openwrt/target/linux/layerscape/patches-5.4/805-display-0053-LF-323-2-d...

37 lines
1.3 KiB
Diff

From 06b758a32bb5ca164cff60f20173ecd71508c5ae Mon Sep 17 00:00:00 2001
From: Sandor Yu <Sandor.yu@nxp.com>
Date: Mon, 9 Dec 2019 17:58:29 +0800
Subject: [PATCH] LF-323-2: drm/bridge/cdns: enhance link training stability
Remove drm_dp_link_power_down from bridge_disable function,
in case some DP sinks aren't follow DP 1.1 specification
and can not exit the power saving state within 1 ms.
Add drm_dp_link_power_up to bridge_enable function,
make sure DP sinks are power up before link training.
Signed-off-by: Sandor Yu <Sandor.yu@nxp.com>
Reviewed-by: Robby Cai <robby.cai@nxp.com>
---
drivers/gpu/drm/bridge/cadence/cdns-dp-core.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/gpu/drm/bridge/cadence/cdns-dp-core.c
+++ b/drivers/gpu/drm/bridge/cadence/cdns-dp-core.c
@@ -329,6 +329,8 @@ static void cdn_hdp_bridge_enable(struct
struct cdns_mhdp_device *mhdp = bridge->driver_private;
int ret;
+ drm_dp_link_power_up(&mhdp->dp.aux, &mhdp->dp.link);
+
/* Link trainning */
ret = cdns_mhdp_train_link(mhdp);
if (ret) {
@@ -348,7 +350,6 @@ static void cdn_hdp_bridge_disable(struc
struct cdns_mhdp_device *mhdp = bridge->driver_private;
cdns_mhdp_set_video_status(mhdp, CONTROL_VIDEO_IDLE);
- drm_dp_link_power_down(&mhdp->dp.aux, &mhdp->dp.link);
}
static const struct drm_bridge_funcs cdns_dp_bridge_funcs = {