[PATCH v2] drm/panel-edp: Add LGD LP129WT112684 panel

[Tawheed Makhdoomi]

Add the LG Display LP129WT112684 12.9" 2880x1920 eDP panel used in the
Microsoft Surface Pro X (SQ1). Without this entry the panel is driven
with the conservative fallback timings and probe hits the "Unknown
panel" WARN.

I don't have a datasheet for this panel, so the timings are a guess
based on similar panels: delay_200_500_e200_d200 is what the other LGD
12.9" panel in the table (0x06b2, LP129WT232166) and most other LGD
entries use. With this entry the panel is detected and the display comes
up on every one of the 38 boots logged so far on my Surface Pro X (SQ1).

EDID, read from /sys/class/drm/card1-eDP-1/edid:

00 ff ff ff ff ff ff 00 30 e4 55 05 a0 28 09 00
00 1c 01 04 a5 1b 12 78 03 ee 95 a3 54 4c 99 26
0f 50 54 00 00 00 01 01 01 01 01 01 01 01 01 01
01 01 01 01 01 01 de 8a 40 78 b0 80 37 70 30 20
55 04 12 b7 10 00 00 19 00 00 00 fd 00 1e 3c 00
00 24 04 0a 48 14 14 14 14 00 00 00 00 fe 00 4c
47 44 5f 44 56 31 2e 30 5f 0a 20 20 00 00 00 fe
00 4c 50 31 32 39 57 54 31 31 32 36 38 34 00 41

  Manufacturer: LGD
  Model: 0x0555
  Made in: 2018
  Alphanumeric data strings: 'LGD_DV1.0_', 'LP129WT112684'
  DTD 1: 2880x1920 60.000 Hz 3:2 (274 mm x 183 mm), pixel clock 355.50 MHz

Signed-off-by: Tawheed Makhdoomi <_@xxxxxxxxxx>
---
Changes in v2:
- Include the EDID in the commit message.
- Say explicitly that the timings are a guess (no datasheet) and how
  they were picked, as Doug asked.
- v1: https://lore.kernel.org/r/20261112154444.417-1-_@xxxxxxxxxx

 drivers/gpu/drm/panel/panel-edp.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/panel/panel-edp.c b/drivers/gpu/drm/panel/panel-edp.c
index f7add22cc..8f7d7a3b2 100644
--- a/drivers/gpu/drm/panel/panel-edp.c
+++ b/drivers/gpu/drm/panel/panel-edp.c
@@ -2190,6 +2190,7 @@ static const struct edp_panel_entry edp_panels[] = {
 	EDP_PANEL_ENTRY('L', 'G', 'D', 0x052c, &delay_200_500_e200_d200, "LP133WF2-SPL7"),
 	EDP_PANEL_ENTRY('L', 'G', 'D', 0x0537, &delay_200_500_e200_d200, "Unknown"),
 	EDP_PANEL_ENTRY('L', 'G', 'D', 0x054a, &delay_200_500_e200_d200, "LP116WH8-SPC1"),
+	EDP_PANEL_ENTRY('L', 'G', 'D', 0x0555, &delay_200_500_e200_d200, "LP129WT112684"),
 	EDP_PANEL_ENTRY('L', 'G', 'D', 0x0567, &delay_200_500_e200_d200, "Unknown"),
 	EDP_PANEL_ENTRY('L', 'G', 'D', 0x05af, &delay_200_500_e200_d200, "Unknown"),
 	EDP_PANEL_ENTRY('L', 'G', 'D', 0x05f1, &delay_200_500_e200_d200, "Unknown"),
-- 
2.43.0