diff --git a/drivers/ata/sata_sis.c b/drivers/ata/sata_sis.c
index 6b8e45b..1010b30 100644
--- a/drivers/ata/sata_sis.c
+++ b/drivers/ata/sata_sis.c
@@ -142,7 +142,7 @@
 	u8 pmr;
 
 	if (sc_reg == SCR_ERROR) /* doesn't exist in PCI cfg space */
-		return 0xffffffff;
+		return -EINVAL;
 
 	pci_read_config_byte(pdev, SIS_PMR, &pmr);
 
@@ -158,14 +158,14 @@
 	return 0;
 }
 
-static void sis_scr_cfg_write(struct ata_port *ap, unsigned int sc_reg, u32 val)
+static int sis_scr_cfg_write(struct ata_port *ap, unsigned int sc_reg, u32 val)
 {
 	struct pci_dev *pdev = to_pci_dev(ap->host->dev);
 	unsigned int cfg_addr = get_scr_cfg_addr(ap, sc_reg);
 	u8 pmr;
 
 	if (sc_reg == SCR_ERROR) /* doesn't exist in PCI cfg space */
-		return;
+		return -EINVAL;
 
 	pci_read_config_byte(pdev, SIS_PMR, &pmr);
 
@@ -174,6 +174,8 @@
 	if ((pdev->device == 0x0182) || (pdev->device == 0x0183) ||
 	    (pdev->device == 0x1182) || (pmr & SIS_PMR_COMBINED))
 		pci_write_config_dword(pdev, cfg_addr+0x10, val);
+
+	return 0;
 }
 
 static int sis_scr_read(struct ata_port *ap, unsigned int sc_reg, u32 *val)
@@ -211,14 +213,14 @@
 	pci_read_config_byte(pdev, SIS_PMR, &pmr);
 
 	if (ap->flags & SIS_FLAG_CFGSCR)
-		sis_scr_cfg_write(ap, sc_reg, val);
+		return sis_scr_cfg_write(ap, sc_reg, val);
 	else {
 		iowrite32(val, ap->ioaddr.scr_addr + (sc_reg * 4));
 		if ((pdev->device == 0x0182) || (pdev->device == 0x0183) ||
 		    (pdev->device == 0x1182) || (pmr & SIS_PMR_COMBINED))
 			iowrite32(val, ap->ioaddr.scr_addr + (sc_reg * 4)+0x10);
+		return 0;
 	}
-	return 0;
 }
 
 static int sis_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)