diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index d2c19791b2b6..b90cca361afe 100644
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -1197,16 +1197,8 @@ static int drm_dp_mst_wait_tx_reply(struct drm_dp_mst_branch *mstb,
 
 		/* remove from q */
 		if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED ||
-		    txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND) {
+		    txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND)
 			list_del(&txmsg->next);
-		}
-
-		if (txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND ||
-		    txmsg->state == DRM_DP_SIDEBAND_TX_SENT) {
-			mstb->tx_slots[txmsg->seqno] = NULL;
-		}
-		mgr->is_waiting_for_dwn_reply = false;
-
 	}
 out:
 	if (unlikely(ret == -EIO) && drm_debug_enabled(DRM_UT_DP)) {
@@ -2685,22 +2677,6 @@ static int set_hdr_from_dst_qlock(struct drm_dp_sideband_msg_hdr *hdr,
 	struct drm_dp_mst_branch *mstb = txmsg->dst;
 	u8 req_type;
 
-	/* both msg slots are full */
-	if (txmsg->seqno == -1) {
-		if (mstb->tx_slots[0] && mstb->tx_slots[1]) {
-			DRM_DEBUG_KMS("%s: failed to find slot\n", __func__);
-			return -EAGAIN;
-		}
-		if (mstb->tx_slots[0] == NULL && mstb->tx_slots[1] == NULL) {
-			txmsg->seqno = mstb->last_seqno;
-			mstb->last_seqno ^= 1;
-		} else if (mstb->tx_slots[0] == NULL)
-			txmsg->seqno = 0;
-		else
-			txmsg->seqno = 1;
-		mstb->tx_slots[txmsg->seqno] = txmsg;
-	}
-
 	req_type = txmsg->msg[0] & 0x7f;
 	if (req_type == DP_CONNECTION_STATUS_NOTIFY ||
 		req_type == DP_RESOURCE_STATUS_NOTIFY)
@@ -2712,7 +2688,7 @@ static int set_hdr_from_dst_qlock(struct drm_dp_sideband_msg_hdr *hdr,
 	hdr->lcr = mstb->lct - 1;
 	if (mstb->lct > 1)
 		memcpy(hdr->rad, mstb->rad, mstb->lct / 2);
-	hdr->seqno = txmsg->seqno;
+
 	return 0;
 }
 /*
@@ -2727,15 +2703,15 @@ static int process_single_tx_qlock(struct drm_dp_mst_topology_mgr *mgr,
 	int len, space, idx, tosend;
 	int ret;
 
+	if (txmsg->state == DRM_DP_SIDEBAND_TX_SENT)
+		return 0;
+
 	memset(&hdr, 0, sizeof(struct drm_dp_sideband_msg_hdr));
 
-	if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED) {
-		txmsg->seqno = -1;
+	if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED)
 		txmsg->state = DRM_DP_SIDEBAND_TX_START_SEND;
-	}
 
-	/* make hdr from dst mst - for replies use seqno
-	   otherwise assign one */
+	/* make hdr from dst mst */
 	ret = set_hdr_from_dst_qlock(&hdr, txmsg);
 	if (ret < 0)
 		return ret;
@@ -2788,42 +2764,17 @@ static void process_single_down_tx_qlock(struct drm_dp_mst_topology_mgr *mgr)
 	if (list_empty(&mgr->tx_msg_downq))
 		return;
 
-	txmsg = list_first_entry(&mgr->tx_msg_downq, struct drm_dp_sideband_msg_tx, next);
+	txmsg = list_first_entry(&mgr->tx_msg_downq,
+				 struct drm_dp_sideband_msg_tx, next);
 	ret = process_single_tx_qlock(mgr, txmsg, false);
-	if (ret == 1) {
-		/* txmsg is sent it should be in the slots now */
-		mgr->is_waiting_for_dwn_reply = true;
-		list_del(&txmsg->next);
-	} else if (ret) {
+	if (ret < 0) {
 		DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
-		mgr->is_waiting_for_dwn_reply = false;
 		list_del(&txmsg->next);
-		if (txmsg->seqno != -1)
-			txmsg->dst->tx_slots[txmsg->seqno] = NULL;
 		txmsg->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
 		wake_up_all(&mgr->tx_waitq);
 	}
 }
 
