1 files changed, 89 insertions, 27 deletions

diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index eaeb9a02c7fe..57ca61b14670 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -61,7 +61,7 @@ static void uart_port_shutdown(struct tty_port *port);
 
 static int uart_dcd_enabled(struct uart_port *uport)
 {
-	return uport->status & UPSTAT_DCD_ENABLE;
+	return !!(uport->status & UPSTAT_DCD_ENABLE);
 }
 
 /*
@@ -436,7 +436,7 @@ uart_get_divisor(struct uart_port *port, unsigned int baud)
 
 EXPORT_SYMBOL(uart_get_divisor);
 
-/* FIXME: Consistent locking policy */
+/* Caller holds port mutex */
 static void uart_change_speed(struct tty_struct *tty, struct uart_state *state,
 					struct ktermios *old_termios)
 {
@@ -537,9 +537,10 @@ static int uart_write(struct tty_struct *tty,
 		count -= c;
 		ret += c;
 	}
+
+	__uart_start(tty);
 	spin_unlock_irqrestore(&port->lock, flags);
 
-	uart_start(tty);
 	return ret;
 }
 
@@ -618,7 +619,7 @@ static void uart_throttle(struct tty_struct *tty)
 {
 	struct uart_state *state = tty->driver_data;
 	struct uart_port *port = state->uart_port;
-	uint32_t mask = 0;
+	upf_t mask = 0;
 
 	if (I_IXOFF(tty))
 		mask |= UPF_SOFT_FLOW;
@@ -641,7 +642,7 @@ static void uart_unthrottle(struct tty_struct *tty)
 {
 	struct uart_state *state = tty->driver_data;
 	struct uart_port *port = state->uart_port;
-	uint32_t mask = 0;
+	upf_t mask = 0;
 
 	if (I_IXOFF(tty))
 		mask |= UPF_SOFT_FLOW;
@@ -1151,6 +1152,47 @@ static int uart_get_icount(struct tty_struct *tty,
 	return 0;
 }
 
+static int uart_get_rs485_config(struct uart_port *port,
+			 struct serial_rs485 __user *rs485)
+{
+	unsigned long flags;
+	struct serial_rs485 aux;
+
+	spin_lock_irqsave(&port->lock, flags);
+	aux = port->rs485;
+	spin_unlock_irqrestore(&port->lock, flags);
+
+	if (copy_to_user(rs485, &aux, sizeof(aux)))
+		return -EFAULT;
+
+	return 0;
+}
+
+static int uart_set_rs485_config(struct uart_port *port,
+			 struct serial_rs485 __user *rs485_user)
+{
+	struct serial_rs485 rs485;
+	int ret;
+	unsigned long flags;
+
+	if (!port->rs485_config)
+		return -ENOIOCTLCMD;
+
+	if (copy_from_user(&rs485, rs485_user, sizeof(*rs485_user)))
+		return -EFAULT;
+
+	spin_lock_irqsave(&port->lock, flags);
+	ret = port->rs485_config(port, &rs485);
+	spin_unlock_irqrestore(&port->lock, flags);
+	if (ret)
+		return ret;
+
+	if (copy_to_user(rs485_user, &port->rs485, sizeof(port->rs485)))
+		return -EFAULT;
+
+	return 0;
+}
+
 /*
  * Called via sys_ioctl.  We can use spin_lock_irq() here.
  */
@@ -1173,11 +1215,15 @@ uart_ioctl(struct tty_struct *tty, unsigned int cmd,
 		break;
 
 	case TIOCSSERIAL:
+		down_write(&tty->termios_rwsem);
 		ret = uart_set_info_user(tty, state, uarg);
+		up_write(&tty->termios_rwsem);
 		break;
 
 	case TIOCSERCONFIG:
+		down_write(&tty->termios_rwsem);
 		ret = uart_do_autoconfig(tty, state);
+		up_write(&tty->termios_rwsem);
 		break;
 
 	case TIOCSERGWILD: /* obsolete */
@@ -1217,11 +1263,19 @@ uart_ioctl(struct tty_struct *tty, unsigned int cmd,
 	 * All these rely on hardware being present and need to be
 	 * protected against the tty being hung up.
 	 */
+
 	switch (cmd) {
 	case TIOCSERGETLSR: /* Get line status register */
 		ret = uart_get_lsr_info(tty, state, uarg);
 		break;
 
+	case TIOCGRS485:
+		ret = uart_get_rs485_config(state->uart_port, uarg);
+		break;
+
+	case TIOCSRS485:
+		ret = uart_set_rs485_config(state->uart_port, uarg);
+		break;
 	default: {
 		struct uart_port *uport = state->uart_port;
 		if (uport->ops->ioctl)
@@ -1240,8 +1294,11 @@ static void uart_set_ldisc(struct tty_struct *tty)
 	struct uart_state *state = tty->driver_data;
 	struct uart_port *uport = state->uart_port;
 
-	if (uport->ops->set_ldisc)
-		uport->ops->set_ldisc(uport, tty->termios.c_line);
+	if (uport->ops->set_ldisc) {
+		mutex_lock(&state->port.mutex);
+		uport->ops->set_ldisc(uport, &tty->termios);
+		mutex_unlock(&state->port.mutex);
+	}
 }
 
 static void uart_set_termios(struct tty_struct *tty,
@@ -1278,7 +1335,9 @@ static void uart_set_termios(struct tty_struct *tty,
 		return;
 	}
 
