[PATCH 11/11] ARM: versatile: move CLCD configuration to device tree

[Linus Walleij]

On Tue, Feb 23, 2016 at 10:34 AM, Arnd Bergmann <arnd at arndb.de> wrote:
> On Tuesday 23 February 2016 10:08:05 Linus Walleij wrote:
>> I will think of a better solution, if any, for this for v4.6, but will
>> put forward something that handles the Nomadik and all the
>> other ARM reference designs for now.
>>
>
> How about still describing all known panels in the DT marked 'status="disabled"',
> but then having a minimal piece of board specific code that just enables
> whichever one gets detected at boot time?

Close but no cigar :D

It means that all panels (enabled and all disabled) have to have the same
endpoint in the of_graph.

I tried it:

    panel at 0 {
        compatible = "panel-dpi";
        port {
            clcd_panel: endpoint {
                remote-endpoint = <&clcd_pads>;
            };
        };
(...)

    panel at 1 {
        compatible = "panel-dpi";
        port {
            clcd_panel: endpoint {
                remote-endpoint = <&clcd_pads>;
            };
        };
(...)


        display at 10120000 {
(...)
            port {
(...)
                clcd_pads: endpoint at 0 {
                    reg = <0>;
                    remote-endpoint = <&clcd_panel>;
                    arm,pl11x,tft-r0g0b0-pads = <1 7 13>;
                };
            };



Building the device tree:

ERROR (duplicate_label): ERROR (duplicate_label): Duplicate label
'clcd_panel' on /panel at 1/port/endpoint and /panel at 0/port/endpoint
Duplicate label 'clcd_panel' on /panel at 1/port/endpoint and
/panel at 0/port/endpoint

So the dtc does not allow duplicate node labels for the phandle
even if the node it resides in is disabled. Tough luck...

Yours,
Linus Walleij