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Date:   Tue, 26 Feb 2019 17:20:11 -0500
From:   "Andrew Jeffery" <andrew@aj.id.au>
To:     "Patrick Venture" <venture@google.com>
Cc:     "Arnd Bergmann" <arnd@arndb.de>,
        "Greg Kroah-Hartman" <gregkh@linuxfoundation.org>,
        "Joel Stanley" <joel@jms.id.au>,
        "Linux Kernel Mailing List" <linux-kernel@vger.kernel.org>,
        linux-arm-kernel@lists.infradead.org, linux-aspeed@lists.ozlabs.org
Subject: Re: [PATCH 2/2] drivers/misc: Add Aspeed P2A control driver
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On Wed, 27 Feb 2019, at 08:26, Patrick Venture wrote:
> On Tue, Feb 26, 2019 at 1:42 PM Patrick Venture <venture@google.com> wrote:
> >
> > On Sun, Feb 24, 2019 at 5:26 PM Andrew Jeffery <andrew@aj.id.au> wrote:
> > >
> >
> > >
> > > > +
> > > > +     /* Access to these needs to be locked, held via probe, mapping ioctl,
> > > > +      * and release, remove.
> > > > +      */
> > > > +     struct mutex tracking;
> > > > +     u32 readers;
> > > > +     u32 readerwriters[P2A_REGION_COUNT];
> > >
> > > Might be better to use refcount_t here instead of u32?
> >
> > Ack
> 
> refcount requires atomic, is that something we have with the ast2400, 2500?

Ah, we do on the 2500 (armv6) but not the 2400 (armv5)