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From:   Douglas Anderson <dianders@chromium.org>
To:     dri-devel@lists.freedesktop.org
Cc:     linux-samsung-soc@vger.kernel.org,
        Hsin-Yi Wang <hsinyi@chromium.org>, matthias.bgg@gmail.com,
        linux-arm-kernel@lists.infradead.org,
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        <angelogioacchino.delregno@collabora.com>,
        devicetree@vger.kernel.org, linux-mediatek@lists.infradead.org,
        Marek Szyprowski <m.szyprowski@samsung.com>,
        Douglas Anderson <dianders@chromium.org>, airlied@gmail.com,
        daniel@ffwll.ch, jitao.shi@mediatek.com, linus.walleij@linaro.org,
        linux-kernel@vger.kernel.org, neil.armstrong@linaro.org,
        quic_jesszhan@quicinc.com, sam@ravnborg.org
Subject: [PATCH] drm/panel: Move AUX B116XW03 out of panel-edp back to panel-simple
Date:   Mon, 25 Sep 2023 15:00:11 -0700
Message-ID: <20230925150010.1.Iff672233861bcc4cf25a7ad0a81308adc3bda8a4@changeid>
MIME-Version: 1.0
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Precedence: bulk

In commit 5f04e7ce392d ("drm/panel-edp: Split eDP panels out of
panel-simple") I moved a pile of panels out of panel-simple driver
into the newly created panel-edp driver. One of those panels, however,
shouldn't have been moved.

As is clear from commit e35e305eff0f ("drm/panel: simple: Add AUO
B116XW03 panel support"), AUX B116XW03 is an LVDS panel. It's used in
exynos5250-snow and exynos5420-peach-pit where it's clear that the
panel is hooked up with LVDS. Furthermore, searching for datasheets I
found one that makes it clear that this panel is LVDS.

As far as I can tell, I got confused because in commit 88d3457ceb82
("drm/panel: auo,b116xw03: fix flash backlight when power on") Jitao
Shi added "DRM_MODE_CONNECTOR_eDP". That seems wrong. Looking at the
downstream ChromeOS trees, it seems like some Mediatek boards are
using a panel that they call "auo,b116xw03" that's an eDP panel. The
best I can guess is that they actually have a different panel that has
similar timing. If so then the proper panel should be used or they
should switch to the generic "edp-panel" compatible.

When moving this back to panel-edp, I wasn't sure what to use for
.bus_flags and .bus_format and whether to add the extra "enable" delay
from commit 88d3457ceb82 ("drm/panel: auo,b116xw03: fix flash
backlight when power on"). I've added formats/flags/delays based on my
(inexpert) analysis of the datasheet. These are untested.

NOTE: if/when this is backported to stable, we might run into some
trouble. Specifically, before 474c162878ba ("arm64: dts: mt8183:
jacuzzi: Move panel under aux-bus") this panel was used by
"mt8183-kukui-jacuzzi", which assumed it was an eDP panel. I don't
know what to suggest for that other than someone making up a bogus
panel for jacuzzi that's just for the stable channel.

Fixes: 88d3457ceb82 ("drm/panel: auo,b116xw03: fix flash backlight when power on")
Fixes: 5f04e7ce392d ("drm/panel-edp: Split eDP panels out of panel-simple")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
---
I haven't had a snow or peach-pit hooked up for debugging / testing
for years. I presume that they must be broken and hope that this fixes
them.

 drivers/gpu/drm/panel/panel-edp.c    | 29 -----------------------
 drivers/gpu/drm/panel/panel-simple.c | 35 ++++++++++++++++++++++++++++
 2 files changed, 35 insertions(+), 29 deletions(-)

diff --git a/drivers/gpu/drm/panel/panel-edp.c b/drivers/gpu/drm/panel/panel-edp.c
index feb665df35a1..95c8472d878a 100644
--- a/drivers/gpu/drm/panel/panel-edp.c
+++ b/drivers/gpu/drm/panel/panel-edp.c
@@ -976,32 +976,6 @@ static const struct panel_desc auo_b116xak01 = {
 	},
 };
 
-static const struct drm_display_mode auo_b116xw03_mode = {
-	.clock = 70589,
-	.hdisplay = 1366,
-	.hsync_start = 1366 + 40,
-	.hsync_end = 1366 + 40 + 40,
-	.htotal = 1366 + 40 + 40 + 32,
-	.vdisplay = 768,
-	.vsync_start = 768 + 10,
-	.vsync_end = 768 + 10 + 12,
-	.vtotal = 768 + 10 + 12 + 6,
-	.flags = DRM_MODE_FLAG_NVSYNC | DRM_MODE_FLAG_NHSYNC,
-};
-
-static const struct panel_desc auo_b116xw03 = {
-	.modes = &auo_b116xw03_mode,
-	.num_modes = 1,
-	.bpc = 6,
-	.size = {
-		.width = 256,
-		.height = 144,
-	},
-	.delay = {
-		.enable = 400,
-	},
-};
-
 static const struct drm_display_mode auo_b133han05_mode = {
 	.clock = 142600,
 	.hdisplay = 1920,
@@ -1725,9 +1699,6 @@ static const struct of_device_id platform_of_match[] = {
 	}, {
 		.compatible = "auo,b116xa01",
 		.data = &auo_b116xak01,
-	}, {
-		.compatible = "auo,b116xw03",
-		.data = &auo_b116xw03,
 	}, {
 		.compatible = "auo,b133han05",
 		.data = &auo_b133han05,
diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c
index bb89e6d047bc..439d26928938 100644
--- a/drivers/gpu/drm/panel/panel-simple.c
+++ b/drivers/gpu/drm/panel/panel-simple.c
@@ -919,6 +919,38 @@ static const struct panel_desc auo_b101xtn01 = {
 	},
 };
 
+static const struct drm_display_mode auo_b116xw03_mode = {
+	.clock = 70589,
+	.hdisplay = 1366,
+	.hsync_start = 1366 + 40,
+	.hsync_end = 1366 + 40 + 40,
+	.htotal = 1366 + 40 + 40 + 32,
+	.vdisplay = 768,
+	.vsync_start = 768 + 10,
+	.vsync_end = 768 + 10 + 12,
+	.vtotal = 768 + 10 + 12 + 6,
+	.flags = DRM_MODE_FLAG_NVSYNC | DRM_MODE_FLAG_NHSYNC,
+};
+
+static const struct panel_desc auo_b116xw03 = {
+	.modes = &auo_b116xw03_mode,
+	.num_modes = 1,
+	.bpc = 6,
+	.size = {
+		.width = 256,
+		.height = 144,
+	},
+	.delay = {
+		.prepare = 1,
+		.enable = 200,
+		.disable = 200,
+		.unprepare = 500,
+	},
+	.bus_format = MEDIA_BUS_FMT_RGB666_1X7X3_SPWG,
+	.bus_flags = DRM_BUS_FLAG_DE_HIGH,
+	.connector_type = DRM_MODE_CONNECTOR_LVDS,
+};
+
 static const struct display_timing auo_g070vvn01_timings = {
 	.pixelclock = { 33300000, 34209000, 45000000 },
 	.hactive = { 800, 800, 800 },
@@ -4128,6 +4160,9 @@ static const struct of_device_id platform_of_match[] = {
 	}, {
 		.compatible = "auo,b101xtn01",
 		.data = &auo_b101xtn01,
+	}, {
+		.compatible = "auo,b116xw03",
+		.data = &auo_b116xw03,
 	}, {
 		.compatible = "auo,g070vvn01",
 		.data = &auo_g070vvn01,
-- 
2.42.0.515.g380fc7ccd1-goog