[PATCH 3.19 048/177] drm/radeon/dp: Set EDP_CONFIGURATION_SET for bridge chips if necessary

Greg Kroah-Hartman
2015-03-16T14:12:47Z

From: Alex Deucher <alexander.deucher@amd.com>

commit 66c2b84ba6256bc5399eed45582af9ebb3ba2c15 upstream.

Don't restrict it to just eDP panels. Some LVDS bridge chips require
this. Fixes blank panels on resume on certain laptops. Noticed
by mrnuke on IRC.

bug:
https://bugs.freedesktop.org/show_bug.cgi?id=42960

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/gpu/drm/radeon/atombios_dp.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)

--- a/drivers/gpu/drm/radeon/atombios_dp.c
+++ b/drivers/gpu/drm/radeon/atombios_dp.c
@@ -623,10 +623,8 @@ static int radeon_dp_link_train_init(str
drm_dp_dpcd_writeb(dp_info->aux,
DP_DOWNSPREAD_CTRL, 0);

- if ((dp_info->connector->connector_type == DRM_MODE_CONNECTOR_eDP) &&
- (dig->panel_mode == DP_PANEL_MODE_INTERNAL_DP2_MODE)) {
+ if (dig->panel_mode == DP_PANEL_MODE_INTERNAL_DP2_MODE)
drm_dp_dpcd_writeb(dp_info->aux, DP_EDP_CONFIGURATION_SET, 1);
- }

/* set the lane count on the sink */
tmp = dp_info->dp_lane_count;