disp: msm: dp: skip waits when processing usb disconnect in sim mode

With real DP over Type-C sinks, DP driver requests access to USB
combo PHY from USB driver. But in DP SIM mode, there is no real
sink and PD management, so the combo PHY is managed by USB driver
and DP driver uses it without actually claiming it. If the USB
cable is unplugged in this scenario, USB driver notifies the
disconnection through an atomic notifier call. It does not expect
the handler to go into sleep, but the disconnect handler inside
DP driver has multiple wait for events and also sleeps to wait for
HW state updates.

This change passes a skip_wait flag to all the disable functions
to complete disconnect processing by skipping all processor sleeps
and event waits.

Change-Id: Ia98de0e7fa6b0573e644615ee59015914a93f4cf
Signed-off-by: Rajkumar Subbiah <[email protected]>

msm/dp/dp_audio.c

@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0-only
 /*
+ * Copyright (c) 2022, Qualcomm Innovation Center, Inc. All rights reserved.
  * Copyright (c) 2016-2021, The Linux Foundation. All rights reserved.
  */
 
@@ -769,7 +770,7 @@ end:
 	return rc;
 }
 
-static int dp_audio_off(struct dp_audio *dp_audio)
+static int dp_audio_off(struct dp_audio *dp_audio, bool skip_wait)
 {
 	int rc = 0;
 	struct dp_audio_private *audio;
@@ -794,9 +795,11 @@ static int dp_audio_off(struct dp_audio *dp_audio)
 	if (work_pending)
 		DP_DEBUG("pending notification work completed\n");
 
-	rc = dp_audio_notify(audio, EXT_DISPLAY_CABLE_DISCONNECT);
-	if (rc)
-		goto end;
+	if (!skip_wait) {
+		rc = dp_audio_notify(audio, EXT_DISPLAY_CABLE_DISCONNECT);
+		if (rc)
+			goto end;
+	}
 
 	DP_DEBUG("success\n");
 end:

msm/dp/dp_audio.h

@@ -1,5 +1,6 @@
 /* SPDX-License-Identifier: GPL-2.0-only */
 /*
+ * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved.
  * Copyright (c) 2016-2020, The Linux Foundation. All rights reserved.
  */
 
@@ -41,10 +42,11 @@ struct dp_audio {
 	 * playback should be stopped on the external display.
 	 *
 	 * @dp_audio: an instance of struct dp_audio.
+	 * @skip_wait: flag to skip any waits
 	 *
 	 * Returns the error code in case of failure, 0 in success case.
 	 */
-	int (*off)(struct dp_audio *dp_audio);
+	int (*off)(struct dp_audio *dp_audio, bool skip_wait);
 };
 
 /**

msm/dp/dp_debug.c

@@ -2466,6 +2466,8 @@ static void dp_debug_abort(struct dp_debug *dp_debug)
 	debug = container_of(dp_debug, struct dp_debug_private, dp_debug);
 
 	mutex_lock(&debug->lock);
+	// disconnect has already been handled. so clear hotplug
+	debug->hotplug = false;
 	dp_debug_set_sim_mode(debug, false);
 	mutex_unlock(&debug->lock);
 }

msm/dp/dp_display.c

@@ -293,7 +293,7 @@ static void dp_audio_enable(struct dp_display_private *dp, bool enable)
 					dp->link->link_params.lane_count;
 				dp_panel->audio->on(dp_panel->audio);
 			} else {
-				dp_panel->audio->off(dp_panel->audio);
+				dp_panel->audio->off(dp_panel->audio, false);
 			}
 		}
 	}
@@ -917,7 +917,7 @@ static bool dp_display_send_hpd_event(struct dp_display_private *dp)
 	return true;
 }
 
-static int dp_display_send_hpd_notification(struct dp_display_private *dp)
+static int dp_display_send_hpd_notification(struct dp_display_private *dp, bool skip_wait)
 {
 	int ret = 0;
 	bool hpd = !!dp_display_state_is(DP_STATE_CONNECTED);
@@ -976,7 +976,7 @@ static int dp_display_send_hpd_notification(struct dp_display_private *dp)
 		goto skip_wait;
 	}
 
