On Wed, Sep 25, 2019 at 07:43:53PM +0800, Kai-Heng Feng wrote:
> Add pci_pr3_present() to check whether the platform supplies _PR3 to
> tell us which power resources the device depends on when in D3hot. This
> information is useful to let drivers 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@xxxxxxxxxxxxx>
Acked-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
I assume Takashi will merge this along with the ALSA patch.
> ---
> v5:
> - Add wording suggestion from Bjorn.
> v4:
> - Let caller to find its upstream port device.
>
> drivers/pci/pci.c | 16 ++++++++++++++++
> include/linux/pci.h | 2 ++
> 2 files changed, 18 insertions(+)
>
> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
> index e7982af9a5d8..d03f624d8928 100644
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -5856,6 +5856,22 @@ int pci_set_vga_state(struct pci_dev *dev, bool decode,
> return 0;
> }
>
> +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);
> +
> /**
> * 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 f9088c89a534..1d15c5d49cdd 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -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
> --
> 2.17.1
>
