18236370a0
In previous commits we cancelled deferred work, but there is still a window of time where a new interrupt could result in new deferred work executed after the link is disabled, leading to an IO error. While we did not see this IO error on RT711-based platforms, the code pattern is similar to the RT700 case where the IO error was noted, so the fix is added for consistency. This patch uses an 'disable_irq_lock' mutex to prevent new interrupts from happening after the start of the system suspend. The choice of a mutex v. a spinlock is mainly due to the time required to clear interrupts, which requires a command to be transmitted by the SoundWire host IP and acknowledged with an interrupt. The 'interrupt_callback' routine is also not meant to be called from an interrupt context. An additional 'disable_irq' flag prevents race conditions where the status changes before the interrupts are disabled, but the workqueue handling status changes is scheduled after the completion of the system suspend. On resume the interrupts are re-enabled already by the io_init routine so we only clear the flag. BugLink: https://github.com/thesofproject/linux/issues/2943 Fixes: 501ef013390b ('ASoC: rt711: wait for the delayed work to finish when the system suspends') Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> Reviewed-by: Bard Liao <bard.liao@intel.com> Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com> Link: https://lore.kernel.org/r/20210614180815.153711-4-pierre-louis.bossart@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.