From: Eduardo Valentin <edubezval-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
To: Leo Yan <leo.yan-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
Cc: Wei Xu <xuwei5-C8/M+/jPZTeaMJb+Lgu22Q@public.gmane.org>,
Rob Herring <robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>,
Pawel Moll <pawel.moll-5wv7dgnIgG8@public.gmane.org>,
Mark Rutland <mark.rutland-5wv7dgnIgG8@public.gmane.org>,
Ian Campbell
<ijc+devicetree-KcIKpvwj1kUDXYZnReoRVg@public.gmane.org>,
Kumar Gala <galak-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org>,
Catalin Marinas <catalin.marinas-5wv7dgnIgG8@public.gmane.org>,
Will Deacon <will.deacon-5wv7dgnIgG8@public.gmane.org>,
Zhang Rui <rui.zhang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>,
kongxinwei
<kong.kongxinwei-C8/M+/jPZTeaMJb+Lgu22Q@public.gmane.org>,
Javi Merino <javi.merino-5wv7dgnIgG8@public.gmane.org>,
Punit Agrawal <Punit.Agrawal-5wv7dgnIgG8@public.gmane.org>,
linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org,
devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
linux-pm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Subject: Re: [PATCH v2 1/5] thermal: change "hysteresis" as optional property
Date: Thu, 3 Mar 2016 08:29:44 -0800 [thread overview]
Message-ID: <20160303162942.GA2445@localhost.localdomain> (raw)
In-Reply-To: <1456458227-12950-2-git-send-email-leo.yan-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
Hi Leo,
On Fri, Feb 26, 2016 at 11:43:43AM +0800, Leo Yan wrote:
> The property "hysteresis" is mandatory for trip points, so if without
> it the thermal zone cannot register successfully. But "hysteresis" is
> ignored in the thermal subsystem and only inquired by several thermal
> sensor drivers.
I am not sure this a good direction to go. Remember that Linux
implementation not necessarily has to be the implication of the DT
binding. Hysteresis is a property that plays a significant role on
thermal control systems, which in many cases avoid overshooting cooling
actions. Having the DT writer to explicitly set it to 0 means that zone
does not suffer of overshooting and does not need hysteresis.
If the Linux thermal subsystem has a problem with handling hysteresis, I
would rather fix Linux code than relaxing the DT binding. Or if you
still believe hysteresis is really optional, I would prefer to see a
better justification than "Linux ignores it".
BR,
Eduardo
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
WARNING: multiple messages have this Message-ID (diff)
From: edubezval@gmail.com (Eduardo Valentin)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH v2 1/5] thermal: change "hysteresis" as optional property
Date: Thu, 3 Mar 2016 08:29:44 -0800 [thread overview]
Message-ID: <20160303162942.GA2445@localhost.localdomain> (raw)
In-Reply-To: <1456458227-12950-2-git-send-email-leo.yan@linaro.org>
Hi Leo,
On Fri, Feb 26, 2016 at 11:43:43AM +0800, Leo Yan wrote:
> The property "hysteresis" is mandatory for trip points, so if without
> it the thermal zone cannot register successfully. But "hysteresis" is
> ignored in the thermal subsystem and only inquired by several thermal
> sensor drivers.
I am not sure this a good direction to go. Remember that Linux
implementation not necessarily has to be the implication of the DT
binding. Hysteresis is a property that plays a significant role on
thermal control systems, which in many cases avoid overshooting cooling
actions. Having the DT writer to explicitly set it to 0 means that zone
does not suffer of overshooting and does not need hysteresis.
If the Linux thermal subsystem has a problem with handling hysteresis, I
would rather fix Linux code than relaxing the DT binding. Or if you
still believe hysteresis is really optional, I would prefer to see a
better justification than "Linux ignores it".
BR,
Eduardo
WARNING: multiple messages have this Message-ID (diff)
From: Eduardo Valentin <edubezval@gmail.com>
To: Leo Yan <leo.yan@linaro.org>
Cc: Wei Xu <xuwei5@hisilicon.com>, Rob Herring <robh+dt@kernel.org>,
Pawel Moll <pawel.moll@arm.com>,
Mark Rutland <mark.rutland@arm.com>,
Ian Campbell <ijc+devicetree@hellion.org.uk>,
Kumar Gala <galak@codeaurora.org>,
Catalin Marinas <catalin.marinas@arm.com>,
Will Deacon <will.deacon@arm.com>,
Zhang Rui <rui.zhang@intel.com>,
kongxinwei <kong.kongxinwei@hisilicon.com>,
Javi Merino <javi.merino@arm.com>,
Punit Agrawal <Punit.Agrawal@arm.com>,
linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org,
linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org
Subject: Re: [PATCH v2 1/5] thermal: change "hysteresis" as optional property
Date: Thu, 3 Mar 2016 08:29:44 -0800 [thread overview]
Message-ID: <20160303162942.GA2445@localhost.localdomain> (raw)
In-Reply-To: <1456458227-12950-2-git-send-email-leo.yan@linaro.org>
Hi Leo,
On Fri, Feb 26, 2016 at 11:43:43AM +0800, Leo Yan wrote:
> The property "hysteresis" is mandatory for trip points, so if without
> it the thermal zone cannot register successfully. But "hysteresis" is
> ignored in the thermal subsystem and only inquired by several thermal
> sensor drivers.
