diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
index 77baff022f71b85259e1e064a06531b03a9bb727..00a9947cb7cc6d0af342736ed121d46f14ee9caf 100644
--- a/drivers/pci/pci-sysfs.c
+++ b/drivers/pci/pci-sysfs.c
@@ -715,7 +715,7 @@ static struct bin_attribute pci_config_attr = {
 		.name = "config",
 		.mode = S_IRUGO | S_IWUSR,
 	},
-	.size = 256,
+	.size = PCI_CFG_SPACE_SIZE,
 	.read = pci_read_config,
 	.write = pci_write_config,
 };
@@ -725,7 +725,7 @@ static struct bin_attribute pcie_config_attr = {
 		.name = "config",
 		.mode = S_IRUGO | S_IWUSR,
 	},
-	.size = 4096,
+	.size = PCI_CFG_SPACE_EXP_SIZE,
 	.read = pci_read_config,
 	.write = pci_write_config,
 };
@@ -743,7 +743,7 @@ int __must_check pci_create_sysfs_dev_files (struct pci_dev *pdev)
 	if (!sysfs_initialized)
 		return -EACCES;
 
-	if (pdev->cfg_size < 4096)
+	if (pdev->cfg_size < PCI_CFG_SPACE_EXP_SIZE)
 		retval = sysfs_create_bin_file(&pdev->dev.kobj, &pci_config_attr);
 	else
 		retval = sysfs_create_bin_file(&pdev->dev.kobj, &pcie_config_attr);
@@ -814,7 +814,7 @@ int __must_check pci_create_sysfs_dev_files (struct pci_dev *pdev)
 		kfree(pdev->vpd->attr);
 	}
 err_config_file:
-	if (pdev->cfg_size < 4096)
+	if (pdev->cfg_size < PCI_CFG_SPACE_EXP_SIZE)
 		sysfs_remove_bin_file(&pdev->dev.kobj, &pci_config_attr);
 	else
 		sysfs_remove_bin_file(&pdev->dev.kobj, &pcie_config_attr);
@@ -839,7 +839,7 @@ void pci_remove_sysfs_dev_files(struct pci_dev *pdev)
 		sysfs_remove_bin_file(&pdev->dev.kobj, pdev->vpd->attr);
 		kfree(pdev->vpd->attr);
 	}
-	if (pdev->cfg_size < 4096)
+	if (pdev->cfg_size < PCI_CFG_SPACE_EXP_SIZE)
 		sysfs_remove_bin_file(&pdev->dev.kobj, &pci_config_attr);
 	else
 		sysfs_remove_bin_file(&pdev->dev.kobj, &pcie_config_attr);
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 09dc893c81db827f12d47f4f8f1cb379e4e8729c..553ca6657955597d7c18d6c9688b822a5d925b32 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -213,10 +213,13 @@ int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap)
 int pci_find_ext_capability(struct pci_dev *dev, int cap)
 {
 	u32 header;
-	int ttl = 480; /* 3840 bytes, minimum 8 bytes per capability */
-	int pos = 0x100;
+	int ttl;
+	int pos = PCI_CFG_SPACE_SIZE;
 
-	if (dev->cfg_size <= 256)
+	/* minimum 8 bytes per capability */
+	ttl = (PCI_CFG_SPACE_EXP_SIZE - PCI_CFG_SPACE_SIZE) / 8;
+
+	if (dev->cfg_size <= PCI_CFG_SPACE_SIZE)
 		return 0;
 
 	if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
@@ -234,7 +237,7 @@ int pci_find_ext_capability(struct pci_dev *dev, int cap)
 			return pos;
 
 		pos = PCI_EXT_CAP_NEXT(header);
-		if (pos < 0x100)
+		if (pos < PCI_CFG_SPACE_SIZE)
 			break;
 
 		if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL)
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 4723b12fb39a8e9a22c7e33a28b0df4efb5ef1eb..601abdc8dd9f1683aee87a2cbcd29b74fdbc8337 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -1,3 +1,9 @@
+#ifndef DRIVERS_PCI_H
+#define DRIVERS_PCI_H
+
+#define PCI_CFG_SPACE_SIZE	256
+#define PCI_CFG_SPACE_EXP_SIZE	4096
+
 /* Functions internal to the PCI core code */
 
 extern int pci_uevent(struct device *dev, struct kobj_uevent_env *env);
@@ -145,3 +151,4 @@ struct pci_slot_attribute {
 };
 #define to_pci_slot_attr(s) container_of(s, struct pci_slot_attribute, attr)
 
+#endif /* DRIVERS_PCI_H */
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 7aa71636dd3c3d7534a1e0fd47156a8e1a6a7ee4..f6754e87f046e5145e8ec4f576061382954c8576 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -14,8 +14,6 @@
 
 #define CARDBUS_LATENCY_TIMER	176	/* secondary latency timer */
 #define CARDBUS_RESERVE_BUSNR	3
-#define PCI_CFG_SPACE_SIZE	256
-#define PCI_CFG_SPACE_EXP_SIZE	4096
 
 /* Ugh.  Need to stop exporting this to modules. */
 LIST_HEAD(pci_root_buses);
@@ -887,8 +885,9 @@ static void set_pcie_port_type(struct pci_dev *pdev)
 int pci_cfg_space_size_ext(struct pci_dev *dev)
 {
 	u32 status;
+	int pos = PCI_CFG_SPACE_SIZE;
 
-	if (pci_read_config_dword(dev, 256, &status) != PCIBIOS_SUCCESSFUL)
+	if (pci_read_config_dword(dev, pos, &status) != PCIBIOS_SUCCESSFUL)
 		goto fail;
 	if (status == 0xffffffff)
 		goto fail;