[PATCH 33/45] drm/msm/dp: add irq hpd callback for dp mst

[Abhinav Kumar]

Add irq hpd callback for the dp mst module which shall be
invoked from the dp_display's irq hpd handler to perform
mst specific operations in case of irq hpd. In MST case, route
the IRQ HPD messages to MST module.

Signed-off-by: Abhinav Kumar <quic_abhinavk at quicinc.com>
---
 drivers/gpu/drm/msm/dp/dp_display.c | 17 +++++++++++++----
 drivers/gpu/drm/msm/dp/dp_mst_drm.c | 36 +++++++++++++++++++++++++++++++++++-
 drivers/gpu/drm/msm/dp/dp_mst_drm.h |  2 ++
 3 files changed, 50 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
index 60316633cc6bcfdfad8ab356d803642d353add61..97f8228042773f51f23a9d39fc009de0798059d7 100644
--- a/drivers/gpu/drm/msm/dp/dp_display.c
+++ b/drivers/gpu/drm/msm/dp/dp_display.c
@@ -583,7 +583,9 @@ static int msm_dp_display_usbpd_attention_cb(struct device *dev)
 {
 	int rc = 0;
 	u32 sink_request;
+
 	struct msm_dp_display_private *dp = dev_get_dp_display_private(dev);
+	struct msm_dp *msm_dp_display = &dp->msm_dp_display;
 
 	/* check for any test request issued by sink */
 	rc = msm_dp_link_process_request(dp->link);
@@ -591,12 +593,18 @@ static int msm_dp_display_usbpd_attention_cb(struct device *dev)
 		sink_request = dp->link->sink_request;
 		drm_dbg_dp(dp->drm_dev, "hpd_state=%d sink_request=%d\n",
 					dp->hpd_state, sink_request);
-		if (sink_request & DS_PORT_STATUS_CHANGED)
-			rc = msm_dp_display_handle_port_status_changed(dp);
-		else
+		if (sink_request & DS_PORT_STATUS_CHANGED) {
+			if (!msm_dp_display->mst_active)
+				rc = msm_dp_display_handle_port_status_changed(dp);
+		} else {
 			rc = msm_dp_display_handle_irq_hpd(dp);
+		}
 	}
 
+	/* let MST specific IRQ events be handled by its callback */
+	if (msm_dp_display->mst_active)
+		msm_dp_mst_display_hpd_irq(&dp->msm_dp_display);
+
 	return rc;
 }
 
@@ -736,7 +744,8 @@ static int msm_dp_irq_hpd_handle(struct msm_dp_display_private *dp, u32 data)
 	drm_dbg_dp(dp->drm_dev, "Before, type=%d hpd_state=%d\n",
 			dp->msm_dp_display.connector_type, state);
 
-	if (state == ST_MAINLINK_READY || state == ST_DISCONNECT_PENDING) {
+	if ((state == ST_MAINLINK_READY || state == ST_DISCONNECT_PENDING) &&
+	    !dp->msm_dp_display.mst_active) {
 		/* wait until ST_CONNECTED */
 		msm_dp_add_event(dp, EV_IRQ_HPD_INT, 0, 1); /* delay = 1 */
 		mutex_unlock(&dp->event_mutex);
diff --git a/drivers/gpu/drm/msm/dp/dp_mst_drm.c b/drivers/gpu/drm/msm/dp/dp_mst_drm.c
index 2934fe6a93ff8b927b035c01b6007f3f4ec91a3f..2d92084586b466d4953429e8a6fbf766d081cb9f 100644
--- a/drivers/gpu/drm/msm/dp/dp_mst_drm.c
+++ b/drivers/gpu/drm/msm/dp/dp_mst_drm.c
@@ -559,6 +559,40 @@ static struct msm_dp_mst_bridge_state *msm_dp_mst_br_priv_state(struct drm_atomi
 										&bridge->obj));
 }
 
+/* DP MST HPD IRQ callback */
+void msm_dp_mst_display_hpd_irq(struct msm_dp *dp_display)
+{
+	int rc;
+	struct msm_dp_mst *mst = dp_display->msm_dp_mst;
+	u8 ack[8] = {};
+	u8 esi[14];
+	unsigned int esi_res = DP_SINK_COUNT_ESI + 1;
+	bool handled;
+
+	rc = drm_dp_dpcd_read(mst->dp_aux, DP_SINK_COUNT_ESI,
+			      esi, 14);
+	if (rc != 14) {
+		DRM_ERROR("dpcd sink status read failed, rlen=%d\n", rc);
+		return;
+	}
+
+	drm_dbg_dp(dp_display->drm_dev, "mst irq: esi1[0x%x] esi2[0x%x] esi3[%x]\n",
+		   esi[1], esi[2], esi[3]);
+
+	rc = drm_dp_mst_hpd_irq_handle_event(&mst->mst_mgr, esi, ack, &handled);
+
+	/* ack the request */
+	if (handled) {
+		rc = drm_dp_dpcd_writeb(mst->dp_aux, esi_res, ack[1]);
+
+		if (rc != 1)
+			DRM_ERROR("dpcd esi_res failed. rc=%d\n", rc);
+
+		drm_dp_mst_hpd_irq_send_new_request(&mst->mst_mgr);
+	}
+	drm_dbg_dp(dp_display->drm_dev, "mst display hpd_irq handled:%d rc:%d\n", handled, rc);
+}
+
 /* DP MST Connector OPs */
 static int
 msm_dp_mst_connector_detect(struct drm_connector *connector,
@@ -570,7 +604,7 @@ msm_dp_mst_connector_detect(struct drm_connector *connector,
 	struct msm_dp_mst *mst = dp_display->msm_dp_mst;
 	enum drm_connector_status status = connector_status_disconnected;
 
-	if (dp_display->link_ready)
+	if (dp_display->link_ready && dp_display->mst_active)
 		status = drm_dp_mst_detect_port(connector,
 						ctx, &mst->mst_mgr, mst_conn->mst_port);
 
diff --git a/drivers/gpu/drm/msm/dp/dp_mst_drm.h b/drivers/gpu/drm/msm/dp/dp_mst_drm.h
index 9a8535b97193d911592b44fdfcf43ca2f252cea0..5fe5dc7596086467e9a3b3d7d04a665853fbb3d7 100644
--- a/drivers/gpu/drm/msm/dp/dp_mst_drm.h
+++ b/drivers/gpu/drm/msm/dp/dp_mst_drm.h
@@ -103,4 +103,6 @@ int msm_dp_mst_drm_bridge_init(struct msm_dp *dp, struct drm_encoder *encoder);
 int msm_dp_mst_init(struct msm_dp *dp_display, u32 max_streams,
 		    u32 max_dpcd_transaction_bytes, struct drm_dp_aux *drm_aux);
 
+void msm_dp_mst_display_hpd_irq(struct msm_dp *dp_display);
+
 #endif /* _DP_MST_DRM_H_ */

-- 
2.34.1