Re: Fwd: [RFC] GRUB2 and braille support

[Mario Lang <mlang@delysid.org>]

"Vladimir 'φ-coder/phcoder' Serbinenko" <phcoder@gmail.com> writes:

> Now I'm working on braille support. I already coded 40x1 menu selector
> and menuentry editor. For 40x1 console I need to add scrolling first.
> it's in branches/a11y
> I also coded FTDI and PL3203 usbserial drivers. It's in branches/usb.

Some of our existing drivers implement well-known serial adaptors,
others need more low-level USB access which we provide through our
own internal USB stack impementation.

> Now we need the braille drivers to go in-between. I thought of importing
> Linux braille drivers since they seem to be under GPLv2+. I hope that I
> CC the right list for it. My plan is to have an import similar to what
> we have with libgcrypt: we copy the patches verbatim and try to emulate
> the environment similar to native one. If any preprocessing is needed we
> have 2 directories: one with files as they are imported and another with
> the files to compile. The second one is generated from the first one
> with python script at autogen phase. This way we avoid forking and can
> easily resync

That sounds like a nice plan.

> What do you think?

The drivers you want to import are at

svn://mielke.cc/main/brltty in subdirectory Drivers/Braille minus
a few like Skeleton, Libbraille and possibly BrlAPI.

As mentioned, these drivers use IO functions provides in
Programs/io_{serial,usb,bluetooth}.h which are implemented
for several platforms (Linux, BSDs, Windows and a few others).

The way the drivers work is currently a bit of a mixture.  These
days, most of the drivers enqueue driver-specific keycodes
which are mapped to commands in so-called keytables.
However, a few drivers still return commands, hardcoding
the mapping from keycodes to commands in the driver itself.

That said, there is probably quite some infrastructure code
which you will need to copy as well to get the drivers to work.

I guess another approach could be to treat GRUB2 as a platform
supported by brltty, but I really dont know anything about
GRUBs support for plugins or externally compiled code...

-- 
CYa,
  ⡍⠁⠗⠊⠕