Re: acpi/apm events as inputs: how to handle?

[Michael Tokarev <mjt@tls.msk.ru>]

Michael Tokarev wrote:
> Dmitry Torokhov wrote:
> []
>>> Well, you use event device in any case; as for finding right one - I guess
>>> you look at device capabilities and filter what you need ...
>>>
>>> {pts/0}%
>>> cat /sys/devices/LNXSYSTM:00/LNXPWRBN:00/input/input1/capabilities/key
>>> 100000 0 0 0
>> Exactly. Any driver working through evdev interface should examine
>> device's capabilities and decide whether it is interested in the
>> device or not.
> 
> Ok, got it.
> But I can't open the device multiple times, can I?
> Like, there's a daemon listening on volume up/down and other
> multimedia keys for example, and it can't listen to the same
> eventX as a daemon that's watching for power/sleep buttons, --
> instead, they should be combined into the same executable.
> Unless there's a way to multiplex the events...
> (Hmm, this becoming quite... ugly.  Oh well.)

Are the capabilities available over ioctl?  Because if not, it
really is a problem to find correct /sys file for a given /dev
node.  I'd rather not scan whole /sys to find the right device... ;)

> By the way, where are all the capabilities of input devices
> documented?

Looked at the code, but it's a bit... difficult to follow, so
to say.  What is in ../capabilities/keys, for example - is it
a bitmap of all keys the given event device can produce, based
on KEY_xxx constants from <linux/input.h> ?

/mjt