A driver may want to know the existence of _PR3, to choose different runtime suspend behavior. A user will be add in next patch.
This is mostly the same as nouveau_pr3_present().
Signed-off-by: Kai-Heng Feng kai.heng.feng@canonical.com --- drivers/pci/pci.c | 20 ++++++++++++++++++++ include/linux/pci.h | 2 ++ 2 files changed, 22 insertions(+)
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 1b27b5af3d55..776af15b92c2 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -5856,6 +5856,26 @@ int pci_set_vga_state(struct pci_dev *dev, bool decode, return 0; }
+bool pci_pr3_present(struct pci_dev *pdev) +{ + struct pci_dev *parent_pdev = pci_upstream_bridge(pdev); + struct acpi_device *parent_adev; + + if (acpi_disabled) + return false; + + if (!parent_pdev) + return false; + + parent_adev = ACPI_COMPANION(&parent_pdev->dev); + if (!parent_adev) + return false; + + return parent_adev->power.flags.power_resources && + acpi_has_method(parent_adev->handle, "_PR3"); +} +EXPORT_SYMBOL_GPL(pci_pr3_present); + /** * pci_add_dma_alias - Add a DMA devfn alias for a device * @dev: the PCI device for which alias is added diff --git a/include/linux/pci.h b/include/linux/pci.h index 82e4cd1b7ac3..9b6f7b67fac9 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -2348,9 +2348,11 @@ struct irq_domain *pci_host_bridge_acpi_msi_domain(struct pci_bus *bus);
void pci_msi_register_fwnode_provider(struct fwnode_handle *(*fn)(struct device *)); +bool pci_pr3_present(struct pci_dev *pdev); #else static inline struct irq_domain * pci_host_bridge_acpi_msi_domain(struct pci_bus *bus) { return NULL; } +static bool pci_pr3_present(struct pci_dev *pdev) { return false; } #endif
#ifdef CONFIG_EEH