linux-kernel - Re: [PATCH v1] spi: spi-topcliff-pch: use generic power management

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Date:   Mon, 27 Jul 2020 12:36:52 +0530
From:   Vaibhav Gupta <vaibhavgupta40@...il.com>
To:     Andy Shevchenko <andy.shevchenko@...il.com>
Cc:     Bjorn Helgaas <helgaas@...nel.org>,
        Bjorn Helgaas <bhelgaas@...gle.com>,
        Bjorn Helgaas <bjorn@...gaas.com>,
        Vaibhav Gupta <vaibhav.varodek@...il.com>,
        Mark Brown <broonie@...nel.org>,
        linux-spi <linux-spi@...r.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        linux-kernel-mentees@...ts.linuxfoundation.org,
        Shuah Khan <skhan@...uxfoundation.org>,
        "Rafael J. Wysocki" <rjw@...ysocki.net>
Subject: Re: [PATCH v1] spi: spi-topcliff-pch: use generic power management

On Sat, Jul 25, 2020 at 01:44:44PM +0300, Andy Shevchenko wrote:
> On Sat, Jul 25, 2020 at 1:42 PM Andy Shevchenko
> <andy.shevchenko@...il.com> wrote:
> > On Sat, Jul 25, 2020 at 1:37 AM Bjorn Helgaas <helgaas@...nel.org> wrote:
> > > On Fri, Jul 24, 2020 at 11:16:55PM +0300, Andy Shevchenko wrote:
> 
> ...
> 
> > > If it's a bug that spi-topcliff-pch.c disables but never enables
> > > wakeup, I think this should turn into two patches:
> > >
> > >   1) Fix the bug by enabling wakeup in suspend (or whatever the right
> > >   fix is), and
> > >
> > >   2) Convert to generic PM, which may involve removing the
> > >   wakeup-related code completely.
> >
> > Works for me.
> 
> The only problem here, is that the 2nd is already in the Mark's tree
> and he doesn't do rebases.
> So, it will be the other way around.
>
Concluding from yours and Bjorn's suggestion, I will drop the
device_wakeup_disable() call form .resume() and send the fix. I will also track
the drivers who got similar upgrades and went un-noticed.

As Bjorn mentioned, the problem is that I don't have hardware to test, so I just
replicated the legacy behaviour in generic by replacing
pci_enable_wake(....,false) with device_wakeup_disable().

So, from now, while upgrading drivers with generic PM, should I completely drop
the pci_enable_wake(....,false) calls if both .suspend() and .resume() try to
wakeup-disable the device?

Thanks
Vaibhav Gupta
> 
> -- 
> With Best Regards,
> Andy Shevchenko