drm/panel-simple: Fix inverted V/H SYNC for Frida FRD350H54004 panel

[ Upstream commit bad20a2dbfdfaf01560026909506b6ed69d65ba2 ]

The FRD350H54004 panel was marked as having active-high VSYNC and HSYNC
signals, which sorts-of worked, but resulted in the picture fading out
under certain circumstances.

Fix this issue by marking VSYNC and HSYNC signals active-low.

v2: Rebase on drm-misc-next

Fixes: 7b6bd8433609 ("drm/panel: simple: Add support for the Frida FRD350H54004 panel")
Cc: stable@vger.kernel.org # v5.5
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200716125647.10964-1-paul@crapouillou.net
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/gpu/drm/panel/panel-simple.c b/drivers/gpu/drm/panel/panel-simple.c
index 346e3f9fd505ab0bcb9a629fc64e794f8925fc0e..a68eff1fb4297f73b7acc8611617f340772e26ca 100644 (file)
--- a/drivers/gpu/drm/panel/panel-simple.c
+++ b/drivers/gpu/drm/panel/panel-simple.c
@@ -1537,7 +1537,7 @@ static const struct drm_display_mode frida_frd350h54004_mode = {
        .vsync_end = 240 + 2 + 6,
        .vtotal = 240 + 2 + 6 + 2,
        .vrefresh = 60,
-       .flags = DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_PVSYNC,
+       .flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC,
 };
 
 static const struct panel_desc frida_frd350h54004 = {