4 files changed, 29 insertions, 21 deletions

diff --git a/drivers/bus/fsl-mc/fsl-mc-bus.c b/drivers/bus/fsl-mc/fsl-mc-bus.c
index 930d8a3ba722..4575d9a4e5ed 100644
--- a/drivers/bus/fsl-mc/fsl-mc-bus.c
+++ b/drivers/bus/fsl-mc/fsl-mc-bus.c
@@ -905,8 +905,10 @@ int fsl_mc_device_add(struct fsl_mc_obj_desc *obj_desc,
 
 error_cleanup_dev:
 	kfree(mc_dev->regions);
-	kfree(mc_bus);
-	kfree(mc_dev);
+	if (mc_bus)
+		kfree(mc_bus);
+	else
+		kfree(mc_dev);
 
 	return error;
 }
@@ -940,6 +942,7 @@ struct fsl_mc_device *fsl_mc_get_endpoint(struct fsl_mc_device *mc_dev,
 	struct fsl_mc_obj_desc endpoint_desc = {{ 0 }};
 	struct dprc_endpoint endpoint1 = {{ 0 }};
 	struct dprc_endpoint endpoint2 = {{ 0 }};
+	struct fsl_mc_bus *mc_bus;
 	int state, err;
 
 	mc_bus_dev = to_fsl_mc_device(mc_dev->dev.parent);
@@ -963,6 +966,8 @@ struct fsl_mc_device *fsl_mc_get_endpoint(struct fsl_mc_device *mc_dev,
 	strcpy(endpoint_desc.type, endpoint2.type);
 	endpoint_desc.id = endpoint2.id;
 	endpoint = fsl_mc_device_lookup(&endpoint_desc, mc_bus_dev);
+	if (endpoint)
+		return endpoint;
 
 	/*
 	 * We know that the device has an endpoint because we verified by
@@ -970,17 +975,13 @@ struct fsl_mc_device *fsl_mc_get_endpoint(struct fsl_mc_device *mc_dev,
 	 * yet discovered by the fsl-mc bus, thus the lookup returned NULL.
 	 * Force a rescan of the devices in this container and retry the lookup.
 	 */
-	if (!endpoint) {
-		struct fsl_mc_bus *mc_bus = to_fsl_mc_bus(mc_bus_dev);
-
-		if (mutex_trylock(&mc_bus->scan_mutex)) {
-			err = dprc_scan_objects(mc_bus_dev, true);
-			mutex_unlock(&mc_bus->scan_mutex);
-		}
-
-		if (err < 0)
-			return ERR_PTR(err);
+	mc_bus = to_fsl_mc_bus(mc_bus_dev);
+	if (mutex_trylock(&mc_bus->scan_mutex)) {
+		err = dprc_scan_objects(mc_bus_dev, true);
+		mutex_unlock(&mc_bus->scan_mutex);
 	}
+	if (err < 0)
+		return ERR_PTR(err);
 
 	endpoint = fsl_mc_device_lookup(&endpoint_desc, mc_bus_dev);
 	/*
diff --git a/drivers/bus/fsl-mc/fsl-mc-uapi.c b/drivers/bus/fsl-mc/fsl-mc-uapi.c
index 9c4c1395fcdb..a376ec661653 100644
--- a/drivers/bus/fsl-mc/fsl-mc-uapi.c
+++ b/drivers/bus/fsl-mc/fsl-mc-uapi.c
@@ -275,13 +275,13 @@ static struct fsl_mc_cmd_desc fsl_mc_accepted_cmds[] = {
 		.size = 8,
 	},
 	[DPSW_GET_TAILDROP] = {
-		.cmdid_value = 0x0A80,
+		.cmdid_value = 0x0A90,
 		.cmdid_mask = 0xFFF0,
 		.token = true,
 		.size = 14,
 	},
 	[DPSW_SET_TAILDROP] = {
-		.cmdid_value = 0x0A90,
+		.cmdid_value = 0x0A80,
 		.cmdid_mask = 0xFFF0,
 		.token = true,
 		.size = 24,
diff --git a/drivers/bus/fsl-mc/mc-io.c b/drivers/bus/fsl-mc/mc-io.c
index 95b10a6cf307..8b7a34f4db94 100644
--- a/drivers/bus/fsl-mc/mc-io.c
+++ b/drivers/bus/fsl-mc/mc-io.c
@@ -214,12 +214,19 @@ int __must_check fsl_mc_portal_allocate(struct fsl_mc_device *mc_dev,
 	if (error < 0)
 		goto error_cleanup_resource;
 
-	dpmcp_dev->consumer_link = device_link_add(&mc_dev->dev,
-						   &dpmcp_dev->dev,
-						   DL_FLAG_AUTOREMOVE_CONSUMER);
-	if (!dpmcp_dev->consumer_link) {
-		error = -EINVAL;
-		goto error_cleanup_mc_io;
+	/* If the DPRC device itself tries to allocate a portal (usually for
+	 * UAPI interaction), don't add a device link between them since the
+	 * DPMCP device is an actual child device of the DPRC and a reverse
+	 * dependency is not allowed.
+	 */
+	if (mc_dev != mc_bus_dev) {
+		dpmcp_dev->consumer_link = device_link_add(&mc_dev->dev,
+							   &dpmcp_dev->dev,
+							   DL_FLAG_AUTOREMOVE_CONSUMER);
+		if (!dpmcp_dev->consumer_link) {
+			error = -EINVAL;
+			goto error_cleanup_mc_io;
+		}
 	}
 
 	*new_mc_io = mc_io;
diff --git a/drivers/bus/fsl-mc/mc-sys.c b/drivers/bus/fsl-mc/mc-sys.c
index f2052cd0a051..b22c59d57c8f 100644
--- a/drivers/bus/fsl-mc/mc-sys.c
+++ b/drivers/bus/fsl-mc/mc-sys.c
@@ -19,7 +19,7 @@
 /*
  * Timeout in milliseconds to wait for the completion of an MC command
  */
-#define MC_CMD_COMPLETION_TIMEOUT_MS	500
+#define MC_CMD_COMPLETION_TIMEOUT_MS	15000
 
 /*
  * usleep_range() min and max values used to throttle down polling