path: root/drivers/usb/serial/ftdi_sio.c
diff options
authorDaniel Mack <daniel@caiaq.de>2010-06-03 13:55:02 +0200
committerGreg Kroah-Hartman <gregkh@suse.de>2010-06-04 13:16:19 -0700
commit6a1a82df91fa0eb1cc76069a9efe5714d087eccd (patch)
tree960e24f709aaf0101a831000a70d194bbc5bdf4c /drivers/usb/serial/ftdi_sio.c
parent1703a6d3c38944731ba23594843a704d828266f3 (diff)
USB: ftdi_sio: fix DTR/RTS line modes
Call set_mctrl() and clear_mctrl() according to the flow control mode selected. This makes serial communication for FT232 connected devices work when CRTSCTS is not set. This fixes a regression introduced by 4175f3e31 ("tty_port: If we are opened non blocking we still need to raise the carrier"). This patch calls the low-level driver's dtr_rts() function which consequently sets TIOCM_DTR | TIOCM_RTS. A later call to set_termios() without CRTSCTS in cflags, however, does not reset these bits, and so data is not actually sent out on the serial wire. Signed-off-by: Daniel Mack <daniel@caiaq.de> Cc: Johan Hovold <jhovold@gmail.com> Cc: Alan Cox <alan@linux.intel.com> Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/usb/serial/ftdi_sio.c')
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c
index 050211afc07..79dd1ae195e 100644
--- a/drivers/usb/serial/ftdi_sio.c
+++ b/drivers/usb/serial/ftdi_sio.c
@@ -2005,6 +2005,8 @@ static void ftdi_set_termios(struct tty_struct *tty,
"urb failed to set to rts/cts flow control\n");
+ /* raise DTR/RTS */
+ set_mctrl(port, TIOCM_DTR | TIOCM_RTS);
} else {
* Xon/Xoff code
@@ -2052,6 +2054,8 @@ static void ftdi_set_termios(struct tty_struct *tty,
+ /* lower DTR/RTS */
+ clear_mctrl(port, TIOCM_DTR | TIOCM_RTS);