[PATCH RESEND v5 13/25] drm/msm/dp: replace power_on with active_stream_cnt for dp_display

[Yongxing Mou]

From: Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx>

For DP MST, the link clock and power domain resources stay on until
both streams have been disabled OR we receive hotplug. Introduce an
active_stream_cnt to track the number of active streams and necessary
state handling. Replace the power_on variable with active_stream_cnt
as power_on boolean works only for a single stream.

Signed-off-by: Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx>
Signed-off-by: Yongxing Mou <yongxing.mou@xxxxxxxxxxxxxxxx>
---
 drivers/gpu/drm/msm/dp/dp_audio.c   |  2 +-
 drivers/gpu/drm/msm/dp/dp_display.c | 28 +++++++++++++++++-----------
 drivers/gpu/drm/msm/dp/dp_display.h |  2 +-
 3 files changed, 19 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/msm/dp/dp_audio.c b/drivers/gpu/drm/msm/dp/dp_audio.c
index 41018e82efa1..035e230201fd 100644
--- a/drivers/gpu/drm/msm/dp/dp_audio.c
+++ b/drivers/gpu/drm/msm/dp/dp_audio.c
@@ -284,7 +284,7 @@ int msm_dp_audio_prepare(struct drm_bridge *bridge,
 	 * such cases check for connection status and bail out if not
 	 * connected.
 	 */
-	if (!msm_dp_display->power_on) {
+	if (!msm_dp_display->active_stream_cnt) {
 		rc = -EINVAL;
 		goto end;
 	}
diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
index 0e432f35cc51..d0081ea9f5cd 100644
--- a/drivers/gpu/drm/msm/dp/dp_display.c
+++ b/drivers/gpu/drm/msm/dp/dp_display.c
@@ -650,7 +650,7 @@ int msm_dp_display_prepare_link(struct msm_dp *msm_dp_display)
 	if (dp->link->sink_count == 0)
 		return rc;
 
-	if (!msm_dp_display->power_on) {
+	if (!msm_dp_display->active_stream_cnt) {
 		msm_dp_display_host_phy_init(dp);
 		force_link_train = true;
 	}
@@ -670,14 +670,10 @@ static int msm_dp_display_enable(struct msm_dp_display_private *dp,
 	struct msm_dp *msm_dp_display = &dp->msm_dp_display;
 
 	drm_dbg_dp(dp->drm_dev, "sink_count=%d\n", dp->link->sink_count);
-	if (msm_dp_display->power_on) {
-		drm_dbg_dp(dp->drm_dev, "Link already setup, return\n");
-		return 0;
-	}
 
 	rc = msm_dp_ctrl_on_stream(dp->ctrl, msm_dp_panel, msm_dp_display->mst_active);
-	if (!rc)
-		msm_dp_display->power_on = true;
+
+	msm_dp_display->active_stream_cnt++;
 
 	return rc;
 }
@@ -726,14 +722,14 @@ static int msm_dp_display_disable(struct msm_dp_display_private *dp,
 {
 	struct msm_dp *msm_dp_display = &dp->msm_dp_display;
 
-	if (!msm_dp_display->power_on)
+	if (!msm_dp_display->active_stream_cnt)
 		return 0;
 
 	msm_dp_panel_disable_vsc_sdp(msm_dp_panel);
 
 	msm_dp_ctrl_off_pixel_clk(dp->ctrl, msm_dp_panel->stream_id);
 
-	msm_dp_display->power_on = false;
+	msm_dp_display->active_stream_cnt--;
 
 	drm_dbg_dp(dp->drm_dev, "sink count: %d\n", dp->link->sink_count);
 	return 0;
@@ -850,10 +846,10 @@ void msm_dp_snapshot(struct msm_disp_state *disp_state, struct msm_dp *dp)
 	 * if we are reading registers we need the link clocks to be on
 	 * however till DP cable is connected this will not happen as we
 	 * do not know the resolution to power up with. Hence check the
-	 * power_on status before dumping DP registers to avoid crash due
+	 * active_stream_cnt status before dumping DP registers to avoid crash due
 	 * to unclocked access
 	 */
-	if (!dp->power_on)
+	if (!dp->active_stream_cnt)
 		return;
 
 	msm_disp_snapshot_add_block(disp_state, msm_dp_display->ahb_len,
@@ -1535,6 +1531,11 @@ void msm_dp_display_disable_helper(struct msm_dp *msm_dp_display,
 
 	dp = container_of(msm_dp_display, struct msm_dp_display_private, msm_dp_display);
 
+	if (!msm_dp_display->active_stream_cnt) {
+		drm_dbg_dp(dp->drm_dev, "no active streams\n");
+		return;
+	}
+
 	msm_dp_ctrl_push_vcpf(dp->ctrl, msm_dp_panel);
 	msm_dp_ctrl_mst_stream_channel_slot_setup(dp->ctrl);
 	msm_dp_ctrl_mst_send_act(dp->ctrl, msm_dp_panel);
@@ -1555,6 +1556,11 @@ void msm_dp_display_unprepare(struct msm_dp *msm_dp_display)
 
 	dp = container_of(msm_dp_display, struct msm_dp_display_private, msm_dp_display);
 
+	if (msm_dp_display->active_stream_cnt) {
+		drm_dbg_dp(dp->drm_dev, "stream still active, return\n");
+		return;
+	}
+
 	/* dongle is still connected but sinks are disconnected */
 	if (dp->link->sink_count == 0)
 		msm_dp_link_psm_config(dp->link, &dp->panel->link_info, true);
diff --git a/drivers/gpu/drm/msm/dp/dp_display.h b/drivers/gpu/drm/msm/dp/dp_display.h
index 55ffa22bb233..75dc40261723 100644
--- a/drivers/gpu/drm/msm/dp/dp_display.h
+++ b/drivers/gpu/drm/msm/dp/dp_display.h
@@ -18,7 +18,7 @@ struct msm_dp {
 	struct drm_bridge *next_bridge;
 	struct drm_bridge *bridge;
 	bool audio_enabled;
-	bool power_on;
+	u32 active_stream_cnt;
 	bool mst_active;
 	unsigned int connector_type;
 	bool is_edp;

-- 
2.43.0