From: Rob Clark <robdclark@xxxxxxxxxxxx> For devices that have one of several possible panels installed, the panel-id property gives firmware a generic way to locate and enable the panel node corresponding to the installed panel. Example of how to use this property: ivo_panel { compatible = "ivo,m133nwf4-r0"; panel-id = <0xc5>; status = "disabled"; ports { port { ivo_panel_in_edp: endpoint { remote-endpoint = <&sn65dsi86_out_ivo>; }; }; }; }; boe_panel { compatible = "boe,nv133fhm-n61"; panel-id = <0xc4>; status = "disabled"; ports { port { boe_panel_in_edp: endpoint { remote-endpoint = <&sn65dsi86_out_boe>; }; }; }; }; sn65dsi86: bridge@2c { compatible = "ti,sn65dsi86"; ports { #address-cells = <1>; #size-cells = <0>; port@0 { reg = <0>; sn65dsi86_in_a: endpoint { remote-endpoint = <&dsi0_out>; }; }; port@1 { reg = <1>; sn65dsi86_out_boe: endpoint@c4 { remote-endpoint = <&boe_panel_in_edp>; }; sn65dsi86_out_ivo: endpoint@c5 { remote-endpoint = <&ivo_panel_in_edp>; }; }; }; }; Signed-off-by: Rob Clark <robdclark@xxxxxxxxxxxx> --- .../bindings/display/panel/panel-common.yaml | 26 +++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/Documentation/devicetree/bindings/display/panel/panel-common.yaml b/Documentation/devicetree/bindings/display/panel/panel-common.yaml index ef8d8cdfcede..6113319b91dd 100644 --- a/Documentation/devicetree/bindings/display/panel/panel-common.yaml +++ b/Documentation/devicetree/bindings/display/panel/panel-common.yaml @@ -75,6 +75,32 @@ properties: in the device graph bindings defined in Documentation/devicetree/bindings/graph.txt. + panel-id: + description: + To support the case where one of several different panels can be installed + on a device, the panel-id property can be used by the firmware to identify + which panel should have it's status changed to "ok". This property is not + used by the HLOS itself. + + For a device with multiple potential panels, a node for each potential + should be defined with status = "disabled", and an appropriate panel-id + property. The video data producer should be setup with endpoints going to + each possible panel. The firmware will find the dt node with a panel-id + matching the actual panel installed, and change it's status to "ok". + + The exact method the firmware uses to determine the panel-id of the installed + panel is outside the scope of this binding, but a few examples are + + 1) u-boot module reading a value from a u-boot env var + 2) EFI driver module reading a value from an EFI variable + 3) device specific firmware reading some device specific GPIOs or + e-fuse + + The panel-id values are an opaque integer. They can be sparse. The only + important thing is that each possible panel in the system has a unique + panel-id, and that the values configured in the device's DTB match the + values that the firmware is looking for. + ddc-i2c-bus: $ref: /schemas/types.yaml#/definitions/phandle description: -- 2.23.0