USB: serial: ch341: add register and USB request definitions
Aidan Thornton authored
commit 6fde8d29

 upstream.

No functional changes, this just gives names to some registers and USB
requests based on Grigori Goronzy's work and WinChipTech's Linux driver
(which reassuringly agree), then uses them in place of magic numbers.
This also renames the misnamed BREAK2 register (actually UART config)
Signed-off-by: default avatarAidan Thornton <makosoft@gmail.com>
Reviewed-by: default avatarGrigori Goronzy <greg@chown.ath.cx>
Signed-off-by: default avatarJohan Hovold <johan@kernel.org>
[bwh: Backported to 3.2: adjust context]
Signed-off-by: default avatarBen Hutchings <ben@decadent.org.uk>
b4b2c4fb