diff options
| author | Srinivas Kandagatla <srinivas.kandagatla@linaro.org> | 2022-02-25 13:38:24 +0000 |
|---|---|---|
| committer | Srinivas Kandagatla <srinivas.kandagatla@linaro.org> | 2023-06-02 15:36:55 +0100 |
| commit | 022cff9e3a77827e0cd537a3e35cf7a569d13c27 (patch) | |
| tree | 344133d96718fed13bd7cc5d2662980a18f99b80 | |
| parent | b55c9c69947cf351f6053fd4e3d88ff547e489ef (diff) | |
ALSA: compress: allow setting codec params after next trackaudioreach/compress-offload
For gapless playback it is possible that each track can have different
codec profile with same decoder, for example we have WMA album,
we may have different tracks as WMA v9, WMA v10 and so on
Or if DSP's like QDSP have abililty to switch decoders on single stream
for each track, then this call could be used to set new codec parameters.
Existing code does not allow to change this profile while doing gapless
playback.
Reuse existing SNDRV_COMPRESS_SET_PARAMS to set this new track params along
some additional checks to enforce proper state machine.
With this new changes now the user can call SNDRV_COMPRESS_SET_PARAMS
anytime after setting next track and additional check in write should
also ensure that params are set before writing new data.
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
| -rw-r--r-- | Documentation/sound/designs/compress-offload.rst | 62 | ||||
| -rw-r--r-- | sound/core/compress_offload.c | 7 |
2 files changed, 41 insertions, 28 deletions
diff --git a/Documentation/sound/designs/compress-offload.rst b/Documentation/sound/designs/compress-offload.rst index 935f325dbc773..1ade8bb078eb3 100644 --- a/Documentation/sound/designs/compress-offload.rst +++ b/Documentation/sound/designs/compress-offload.rst @@ -256,32 +256,42 @@ Gapless Playback SM For Gapless, we move from running state to partial drain and back, along with setting of meta_data and signalling for next track :: - - +----------+ - compr_drain_notify() | | - +------------------------>| RUNNING | - | | | - | +----------+ - | | - | | - | | compr_next_track() - | | - | V - | +----------+ - | | | - | |NEXT_TRACK| - | | | - | +----------+ - | | - | | - | | compr_partial_drain() - | | - | V - | +----------+ - | | | - +------------------------ | PARTIAL_ | - | DRAIN | - +----------+ + +----------+ + compr_drain_notify() | | compr_set_params() iff next-track set. + +------------------------>| RUNNING |----------------------+ + | | | | + | +----------+ | + | | | + | | | + | | compr_next_track() | + | | V + | V | + | +----------+ | + | compr_partial_drain | | | + | +------------------|NEXT_TRACK| | + | | | | | + | | +----------+ | + | | | | + | | +----------------------------+ + | | | compr_set_params() + | V | + | | V + | | +----------+ + | | | | + | | | SETUP | + | | | | + | | +----------+ + | | | + | +-----------------------+ + | | + | | compr_partial_drain() + | | + | V + | +----------+ + | | | + +------------------------ | PARTIAL_ | + | DRAIN | + +----------+ Not supported ============= diff --git a/sound/core/compress_offload.c b/sound/core/compress_offload.c index 243acad89fd3b..1a3e5154bedcf 100644 --- a/sound/core/compress_offload.c +++ b/sound/core/compress_offload.c @@ -294,6 +294,9 @@ static ssize_t snd_compr_write(struct file *f, const char __user *buf, case SNDRV_PCM_STATE_SETUP: case SNDRV_PCM_STATE_PREPARED: case SNDRV_PCM_STATE_RUNNING: + /* Make sure next track params are set before writing new data */ + if (stream->next_track) + return -EPERM; break; default: mutex_unlock(&stream->device->lock); @@ -589,7 +592,8 @@ snd_compr_set_params(struct snd_compr_stream *stream, unsigned long arg) struct snd_compr_params *params; int retval; - if (stream->runtime->state == SNDRV_PCM_STATE_OPEN) { + if (stream->runtime->state == SNDRV_PCM_STATE_OPEN || + (stream->runtime->state == SNDRV_PCM_STATE_RUNNING && stream->next_track)) { /* * we should allow parameter change only when stream has been * opened not in other cases @@ -956,7 +960,6 @@ static int snd_compr_partial_drain(struct snd_compr_stream *stream) return retval; } - stream->next_track = false; return snd_compress_wait_for_drain(stream); } |