HDMI LPE audio on Intel Compute Stick 2nd Gen (CHT)

HDMI LPE audio on Intel Compute Stick 2nd Gen (CHT)

[Ian W MORRISON]

Hi Pierre,

I've just noticed that non of the kernels from v4.13 and up run on my
Intel Compute Stick (2nd gen Cherry Trail STK1AW32SC) unit and have
HDMI LPE audio working. Before I spend anytime looking into this can
you confirm if you have the same issue as I just want to rule out a
hardware malfunction with my unit first?

Thanks,
Ian

Re: HDMI LPE audio on Intel Compute Stick 2nd Gen (CHT)

[Pierre-Louis Bossart]

On 10/17/17 5:50 AM, Ian W MORRISON wrote:
> Hi Pierre,
> 
> I've just noticed that non of the kernels from v4.13 and up run on my
> Intel Compute Stick (2nd gen Cherry Trail STK1AW32SC) unit and have
> HDMI LPE audio working. Before I spend anytime looking into this can
> you confirm if you have the same issue as I just want to rule out a
> hardware malfunction with my unit first?

I have not tested HDMI in a while but I am not aware of any issues 
either. There were some patches recently to fix PulseAudio problems and 
I suppose some folks used a recent kernel?

Re: HDMI LPE audio on Intel Compute Stick 2nd Gen (CHT)

[Ian W MORRISON]

> I've just noticed that non of the kernels from v4.13 and up run on my
>> Intel Compute Stick (2nd gen Cherry Trail STK1AW32SC) unit and have
>> HDMI LPE audio working.
>>
>
> I have not tested HDMI in a while but I am not aware of any issues either.
> There were some patches recently to fix PulseAudio problems and I suppose
> some folks used a recent kernel?
>
>
It actually happened since v4.12 as now I get three HDMI LPE Audio devices
show up with 'aplay -l' rather than just one. Only 'device 2' works so if I
change the sink to use that device I get sound. So basically it can be
fixed in userland however I'm seeing others with different devices also
complaining how audio is broken and I think it is something that many users
don't know to fix. Is it worth looking into further or just leaving it as a
known issue?

Re: HDMI LPE audio on Intel Compute Stick 2nd Gen (CHT)

[Pierre-Louis Bossart]

On 10/20/17 8:45 AM, Ian W MORRISON wrote:
>> I've just noticed that non of the kernels from v4.13 and up run on my
>>> Intel Compute Stick (2nd gen Cherry Trail STK1AW32SC) unit and have
>>> HDMI LPE audio working.
>>>
>>
>> I have not tested HDMI in a while but I am not aware of any issues either.
>> There were some patches recently to fix PulseAudio problems and I suppose
>> some folks used a recent kernel?
>>
>>
> It actually happened since v4.12 as now I get three HDMI LPE Audio devices
> show up with 'aplay -l' rather than just one. Only 'device 2' works so if I
> change the sink to use that device I get sound. So basically it can be
> fixed in userland however I'm seeing others with different devices also
> complaining how audio is broken and I think it is something that many users
> don't know to fix. Is it worth looking into further or just leaving it as a
> known issue?

I don't think it's a bug, it's a feature...
The jack information tells you which device is connected/active, so 
userspace has all the data needed to select the right routing.

Re: HDMI LPE audio on Intel Compute Stick 2nd Gen (CHT)

[Takashi Iwai]

On Fri, 20 Oct 2017 17:54:45 +0200,
Pierre-Louis Bossart wrote:
> 
> On 10/20/17 8:45 AM, Ian W MORRISON wrote:
> >> I've just noticed that non of the kernels from v4.13 and up run on my
> >>> Intel Compute Stick (2nd gen Cherry Trail STK1AW32SC) unit and have
> >>> HDMI LPE audio working.
> >>>
> >>
> >> I have not tested HDMI in a while but I am not aware of any issues either.
> >> There were some patches recently to fix PulseAudio problems and I suppose
> >> some folks used a recent kernel?
> >>
> >>
> > It actually happened since v4.12 as now I get three HDMI LPE Audio devices
> > show up with 'aplay -l' rather than just one. Only 'device 2' works so if I
> > change the sink to use that device I get sound. So basically it can be
> > fixed in userland however I'm seeing others with different devices also
> > complaining how audio is broken and I think it is something that many users
> > don't know to fix. Is it worth looking into further or just leaving it as a
> > known issue?
> 
> I don't think it's a bug, it's a feature...
> The jack information tells you which device is connected/active, so
> userspace has all the data needed to select the right routing.

