From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: MIME-Version: 1.0 References: <20180911173050.2374-1-hdegoede@redhat.com> <20180924091841.GG15943@smile.fi.intel.com> <02750104-3029-13df-7506-95416a89d68b@redhat.com> <2073706.oZqG2eVWq3@aspire.rjw.lan> <20181006141651.GW15943@smile.fi.intel.com> In-Reply-To: From: "Rafael J. Wysocki" Date: Thu, 11 Oct 2018 16:00:56 +0200 Message-ID: Subject: Re: [PATCH 2/2] pwm: lpss: Check PWM powerstate after resume on Cherry Trail devices Content-Type: text/plain; charset="UTF-8" List-ID: To: Hans de Goede Cc: Andy Shevchenko , "Rafael J. Wysocki" , Thierry Reding , Linux PWM List , ACPI Devel Maling List On Wed, Oct 10, 2018 at 1:14 PM Hans de Goede wrote: > > Hi, > > On 06-10-18 16:16, Andy Shevchenko wrote: > > On Sat, Oct 06, 2018 at 10:55:41AM +0200, Hans de Goede wrote: > >> On 03-10-18 11:22, Rafael J. Wysocki wrote: > >>> On Monday, September 24, 2018 11:40:14 AM CEST Hans de Goede wrote: > > > >>> Also, why don't you use acpi_device_get_power() instead of evaluating > >>> _PSC directly? It should make no difference if there are no power > >>> resources, should it? > > > >> 2) acpi_device_get_power() is not exported to modules > > > > Do we have any side effects if we just export it? > > I would think exporting is better than open coding. > > acpi_device_get_power() does a lot more then just call the _PSC > method, while as explained we really just want the _PSC method > as that checks the actual D3 bit which we are interested in. > > But as Rafael mentioned if the DSDT does not define power-resources > (which in the 3 DSDTs I just checked it doesn't for the PWM node) then > acpi_device_get_power() is equivalent. > > So I guess I could change this, but I would prefer to stick with > the direct _PSC call. And I would prefer acpi_device_get_power() to be used as long as it works in this case. I really don't want every driver to evaluate ACPI methods directly at will. Thanks, Rafael