[PATCH 6/6] soundwire: stream: don't program ports for a stream that has not been prepared

From: Pierre-Louis Bossart
Date: Wed Jan 08 2020 - 12:55:13 EST


From: Rander Wang <rander.wang@xxxxxxxxx>

In the Intel QA multi-pipelines test case, there are two pipelines for
playback and capture on the same bus. The test fails with an error
when setting port params:

[ 599.224812] rt711 sdw:0:25d:711:0: invalid dpn_prop direction 1 port_num 0
[ 599.224815] sdw_program_slave_port_params failed -22
[ 599.224819] intel-sdw sdw-master-0: Program transport params failed: -22
[ 599.224822] intel-sdw sdw-master-0: Program params failed: -22
[ 599.224828] sdw_enable_stream: SDW0 Pin2-Playback: done

This problem is root-caused to the programming of the capture stream
ports while it is not yet prepared, the calling sequence is:

(1) hw_params for playback. The playback stream provide the port
information to Bus.
(2) stream_prepare for playback, Transport and port parameters
are computed for playback.
(3) hw_params for capture. The capture stream provide the port
information to Bus, but it has not been prepared so is not
accounted for in the bandwidth allocation.
(4) stream_enable for playback. Program transport and port parameters
for all masters and slaves. Since the transport and port parameters
are not computed for capture stream, sdw_program_slave_port_params
will generate a error when setting port params for capture.

in step (4), we should only program the ports for the stream that have
been prepared. A stream that is only in CONFIGURED state should be
ignored, its ports will be programmed when it becomes PREPARED.

Tested on Comet Lake.

GitHub issue: https://github.com/thesofproject/linux/issues/1637
Signed-off-by: Rander Wang <rander.wang@xxxxxxxxx>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@xxxxxxxxxxxxxxx>
---
drivers/soundwire/stream.c | 21 ++++++++++++++++-----
1 file changed, 16 insertions(+), 5 deletions(-)

diff --git a/drivers/soundwire/stream.c b/drivers/soundwire/stream.c
index da10f38298c0..198372977187 100644
--- a/drivers/soundwire/stream.c
+++ b/drivers/soundwire/stream.c
@@ -604,12 +604,23 @@ static int sdw_notify_config(struct sdw_master_runtime *m_rt)
*
* @bus: SDW bus instance
*/
-static int sdw_program_params(struct sdw_bus *bus)
+static int sdw_program_params(struct sdw_bus *bus, bool prepare)
{
struct sdw_master_runtime *m_rt;
int ret = 0;

list_for_each_entry(m_rt, &bus->m_rt_list, bus_node) {
+
+ /*
+ * this loop walks through all master runtimes for a
+ * bus, but the ports can only be configured while
+ * explicitly preparing a stream or handling an
+ * already-prepared stream otherwise.
+ */
+ if (!prepare &&
+ m_rt->stream->state == SDW_STREAM_CONFIGURED)
+ continue;
+
ret = sdw_program_port_params(m_rt);
if (ret < 0) {
dev_err(bus->dev,
@@ -1502,7 +1513,7 @@ static int _sdw_prepare_stream(struct sdw_stream_runtime *stream,

program_params:
/* Program params */
- ret = sdw_program_params(bus);
+ ret = sdw_program_params(bus, true);
if (ret < 0) {
dev_err(bus->dev, "Program params failed: %d\n", ret);
goto restore_params;
@@ -1602,7 +1613,7 @@ static int _sdw_enable_stream(struct sdw_stream_runtime *stream)
bus = m_rt->bus;

/* Program params */
- ret = sdw_program_params(bus);
+ ret = sdw_program_params(bus, false);
if (ret < 0) {
dev_err(bus->dev, "Program params failed: %d\n", ret);
return ret;
@@ -1687,7 +1698,7 @@ static int _sdw_disable_stream(struct sdw_stream_runtime *stream)
struct sdw_bus *bus = m_rt->bus;

/* Program params */
- ret = sdw_program_params(bus);
+ ret = sdw_program_params(bus, false);
if (ret < 0) {
dev_err(bus->dev, "Program params failed: %d\n", ret);
return ret;
@@ -1769,7 +1780,7 @@ static int _sdw_deprepare_stream(struct sdw_stream_runtime *stream)
m_rt->ch_count * m_rt->stream->params.bps;

/* Program params */
- ret = sdw_program_params(bus);
+ ret = sdw_program_params(bus, false);
if (ret < 0) {
dev_err(bus->dev, "Program params failed: %d\n", ret);
return ret;
--
2.20.1