-/* called holding qlock */
-static void process_single_up_tx_qlock(struct drm_dp_mst_topology_mgr *mgr,
-				       struct drm_dp_sideband_msg_tx *txmsg)
-{
-	int ret;
-
-	/* construct a chunk from the first msg in the tx_msg queue */
-	ret = process_single_tx_qlock(mgr, txmsg, true);
-
-	if (ret != 1)
-		DRM_DEBUG_KMS("failed to send msg in q %d\n", ret);
-
-	if (txmsg->seqno != -1) {
-		WARN_ON((unsigned int)txmsg->seqno >
-			ARRAY_SIZE(txmsg->dst->tx_slots));
-		txmsg->dst->tx_slots[txmsg->seqno] = NULL;
-	}
-}
-
 static void drm_dp_queue_down_tx(struct drm_dp_mst_topology_mgr *mgr,
 				 struct drm_dp_sideband_msg_tx *txmsg)
 {
@@ -2836,8 +2787,7 @@ static void drm_dp_queue_down_tx(struct drm_dp_mst_topology_mgr *mgr,
 		drm_dp_mst_dump_sideband_msg_tx(&p, txmsg);
 	}
 
-	if (list_is_singular(&mgr->tx_msg_downq) &&
-	    !mgr->is_waiting_for_dwn_reply)
+	if (list_is_singular(&mgr->tx_msg_downq))
 		process_single_down_tx_qlock(mgr);
 	mutex_unlock(&mgr->qlock);
 }
@@ -3457,7 +3407,7 @@ static int drm_dp_encode_up_ack_reply(struct drm_dp_sideband_msg_tx *msg, u8 req
 
 static int drm_dp_send_up_ack_reply(struct drm_dp_mst_topology_mgr *mgr,
 				    struct drm_dp_mst_branch *mstb,
-				    int req_type, int seqno, bool broadcast)
+				    int req_type, bool broadcast)
 {
 	struct drm_dp_sideband_msg_tx *txmsg;
 
@@ -3466,13 +3416,11 @@ static int drm_dp_send_up_ack_reply(struct drm_dp_mst_topology_mgr *mgr,
 		return -ENOMEM;
 
 	txmsg->dst = mstb;
-	txmsg->seqno = seqno;
 	drm_dp_encode_up_ack_reply(txmsg, req_type);
 
 	mutex_lock(&mgr->qlock);
-
-	process_single_up_tx_qlock(mgr, txmsg);
-
+	/* construct a chunk from the first msg in the tx_msg queue */
+	process_single_tx_qlock(mgr, txmsg, true);
 	mutex_unlock(&mgr->qlock);
 
 	kfree(txmsg);
@@ -3697,8 +3645,9 @@ int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr,
 }
 EXPORT_SYMBOL(drm_dp_mst_topology_mgr_resume);
 
-static bool drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up,
-				  struct drm_dp_mst_branch **mstb, int *seqno)
+static bool
+drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up,
+		      struct drm_dp_mst_branch **mstb)
 {
 	int len;
 	u8 replyblock[32];
@@ -3706,13 +3655,13 @@ static bool drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up,
 	int ret;
 	u8 hdrlen;
 	struct drm_dp_sideband_msg_hdr hdr;
-	struct drm_dp_sideband_msg_rx *msg;
+	struct drm_dp_sideband_msg_rx *msg =
+		up ? &mgr->up_req_recv : &mgr->down_rep_recv;
 	int basereg = up ? DP_SIDEBAND_MSG_UP_REQ_BASE :
 			   DP_SIDEBAND_MSG_DOWN_REP_BASE;
 
 	if (!up)
 		*mstb = NULL;
-	*seqno = -1;
 
 	len = min(mgr->max_dpcd_transaction_bytes, 16);
 	ret = drm_dp_dpcd_read(mgr->aux, basereg, replyblock, len);
@@ -3729,11 +3678,7 @@ static bool drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up,
 		return false;
 	}
 
-	*seqno = hdr.seqno;
-
-	if (up) {
-		msg = &mgr->up_req_recv;
-	} else {
+	if (!up) {
 		/* Caller is responsible for giving back this reference */
 		*mstb = drm_dp_get_mst_branch_device(mgr, hdr.lct, hdr.rad);
 		if (!*mstb) {
@@ -3741,7 +3686,6 @@ static bool drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up,
 				      hdr.lct);
 			return false;
 		}
-		msg = &(*mstb)->down_rep_recv[hdr.seqno];
 	}
 
 	if (!drm_dp_sideband_msg_set_header(msg, &hdr, hdrlen)) {
@@ -3785,13 +3729,10 @@ static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr)
 {
 	struct drm_dp_sideband_msg_tx *txmsg;
 	struct drm_dp_mst_branch *mstb = NULL;
-	struct drm_dp_sideband_msg_rx *msg = NULL;
-	int seqno = -1;
+	struct drm_dp_sideband_msg_rx *msg = &mgr->down_rep_recv;
 
