• Kai Vehmanen's avatar
    ASoC: SOF: pm: save io region state in case of errors in resume · 171b53be
    Kai Vehmanen authored
    If there are failures in DSP runtime resume, the device state will not
    reach active and this makes it impossible e.g. to retrieve a possible
    DSP panic dump via "exception" debugfs node. If
    CONFIG_SND_SOC_SOF_DEBUG_ENABLE_DEBUGFS_CACHE=y is set, the data in
    cache is stale. If debugfs cache is not used, the region simply cannot
    be read.
    
    To allow debugging these scenarios, update the debugfs cache contents in
    resume error handler. User-space can then later retrieve DSP panic and
    other state via debugfs (requires SOF debugfs cache to be enabled in
    build).
    
    Reported-by: Curtis Malainey <cujomalainey@chromium.org
    Link: https://github.com/thesofproject/linux/issues/4274
    Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com
    Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com
    Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com
    Reviewed-by: Curtis Malainey <cujomalainey@chromium.org
    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/20230512104638.21376-1-peter.ujfalusi@linux.intel.com
    Signed-off-by: Mark Brown <broonie@kernel.org
    171b53be
pm.c 10 KB