If the DSP suffers an unrecoverable error, the driver likely knows about this, however the framework may not get informed because errors returned from pointer requests are ignored within the framework.
Things work out fine if user-space is doing a read as reads return error status back to user-space so the user can find out that things have gone bad. However, if user-space is doing an avail request there is no path for the error to come back up to user-space. The pointer request returns zero available data, so a read never happens and we basically just end up sitting waiting for data on a stream that we know full well has died.
This patch set attempts to address this and ensure that errors are fully propagated to user-space and we don't ever end up wait for data that will never come.
Changes since v1: - Based on a recommendation from Vinod, rather than handling errors from pointer requests, add a new call that allows us to inform the compress core that the stream has gone bad. Then return errors from the avail and poll callbacks if the stream is bad.
Thanks, Charles
Charles Keepax (6): ASoC: compress: Pass error out of soc_compr_pointer ALSA: compress: Add function to indicate the stream has gone bad ALSA: compress: Replace complex if statement with switch ASoC: wm_adsp: Factor out fetching of stream errors from the DSP ASoC: wm_adsp: Improve DSP error handling ASoC: wm_adsp: Use new snd_compr_stop_xrun to signal stream failure
include/sound/compress_driver.h | 3 ++ sound/core/compress_offload.c | 67 ++++++++++++++++++++++++++++++++++++++--- sound/soc/codecs/wm_adsp.c | 43 +++++++++++++++++++------- sound/soc/soc-compress.c | 5 +-- 4 files changed, 101 insertions(+), 17 deletions(-)