-	if (!drm_dp_get_one_sb_msg(mgr, false, &mstb, &seqno))
-		goto out_clear_reply;
-
-	msg = &mstb->down_rep_recv[seqno];
+	if (!drm_dp_get_one_sb_msg(mgr, false, &mstb))
+		goto out;
 
 	/* Multi-packet message transmission, don't clear the reply */
 	if (!msg->have_eomt)
@@ -3799,11 +3740,12 @@ static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr)
 
 	/* find the message */
 	mutex_lock(&mgr->qlock);
-	txmsg = mstb->tx_slots[seqno];
-	/* remove from slots */
+	txmsg = list_first_entry_or_null(&mgr->tx_msg_downq,
+					 struct drm_dp_sideband_msg_tx, next);
 	mutex_unlock(&mgr->qlock);
 
-	if (!txmsg) {
+	/* Were we actually expecting a response, and from this mstb? */
+	if (!txmsg || txmsg->dst != mstb) {
 		struct drm_dp_sideband_msg_hdr *hdr;
 		hdr = &msg->initial_hdr;
 		DRM_DEBUG_KMS("Got MST reply with no msg %p %d %d %02x %02x\n",
@@ -3828,8 +3770,7 @@ static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr)
 
 	mutex_lock(&mgr->qlock);
 	txmsg->state = DRM_DP_SIDEBAND_TX_RX;
-	mstb->tx_slots[seqno] = NULL;
-	mgr->is_waiting_for_dwn_reply = false;
+	list_del(&txmsg->next);
 	mutex_unlock(&mgr->qlock);
 
 	wake_up_all(&mgr->tx_waitq);
@@ -3837,11 +3778,7 @@ static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr)
 	return 0;
 
 out_clear_reply:
-	mutex_lock(&mgr->qlock);
-	mgr->is_waiting_for_dwn_reply = false;
-	mutex_unlock(&mgr->qlock);
-	if (msg)
-		memset(msg, 0, sizeof(struct drm_dp_sideband_msg_rx));
+	memset(msg, 0, sizeof(struct drm_dp_sideband_msg_rx));
 out:
 	if (mstb)
 		drm_dp_mst_topology_put_mstb(mstb);
@@ -3921,9 +3858,8 @@ static void drm_dp_mst_up_req_work(struct work_struct *work)
 static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr)
 {
 	struct drm_dp_pending_up_req *up_req;
-	int seqno;
 
-	if (!drm_dp_get_one_sb_msg(mgr, true, NULL, &seqno))
+	if (!drm_dp_get_one_sb_msg(mgr, true, NULL))
 		goto out;
 
 	if (!mgr->up_req_recv.have_eomt)
@@ -3947,7 +3883,7 @@ static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr)
 	}
 
 	drm_dp_send_up_ack_reply(mgr, mgr->mst_primary, up_req->msg.req_type,
-				 seqno, false);
+				 false);
 
 	if (up_req->msg.req_type == DP_CONNECTION_STATUS_NOTIFY) {
 		const struct drm_dp_connection_status_notify *conn_stat =
@@ -4692,7 +4628,7 @@ static void drm_dp_tx_work(struct work_struct *work)
 	struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, tx_work);
 
 	mutex_lock(&mgr->qlock);
-	if (!list_empty(&mgr->tx_msg_downq) && !mgr->is_waiting_for_dwn_reply)
+	if (!list_empty(&mgr->tx_msg_downq))
 		process_single_down_tx_qlock(mgr);
 	mutex_unlock(&mgr->qlock);
 }
@@ -4713,26 +4649,25 @@ static inline void
 drm_dp_delayed_destroy_mstb(struct drm_dp_mst_branch *mstb)
 {
 	struct drm_dp_mst_topology_mgr *mgr = mstb->mgr;
-	struct drm_dp_mst_port *port, *tmp;
+	struct drm_dp_mst_port *port, *port_tmp;
+	struct drm_dp_sideband_msg_tx *txmsg, *txmsg_tmp;
 	bool wake_tx = false;
 
 	mutex_lock(&mgr->lock);
-	list_for_each_entry_safe(port, tmp, &mstb->ports, next) {
+	list_for_each_entry_safe(port, port_tmp, &mstb->ports, next) {
 		list_del(&port->next);
 		drm_dp_mst_topology_put_port(port);
 	}
 	mutex_unlock(&mgr->lock);
 
