soundwire: stream: separate alloc and config within sdw_stream_add_xxx()

Separate alloc and config parts so that follow-up patches can allow
for multiple calls to sdw_stream_add_slave/master. This is a feature
from the ALSA/ASoC frameworks which is not supported today.

This is an invasive patch which modifies the error handling flow, with
cleanups only done when an allocation fails. Configuration failures
only return an error code.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Signed-off-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Link: https://lore.kernel.org/r/20220126011715.28204-17-yung-chuan.liao@linux.intel.comSigned-off-by: Vinod Koul <vkoul@kernel.org>

drivers/soundwire/stream.c

@@ -1811,6 +1811,7 @@ int sdw_stream_add_master(struct sdw_bus *bus,
 			  struct sdw_stream_runtime *stream)
 {
 	struct sdw_master_runtime *m_rt;
+	bool alloc_master_rt = true;
 	int ret;
 
 	mutex_lock(&bus->bus_lock);
@@ -1832,8 +1833,10 @@ int sdw_stream_add_master(struct sdw_bus *bus,
 	 * it first), if so skip allocation and go to configuration
 	 */
 	m_rt = sdw_master_rt_find(bus, stream);
-	if (m_rt)
+	if (m_rt) {
+		alloc_master_rt = false;
 		goto skip_alloc_master_rt;
+	}
 
 	m_rt = sdw_master_rt_alloc(bus, stream);
 	if (!m_rt) {
@@ -1841,30 +1844,32 @@ int sdw_stream_add_master(struct sdw_bus *bus,
 		ret = -ENOMEM;
 		goto unlock;
 	}
+skip_alloc_master_rt:
+
+	ret = sdw_master_port_alloc(m_rt, num_ports);
+	if (ret)
+		goto alloc_error;
+
+	stream->m_rt_count++;
 
 	ret = sdw_master_rt_config(m_rt, stream_config);
 	if (ret < 0)
 		goto unlock;
 
-skip_alloc_master_rt:
 	ret = sdw_config_stream(bus->dev, stream, stream_config, false);
 	if (ret)
-		goto stream_error;
-
-	ret = sdw_master_port_alloc(m_rt, num_ports);
-	if (ret)
-		goto stream_error;
+		goto unlock;
 
 	ret = sdw_master_port_config(m_rt, port_config);
-	if (ret)
-		goto stream_error;
-
-	stream->m_rt_count++;
 
 	goto unlock;
 
-stream_error:
-	sdw_master_rt_free(m_rt, stream);
+alloc_error:
+	/*
+	 * we only cleanup what was allocated in this routine
+	 */
+	if (alloc_master_rt)
+		sdw_master_rt_free(m_rt, stream);
 unlock:
 	mutex_unlock(&bus->bus_lock);
 	return ret;
@@ -1926,6 +1931,9 @@ int sdw_stream_add_slave(struct sdw_slave *slave,
 {
 	struct sdw_slave_runtime *s_rt;
 	struct sdw_master_runtime *m_rt;
+	bool alloc_master_rt = true;
+	bool alloc_slave_rt = true;
+
 	int ret;
 
 	mutex_lock(&slave->bus->bus_lock);
@@ -1935,8 +1943,10 @@ int sdw_stream_add_slave(struct sdw_slave *slave,
 	 * and go to configuration
 	 */
 	m_rt = sdw_master_rt_find(slave->bus, stream);
-	if (m_rt)
+	if (m_rt) {
+		alloc_master_rt = false;
 		goto skip_alloc_master_rt;
+	}
 
 	/*
 	 * If this API is invoked by Slave first then m_rt is not valid.
@@ -1946,35 +1956,37 @@ int sdw_stream_add_slave(struct sdw_slave *slave,
 	if (!m_rt) {
 		dev_err(&slave->dev, "Master runtime alloc failed for stream:%s\n", stream->name);
 		ret = -ENOMEM;
-		goto error;
+		goto unlock;
 	}
-	ret =  sdw_master_rt_config(m_rt, stream_config);
-	if (ret < 0)
-		goto stream_error;
 
 skip_alloc_master_rt:
 	s_rt = sdw_slave_rt_alloc(slave, m_rt);
 	if (!s_rt) {
 		dev_err(&slave->dev, "Slave runtime alloc failed for stream:%s\n", stream->name);
+		alloc_slave_rt = false;
 		ret = -ENOMEM;
-		goto stream_error;
+		goto alloc_error;
 	}
 
-	ret = sdw_slave_rt_config(s_rt, stream_config);
+	ret = sdw_slave_port_alloc(slave, s_rt, num_ports);
 	if (ret)
-		goto stream_error;
+		goto alloc_error;
 
-	ret = sdw_config_stream(&slave->dev, stream, stream_config, true);
+	ret =  sdw_master_rt_config(m_rt, stream_config);
 	if (ret)
-		goto stream_error;
+		goto unlock;
 
-	ret = sdw_slave_port_alloc(slave, s_rt, num_ports);
+	ret = sdw_slave_rt_config(s_rt, stream_config);
 	if (ret)
-		goto stream_error;
+		goto unlock;
+
+	ret = sdw_config_stream(&slave->dev, stream, stream_config, true);
+	if (ret)
+		goto unlock;
 
 	ret = sdw_slave_port_config(slave, s_rt, port_config);
 	if (ret)
-		goto stream_error;
+		goto unlock;
 
 	/*
 	 * Change stream state to CONFIGURED on first Slave add.
@@ -1983,15 +1995,19 @@ int sdw_stream_add_slave(struct sdw_slave *slave,
 	 * change stream state to CONFIGURED.
 	 */
 	stream->state = SDW_STREAM_CONFIGURED;
-	goto error;
+	goto unlock;
 
-stream_error:
+alloc_error:
 	/*
-	 * we hit error so cleanup the stream, release all Slave(s) and
-	 * Master runtime
+	 * we only cleanup what was allocated in this routine. The 'else if'
+	 * is intentional, the 'master_rt_free' will call sdw_slave_rt_free()
+	 * internally.
 	 */
-	sdw_master_rt_free(m_rt, stream);
-error:
+	if (alloc_master_rt)
+		sdw_master_rt_free(m_rt, stream);
+	else if (alloc_slave_rt)
+		sdw_slave_rt_free(slave, stream);
+unlock:
 	mutex_unlock(&slave->bus->bus_lock);
 	return ret;
 }