On Fri, 2008-08-08 at 13:57 +0200, Hans Verkuil wrote: > On Friday 08 August 2008 13:33:35 Andy Walls wrote: > > On Fri, 2008-08-08 at 11:08 +0200, Hans Verkuil wrote: > > > Hi Mache, > > > > > > First try to use the 'bleeding edge' drivers > > > (http://www.ivtvdriver.org/index.php/Download#Bleeding_Edge_driver) > > >. > > > > > > If that gives you the same problem, then test whether calling > > > v4l2-ctl --set-audio-input=1 works for you or not and report back > > > the result. > > > > > > The problem with this issue is that 1) I can't reproduce it, and 2) > > > only a few people seem to get it. I thought I had it fixed, but > > > apparently it can still happen occasionally. > > > > Hans, > > > > My best guess, based on the information and cx25843 register dumps > > Kevin Blair provided in May, June and early July, is that the > > microcontroller is adjusting cx25843 register settings based on what > > its detecting from the tuner, even though line in what the user > > currently is using. > > > > There were a few changes to the cx25840 module in the past year and a > > half that may have inadvertently re-introduced the problem ( > > hg -v log -p cx25840-audio.c | less). Kevin found that rolling back > > kernel versions in his setup made the problem go away. > > > > I was going to try and reproduce the problem when I had some cx18 > > problems resolved (i.e. not for at least 2-3 weeks). I'm guessing a > > critical step to reproducing the problem would be to leave the > > antenna cable unhooked or to leave the tuner tuned to a channel that > > was weak or full of snow; thus causing the microcontroller to keep > > adjusting the cx28543 registers as it tried to process bogus SIF. > > Hi Andy, > > But how can this happen at all? With line-in selected the audio > microcontroller is stopped!
Oops, I missed that. In the mail Kevin Blair sent to the list on: Thu, 26 Jun 2008 10:41:58 -0300 (ADT) (09:41 EDT) Register 0x803 (I think) shows the microcontroller is stopped. > So it shouldn't touch registers at all. Although you may want to look at the register differences between the good and bad case that Kevin captured. Many of them are audio or AC97 interface related. Specifically registers: 0x88c, 0x88e, 0x898, 0x89a-0x89c, 0x89e-0x89f, 0x951, and 0x9ac Almost all of them are undocumented in the publicly available datasheet that I have. I doubt the AC97 0x9xx registers matter. > The > only thing I can think of that there is some race condition when > switching inputs where the microcontroller changes registers just > before it is turned off. Hmmm. Would cx28540-core.c:input_change() be a possible problem. input_change() since it resets the audio microcontroller and is called by cx28540-core.c:set_input() regardless of composite or tuner input? Regards, Andy > Regards, > > Hans > > > > > > > Regards, > > Andy > > > > > Regards, > > > > > > Hans > > > > > > On Friday 08 August 2008 06:41:51 Mache Creeger wrote: > > > > Any ideas? > > > > > > > > -- Mache > > > > > > > > At 08:02 PM 8/6/2008, Mache Creeger wrote: > > > > >I am using the latest MythTV release on the latest kernel > > > > > release of Fedora 9, with the nvidia kernel-specific drivers, > > > > > on an Asus P1-AH2 motherboard. I have a PVR-150 installed and > > > > > use the stereo and composite video RCA jacks for input from my > > > > > cable decoder box. I do not use the coax tuner as input. > > > > > > > > > >I get intermittent tininess in the audio when I record and I > > > > >experienced the exact same symptoms on an earlier system which > > > > > had a different PVR-150 in a VIA EPIA M10000 running Fedora 8 > > > > > and used the stereo and composite video RCA jacks. > > > > > > > > > >Based on that experience and other postings on the Internet, > > > > > there seems to be problem in the ivtv driver for the PVR-150 > > > > > that causes tininess in the audio when you record from the > > > > > stereo RCA jacks and not from the tuner > > > > > > > > > >I noticed that some folks run "/usr/local/bin/v4l2-ctl > > > > >--set-audio-input=1 -d /dev/video0" in a cron job that runs > > > > > every minute as a solution. > > > > > > > > > >Are there any other ways to address this problem? Has it been > > > > >registered as a bug and if so any idea if or when it could be > > > > > resolved? > > > > > > > > > >-- Mache Creeger > > > > > > _______________________________________________ > > > ivtv-users mailing list > > > [email protected] > > > http://ivtvdriver.org/mailman/listinfo/ivtv-users > > _______________________________________________ ivtv-users mailing list [email protected] http://ivtvdriver.org/mailman/listinfo/ivtv-users
