| Message ID | 20231109100606.1245545-7-wenst@chromium.org |
|---|---|
| State | New |
| Headers | show |
| Series | of: Introduce hardware prober driver | expand |
On Thu, Nov 09, 2023 at 06:06:03PM +0800, Chen-Yu Tsai wrote: > In cases where the same Chromebook model is manufactured with different > components (MIPI DSI panels, MIPI CSI camera sensors, or trackpad / > touchscreens with conflicting addresses), a different SKU ID is > allocated to each specific combination. This SKU ID is exported by the > bootloader into the device tree, and can be used to "discover" which > combination is present on the current machine. Thus we no longer have > to specify separate compatible strings for each of them. You just broke an existing kernel with a new DT having this change. Just because you come up with a new way to do things, doesn't mean you can remove the old way. > > Remove the SKU specific compatible strings for Google Krane. > > Signed-off-by: Chen-Yu Tsai <wenst@chromium.org> > --- > Documentation/devicetree/bindings/arm/mediatek.yaml | 3 --- > 1 file changed, 3 deletions(-) > > diff --git a/Documentation/devicetree/bindings/arm/mediatek.yaml b/Documentation/devicetree/bindings/arm/mediatek.yaml > index a4541855a838..ef3dfb286814 100644 > --- a/Documentation/devicetree/bindings/arm/mediatek.yaml > +++ b/Documentation/devicetree/bindings/arm/mediatek.yaml > @@ -186,9 +186,6 @@ properties: > - const: mediatek,mt8183 > - description: Google Krane (Lenovo IdeaPad Duet, 10e,...) > items: > - - enum: > - - google,krane-sku0 > - - google,krane-sku176 > - const: google,krane > - const: mediatek,mt8183 > - description: Google Willow (Acer Chromebook 311 C722/C722T) > -- > 2.42.0.869.gea05f2083d-goog >
Hi, On Fri, Nov 10, 2023 at 1:04 PM Rob Herring <robh@kernel.org> wrote: > > On Thu, Nov 09, 2023 at 06:06:03PM +0800, Chen-Yu Tsai wrote: > > In cases where the same Chromebook model is manufactured with different > > components (MIPI DSI panels, MIPI CSI camera sensors, or trackpad / > > touchscreens with conflicting addresses), a different SKU ID is > > allocated to each specific combination. This SKU ID is exported by the > > bootloader into the device tree, and can be used to "discover" which > > combination is present on the current machine. Thus we no longer have > > to specify separate compatible strings for each of them. > > You just broke an existing kernel with a new DT having this change. > > Just because you come up with a new way to do things, doesn't mean you > can remove the old way. I was wondering about that, actually. My understanding was that what Chen-Yu was doing here was correct, but I'm happy to be educated. Specifically, I think that after his series old device trees will continue to boot just fine. ...so if someone took a device tree from before his series and booted it on a kernel after his series that everything would be hunky dory. If that doesn't work then, I agree, that should be fixed. However, here, he is documenting what the "latest and greatest" device tree should look at and that matches what's checked into the "dts" directory. In general, I thought that yaml files didn't necessarily always document old/deprecated ways of doing things and just focused on documenting the new/best way. Now, obviously, if someone took a new device tree and tried to put it on an old kernel then it wouldn't work, but I was always under the impression that wasn't a requirement. -Doug
diff --git a/Documentation/devicetree/bindings/arm/mediatek.yaml b/Documentation/devicetree/bindings/arm/mediatek.yaml index a4541855a838..ef3dfb286814 100644 --- a/Documentation/devicetree/bindings/arm/mediatek.yaml +++ b/Documentation/devicetree/bindings/arm/mediatek.yaml @@ -186,9 +186,6 @@ properties: - const: mediatek,mt8183 - description: Google Krane (Lenovo IdeaPad Duet, 10e,...) items: - - enum: - - google,krane-sku0 - - google,krane-sku176 - const: google,krane - const: mediatek,mt8183 - description: Google Willow (Acer Chromebook 311 C722/C722T)
In cases where the same Chromebook model is manufactured with different components (MIPI DSI panels, MIPI CSI camera sensors, or trackpad / touchscreens with conflicting addresses), a different SKU ID is allocated to each specific combination. This SKU ID is exported by the bootloader into the device tree, and can be used to "discover" which combination is present on the current machine. Thus we no longer have to specify separate compatible strings for each of them. Remove the SKU specific compatible strings for Google Krane. Signed-off-by: Chen-Yu Tsai <wenst@chromium.org> --- Documentation/devicetree/bindings/arm/mediatek.yaml | 3 --- 1 file changed, 3 deletions(-)