Right, it's a new feature that was recently added, for supporting
multiple HDMI/DPs.  The latest PA should be able to check the jack
detection of each port, so that it can switch to the actually
connected one.


Takashi

Re: HDMI LPE audio on Intel Compute Stick 2nd Gen (CHT)

[Ian W MORRISON]

On 21 October 2017 at 03:53, Takashi Iwai <tiwai@suse.de> wrote:

> On Fri, 20 Oct 2017 17:54:45 +0200,
> Pierre-Louis Bossart wrote:
> >
> > On 10/20/17 8:45 AM, Ian W MORRISON wrote:
> > >> I've just noticed that non of the kernels from v4.13 and up run on my
> > >>> Intel Compute Stick (2nd gen Cherry Trail STK1AW32SC) unit and have
> > >>> HDMI LPE audio working.
> > >>>
> > >>
> > >> I have not tested HDMI in a while but I am not aware of any issues
> either.
> > >> There were some patches recently to fix PulseAudio problems and I
> suppose
> > >> some folks used a recent kernel?
> > >>
> > >>
> > > It actually happened since v4.12 as now I get three HDMI LPE Audio
> devices
> > > show up with 'aplay -l' rather than just one. Only 'device 2' works so
> if I
> > > change the sink to use that device I get sound. So basically it can be
> > > fixed in userland however I'm seeing others with different devices also
> > > complaining how audio is broken and I think it is something that many
> users
> > > don't know to fix. Is it worth looking into further or just leaving it
> as a
> > > known issue?
> >
> > I don't think it's a bug, it's a feature...
> > The jack information tells you which device is connected/active, so
> > userspace has all the data needed to select the right routing.
>
> Right, it's a new feature that was recently added, for supporting
> multiple HDMI/DPs.  The latest PA should be able to check the jack
> detection of each port, so that it can switch to the actually
> connected one.
>
>
> Takashi
>

Thanks for the explanation. The PA package for Ubuntu is a bit behind (v8
for 16.04 LST and v10 for latest 17.10) so it will be easier for users just
to edit /etc/pulse/default.pa in the interim. But is there a way to stop
the multiple and repeating "Audio Port: ASoC: no backend DAIs enabled for
Audio Port" messages in dmesg from occurring without modifying the distro's
kernel?

Re: HDMI LPE audio on Intel Compute Stick 2nd Gen (CHT)

[Takashi Iwai]

