[v2,02/13] PCI: Introduce new pci_is_bridge() helper function

Commit Message

Yijing Wang May 4, 2014, 4:23 a.m. UTC

PCIe Spec define the PCI bridge is the PCI device
which header type(bit 0 through 6) is 0x1(PCI bridge)
or 0x2(CardBus bridge).

Signed-off-by: Yijing Wang <[e-mail]>
---
 include/linux/pci.h |   13 +++++++++++++
 1 files changed, 13 insertions(+), 0 deletions(-)

Patch

diff --git a/include/linux/pci.h b/include/linux/pci.h
index aab57b4..9f5f89e 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -477,6 +477,19 @@  static inline bool pci_is_root_bus(struct pci_bus *pbus)
 	return !(pbus->parent);
 }
 
+/**
+ * pci_is_bridge - check if the PCI device is a bridge
+ * @dev: PCI device
+ *
+ * Return true if the PCI device is bridge whether it has subordinate
+ * or not.
+ */
+static inline bool pci_is_bridge(struct pci_dev *dev)
+{
+	return dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
+		dev->hdr_type == PCI_HEADER_TYPE_CARDBUS;
+}
+
 static inline struct pci_dev *pci_upstream_bridge(struct pci_dev *dev)
 {
 	dev = pci_physfn(dev);