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Date: Wed, 30 Nov 2011 15:35:00 +0900
From: Greg KH <gregkh@suse.de>
To: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Cc: NeilBrown <neilb@suse.de>, Linus Walleij <linus.walleij@linaro.org>,
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        Daniel WILLERUD <daniel.willerud@stericsson.com>
Subject: Re: [RFC PATCH 0/3] introduce: Multistate Switch Class
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On Mon, Nov 28, 2011 at 01:04:46AM -0800, Dmitry Torokhov wrote:
> On Mon, Nov 28, 2011 at 04:27:13PM +0900, Greg KH wrote:
> > On Mon, Nov 28, 2011 at 12:31:14PM +1100, NeilBrown wrote:
> > > 
> > >  My own thought is that this deserves a new device class which allows easy
> > >  hook-up of in-kernel signalling using notifications and which can be
> > >  exported as input devices in much the same way the 'gpio' devices can be
> > >  exported via gpio_keys.  The switch could also optionally be exported through
> > >  sysfs much like gpio can be exported through sysfs.
> > 
> > That might also work, but again, odds are the HID spec already defines
> > this type of "switch", so why recreate it as a different type of device?
> 
> HID does not map 1:1 on input. There are items in HID that are better
> served by other subsystems.

Ok fair enough.

So, how do you want this type of interface to look like, uevents only?

Or something like gpio?

Actually, why can't we just use gpio as-is here and just treat these
devices as "generic" i/o "pins"?

thanks,

greg k-h