[BRLTTY] BRLTTY in GRUB

[Vladimir 'φ-coder/phcoder' Serbinenko]

Hello, all. I've managed to make baum driver (chosen because of qemu 
support) compile in GRUB. The result is available at 
http://bzr.savannah.gnu.org/lh/grub/branches/brltty . However compiling 
is the only thing it does. I don't see how driver is supposed to be run 
and used. I see the functions:
static int
brl_construct (BrailleDisplay *brl, char **parameters, const char *device);
static void
brl_destruct (BrailleDisplay *brl);
static int
brl_writeWindow (BrailleDisplay *brl, const wchar_t *text);
static int
brl_writeStatus (BrailleDisplay *brl, const unsigned char *status);
However they all are static. Am I supposed to use some linker magic to 
pick them up?
brl_writeWindow ignores the text argument. Am I supposed to always use 
writeStatus ?
It seems that the driver assumes that for USB devices it's assumed that 
after isUsbDevice the device is equal to the USB serial. I thought of 
using usb/<some id> to avoid costly scanning just to find out if a USB 
device exists with given serial. Should I make isQualifiedDevice adjust 
device to strip usb/ ?
What are the functions usbReapResponse and usbSetAlternative are 
supposed to do?

-- 
Regards
Vladimir 'φ-coder/phcoder' Serbinenko