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From:   Linus Walleij <linus.walleij@linaro.org>
Date:   Mon, 19 Nov 2018 13:20:46 +0100
Message-ID: <CACRpkdZD5EurbTRyUg7AWRZqVQ-6rmUQDUmVVCFU3r0Y1bwnVg@mail.gmail.com>
Subject: Re: [PATCH 2/3] pinctrl: stm32: protect configuration registers with
 a hwspinlock
To:     Benjamin Gaignard <benjamin.gaignard@linaro.org>
Cc:     Rob Herring <robh+dt@kernel.org>,
        Alexandre TORGUE <alexandre.torgue@st.com>,
        "open list:GPIO SUBSYSTEM" <linux-gpio@vger.kernel.org>,
        "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
        <devicetree@vger.kernel.org>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        linux-stm32@st-md-mailman.stormreply.com,
        Benjamin Gaignard <benjamin.gaignard@st.com>
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On Tue, Nov 13, 2018 at 10:51 AM Benjamin Gaignard
<benjamin.gaignard@linaro.org> wrote:

> If a hwspinlock if defined in device tree use it to protect
> configuration registers.
>
> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>

Patch applied with Alex' ACK.

Out of curiosity: what is it protecting against?
I would guess simultaneous access from another CPU
but the commit doesn't say.

Simultaneous access from two CPUs makes it extra important
that all register access is read-modify-write, so I'd have a second
check over the code to make sure this is the case.

Yours,
Linus Walleij