[PATCH v2 3/4] drm: panel: simple: Drop drive/sample bus flags for LVDS panels

[Laurent Pinchart]

The DRM bus flags reporting on which clock edge the pixel data and sync
signals are sampled or driven don't make sense for LVDS panels, as the
bus then uses sub-clock timings to send data. Drop those flags and add a
warning in the probe function to make sure the mistake won't be
repeated.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas at ideasonboard.com>
---
Changes since v1:

- White list flags instead of black listing them
---
 drivers/gpu/drm/panel/panel-simple.c | 28 +++++++++++++++++-----------
 1 file changed, 17 insertions(+), 11 deletions(-)

diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c
index c659d8262e5c..cd416376bf71 100644
--- a/drivers/gpu/drm/panel/panel-simple.c
+++ b/drivers/gpu/drm/panel/panel-simple.c
@@ -549,6 +549,14 @@ static int panel_simple_probe(struct device *dev, const struct panel_desc *desc)
 			panel_simple_parse_panel_timing_node(dev, panel, &dt);
 	}
 
+	if (desc->connector_type == DRM_MODE_CONNECTOR_LVDS)
+		/* Catch common mistakes for LVDS panels. */
+		WARN_ON(desc->bus_flags &
+			~(DRM_BUS_FLAG_DE_LOW |
+			  DRM_BUS_FLAG_DE_HIGH |
+			  DRM_BUS_FLAG_DATA_MSB_TO_LSB |
+			  DRM_BUS_FLAG_DATA_LSB_TO_MSB));
+
 	drm_panel_init(&panel->base, dev, &panel_simple_funcs,
 		       desc->connector_type);
 
@@ -688,7 +696,7 @@ static const struct panel_desc auo_b101aw03 = {
 		.height = 125,
 	},
 	.bus_format = MEDIA_BUS_FMT_RGB666_1X7X3_SPWG,
-	.bus_flags = DRM_BUS_FLAG_DE_HIGH | DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE,
+	.bus_flags = DRM_BUS_FLAG_DE_HIGH,
 	.connector_type = DRM_MODE_CONNECTOR_LVDS,
 };
 
@@ -1398,7 +1406,7 @@ static const struct panel_desc chunghwa_claa070wp03xg = {
 		.height = 150,
 	},
 	.bus_format = MEDIA_BUS_FMT_RGB666_1X7X3_SPWG,
-	.bus_flags = DRM_BUS_FLAG_DE_HIGH | DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE,
+	.bus_flags = DRM_BUS_FLAG_DE_HIGH,
 	.connector_type = DRM_MODE_CONNECTOR_LVDS,
 };
 
@@ -1423,7 +1431,7 @@ static const struct panel_desc chunghwa_claa101wa01a = {
 		.height = 120,
 	},
 	.bus_format = MEDIA_BUS_FMT_RGB666_1X7X3_SPWG,
-	.bus_flags = DRM_BUS_FLAG_DE_HIGH | DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE,
+	.bus_flags = DRM_BUS_FLAG_DE_HIGH,
 	.connector_type = DRM_MODE_CONNECTOR_LVDS,
 };
 
@@ -1448,7 +1456,7 @@ static const struct panel_desc chunghwa_claa101wb01 = {
 		.height = 125,
 	},
 	.bus_format = MEDIA_BUS_FMT_RGB666_1X7X3_SPWG,
-	.bus_flags = DRM_BUS_FLAG_DE_HIGH | DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE,
+	.bus_flags = DRM_BUS_FLAG_DE_HIGH,
 	.connector_type = DRM_MODE_CONNECTOR_LVDS,
 };
 
@@ -2123,7 +2131,7 @@ static const struct panel_desc innolux_n156bge_l21 = {
 		.height = 193,
 	},
 	.bus_format = MEDIA_BUS_FMT_RGB666_1X7X3_SPWG,
-	.bus_flags = DRM_BUS_FLAG_DE_HIGH | DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE,
+	.bus_flags = DRM_BUS_FLAG_DE_HIGH,
 	.connector_type = DRM_MODE_CONNECTOR_LVDS,
 };
 
@@ -2256,7 +2264,7 @@ static const struct panel_desc koe_tx26d202vm0bwa = {
 		.disable = 1000,
 	},
 	.bus_format = MEDIA_BUS_FMT_RGB888_1X7X4_SPWG,
-	.bus_flags = DRM_BUS_FLAG_DE_HIGH | DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE,
+	.bus_flags = DRM_BUS_FLAG_DE_HIGH,
 	.connector_type = DRM_MODE_CONNECTOR_LVDS,
 };
 
@@ -2497,9 +2505,7 @@ static const struct panel_desc logictechno_lt170410_2whc = {
 		.height = 136,
 	},
 	.bus_format = MEDIA_BUS_FMT_RGB888_1X7X4_SPWG,
-	.bus_flags = DRM_BUS_FLAG_DE_HIGH |
-		     DRM_BUS_FLAG_PIXDATA_SAMPLE_NEGEDGE |
-		     DRM_BUS_FLAG_SYNC_SAMPLE_NEGEDGE,
+	.bus_flags = DRM_BUS_FLAG_DE_HIGH,
 	.connector_type = DRM_MODE_CONNECTOR_LVDS,
 };
 
@@ -3072,7 +3078,7 @@ static const struct panel_desc samsung_ltn101nt05 = {
 		.height = 125,
 	},
 	.bus_format = MEDIA_BUS_FMT_RGB666_1X7X3_SPWG,
-	.bus_flags = DRM_BUS_FLAG_DE_HIGH | DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE,
+	.bus_flags = DRM_BUS_FLAG_DE_HIGH,
 	.connector_type = DRM_MODE_CONNECTOR_LVDS,
 };
 
@@ -3512,7 +3518,7 @@ static const struct panel_desc toshiba_lt089ac29000 = {
 		.height = 116,
 	},
 	.bus_format = MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA,
-	.bus_flags = DRM_BUS_FLAG_DE_HIGH | DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE,
+	.bus_flags = DRM_BUS_FLAG_DE_HIGH,
 	.connector_type = DRM_MODE_CONNECTOR_LVDS,
 };
 
-- 
Regards,

Laurent Pinchart