1 files changed, 66 insertions, 69 deletions

diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index 29a7be47389a..df3a8c74358e 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -59,6 +59,11 @@ static void uart_change_pm(struct uart_state *state,
 
 static void uart_port_shutdown(struct tty_port *port);
 
+static int uart_dcd_enabled(struct uart_port *uport)
+{
+	return uport->status & UPSTAT_DCD_ENABLE;
+}
+
 /*
  * This routine is used by the interrupt handler to schedule processing in
  * the software interrupt portion of the driver.
@@ -90,7 +95,7 @@ static void __uart_start(struct tty_struct *tty)
 	struct uart_state *state = tty->driver_data;
 	struct uart_port *port = state->uart_port;
 
-	if (!tty->stopped && !tty->hw_stopped)
+	if (!uart_tx_stopped(port))
 		port->ops->start_tx(port);
 }
 
@@ -130,7 +135,6 @@ static int uart_port_startup(struct tty_struct *tty, struct uart_state *state,
 		int init_hw)
 {
 	struct uart_port *uport = state->uart_port;
-	struct tty_port *port = &state->port;
 	unsigned long page;
 	int retval = 0;
 
@@ -175,17 +179,14 @@ static int uart_port_startup(struct tty_struct *tty, struct uart_state *state,
 			if (tty->termios.c_cflag & CBAUD)
 				uart_set_mctrl(uport, TIOCM_RTS | TIOCM_DTR);
 		}
-		/*
-		 * if hw support flow control without software intervention,
-		 * then skip the below check
-		 */
-		if (tty_port_cts_enabled(port) &&
-		    !(uport->flags & UPF_HARD_FLOW)) {
-			spin_lock_irq(&uport->lock);
-			if (!(uport->ops->get_mctrl(uport) & TIOCM_CTS))
-				tty->hw_stopped = 1;
-			spin_unlock_irq(&uport->lock);
-		}
+
+		spin_lock_irq(&uport->lock);
+		if (uart_cts_enabled(uport) &&
+		    !(uport->ops->get_mctrl(uport) & TIOCM_CTS))
+			uport->hw_stopped = 1;
+		else
+			uport->hw_stopped = 0;
+		spin_unlock_irq(&uport->lock);
 	}
 
 	/*
@@ -439,7 +440,6 @@ EXPORT_SYMBOL(uart_get_divisor);
 static void uart_change_speed(struct tty_struct *tty, struct uart_state *state,
 					struct ktermios *old_termios)
 {
-	struct tty_port *port = &state->port;
 	struct uart_port *uport = state->uart_port;
 	struct ktermios *termios;
 
@@ -454,17 +454,19 @@ static void uart_change_speed(struct tty_struct *tty, struct uart_state *state,
 	uport->ops->set_termios(uport, termios, old_termios);
 
 	/*
-	 * Set flags based on termios cflag
+	 * Set modem status enables based on termios cflag
 	 */
+	spin_lock_irq(&uport->lock);
 	if (termios->c_cflag & CRTSCTS)
-		set_bit(ASYNCB_CTS_FLOW, &port->flags);
+		uport->status |= UPSTAT_CTS_ENABLE;
 	else
-		clear_bit(ASYNCB_CTS_FLOW, &port->flags);
+		uport->status &= ~UPSTAT_CTS_ENABLE;
 
 	if (termios->c_cflag & CLOCAL)
-		clear_bit(ASYNCB_CHECK_CD, &port->flags);
+		uport->status &= ~UPSTAT_DCD_ENABLE;
 	else
-		set_bit(ASYNCB_CHECK_CD, &port->flags);
+		uport->status |= UPSTAT_DCD_ENABLE;
+	spin_unlock_irq(&uport->lock);
 }
 
 static inline int __uart_put_char(struct uart_port *port,
@@ -604,12 +606,11 @@ static void uart_send_xchar(struct tty_struct *tty, char ch)
 	if (port->ops->send_xchar)
 		port->ops->send_xchar(port, ch);
 	else {
+		spin_lock_irqsave(&port->lock, flags);
 		port->x_char = ch;
-		if (ch) {
-			spin_lock_irqsave(&port->lock, flags);
+		if (ch)
 			port->ops->start_tx(port);
-			spin_unlock_irqrestore(&port->lock, flags);
-		}
+		spin_unlock_irqrestore(&port->lock, flags);
 	}
 }
 
@@ -652,12 +653,8 @@ static void uart_unthrottle(struct tty_struct *tty)
 		mask &= ~port->flags;
 	}
 