-	if (hpd && dp->mst.mst_active)
+	if (skip_wait || (hpd && dp->mst.mst_active))
 		goto skip_wait;
 
 	if (!dp->mst.mst_active &&
@@ -1321,7 +1321,7 @@ end:
 	}
 
 	if (!rc && !dp_display_state_is(DP_STATE_ABORTED))
-		dp_display_send_hpd_notification(dp);
+		dp_display_send_hpd_notification(dp, false);
 
 skip_notify:
 	SDE_EVT32_EXTERNAL(SDE_EVTLOG_FUNC_EXIT, dp->state,
@@ -1329,7 +1329,7 @@ skip_notify:
 	return rc;
 }
 
-static void dp_display_process_mst_hpd_low(struct dp_display_private *dp)
+static void dp_display_process_mst_hpd_low(struct dp_display_private *dp, bool skip_wait)
 {
 	int rc = 0;
 
@@ -1346,7 +1346,7 @@ static void dp_display_process_mst_hpd_low(struct dp_display_private *dp)
 
 		if ((dp_display_state_is(DP_STATE_CONNECT_NOTIFIED) ||
 				dp_display_state_is(DP_STATE_ENABLED)))
-			rc = dp_display_send_hpd_notification(dp);
+			rc = dp_display_send_hpd_notification(dp, skip_wait);
 
 		dp_display_set_mst_mgr_state(dp, false);
 		dp_display_update_mst_state(dp, false);
@@ -1355,7 +1355,7 @@ static void dp_display_process_mst_hpd_low(struct dp_display_private *dp)
 	DP_MST_DEBUG("mst_hpd_low. mst_active:%d\n", dp->mst.mst_active);
 }
 
-static int dp_display_process_hpd_low(struct dp_display_private *dp)
+static int dp_display_process_hpd_low(struct dp_display_private *dp, bool skip_wait)
 {
 	int rc = 0;
 
@@ -1364,11 +1364,11 @@ static int dp_display_process_hpd_low(struct dp_display_private *dp)
 	dp_audio_enable(dp, false);
 
 	if (dp->mst.mst_active) {
-		dp_display_process_mst_hpd_low(dp);
+		dp_display_process_mst_hpd_low(dp, skip_wait);
 	} else {
 		if ((dp_display_state_is(DP_STATE_CONNECT_NOTIFIED) ||
 				dp_display_state_is(DP_STATE_ENABLED)))
-			rc = dp_display_send_hpd_notification(dp);
+			rc = dp_display_send_hpd_notification(dp, skip_wait);
 	}
 
 	mutex_lock(&dp->session_lock);
@@ -1551,7 +1551,7 @@ static void dp_display_stream_disable(struct dp_display_private *dp,
 	dp->active_stream_cnt--;
 }
 
-static void dp_display_clean(struct dp_display_private *dp)
+static void dp_display_clean(struct dp_display_private *dp, bool skip_wait)
 {
 	int idx;
 	struct dp_panel *dp_panel;
@@ -1579,9 +1579,10 @@ static void dp_display_clean(struct dp_display_private *dp)
 
 		dp_panel = dp->active_panels[idx];
 		if (dp_panel->audio_supported)
-			dp_panel->audio->off(dp_panel->audio);
+			dp_panel->audio->off(dp_panel->audio, skip_wait);
 
-		dp_display_stream_pre_disable(dp, dp_panel);
+		if (!skip_wait)
+			dp_display_stream_pre_disable(dp, dp_panel);
 		dp_display_stream_disable(dp, dp_panel);
 		dp_display_clear_reservation(&dp->dp_display, dp_panel);
 		dp_panel->deinit(dp_panel, 0);
@@ -1593,12 +1594,12 @@ static void dp_display_clean(struct dp_display_private *dp)
 	SDE_EVT32_EXTERNAL(SDE_EVTLOG_FUNC_EXIT, dp->state);
 }
 
-static int dp_display_handle_disconnect(struct dp_display_private *dp)
+static int dp_display_handle_disconnect(struct dp_display_private *dp, bool skip_wait)
 {
 	int rc;
 