On Sun, 22 Oct 2017 15:00:12 +0200,
Ian W MORRISON wrote:
> 
> On 21 October 2017 at 03:53, Takashi Iwai <tiwai@suse.de> wrote:
> 
> > On Fri, 20 Oct 2017 17:54:45 +0200,
> > Pierre-Louis Bossart wrote:
> > >
> > > On 10/20/17 8:45 AM, Ian W MORRISON wrote:
> > > >> I've just noticed that non of the kernels from v4.13 and up run on my
> > > >>> Intel Compute Stick (2nd gen Cherry Trail STK1AW32SC) unit and have
> > > >>> HDMI LPE audio working.
> > > >>>
> > > >>
> > > >> I have not tested HDMI in a while but I am not aware of any issues
> > either.
> > > >> There were some patches recently to fix PulseAudio problems and I
> > suppose
> > > >> some folks used a recent kernel?
> > > >>
> > > >>
> > > > It actually happened since v4.12 as now I get three HDMI LPE Audio
> > devices
> > > > show up with 'aplay -l' rather than just one. Only 'device 2' works so
> > if I
> > > > change the sink to use that device I get sound. So basically it can be
> > > > fixed in userland however I'm seeing others with different devices also
> > > > complaining how audio is broken and I think it is something that many
> > users
> > > > don't know to fix. Is it worth looking into further or just leaving it
> > as a
> > > > known issue?
> > >
> > > I don't think it's a bug, it's a feature...
> > > The jack information tells you which device is connected/active, so
> > > userspace has all the data needed to select the right routing.
> >
> > Right, it's a new feature that was recently added, for supporting
> > multiple HDMI/DPs.  The latest PA should be able to check the jack
> > detection of each port, so that it can switch to the actually
> > connected one.
> >
> >
> > Takashi
> >
> 
> Thanks for the explanation. The PA package for Ubuntu is a bit behind (v8
> for 16.04 LST and v10 for latest 17.10) so it will be easier for users just
> to edit /etc/pulse/default.pa in the interim. But is there a way to stop
> the multiple and repeating "Audio Port: ASoC: no backend DAIs enabled for
> Audio Port" messages in dmesg from occurring without modifying the distro's
> kernel?

The DAI backend has nothing to do with HDMI LPE audio.  It's from ASoC
Intel SST driver.  You need to set up the routing either via UCM or
manually.


Takashi

Re: HDMI LPE audio on Intel Compute Stick 2nd Gen (CHT)

[Pierre-Louis Bossart]

On 10/22/17 6:30 PM, Ian W MORRISON wrote:
> On 21 October 2017 at 03:53, Takashi Iwai <tiwai@suse.de> wrote:
> 
>> On Fri, 20 Oct 2017 17:54:45 +0200,
>> Pierre-Louis Bossart wrote:
>>>
>>> On 10/20/17 8:45 AM, Ian W MORRISON wrote:
>>>>> I've just noticed that non of the kernels from v4.13 and up run on my
>>>>>> Intel Compute Stick (2nd gen Cherry Trail STK1AW32SC) unit and have
>>>>>> HDMI LPE audio working.
>>>>>>
>>>>>
>>>>> I have not tested HDMI in a while but I am not aware of any issues
>> either.
>>>>> There were some patches recently to fix PulseAudio problems and I
>> suppose
>>>>> some folks used a recent kernel?
>>>>>
>>>>>
>>>> It actually happened since v4.12 as now I get three HDMI LPE Audio
>> devices
>>>> show up with 'aplay -l' rather than just one. Only 'device 2' works so
>> if I
>>>> change the sink to use that device I get sound. So basically it can be
>>>> fixed in userland however I'm seeing others with different devices also
>>>> complaining how audio is broken and I think it is something that many
>> users
>>>> don't know to fix. Is it worth looking into further or just leaving it
>> as a
>>>> known issue?
>>>
>>> I don't think it's a bug, it's a feature...
>>> The jack information tells you which device is connected/active, so
>>> userspace has all the data needed to select the right routing.
>>
>> Right, it's a new feature that was recently added, for supporting
>> multiple HDMI/DPs.  The latest PA should be able to check the jack
>> detection of each port, so that it can switch to the actually
>> connected one.
>>
>>
>> Takashi
>>
> 
> Thanks for the explanation. The PA package for Ubuntu is a bit behind (v8
> for 16.04 LST and v10 for latest 17.10) so it will be easier for users just
> to edit /etc/pulse/default.pa in the interim. But is there a way to stop
> the multiple and repeating "Audio Port: ASoC: no backend DAIs enabled for
> Audio Port" messages in dmesg from occurring without modifying the distro's
> kernel?

That issue comes from the mixer configuration (or lack thereof) or 
missing UCM files, it's not really a kernel issue.
We've talked in the past of moving existing UCM files to a new repo 
(with a clarified license) and adding the ones I maintained, it's likely 
to happen after we are done with the open-source firmware (SOF) 
integration which requires some plumbing to the life of distros easier.