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

From: Eugen Hristev
Date: Wed Aug 16 2023 - 07:18:37 EST


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@xxxxxxxxxxxx>
---
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@0 {
compatible = "winbond,w25q64dw", "jedec,spi-nor";
reg = <0>;
spi-max-frequency = <25000000>;
+ disable-quad-mode;
};
};