[PATCH 18/19] soundwire: stream: sdw_stream_add_ functions can be called multiple times

From: Bard Liao
Date: Tue Jan 25 2022 - 20:18:46 EST


From: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>

The sdw_stream_add_slave/master() functions are called from the
.hw_params stage. We need to make sure the functions can be called
multiple times.

In this version, we assume that only 'audio' parameters provide in the
hw_params() can change. If the number of ports could change
dynamically depending on the stream configuration (number of channels,
etc), we would need to free-up all the stream resources and reallocate
them.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
Reviewed-by: Rander Wang <rander.wang@xxxxxxxxx>
Signed-off-by: Bard Liao <yung-chuan.liao@xxxxxxxxxxxxxxx>
---
drivers/soundwire/stream.c | 24 ++++++++++++++++++++++++
1 file changed, 24 insertions(+)

diff --git a/drivers/soundwire/stream.c b/drivers/soundwire/stream.c
index a52a9ab0eea1..ccf3c99dd579 100644
--- a/drivers/soundwire/stream.c
+++ b/drivers/soundwire/stream.c
@@ -898,6 +898,11 @@ static void sdw_port_free(struct sdw_port_runtime *p_rt)
kfree(p_rt);
}

+static bool sdw_slave_port_allocated(struct sdw_slave_runtime *s_rt)
+{
+ return !list_empty(&s_rt->port_list);
+}
+
static void sdw_slave_port_free(struct sdw_slave *slave,
struct sdw_stream_runtime *stream)
{
@@ -972,6 +977,11 @@ static int sdw_slave_port_config(struct sdw_slave *slave,
return 0;
}

+static bool sdw_master_port_allocated(struct sdw_master_runtime *m_rt)
+{
+ return !list_empty(&m_rt->port_list);
+}
+
static void sdw_master_port_free(struct sdw_master_runtime *m_rt)
{
struct sdw_port_runtime *p_rt, *_p_rt;
@@ -1856,12 +1866,17 @@ int sdw_stream_add_master(struct sdw_bus *bus,
}
skip_alloc_master_rt:

+ if (sdw_master_port_allocated(m_rt))
+ goto skip_alloc_master_port;
+
ret = sdw_master_port_alloc(m_rt, num_ports);
if (ret)
goto alloc_error;

stream->m_rt_count++;

+skip_alloc_master_port:
+
ret = sdw_master_rt_config(m_rt, stream_config);
if (ret < 0)
goto unlock;
@@ -1970,6 +1985,10 @@ int sdw_stream_add_slave(struct sdw_slave *slave,
}

skip_alloc_master_rt:
+ s_rt = sdw_slave_rt_find(slave, stream);
+ if (s_rt)
+ goto skip_alloc_slave_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);
@@ -1978,10 +1997,15 @@ int sdw_stream_add_slave(struct sdw_slave *slave,
goto alloc_error;
}

+skip_alloc_slave_rt:
+ if (sdw_slave_port_allocated(s_rt))
+ goto skip_port_alloc;
+
ret = sdw_slave_port_alloc(slave, s_rt, num_ports);
if (ret)
goto alloc_error;

+skip_port_alloc:
ret = sdw_master_rt_config(m_rt, stream_config);
if (ret)
goto unlock;
--
2.17.1