[alsa-devel] [ANNOUNCE] 2019 Linux Audio miniconference

[alsa-devel] [ANNOUNCE] 2019 Linux Audio miniconference

[Mark Brown]

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Hi,

As in previous years we're going to have an audio miniconference so we can
get together and talk through issues, especially design decisions, face to
face.  This year's event will be held on October 31st in Lyon, France,
the day after ELC-E.  This will be held at the Lyon Convention Center (the
ELC-E venue) and will be free of charge to attend, generously
sponsored by Intel.

Thus far for the agenda we have:

 - Use case management enhancements (Curtis)
 - DSP framework integration (Liam?)
 - Soundwire status (Pierre?)
 - Componentisation status/plans (Me)

As with previous years let's pull together an agenda through a mailing
list discussion - if people could reply to this mail with any topics
they'd like to discuss we can take it from there.  Of course if we can
sort things out more quickly via the mailing list that's even better!

If you're planning to attend please fill out the form here:

    https://docs.google.com/forms/d/e/1FAIpQLSd6FV-tWYZ1fHlCmyzQhG98OtYH9W9GX-1dQ88mnLxVRGyPww/viewform?usp=sf_link

This event will be covered by the same code of conduct as ELC-E.

Thanks again to Intel for supporting this event.

Thanks,
Mark

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Re: [alsa-devel] [ANNOUNCE] 2019 Linux Audio miniconference

[Daniel Baluta]

On Wed, Oct 9, 2019 at 9:15 PM Mark Brown <broonie@kernel.org> wrote:
>
> Hi,
>
> As in previous years we're going to have an audio miniconference so we can
> get together and talk through issues, especially design decisions, face to
> face.  This year's event will be held on October 31st in Lyon, France,
> the day after ELC-E.  This will be held at the Lyon Convention Center (the
> ELC-E venue) and will be free of charge to attend, generously
> sponsored by Intel.
>
> Thus far for the agenda we have:
>
>  - Use case management enhancements (Curtis)
>  - DSP framework integration (Liam?)
>  - Soundwire status (Pierre?)
>  - Componentisation status/plans (Me)

Hi Mark,

Thanks for taking care of this.

My topics:

- SOF driver: ACPI / DT unification
- SOF driver: Handling built-in driver use case

>
> As with previous years let's pull together an agenda through a mailing
> list discussion - if people could reply to this mail with any topics
> they'd like to discuss we can take it from there.  Of course if we can
> sort things out more quickly via the mailing list that's even better!
>
> If you're planning to attend please fill out the form here:
>
>     https://docs.google.com/forms/d/e/1FAIpQLSd6FV-tWYZ1fHlCmyzQhG98OtYH9W9GX-1dQ88mnLxVRGyPww/viewform?usp=sf_link
>
> This event will be covered by the same code of conduct as ELC-E.
>
> Thanks again to Intel for supporting this event.
>
> Thanks,
> Mark
> _______________________________________________
> Alsa-devel mailing list
> Alsa-devel@alsa-project.org
> https://mailman.alsa-project.org/mailman/listinfo/alsa-devel
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Re: [alsa-devel] [ANNOUNCE] 2019 Linux Audio miniconference

[Pierre-Louis Bossart]

On 10/9/19 1:13 PM, Mark Brown wrote:
> Hi,
> 
> As in previous years we're going to have an audio miniconference so we can
> get together and talk through issues, especially design decisions, face to
> face.  This year's event will be held on October 31st in Lyon, France,
> the day after ELC-E.  This will be held at the Lyon Convention Center (the
> ELC-E venue) and will be free of charge to attend, generously
> sponsored by Intel.
> 
> Thus far for the agenda we have:
> 
>   - Use case management enhancements (Curtis)
>   - DSP framework integration (Liam?)
>   - Soundwire status (Pierre?)

I am unfortunately not going to make it this year due to conflicts.

