On Monday 12 January 2009 06:19:47 Mauro Carvalho Chehab wrote: > On Sun, 11 Jan 2009 22:08:14 -0500 > > CityK <cityk@xxxxxxxxxx> wrote: > > Josh Borke wrote: > > > After upgrading to Fedora 10 I am no longer able to tune analog > > > or dvb channels using my KWorld ATSC 115. When I try to view a > > > channel with tvtime all I can see is static and when I try to > > > scandvb I keep getting tuning failed even though I know that > > > there are channels being broadcast on the channels scanned. I > > > have tried to find tips on the wiki of how to resolve my static > > > problem but I could not find any. I'm not sure where to look for > > > clues as to why it isn't working. > > > > > > I have a 1-to-4 splitter with 2 outputs going to the inputs of > > > the KWorld ATSC and another going to a TV so I know there is > > > signal on the cable. > > > > > > Any help would be really appreciated. > > > > Hello everyone, > > > > In addition to being a general broadcast message, I have cc'ed in > > a number of folks. > > > > This (broken analog TV on, at the very minimum, the KWorld 110 and > > 115 cards) is a known problem that has persisted for a long time. > > Far too long now. I last wrote about it here: > > http://marc.info/?l=linux-video&m=122809741331944&w=2. No response > > was generated from that. So I will try again and outline what I > > believe is the relevant history: > > > > - Mauro, you introduced a regression for these boards in changeset: > > 7753:67faa17a5bcb > > (http://linuxtv.org/hg/v4l-dvb/rev/67faa17a5bcb). Since that > > commit, analog TV has been broken for these cards. > > > > - Michael commented about this here: > > http://marc.info/?l=linux-video&m=121243712021921&w=2 > > > > - Mauro responded here: > > http://marc.info/?l=linux-video&m=121243995927725&w=2 > > > > - Several users have brought this up since then (both here on the > > m/l's and on internet forums) . > > > > - Michael spun a stopgap solution for this (found here > > > > :http://linuxtv.org/~mkrufky/fix-broken-atsc110-analog.patch > > > > <http://linuxtv.org/%7Emkrufky/fix-broken-atsc110-analog.patch> ). > > It still applies cleanly. Unfortunately, it is not a bonafide > > solution because: (a) upon each reboot of the system, the user is > > required to first "modprobe tuner -r" and then "modprobe tuner" > > before the analog tuning will initialize and function properly. > > (b) In addition, Michael's patch may affect/break other devices, so > > it can not be committed to the master repo. > > > > - Hans, I know you have done a lot of clean ups in regards to i2c, > > but do not know whether any of your work would have touched upon or > > have had any impact here. Nonetheless, I'd appreciate your input > > on the matter too if you are able to comment. > > > > I am hoping that this can be resolved to everyone's satisfaction. > > In my opinion, this should become a priority item, as this > > regression's life has spanned over 4 kernels. > > > > [For the sake of full disclosure, I am personally affected by the > > issue, but I note that I use Mike's patch each and everyday (thank > > you Mike!), and so, other then the minor inconvenience of having to > > do a modprobe dance with the tuner module, I am not impacted too > > much. Other users, however, are left in the dark. And, as I > > explained in my last message, those AVS users that I addressed this > > issue with seemed entirely hesitant about using the patch (maybe I > > scared them with a greivious warning ??). Anyway, as evidenced by > > Josh (OP for this message) and David (see his recent messages; > > e.g. > > http://marc.info/?l=linux-video&m=123066362106086&w=2), end users > > continue to encounter this problem. I am only surprised that we > > haven't heard more about this issue. As I noted earlier on, I > > believe that its impact is greater then just upon the KWorld 11x > > cards.] > > This issue doesn't have an easy fix. The big problem is that some > devices like Kworld ATSC 115 needs to send some i2c commands before > accessing the tuner. However, depending on the load order, the tuner > command can happen before the right time. This trouble is not > exclusive with saa7134. We have similar issues with cx88 (for > example, Kworld ATSC 120 suffers similar troubles). > > As you noticed, applying Michael patch will likely break other > drivers. > > The proper fix is a major saa7134 redesign, by using the newer i2c > methods. > > The new i2c interfaces allow you to register the i2c bus first, then > register each driver when you want to, and not relying on a code that > automatically registers all i2c video drivers found at a random > order. > > So, with the new i2c approach, we can warrant that we'll first open > the i2c gate before binding the tuner and/or the demodulator. > > Any other approach with the current way will break some other cards > or cause troubles on some situations, like having the driver compiled > monolithically with the kernel or if you have two boards on the > machine. > > The redesign of saa7134 requires lots of work. It requires to a full > understanding of Hans Verkuil approach used on ivtv. The ivtv driver > is different enough from the other drivers to allow an easy > conversion. Also, his approach changed recently with the introduction > of the v4l2 subdevices. Even the conversion of the cx18 driver (very > close to ivtv) to the newer approach doesn't seem to be that easy, as > noticed recently by Andy. > > IMO, the better would be if Hans could dedicate some time to convert > one of the drivers that have the more usual approach (saa7134, > em28xx, cx88, bttv) to the new approach. Then the same patch could be > easily converted to the other drivers. > > Hans, > > Could you help us with this? Yes, I can. I'll do saa7134 since I have an empress card anyway. It should be quite easy (the cx18 complication is not an issue here). Regards, Hans -- Hans Verkuil - video4linux developer - sponsored by TANDBERG -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
