kernel/linux.git/Documentation/driver-api/soundwire, branch v6.19.11

soundwire: update Intel BPT message length limitation

2025-06-09T16:12:18+00:00

The limitation of "must be multiples of 32 bytes" does not fit the requirement of current Intel platforms. Update it to meet the requirement. Signed-off-by: Bard Liao Reviewed-by: Ranjani Sridharan Reviewed-by: Péter Ujfalusi Link: https://lore.kernel.org/r/20250429122337.142551-1-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul

soundwire: stream: extend sdw_alloc_stream() to take 'type' parameter

2025-03-10T07:01:18+00:00

In the existing definition of sdw_stream_runtime, the 'type' member is never set and defaults to PCM. To prepare for the BPT/BRA support, we need to special-case streams and make use of the 'type'. No functional change for now, the implicit PCM type is now explicit. Signed-off-by: Pierre-Louis Bossart Signed-off-by: Bard Liao Reviewed-by: Péter Ujfalusi Reviewed-by: Liam Girdwood Reviewed-by: Ranjani Sridharan Tested-by: shumingf@realtek.com Link: https://lore.kernel.org/r/20250227140615.8147-5-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul

Documentation: driver: add SoundWire BRA description

2025-03-10T07:01:18+00:00

The Bulk Register Access protocol was left as a TODO topic since 2018. It's time to document this protocol and the design of its Linux support. Signed-off-by: Pierre-Louis Bossart Signed-off-by: Bard Liao Reviewed-by: Péter Ujfalusi Reviewed-by: Liam Girdwood Reviewed-by: Ranjani Sridharan Reviewed-by: Bagas Sanjaya Tested-by: shumingf@realtek.com Link: https://lore.kernel.org/r/20250227140615.8147-2-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul

soundwire: stream: add missing const to Documentation

2024-01-22T08:27:09+00:00

Commit 21f4c443731f ("soundwire: stream: constify sdw_port_config when adding devices") added const to sdw_port_config argument, but forgot documentation. Fixes: 21f4c443731f ("soundwire: stream: constify sdw_port_config when adding devices") Signed-off-by: Krzysztof Kozlowski Link: https://lore.kernel.org/r/20240117160639.1327266-1-krzysztof.kozlowski@linaro.org Signed-off-by: Vinod Koul

docs: soundwire: fix some identation at stream.rst

2020-09-10T16:49:29+00:00

Currently, sphinx emits one warning on this file: Documentation/driver-api/soundwire/stream.rst:522: WARNING: Block quote ends without a blank line; unexpected unindent. That's due to some extra spaces before the title of a chapter. Yet, the list afterwards is missing identation. So, address both issues. Signed-off-by: Mauro Carvalho Chehab Link: https://lore.kernel.org/r/eddde9f8d121e27d7968b3d747064e16de8bec4f.1599660067.git.mchehab+huawei@kernel.org Signed-off-by: Jonathan Corbet

soundwire: stream: add helper to startup/shutdown streams

2020-07-15T04:40:05+00:00

To handle streams at the dailink level, expose two helpers that will be called from machine drivers. Reviewed-by: Ranjani Sridharan Reviewed-by: Guennadi Liakhovetski Reviewed-by: Kai Vehmanen Signed-off-by: Pierre-Louis Bossart Signed-off-by: Bard Liao Link: https://lore.kernel.org/r/20200630184356.24939-3-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul

soundwire: bus: rename sdw_bus_master_add/delete, add arguments

2020-05-19T07:14:34+00:00

In preparation for future extensions, rename functions to use sdw_bus_master prefix and add a parent and fwnode argument to sdw_bus_master_add to help with device registration in follow-up patches. No functionality change, just renames and additional arguments. The Intel code is currently unused, the two additional arguments are only needed for compilation. Signed-off-by: Pierre-Louis Bossart Signed-off-by: Bard Liao Acked-by: Jaroslav Kysela Link: https://lore.kernel.org/r/20200518174322.31561-2-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul

Documentation: SoundWire: clarify TDM mode support

2020-05-05T03:21:44+00:00

The current description of stream topologies does not explicitly mention 'mirror' topologies used for audio amplifiers, where all amplifiers see the same data and generate a different output based on configuration or dynamic information. Add examples and notes to explain how channels can be transmitted and mapped. Signed-off-by: Pierre-Louis Bossart Signed-off-by: Bard Liao Link: https://lore.kernel.org/r/20200419185117.4233-1-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul

soundwire: stream: update state machine and add state checks

2020-02-13T10:27:37+00:00

The state machine and notes don't accurately explain or allow transitions from STREAM_DEPREPARED and STREAM_DISABLED. Add more explanations and allow for more transitions as a result of a trigger_stop(), trigger_suspend() and prepare(), depending on the ALSA/ASoC layer behavior defined by the INFO_RESUME and INFO_PAUSE flags. Also add basic checks to help debug inconsistent states and illegal state machine transitions. Signed-off-by: Pierre-Louis Bossart Link: https://lore.kernel.org/r/20200114235227.14502-2-pierre-louis.bossart@linux.intel.com Signed-off-by: Vinod Koul

docs: index.rst: don't use genindex for pdf output

2019-07-31T19:31:16+00:00

The genindex logic is meant to be used only for html output, as pdf build has its own way to generate indexes. Signed-off-by: Mauro Carvalho Chehab Acked-by: Vinod Koul # dmaengine and soundwire Signed-off-by: Jonathan Corbet