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 <kai.heng.feng@canonical.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/20191018073848.14590-1-kai.heng.feng@canonical.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Kai-Heng Feng 2019-10-18 15:38:47 +08:00 committed by Takashi Iwai
parent acfedcbe1c
commit 52525b7a3c
2 changed files with 20 additions and 0 deletions

View File

@ -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

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@ -2310,9 +2310,11 @@ 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