Re: [PATCH] PCI: Document connection between pci_power_t and hardware PM capability

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

On Sat, 2016-06-18 at 13:00 -0500, Bjorn Helgaas wrote:
> The dev.pme_support field, pci_pm_init(), and pci_pme_capable() depend
> on
> the fact that the pci_power_t values (PCI_D0, PCI_D1, etc.) match the
> definition of the PME_Support field of the Power Management
> Capabilities
> register in the Power Management capability (see PCI Bus Power
> Management
> spec r1.2, sec 3.2.3).

Nice to know! Thanks.

If it matters:
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

> 
> Add a note to this effect at the pci_power_t typedef.
> 
> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
> ---
>  include/linux/pci.h |    4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index 8597b42..85cede3 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -101,6 +101,10 @@ enum {
>  	DEVICE_COUNT_RESOURCE = PCI_NUM_RESOURCES,
>  };
>  
> +/*
> + * pci_power_t values must match the bits in the PME_Support field of
> the
> + * Power Management Capabilities register in the Power Management
> capability.
> + */
>  typedef int __bitwise pci_power_t;
>  
>  #define PCI_D0		((pci_power_t __force) 0)
> 

-- 

Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Intel Finland Oy