On Sun, Jun 30, 2019 at 2:36 PM Rob Clark robdclark@gmail.com wrote:
From: Rob Clark robdclark@chromium.org
The panel-id property in chosen can be used to communicate which panel, of multiple possibilities, is installed.
Signed-off-by: Rob Clark robdclark@chromium.org
Documentation/devicetree/bindings/chosen.txt | 69 ++++++++++++++++++++ 1 file changed, 69 insertions(+)
I need to update this file to say it's moved to the schema repository...
But I don't think that will matter...
diff --git a/Documentation/devicetree/bindings/chosen.txt b/Documentation/devicetree/bindings/chosen.txt index 45e79172a646..d502e6489b8b 100644 --- a/Documentation/devicetree/bindings/chosen.txt +++ b/Documentation/devicetree/bindings/chosen.txt @@ -68,6 +68,75 @@ on PowerPC "stdout" if "stdout-path" is not found. However, the "linux,stdout-path" and "stdout" properties are deprecated. New platforms should only use the "stdout-path" property.
+panel-id +--------
+For devices that have multiple possible display panels (multi-sourcing the +display panels is common on laptops, phones, tablets), this allows the +bootloader to communicate which panel is installed, e.g.
How does the bootloader figure out which panel? Why can't the kernel do the same thing?
+/ {
chosen {panel-id = <0xc4>;};ivo_panel {compatible = "ivo,m133nwf4-r0";power-supply = <&vlcm_3v3>;no-hpd;ports {port {ivo_panel_in_edp: endpoint {remote-endpoint = <&sn65dsi86_out_ivo>;};};};};boe_panel {compatible = "boe,nv133fhm-n61";
Both panels are going to probe. So the bootloader needs to disable the not populated panel setting 'status' (or delete the node). If you do that, do you even need 'panel-id'?
power-supply = <&vlcm_3v3>;no-hpd;ports {port {boe_panel_in_edp: endpoint {remote-endpoint = <&sn65dsi86_out_boe>;};};};};display_or_bridge_device {ports {#address-cells = <1>;#size-cells = <0>;...port@0 {#address-cells = <1>;#size-cells = <0>;reg = <0>;endpoint@c4 {reg = <0xc4>;
What does this number represent? It is supposed to be defined by the display_or_bridge_device, not a specific panel.
We also need to consider how the DSI case with panels as children of the DSI controller would work and how this would work with multiple displays each having multiple panel options.
Rob