Re: [PATCH 3/4] OMAPDSS: panel-sharp-ls037v7dw01: add device tree support

* Tomi Valkeinen [off-list ref] [140509 00:24]:

On 09/05/14 02:33, Tony Lindgren wrote:

quoted

+Example when connected to a omap2+ based device:
+
+	lcd0: display {
+		compatible = "sharp,ls037v7dw01";
+		power-supply = <&lcd_3v3>;
+		enable-gpios = <&gpio5 24 GPIO_ACTIVE_HIGH>;	/* gpio152, lcd INI */
+		reset-gpios = <&gpio5 27 GPIO_ACTIVE_HIGH>;	/* gpio155, lcd RESB */
+		mode-gpios = <&gpio5 26 GPIO_ACTIVE_HIGH	/* gpio154, lcd MO */
+			      &gpio1 2 GPIO_ACTIVE_HIGH		/* gpio2, lcd LR */
+			      &gpio1 3 GPIO_ACTIVE_HIGH>;	/* gpio3, lcd UD */
+
+		panel-timing {
+			clock-frequency = <19200000>;
+			hback-porch = <28>;
+			hactive = <480>;
+			hfront-porch = <1>;
+			hsync-len = <2>;
+			vback-porch = <1>;
+			vactive = <640>;
+			vfront-porch = <1>;
+			vsync-len = <1>;
+			hsync-active = <0>;
+			vsync-active = <0>;
+			de-active = <1>;
+			pixelclk-active = <1>;
+		};

I don't think we should define panel-timing here. We know it's
sharp,ls037v7dw01, so the driver knows the video timings. Also, if we
would extend the driver to support both resolution modes, it needs to
support two different timings, so the above doesn't work in that case
either.

OK. It seems we can have at least two different timings for this panel,
the VGA timing above and the QVGA timings that LDP uses that are listed
in the .dts changes.
 

Although if the MO gpio is not controlled by the driver, we should tell
the driver whether that gpio is high or low.

What do you have in mind for telling that? We should also tell the
orientation of the panel:

EVM	VGA	omapfb.rotate=3
LDP	QVGA	omapfb.rotate=0

Do you have something in mind for that?
 

At the moment our display drivers are OMAP specific, and for that reason
we should prefix the compatible strings with "omapdss,". For example,
drivers/video/fbdev/omap2/displays-new/panel-dsi-cm.c:

	{ .compatible = "omapdss,panel-dsi-cm", },

But we should still have the right compatible string in the .dts, so we
convert the compatible name in arch/arm/mach-omap2/display.c, with
'dss_compat_conv_list' array, to which this panel's name should be added.

Oh so what do you want to have in the .dts file then?

Regards,

Tony