Re: [gdm-list] Pairing bluetooth input devices before logging in?

[Mourad De Clerck <mourad aquazul com>]

Hi Bastien,

On 09/08/07 18:07, Bastien Nocera wrote:
> On Wed, 2007-08-08 at 11:13 -0400, William Jon McCann wrote:
> > On 8/7/07, Mourad De Clerck <mourad aquazul com> wrote:
> > > In light of the gdm rework that has been going on, I was wondering if
> > > and how the new gdm is going to handle bluetooth input devices.
> > That is a good point.  And may be yet another reason to make our GDM
> > greeters more session-like.
>
> I guess the problem is mostly for desktop PCs with builtin Bluetooth, or
> Bluetooth "proxy dongles" specific to the hardware used.
<snip>

Well, I'm assuming that the distro's init scripts will always set the 
dongles in HCI mode, and not leave them in HID mode. The only thing 
hid2hci can reliably do, is go from hid -> hci. Querying the mode 
doesn't work, and going hci -> hid often doesn't work either (Logitech).

> If you're thinking about a different use case/different hardware, let me
> know, but be aware that el-cheapo Taiwanese Bluetooth adapter and an
> unrelated Bluetooth keyboard will not work out of the box, and will
> never do (they don't know about each other, and there's no other way
> than pairing them).

That's pretty much the use case I've been seeing. To illustrate, these 
are the problems I've had with a Logitech diNovo keyboard:

- once the logitech dongle was in HCI mode, it would not go back to HID 
mode on reboot -> result is that I couldn't use the keyboard in 
BIOS/GRUB, and when dual-booting in windows the bluetooth stack there 
would not be able to "activate" the dongle (I'd have cut power 
completely so dongle is in HID mode first). This problem can't really be 
solved by bluez or gdm at all, since it's just caused by a lack of 
specs, and a silly windows stack.

- These days, I just use an el-cheapo bluetooth dongle (the logitech one 
died), so no hid2hci issues anymore. However, if I dual-boot, and pair 
the keyboard in windows (or MacOSX , haven't tried yet), then we lost 
the pairing in Linux and on reboot I have to plug in a USB keyboard to 
login and pair.

- Whenever I use my keyboard with other computers (laptop, 770, 
whatever), the same thing happens of course: as soon as I boot I have to 
go looking for an USB keyboard.

> In this use case, it would be nice to be able to type a password using a
> virtual keyboard, if the mouse is wired/working for example.

I'd like to suggest something slightly simpler even: just show all 
wireless (discoverable) HID devices somewhere in the GDM login screen, 
and when you click on one it generates and displays a random pin to 
initiate the pairing. Type it in and you're set.
If you've got no working input device (wired or wireless) at all, it 
automatically attempts to pair the discoverable mice first.

(I don't believe any state needs to be carried over between GDM and the 
user session, since it's all kept in the bluez stack, right?)

How does that sound?


-- Mourad