 	SDE_EVT32_EXTERNAL(SDE_EVTLOG_FUNC_ENTRY, dp->state);
-	rc = dp_display_process_hpd_low(dp);
+	rc = dp_display_process_hpd_low(dp, skip_wait);
 	if (rc) {
 		/* cancel any pending request */
 		dp->ctrl->abort(dp->ctrl, true);
@@ -1607,7 +1608,7 @@ static int dp_display_handle_disconnect(struct dp_display_private *dp)
 
 	mutex_lock(&dp->session_lock);
 	if (dp_display_state_is(DP_STATE_ENABLED))
-		dp_display_clean(dp);
+		dp_display_clean(dp, skip_wait);
 
 	dp_display_host_unready(dp);
 
@@ -1648,7 +1649,7 @@ static void dp_display_disconnect_sync(struct dp_display_private *dp)
 	DP_DEBUG("disconnect delay = %d ms\n", disconnect_delay_ms);
 	msleep(disconnect_delay_ms);
 
-	dp_display_handle_disconnect(dp);
+	dp_display_handle_disconnect(dp, false);
 	SDE_EVT32_EXTERNAL(SDE_EVTLOG_FUNC_EXIT, dp->state,
 		disconnect_delay_ms);
 }
@@ -1764,7 +1765,7 @@ static void dp_display_attention_work(struct work_struct *work)
 		SDE_EVT32_EXTERNAL(dp->state, DS_PORT_STATUS_CHANGED);
 		if (!dp->mst.mst_active) {
 			if (dp_display_is_sink_count_zero(dp)) {
-				dp_display_handle_disconnect(dp);
+				dp_display_handle_disconnect(dp, false);
 			} else {
 				/*
 				 * connect work should take care of sending
@@ -1779,7 +1780,7 @@ static void dp_display_attention_work(struct work_struct *work)
 
 	if (dp->link->sink_request & DP_TEST_LINK_VIDEO_PATTERN) {
 		SDE_EVT32_EXTERNAL(dp->state, DP_TEST_LINK_VIDEO_PATTERN);
-		dp_display_handle_disconnect(dp);
+		dp_display_handle_disconnect(dp, false);
 
 		dp->panel->video_test = true;
 		/*
@@ -1838,7 +1839,7 @@ cp_irq:
 		 * account for that. This is not needed if this
 		 * attention work was handling a test request
 		 */
-		dp_display_send_hpd_notification(dp);
+		dp_display_send_hpd_notification(dp, false);
 	}
 
 mst_attention:
@@ -1939,7 +1940,10 @@ static int dp_display_usb_notifier(struct notifier_block *nb,
 	SDE_EVT32_EXTERNAL(dp->state, dp->debug->sim_mode, action);
 	if (!action && dp->debug->sim_mode) {
 		DP_WARN("usb disconnected during simulation\n");
-		dp_display_disconnect_sync(dp);
+		dp_display_state_add(DP_STATE_ABORTED);
+		dp->ctrl->abort(dp->ctrl, true);
+		dp->aux->abort(dp->aux, true);
+		dp_display_handle_disconnect(dp, true);
 		dp->debug->abort(dp->debug);
 	}
 
@@ -1978,7 +1982,7 @@ int dp_display_mmrm_callback(struct mmrm_client_notifier_data *notifier_data)
 	if (notifier_data->cb_type == MMRM_CLIENT_RESOURCE_VALUE_CHANGE
 				&& dp_display_state_is(DP_STATE_ENABLED)
 				&& !dp_display_state_is(DP_STATE_ABORTED)) {
-		ret = dp_display_handle_disconnect(dp);
+		ret = dp_display_handle_disconnect(dp, false);
 		if (ret)
 			DP_ERR("mmrm callback error reducing clk, ret:%d\n", ret);
 	}
@@ -2650,7 +2654,7 @@ static int dp_display_pre_disable(struct dp_display *dp_display, void *panel)
 
 clean:
 	if (dp_panel->audio_supported)
-		dp_panel->audio->off(dp_panel->audio);
+		dp_panel->audio->off(dp_panel->audio, false);
 
 	rc = dp_display_stream_pre_disable(dp, dp_panel);