-	/* drop any tx slots msg */
+	/* drop any tx slot msg */
 	mutex_lock(&mstb->mgr->qlock);
-	if (mstb->tx_slots[0]) {
-		mstb->tx_slots[0]->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
-		mstb->tx_slots[0] = NULL;
-		wake_tx = true;
-	}
-	if (mstb->tx_slots[1]) {
-		mstb->tx_slots[1]->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
-		mstb->tx_slots[1] = NULL;
+	list_for_each_entry_safe(txmsg, txmsg_tmp, &mgr->tx_msg_downq, next) {
+		if (txmsg->dst != mstb)
+			continue;
+
+		txmsg->state = DRM_DP_SIDEBAND_TX_TIMEOUT;
+		list_del(&txmsg->next);
 		wake_tx = true;
 	}
 	mutex_unlock(&mstb->mgr->qlock);
diff --git a/include/drm/drm_dp_mst_helper.h b/include/drm/drm_dp_mst_helper.h
index 96bcf33c03d3..9e1ffcd7cb68 100644
--- a/include/drm/drm_dp_mst_helper.h
+++ b/include/drm/drm_dp_mst_helper.h
@@ -194,11 +194,8 @@ struct drm_dp_sideband_msg_rx {
  * @rad: Relative Address to talk to this branch device.
  * @lct: Link count total to talk to this branch device.
  * @num_ports: number of ports on the branch.
- * @msg_slots: one bit per transmitted msg slot.
  * @port_parent: pointer to the port parent, NULL if toplevel.
  * @mgr: topology manager for this branch device.
- * @tx_slots: transmission slots for this device.
- * @last_seqno: last sequence number used to talk to this.
  * @link_address_sent: if a link address message has been sent to this device yet.
  * @guid: guid for DP 1.2 branch device. port under this branch can be
  * identified by port #.
@@ -239,7 +236,6 @@ struct drm_dp_mst_branch {
 	u8 lct;
 	int num_ports;
 
-	int msg_slots;
 	/**
 	 * @ports: the list of ports on this branch device. This should be
 	 * considered protected for reading by &drm_dp_mst_topology_mgr.lock.
@@ -252,20 +248,11 @@ struct drm_dp_mst_branch {
 	 */
 	struct list_head ports;
 
-	/* list of tx ops queue for this port */
 	struct drm_dp_mst_port *port_parent;
 	struct drm_dp_mst_topology_mgr *mgr;
 
-	/* slots are protected by mstb->mgr->qlock */
-	struct drm_dp_sideband_msg_tx *tx_slots[2];
-	int last_seqno;
 	bool link_address_sent;
 
-	/**
-	 * @down_rep_recv: Message receiver state for down replies.
-	 */
-	struct drm_dp_sideband_msg_rx down_rep_recv[2];
-
 	/* global unique identifier to identify branch devices */
 	u8 guid[16];
 };
@@ -567,6 +554,12 @@ struct drm_dp_mst_topology_mgr {
 	 */
 	struct drm_dp_sideband_msg_rx up_req_recv;
 
+	/**
+	 * @down_rep_recv: Message receiver state for replies to down
+	 * requests.
+	 */
+	struct drm_dp_sideband_msg_rx down_rep_recv;
+
 	/**
 	 * @lock: protects @mst_state, @mst_primary, @dpcd, and
 	 * @payload_id_table_cleared.
@@ -592,11 +585,6 @@ struct drm_dp_mst_topology_mgr {
 	 */
 	bool payload_id_table_cleared : 1;
 
-	/**
-	 * @is_waiting_for_dwn_reply: whether we're waiting for a down reply.
-	 */
-	bool is_waiting_for_dwn_reply : 1;
-
 	/**
 	 * @mst_primary: Pointer to the primary/first branch device.
 	 */
@@ -621,13 +609,12 @@ struct drm_dp_mst_topology_mgr {
 	const struct drm_private_state_funcs *funcs;
 
 	/**
-	 * @qlock: protects @tx_msg_downq, the &drm_dp_mst_branch.txslost and
-	 * &drm_dp_sideband_msg_tx.state once they are queued
+	 * @qlock: protects @tx_msg_downq and &drm_dp_sideband_msg_tx.state
 	 */
 	struct mutex qlock;
 
 	/**
-	 * @tx_msg_downq: List of pending down replies.
+	 * @tx_msg_downq: List of pending down requests
 	 */
 	struct list_head tx_msg_downq;