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drm/panel: simple: Add Raystar RFF500F-AWH-DNN enable delay

PATCH Applied Fabio Estevam 2 participants 3 messages Sep 9 – Oct 2

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Stable branch DRM drivers DRM misc DRM panel drivers
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Fabio Estevam

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#0 lore raw

PATCH 1/1 drm/panel: simple: Add Raystar RFF500F-AWH-DNN enable delay

From: Fabio Estevam <[email protected]>

The RFF500F-AWH-DNN datasheet requires a minimum delay of 250 ms between display signal output and backlight power-on.

Without this delay, the backlight can expose unsettled panel contents during display startup, resulting in a brief bright flash.

Set the panel enable delay to the datasheet-specified minimum.

Cc [email protected]
Fixes 1b2a9ec82099 ("drm/panel: simple: Add Raystar RFF500F-AWH-DNN panel entry")
Signed-off-by Fabio Estevam <[email protected]>
---
 drivers/gpu/drm/panel/panel-simple.c | 3 +++
 1 file changed, 3 insertions(+)
drivers/gpu/drm/panel/panel-simple.c +3 -0
index c95964ba25a9..70e37ff12c9e 100644
@@ -4354,6 +4354,9 @@ static const struct panel_desc raystar_rff500f_awh_dnn = {
 		.width = 108,
 		.height = 65,
 	},
+	.delay = {
+		.enable = 250,
+	},
 	.bus_format = MEDIA_BUS_FMT_RGB888_1X7X4_SPWG,
 	.connector_type = DRM_MODE_CONNECTOR_LVDS,
 };
Signature · 1 line
2.43.0
maintainer Reviewed-by on v1 1/1
#1 lore raw
Quoted 22 lines · Fabio Estevam

From: Fabio Estevam <[email protected]>

The RFF500F-AWH-DNN datasheet requires a minimum delay of 250 ms between display signal output and backlight power-on.

Without this delay, the backlight can expose unsettled panel contents during display startup, resulting in a brief bright flash.

Set the panel enable delay to the datasheet-specified minimum.

Cc [email protected]
Fixes 1b2a9ec82099 ("drm/panel: simple: Add Raystar RFF500F-AWH-DNN panel entry")
Signed-off-by Fabio Estevam <[email protected]>
---
  drivers/gpu/drm/panel/panel-simple.c | 3 +++
  1 file changed, 3 insertions(+)
drivers/gpu/drm/panel/panel-simple.c +0 -0
index c95964ba25a9..70e37ff12c9e 100644

drivers/gpu/drm/panel/panel-simple.c static const struct panel_desc raystar_rff500f_awh_dnn = { · line 4362

Quoted 9 lines
drivers/gpu/drm/panel/panel-simple.c +3 -0
@@ -4354,6 +4354,9 @@ static const struct panel_desc raystar_rff500f_awh_dnn = {
  		.width = 108,
  		.height = 65,
  	},
+	.delay = {
+		.enable = 250,
+	},
  	.bus_format = MEDIA_BUS_FMT_RGB888_1X7X4_SPWG,
  	.connector_type = DRM_MODE_CONNECTOR_LVDS,
  };
Reviewed-by Neil Armstrong <[email protected]>

Thanks,
Neil

maintainer Applied
#2 lore raw
In reply to Fabio Estevam

Hi,

Quoted 9 lines · Fabio Estevam

The RFF500F-AWH-DNN datasheet requires a minimum delay of 250 ms between display signal output and backlight power-on.

Without this delay, the backlight can expose unsettled panel contents during display startup, resulting in a brief bright flash.

Set the panel enable delay to the datasheet-specified minimum.

[...]

Thanks, Applied to https://gitlab.freedesktop.org/drm/misc/kernel.git (drm-misc-next)

[1/1] drm/panel: simple: Add Raystar RFF500F-AWH-DNN enable delay

      https://gitlab.freedesktop.org/drm/misc/kernel/-/commit/a92ed345422cd66329b5e9d4e82b0452e185f36f
Signature · 1 line
Neil