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Date: Sun, 7 Mar 2010 12:42:13 -0800
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Dima Zavin <dmitriyz@google.com>, Jonathan Cameron <jic23@cam.ac.uk>,
       LKML <linux-kernel@vger.kernel.org>, Zhang Rui <rui.zhang@intel.com>,
       Amit Kucheria <amit.kucheria@verdurent.com>,
       Jean Delvare <khali@linux-fr.org>
Subject: Re: [GIT PULL] Ambient Light Sensors subsystem
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On Wed, Mar 03, 2010 at 01:51:07PM -0800, Linus Torvalds wrote:
> 
> 
> On Wed, 3 Mar 2010, Dima Zavin wrote:
> > 
> > Actually, accelerometers fit into that model fine. They have some
> > variable number of absolute axes (3, 6, etc.).
> 
> In fact, they obviouslya also do end up being used exactly like joysticks 
> in real life, and joysticks are commonly starting to have accelerometers 
> in them (ie any modern game console controller).
> 
> So treating an accelerometer like a joystick - regardless of whether it 
> happens to be internal to the device or happens to be external in a 
> separate controller - is not all that far-fetched anyway.
> 

But the point is that not every accelerometer is a joystick. We have
hdaps and friends that have accelerometers inside but that is not their
main purpose (they do export a secondary joystick-like interface and
that is fine), and I am pretty sure that there are other users of
accelerometers in various systems.

I am retty sure that once we settle on the proper interface for such
sensors we should be able to write a bridge to input layer so they can
be easily used as [human] input devices in cases whether it is desired.

-- 
Dmitry