diff options
| author | Russell King <rmk@dyn-67.arm.linux.org.uk> | 2005-06-29 21:40:53 +0400 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2005-06-29 21:40:53 +0400 |
| commit | 0dd7a1aed7c34a39917c4faf75b4230c169e809b (patch) | |
| tree | 9c3eea7c817b19b50ece862af063c06ab7216c6d /drivers/serial | |
| parent | c5f4644e6c8ba21666128603e4e92544d3cd740d (diff) | |
| download | linux-0dd7a1aed7c34a39917c4faf75b4230c169e809b.tar.xz | |
[PATCH] Serial: Check status of CTS when using flow control
Fix bugme #4712: read the CTS status and set hw_stopped if CTS
is not active when opening the port and/or enabling CRTSCTS
Thanks to Stefan Wolff for spotting this problem.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'drivers/serial')
| -rw-r--r-- | drivers/serial/serial_core.c | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c index f5ce58d0514d..139863a787f3 100644 --- a/drivers/serial/serial_core.c +++ b/drivers/serial/serial_core.c @@ -182,6 +182,13 @@ static int uart_startup(struct uart_state *state, int init_hw) uart_set_mctrl(port, TIOCM_RTS | TIOCM_DTR); } + if (info->flags & UIF_CTS_FLOW) { + spin_lock_irq(&port->lock); + if (!(port->ops->get_mctrl(port) & TIOCM_CTS)) + info->tty->hw_stopped = 1; + spin_unlock_irq(&port->lock); + } + info->flags |= UIF_INITIALIZED; clear_bit(TTY_IO_ERROR, &info->tty->flags); @@ -1134,6 +1141,16 @@ static void uart_set_termios(struct tty_struct *tty, struct termios *old_termios spin_unlock_irqrestore(&state->port->lock, flags); } + /* Handle turning on CRTSCTS */ + if (!(old_termios->c_cflag & CRTSCTS) && (cflag & CRTSCTS)) { + spin_lock_irqsave(&state->port->lock, flags); + if (!(state->port->ops->get_mctrl(state->port) & TIOCM_CTS)) { + tty->hw_stopped = 1; + state->port->ops->stop_tx(state->port, 0); + } + spin_unlock_irqrestore(&state->port->lock, flags); + } + #if 0 /* * No need to wake up processes in open wait, since they |