diff options
Diffstat (limited to 'drivers/pci/pci.c')
| -rw-r--r-- | drivers/pci/pci.c | 40 |
1 files changed, 30 insertions, 10 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index fac08f508d09..5ba60dd71faa 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -254,20 +254,17 @@ int pci_bus_find_capability(struct pci_bus *bus, unsigned int devfn, int cap) } /** - * pci_find_ext_capability - Find an extended capability + * pci_find_next_ext_capability - Find an extended capability * @dev: PCI device to query + * @start: address at which to start looking (0 to start at beginning of list) * @cap: capability code * - * Returns the address of the requested extended capability structure + * Returns the address of the next matching extended capability structure * within the device's PCI configuration space or 0 if the device does - * not support it. Possible values for @cap: - * - * %PCI_EXT_CAP_ID_ERR Advanced Error Reporting - * %PCI_EXT_CAP_ID_VC Virtual Channel - * %PCI_EXT_CAP_ID_DSN Device Serial Number - * %PCI_EXT_CAP_ID_PWR Power Budgeting + * not support it. Some capabilities can occur several times, e.g., the + * vendor-specific capability, and this provides a way to find them all. */ -int pci_find_ext_capability(struct pci_dev *dev, int cap) +int pci_find_next_ext_capability(struct pci_dev *dev, int start, int cap) { u32 header; int ttl; @@ -279,6 +276,9 @@ int pci_find_ext_capability(struct pci_dev *dev, int cap) if (dev->cfg_size <= PCI_CFG_SPACE_SIZE) return 0; + if (start) + pos = start; + if (pci_read_config_dword(dev, pos, &header) != PCIBIOS_SUCCESSFUL) return 0; @@ -290,7 +290,7 @@ int pci_find_ext_capability(struct pci_dev *dev, int cap) return 0; while (ttl-- > 0) { - if (PCI_EXT_CAP_ID(header) == cap) + if (PCI_EXT_CAP_ID(header) == cap && pos != start) return pos; pos = PCI_EXT_CAP_NEXT(header); @@ -303,6 +303,26 @@ int pci_find_ext_capability(struct pci_dev *dev, int cap) return 0; } +EXPORT_SYMBOL_GPL(pci_find_next_ext_capability); + +/** + * pci_find_ext_capability - Find an extended capability + * @dev: PCI device to query + * @cap: capability code + * + * Returns the address of the requested extended capability structure + * within the device's PCI configuration space or 0 if the device does + * not support it. Possible values for @cap: + * + * %PCI_EXT_CAP_ID_ERR Advanced Error Reporting + * %PCI_EXT_CAP_ID_VC Virtual Channel + * %PCI_EXT_CAP_ID_DSN Device Serial Number + * %PCI_EXT_CAP_ID_PWR Power Budgeting + */ +int pci_find_ext_capability(struct pci_dev *dev, int cap) +{ + return pci_find_next_ext_capability(dev, 0, cap); +} EXPORT_SYMBOL_GPL(pci_find_ext_capability); static int __pci_find_next_ht_cap(struct pci_dev *dev, int pos, int ht_cap) |