Commit 6a1a82df authored by Daniel Mack's avatar Daniel Mack Committed by Greg Kroah-Hartman

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 4175f3e3 ("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: default avatarDaniel 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: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 1703a6d3
...@@ -2005,6 +2005,8 @@ static void ftdi_set_termios(struct tty_struct *tty, ...@@ -2005,6 +2005,8 @@ static void ftdi_set_termios(struct tty_struct *tty,
"urb failed to set to rts/cts flow control\n"); "urb failed to set to rts/cts flow control\n");
} }
/* raise DTR/RTS */
set_mctrl(port, TIOCM_DTR | TIOCM_RTS);
} else { } else {
/* /*
* Xon/Xoff code * Xon/Xoff code
...@@ -2052,6 +2054,8 @@ static void ftdi_set_termios(struct tty_struct *tty, ...@@ -2052,6 +2054,8 @@ static void ftdi_set_termios(struct tty_struct *tty,
} }
} }
/* lower DTR/RTS */
clear_mctrl(port, TIOCM_DTR | TIOCM_RTS);
} }
return; return;
} }
......
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