On 6/29/2020 9:50 AM, Vinod Koul wrote:
> So we had some discussions of the stream states, so I thought it is a
> good idea to document the state transitions, so add it documentation
>
> Reviewed-by: Charles Keepax <[email protected]>
> Signed-off-by: Vinod Koul <[email protected]>
> ---
> .../sound/designs/compress-offload.rst | 51 +++++++++++++++++++
> 1 file changed, 51 insertions(+)
>
> diff --git a/Documentation/sound/designs/compress-offload.rst b/Documentation/sound/designs/compress-offload.rst
> index ad4bfbdacc83..b6e9025ae105 100644
> --- a/Documentation/sound/designs/compress-offload.rst
> +++ b/Documentation/sound/designs/compress-offload.rst
> @@ -151,6 +151,57 @@ Modifications include:
> - Addition of encoding options when required (derived from OpenMAX IL)
> - Addition of rateControlSupported (missing in OpenMAX AL)
>
> +State Machine
> +=============
> +
> +The compressed audio stream state machine is described below ::
> +
> + +----------+
> + | |
> + | OPEN |
> + | |
> + +----------+
> + |
> + |
> + | compr_set_params()
> + |
> + v
> + compr_free() +----------+
> + +------------------------------------| |
> + | | SETUP |
> + | +------------------------>| |<-------------------------+
> + | | compr_drain_notify() +----------+ |
> + | | or ^ |
> + | | compr_stop() | |
> + | | | compr_write() |
> + | | | |
> + | | | |
> + | | +----------+ |
> + | | | | compr_free() |
> + | | | PREPARE |---------------> A |
> + | | | | |
> + | | +----------+ |
> + | | | |
> + | | | |
> + | | | compr_start() |
> + | | | |
> + | | v |
> + | +----------+ +----------+ |
> + | | | compr_drain() | | compr_stop() |
> + | | DRAIN |<-------------------| RUNNING |--------------------------+
> + | | | | | |
> + | +----------+ +----------+ |
> + | | ^ |
> + | A | | |
> + | | compr_pause() | | compr_resume() |
> + | | | | |
> + | v v | |
> + | +----------+ +----------+ |
> + | | | | | compr_stop() |
> + +--->| FREE | | PAUSE |---------------------------+
> + | | | |
> + +----------+ +----------+
> +
>
> Gapless Playback
> ================
>
Line containing compr_free (between SETUP and FREE) seems to be misaligned?
If you move prepare to the left and drain in place of drain, it feels
like you won't need this weird indirection with A
Something like:
>> + v
>> + compr_free() +----------+
>> + +------------------------------------| |
>> + | | SETUP |
>> + | +------------------------>| |<-------------------------+
>> + | | compr_write() +----------+ |
>> + | | ^ |
>> + | | | compr_drain_notify() or |
>> + | | | compr_stop() |
>> + | | | |
>> + | | | |
>> + | | +----------+ |
>> + | | | | |
>> + | | | DRAIN | |
>> + | | | | |
>> + | | +----------+ |
>> + | | ^ |
>> + | | | |
>> + | | | compr_drain() |
>> + | | | |
>> + | | | |
>> + | +----------+ +----------+ |
>> + | | | compr_start() | | compr_stop() |
>> + | | PREPARE |------------------->| RUNNING |--------------------------+
>> + | | | | | |
>> + | +----------+ +----------+ |
>> + | | | ^ |
>> + | | compr_free() | | |
>> + | | compr_pause() | | compr_resume() |
>> + | | | | |
>> + | v v | |
>> + | +----------+ +----------+ |
>> + | | | | | compr_stop() |
>> + +--->| FREE | | PAUSE |---------------------------+
>> + | | | |
>> + +----------+ +----------+
>> +
but this makes me question PREPARE state, how do you enter it?