I will repost the 50-odd SoundWire patches we have when Vinod is back at 
his desk. For now we have most of the issues ironed out, with all known 
race conditions sorted out and with audio streaming to/from SoundWire 
links on CometLake, IceLake and TigerLake, with 4 different codecs from 
Realtek supported. We are trying to clean-up the last suspend/resume 
issues in collaboration with Realtek.

The latest code is here if anyone is interested:

https://github.com/thesofproject/linux/tree/integration/soundwire-latest

The only big topic is the multi-cpu support. We will need to support 
playback synchronized on multiple amplifiers/speakers, and our plan was 
to create a dailink that connect 2 CPU dais (possibly dealing with 
different links) to 2 codec DAIs.

The other interesting topic is the likely mix of SoundWire, I2S and yes 
HDaudio links for some platforms. This will make the autodetection a bit 
complex, not to mention all the possible topology variants. Ideally we 
should limit this complexity by exposing different cards for the 
different links with Ranjani's work on MFD.

We are also planning to try and use the Up Extreme board which exposes 2 
SoundWire links on the 40-pin connector, this will make it simpler for 
developers to get access to an open SoundWire-enabled platform and 
extend the pool of codecs supported, as we did with Minnow and Up boards.

-Pierre
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Re: [alsa-devel] [ANNOUNCE] 2019 Linux Audio miniconference

[Mark Brown]

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On Wed, Oct 09, 2019 at 09:48:14PM +0300, Daniel Baluta wrote:
> On Wed, Oct 9, 2019 at 9:15 PM Mark Brown <broonie@kernel.org> wrote:

> My topics:

I'll add these to the agenda.

> - SOF driver: ACPI / DT unification

Are there concrete plans to discuss here or is this more of a
"what are we doing" kind of thing?  ACPI standardization has been
an issue :/

> - SOF driver: Handling built-in driver use case

What's the issue here?

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Re: [alsa-devel] [ANNOUNCE] 2019 Linux Audio miniconference

[Pierre-Louis Bossart]

On 10/10/19 10:57 AM, Mark Brown wrote:
> On Wed, Oct 09, 2019 at 09:48:14PM +0300, Daniel Baluta wrote:
>> On Wed, Oct 9, 2019 at 9:15 PM Mark Brown <broonie@kernel.org> wrote:
> 
>> My topics:
> 
> I'll add these to the agenda.
> 
>> - SOF driver: ACPI / DT unification
> 
> Are there concrete plans to discuss here or is this more of a
> "what are we doing" kind of thing?  ACPI standardization has been
> an issue :/

I took this agenda item as "how machine drivers are handled in SOF".

Currently the core creates a platform device which will result in a 
machine driver being probe and the card created. This is mainly due to 
the lack of 'machine device' in existing DSDT tables. DT has explicit 
support for machine drivers, so we need to have a solution that caters 
to both.

> 
>> - SOF driver: Handling built-in driver use case
> 
> What's the issue here?

The SOF driver (or any existing driver with closed-source firmware) will 
not work when compiled as built-in due to the request_firmware() 
dependency. This wasn't too much of an issue for Intel so far, but for 
i.MX platforms it's quite common to have no modules.

Daniel, did I get things right?
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Re: [alsa-devel] [ANNOUNCE] 2019 Linux Audio miniconference

[Daniel Baluta]

On Thu, Oct 10, 2019 at 10:21 PM Pierre-Louis Bossart
<pierre-louis.bossart@linux.intel.com> wrote:
>
>
>
> On 10/10/19 10:57 AM, Mark Brown wrote:
> > On Wed, Oct 09, 2019 at 09:48:14PM +0300, Daniel Baluta wrote:
> >> On Wed, Oct 9, 2019 at 9:15 PM Mark Brown <broonie@kernel.org> wrote:
> >
> >> My topics:
> >
> > I'll add these to the agenda.
> >
> >> - SOF driver: ACPI / DT unification
> >
> > Are there concrete plans to discuss here or is this more of a
> > "what are we doing" kind of thing?  ACPI standardization has been
> > an issue :/
>
> I took this agenda item as "how machine drivers are handled in SOF".
>
> Currently the core creates a platform device which will result in a
> machine driver being probe and the card created. This is mainly due to
> the lack of 'machine device' in existing DSDT tables. DT has explicit
> support for machine drivers, so we need to have a solution that caters
> to both.
>
> >
> >> - SOF driver: Handling built-in driver use case
> >
> > What's the issue here?
>
> The SOF driver (or any existing driver with closed-source firmware) will
> not work when compiled as built-in due to the request_firmware()
> dependency. This wasn't too much of an issue for Intel so far, but for
> i.MX platforms it's quite common to have no modules.
>
> Daniel, did I get things right?

