[PATCH] drm/panel/boe-tv101wum-nl6: set MIPI_DSI_MODE_LPM after sending panel disable cmds

[Brady Norander <brady.norander@mainlining.org>]

A recent change to Mediatek drm driver enabled HS mode support. With that
change, my MT8183-based krane sku176 chromebook display's colors would look darker
and desaturated after turning the display off and back on. Looking at other panel
drivers, it seems common to enable HS mode to send the disable commands and to
disable HS mode afterwards. However, the boe-tv101wum-nl6 driver would never
disable HS mode, leading to this issue. Update the behavior of boe_panel_disable
to match those other panel drivers. As a side note, I did also test removing the
line which enables HS mode during panel_disable. This worked fine for my device,
but just in case that doesn't work for other devices, I chose to keep that and
instead disable HS mode after sending the panel disable commands.

Signed-off-by: Brady Norander <brady.norander@mainlining.org>

diff --git a/drivers/gpu/drm/panel/panel-boe-tv101wum-nl6.c b/drivers/gpu/drm/panel/panel-boe-tv101wum-nl6.c
index d5fe105bdbdd..f69b5bd776c0 100644
--- a/drivers/gpu/drm/panel/panel-boe-tv101wum-nl6.c
+++ b/drivers/gpu/drm/panel/panel-boe-tv101wum-nl6.c
@@ -1326,6 +1326,8 @@ static int boe_panel_disable(struct drm_panel *panel)
 
 	mipi_dsi_msleep(&ctx, 150);
 
+	boe->dsi->mode_flags |= MIPI_DSI_MODE_LPM;
+
 	return ctx.accum_err;
 }
 
-- 
2.52.0