[patch 2/2] staging: sb105x: clean up interface type test

[Dan Carpenter <dan.carpenter@oracle.com>]

IIR_RS232 is zero so "if (IIR_RS232 = (b_ret & IIR_RS232))" is always
true so RS232 was always chosen by default.  The test should be
"if (0 = (b_ret & 0x30)) { ".  The other tests should also be in that
format.

My patch doesn't change how the code works.  I've left the RS232 as the
default and cleaned up the other checks.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

diff --git a/drivers/staging/sb105x/sb_mp_register.h b/drivers/staging/sb105x/sb_mp_register.h
index 5480ae1..a2087f5 100644
--- a/drivers/staging/sb105x/sb_mp_register.h
+++ b/drivers/staging/sb105x/sb_mp_register.h
@@ -45,7 +45,7 @@
 #define IIR_RS232		0x00		/* RS232 type */
 #define IIR_RS422		0x10		/* RS422 type */
 #define IIR_RS485		0x20		/* RS485 type */
-#define IIR_UNKNOWN		0x30		/* unknown type */
+#define IIR_TYPE_MASK		0x30
 
 /* Interrrupt Mask Register */
 #define MP_OPTR_IMR0		0x0C 	/* port0 ~ port8 */
diff --git a/drivers/staging/sb105x/sb_pci_mp.c b/drivers/staging/sb105x/sb_pci_mp.c
index 131afd0c..3da44df 100644
--- a/drivers/staging/sb105x/sb_pci_mp.c
+++ b/drivers/staging/sb105x/sb_pci_mp.c
@@ -2851,18 +2851,12 @@ static void __init multi_init_ports(void)
 				printk("IIR_RET = %x\n",b_ret);
 			}
 
-			if(IIR_RS232 = (b_ret & IIR_RS232))
-			{
-				mtpt->interface = RS232;
-			}
-			if(IIR_RS422 = (b_ret & IIR_RS422))
-			{
+			/* default to RS232 */
+			mtpt->interface = RS232;
+			if (IIR_RS422 = (b_ret & IIR_TYPE_MASK))
 				mtpt->interface = RS422PTP;
-			}
-			if(IIR_RS485 = (b_ret & IIR_RS485))
-			{
+			if (IIR_RS485 = (b_ret & IIR_TYPE_MASK))
 				mtpt->interface = RS485NE;
-			}
 		}
 	}
 }