-	if (mask & UPF_SOFT_FLOW) {
-		if (port->x_char)
-			port->x_char = 0;
-		else
-			uart_send_xchar(tty, START_CHAR(tty));
-	}
+	if (mask & UPF_SOFT_FLOW)
+		uart_send_xchar(tty, START_CHAR(tty));
 
 	if (mask & UPF_HARD_FLOW)
 		uart_set_mctrl(port, TIOCM_RTS);
@@ -892,10 +889,11 @@ static int uart_set_info(struct tty_struct *tty, struct tty_port *port,
 			 */
 			if (uport->flags & UPF_SPD_MASK) {
 				char buf[64];
-				printk(KERN_NOTICE
-				       "%s sets custom speed on %s. This "
-				       "is deprecated.\n", current->comm,
-				       tty_name(port->tty, buf));
+
+				dev_notice(uport->dev,
+				       "%s sets custom speed on %s. This is deprecated.\n",
+				      current->comm,
+				      tty_name(port->tty, buf));
 			}
 			uart_change_speed(tty, state, NULL);
 		}
@@ -952,7 +950,7 @@ static int uart_get_lsr_info(struct tty_struct *tty,
 	 */
 	if (uport->x_char ||
 	    ((uart_circ_chars_pending(&state->xmit) > 0) &&
-	     !tty->stopped && !tty->hw_stopped))
+	     !uart_tx_stopped(uport)))
 		result &= ~TIOCSER_TEMT;
 
 	return put_user(result, value);
@@ -1251,7 +1249,6 @@ static void uart_set_termios(struct tty_struct *tty,
 {
 	struct uart_state *state = tty->driver_data;
 	struct uart_port *uport = state->uart_port;
-	unsigned long flags;
 	unsigned int cflag = tty->termios.c_cflag;
 	unsigned int iflag_mask = IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK;
 	bool sw_changed = false;
@@ -1291,34 +1288,33 @@ static void uart_set_termios(struct tty_struct *tty,
 	/* Handle transition away from B0 status */
 	else if (!(old_termios->c_cflag & CBAUD) && (cflag & CBAUD)) {
 		unsigned int mask = TIOCM_DTR;
-		if (!(cflag & CRTSCTS) ||
-		    !test_bit(TTY_THROTTLED, &tty->flags))
+		if (!(cflag & CRTSCTS) || !test_bit(TTY_THROTTLED, &tty->flags))
 			mask |= TIOCM_RTS;
 		uart_set_mctrl(uport, mask);
 	}
 
 	/*
 	 * If the port is doing h/w assisted flow control, do nothing.
-	 * We assume that tty->hw_stopped has never been set.
+	 * We assume that port->hw_stopped has never been set.
 	 */
 	if (uport->flags & UPF_HARD_FLOW)
 		return;
 
 	/* Handle turning off CRTSCTS */
 	if ((old_termios->c_cflag & CRTSCTS) && !(cflag & CRTSCTS)) {
-		spin_lock_irqsave(&uport->lock, flags);
-		tty->hw_stopped = 0;
+		spin_lock_irq(&uport->lock);
+		uport->hw_stopped = 0;
 		__uart_start(tty);
-		spin_unlock_irqrestore(&uport->lock, flags);
+		spin_unlock_irq(&uport->lock);
 	}
 	/* Handle turning on CRTSCTS */
 	else if (!(old_termios->c_cflag & CRTSCTS) && (cflag & CRTSCTS)) {
-		spin_lock_irqsave(&uport->lock, flags);
+		spin_lock_irq(&uport->lock);
 		if (!(uport->ops->get_mctrl(uport) & TIOCM_CTS)) {
-			tty->hw_stopped = 1;
+			uport->hw_stopped = 1;
 			uport->ops->stop_tx(uport);
 		}
-		spin_unlock_irqrestore(&uport->lock, flags);
+		spin_unlock_irq(&uport->lock);
 	}
 }
 
@@ -1975,12 +1971,9 @@ int uart_suspend_port(struct uart_driver *drv, struct uart_port *uport)
 		for (tries = 3; !ops->tx_empty(uport) && tries; tries--)
 			msleep(10);
 		if (!tries)
-			printk(KERN_ERR "%s%s%s%d: Unable to drain "
-					"transmitter\n",
-			       uport->dev ? dev_name(uport->dev) : "",
-			       uport->dev ? ": " : "",
-			       drv->dev_name,
-			       drv->tty_driver->name_base + uport->line);
+			dev_err(uport->dev, "%s%d: Unable to drain transmitter\n",
+				drv->dev_name,
+				drv->tty_driver->name_base + uport->line);
 
 		if (console_suspend_enabled || !uart_console(uport))
 			ops->shutdown(uport);
@@ -2109,9 +2102,7 @@ uart_report_port(struct uart_driver *drv, struct uart_port *port)
 		break;
 	}
 