Yes, thanks for jumping in! This is exactly what I was thinking of.

Daniel.
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Re: [alsa-devel] [ANNOUNCE] 2019 Linux Audio miniconference

[Liam Girdwood]

On Wed, 2019-10-09 at 19:13 +0100, Mark Brown wrote:
> Hi,
> 
> As in previous years we're going to have an audio miniconference so
> we can
> get together and talk through issues, especially design decisions,
> face to
> face.  This year's event will be held on October 31st in Lyon,
> France,
> the day after ELC-E.  This will be held at the Lyon Convention Center
> (the
> ELC-E venue) and will be free of charge to attend, generously
> sponsored by Intel.
> 
> Thus far for the agenda we have:
> 
>  - Use case management enhancements (Curtis)
>  - DSP framework integration (Liam?)
>  - Soundwire status (Pierre?)
>  - Componentisation status/plans (Me)

Audio Virtualisation. (Me).

Liam


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Re: [alsa-devel] [ANNOUNCE] 2019 Linux Audio miniconference

[Curtis Malainey]

Are we going to get a whatsApp chat going beforehand again like last year?

On Mon, Oct 14, 2019 at 12:47 PM Liam Girdwood <
liam.r.girdwood@linux.intel.com> wrote:

> On Wed, 2019-10-09 at 19:13 +0100, Mark Brown wrote:
> > Hi,
> >
> > As in previous years we're going to have an audio miniconference so
> > we can
> > get together and talk through issues, especially design decisions,
> > face to
> > face.  This year's event will be held on October 31st in Lyon,
> > France,
> > the day after ELC-E.  This will be held at the Lyon Convention Center
> > (the
> > ELC-E venue) and will be free of charge to attend, generously
> > sponsored by Intel.
> >
> > Thus far for the agenda we have:
> >
> >  - Use case management enhancements (Curtis)
> >  - DSP framework integration (Liam?)
> >  - Soundwire status (Pierre?)
> >  - Componentisation status/plans (Me)
>
> Audio Virtualisation. (Me).
>
> Liam
>
>
>
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Re: [alsa-devel] [ANNOUNCE] 2019 Linux Audio miniconference

[Mark Brown]

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On Mon, Oct 14, 2019 at 08:47:07PM +0100, Liam Girdwood wrote:
> On Wed, 2019-10-09 at 19:13 +0100, Mark Brown wrote:

> > Thus far for the agenda we have:

> >  - Use case management enhancements (Curtis)
> >  - DSP framework integration (Liam?)
> >  - Soundwire status (Pierre?)
> >  - Componentisation status/plans (Me)

> Audio Virtualisation. (Me).

Sure, I'll add that.

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Re: [alsa-devel] [ANNOUNCE] 2019 Linux Audio miniconference

[Mark Brown]

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On Mon, Oct 14, 2019 at 01:16:40PM -0700, Curtis Malainey wrote:

> Are we going to get a whatsApp chat going beforehand again like last year?

Seems sensible, will ping off-list nearer the time.

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[alsa-devel] [ANNOUNCE] 2019 Linux Audio miniconference

[Mark Brown]

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Hi,

As in previous years we're going to have an audio miniconference so we can
get together and talk through issues, especially design decisions, face to
face.  This year's event will be held on October 31st in Lyon, France,
the day after ELC-E.  This will be held at the Lyon Convention Center (the
ELC-E venue) and will be free of charge to attend, generously
sponsored by Intel.

