sata_sis: fix SCR read breakage

SCR read for controllers which uses PCI configuration space for SCR
access got broken while adding @val argument to SCR accessors.  Fix
it.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/ata/sata_sis.c b/drivers/ata/sata_sis.c
index 8d98a9f..dc8e5c0 100644
--- a/drivers/ata/sata_sis.c
+++ b/drivers/ata/sata_sis.c
@@ -166,11 +166,11 @@
 	return addr;
 }
 
-static u32 sis_scr_cfg_read (struct ata_port *ap, unsigned int sc_reg)
+static u32 sis_scr_cfg_read (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);
-	u32 val, val2 = 0;
+	u32 val2 = 0;
 	u8 pmr;
 
 	if (sc_reg == SCR_ERROR) /* doesn't exist in PCI cfg space */
@@ -178,13 +178,16 @@
 
 	pci_read_config_byte(pdev, SIS_PMR, &pmr);
 
-	pci_read_config_dword(pdev, cfg_addr, &val);
+	pci_read_config_dword(pdev, cfg_addr, val);
 
 	if ((pdev->device == 0x0182) || (pdev->device == 0x0183) ||
 	    (pdev->device == 0x1182) || (pmr & SIS_PMR_COMBINED))
 		pci_read_config_dword(pdev, cfg_addr+0x10, &val2);
 
-	return (val|val2) &  0xfffffffb; /* avoid problems with powerdowned ports */
+	*val |= val2;
+	*val &= 0xfffffffb;	/* avoid problems with powerdowned ports */
+
+	return 0;
 }
 
 static void sis_scr_cfg_write (struct ata_port *ap, unsigned int sc_reg, u32 val)
@@ -214,7 +217,7 @@
 		return -EINVAL;
 
 	if (ap->flags & SIS_FLAG_CFGSCR)
-		return sis_scr_cfg_read(ap, sc_reg);
+		return sis_scr_cfg_read(ap, sc_reg, val);
 
 	pci_read_config_byte(pdev, SIS_PMR, &pmr);