Hi Amadeusz,
On 29-06-20, 11:05, Amadeusz Sławiński wrote:
>
>
> On 6/29/2020 9:50 AM, Vinod Koul wrote:
> > So we had some discussions of the stream states, so I thought it is a
> > good idea to document the state transitions, so add it documentation
> >
> > Reviewed-by: Charles Keepax <[email protected]>
> > Signed-off-by: Vinod Koul <[email protected]>
> > ---
> > .../sound/designs/compress-offload.rst | 51 +++++++++++++++++++
> > 1 file changed, 51 insertions(+)
> >
> > diff --git a/Documentation/sound/designs/compress-offload.rst b/Documentation/sound/designs/compress-offload.rst
> > index ad4bfbdacc83..b6e9025ae105 100644
> > --- a/Documentation/sound/designs/compress-offload.rst
> > +++ b/Documentation/sound/designs/compress-offload.rst
> > @@ -151,6 +151,57 @@ Modifications include:
> > - Addition of encoding options when required (derived from OpenMAX IL)
> > - Addition of rateControlSupported (missing in OpenMAX AL)
> > +State Machine
> > +=============
> > +
> > +The compressed audio stream state machine is described below ::
> > +
> > + +----------+
> > + | |
> > + | OPEN |
> > + | |
> > + +----------+
> > + |
> > + |
> > + | compr_set_params()
> > + |
> > + v
> > + compr_free() +----------+
> > + +------------------------------------| |
> > + | | SETUP |
> > + | +------------------------>| |<-------------------------+
> > + | | compr_drain_notify() +----------+ |
> > + | | or ^ |
> > + | | compr_stop() | |
> > + | | | compr_write() |
> > + | | | |
> > + | | | |
Not sure, this is not in the version I posted, arrow is from setup ->
prepare. See https://lore.kernel.org/alsa-devel/[email protected]/
I don't know how it got reversed in your version, maybe the MUA messed
up??
> > + | | +----------+ |
> > + | | | | compr_free() |
> > + | | | PREPARE |---------------> A |
> > + | | | | |
> > + | | +----------+ |
> > + | | | |
> > + | | | |
> > + | | | compr_start() |
> > + | | | |
> > + | | v |
> > + | +----------+ +----------+ |
> > + | | | compr_drain() | | compr_stop() |
> > + | | DRAIN |<-------------------| RUNNING |--------------------------+
> > + | | | | | |
> > + | +----------+ +----------+ |
> > + | | ^ |
> > + | A | | |
> > + | | compr_pause() | | compr_resume() |
> > + | | | | |
> > + | v v | |
> > + | +----------+ +----------+ |
> > + | | | | | compr_stop() |
> > + +--->| FREE | | PAUSE |---------------------------+
> > + | | | |
> > + +----------+ +----------+
> > +
> > Gapless Playback
> > ================
> >
>
> Line containing compr_free (between SETUP and FREE) seems to be misaligned?
not in the version I posted and see on lore
> If you move prepare to the left and drain in place of drain, it feels like
> you won't need this weird indirection with A
yeah that was a compromise to make it bit neater to me than adding
overlapping arrows...
> Something like:
>
> >> + v
> > > + compr_free() +----------+
> > > + +------------------------------------| |
> > > + | | SETUP |
> > > + | +------------------------>| |<-------------------------+
> > > + | | compr_write() +----------+ |
> > > + | | ^ |
> > > + | | | compr_drain_notify() or |
> > > + | | | compr_stop() |
> > > + | | | |
> > > + | | | |
> > > + | | +----------+ |
> > > + | | | | |
> > > + | | | DRAIN | |
> > > + | | | | |
> > > + | | +----------+ |
> > > + | | ^ |
> > > + | | | |
> > > + | | | compr_drain() |
> > > + | | | |
> > > + | | | |
> > > + | +----------+ +----------+ |
> > > + | | | compr_start() | | compr_stop() |
> > > + | | PREPARE |------------------->| RUNNING |--------------------------+
> > > + | | | | | |
> > > + | +----------+ +----------+ |
> > > + | | | ^ |
> > > + | | compr_free() | | |
> > > + | | compr_pause() | | compr_resume() |
> > > + | | | | |
> > > + | v v | |
> > > + | +----------+ +----------+ |
> > > + | | | | | compr_stop() |
> > > + +--->| FREE | | PAUSE |---------------------------+
> > > + | | | |
> > > + +----------+ +----------+
> > > +
>
> but this makes me question PREPARE state, how do you enter it?
a compr_write() moves from SETUP -> PREPARE. Fixing that above looks
better version of mine..
--
~Vinod