Thus far for the agenda we have is:

 - Use case management enhancements (Curtis)
 - DSP framework integration (Liam)
  - SOF integration with ACPI and DT (Daniel)
  - SOF support for non-modular drivers (Daniel)
 - Soundwire status (Liam?)
  - Multi-CPU support
  - Mixing with HDA/I2S in a single system
 - Virtualization (Liam)
 - Componentisation status/plans (Me)

As with previous years let's pull together an agenda through a mailing
list discussion - if people could reply to this mail with any topics
they'd like to discuss we can take it from there.  Of course if we can
sort things out more quickly via the mailing list that's even better!

If you're planning to attend please fill out the form here:

    https://docs.google.com/forms/d/e/1FAIpQLSd6FV-tWYZ1fHlCmyzQhG98OtYH9W9GX-1dQ88mnLxVRGyPww/viewform?usp=sf_link

This event will be covered by the same code of conduct as ELC-E.

Thanks again to Intel for supporting this event.

Thanks,
Mark

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Re: [alsa-devel] [ANNOUNCE] 2019 Linux Audio miniconference

[Jerome Brunet]

On Tue 22 Oct 2019 at 20:59, Mark Brown <broonie@kernel.org> wrote:

> Hi,
>
> As in previous years we're going to have an audio miniconference so we can
> get together and talk through issues, especially design decisions, face to
> face.  This year's event will be held on October 31st in Lyon, France,
> the day after ELC-E.  This will be held at the Lyon Convention Center (the
> ELC-E venue) and will be free of charge to attend, generously
> sponsored by Intel.
>
> Thus far for the agenda we have is:
>
>  - Use case management enhancements (Curtis)
>  - DSP framework integration (Liam)
>   - SOF integration with ACPI and DT (Daniel)
>   - SOF support for non-modular drivers (Daniel)
>  - Soundwire status (Liam?)
>   - Multi-CPU support
>   - Mixing with HDA/I2S in a single system
>  - Virtualization (Liam)
>  - Componentisation status/plans (Me)

I don't have a lot of experience with ASoC but I'd be happy to present
some of use cases I struggled with while adding support for the Amlogic
SoCs. Maybe this could serve as quick introduction to your part on
componentisation ?

>
> As with previous years let's pull together an agenda through a mailing
> list discussion - if people could reply to this mail with any topics
> they'd like to discuss we can take it from there.  Of course if we can
> sort things out more quickly via the mailing list that's even better!
>
> If you're planning to attend please fill out the form here:
>
>     https://docs.google.com/forms/d/e/1FAIpQLSd6FV-tWYZ1fHlCmyzQhG98OtYH9W9GX-1dQ88mnLxVRGyPww/viewform?usp=sf_link
>
> This event will be covered by the same code of conduct as ELC-E.
>
> Thanks again to Intel for supporting this event.
>
> Thanks,
> Mark
> _______________________________________________
> Alsa-devel mailing list
> Alsa-devel@alsa-project.org
> https://mailman.alsa-project.org/mailman/listinfo/alsa-devel

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Re: [alsa-devel] [ANNOUNCE] 2019 Linux Audio miniconference

[Mark Brown]

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On Wed, Oct 23, 2019 at 11:20:40AM +0200, Jerome Brunet wrote:

> I don't have a lot of experience with ASoC but I'd be happy to present
> some of use cases I struggled with while adding support for the Amlogic
> SoCs. Maybe this could serve as quick introduction to your part on
> componentisation ?

Ah, sorry - you had mentioned this before and I'd added it to the wrong
set of notes.  Yes, I think this'd be a good topic, let's add it.

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Re: [alsa-devel] [ANNOUNCE] 2019 Linux Audio miniconference

[Patrick Lai]

On 10/22/19 11:59 AM, Mark Brown wrote:
> Hi,

> 
> As with previous years let's pull together an agenda through a mailing
> list discussion - if people could reply to this mail with any topics
> they'd like to discuss we can take it from there.  Of course if we can
> sort things out more quickly via the mailing list that's even better!

