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From: Greg Kroah-Hartman on 10 Aug 2010 18:10
From: Alan Cox <alan(a)linux.intel.com>

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(a)linux.intel.com>
Cc: Arnd Bergmann <arnd(a)arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)suse.de>
---
drivers/serial/serial_core.c | 51 ++++++++++++++++++++++++++++++-----------
1 files changed, 37 insertions(+), 14 deletions(-)

diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c
index 424b1c7..2379045 100644
--- 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,
--
1.7.2

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