On Sat, Mar 29, 2025 at 02:54:27PM +0100, Luca Weiss wrote: > Hi all, > > On 2/24/25 9:16 AM, Krzysztof Kozlowski wrote: > > On 23/02/2025 16:29, Luca Weiss wrote: > > > Hi Krzysztof, > > > > > > On 23-02-2025 12:54 p.m., Krzysztof Kozlowski wrote: > > > > On Sat, Feb 22, 2025 at 06:58:05PM +0100, Luca Weiss wrote: > > > > > Himax HX83112B is a display driver IC used to drive LCD DSI panels. > > > > > Describe it and the Fairphone 3 panel from DJN using it. > > > > > > > > > > Signed-off-by: Luca Weiss <[email protected]> > > > > > --- > > > > > .../bindings/display/panel/himax,hx83112b.yaml | 75 > > > > > ++++++++++++++++++++++ > > > > > 1 file changed, 75 insertions(+) > > > > > > > > > > diff --git > > > > > a/Documentation/devicetree/bindings/display/panel/himax,hx83112b.yaml > > > > > b/Documentation/devicetree/bindings/display/panel/himax,hx83112b.yaml > > > > > new file mode 100644 > > > > > index > > > > > 0000000000000000000000000000000000000000..e6bd4b33d40be98e479d84617aea6d2af0df70e4 > > > > > --- /dev/null > > > > > +++ > > > > > b/Documentation/devicetree/bindings/display/panel/himax,hx83112b.yaml > > > > > @@ -0,0 +1,75 @@ > > > > > +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause > > > > > +%YAML 1.2 > > > > > +--- > > > > > +$id: http://devicetree.org/schemas/display/panel/himax,hx83112b.yaml# > > > > > +$schema: http://devicetree.org/meta-schemas/core.yaml# > > > > > + > > > > > +title: Himax HX83112B-based DSI display panels > > > > > + > > > > > +maintainers: > > > > > + - Luca Weiss <[email protected]> > > > > > + > > > > > +description: > > > > > + The Himax HX83112B is a generic DSI Panel IC used to control > > > > > + LCD panels. > > > > > + > > > > > +allOf: > > > > > + - $ref: panel-common.yaml# > > > > > + > > > > > +properties: > > > > > + compatible: > > > > > + contains: > > > > > + const: djn,fairphone-fp3-panel > > > > > > > > Why no himax,hx83112b fallback? > > > > > > While this is the driver IC for this panel, I don't think there's any > > > "generic" init sequence that can successfully configure this panel, so > > > generic hx83112b driver could work I'd say. > > > > > > Hm, indeed usually this would mean no need for unusable fallback alone, > > but still drivers could use it for some common pieces of code. I imagine > > there could be a piece of init sequence which is generic. Or some piece > > of attributes. > > We already have examples of both approaches for panels - with generic > > fallback (himax,hx83102) and without (himax,hx83112a). > > > > @Rob > > what is your generic advice? Which of above (himax,hx83102 vs > > himax,hx83112a) should be used, if the fallback compatible cannot be > > used alone? > > I believe this thread is still pending of a resolution, based on the model > number I've found, I made the compatible "djn,98-03057-6598b-i" for v2, but > it's still a question whether himax,hx83112b should be part of the > compatible.
My 2c (note, not a DT maintainer or anything): no, the IC driver doesn't fully define panel programming, so it should not be used as a fallback compat. -- With best wishes Dmitry
