From: "Rafael J. Wysocki" <rjw@sisk.pl>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: [RFC][PATCH 0/2] Make radeonfb use PCI PM core for suspendig device (was: Re: [RFC][PATCH] PCI PM: Be extra careful when changing power states of devices)
Date: Tue, 24 Mar 2009 00:01:33 +0100
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Cc: Jesse Barnes <jbarnes@virtuousgeek.org>,
       Linux PCI <linux-pci@vger.kernel.org>,
       pm list <linux-pm@lists.linux-foundation.org>,
       LKML <linux-kernel@vger.kernel.org>,
       Linus Torvalds <torvalds@linux-foundation.org>,
       Andrew Morton <akpm@linux-foundation.org>
References: <200903210003.55161.rjw@sisk.pl> <200903222208.22434.rjw@sisk.pl> <1237766942.25062.680.camel@pasglop>
In-Reply-To: <1237766942.25062.680.camel@pasglop>
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On Monday 23 March 2009, Benjamin Herrenschmidt wrote:
> On Sun, 2009-03-22 at 22:08 +0100, Rafael J. Wysocki wrote:
> > On Saturday 21 March 2009, Rafael J. Wysocki wrote:
> > > From: Rafael J. Wysocki <rjw@sisk.pl>
> > > 
> > > The story in http://bugzilla.kernel.org/show_bug.cgi?id=12846 shows
> > > that setting the power state of a PCI device by
> > > pci_raw_set_power_state() may sometimes fail.  For this reason,
> > > pci_raw_set_power_state() should not assume that the power state of
> > > the device has actually changed after writing into its PMCSR.
> > > Instead, it should read the value from there and use it to update
> > > dev->current_state.  It also is useful to print a warning if the
> > > device's power state hasn't changed as expected.
> > > 
> > > Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
> > > ---
> > OK, since the Ben's radeonfb fix for bug #12846 has been merged, I'd like
> > to do something a bit different.
> > 
> > Patch 1/2 introduces __pci_set_power_state() that will allow the radeonfb
> > driver not to open code PCI PM operations.
> > 
> > Patch 2/2 makes the driver use __pci_set_power_state().
> > 
> > Comments welcome.
> 
> No objection.

Great, thanks.

I also discussed the patchset with Jesse on IRC and we agreed it was better
than the alternative approaches.  (So, please disregard the patches sent
earlier today).

Would you mind if I put 1/2 and 2/2 into the suspend tree?

Rafael
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