From 52525b7a3cf82adec5c6cf0ecbd23ff228badc94 Mon Sep 17 00:00:00 2001 From: Kai-Heng Feng Date: Fri, 18 Oct 2019 15:38:47 +0800 Subject: PCI: Add a helper to check Power Resource Requirements _PR3 existence 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 Acked-by: Bjorn Helgaas Link: https://lore.kernel.org/r/20191018073848.14590-1-kai.heng.feng@canonical.com Signed-off-by: Takashi Iwai --- drivers/pci/pci.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'drivers/pci/pci.c') diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index e7982af9a5d8..1df99d9e350e 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -5856,6 +5856,24 @@ int pci_set_vga_state(struct pci_dev *dev, bool decode, return 0; } +#ifdef CONFIG_ACPI +bool pci_pr3_present(struct pci_dev *pdev) +{ + struct acpi_device *adev; + + if (acpi_disabled) + return false; + + adev = ACPI_COMPANION(&pdev->dev); + if (!adev) + return false; + + return adev->power.flags.power_resources && + acpi_has_method(adev->handle, "_PR3"); +} +EXPORT_SYMBOL_GPL(pci_pr3_present); +#endif + /** * pci_add_dma_alias - Add a DMA devfn alias for a device * @dev: the PCI device for which alias is added -- cgit v1.2.3-59-g8ed1b