From: Christopher Orr <[email protected]> [ Upstream commit 754dbf164acd4d22dd7a5241b1880f54546d68f2 ]
Introduce high-res OLED panel for the Dell XPS 9345 These timings were selected based on Alex Vinarkskis' commit, (6b3815c6815f07acc7eeffa8ae734d1a1c0ee817) for the LQ134N1 and seem to work fine for the high-res OLED panel on the 9345. The raw edid for this SHP panel is: 00 ff ff ff ff ff ff 00 4d 10 8f 15 00 00 00 00 2e 21 01 04 b5 1d 12 78 03 0f 95 ae 52 43 b0 26 0f 50 54 00 00 00 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 01 fd d7 00 a0 a0 40 fc 66 30 20 36 00 20 b4 10 00 00 18 00 00 00 fd 00 1e 78 cc cc 38 01 0a 20 20 20 20 20 20 00 00 00 fe 00 43 37 31 4d 31 81 4c 51 31 33 34 5a 31 00 00 00 00 00 02 41 0c 32 01 01 00 00 0b 41 0a 20 20 01 ea 70 20 79 02 00 20 00 13 8c 52 19 8f 15 00 00 00 00 2e 17 07 4c 51 31 33 34 5a 31 21 00 1d 40 0b 08 07 00 0a 40 06 88 e1 fa 51 3d a4 b0 66 62 0f 02 45 54 d0 5f d0 5f 00 34 13 78 26 00 09 06 00 00 00 00 00 41 00 00 22 00 14 d9 6f 08 05 ff 09 9f 00 2f 00 1f 00 3f 06 5d 00 02 00 05 00 25 01 09 d9 6f 08 d9 6f 08 1e 78 80 81 00 0b e3 05 80 00 e6 06 05 01 6a 6a 39 00 00 00 00 00 00 58 90 Signed-off-by: Christopher Orr <[email protected]> Reviewed-by: Douglas Anderson <[email protected]> Signed-off-by: Douglas Anderson <[email protected]> Link: https://lore.kernel.org/r/aJKvm3SlhLGHW4qn@jander Signed-off-by: Sasha Levin <[email protected]> --- LLM Generated explanations, may be completely bogus: YES - What changes: Adds a single EDID‑based quirk entry for the Sharp eDP panel used in Dell XPS 13 9345 high‑res OLED: `EDP_PANEL_ENTRY('S','H','P', 0x158f, &delay_200_500_p2e100, "LQ134Z1")`, placed alongside existing SHP entries and using the same delay profile as the related LQ134N1 panel. This goes into the vendor/product‑sorted `edp_panels[]` table in drivers/gpu/drm/panel/panel-edp.c:1859 and the SHP block around drivers/gpu/drm/panel/panel-edp.c:2030. The delay profile referenced is defined at drivers/gpu/drm/panel/panel-edp.c:1727. - Why it matters (bugfix, not a feature): - The edp_panel table drives panel power‑sequencing timings by EDID. Unknown panels fall back to conservative timings via generic detection (drivers/gpu/drm/panel/panel-edp.c:759) which sets only unprepare/enable and notably does not set `prepare_to_enable` (drivers/gpu/drm/panel/panel-edp.c:740). For this class of SHP panels, the correct behavior requires a non‑zero `prepare_to_enable` (100 ms). - Power‑on sequencing uses `prepare_to_enable` to ensure the backlight/enable step doesn’t occur too soon after prepare/HPD (drivers/gpu/drm/panel/panel-edp.c:542). Without the EDID match and the `p2e100` profile, the code won’t enforce this wait, which is known to cause intermittent black screens/boot failures for the closely related SHP LQ134N1 (added earlier in this file, drivers/gpu/drm/panel/panel-edp.c:2030, by commit 6b3815c6815f). The new entry applies the same proven sequencing to the high‑res OLED variant (product ID 0x158f), preventing the same failure mode. - In short: This is a quirk fix for a specific hardware panel ID that makes the internal display reliably work on a common laptop variant; without it, users can hit black screens or unreliable bring‑up. - Scope and risk: - Minimal and contained: it only affects panels that present EDID vendor "SHP" product 0x158f. It doesn’t change logic or touch other devices or subsystems. - Uses an existing, well‑tested delay profile (`delay_200_500_p2e100`), already applied to other panels (e.g., SHP LQ134N1 at drivers/gpu/drm/panel/panel-edp.c:2030, IVO panels at drivers/gpu/drm/panel/panel-edp.c:1999–2000), further reducing risk. - No architectural changes; only a single entry in a quirk table. - Stable backport criteria: - Fixes a real user‑visible malfunction (internal display not reliably coming up) on supported hardware; not a feature. - Change is tiny, targeted, and low risk; confined to DRM eDP panel quirk table. - No side effects beyond enabling correct sequencing on the matching panel ID. - While the commit message doesn’t include “Fixes:”/“Cc: stable”, the technical nature (EDID quirk for correct power sequencing) and precedent from the LQ134N1 entry demonstrate this is a classic stable‑eligible panel quirk fix. Key code references: - New entry location (adjacent context): drivers/gpu/drm/panel/panel- edp.c:2030 - Delay profile used: drivers/gpu/drm/panel/panel-edp.c:1727 - Fallback (no EDID match) lacks prepare_to_enable: drivers/gpu/drm/panel/panel-edp.c:740, 759 - Sequencing logic using prepare_to_enable: drivers/gpu/drm/panel/panel- edp.c:542 - Existing related SHP LQ134N1 entry (same delay): drivers/gpu/drm/panel/panel-edp.c:2030 Conclusion: Backporting this quirk yields a reliable, low‑risk fix for users of the Dell XPS 13 9345 high‑res OLED variant. 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 d0aa602ecc9de..a926f81f7a2e1 100644 --- a/drivers/gpu/drm/panel/panel-edp.c +++ b/drivers/gpu/drm/panel/panel-edp.c @@ -2035,6 +2035,7 @@ static const struct edp_panel_entry edp_panels[] = { EDP_PANEL_ENTRY('S', 'H', 'P', 0x1523, &delay_80_500_e50, "LQ140M1JW46"), EDP_PANEL_ENTRY('S', 'H', 'P', 0x153a, &delay_200_500_e50, "LQ140T1JH01"), EDP_PANEL_ENTRY('S', 'H', 'P', 0x154c, &delay_200_500_p2e100, "LQ116M1JW10"), + EDP_PANEL_ENTRY('S', 'H', 'P', 0x158f, &delay_200_500_p2e100, "LQ134Z1"), EDP_PANEL_ENTRY('S', 'H', 'P', 0x1593, &delay_200_500_p2e100, "LQ134N1"), EDP_PANEL_ENTRY('S', 'T', 'A', 0x0004, &delay_200_500_e200, "116KHD024006"), -- 2.51.0
