Re: [PATCH v4 4/4] arm64: dts: mediatek: mt7988: add pinctrl support

[AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>]

Il 09/10/24 18:52, Frank Wunderlich ha scritto:
> From: Frank Wunderlich <frank-w@public-files.de>
> 
> Add mt7988a pinctrl node.
> 
> Signed-off-by: Frank Wunderlich <frank-w@public-files.de>
> ---
> v2:
> - fix wrong alignment of reg values
> ---
>   arch/arm64/boot/dts/mediatek/mt7988a.dtsi | 241 ++++++++++++++++++++++
>   1 file changed, 241 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/mediatek/mt7988a.dtsi b/arch/arm64/boot/dts/mediatek/mt7988a.dtsi
> index c9649b815276..7e15934efe0b 100644
> --- a/arch/arm64/boot/dts/mediatek/mt7988a.dtsi
> +++ b/arch/arm64/boot/dts/mediatek/mt7988a.dtsi
> @@ -3,6 +3,7 @@
>   #include <dt-bindings/clock/mediatek,mt7988-clk.h>
>   #include <dt-bindings/interrupt-controller/arm-gic.h>
>   #include <dt-bindings/phy/phy.h>
> +#include <dt-bindings/pinctrl/mt65xx.h>
>   
>   / {
>   	compatible = "mediatek,mt7988a";
> @@ -105,6 +106,246 @@ clock-controller@1001e000 {
>   			#clock-cells = <1>;
>   		};
>   
> +		pio: pinctrl@1001f000 {
> +			compatible = "mediatek,mt7988-pinctrl";
> +			reg = <0 0x1001f000 0 0x1000>,
> +			      <0 0x11c10000 0 0x1000>,
> +			      <0 0x11d00000 0 0x1000>,
> +			      <0 0x11d20000 0 0x1000>,
> +			      <0 0x11e00000 0 0x1000>,
> +			      <0 0x11f00000 0 0x1000>,
> +			      <0 0x1000b000 0 0x1000>;
> +			reg-names = "gpio", "iocfg_tr",
> +				    "iocfg_br", "iocfg_rb",
> +				    "iocfg_lb", "iocfg_tl", "eint";
> +			gpio-controller;
> +			#gpio-cells = <2>;
> +			gpio-ranges = <&pio 0 0 84>;
> +			interrupt-controller;
> +			interrupts = <GIC_SPI 225 IRQ_TYPE_LEVEL_HIGH>;
> +			interrupt-parent = <&gic>;
> +			#interrupt-cells = <2>;
> +
> +			mdio0_pins: mdio0-pins {
> +				mux {
> +					function = "eth";
> +					groups = "mdc_mdio0";
> +				};
> +
> +				conf {
> +					pins = "SMI_0_MDC", "SMI_0_MDIO";
> +					drive-strength = <MTK_DRIVE_8mA>;

Please do *not* use the MTK_DRIVE_(x)mA definitions anymore.

Here it is `drive-strength = <8>`.

> +				};
> +			};
> +
> +			i2c0_pins: i2c0-g0-pins {
> +				mux {
> +					function = "i2c";
> +					groups = "i2c0_1";
> +				};
> +			};
> +
> +			i2c1_pins: i2c1-g0-pins {
> +				mux {
> +					function = "i2c";
> +					groups = "i2c1_0";
> +				};
> +			};

Whatever pin can be configured with one or multiple groups that can be different
must *not* be in the SoC dtsi, but rather in the *board* dts(i) file, as the wanted
configuration of those pins is *not* soc-specific but board-specific.

 From a fast look, I can see that at least the I2C pins can be assigned to different
functions: for example, pins 15+16 can be either of i2c0_1, *or* u30_phy_i2c0, *or*
u32_phy_i2c0, *or* xfi_phy0_i2c1 ... or others, even.

Finally - I think that *most* of the muxing that you're declaring here must instead
go to your board specific devicetree and not in mt7988a.dtsi.

Cheers,
Angelo