[Public] > -----Original Message----- > From: Lukas Wunner <lukas@xxxxxxxxx> > Sent: Monday, March 14, 2022 04:13 > To: Limonciello, Mario <Mario.Limonciello@xxxxxxx> > Cc: Hans de Goede <hdegoede@xxxxxxxxxx>; Mark Gross > <mgross@xxxxxxxxxxxxxxx>; Rafael J . Wysocki <rjw@xxxxxxxxxxxxx>; open > list:X86 PLATFORM DRIVERS <platform-driver-x86@xxxxxxxxxxxxxxx>; linux- > acpi@xxxxxxxxxxxxxxx; S-k, Shyam-sundar <Shyam-sundar.S-k@xxxxxxx>; > Goswami, Sanket <Sanket.Goswami@xxxxxxx> > Subject: Re: [PATCH v3 1/5] ACPI / x86: Add support for LPS0 callback handler > > On Mon, Mar 14, 2022 at 12:03:35AM -0500, Mario Limonciello wrote: > > Currenty the latest thing run during a suspend to idle attempt is > > the LPS0 `prepare_late` callback and the earliest thing is the > > `resume_early` callback. > > > > There is a desire for the `amd-pmc` driver to suspend later in the > > suspend process (ideally the very last thing), so create a callback > > that it or any other driver can hook into to do this. > > I'm wondering if this can be solved with much less code by either > using device links (a device link to amd-pmc from everything that > needs to be suspended before it), or with a notifier chain? > I don't believe that device links will work well here - the LPS0 "prepare_late" happens after all device suspend routines are already done. Notifier chains would probably work, but I'm not convinced they will be much less code. As I already have everything working with the current patch series before I try I'd like to know what Rafael prefers that for this purpose.
