OSDN Git Service

USB: serial: f81534: add H/W disable port support
authorJi-Ze Hong (Peter Hong) <hpeter@gmail.com>
Thu, 11 Jan 2018 06:47:19 +0000 (14:47 +0800)
committerJohan Hovold <johan@kernel.org>
Thu, 11 Jan 2018 10:00:25 +0000 (11:00 +0100)
commitbb543ca287f5b14a61533f959e3f62ae58890311
tree016d618f1cec236484443c41e73a71cd8c68a244
parentf047d35782553ab862003a58b0fcf7e1b542e4f9
USB: serial: f81534: add H/W disable port support

The F81532/534 can be disable port by manufacturer with
following H/W design.
    1: Connect DCD/DSR/CTS/RI pin to ground.
    2: Connect RX pin to ground.

In driver, we'll implements some detect method likes following:
    1: Read MSR.
    2: Turn MCR LOOP bit on, off and read LSR after delay with 60ms.
       It'll contain BREAK status in LSR.

Signed-off-by: Ji-Ze Hong (Peter Hong) <hpeter+linux_kernel@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
drivers/usb/serial/f81534.c