PCI: populate subsystem vendor and device IDs for PCI bridges

Change to populate the subsystem vendor and subsytem device IDs for
PCI-PCI bridges that implement the PCI Subsystem Vendor ID capability.
Previously bridges left subsystem vendor IDs unpopulated.

Signed-off-by: Gabe Black <gabe.black@ni.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

drivers/pci/probe.c

@@ -730,6 +730,7 @@ int pci_setup_device(struct pci_dev *dev)
 	u32 class;
 	u8 hdr_type;
 	struct pci_slot *slot;
+	int pos = 0;
 
 	if (pci_read_config_byte(dev, PCI_HEADER_TYPE, &hdr_type))
 		return -EIO;
@@ -822,6 +823,11 @@ int pci_setup_device(struct pci_dev *dev)
 		dev->transparent = ((dev->class & 0xff) == 1);
 		pci_read_bases(dev, 2, PCI_ROM_ADDRESS1);
 		set_pcie_hotplug_bridge(dev);
+		pos = pci_find_capability(dev, PCI_CAP_ID_SSVID);
+		if (pos) {
+			pci_read_config_word(dev, pos + PCI_SSVID_VENDOR_ID, &dev->subsystem_vendor);
+			pci_read_config_word(dev, pos + PCI_SSVID_DEVICE_ID, &dev->subsystem_device);
+		}
 		break;
 
 	case PCI_HEADER_TYPE_CARDBUS:		    /* CardBus bridge header */

include/linux/pci_regs.h

@@ -365,6 +365,11 @@
 #define  PCI_X_STATUS_266MHZ	0x40000000	/* 266 MHz capable */
 #define  PCI_X_STATUS_533MHZ	0x80000000	/* 533 MHz capable */
 
+/* PCI Bridge Subsystem ID registers */
+
+#define PCI_SSVID_VENDOR_ID     4	/* PCI-Bridge subsystem vendor id register */
+#define PCI_SSVID_DEVICE_ID     6	/* PCI-Bridge subsystem device id register */
+
 /* PCI Express capability registers */
 
 #define PCI_EXP_FLAGS		2	/* Capabilities register */