drm/dp/mst: deallocate payload on port destruction

[mirror_ubuntu-focal-kernel.git] / drivers / gpu / drm / drm_dp_mst_topology.c

diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c
index 7e5d98c7b908a2054c959476a1a67655974a425a..8ae13de272c43a7f79822098318a5c5317b54483 100644 (file)
--- a/drivers/gpu/drm/drm_dp_mst_topology.c
+++ b/drivers/gpu/drm/drm_dp_mst_topology.c
@@ -803,12 +803,33 @@ static struct drm_dp_mst_branch *drm_dp_add_mst_branch_device(u8 lct, u8 *rad)
        return mstb;
 }
 
+static void drm_dp_free_mst_port(struct kref *kref);
+
+static void drm_dp_free_mst_branch_device(struct kref *kref)
+{
+       struct drm_dp_mst_branch *mstb = container_of(kref, struct drm_dp_mst_branch, kref);
+       if (mstb->port_parent) {
+               if (list_empty(&mstb->port_parent->next))
+                       kref_put(&mstb->port_parent->kref, drm_dp_free_mst_port);
+       }
+       kfree(mstb);
+}
+
 static void drm_dp_destroy_mst_branch_device(struct kref *kref)
 {
        struct drm_dp_mst_branch *mstb = container_of(kref, struct drm_dp_mst_branch, kref);
        struct drm_dp_mst_port *port, *tmp;
        bool wake_tx = false;
 
+       /*
+        * init kref again to be used by ports to remove mst branch when it is
+        * not needed anymore
+        */
+       kref_init(kref);
+
+       if (mstb->port_parent && list_empty(&mstb->port_parent->next))
+               kref_get(&mstb->port_parent->kref);
+
        /*
         * destroy all ports - don't need lock
         * as there are no more references to the mst branch
@@ -835,7 +856,8 @@ static void drm_dp_destroy_mst_branch_device(struct kref *kref)
 
        if (wake_tx)
                wake_up(&mstb->mgr->tx_waitq);
-       kfree(mstb);
+
+       kref_put(kref, drm_dp_free_mst_branch_device);
 }
 
 static void drm_dp_put_mst_branch_device(struct drm_dp_mst_branch *mstb)
@@ -883,6 +905,7 @@ static void drm_dp_destroy_port(struct kref *kref)
                         * from an EDID retrieval */
 
                        mutex_lock(&mgr->destroy_connector_lock);
+                       kref_get(&port->parent->kref);
                        list_add(&port->next, &mgr->destroy_connector_list);
                        mutex_unlock(&mgr->destroy_connector_lock);
                        schedule_work(&mgr->destroy_connector_work);
@@ -1617,6 +1640,37 @@ static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr,
        return 0;
 }
 
+static struct drm_dp_mst_port *drm_dp_get_last_connected_port_to_mstb(struct drm_dp_mst_branch *mstb)
+{
+       if (!mstb->port_parent)
+               return NULL;
+
+       if (mstb->port_parent->mstb != mstb)
+               return mstb->port_parent;
+
+       return drm_dp_get_last_connected_port_to_mstb(mstb->port_parent->parent);
+}
+
+static struct drm_dp_mst_branch *drm_dp_get_last_connected_port_and_mstb(struct drm_dp_mst_topology_mgr *mgr,
+                                                                        struct drm_dp_mst_branch *mstb,
+                                                                        int *port_num)
+{
+       struct drm_dp_mst_branch *rmstb = NULL;
+       struct drm_dp_mst_port *found_port;
+       mutex_lock(&mgr->lock);
+       if (mgr->mst_primary) {
+               found_port = drm_dp_get_last_connected_port_to_mstb(mstb);
+
+               if (found_port) {
+                       rmstb = found_port->parent;
+                       kref_get(&rmstb->kref);
+                       *port_num = found_port->port_num;
+               }
+       }
+       mutex_unlock(&mgr->lock);
+       return rmstb;
+}
+
 static int drm_dp_payload_send_msg(struct drm_dp_mst_topology_mgr *mgr,
                                   struct drm_dp_mst_port *port,
                                   int id,
@@ -1624,13 +1678,18 @@ static int drm_dp_payload_send_msg(struct drm_dp_mst_topology_mgr *mgr,
 {
        struct drm_dp_sideband_msg_tx *txmsg;
        struct drm_dp_mst_branch *mstb;
-       int len, ret;
+       int len, ret, port_num;
        u8 sinks[DRM_DP_MAX_SDP_STREAMS];
        int i;
 
+       port_num = port->port_num;
        mstb = drm_dp_get_validated_mstb_ref(mgr, port->parent);
-       if (!mstb)
-               return -EINVAL;
+       if (!mstb) {
+               mstb = drm_dp_get_last_connected_port_and_mstb(mgr, port->parent, &port_num);
+
+               if (!mstb)
+                       return -EINVAL;
+       }
 
        txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL);
        if (!txmsg) {
@@ -1642,7 +1701,7 @@ static int drm_dp_payload_send_msg(struct drm_dp_mst_topology_mgr *mgr,
                sinks[i] = i;
 
        txmsg->dst = mstb;
-       len = build_allocate_payload(txmsg, port->port_num,
+       len = build_allocate_payload(txmsg, port_num,
                                     id,
                                     pbn, port->num_sdp_streams, sinks);
 
@@ -2788,6 +2847,13 @@ static void drm_dp_tx_work(struct work_struct *work)
        mutex_unlock(&mgr->qlock);
 }
 
+static void drm_dp_free_mst_port(struct kref *kref)
+{
+       struct drm_dp_mst_port *port = container_of(kref, struct drm_dp_mst_port, kref);
+       kref_put(&port->parent->kref, drm_dp_free_mst_branch_device);
+       kfree(port);
+}
+
 static void drm_dp_destroy_connector_work(struct work_struct *work)
 {
        struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, destroy_connector_work);
@@ -2808,13 +2874,22 @@ static void drm_dp_destroy_connector_work(struct work_struct *work)
                list_del(&port->next);
                mutex_unlock(&mgr->destroy_connector_lock);
 
+               kref_init(&port->kref);
+               INIT_LIST_HEAD(&port->next);
+
                mgr->cbs->destroy_connector(mgr, port->connector);
 
                drm_dp_port_teardown_pdt(port, port->pdt);
 
-               if (!port->input && port->vcpi.vcpi > 0)
-                       drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
-               kfree(port);
+               if (!port->input && port->vcpi.vcpi > 0) {
+                       if (mgr->mst_state) {
+                               drm_dp_mst_reset_vcpi_slots(mgr, port);
+                               drm_dp_update_payload_part1(mgr);
+                               drm_dp_mst_put_payload_id(mgr, port->vcpi.vcpi);
+                       }
+               }
+
+               kref_put(&port->kref, drm_dp_free_mst_port);
                send_hotplug = true;
        }
        if (send_hotplug)