[RFC][PATCH] Revert "drm/panel-simple: drop use of data-mapping property"

[Christoph Niedermaier <cniedermaier@dh-electronics.com>]

Without the data-mapping devicetree property my display won't
work properly. It is flickering, because the bus flags won't
be assigned without a defined bus format by the imx parallel
display driver. There was a discussion about the removal [1]
and an agreement that a better solution is needed, but it is
missing so far. So what would be the better approach?

[1] https://patchwork.freedesktop.org/patch/357659/?series=74705&rev=1

This reverts commit d021d751c14752a0266865700f6f212fab40a18c.

Signed-off-by: Christoph Niedermaier <cniedermaier@dh-electronics.com>
Cc: Marek Vasut <marex@denx.de>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Maxime Ripard <mripard@kernel.org>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Pengutronix Kernel Team <kernel@pengutronix.de>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: NXP Linux Team <linux-imx@nxp.com>
Cc: linux-arm-kernel@lists.infradead.org
To: dri-devel@lists.freedesktop.org
---
 drivers/gpu/drm/panel/panel-simple.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c
index 3c08f9827acf..2c683d94a3f3 100644
--- a/drivers/gpu/drm/panel/panel-simple.c
+++ b/drivers/gpu/drm/panel/panel-simple.c
@@ -453,6 +453,7 @@ static int panel_dpi_probe(struct device *dev,
 	struct panel_desc *desc;
 	unsigned int bus_flags;
 	struct videomode vm;
+	const char *mapping;
 	int ret;
 
 	np = dev->of_node;
@@ -477,6 +478,16 @@ static int panel_dpi_probe(struct device *dev,
 	of_property_read_u32(np, "width-mm", &desc->size.width);
 	of_property_read_u32(np, "height-mm", &desc->size.height);
 
+	of_property_read_string(np, "data-mapping", &mapping);
+	if (!strcmp(mapping, "rgb24"))
+		desc->bus_format = MEDIA_BUS_FMT_RGB888_1X24;
+	else if (!strcmp(mapping, "rgb565"))
+		desc->bus_format = MEDIA_BUS_FMT_RGB565_1X16;
+	else if (!strcmp(mapping, "bgr666"))
+		desc->bus_format = MEDIA_BUS_FMT_RGB666_1X18;
+	else if (!strcmp(mapping, "lvds666"))
+		desc->bus_format = MEDIA_BUS_FMT_RGB666_1X24_CPADHI;
+
 	/* Extract bus_flags from display_timing */
 	bus_flags = 0;
 	vm.flags = timing->flags;
-- 
2.11.0