Matthias Schwarzott wrote: > On Montag, 27. Oktober 2008, Manu Abraham wrote: >> Hi Mathias, >> > Hi Manu! > >> Matthias Schwarzott wrote: >>> Hi Manu, hi Steven! >>> >>> It seems an update of dvb-core breaks tuning of cx24123. >>> After updating to latest v4l-dvb the nova-s plus card just did no longer >>> lock to any channel. So I bisected it, and found this commit: >>> >>> changeset: 9344:aa3a67b658e8 >>> parent: 9296:e2a8b9b9c294 >>> user: Manu Abraham <manu@xxxxxxxxxxx> >>> date: Tue Oct 14 23:34:07 2008 +0400 >>> summary: DVB-Core update >>> >>> http://linuxtv.org/hg/v4l-dvb/rev/aa3a67b658e8 >>> >>> It basically did update the dvb-kernel-thread and enhanced the code using >>> get_frontend_algo. >>> >>> The codepath when get_frontend_algo returns *_ALGO_HW stayed the same, >>> only one line got removed: params = &fepriv->parameter >>> >>> Just re-adding that line made my card working again. Either this was >>> lost, or the last two lines using "params" should also be converted to >>> directly use "&fepriv->parameters". >> True. In the port, the one line got missed out. Thanks for taking the >> time to look at it. >> >> BTW, i don't see any reason why cx24123 should be using HW_ALGO as it is >> a standard demodulator. When we have a dedicated microcontroller >> employed to do that check, we might like to use HW_ALGO, since it would >> simply handle it. Not in the case of standard demodulators. As an >> example i could say cinergyT2, dst etc would be candidates for HW_ALGO, >> where tuning is offloaded to a onboard microcontroller. >> > I dont have much insight in what these algo settings do. Only idea I have > about this is: cx24123 may not need software zigzag. Ok, should be fine, if that's the case. software zigzag is one thing, another is lock monitoring, ie: if LOCK fails, it should autotune by itself; similar to FE_CAN_RECOVER. Though it brings the disadvantge to the cx24123 driver that it will not try to reacquire a LOCK when LOCK fails for some unreason such as a signal dropuot etc, when using HW_ALGO: might cause not to regain a LOCK, would be a side effect, if it is incapable of doing a hardware based LOCK monitor. > If that gives a larger gain in lock-speed, then mt312 may also be a candidate > for ALGO_HW as it can lock to signals not exactly centered to the IF. > But I doubt, as that hw then should lock at the first try and not even trigger > zigzag steps. I don't think the MT312 does support either of the mentioned. Or does it ? Didn't take the time to look at the datasheet. Regards, Manu _______________________________________________ linux-dvb mailing list linux-dvb@xxxxxxxxxxx http://www.linuxtv.org/cgi-bin/mailman/listinfo/linux-dvb
