Re: [PATCH 1/1] Input/Joystick Driver: add support AD7142 joystick driver (v2)

[Dmitry Torokhov <dmitry.torokhov@gmail.com>]

On Fri, Apr 25, 2008 at 06:09:52PM +0800, Bryan Wu wrote:
> On Sat, Apr 19, 2008 at 1:15 AM, Dmitry Torokhov
> <dmitry.torokhov@gmail.com> wrote:
> > Hi Bryan,
> >
> >
> >  On Thu, Mar 27, 2008 at 11:38:30AM -0700, Bryan Wu wrote:
> >  > +     input->keybit[BIT_WORD(BTN_BASE)] = BIT_MASK(BTN_BASE) |
> >  > +                                             BIT_MASK(BTN_BASE2) |
> >  > +                                             BIT_MASK(BTN_BASE3) |
> >  > +                                             BIT_MASK(BTN_BASE4);
> >  > +     input->keybit[BIT_WORD(KEY_UP)] |=  BIT_MASK(KEY_UP) |
> >  > +                                             BIT_MASK(KEY_DOWN) |
> >  > +                                             BIT_MASK(KEY_LEFT) |
> >  > +                                             BIT_MASK(KEY_RIGHT);
> >  > +
> >
> >  Why don't you use REL_X/REL_Y to report directional movement? Using
> >  buttons for that is pretty unusual.
> >
> 
> In our development board, it includes UP/DOWN/LEFT/RIGHT 4 buttons. So
> this driver matches this.
> Please found some information about the hardware as below:
> http://docs.blackfin.uclinux.org/doku.php?id=capacitance_touch_sensors&s[]=ad7142

What is the expected behaviur when a person touches one of these
buttons? Is it generatig a left/rigth mouse button clocks or moving a
pointer in some direction? Judging by the category of the devices you
are placing it in (joystick) it seems that latter is what you want,
therefore it should generate REL_X and REL_Y events. Otherwise it
should probably be called a button driver and live either in
drivers/input/keyboard or driver/input/misc. Do you agree?

Thanks.

-- 
Dmitry