Merge tag 'tty-3.11-rc4' of git://git.kernel.org/pub/scm/linux/kernel…

…/git/gregkh/tty

Pull tty/serial driver fixes from Greg KH:
 "Here are 4 tiny tty and serial driver fixes for 3.11-rc4.

  Nothing big, a refcount leak, a module alias fix, and two fixes to the
  mxs-auart serial driver"

* tag 'tty-3.11-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  serial: arc_uart: Fix module alias
  tty_port: Fix refcounting leak in tty_port_tty_hangup()
  serial/mxs-auart: increase time to wait for transmitter to become idle
  serial/mxs-auart: fix race condition in interrupt handler

drivers/tty/serial/arc_uart.c

@@ -773,6 +773,6 @@ module_init(arc_serial_init);
 module_exit(arc_serial_exit);
 
 MODULE_LICENSE("GPL");
-MODULE_ALIAS("plat-arcfpga/uart");
+MODULE_ALIAS("platform:" DRIVER_NAME);
 MODULE_AUTHOR("Vineet Gupta");
 MODULE_DESCRIPTION("ARC(Synopsys) On-Chip(fpga) serial driver");

drivers/tty/serial/mxs-auart.c

@@ -678,11 +678,18 @@ static void mxs_auart_settermios(struct uart_port *u,
 
 static irqreturn_t mxs_auart_irq_handle(int irq, void *context)
 {
-	u32 istatus, istat;
+	u32 istat;
 	struct mxs_auart_port *s = context;
 	u32 stat = readl(s->port.membase + AUART_STAT);
 
-	istatus = istat = readl(s->port.membase + AUART_INTR);
+	istat = readl(s->port.membase + AUART_INTR);
+
+	/* ack irq */
+	writel(istat & (AUART_INTR_RTIS
+		| AUART_INTR_TXIS
+		| AUART_INTR_RXIS
+		| AUART_INTR_CTSMIS),
+			s->port.membase + AUART_INTR_CLR);
 
 	if (istat & AUART_INTR_CTSMIS) {
 		uart_handle_cts_change(&s->port, stat & AUART_STAT_CTS);
@@ -702,12 +709,6 @@ static irqreturn_t mxs_auart_irq_handle(int irq, void *context)
 		istat &= ~AUART_INTR_TXIS;
 	}
 
-	writel(istatus & (AUART_INTR_RTIS
-		| AUART_INTR_TXIS
-		| AUART_INTR_RXIS
-		| AUART_INTR_CTSMIS),
-			s->port.membase + AUART_INTR_CLR);
-
 	return IRQ_HANDLED;
 }
 
@@ -850,7 +851,7 @@ auart_console_write(struct console *co, const char *str, unsigned int count)
 	struct mxs_auart_port *s;
 	struct uart_port *port;
 	unsigned int old_ctrl0, old_ctrl2;
-	unsigned int to = 1000;
+	unsigned int to = 20000;
 
 	if (co->index >= MXS_AUART_PORTS || co->index < 0)
 		return;
@@ -871,18 +872,23 @@ auart_console_write(struct console *co, const char *str, unsigned int count)
 
 	uart_console_write(port, str, count, mxs_auart_console_putchar);
 
-	/*
-	 * Finally, wait for transmitter to become empty
-	 * and restore the TCR
-	 */
+	/* Finally, wait for transmitter to become empty ... */
 	while (readl(port->membase + AUART_STAT) & AUART_STAT_BUSY) {
+		udelay(1);
 		if (!to--)
 			break;
-		udelay(1);
 	}
 
-	writel(old_ctrl0, port->membase + AUART_CTRL0);
-	writel(old_ctrl2, port->membase + AUART_CTRL2);
+	/*
+	 * ... and restore the TCR if we waited long enough for the transmitter
+	 * to be idle. This might keep the transmitter enabled although it is
+	 * unused, but that is better than to disable it while it is still
+	 * transmitting.
+	 */
+	if (!(readl(port->membase + AUART_STAT) & AUART_STAT_BUSY)) {
+		writel(old_ctrl0, port->membase + AUART_CTRL0);
+		writel(old_ctrl2, port->membase + AUART_CTRL2);
+	}
 
 	clk_disable(s->clk);
 }

drivers/tty/tty_port.c

@@ -256,10 +256,9 @@ void tty_port_tty_hangup(struct tty_port *port, bool check_clocal)
 {
 	struct tty_struct *tty = tty_port_tty_get(port);
 
-	if (tty && (!check_clocal || !C_CLOCAL(tty))) {
+	if (tty && (!check_clocal || !C_CLOCAL(tty)))
 		tty_hangup(tty);
-		tty_kref_put(tty);
-	}
+	tty_kref_put(tty);
 }
 EXPORT_SYMBOL_GPL(tty_port_tty_hangup);