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serial: Use block_til_ready helper 

Our code now rather closely resembles the helper, so switch to it.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Alan Cox 2010-06-01 22:53:00 +02:00 committed by Greg Kroah-Hartman
parent 24fcc7c8cd
commit 74c2107759
1 changed files with 1 additions and 86 deletions
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87
drivers/serial/serial_core.c
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@ -1526,91 +1526,6 @@ static void uart_dtr_rts(struct tty_port *port, int onoff)
uart_clear_mctrl(uport, TIOCM_DTR | TIOCM_RTS);
}
/*
* Block the open until the port is ready. We must be called with
* the per-port semaphore held.
*/
static int
uart_block_til_ready(struct file *filp, struct uart_state *state)
{
DECLARE_WAITQUEUE(wait, current);
struct tty_port *port = &state->port;
unsigned long flags;
spin_lock_irqsave(&port->lock, flags);
if (!tty_hung_up_p(filp))
port->count--;
port->blocked_open++;
spin_unlock_irqrestore(&port->lock, flags);
add_wait_queue(&port->open_wait, &wait);
while (1) {
set_current_state(TASK_INTERRUPTIBLE);
/*
* If we have been hung up, tell userspace/restart open.
*/
if (tty_hung_up_p(filp) || port->tty == NULL)
break;
/*
* If the port has been closed, tell userspace/restart open.
*/
if (!(port->flags & ASYNC_INITIALIZED))
break;
/*
* If non-blocking mode is set, or CLOCAL mode is set,
* we don't want to wait for the modem status lines to
* indicate that the port is ready.
*
* Also, if the port is not enabled/configured, we want
* to allow the open to succeed here. Note that we will
* have set TTY_IO_ERROR for a non-existant port.
*/
if ((filp->f_flags & O_NONBLOCK) ||
(port->tty->termios->c_cflag & CLOCAL) ||
(port->tty->flags & (1 << TTY_IO_ERROR)))
break;
/*
* Set DTR to allow modem to know we're waiting. Do
* not set RTS here - we want to make sure we catch
* the data from the modem.
*/
if (port->tty->termios->c_cflag & CBAUD)
tty_port_raise_dtr_rts(port);
/*
* and wait for the carrier to indicate that the
* modem is ready for us.
*/
if (tty_port_carrier_raised(port))
break;
schedule();
if (signal_pending(current))
break;
}
set_current_state(TASK_RUNNING);
remove_wait_queue(&port->open_wait, &wait);
spin_lock_irqsave(&port->lock, flags);
if (!tty_hung_up_p(filp))
port->count++;
port->blocked_open--;
spin_unlock_irqrestore(&port->lock, flags);
if (signal_pending(current))
return -ERESTARTSYS;
if (!port->tty || tty_hung_up_p(filp))
return -EAGAIN;
return 0;
}
static struct uart_state *uart_get(struct uart_driver *drv, int line)
{
struct uart_state *state;
@ -1719,7 +1634,7 @@ static int uart_open(struct tty_struct *tty, struct file *filp)
*/
mutex_unlock(&port->mutex);
if (retval == 0)
retval = uart_block_til_ready(filp, state);
retval = tty_port_block_til_ready(port, tty, filp);
/*
* If this is the first open to succeed, adjust things to suit.