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From:   Wei Wang <wvw@google.com>
Date:   Tue, 10 Dec 2019 12:01:32 -0800
Message-ID: <CAGXk5yrsmvHK_xwvp_kFNmSqKOZ7Ef3HrVBHYDMBmDsCz0FNSQ@mail.gmail.com>
Subject: Re: [PATCH v3 0/3] thermal: introduce by-name softlink
To:     Daniel Lezcano <daniel.lezcano@linaro.org>
Cc:     Wei Wang <wei.vince.wang@gmail.com>,
        Zhang Rui <rui.zhang@intel.com>,
        Eduardo Valentin <edubezval@gmail.com>,
        Amit Kucheria <amit.kucheria@verdurent.com>,
        Linux PM list <linux-pm@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>
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On Tue, Dec 10, 2019 at 6:36 AM Daniel Lezcano
<daniel.lezcano@linaro.org> wrote:
>
> On 05/12/2019 08:19, Wei Wang wrote:
> > The paths thermal_zone%d and cooling_device%d are not intuitive and the
> > numbers are subject to change due to device tree change. This usually
> > leads to tree traversal in userspace code.
> > The patch creates `tz-by-name' and `cdev-by-name' for thermal zone and
> > cooling_device respectively.
>
> Instead of adding another ABI, I suggest we put the current one
> deprecated with a warning in the dmesg, update the documentation and
> change the name the next version.
>
>

IMHO, we should keep the existing path which is a common pattern for
sysfs interface. There are reasons we need couple thermal zone and
cooling device in one class, but might be worth considering split as
the latter might be used for other purposes e.g. battery current limit
for preventive vdrop prevention. By nature, thermal zone are sensors,
and cooling devices are usually components with potential high power
use.


> > Changes since v1 [1]:
> >  * Split cooling device registration into a seperate patch
> > Changes since v2 [2]:
> >  * Split improve error message in thermal zone registration
> >
> > [1]: v1: https://lore.kernel.org/patchwork/patch/1139450/
> > [2]: v2: https://lkml.org/lkml/2019/12/4/1291
> >
> > Wei Wang (3):
> >   thermal: prevent cooling device with no type to be registered
> >   thermal: improve error message in thermal zone registration
> >   thermal: create softlink by name for thermal_zone and cooling_device
> >
> >  drivers/thermal/thermal_core.c | 55 +++++++++++++++++++++++++++-------
> >  1 file changed, 44 insertions(+), 11 deletions(-)
> >
>
>
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