On Fri, Mar 26, 2010 at 12:17:34PM -0300, Mauro Carvalho Chehab wrote: > David Härdeman wrote: > > On Thu, Mar 25, 2010 at 11:42:33AM -0300, Mauro Carvalho Chehab wrote: > >>> 2) add current_protocol support on other drivers; > >> Done. Patch were already merged upstream. > >> > >> The current_protocol attribute shows the protocol(s) that the device is accepting > >> and allows changing it to another protocol. > >> > >> In the case of the em28xx hardware, only one protocol can be active, since the decoder > >> is inside the hardware. > >> > >> On the raw IR decode implementation I've done at the saa7134, all raw pulse events are > >> sent to all registered decoders, so I'm thinking on using this sysfs node to allow > >> disabling the standard behavior of passing the IR codes to all decoders, routing it > >> to just one decoder. > >> > >> Another alternative would be to show current_protocol only for devices with hardware > >> decoder, and create one sysfs node for each decoder, allowing enabling/disabling each > >> decoder individually. > > > > You're eventually going to want to add ioctl's to set a lot of TX or RX > > parameters in one go (stuff like active receiver(s) and transmitter(s), > > carrier frequency, duty cycle, timeouts, filter levels and resolution - > > all of which would need to be set in one operation since some hardware > > will need to be reset after each parameter is changed). > > TX is a completely different history. It has nothing to do with input event > subsystem. So, another approach should be taken for it. I suggest (though I might not have been clear on that point) that irrcv devices create a char node...ir specifics are handled via that node (with read/write/ioctl...see the other mail I just send). > I haven't seen yet a hardware decoder with such parameters, but maybe I just > don't have enough specs here to adjust them. The entire idea is to have a common API for hardware decoders and decoders which provide raw pulse/space timings. That, to me, is one of the major points of having in-kernel IR decoders - being able to provide a consistent interface for both hardware decoders and pulse/space hardware. > Anyway, one simple way to avoid > resetting the hardware for every new parameter change would be to use a timer > for reset. This way, an userspace application or script that is touching on > several parameters would just send the complete RX init sequence and > after some dozens of milliseconds, the hardware will load the new parameters. And I do not think that sounds like a good interface. > > Then you'll end up with a few things being controlled via sysfs and some > > being controlled via ioctls. Maybe it's a good idea to have a bitmask of > > supported and enabled protocols in those ioctls instead? > > There's an interesting discussion about bitmasks x a list of enumerated values > as a way to represent a bitmask into a series of values on sysfs, > at http://lwn.net/Articles/378219/ (see "A critical look at sysfs attribute values" > article there). Not really relevant...that's just the minor detail of how a sysfs file might be represented. > That's said, I'm starting to think that the better is to have some differentiation > there between hardware and software decoders. IMO, software decoders are better > handled with an "enabled" attribute, per software decoder, inside each irrcv. I think we can create an interface which obscures the differences: Software decoders will export all in-kernel IR decoders in a bitmask in the "supported_protocols" sysfs file or ioctl struct member. Hardware decoders will export the hardware supported protocol(s) in the same file/member. In addition, a sysfs file or ioctl member for "enabled_protocols" will control either the enabled in-kernel IR decoders or hardware decoder(s). As should be quite obvious by now...I suggest ioctls (on a irrcv specific chardev) for controlling this :) -- David Härdeman -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
