Re: [PATCH v2 2/9] arm64: dts: imx8mp-phyboard-pollux-rdk: Add panel-timing node to panel-lvds node

[Marek Vasut]

On 10/12/24 9:35 AM, Liu Ying wrote:
Add a panel-timing node to panel-lvds node to override any fixed
display modes written in a panel driver.  This way, 74.25MHz clock
frequency specified in panel-timing node may accommodate 7-fold
519.75MHz "media_ldb" clock which is derived from 1.0395GHz
"video_pll1" clock.
This should suppress this LDB driver warning:
[   17.923709] fsl-ldb 32ec0000.blk-ctrl:bridge@5c: Configured LDB clock 
(72400000 Hz) does not match requested LVDS clock: 506800000 Hz

This also makes the display mode used by the panel pass mode validation
against pixel clock rate and "media_ldb" clock rate in a certain display
driver.

Fixes: 326d86e197fc ("arm64: dts: imx8mp-phyboard-pollux-rdk: add etml panel 
support")
Signed-off-by: Liu Ying <victor....@nxp.com>
---
v2:
* No change.

  .../dts/freescale/imx8mp-phyboard-pollux-rdk.dts  | 15 +++++++++++++++
  1 file changed, 15 insertions(+)

diff --git a/arch/arm64/boot/dts/freescale/imx8mp-phyboard-pollux-rdk.dts 
b/arch/arm64/boot/dts/freescale/imx8mp-phyboard-pollux-rdk.dts
index 50debe821c42..20cb5363cccb 100644
--- a/arch/arm64/boot/dts/freescale/imx8mp-phyboard-pollux-rdk.dts
+++ b/arch/arm64/boot/dts/freescale/imx8mp-phyboard-pollux-rdk.dts
@@ -37,6 +37,21 @@ panel1_lvds: panel-lvds {
                backlight = <&backlight_lvds>;
                power-supply = <&reg_vcc_3v3_sw>;
  
+		panel-timing {
+                       clock-frequency = <74250000>;
+                       hactive = <1280>;
+                       vactive = <800>;
+                       hfront-porch = <72>;
+                       hback-porch = <86>;
+                       hsync-len = <2>;
+                       vfront-porch = <15>;
+                       vback-porch = <21>;
+                       vsync-len = <2>;
+                       hsync-active = <0>;
+                       vsync-active = <0>;
+                       de-active = <1>;
+               };
There is an existing entry for this panel in panel-simple.c , please do 
not duplicate timings in the DT:

drivers/gpu/drm/panel/panel-simple.c:static const struct panel_desc 
edt_etml1010g3dra = {
drivers/gpu/drm/panel/panel-simple.c:   .timings = 
&edt_etml1010g3dra_timing,
drivers/gpu/drm/panel/panel-simple.c:           .compatible = 
"edt,etml1010g3dra",