32c4b69872
Use the started_count and paused_count to implement reference counting when making decisions to start/stop/pause pipelines during the FE DAI trigger. This is necessary to trigger the shared pipelines in the FE DAI trigger properly. With IPC4, the FE trigger will issue multiple pipeline state changes, and the triggers are propagated downstream to connected pipelines by the SOF driver - not the firmware. This creates a window for race conditions where an FE trigger preempts another one, which results in inconsistent pipeline states and refcounts. This patch introduces a mutex lock for the pcm trigger that guarantees that IPC4 state and resources are accessed in a serialized manner. Signed-off-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com> Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Reviewed-by: Rander Wang <rander.wang@intel.com> Reviewed-by: Bard Liao <yung-chuan.liao@linux.intel.com> Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com> Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com> Link: https://lore.kernel.org/r/20230127120031.10709-15-peter.ujfalusi@linux.intel.com Signed-off-by: Mark Brown <broonie@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.