Re: Time to re-enable Runtime PM per default for PCI devcies?

From: Lukas Wunner
Date: Wed Dec 30 2020 - 23:34:27 EST


On Wed, Dec 30, 2020 at 11:56:04PM +0100, Heiner Kallweit wrote:
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -3024,7 +3024,9 @@ void pci_pm_init(struct pci_dev *dev)
> u16 status;
> u16 pmc;
>
> - pm_runtime_forbid(&dev->dev);
> + if (pci_acpi_forbid_runtime_pm())
> + pm_runtime_forbid(&dev->dev);
> +

Generic PCI code usually does not call ACPI-specific functions directly,
but rather through a pci_platform_pm_ops callback.

FWIW, if platform_pci_power_manageable() returns true, it can probably
be assumed that allowing runtime PM by default is okay. So as a first
step, you may want to call that instead of adding a new callback.

Thanks,

Lukas