+	mutex_lock(&state->port.mutex);
 	uart_change_speed(tty, state, old_termios);
+	mutex_unlock(&state->port.mutex);
 	/* reload cflag from termios; port driver may have overriden flags */
 	cflag = tty->termios.c_cflag;
 
@@ -1331,8 +1390,16 @@ static void uart_close(struct tty_struct *tty, struct file *filp)
 	struct uart_port *uport;
 	unsigned long flags;
 
-	if (!state)
+	if (!state) {
+		struct uart_driver *drv = tty->driver->driver_state;
+
+		state = drv->state + tty->index;
+		port = &state->port;
+		spin_lock_irq(&port->lock);
+		--port->count;
+		spin_unlock_irq(&port->lock);
 		return;
+	}
 
 	uport = state->uart_port;
 	port = &state->port;
@@ -1361,10 +1428,6 @@ static void uart_close(struct tty_struct *tty, struct file *filp)
 
 	mutex_lock(&port->mutex);
 	uart_shutdown(tty, state);
-	uart_flush_buffer(tty);
-
-	tty_ldisc_flush(tty);
-
 	tty_port_tty_set(port, NULL);
 	tty->closing = 0;
 	spin_lock_irqsave(&port->lock, flags);
@@ -1372,8 +1435,7 @@ static void uart_close(struct tty_struct *tty, struct file *filp)
 	if (port->blocked_open) {
 		spin_unlock_irqrestore(&port->lock, flags);
 		if (port->close_delay)
-			msleep_interruptible(
-					jiffies_to_msecs(port->close_delay));
+			msleep_interruptible(jiffies_to_msecs(port->close_delay));
 		spin_lock_irqsave(&port->lock, flags);
 	} else if (!uart_console(uport)) {
 		spin_unlock_irqrestore(&port->lock, flags);
@@ -1391,6 +1453,8 @@ static void uart_close(struct tty_struct *tty, struct file *filp)
 	wake_up_interruptible(&port->close_wait);
 
 	mutex_unlock(&port->mutex);
+
+	tty_ldisc_flush(tty);
 }
 
 static void uart_wait_until_sent(struct tty_struct *tty, int timeout)
@@ -1552,6 +1616,10 @@ static int uart_open(struct tty_struct *tty, struct file *filp)
 
 	pr_debug("uart_open(%d) called\n", line);
 
+	spin_lock_irq(&port->lock);
+	++port->count;
+	spin_unlock_irq(&port->lock);
+
 	/*
 	 * We take the semaphore here to guarantee that we won't be re-entered
 	 * while allocating the state structure, or while we request any IRQs
@@ -1564,17 +1632,11 @@ static int uart_open(struct tty_struct *tty, struct file *filp)
 		goto end;
 	}
 
-	port->count++;
 	if (!state->uart_port || state->uart_port->flags & UPF_DEAD) {
 		retval = -ENXIO;
-		goto err_dec_count;
+		goto err_unlock;
 	}
 
-	/*
-	 * Once we set tty->driver_data here, we are guaranteed that
-	 * uart_close() will decrement the driver module use count.
-	 * Any failures from here onwards should not touch the count.
-	 */
 	tty->driver_data = state;
 	state->uart_port->state = state;
 	state->port.low_latency =
@@ -1595,8 +1657,7 @@ static int uart_open(struct tty_struct *tty, struct file *filp)
 
 end:
 	return retval;
-err_dec_count:
-	port->count--;
+err_unlock:
 	mutex_unlock(&port->mutex);
 	goto end;
 }
@@ -2092,6 +2153,7 @@ uart_report_port(struct uart_driver *drv, struct uart_port *port)
 		break;
 	case UPIO_MEM:
 	case UPIO_MEM32:
+	case UPIO_MEM32BE:
 	case UPIO_AU:
 	case UPIO_TSI:
 		snprintf(address, sizeof(address),
@@ -2339,8 +2401,6 @@ int uart_register_driver(struct uart_driver *drv)
 
 		tty_port_init(port);
 		port->ops = &uart_port_ops;
-		port->close_delay     = HZ / 2;	/* .5 seconds */
-		port->closing_wait    = 30 * HZ;/* 30 seconds */
 	}
 
 	retval = tty_register_driver(normal);
@@ -2589,11 +2649,12 @@ int uart_add_one_port(struct uart_driver *drv, struct uart_port *uport)
 		goto out;
 	}
 
+	/* Link the port to the driver state table and vice versa */
 	state->uart_port = uport;
-	state->pm_state = UART_PM_STATE_UNDEFINED;
+	uport->state = state;
 
+	state->pm_state = UART_PM_STATE_UNDEFINED;
 	uport->cons = drv->cons;
-	uport->state = state;
 
 	/*
 	 * If this port is a console, then the spinlock is already
@@ -2736,6 +2797,7 @@ int uart_match_port(struct uart_port *port1, struct uart_port *port2)
 		       (port1->hub6   == port2->hub6);
 	case UPIO_MEM:
 	case UPIO_MEM32:
+	case UPIO_MEM32BE:
 	case UPIO_AU:
 	case UPIO_TSI:
 		return (port1->mapbase == port2->mapbase);