PCI: introduce pci_pcie_cap()

Introduce pci_pcie_cap() API that returns saved PCIe capability offset
(currently it is saved in 'pcie_cap' field in the struct PCI dev).
Using pci_pcie_cap() instead of pci_find_capability() avoids
unnecessary search in PCI configuration space.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This commit is contained in:
Kenji Kaneshige 2009-11-11 14:29:54 +09:00 committed by Jesse Barnes
parent 8c8def26bf
commit d7b7e60526
1 changed files with 16 additions and 0 deletions

View File

@ -1301,5 +1301,21 @@ extern void pci_hp_create_module_link(struct pci_slot *pci_slot);
extern void pci_hp_remove_module_link(struct pci_slot *pci_slot);
#endif
/**
* pci_pcie_cap - get the saved PCIe capability offset
* @dev: PCI device
*
* PCIe capability offset is calculated at PCI device initialization
* time and saved in the data structure. This function returns saved
* PCIe capability offset. Using this instead of pci_find_capability()
* reduces unnecessary search in the PCI configuration space. If you
* need to calculate PCIe capability offset from raw device for some
* reasons, please use pci_find_capability() instead.
*/
static inline int pci_pcie_cap(struct pci_dev *dev)
{
return dev->pcie_cap;
}
#endif /* __KERNEL__ */
#endif /* LINUX_PCI_H */