USB serial likes to use port->tty back pointers for the real work it does and
to do so without any actual locking. Unfortunately when you consider hangup
events, hangup/parallel reopen or even worse hangup followed by parallel close
events the tty->port and port->tty pointers are not guaranteed to be the same
as port->tty is the active tty while tty->port is the port the tty may or
may not still be attached to.
So rework the entire API to pass the tty struct. For console cases we need
to pass both for now. This shows up multiple drivers that immediately crash
with USB console some of which have been fixed in the process.
Longer term we need a proper tty as console abstraction
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Recent USB-serial devices using the WinChipHead CH340/CH341 chipset are
being shipped with a new vendor/product ID code pair, but an otherwise
identical device. (This is confirmed by looking at INF for the included
Windows driver.)
Patch is tested and working, both with new and old devices.
Signed-off-by: Michael F. Robbins <mrobbins@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The usb-serial core no longer checks these fields so remove them from
all of the individual drivers. They will be removed from the usb-serial
core in a patch later in the series.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The ch341 currently doesn't support most of the hardware setting. So to keep
the termios data right we propogate the old termios hardware values back then
encode the speed.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch makes four needlessly global functions static.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch implements a USB serial port driver for the Winchiphead
CH341 USB-RS232 Converter. This chip also implements an IEEE 1284
parallel port, I2C and SPI, but that is not supported by the driver.
Signed-off-by: Frank A Kingswood <frank@kingswood-consulting.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>