1. Gapless playback handling between two playbacks with different format
2. Passing timestamp along with buffer for both playback and capture
3. PCM device volume control
4. Unified audio graph building across multiple subsystems

Thanks
Patrick

-- 
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a Linux Foundation Collaborative Project
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Re: [alsa-devel] [ANNOUNCE] 2019 Linux Audio miniconference

[Pierre-Louis Bossart]

On 10/24/19 9:20 AM, Patrick Lai wrote:
> On 10/22/19 11:59 AM, Mark Brown wrote:
>> Hi,
> 
>>
>> As with previous years let's pull together an agenda through a mailing
>> list discussion - if people could reply to this mail with any topics
>> they'd like to discuss we can take it from there.  Of course if we can
>> sort things out more quickly via the mailing list that's even better!
> 
> 1. Gapless playback handling between two playbacks with different format

did you mean compressed formats?

> 2. Passing timestamp along with buffer for both playback and capture
> 3. PCM device volume control
> 4. Unified audio graph building across multiple subsystems
> 
> Thanks
> Patrick
> 

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Re: [alsa-devel] [ANNOUNCE] 2019 Linux Audio miniconference

[Mark Brown]

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On Thu, Oct 24, 2019 at 07:20:02AM -0700, Patrick Lai wrote:

> 1. Gapless playback handling between two playbacks with different format
> 2. Passing timestamp along with buffer for both playback and capture
> 3. PCM device volume control
> 4. Unified audio graph building across multiple subsystems

OK, let's add these.

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Re: [alsa-devel] [ANNOUNCE] 2019 Linux Audio miniconference

[Vinod Koul]

On 24-10-19, 09:31, Pierre-Louis Bossart wrote:
> On 10/24/19 9:20 AM, Patrick Lai wrote:
> > On 10/22/19 11:59 AM, Mark Brown wrote:
> > > Hi,
> > 
> > > 
> > > As with previous years let's pull together an agenda through a mailing
> > > list discussion - if people could reply to this mail with any topics
> > > they'd like to discuss we can take it from there.  Of course if we can
> > > sort things out more quickly via the mailing list that's even better!
> > 
> > 1. Gapless playback handling between two playbacks with different format
> 
> did you mean compressed formats?

Yes this is for compressed formats. So, we do not allow users to set
parameters for gapless playback as the assumption is that we are in
album with same parameters for the subsequent tracks to be played.

But in case of some codecs like wma (and flac iirc) there can be changes
to next track using different wma formats which warrants change in
params.

Question is if this should be allowed and if so we need to propose a
change in API for this

> > 2. Passing timestamp along with buffer for both playback and capture
> > 3. PCM device volume control
> > 4. Unified audio graph building across multiple subsystems
> > 
> > Thanks
> > Patrick
> > 
> 
> _______________________________________________
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> Alsa-devel@alsa-project.org
> https://mailman.alsa-project.org/mailman/listinfo/alsa-devel

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Re: [alsa-devel] [ANNOUNCE] 2019 Linux Audio miniconference

[Vinod Koul]

On 09-10-19, 14:16, Pierre-Louis Bossart wrote:
> 
> 
> On 10/9/19 1:13 PM, Mark Brown wrote:
> > Hi,
> > 
> > As in previous years we're going to have an audio miniconference so we can
> > get together and talk through issues, especially design decisions, face to
> > face.  This year's event will be held on October 31st in Lyon, France,
> > the day after ELC-E.  This will be held at the Lyon Convention Center (the
> > ELC-E venue) and will be free of charge to attend, generously
> > sponsored by Intel.
> > 
> > Thus far for the agenda we have:
> > 
> >   - Use case management enhancements (Curtis)
> >   - DSP framework integration (Liam?)
> >   - Soundwire status (Pierre?)
> 
> I am unfortunately not going to make it this year due to conflicts.
> 
> I will repost the 50-odd SoundWire patches we have when Vinod is back at his
> desk. For now we have most of the issues ironed out, with all known race
> conditions sorted out and with audio streaming to/from SoundWire links on
> CometLake, IceLake and TigerLake, with 4 different codecs from Realtek
> supported. We are trying to clean-up the last suspend/resume issues in
> collaboration with Realtek.

