diff --git a/drivers/tty/serial/8250/8250_pci.c b/drivers/tty/serial/8250/8250_pci.c
index 4697a514b80a6d2cafcd6a2800d8cdc820c6594f..6063d1512429c9b65743762345d76d362b6a37b7 100644
--- a/drivers/tty/serial/8250/8250_pci.c
+++ b/drivers/tty/serial/8250/8250_pci.c
@@ -1259,10 +1259,10 @@ static int pci_quatech_init(struct pci_dev *dev)
 		unsigned long base = pci_resource_start(dev, 0);
 		if (base) {
 			u32 tmp;
-			outl(inl(base + 0x38), base + 0x38);
+			outl(inl(base + 0x38) | 0x00002000, base + 0x38);
 			tmp = inl(base + 0x3c);
 			outl(tmp | 0x01000000, base + 0x3c);
-			outl(tmp, base + 0x3c);
+			outl(tmp &= ~0x01000000, base + 0x3c);
 		}
 	}
 	return 0;