serial: add port helpers

We can make this the same as the ones that will be needed by the tty_port
helper logic that we want to move to but still call them from the existing
code base.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c
index 424b1c7..2379045 100644 (file)
--- a/drivers/serial/serial_core.c
+++ b/drivers/serial/serial_core.c
@@ -1501,6 +1501,34 @@ static void uart_update_termios(struct tty_struct *tty,
        }
 }
 
+static int uart_carrier_raised(struct tty_port *port)
+{
+       struct uart_state *state = container_of(port, struct uart_state, port);
+       struct uart_port *uport = state->uart_port;
+       int mctrl;
+       mutex_lock(&port->mutex);
+       spin_lock_irq(&uport->lock);
+       uport->ops->enable_ms(uport);
+       mctrl = uport->ops->get_mctrl(uport);
+       spin_unlock_irq(&uport->lock);
+       mutex_unlock(&port->mutex);
+       if (mctrl & TIOCM_CAR)
+               return 1;
+       return 0;
+}
+
+static void uart_dtr_rts(struct tty_port *port, int onoff)
+{
+       struct uart_state *state = container_of(port, struct uart_state, port);
+       struct uart_port *uport = state->uart_port;
+       mutex_lock(&port->mutex);
+       if (onoff)
+               uart_set_mctrl(uport, TIOCM_DTR | TIOCM_RTS);
+       else
+               uart_clear_mctrl(uport, TIOCM_DTR | TIOCM_RTS);
+       mutex_unlock(&port->mutex);
+}
+
 /*
  * Block the open until the port is ready.  We must be called with
  * the per-port semaphore held.
@@ -1509,9 +1537,7 @@ static int
 uart_block_til_ready(struct file *filp, struct uart_state *state)
 {
        DECLARE_WAITQUEUE(wait, current);
-       struct uart_port *uport = state->uart_port;
        struct tty_port *port = &state->port;
-       unsigned int mctrl;
        unsigned long flags;
 
        spin_lock_irqsave(&port->lock, flags);
@@ -1555,23 +1581,14 @@ uart_block_til_ready(struct file *filp, struct uart_state *state)
                 * not set RTS here - we want to make sure we catch
                 * the data from the modem.
                 */
-               if (port->tty->termios->c_cflag & CBAUD) {
-                       mutex_lock(&port->mutex);
-                       uart_set_mctrl(uport, TIOCM_DTR);
-                       mutex_unlock(&port->mutex);
-               }
+               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.
                 */
-               mutex_lock(&port->mutex);
-               spin_lock_irq(&uport->lock);
-               uport->ops->enable_ms(uport);
-               mctrl = uport->ops->get_mctrl(uport);
-               spin_unlock_irq(&uport->lock);
-               mutex_unlock(&port->mutex);
-               if (mctrl & TIOCM_CAR)
+               if (tty_port_carrier_raised(port))
                        break;
 
                schedule();
@@ -2349,6 +2366,11 @@ static const struct tty_operations uart_ops = {
 #endif
 };
 
+static const struct tty_port_operations uart_port_ops = {
+       .carrier_raised = uart_carrier_raised,
+       .dtr_rts        = uart_dtr_rts,
+};
+
 /**
  *     uart_register_driver - register a driver with the uart core layer
  *     @drv: low level driver structure
@@ -2405,6 +2427,7 @@ int uart_register_driver(struct uart_driver *drv)
                struct tty_port *port = &state->port;
 
                tty_port_init(port);
+               port->ops = &uart_port_ops;
                port->close_delay     = 500;    /* .5 seconds */
                port->closing_wait    = 30000;  /* 30 seconds */
                tasklet_init(&state->tlet, uart_tasklet_action,