soundwire: stream: use consistent pattern for freeing buffers

The code should free the message buffer used for data, the message
structure used for control and assign the latter to NULL. The last
part is missing for multi-link cases, and the order is inconsistent
for single-link cases.

Link: thesofproject#4056
Signed-off-by: Pierre-Louis Bossart <[email protected]>
Reviewed-by: Ranjani Sridharan <[email protected]>
Signed-off-by: Bard Liao <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Vinod Koul <[email protected]>

Author: plbossart

drivers/soundwire/stream.c

@@ -723,8 +723,8 @@ static int sdw_bank_switch(struct sdw_bus *bus, int m_rt_count)
 	}
 
 	if (!multi_link) {
-		kfree(wr_msg);
 		kfree(wbuf);
+		kfree(wr_msg);
 		bus->defer_msg.msg = NULL;
 		bus->params.curr_bank = !bus->params.curr_bank;
 		bus->params.next_bank = !bus->params.next_bank;
@@ -769,6 +769,7 @@ static int sdw_ml_sync_bank_switch(struct sdw_bus *bus)
 	if (bus->defer_msg.msg) {
 		kfree(bus->defer_msg.msg->buf);
 		kfree(bus->defer_msg.msg);
+		bus->defer_msg.msg = NULL;
 	}
 
 	return 0;
@@ -867,6 +868,7 @@ static int do_bank_switch(struct sdw_stream_runtime *stream)
 		if (bus->defer_msg.msg) {
 			kfree(bus->defer_msg.msg->buf);
 			kfree(bus->defer_msg.msg);
+			bus->defer_msg.msg = NULL;
 		}
 	}