linux-kernel - Re: [PATCH RESEND] mfd: arizona: Fix initialisation of the PM runtime

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Message-ID: <20150812104509.GG18282@x1>
Date:	Wed, 12 Aug 2015 11:45:09 +0100
From:	Lee Jones <lee.jones@...aro.org>
To:	Charles Keepax <ckeepax@...nsource.wolfsonmicro.com>
Cc:	sameo@...ux.intel.com, patches@...nsource.wolfsonmicro.com,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH RESEND] mfd: arizona: Fix initialisation of the PM runtime

On Wed, 12 Aug 2015, Charles Keepax wrote:

> On Wed, Aug 12, 2015 at 09:21:16AM +0100, Lee Jones wrote:
> > On Tue, 11 Aug 2015, Charles Keepax wrote:
> > 
> > > The PM runtime core by default assumes a chip is suspended when runtime
> > > PM is enabled. Currently the arizona driver enables runtime PM when the
> > > chip is fully active and then disables the DCVDD regulator at the end of
> > > arizona_dev_init. This however has several problems, firstly the if we
> > > reach the end of arizona_dev_init, we did not properly follow all the
> > > proceedures for shutting down the chip, and most notably we never marked
> > > the chip as cache only so any writes occuring between then and the next
> > > PM runtime resume will be lost. Secondly, if we are already resumed when
> > > we reach the end of dev_init, then at best we get unbalanced regulator
> > > enable/disables at work we lose DCVDD whilst we need it.
> > > 
> > > Additionally, since the commit 4f0216409f7c ("mfd: arizona: Add better
> > > support for system suspend"), the PM runtime operations may
> > > disable/enable the IRQ, so the IRQs must now be enabled before we call
> > > any PM operations.
> > > 
> > > This patch adds a call to pm_runtime_set_active to inform the PM core
> > > that the device is starting up active and moves the PM enabling to
> > > around the IRQ initialisation to avoid any PM callbacks happening until
> > > the IRQs are initialised.
> > > 
> > > Signed-off-by: Charles Keepax <ckeepax@...nsource.wolfsonmicro.com>
> > > ---
> > > 
> > > This patch was marked as applied on the 24th of June but
> > > doesn't seem to have shown up in your tree yet. Just
> > > resending just in case it got missed as it is a fairly
> > > important bug fix.
> > > 
> > > Thanks,
> > > Charles
> > > 
> > >  drivers/mfd/arizona-core.c |   14 ++++++--------
> > >  1 files changed, 6 insertions(+), 8 deletions(-)
> > 
> > Why are you re-sending this?
> 
> Ah apologies my bad just realised I over looked the patch on your
> fixes branch. I thought it had been missed, sorry for the noise.

If I've sent an "applied, thanks" message and the patch has still not
shown up, it's better to reply directly to it than to send a RESEND.

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
Follow Linaro: Facebook | Twitter | Blog
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