Re: [PATCH] Input: introduce device information ioctl

["Henrik Rydberg" <rydberg@euromail.se>]

On Fri, Dec 17, 2010 at 11:24:44AM -0800, Ping Cheng wrote:
> On Thu, Dec 16, 2010 at 12:30 PM, Henrik Rydberg <rydberg@euromail.se> wrote:
> > Today, userspace sets up an input device based on the data it emits.
> > This is not always enough; a tablet and a touchscreen may emit exactly
> > the same data, for instance, but the former should be set up with a
> > pointer whereas the latter does not need to. Recently, a new type of
> > touchpad has emerged where the buttons are under the pad, which
> > changes handling logic without changing the emitted data. This patch
> > introduces a new ioctl, EVIOCGPROP, which enables user access to a set
> > of device properties useful during setup. The properties are given as
> > a bitmap in the same fashion as the event types, and are also made
> > available via sysfs.
> >
> > Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
> 
> Reviewed-by: Ping Cheng <pingc@wacom.com>
> 
> I wonder if we need to mention this new ioctl somewhere under
> Documentation/input or not. INPUT_PROP_SEMI_MT could add useful
> information for multi-touch-protocol.txt. The others could play a role
> in Chase's new Documentation/input/evdev-codes.txt.

Thank you, Ping - I added an acked-by to the last version by mistake,
instead of a reviewed-by. Is that alright with you? And yes, I think the
properties need to be documented somewhere.

Henrik