[PATCH v2 8/8] PCI: Align return values of PCIe capability and PCI accessors

[refactormyself]

From: Bolarinwa Olayemi Saheed <refactormyself@xxxxxxxxx>

The PCIe capability accessors can return 0, -EINVAL, or any PCIBIOS_ error
code. PCIBIOS_ error codes have positive values. The PCI accessor on the
other hand can only return 0 or any PCIBIOS_ error code. This
inconsistency among these accessor makes it harder for callers to check 
for errors.

Return PCIBIOS_BAD_REGISTER_NUMBER instead of -EINVAL in all PCIe
capability accessors.

Suggested-by: Bjorn Helgaas <bjorn@xxxxxxxxxxx>
Signed-off-by: Bolarinwa Olayemi Saheed <refactormyself@xxxxxxxxx>
---
 drivers/pci/access.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/pci/access.c b/drivers/pci/access.c
index 79c4a2ef269a..cbb3804903a0 100644
--- a/drivers/pci/access.c
+++ b/drivers/pci/access.c
@@ -409,7 +409,7 @@ int pcie_capability_read_word(struct pci_dev *dev, int pos, u16 *val)
 
 	*val = 0;
 	if (pos & 1)
-		return -EINVAL;
+		return PCIBIOS_BAD_REGISTER_NUMBER;
 
 	if (pcie_capability_reg_implemented(dev, pos)) {
 		ret = pci_read_config_word(dev, pci_pcie_cap(dev) + pos, val);
@@ -444,7 +444,7 @@ int pcie_capability_read_dword(struct pci_dev *dev, int pos, u32 *val)
 
 	*val = 0;
 	if (pos & 3)
-		return -EINVAL;
+		return PCIBIOS_BAD_REGISTER_NUMBER;
 
 	if (pcie_capability_reg_implemented(dev, pos)) {
 		ret = pci_read_config_dword(dev, pci_pcie_cap(dev) + pos, val);
@@ -469,7 +469,7 @@ EXPORT_SYMBOL(pcie_capability_read_dword);
 int pcie_capability_write_word(struct pci_dev *dev, int pos, u16 val)
 {
 	if (pos & 1)
-		return -EINVAL;
+		return PCIBIOS_BAD_REGISTER_NUMBER;
 
 	if (!pcie_capability_reg_implemented(dev, pos))
 		return 0;
@@ -481,7 +481,7 @@ EXPORT_SYMBOL(pcie_capability_write_word);
 int pcie_capability_write_dword(struct pci_dev *dev, int pos, u32 val)
 {
 	if (pos & 3)
-		return -EINVAL;
+		return PCIBIOS_BAD_REGISTER_NUMBER;
 
 	if (!pcie_capability_reg_implemented(dev, pos))
 		return 0;
-- 
2.18.2