Automatic Keyboard layout detection Was: two suggestion about ubuntu alternate cd

[Colin Watson]

On Mon, Oct 09, 2006 at 03:34:09PM +0200, David Balazic wrote:
> This is off topic, so please respond off list.

I don't think this is off-topic.

> Is there any effort towards "plug&play" keyboards ?
> That is keyboards, that can ID their layout to the host system.
> It would take a byte or two.

The USB HID specification allows a keyboard to report its layout via the
bCountryCode: see pages 32-33 of
<http://www.usb.org/developers/devclass_docs/HID1_11.pdf>. On the face
of it, this looks like what we'd want. However, Markus Kuhn describes
the problems with it here:

  http://lists.freedesktop.org/archives/xorg/2004-August/002472.html

My general feeling is that it's not sufficiently widely-implemented to
justify the effort of using it. I imagine that just picking the relevant
number off the USB bus would be easy enough, but mapping it to the
correct X keymap in a trustworthy way would be a long and drawn-out
process of finding users with keyboards that report each of the possible
layouts (keyboard layouts are notoriously hard to get right), and even
then we might well discover that some keyboards simply report the wrong
layout. The keypressing method of keyboard layout detection that we use
now seems to me to be a good compromise.

Cheers,

-- 
Colin Watson                                       [cjwatson at ubuntu.com]