[MIPS] Preliminary patch for ip32 ttyS* device

[Giuseppe Sacco <giuseppe@eppesuigoccas.homedns.org>]

Hi all,
serial device on SGI O2 (mips64) is broken since 2.6.23. I proposed this
patch on October on the linux-mips lists, and I tried to get a better
patch. I would like to know if you think the change to
drivers/serial/serial_core.c are correct or not.

Basically the problem is that we can setup membase but we cannot setup
mapbase, so our 8250 uart seems to be unused by uart_match_port().

Any comments?

Thanks,
Giuseppe

---
diff --git a/arch/mips/sgi-ip32/ip32-platform.c
b/arch/mips/sgi-ip32/ip32-platform.c
index 7309e48..77febd6 100644
--- a/arch/mips/sgi-ip32/ip32-platform.c
+++ b/arch/mips/sgi-ip32/ip32-platform.c
@@ -42,7 +42,7 @@ static struct platform_device uart8250_device = {
 static int __init uart8250_init(void)
 {
        uart8250_data[0].membase = (void __iomem *) &mace->isa.serial1;
-       uart8250_data[1].membase = (void __iomem *) &mace->isa.serial1;
+       uart8250_data[1].membase = (void __iomem *) &mace->isa.serial2;
 
        return platform_device_register(&uart8250_device);
 }
diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c
index 3bb5d24..7caa877 100644
--- a/drivers/serial/serial_core.c
+++ b/drivers/serial/serial_core.c
@@ -2455,6 +2455,8 @@ int uart_match_port(struct uart_port *port1,
struct uart_port *port2)
        case UPIO_AU:
        case UPIO_TSI:
        case UPIO_DWAPB:
+               if (port1->mapbase==0 && port2->mapbase==0)
+                       return (port1->membase == port2->membase);
                return (port1->mapbase == port2->mapbase);
        }
        return 0;