drm/msm/dp: initialize audio_comp when audio starts

Initialize audio_comp when audio starts and wait for audio_comp at
dp_display_disable(). This will take care of both dongle unplugged
and display off (suspend) cases.

Changes in v2:
-- add dp_display_signal_audio_start()

Changes in v3:
-- restore dp_display_handle_plugged_change() at dp_hpd_unplug_handle().

Changes in v4:
-- none

Signed-off-by: Kuogee Hsieh <khsieh@codeaurora.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Tested-by: Stephen Boyd <swboyd@chromium.org>
Fixes: c703d57 ("drm/msm/dp: trigger unplug event in msm_dp_display_disable")
Link: https://lore.kernel.org/r/1619048258-8717-3-git-send-email-khsieh@codeaurora.org
Signed-off-by: Rob Clark <robdclark@chromium.org>

Author: Kuogee Hsieh

drivers/gpu/drm/msm/dp/dp_audio.c

@@ -527,6 +527,7 @@ int dp_audio_hw_params(struct device *dev,
 	dp_audio_setup_acr(audio);
 	dp_audio_safe_to_exit_level(audio);
 	dp_audio_enable(audio, true);
+	dp_display_signal_audio_start(dp_display);
 	dp_display->audio_enabled = true;
 
 end:

drivers/gpu/drm/msm/dp/dp_display.c

@@ -178,6 +178,15 @@ static int dp_del_event(struct dp_display_private *dp_priv, u32 event)
 	return 0;
 }
 
+void dp_display_signal_audio_start(struct msm_dp *dp_display)
+{
+	struct dp_display_private *dp;
+
+	dp = container_of(dp_display, struct dp_display_private, dp_display);
+
+	reinit_completion(&dp->audio_comp);
+}
+
 void dp_display_signal_audio_complete(struct msm_dp *dp_display)
 {
 	struct dp_display_private *dp;
@@ -649,7 +658,6 @@ static int dp_hpd_unplug_handle(struct dp_display_private *dp, u32 data)
 	dp_add_event(dp, EV_DISCONNECT_PENDING_TIMEOUT, 0, DP_TIMEOUT_5_SECOND);
 
 	/* signal the disconnect event early to ensure proper teardown */
-	reinit_completion(&dp->audio_comp);
 	dp_display_handle_plugged_change(g_dp_display, false);
 
 	dp_catalog_hpd_config_intr(dp->catalog, DP_DP_HPD_PLUG_INT_MASK |
@@ -894,7 +902,6 @@ static int dp_display_disable(struct dp_display_private *dp, u32 data)
 	/* wait only if audio was enabled */
 	if (dp_display->audio_enabled) {
 		/* signal the disconnect event */
-		reinit_completion(&dp->audio_comp);
 		dp_display_handle_plugged_change(dp_display, false);
 		if (!wait_for_completion_timeout(&dp->audio_comp,
 				HZ * 5))

drivers/gpu/drm/msm/dp/dp_display.h

@@ -34,6 +34,7 @@ int dp_display_get_modes(struct msm_dp *dp_display,
 int dp_display_request_irq(struct msm_dp *dp_display);
 bool dp_display_check_video_test(struct msm_dp *dp_display);
 int dp_display_get_test_bpp(struct msm_dp *dp_display);
+void dp_display_signal_audio_start(struct msm_dp *dp_display);
 void dp_display_signal_audio_complete(struct msm_dp *dp_display);
 
 #endif /* _DP_DISPLAY_H_ */