diff options
Diffstat (limited to 'drivers/pci/pci-acpi.c')
| -rw-r--r-- | drivers/pci/pci-acpi.c | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c index 92384dece4b4..001860361434 100644 --- a/drivers/pci/pci-acpi.c +++ b/drivers/pci/pci-acpi.c @@ -370,6 +370,30 @@ int pci_get_hp_params(struct pci_dev *dev, struct hotplug_params *hpp) EXPORT_SYMBOL_GPL(pci_get_hp_params); /** + * pciehp_is_native - Check whether a hotplug port is handled by the OS + * @pdev: Hotplug port to check + * + * Walk up from @pdev to the host bridge, obtain its cached _OSC Control Field + * and return the value of the "PCI Express Native Hot Plug control" bit. + * On failure to obtain the _OSC Control Field return %false. + */ +bool pciehp_is_native(struct pci_dev *pdev) +{ + struct acpi_pci_root *root; + acpi_handle handle; + + handle = acpi_find_root_bridge_handle(pdev); + if (!handle) + return false; + + root = acpi_pci_find_root(handle); + if (!root) + return false; + + return root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL; +} + +/** * pci_acpi_wake_bus - Root bus wakeup notification fork function. * @work: Work item to handle. */ |