0013-drm-panel-simple-Add-a-timing-for-the-Raspberry-Pi-7.patch

From 7d5a7b1ffb255c6822f6dfa5b605a2778ac99622 Mon Sep 17 00:00:00 2001
From: Mattias Walström <lazzer@gmail.com>
Date: Wed, 20 Aug 2025 21:38:24 +0200
Subject: [PATCH 13/33] drm/panel-simple: Add a timing for the Raspberry Pi 7"
 panel

The Raspberry Pi 7" 800x480 panel uses a Toshiba TC358762 DSI
to DPI bridge chip, so there is a requirement for the timings
to be specified for the end panel. Add such a definition.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>

drm/panel: simple: Alter the timing for the Pi 7" DSI display

vc4 has always fixed up the timing, so the values defined have
never actually appeared on the wire.
The display appears to want a slightly longer HFP, so extend
the timings and recompute the clock to give the same frame rate.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>

drm/panel-simple: Fix 7inch panel mode for misalignment

The 7inch panel is one line off the screen both horizontally
and vertically.

Alter the panel mode to correct this.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>

drm/panel-simple: Increase pixel clock on Pi 7inch panel

The Toshiba bridge is very fussy and doesn't like the CM3
output when being told to produce a 27.777MHz pixel clock, which
is an almost perfect match to the DSI link integer divider.

Increasing to 30MHz will switch the DSI link from 333MHz to 400MHz
and makes the bridge happy with the same video timing as works
on Pi4.
(Pi4 will be using a link frequency of 375MHz due to a 3GHz
parent PLL).

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
---
 drivers/gpu/drm/panel/panel-simple.c | 31 +++++++++++++++++++++++++++-
 1 file changed, 30 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c
index 271f93399193..75dbc3cb8135 100644
--- a/drivers/gpu/drm/panel/panel-simple.c
+++ b/drivers/gpu/drm/panel/panel-simple.c
@@ -400,7 +400,8 @@ static int panel_simple_get_modes(struct drm_panel *panel,
 	 * TODO: Remove once all drm drivers call
 	 * drm_connector_set_orientation_from_panel()
 	 */
-	drm_connector_set_panel_orientation(connector, p->orientation);
+	/* RPI Hack */
+	//drm_connector_set_panel_orientation(connector, p->orientation);
 
 	return num;
 }
@@ -4074,6 +4075,31 @@ static const struct panel_desc qishenglong_gopher2b_lcd = {
 	.connector_type = DRM_MODE_CONNECTOR_DPI,
 };
 
+static const struct drm_display_mode raspberrypi_7inch_mode = {
+       .clock = 30000,
+       .hdisplay = 800,
+       .hsync_start = 800 + 131,
+       .hsync_end = 800 + 131 + 2,
+       .htotal = 800 + 131 + 2 + 45,
+       .vdisplay = 480,
+       .vsync_start = 480 + 7,
+       .vsync_end = 480 + 7 + 2,
+       .vtotal = 480 + 7 + 2 + 22,
+       .flags = DRM_MODE_FLAG_NVSYNC | DRM_MODE_FLAG_NHSYNC,
+};
+
+static const struct panel_desc raspberrypi_7inch = {
+       .modes = &raspberrypi_7inch_mode,
+       .num_modes = 1,
+       .bpc = 8,
+       .size = {
+               .width = 154,
+               .height = 86,
+       },
+       .bus_format = MEDIA_BUS_FMT_RGB888_1X24,
+       .connector_type = DRM_MODE_CONNECTOR_DSI,
+};
+
 static const struct display_timing rocktech_rk043fn48h_timing = {
 	.pixelclock = { 6000000, 9000000, 12000000 },
 	.hactive = { 480, 480, 480 },
@@ -5344,6 +5370,9 @@ static const struct of_device_id platform_of_match[] = {
 		.compatible = "qishenglong,gopher2b-lcd",
 		.data = &qishenglong_gopher2b_lcd,
 	}, {
+               .compatible = "raspberrypi,7inch-dsi",
+               .data = &raspberrypi_7inch,
+        }, {
 		.compatible = "rocktech,rk043fn48h",
 		.data = &rocktech_rk043fn48h,
 	}, {