Re: [RFC] What are the goals for the architecture of an in-kernel IR system?

Dmitry Torokhov
2009-12-04T22:07:10Z

On Fri, Dec 04, 2009 at 10:46:00PM +0100, Christoph Bartelmus wrote:
> Hi Mauro,
>
> on 04 Dec 09 at 12:33, Mauro Carvalho Chehab wrote:
> > Christoph Bartelmus wrote:
> >>>> Consider passing the decoded data through lirc_dev.
> [...]
> >> Consider cases like this:
> >> http://lirc.sourceforge.net/remotes/lg/6711A20015N
> >>
> >> This is an air-conditioner remote.
> >> The entries that you see in this config file are not really separate
> >> buttons. Instead the remote just sends the current settings for e.g.
> >> temperature encoded in the protocol when you press some up/down key. You
> >> really don't want to map all possible temperature settings to KEY_*
> >> events. For such cases it would be nice to have access at the raw scan
> >> codes from user space to do interpretation of the data.
> >> The default would still be to pass the data to the input layer, but it
> >> won't hurt to have the possibility to access the raw data somehow.
>
> > Interesting. IMHO, the better would be to add an evdev ioctl to return the
> > scancode for such cases, instead of returning the keycode.
>
> That means you would have to set up a pseudo keymap, so that you can get
> the key event which you could than react on with a ioctl. Or are you
> generating KEY_UNKNOWN for every scancode that is not mapped?
> What if different scan codes are mapped to the same key event? How do you
> retrieve the scan code for the key event?
> I don't think it can work this way.
>

EV_MSC/MSC_SCAN.

--
Dmitry