PEP driver for Linux

PEP driver for Linux

[Alex Deucher]

Hi,

I'm trying to understand how to hook in a platform specific driver to
support S0ix on Linux.  Windows defines a platform PEP (power engine
plugin) driver which the platform uses to coordinate the the low power
state of the SoC.  I'm not entirely sure how this would work on Linux.
My understanding is that the all devices go through their suspend
routines and then this PEP driver is responsible for putting the SOC
into it's lowest power state.  On a lot of platforms the PEP driver
interacts with a platform specific ACPI method to tell the platform
which devices are suspended.  I'm not really sure how this should be
handled on Linux.

Thanks,

Alex

Re: PEP driver for Linux

[Rafael J. Wysocki]

On Wed, Nov 20, 2019 at 11:30 PM Alex Deucher <alexdeucher@gmail.com> wrote:
>
> Hi,
>
> I'm trying to understand how to hook in a platform specific driver to
> support S0ix on Linux.  Windows defines a platform PEP (power engine
> plugin) driver which the platform uses to coordinate the the low power
> state of the SoC.  I'm not entirely sure how this would work on Linux.
> My understanding is that the all devices go through their suspend
> routines and then this PEP driver is responsible for putting the SOC
> into it's lowest power state.  On a lot of platforms the PEP driver
> interacts with a platform specific ACPI method to tell the platform
> which devices are suspended.  I'm not really sure how this should be
> handled on Linux.

It is done already, through the PEP device _DSM (see suspend-to-idle
support in drivers/acpi/sleep.c).

Thanks!