2024-04-12 07:56:27

by Chen-Yu Tsai

[permalink] [raw]
Subject: [PATCH] arm64: dts: mediatek: mt8183-kukui: Drop bogus output-enable property

The "output-enable" property is set on uart1's RTS pin. This is bogus
because the hardware does not actually have a controllable output
buffer. Secondly, the implementation incorrectly treats this property
as a request to switch the pin to GPIO output. This does not fit the
intended semantic of "output-enable" and it does not have any affect
either because the pin is muxed to the UART function, not the GPIO
function.

Drop the property.

Fixes: cd894e274b74 ("arm64: dts: mt8183: Add krane-sku176 board")
Signed-off-by: Chen-Yu Tsai <[email protected]>
---
arch/arm64/boot/dts/mediatek/mt8183-kukui.dtsi | 2 --
1 file changed, 2 deletions(-)

diff --git a/arch/arm64/boot/dts/mediatek/mt8183-kukui.dtsi b/arch/arm64/boot/dts/mediatek/mt8183-kukui.dtsi
index f934b8aad3ed..75c799a6adb4 100644
--- a/arch/arm64/boot/dts/mediatek/mt8183-kukui.dtsi
+++ b/arch/arm64/boot/dts/mediatek/mt8183-kukui.dtsi
@@ -797,7 +797,6 @@ pins-tx {
};
pins-rts {
pinmux = <PINMUX_GPIO47__FUNC_URTS1>;
- output-enable;
};
pins-cts {
pinmux = <PINMUX_GPIO46__FUNC_UCTS1>;
@@ -816,7 +815,6 @@ pins-tx {
};
pins-rts {
pinmux = <PINMUX_GPIO47__FUNC_URTS1>;
- output-enable;
};
pins-cts {
pinmux = <PINMUX_GPIO46__FUNC_UCTS1>;
--
2.44.0.683.g7961c838ac-goog



Subject: Re: [PATCH] arm64: dts: mediatek: mt8183-kukui: Drop bogus output-enable property

Il 12/04/24 09:56, Chen-Yu Tsai ha scritto:
> The "output-enable" property is set on uart1's RTS pin. This is bogus
> because the hardware does not actually have a controllable output
> buffer. Secondly, the implementation incorrectly treats this property
> as a request to switch the pin to GPIO output. This does not fit the
> intended semantic of "output-enable" and it does not have any affect
> either because the pin is muxed to the UART function, not the GPIO
> function.
>
> Drop the property.
>
> Fixes: cd894e274b74 ("arm64: dts: mt8183: Add krane-sku176 board")
> Signed-off-by: Chen-Yu Tsai <[email protected]>

Reviewed-by: AngeloGioacchino Del Regno <[email protected]>