Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
MIME-Version: 1.0
References: <20200309045411.21859-1-andy.tang@nxp.com> <18c58e1b-583c-2308-ee60-a8923c2027ee@linaro.org>
 <CAHLCerPBxe=Az=EexxYQkgvhRO40JT0qEhnAwqnGbeesiU-bnQ@mail.gmail.com>
In-Reply-To: <CAHLCerPBxe=Az=EexxYQkgvhRO40JT0qEhnAwqnGbeesiU-bnQ@mail.gmail.com>
From:   Amit Kucheria <amit.kucheria@linaro.org>
Date:   Wed, 25 Mar 2020 12:07:04 +0530
Message-ID: <CAHLCerN6ccJ7zbj9uYKGp-b05q1o7HsaUyW_oTZmEJX1EWXWQQ@mail.gmail.com>
Subject: Re: [PATCH] dt-bindings: thermal: make cooling-maps property optional
To:     Daniel Lezcano <daniel.lezcano@linaro.org>
Cc:     Yuantian Tang <andy.tang@nxp.com>, Zhang Rui <rui.zhang@intel.com>,
        Linux PM list <linux-pm@vger.kernel.org>,
        "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" 
        <devicetree@vger.kernel.org>, LKML <linux-kernel@vger.kernel.org>
Content-Type: text/plain; charset="UTF-8"
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Mon, Mar 16, 2020 at 9:43 PM Amit Kucheria <amit.kucheria@linaro.org> wrote:
>
> On Mon, Mar 16, 2020 at 8:22 PM Daniel Lezcano
> <daniel.lezcano@linaro.org> wrote:
> >
> > On 09/03/2020 05:54, andy.tang@nxp.com wrote:
> > > From: Yuantian Tang <andy.tang@nxp.com>
> > >
> > > Cooling-maps doesn't have to be a required property because there may
> > > be no cooling device on system, or there are no enough cooling devices for
> > > each thermal zone in multiple thermal zone cases since cooling devices
> > > can't be shared.
> > > So make this property optional to remove such limitations.
> > >
> > > For thermal zones with no cooling-maps, there could be critic trips
> > > that can trigger CPU reset or shutdown. So they still can take actions.
> > >
> > > Signed-off-by: Yuantian Tang <andy.tang@nxp.com>
>
> Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
>
> >
> > Amit, I'm about to pick this patch, it will collide with the yaml
> > conversion changes.
>
> Thanks for the headsup. I can fixup v3 when I respin.
>
> However, I've always interpreted this binding as follows:
> - cooling-maps should be mandatory for active and passive trip types
> otherwise there will be no cooling
> - cooling-maps make no sense for critical trip type since we're
> invoking system shutdown
> - cooling-maps are optional for hot trip types.
>
> Is this your understanding too?
>
> We should be able to enforce this in YAML.

Rui, Daniel,

What do you think about the above interpretation of the cooling-maps bindings?

Regards,
Amit