Re: [RFC PATCH 1/2] PM: domains: Allow devices attached to genpd to be managed by HW

From: Abel Vesa
Date: Tue Jun 27 2023 - 06:54:18 EST


On 23-06-27 12:46:28, Greg Kroah-Hartman wrote:
> On Tue, Jun 27, 2023 at 01:40:32PM +0300, Abel Vesa wrote:
> > From: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
> >
> > Some power-domains may be capable of relying on the HW to control the power
> > for a device that's hooked up to it. Typically, for these kinds of
> > configurations the device doesn't really need to be attached to a PM domain
> > (genpd), from Linux point of view. However, in some cases the behaviour of
> > the power-domain and its device can be changed in runtime.
> >
> > To allow a consumer driver to change the behaviour of the PM domain for its
> > device, let's provide a new function, dev_pm_genpd_set_hwmode(). Moreover,
> > let's add a corresponding optional genpd callback, ->set_hwmode_dev(),
> > which the genpd provider should implement if it can support switching
> > between HW controlled mode and SW controlled mode.
> >
> > Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
>
> You can't forward on a patch from someone else without also adding your
> signed-off-by on it, right?

Oups, forgot to add it. Will do in the next version.

>
> Also, why is this a RFC series? What is left to do with it to get it
> into a state which you feel comfortable having us review it "for real"?

There is a bit of back story here. This HW control support is something
that Qualcomm platforms support for some of the PDs. Sent this as RFC
as I thought it might open up a discussion of such a generic need at
first. But now that I think of it, it might've been a non-RFC patch as
well.

>
> thanks,
>
> greg k-h