From mboxrd@z Thu Jan 1 00:00:00 1970 From: Takashi Iwai Subject: Re: intel8x0 dual codec issue Date: Thu, 10 Feb 2005 18:27:08 +0100 Message-ID: References: <4208437B.3080207@request.com> Mime-Version: 1.0 (generated by SEMI 1.14.5 - "Awara-Onsen") Content-Type: multipart/mixed; boundary="Multipart_Thu_Feb_10_18:27:08_2005-1" In-Reply-To: <4208437B.3080207@request.com> Sender: alsa-devel-admin@lists.sourceforge.net Errors-To: alsa-devel-admin@lists.sourceforge.net List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: Ron Cococcia Cc: alsa-devel@lists.sourceforge.net List-Id: alsa-devel@alsa-project.org --Multipart_Thu_Feb_10_18:27:08_2005-1 Content-Type: text/plain; charset=US-ASCII At Mon, 07 Feb 2005 23:43:39 -0500, Ron Cococcia wrote: > > Hello, > > I'm having a little trouble with a dual codec setup that I am using. > The motherboard has an Intel 815 chip (82801BAICH2). The motherboard > has the primary (00) codec, which is an AD1885. A secondary (01) codec > has been added over a CNR connector. This one is a CS4299. The > secondary codec uses the timing values generated by the primary. > > I had been hearing some distortion in the audio. It was quite > noticeable. Using a wav file of sine waves that has different > frequencies (440, 880, 1760, 3520) at 44100Hz, I could see that there > was some jitter on a scope. As the frequencies went up, it got worse. > I then created another test file with the same frequencies, but sampled > at 48000Hz. Playback of that audio was extremely clean on the scope. > > Looking into it more, I noticed that the PCM front DAC (ac97#1-1) was > not adjusting itself to the appropriate frequency. The DAC on the > primary codec was switching between 44100Hz and 48000Hz when I played > the different samples. > > I'd like to have the secondary codec reflect the output rate that is > being sent to it. How might I get it to do this? Is it a bug (should > the codec front DAC on the secondary codec reflect the appropriate > frequency?), or how is it intended to work? I guess it's a bug. Could you try the attached patch? Takashi --Multipart_Thu_Feb_10_18:27:08_2005-1 Content-Type: text/plain; charset=US-ASCII Index: alsa-kernel/pci/ac97/ac97_pcm.c =================================================================== RCS file: /suse/tiwai/cvs/alsa/alsa-kernel/pci/ac97/ac97_pcm.c,v retrieving revision 1.19 diff -u -r1.19 ac97_pcm.c --- alsa-kernel/pci/ac97/ac97_pcm.c 27 Dec 2004 13:19:32 -0000 1.19 +++ alsa-kernel/pci/ac97/ac97_pcm.c 10 Feb 2005 17:19:45 -0000 @@ -602,8 +602,10 @@ snd_printk(KERN_ERR "invalid AC97 slot %i?\n", i); continue; } +#if 0 if (reg_ok & (1 << (reg - AC97_PCM_FRONT_DAC_RATE))) continue; +#endif //printk(KERN_DEBUG "setting ac97 reg 0x%x to rate %d\n", reg, rate); err = snd_ac97_set_rate(pcm->r[r].codec[cidx], reg, rate); if (err < 0) --Multipart_Thu_Feb_10_18:27:08_2005-1-- ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click