b9b ("arm64: dts: mediatek: asurada: Add display regulators")
> Signed-off-by: Pin-yen Lin <treapking at chromium.org>
>
Uhm, there might be more to it - I don't think that this should ever happen.
The regulator is refcounted, so...
* Bridge on: panel goes off, but regulator doesn't turn off (refcount=1)
* Panel resume -> sequence respected (refcount=2 -> wait -> more vregs, etc)
* Bridge off: panel is already off (refcount=0)
* Bridge resume -> refcount=1, no panel commands yet
* Panel resume -> refcount=2, wait -> more vregs, etc
Can you please describe the issue that you're getting?
Cheers,
Angelo
> ---
>
> arch/arm64/boot/dts/mediatek/mt8192-asurada.dtsi | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/arch/arm64/boot/dts/mediatek/mt8192-asurada.dtsi b/arch/arm64/boot/dts/mediatek/mt8192-asurada.dtsi
> index 7a704246678f..08d71ddf3668 100644
> --- a/arch/arm64/boot/dts/mediatek/mt8192-asurada.dtsi
> +++ b/arch/arm64/boot/dts/mediatek/mt8192-asurada.dtsi
> @@ -147,6 +147,7 @@ pp3300_mipibrdg: regulator-3v3-mipibrdg {
> regulator-boot-on;
> gpio = <&pio 127 GPIO_ACTIVE_HIGH>;
> vin-supply = <&pp3300_g>;
> + off-on-delay-us = <500000>;
> };
>
> /* separately switched 3.3V power rail */
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