drm/omap: panel-tpo-td028ttec1: Add note for incorrect sync drive edge

According to the datasheet of the panel, both data, DEN and sync signals
are expected to be driven on the falling edge of the DOTCLK.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
diff --git a/drivers/gpu/drm/omapdrm/displays/panel-tpo-td028ttec1.c b/drivers/gpu/drm/omapdrm/displays/panel-tpo-td028ttec1.c
index c003f4d..f313dbf 100644
--- a/drivers/gpu/drm/omapdrm/displays/panel-tpo-td028ttec1.c
+++ b/drivers/gpu/drm/omapdrm/displays/panel-tpo-td028ttec1.c
@@ -56,6 +56,10 @@ static struct videomode td028ttec1_panel_vm = {
 	.flags		= DISPLAY_FLAGS_HSYNC_LOW | DISPLAY_FLAGS_VSYNC_LOW |
 			  DISPLAY_FLAGS_DE_HIGH | DISPLAY_FLAGS_SYNC_POSEDGE |
 			  DISPLAY_FLAGS_PIXDATA_NEGEDGE,
+	/*
+	 * Note: According to the panel documentation:
+	 * SYNC needs to be driven on the FALLING edge
+	 */
 };
 
 #define JBT_COMMAND	0x000