Re: Input sysbsystema and hotplug

[Hannes Reinecke <hare@suse.de>]

Dmitry Torokhov wrote:
> Hi,
> 
> I am trying to convert input systsem to play nicely with sysfs and I am
> having trouble with hotplug agent. The old hotplug mechanism was using
> "input" as agent/subsystem name, unfortunately I can't simply use "input"
> class because when Greg added class_simple support to input handlers
> (evdev, mousedev, joydev, etc) he used that name. So currently stock
> kernel gets 2 types of hotplug events (from input core and from input
> handlers) with completely different arguments processed by the same
> input agent.
> 
> So I guess my question is: is there anyone who uses hotplug events
> for input interface devices (as in mouseX, eventX) as opposed to
> parent input devices (inputX). If not then I could rename Greg's class
> to "input_dev" and my new class to "input" and that will be compatible
> with older installations. 
> 
> Also, in the long run I would probably want to see something like this:
> 
> /sys/class/input---input0
> 		 |
> 		 |-input1
> 		 |
> 		 |-input2
> 		 |
> 		 |-mouse---mouse0
> 		 |	 |
> 		 |	 |-mouse1
> 		 |	 |
> 		 |	 --mice
> 		 |
> 		 |-event---event0
> 			 |
> 			 |-event1
> 			 |
> 			 |-event2
> 
> where inputX are class devices, mouse and event are subclasses of input
> class and mouseX and eventX are again class devices.
> 
> Objections, suggestions, etc? 
> 	 
Hmm. I don't like it very much as it mixes two different types of
devices (class devices and subclasses) into one directory.

I think it's cleaner to have two distinct class device types
(one for input_dev and one for input).

subclasses for the input class devices are a neat idea; but I fear the
hotplug event name will change for each subclass device ('input' will
become eg 'mouse'), so we again have to change all hotplug handlers.
And I don't see an easy solution for that ...

Cheers,

Hannes
-- 
Dr. Hannes Reinecke			hare@suse.de
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