[PATCH 3/4] arm64: dts: mediatek: mt8183: disable quad mode for spi nor

Eugen Hristev eugen.hristev at collabora.com
Wed Aug 16 04:17:41 PDT 2023


On 8/15/23 18:31, Hsin-Yi Wang wrote:
> Some of the SKUs are using gigadevice gd25lq64c flash chip. The chip
> default enables quad mode, which results in the write protect pin set to
> IO pin. In mt8183 kukui, we won't use quad enable for all SKUs, so apply
> the property to disable spi nor's quad mode.

Hi Hsin-Yi,

To me this property, and the way you 'apply' it, makes me think that you 
are using the devicetree as a configuration and not a description of the 
hardware itself.
I think the driver should decide whether to use quad or not depending on 
the situation or the pinout of the device (as in your case quad mode 
overlaps with the WP pin)

Eugen

> 
> Signed-off-by: Hsin-Yi Wang <hsinyi at chromium.org>
> ---
>   arch/arm64/boot/dts/mediatek/mt8183-kukui.dtsi | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/arch/arm64/boot/dts/mediatek/mt8183-kukui.dtsi b/arch/arm64/boot/dts/mediatek/mt8183-kukui.dtsi
> index 6ce16a265e053..8e4761e2b8ff4 100644
> --- a/arch/arm64/boot/dts/mediatek/mt8183-kukui.dtsi
> +++ b/arch/arm64/boot/dts/mediatek/mt8183-kukui.dtsi
> @@ -877,6 +877,7 @@ w25q64dw: flash at 0 {
>   		compatible = "winbond,w25q64dw", "jedec,spi-nor";
>   		reg = <0>;
>   		spi-max-frequency = <25000000>;
> +		disable-quad-mode;
>   	};
>   };
>   




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