[alsa-devel] [RFC] Fix for conflict of HDMI and SPDIF IEC958 controls

[Takashi Iwai]

At Mon, 15 Oct 2012 16:49:58 +0800,
Raymond Yau wrote:
> 
> 2012-10-15 下午4:35 於 "Takashi Iwai" <tiwai at suse.de> 寫道：
> >
> > At Mon, 15 Oct 2012 16:15:20 +0800,
> > Raymond Yau wrote:
> > >
> > > 2012-10-15 下午3:46 於 "Takashi Iwai" <tiwai at suse.de> 寫道：
> > > >
> > > > At Mon, 15 Oct 2012 10:31:50 +0800,
> > > > Raymond Yau wrote:
> > > > >
> > > > > 2012-10-12 下午11:19 於 "Takashi Iwai" <tiwai at suse.de> 寫道：
> > > > > >
> > > > > > Hi,
> > > > > >
> > > > > > there is a long-standing problem in HD-audio regarding IEC958
> > > > > > controls.  When both an SPDIF and an HDMI are created on the same
> > > > > > card (e.g. one from analog codec and one from graphics chip), the
> > > > > > driver assigns the IEC958 controls just with new indices, 0, 1,
> 2...
> > > > > >
> > > > > > The problem is that there is no way to connect between this index
> and
> > > > > > the actual PCM device.  Currently, alsa-lib HDA-Intel.conf has a
> fixed
> > > > > > configuration:
> > > > > >   spdif  -> IEC958 xxx index=0, PCM dev=1
> > > > > >   hdmi,0 -> IEC958 xxx index=0, PCM dev=3
> > > > > >   hdmi,1 -> IEC958 xxx index=1, PCM dev=7
> > > > > >   hdmi,2 -> IEC958 xxx index=2, PCM dev=8
> > > > > >   hdmi,3 -> IEC958 xxx index=3, PCM dev=9
> > > > > >
> > > > > > So obviously spdif and the first hdmi conflict.
> > > > > >
> > > > > > Basically this can be fixed by reassigning each IEC958 control
> with
> > > > > > the same device number corresponding to the PCM device.  That is,
> for
> > > > > > SPDIF, assign a control element with device=1, for HDMI,
> > > > > > device=3,7...
> > > > > > However, this obviously breaks the old configuration unless user
> > > > > > upgrades the alsa-lib configuration.  Thus this is no-go.
> > > > > >
> > > > > > Now here is a compromise: the IEC958 control for SPDIF is
> reassigned
> > > > > > to device=1 *only* when SPDIF and HDMI coexist.  Since the
> > > > > > configuration is anyway broken as is now in such a case, it's no
> big
> > > > > > deal to fix one side in an incompatible way.  (The reason why
> SPDIF
> > > > > > is re-assigned is that I guess majority of user require more HDMI
> than
> > > > > > SPDIF in such a configuration.)
> > > > > >
> > > > > > In addition, we need a fix in alsa-lib.  Also not for breaking the
> > > > > > compatibility with older kernel, we need some fallback check.  I
> did a
> > > > > > quick hack to alsa-lib conf code and added "skip_rest" option to
> the
> > > > > > hook element, so that only the first matching element is taken.
> > > > >
> > > > > how about those hdmi jack and iec958 on ad1989b?
> > > >
> > > > On AD codecs, all digital outputs are exposed as a single cloned
> > > > device with HDA_PCM_TYPE_SPDIF.
> > >
> > > how about ad1988b with nvidia codec ?
> >
> > Nvidia codec provides devices only with HDA_PCM_TYPE_HDMI, of course.
> >
> > > from user point of view , how can they differenitate hdmi jack is
> digital
> > > ouput and hdmi output ?
> >
> > The device 1 is from AD and the device 3 is from Nvidia codec, as you
> > can see below.  And this is exactly the case the conflict happens as I
> > mentioned in the original mail.
> 
> will your fix change the spdif of  those motherboard with ad1988b which
> have iec958 but no hdmi jack ?

It won't change anything unless both SPDIF and HDMI *devices* are
actually created.

> the current implementation does not expose the number of output streams
> supported by the hda controller
> 
> ich8 seem support 4 ouput streams , how many output streams supported by
> the nvidia controller

It's an irrelevant issue.  Don't mix up the problems.


> > Which is connected to what output, you can't know exactly unless you
> > compare the obtained ELD.  The HD-audio spec isn't good enough to
> > identify the actual output.
> 
> it seem that there is no presence detect on this codec

ELD has nothing to do with the presence detect bit.


Takashi


> Codec: Nvidia MCP77/78 HDMI
> Address: 3
> AFG Function Id: 0x1 (unsol 0)
> Vendor Id: 0x10de0002
> Subsystem Id: 0x10de0101
> Revision Id: 0x100000
> No Modem Function Group found
> Default PCM:
>     rates [0x0]:
>     bits [0x0]:
>     formats [0x0]:
> Default Amp-In caps: N/A
> Default Amp-Out caps: N/A
> GPIO: io=0, o=0, i=0, unsolicited=0, wake=0
> Node 0x04 [Audio Output] wcaps 0x211: Stereo Digital
>   Control: name="IEC958 Playback Con Mask", index=1, device=0
>   Control: name="IEC958 Playback Pro Mask", index=1, device=0
>   Control: name="IEC958 Playback Default", index=1, device=0
>   Control: name="IEC958 Playback Switch", index=1, device=0
>   Device: name="HDMI 0", type="HDMI", device=3
>   Converter: stream=0, channel=0
>   Digital:
>   Digital category: 0x0
>   PCM:
>     rates [0xc0]: 48000 88200
>     bits [0xf]: 8 16 20 24
>     formats [0x1]: PCM
> Node 0x05 [Pin Complex] wcaps 0x400381: Stereo Digital
>   Pincap 0x00000014: OUT Detect
>   Pin Default 0x18560110: [Jack] Digital Out at Int HDMI
>     Conn = Digital, Color = Unknown
>     DefAssociation = 0x1, Sequence = 0x0
>     Misc = NO_PRESENCE
>   Pin-ctls: 0x40: OUT
>   Unsolicited: tag=00, enabled=0
>   Connection: 1
>      0x04
> 
> >
> >
> > Takashi
> >
> >
> > > https://bugs.launchpad.net/ubuntu/+source/pulseaudio/+bug/881826
> > >
> > > **** List of PLAYBACK Hardware Devices ****
> > > card 0: NVidia [HDA NVidia], device 0: AD198x Analog [AD198x Analog]
> > >   Subdevices: 1/1
> > >   Subdevice #0: subdevice #0
> > > card 0: NVidia [HDA NVidia], device 1: AD198x Digital [AD198x Digital]
> > >   Subdevices: 1/1
> > >   Subdevice #0: subdevice #0
> > > card 0: NVidia [HDA NVidia], device 3: HDMI 0 [HDMI 0]
> > >   Subdevices: 1/1
> > >   Subdevice #0: subdevice #0