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 v5: - Add a debug print to note which state we transition to in snd_compr_stop_error
It might be easiest to put the ASoC changes through Mark's tree as there are some merge conflicts otherwise, as such I have based this series on Mark's tree.
Thanks, Charles
Charles Keepax (4): ALSA: compress: Replace complex if statement with switch ALSA: compress: Add function to indicate the stream has gone bad ASoC: wm_adsp: Use new snd_compr_stop_error to signal stream failure ASoC: compress: Pass error out of soc_compr_pointer
include/sound/compress_driver.h | 5 +++ sound/core/compress_offload.c | 81 ++++++++++++++++++++++++++++++++++++++--- sound/soc/codecs/wm_adsp.c | 11 +++++- sound/soc/soc-compress.c | 5 ++- 4 files changed, 93 insertions(+), 9 deletions(-)