From: Bjorn Helgaas Date: Wed, 28 Aug 2013 18:01:03 +0000 (-0600) Subject: PCI: Support PCIe Capability Slot registers only for ports with slots X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=6d3a1741f1e648cfbd5a0cc94477a0d5004c6f5e;p=linux-beck.git PCI: Support PCIe Capability Slot registers only for ports with slots Previously we allowed callers to access Slot Capabilities, Status, and Control for Root Ports even if the Root Port did not implement a slot. This seems dubious because the spec only requires these registers if a slot is implemented. It's true that even Root Ports without slots must have *space* for these slot registers, because the Root Capabilities, Status, and Control registers are after the slot registers in the capability. However, for a v1 PCIe Capability, the *semantics* of the slot registers are undefined unless a slot is implemented. Signed-off-by: Bjorn Helgaas Reviewed-By: Jiang Liu --- diff --git a/drivers/pci/access.c b/drivers/pci/access.c index 9a46fa9135d9..061da8c3ab4b 100644 --- a/drivers/pci/access.c +++ b/drivers/pci/access.c @@ -497,9 +497,9 @@ static inline bool pcie_cap_has_sltctl(const struct pci_dev *dev) { int type = pci_pcie_type(dev); - return type == PCI_EXP_TYPE_ROOT_PORT || - (type == PCI_EXP_TYPE_DOWNSTREAM && - pcie_caps_reg(dev) & PCI_EXP_FLAGS_SLOT); + return (type == PCI_EXP_TYPE_ROOT_PORT || + type == PCI_EXP_TYPE_DOWNSTREAM) && + pcie_caps_reg(dev) & PCI_EXP_FLAGS_SLOT; } static inline bool pcie_cap_has_rtctl(const struct pci_dev *dev)