[patch v2 0/6] staging: speakup: migrate synths to use TTY-based comms

[Okash Khawaja]

This patchset migrates all external synths from using raw serial i/o to
using tty-based comms. The synths not migrated are internal ones -
plugged directly into motherboard, communicating over ISA etc. It's
important to note that these patches access TTY from inside kernel.

Here is the summary of the patches in this set.

Patch 1: Exports tty_open_by_driver in order to allow the speakup to
access it.
Patch 2: Adds spk_ttyio.c, a container of TTY-based comms.
Patch 3: Migrates some synths which use relatively simple comms - output
only.
Patch 4: Adds more TTY-based functionality that wasn't already added in
patch 2.
Patch 5: Migrates remaining external synths based.
Patch 6: Contains these fixes: flushing TTY buffers and ensuring hardware
flow control.

Thanks,
Okash