At Wed, 28 Mar 2007 11:58:50 -0600, Rob Franklin wrote: > > On 3/28/07, Takashi Iwai <tiwai@xxxxxxx> wrote: > > Hi, > > > > Please don't drop Cc to alsa-devel... > > > > At Wed, 28 Mar 2007 10:23:22 -0600, > > Rob Franklin wrote: > > > > > > On 3/28/07, Takashi Iwai <tiwai@xxxxxxx> wrote: > > > > At Tue, 27 Mar 2007 10:44:23 -0600, > > > > Rob Franklin wrote: > > > > > > > > > > On 3/27/07, Takashi Iwai <tiwai@xxxxxxx> wrote: > > > > > > At Tue, 27 Mar 2007 08:49:05 -0600, > > > > > > Rob Franklin wrote: > > > > > > > > > > > > > > Hi All, > > > > > > > > > > > > > > I posted a question a couple of weeks ago to the alsa-users list > > > > > > > (Can't get spdif working with ALSA and FC6 on ECS L4S5MG/651+ > > > > > > > motherboard), but never got a response. > > > > > > > > > > > > > > I have been looking at the ALSA source code for the AC'97 codec on my > > > > > > > board (CMI9738) and the source code for the intel8x0 driver (for my > > > > > > > SiS 7012). However, as far as I can tell from looking at the source, > > > > > > > S/PDIF is not enabled/supported for this combination of devices. > > > > > > > Additionally, Googling around I haven't found any mention of people > > > > > > > getting spdif working with ALSA and a CM9738 / SiS7012 combo. > > > > > > > > > > > > > > I am wondering whether anyone on the developer list can confirm that > > > > > > > this is the case. Also, if this is the case can someone give me an > > > > > > > idea of what would be required to get this working. The system is > > > > > > > setup with dual boot and so I could grab some of the values from > > > > > > > windows using a PCI sniffer, and I might be able to do some hacking on > > > > > > > the source code and submit a patch if someone could help guide me in > > > > > > > the right direction. > > > > > > > > > > > > Are you sure it's CM9738? AFAIK, CM9738 doesn't support SPDIF at > > > > > > all, but CM9739 does... > > > > > > > > > > > That was my first thought too, but I pulled open the case last night > > > > > and verified that it was indeed a 9738. The download page from the > > > > > motherboard manufacturer has a driver for CMI9738 and a CMI9738/9739 > > > > > driver (http://www.ecsusa.com/downloads/drivers_sound.html). I am > > > > > wondering if there are two different versions of this chip. > > > > > > > > > > Here is the output from lspci -vv for the sound device: > > > > > > > > > > 00:02.7 Multimedia audio controller: Silicon Integrated Systems [SiS] > > > > > AC'97 Sound Controller (rev a0) > > > > > Subsystem: Elitegroup Computer Systems Unknown device 0a44 > > > > > Control: I/O+ Mem- BusMaster+ SpecCycle- MemWINV- VGASnoop- > > > > > ParErr- Stepping- SERR- FastB2B- > > > > > Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium > > > > > >TAbort- <TAbort- <MAbort- >SERR- <PERR- > > > > > Latency: 32 (13000ns min, 2750ns max) > > > > > Interrupt: pin C routed to IRQ 22 > > > > > Region 0: I/O ports at d000 [size=256] > > > > > Region 1: I/O ports at d400 [size=128] > > > > > Capabilities: <access denied> > > > > > > > > > > One thought that I had was to force the AC'97 driver to detect the > > > > > chip as a 9739 instead of a 9738 to see whether my 9738 can work as a > > > > > 9739. But I'm not sure how to do that short of modifying the source > > > > > code and recompiling the kernel module. > > > > > > > > First check whether its codec id is CMI9738, see > > > > /proc/asound/card0/codec97#0/* files. If it's really CM9738, you can > > > > hack pci/ac97/ac97_codec.c to replace patch_cm9738 with patch_cm9739 > > > > in snd_ac97_codec_ids[]. > > > > > > > Here are the first couple of lines from /proc/asound/card0/codec97#0/ac97#0-0 : > > > > > > 0-0/0: C-Media Electronics CMI9738 > > > > > > PCI Subsys Vendor: 0x1019 > > > PCI Subsys Device: 0x0a44 > > > > > > Last night I hacked the ac97_codec.c and recompiled snd-ac97-codec.ko, > > > and now the file reads > > > > > > 0-0/0: C-Media Electronics -- rob CMI9739 > > > > > > Everything seems to be working the same as it was before, and I can > > > get stereo sound from the line-out jack just fine. However, when I > > > try to play back sound using the spdif I get the following: > > > > > > $ aplay -D plug:iec958 ac3_48khz_diatonis_soal.ac3 > > > ALSA lib setup.c:555:(add_elem) Cannot obtain info for CTL elem > > > (MIXER,'IEC958 Playback Default',0,0,0): No such file or directory > > > > I guess the control element wasn't created indeed because of lack of > > SPDIF feature on the codec. > > > > patch_cm9739() checks the availability of SPDIF bit (SPCV) and turn > > off the whole SPDIF feature if the bit isn't set. You can avoid that > > check just for testing. > > > > If this doesn't work, the possible situation is that the SPDIF is > > transmitted directly from the controller chip without AC97 codec. > > Unfortunately, we have no hardware information about SIS7012, so don't > > know whether it's even possible, and how to control it. > > > > > Is there a script I need to run or file I need to update my list of > > > CTLs (I have seen references to alsaconf and snddev on the web but > > > neither seems to be included with my FC5 install of alsa-utils)? > > > > % alsactl -f somefile store > > > > > Also, is there any easy way to reload the snd-ac97-codec.ko module. I > > > tried removing the modules with "rmmod snd-ac97-codec" and "modprobe > > > snd-ac97-codec". The module came out ok, but I got a bunch of errors > > > like this when I tried to reinsert the modules: > > > > > > Mar 27 21:16:46 XXXX kernel: snd_ac97_codec: Unknown symbol snd_info_register > > > Mar 27 21:16:46 XXXX kernel: snd_ac97_codec: disagrees about version > > > of symbol snd_ctl_add > > > > > > So right now I am rebooting the machine every time I want to replace > > > snd-ac97-codec. > > > > Seems that you still have the old modules on memory while installing > > the new modules. First unload all snd related modules, then reload > > again. > > > > Otherwise, something wrong with the build with your kernel tree. > > I never used FC or RedHat, so can't answer about it. > > > OK. Thanks. I made you suggested modifications to the code, and I > will recompile and try it out tonight when I get home. I also sent a > datasheet request to the SiS development team for the SiS7012 > datasheet. Probably a long shot, but you never know. It might pan > out. > > I also looked at a datasheet (Apr. 2002 Rev 1.1) for the CMI9738 and > the only digital output that I can see is the SDATA_OUT line which I > believe is a part of the AC-Link bus. Could this line also be tapped > to provide an spdif output? It's a serial line for the whole outputs. Usually slot 10/11 is used for SPDIF output in it. > If so, I noticed some code in intel8x0.c > that uses an undocumented module option: > > module_param(spdif_aclink, int, 0444); > MODULE_PARM_DESC(spdif_aclink, "S/PDIF over AC-link."); > > Looking through the code right now, this module option doesn't seem to > have any effect on SiS7012 devices. However, if some of the other > intel8x0 devices enable S/PDIF over the AC-link connection, is it > possible that the SiS7012 can do this also? It plays no role for SIS7012 but only for ICH4 or later. ICH4 or later chip has a dedicated DMA for SPDIF output, and it's found that some boards don't use this but just transmit through the normal DMA. SIS7012 may have similar thing but who knows :) Takashi _______________________________________________ Alsa-devel mailing list Alsa-devel@xxxxxxxxxxxxxxxx http://mailman.alsa-project.org/mailman/listinfo/alsa-devel
