[Letux-kernel] drm/omap: Remove panel-dpi driver

[H. Nikolaus Schaller]

Hi Tomi,
just a short update.

> Am 11.04.2019 um 09:19 schrieb Tomi Valkeinen <tomi.valkeinen at ti.com>:
> 
>>>>> You will need the panel data to be added to the simple panel driver, as
>>>>> it won't read the timings from the DT (unfortunately, in my opinion).
>>>> 
>>>> Hm. How does this work? Is there a description? I have no experience with
>>>> DRM simple panel.
>>> 
>>> See drivers/gpu/drm/panel/panel-simple.c, it just has a list of
>>> compatibles, and pointers to the (more or less) same data as is in the
>>> DT. And see a commit that adds a new panel, e.g. "drm/panel: simple: Add
>>> OSD070T1718-19TS panel support".
>> 
>> Ok, I see. So the task is converting the nice and tested DTS properties to
>> magic numbers in code... Let's hope without introducing new bugs.

I have started with this and it was easy to add new panels to the database
in panel-simple. But it seems not to probe successfully and omapdss does
not initialize. Even if I modprobe panel_simple manually.

The DTS looks like (is still working with 5.1 panel-dpi driver):

/ {
	model = "Goldelico GTA04b3/Letux 7004";
	lcd: lcd {
		compatible =	"sharp,lq070y3dg3b",
				"panel-dpi";
		label = "lcd";
		enable-gpios = <&gpio1 12 0>;

		panel-timing {
			clock-frequency = <33260000>;

			hback-porch = <64>;
			hactive = <800>;
			hfront-porch = <64>;
			hsync-len = <128>;

			vback-porch = <35>;
			vactive = <480>;
			vfront-porch = <8>;
			vsync-len = <2>;

			hsync-active = <0>;
			vsync-active = <0>;
			de-active = <1>;
			pixelclk-active = <1>;

		};

		port {
			lcd_in: endpoint {
				remote-endpoint = <&dpi_out>;
			};
		};
	};
};

and the module database knows the compatible string:

root at letux:~# modprobe -c | fgrep sharp,lq070y3dg3b
alias of:N*T*Csharp,lq070y3dg3b panel_simple
alias of:N*T*Csharp,lq070y3dg3bC* panel_simple
root at letux:~# 

Next thing I plan do is to find out why the panel-simple driver is not matched
by the panel DTS record.

BR,
Nikolaus