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Diffstat (limited to 'Documentation/driver-api/soundwire/stream.rst')
| -rw-r--r-- | Documentation/driver-api/soundwire/stream.rst | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/Documentation/driver-api/soundwire/stream.rst b/Documentation/driver-api/soundwire/stream.rst index 29121aa55fb96..26a6064503fdb 100644 --- a/Documentation/driver-api/soundwire/stream.rst +++ b/Documentation/driver-api/soundwire/stream.rst @@ -101,6 +101,34 @@ interface. :: +--------------------+ | | +----------------+ +Example 5: Stereo Stream with L and R channel is rendered by 2 Masters, each +rendering one channel, and is received by two different Slaves, each +receiving one channel. Both Masters and both Slaves are using single port. :: + + +---------------+ Clock Signal +---------------+ + | Master +----------------------------------+ Slave | + | Interface | | Interface | + | 1 | | 1 | + | | Data Signal | | + | L +----------------------------------+ L | + | (Data) | Data Direction | (Data) | + +---------------+ +-----------------------> +---------------+ + + +---------------+ Clock Signal +---------------+ + | Master +----------------------------------+ Slave | + | Interface | | Interface | + | 2 | | 2 | + | | Data Signal | | + | R +----------------------------------+ R | + | (Data) | Data Direction | (Data) | + +---------------+ +-----------------------> +---------------+ + +Note: In multi-link cases like above, to lock, one would acquire a global +lock and then go on locking bus instances. But, in this case the caller +framework(ASoC DPCM) guarantees that stream operations on a card are +always serialized. So, there is no race condition and hence no need for +global lock. + SoundWire Stream Management flow ================================ @@ -174,6 +202,7 @@ per stream. From ASoC DPCM framework, this stream state maybe linked to .startup() operation. .. code-block:: c + int sdw_alloc_stream(char * stream_name); @@ -200,6 +229,7 @@ only be invoked once by respective Master(s) and Slave(s). From ASoC DPCM framework, this stream state is linked to .hw_params() operation. .. code-block:: c + int sdw_stream_add_master(struct sdw_bus * bus, struct sdw_stream_config * stream_config, struct sdw_ports_config * ports_config, @@ -245,6 +275,7 @@ stream. From ASoC DPCM framework, this stream state is linked to .prepare() operation. .. code-block:: c + int sdw_prepare_stream(struct sdw_stream_runtime * stream); @@ -274,6 +305,7 @@ stream. From ASoC DPCM framework, this stream state is linked to .trigger() start operation. .. code-block:: c + int sdw_enable_stream(struct sdw_stream_runtime * stream); SDW_STREAM_DISABLED @@ -301,6 +333,7 @@ per stream. From ASoC DPCM framework, this stream state is linked to .trigger() stop operation. .. code-block:: c + int sdw_disable_stream(struct sdw_stream_runtime * stream); @@ -325,6 +358,7 @@ per stream. From ASoC DPCM framework, this stream state is linked to .trigger() stop operation. .. code-block:: c + int sdw_deprepare_stream(struct sdw_stream_runtime * stream); @@ -349,6 +383,7 @@ all the Master(s) and Slave(s) associated with stream. From ASoC DPCM framework, this stream state is linked to .hw_free() operation. .. code-block:: c + int sdw_stream_remove_master(struct sdw_bus * bus, struct sdw_stream_runtime * stream); int sdw_stream_remove_slave(struct sdw_slave * slave, @@ -361,6 +396,7 @@ stream assigned as part of ALLOCATED state. In .shutdown() the data structure maintaining stream state are freed up. .. code-block:: c + void sdw_release_stream(struct sdw_stream_runtime * stream); Not Supported |