-	printk(KERN_INFO "%s%s%s%d at %s (irq = %d, base_baud = %d) is a %s\n",
-	       port->dev ? dev_name(port->dev) : "",
-	       port->dev ? ": " : "",
+	dev_info(port->dev, "%s%d at %s (irq = %d, base_baud = %d) is a %s\n",
 	       drv->dev_name,
 	       drv->tty_driver->name_base + port->line,
 	       address, port->irq, port->uartclk / 16, uart_type(port));
@@ -2640,7 +2631,7 @@ int uart_add_one_port(struct uart_driver *drv, struct uart_port *uport)
 	if (likely(!IS_ERR(tty_dev))) {
 		device_set_wakeup_capable(tty_dev, 1);
 	} else {
-		printk(KERN_ERR "Cannot register tty device on line %d\n",
+		dev_err(uport->dev, "Cannot register tty device on line %d\n",
 		       uport->line);
 	}
 
@@ -2675,7 +2666,7 @@ int uart_remove_one_port(struct uart_driver *drv, struct uart_port *uport)
 	BUG_ON(in_interrupt());
 
 	if (state->uart_port != uport)
-		printk(KERN_ALERT "Removing wrong port: %p != %p\n",
+		dev_alert(uport->dev, "Removing wrong port: %p != %p\n",
 			state->uart_port, uport);
 
 	mutex_lock(&port_mutex);
@@ -2757,22 +2748,29 @@ EXPORT_SYMBOL(uart_match_port);
  *	uart_handle_dcd_change - handle a change of carrier detect state
  *	@uport: uart_port structure for the open port
  *	@status: new carrier detect status, nonzero if active
+ *
+ *	Caller must hold uport->lock
  */
 void uart_handle_dcd_change(struct uart_port *uport, unsigned int status)
 {
 	struct tty_port *port = &uport->state->port;
 	struct tty_struct *tty = port->tty;
-	struct tty_ldisc *ld = tty ? tty_ldisc_ref(tty) : NULL;
+	struct tty_ldisc *ld;
 
-	if (ld) {
-		if (ld->ops->dcd_change)
-			ld->ops->dcd_change(tty, status);
-		tty_ldisc_deref(ld);
+	lockdep_assert_held_once(&uport->lock);
+
+	if (tty) {
+		ld = tty_ldisc_ref(tty);
+		if (ld) {
+			if (ld->ops->dcd_change)
+				ld->ops->dcd_change(tty, status);
+			tty_ldisc_deref(ld);
+		}
 	}
 
 	uport->icount.dcd++;
 
-	if (port->flags & ASYNC_CHECK_CD) {
+	if (uart_dcd_enabled(uport)) {
 		if (status)
 			wake_up_interruptible(&port->open_wait);
 		else if (tty)
@@ -2785,26 +2783,25 @@ EXPORT_SYMBOL_GPL(uart_handle_dcd_change);
  *	uart_handle_cts_change - handle a change of clear-to-send state
  *	@uport: uart_port structure for the open port
  *	@status: new clear to send status, nonzero if active
+ *
+ *	Caller must hold uport->lock
  */
 void uart_handle_cts_change(struct uart_port *uport, unsigned int status)
 {
-	struct tty_port *port = &uport->state->port;
-	struct tty_struct *tty = port->tty;
+	lockdep_assert_held_once(&uport->lock);
 
 	uport->icount.cts++;
 
-	/* skip below code if the hw flow control is supported */
-	if (tty_port_cts_enabled(port) &&
-	    !(uport->flags & UPF_HARD_FLOW)) {
-		if (tty->hw_stopped) {
+	if (uart_cts_enabled(uport)) {
+		if (uport->hw_stopped) {
 			if (status) {
-				tty->hw_stopped = 0;
+				uport->hw_stopped = 0;
 				uport->ops->start_tx(uport);
 				uart_write_wakeup(uport);
 			}
 		} else {
 			if (!status) {
-				tty->hw_stopped = 1;
+				uport->hw_stopped = 1;
 				uport->ops->stop_tx(uport);
 			}
 		}