Commit 52525b7a authored by Kai-Heng Feng's avatar Kai-Heng Feng Committed by Takashi Iwai
Browse files

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: default avatarKai-Heng Feng <kai.heng.feng@canonical.com>
Acked-by: default avatarBjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/20191018073848.14590-1-kai.heng.feng@canonical.com


Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
parent acfedcbe

drivers/pci/pci.c

+18 −0
Original line number Diff line number Diff line
@@ -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

include/linux/pci.h

+2 −0
Original line number Diff line number Diff line
@@ -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

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