On Wed, 2010-07-28 at 17:24 +0300, Maxim Levitsky wrote: > On Wed, 2010-07-28 at 10:13 -0300, Mauro Carvalho Chehab wrote: > > Em 28-07-2010 07:40, Jon Smirl escreveu: > > > On Wed, Jul 28, 2010 at 2:30 AM, Maxim Levitsky <maximlevit...@gmail.com> > > > wrote: > > >> On Tue, 2010-07-27 at 22:33 -0400, Jarod Wilson wrote: > > >>> On Tue, Jul 27, 2010 at 9:29 PM, Jon Smirl <jonsm...@gmail.com> wrote: > > > > >> No its not, its just extended NEC. > > > > > > http://www.sbprojects.com/knowledge/ir/nec.htm > > > Says the last two bytes should be the complement of each other. > > > > > > So for extended NEC it would need to be: > > > 1100 0010 1010 0101 instead of 1100 0010 1010 0100 > > > The last bit is wrong. > > > > > > From the debug output it is decoding as NEC, but then it fails a > > > consistency check. Maybe we need to add a new protocol that lets NEC > > > commands through even if they fail the error checks. > > > > Assuming that Maxim's IR receiver is not causing some bad decode at the > > NEC code, it seems simpler to add a parameter at sysfs to relax the NEC > > detection. We should add some way, at the userspace table for those RC's > > that uses a NEC-like code. > > > > There's another alternative: currently, the NEC decoder produces a 16 bits > > code for NEC and a 24 bits for NEC-extended code. The decoder may return a > > 32 bits code when none of the checksum's match the NEC or NEC-extended > > standard. > > > > Such 32 bits code won't match a keycode on a 16-bits or 24-bits table, so > > there's no risk of generating a wrong keycode, if the wrong consistent check > > is due to a reception error. > > > > Btw, we still need to port rc core to use the new tables ioctl's, as > > cleaning > > all keycodes on a 32 bits table would take forever with the current input > > events ioctls. > > > > > It may also be > > > that the NEC machine rejected it because the timing was so far off > > > that it concluded that it couldn't be a NEC messages. The log didn't > > > include the exact reason it got rejected. Add some printks at the end > > > of the NEC machine to determine the exact reason for rejection. > > > > The better is to discard the possibility of a timing issue before changing > > the decoder to accept NEC-like codes without consistency checks. > > > > > The current state machines enforce protocol compliance so there are > > > probably a lot of older remotes that won't decode right. We can use > > > some help in adjusting the state machines to let out of spec codes > > > through. > > > > Yes, but we should take some care to avoid having another protocol decoder > > to > > interpret badly a different protocol. So, I think that the decoders may have > > some sysfs nodes to tweak the decoders to accept those older remotes. > > > > We'll need a consistent way to add some logic at the remotes keycodes used > > by > > ir-keycode, in order to allow it to tweak the decoder when a keycode table > > for > > such remote is loaded into the driver. > > > > > User space lirc is much older. Bugs like this have been worked out of > > > it. It will take some time to get the kernel implementation up to the > > > same level. > > > > True. > > > I more or less got to the bottom of this. > > > It turns out that ENE reciever has a non linear measurement error. > That is the longer sample is, the larger error it contains. > Substracting around 4% from the samples makes the output look much more > standard compliant. > > You are right that my remote has JVC protocol. (at least I am sure now > it hasn't NEC, because repeat looks differently). > > My remote now actually partially works with JVC decoder, it decodes > every other keypress. > > Still, no repeat is supported. > > However, all recievers (and transmitters) aren't perfect. > Thats why I prefer lirc, because it makes no assumptions about protocol, > so it can be 'trained' to work with any remote, and under very large > range of error tolerances. > > Best regards, > Maxim Levitsky >
I think I found the reason behind some of incorrect behavior. I see that in-kernel decoding is unhappy about the way I process gaps. I do exactly the same I did in lirc driver. At the end of keypress, the driver receives series of spaces from hardware. I accumulate 'em until patience^Wtimeout runs out. Then I put hardware in 'idle' mode, and remember current time. As soon as I get new pulse, I send a sum of accumulated same and time difference to user. Therefore every keypress ends with a pulse, and starts with space. But in-kernel decoding isn't happy about it, it seems.. at least NEC decoder... How you think to solve that? Fix in-kernel decoders maybe? Best regards, Maxim Levitsky -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
