usb:xhci:Fix regression when ATI chipsets detected

The following commit cause a regression on ATI chipsets.
'commit e788787e ("usb:xhci:Add quirk for Certain
failing HP keyboard on reset after resume")'

This causes pinfo->smbus_dev to be wrongly set to NULL on
systems with the ATI chipset that this function checks for first.

Added conditional check for AMD chipsets to avoid the overwriting
pinfo->smbus_dev.
Reported-by: Ben Hutchings <ben@decadent.org.uk>
Fixes: e788787e ("usb:xhci:Add quirk for Certain
failing HP keyboard on reset after resume")
cc: Nehal Shah <Nehal-bakulchandra.Shah@amd.com>
cc: <stable@vger.kernel.org>
Signed-off-by: Sandeep Singh <Sandeep.Singh@amd.com>
Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/host/pci-quirks.c

@@ -142,20 +142,11 @@ static int amd_chipset_sb_type_init(struct amd_chipset_info *pinfo)
 			pinfo->sb_type.gen = AMD_CHIPSET_SB700;
 		else if (rev >= 0x40 && rev <= 0x4f)
 			pinfo->sb_type.gen = AMD_CHIPSET_SB800;
-	}
-	pinfo->smbus_dev = pci_get_device(PCI_VENDOR_ID_AMD,
-					  0x145c, NULL);
-	if (pinfo->smbus_dev) {
-		pinfo->sb_type.gen = AMD_CHIPSET_TAISHAN;
 	} else {
 		pinfo->smbus_dev = pci_get_device(PCI_VENDOR_ID_AMD,
 				PCI_DEVICE_ID_AMD_HUDSON2_SMBUS, NULL);
 
-		if (!pinfo->smbus_dev) {
-			pinfo->sb_type.gen = NOT_AMD_CHIPSET;
-			return 0;
-		}
-
+		if (pinfo->smbus_dev) {
 			rev = pinfo->smbus_dev->revision;
 			if (rev >= 0x11 && rev <= 0x14)
 				pinfo->sb_type.gen = AMD_CHIPSET_HUDSON2;
@@ -163,8 +154,18 @@ static int amd_chipset_sb_type_init(struct amd_chipset_info *pinfo)
 				pinfo->sb_type.gen = AMD_CHIPSET_BOLTON;
 			else if (rev >= 0x39 && rev <= 0x3a)
 				pinfo->sb_type.gen = AMD_CHIPSET_YANGTZE;
+		} else {
+			pinfo->smbus_dev = pci_get_device(PCI_VENDOR_ID_AMD,
+							  0x145c, NULL);
+			if (pinfo->smbus_dev) {
+				rev = pinfo->smbus_dev->revision;
+				pinfo->sb_type.gen = AMD_CHIPSET_TAISHAN;
+			} else {
+				pinfo->sb_type.gen = NOT_AMD_CHIPSET;
+				return 0;
+			}
+		}
 	}
-
 	pinfo->sb_type.rev = rev;
 	return 1;
 }