[BRLTTY] BRLTTY in GRUB

[Vladimir 'φ-coder/phcoder' Serbinenko]

On 15.03.2012 14:51, Dave Mielke wrote:
> [quoted lines by Vladimir 'φ-coder/phcoder' Serbinenko on 2012/03/15 at 12:30 +0100]
>
>> I've managed to make baum driver (chosen because of qemu support) compile in
>> GRUB.
> I think it'd be best to find a way to get all of brltty built. The reason is
> that the individual drivers use a logial hgh level I/O layer which is
> implemented within the core. The core then would just require a set of
> grub-specific low level functions. This paradigm is how the core is able to
> support Linux, multiple other Unix flavours, Cygwin, Windows, and MS-DOS.
> Adding Grub as another platform shouldn't be that difficult if it's done in the
> same way.
I've pulled as much core as needed cutting at the lines where it was the 
easiest to implement a glue layer
>
>> It seems that the driver assumes that for USB devices it's assumed that after
>> isUsbDevice the device is equal to the USB serial.
> No. If brltty is given a USB device then it communicates with it directly using
> USB operations.
Then I don't understand following part:
static int
openUsbPort (const char *device) {
...
   if ((usbChannel = usbFindChannel(definitions, (void *)device))) {
     return 1;
   }

and usbFindChannel apparently searches by serial number.

>> Should I make isQualifiedDevice adjust device to strip usb/ ?
> You should not change any core function. Supporting a new platform, like Grub,
> shouldn't change more than absolutely necessary. In my opinion, that'd only be
> low level system interfacing.
I'll also need to #if-out some part, like anything using float/double 
since GRUB doesn't have those.
>> What are the functions usbReapResponse and usbSetAlternative are supposed to
>> do?
> They're part of the higher level USB interface. What'd need to be done is to
> implement a usb_grub.c which implements low level USB operations in the way
> that Grub needs them done.
I understand so much but what do they do exactly so I can implement them?
>   If Grub supports libusb, then that's already been
> done.
We don't implement libusb


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