1 files changed, 21 insertions, 8 deletions

diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
index be95e55b228b..342e12fb1c25 100644
--- a/drivers/serial/8250.c
+++ b/drivers/serial/8250.c
@@ -12,8 +12,6 @@
  * the Free Software Foundation; either version 2 of the License, or
  * (at your option) any later version.
  *
- *  $Id: 8250.c,v 1.90 2002/07/28 10:03:27 rmk Exp $
- *
  * A note about mapbase / membase
  *
  *  mapbase is the physical address of the IO port.
@@ -1289,13 +1287,24 @@ static void serial8250_enable_ms(struct uart_port *port)
 static void
 receive_chars(struct uart_8250_port *up, unsigned int *status)
 {
-        struct tty_struct *tty = up->port.info->tty;
+        struct tty_struct *tty = up->port.info->port.tty;
         unsigned char ch, lsr = *status;
         int max_count = 256;
         char flag;
 
         do {
-                ch = serial_inp(up, UART_RX);
+                if (likely(lsr & UART_LSR_DR))
+                        ch = serial_inp(up, UART_RX);
+                else
+                        /*
+                         * Intel 82571 has a Serial Over Lan device that will
+                         * set UART_LSR_BI without setting UART_LSR_DR when
+                         * it receives a break. To avoid reading from the
+                         * receive buffer without UART_LSR_DR bit set, we
+                         * just force the read character to be 0
+                         */
+                        ch = 0;
+
                 flag = TTY_NORMAL;
                 up->port.icount.rx++;
 
@@ -1344,7 +1353,7 @@ receive_chars(struct uart_8250_port *up, unsigned int *status)
 
 ignore_char:
                 lsr = serial_inp(up, UART_LSR);
-        } while ((lsr & UART_LSR_DR) && (max_count-- > 0));
+        } while ((lsr & (UART_LSR_DR | UART_LSR_BI)) && (max_count-- > 0));
         spin_unlock(&up->port.lock);
         tty_flip_buffer_push(tty);
         spin_lock(&up->port.lock);
@@ -1427,7 +1436,7 @@ serial8250_handle_port(struct uart_8250_port *up)
 
         DEBUG_INTR("status = %x...", status);
 
-        if (status & UART_LSR_DR)
+        if (status & (UART_LSR_DR | UART_LSR_BI))
                 receive_chars(up, &status);
         check_modem_status(up);
         if (status & UART_LSR_THRE)
@@ -1877,6 +1886,8 @@ static int serial8250_startup(struct uart_port *port)
                  * allow register changes to become visible.
                  */
                 spin_lock_irqsave(&up->port.lock, flags);
+                if (up->port.flags & UPF_SHARE_IRQ)
+                        disable_irq_nosync(up->port.irq);
 
                 wait_for_xmitr(up, UART_LSR_THRE);
                 serial_out_sync(up, UART_IER, UART_IER_THRI);
@@ -1888,6 +1899,8 @@ static int serial8250_startup(struct uart_port *port)
                 iir = serial_in(up, UART_IIR);
                 serial_out(up, UART_IER, 0);
 
+                if (up->port.flags & UPF_SHARE_IRQ)
+                        enable_irq(up->port.irq);
                 spin_unlock_irqrestore(&up->port.lock, flags);
 
                 /*
@@ -2934,7 +2947,7 @@ static int __init serial8250_init(void)
         if (nr_uarts > UART_NR)
                 nr_uarts = UART_NR;
 
-        printk(KERN_INFO "Serial: 8250/16550 driver $Revision: 1.90 $ "
+        printk(KERN_INFO "Serial: 8250/16550 driver"
                 "%d ports, IRQ sharing %sabled\n", nr_uarts,
                 share_irqs ? "en" : "dis");
 
@@ -2995,7 +3008,7 @@ EXPORT_SYMBOL(serial8250_suspend_port);
 EXPORT_SYMBOL(serial8250_resume_port);
 
 MODULE_LICENSE("GPL");
-MODULE_DESCRIPTION("Generic 8250/16x50 serial driver $Revision: 1.90 $");
+MODULE_DESCRIPTION("Generic 8250/16x50 serial driver");
 
 module_param(share_irqs, uint, 0644);
 MODULE_PARM_DESC(share_irqs, "Share IRQs with other non-8250/16x50 devices"