Apart from x86 world, on arm side support for QC controller is on it way
to upstream (core already supports DT) and we did a demo on Dragon Board
RB3  at Connect SAN19 which uses SoundWire to talk to codec. Srini has
posted codec driver as well as master driver on ML, hopefully we will
have that merged before next merge window.

-- 
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Re: [alsa-devel] [ANNOUNCE] 2019 Linux Audio miniconference

[Pierre-Louis Bossart]

On 10/25/19 4:45 AM, Vinod Koul wrote:
> On 24-10-19, 09:31, Pierre-Louis Bossart wrote:
>> On 10/24/19 9:20 AM, Patrick Lai wrote:
>>> On 10/22/19 11:59 AM, Mark Brown wrote:
>>>> Hi,
>>>
>>>>
>>>> As with previous years let's pull together an agenda through a mailing
>>>> list discussion - if people could reply to this mail with any topics
>>>> they'd like to discuss we can take it from there.  Of course if we can
>>>> sort things out more quickly via the mailing list that's even better!
>>>
>>> 1. Gapless playback handling between two playbacks with different format
>>
>> did you mean compressed formats?
> 
> Yes this is for compressed formats. So, we do not allow users to set
> parameters for gapless playback as the assumption is that we are in
> album with same parameters for the subsequent tracks to be played.
> 
> But in case of some codecs like wma (and flac iirc) there can be changes
> to next track using different wma formats which warrants change in
> params.
> 
> Question is if this should be allowed and if so we need to propose a
> change in API for this

Gapless playback between compressed tracks needs to take the filter 
history/delay into account. The encoding/decoding process results in 
zero-values samples at the beginning of the file, and you need to flush 
the output likewise if you want all the samples. IIRC there is an I3D 
tag that tells you how many samples need to be skipped when you decode a 
new track, but I don't think this would work if the preceding track has 
a different format and hence filter delay/history.

E.g. if you assume the preceding track has a 256 sample filter delay, 
and if you switch to a track where the I3D tag tells you to remove the 
first 1024 samples, clearly something will go wrong. You'd need extra 
work in your firmware you have the two decoders co-exist for some time 
while you flush the previous history buffer and stitch it with the new 
samples. This leads to extra issues in terms of DSP resources.

And now that I think of it, I don't think we have a means to instantiate 
a second decoder on the same stream while it's running, you'd likely 
need two streams and a fancy stitching in your firmware.

And if you want this to work in Android, you'd also need extra streams 
in the HAL, and likely some changes in the media parts.

> 
>>> 2. Passing timestamp along with buffer for both playback and capture
>>> 3. PCM device volume control
>>> 4. Unified audio graph building across multiple subsystems
>>>
>>> Thanks
>>> Patrick
>>>
>>
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> 
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Re: [alsa-devel] [ANNOUNCE] 2019 Linux Audio miniconference

[Patrick Lai]

On 10/24/19 7:31 AM, Pierre-Louis Bossart wrote:
> On 10/24/19 9:20 AM, Patrick Lai wrote:
>> On 10/22/19 11:59 AM, Mark Brown wrote:
>>> Hi,
>>
>>>
>>> As with previous years let's pull together an agenda through a mailing
>>> list discussion - if people could reply to this mail with any topics
>>> they'd like to discuss we can take it from there.  Of course if we can
>>> sort things out more quickly via the mailing list that's even better!
>>
>> 1. Gapless playback handling between two playbacks with different format
> 
> did you mean compressed formats?

Yes, compress format

Thanks
Patrick

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Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project
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