I am not sure this a good direction to go. Remember that Linux
implementation not necessarily has to be the implication of the DT
binding. Hysteresis is a property that plays a significant role on
thermal control systems, which in many cases avoid overshooting cooling
actions. Having the DT writer to explicitly set it to 0 means that zone
does not suffer of overshooting and does not need hysteresis.
If the Linux thermal subsystem has a problem with handling hysteresis, I
would rather fix Linux code than relaxing the DT binding. Or if you
still believe hysteresis is really optional, I would prefer to see a
better justification than "Linux ignores it".
BR,
Eduardo
next prev parent reply other threads:[~2016-03-03 16:29 UTC|newest]
Thread overview: 31+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-02-26 3:43 [PATCH v2 0/5] thermal: hisilicon: enable power allocator for Hi6220 Leo Yan
2016-02-26 3:43 ` Leo Yan
2016-02-26 3:43 ` Leo Yan
2016-02-26 3:43 ` [PATCH v2 1/5] thermal: change "hysteresis" as optional property Leo Yan
2016-02-26 3:43 ` Leo Yan
[not found] ` <1456458227-12950-2-git-send-email-leo.yan-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
2016-03-03 10:45 ` Javi Merino
2016-03-03 10:45 ` Javi Merino
2016-03-03 10:45 ` Javi Merino
2016-03-03 16:29 ` Eduardo Valentin [this message]
2016-03-03 16:29 ` Eduardo Valentin
2016-03-03 16:29 ` Eduardo Valentin
2016-03-04 3:03 ` Leo Yan
2016-03-04 3:03 ` Leo Yan
2016-03-04 11:57 ` Javi Merino
2016-03-04 11:57 ` Javi Merino
2016-03-08 13:57 ` Leo Yan
2016-03-08 13:57 ` Leo Yan
2016-03-08 20:55 ` Eduardo Valentin
2016-03-08 20:55 ` Eduardo Valentin
2016-03-09 11:10 ` Javi Merino
2016-03-09 11:10 ` Javi Merino
2016-03-20 15:40 ` Leo Yan
2016-03-20 15:40 ` Leo Yan
2016-02-26 3:43 ` [PATCH v2 2/5] thermal: hisilicon: support to use any sensor Leo Yan
2016-02-26 3:43 ` Leo Yan
2016-02-26 3:43 ` [PATCH v2 3/5] thermal: hisilicon: fix IRQ imbalance enabling Leo Yan
2016-02-26 3:43 ` Leo Yan
2016-02-26 3:43 ` [PATCH v2 4/5] arm64: dts: register Hi6220's thermal sensor Leo Yan
2016-02-26 3:43 ` Leo Yan
2016-02-26 3:43 ` [PATCH v2 5/5] arm64: dts: register Hi6220's thermal zone for power allocator Leo Yan
2016-02-26 3:43 ` Leo Yan
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20160303162942.GA2445@localhost.localdomain \
--to=edubezval-re5jqeeqqe8avxtiumwx3w@public.gmane.org \
--cc=Punit.Agrawal-5wv7dgnIgG8@public.gmane.org \
--cc=catalin.marinas-5wv7dgnIgG8@public.gmane.org \
--cc=devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
--cc=galak-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org \
--cc=ijc+devicetree-KcIKpvwj1kUDXYZnReoRVg@public.gmane.org \
--cc=javi.merino-5wv7dgnIgG8@public.gmane.org \
--cc=kong.kongxinwei-C8/M+/jPZTeaMJb+Lgu22Q@public.gmane.org \
--cc=leo.yan-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org \
--cc=linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org \
--cc=linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
--cc=linux-pm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
--cc=mark.rutland-5wv7dgnIgG8@public.gmane.org \
--cc=pawel.moll-5wv7dgnIgG8@public.gmane.org \
--cc=robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org \
--cc=rui.zhang-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org \
--cc=will.deacon-5wv7dgnIgG8@public.gmane.org \
--cc=xuwei5-C8/M+/jPZTeaMJb+Lgu22Q@public.gmane.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.