Date:   Thu, 16 Feb 2023 06:45:48 -0500
From:   Paul Gortmaker <paul.gortmaker@windriver.com>
To:     Hans de Goede <hdegoede@redhat.com>
Cc:     Daniel Lezcano <daniel.lezcano@linaro.org>,
        Peter Kaestle <peter@piie.net>,
        Mark Gross <markgross@kernel.org>,
        "open list:ACER ASPIRE ONE TEMPERATURE AND FAN DRIVER" 
        <platform-driver-x86@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: acerhdf thermal question
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[Re: acerhdf thermal question] On 16/02/2023 (Thu 10:08) Hans de Goede wrote:

> Hi Daniel,
> 
> On 2/16/23 09:57, Daniel Lezcano wrote:
> > 
> > Hi,
> > 
> > the polling interval is specified and modified via a kernel module parameter [1]
> > 
> > The value is used to change the polling interval of the thermal zone, implying that is accessing the thermal zone device structure internals directly [2]
> > 
> > In real use case, is the interval changed at runtime? Or just when the module is loaded? If the latter, the interval can be passed to the thermal zone at init time without doing a polling change rate after the thermal zone started. In this case, we can remove the polling_delay_jiffies change in the code and fix the structure leakage in this driver.
> 
> I believe this very likely only is used at module load-time.
> So the changes you suggest are fine with me.
> 
> I have added Paul Gortmaker to the Cc, Paul is the last person
> to have done any real (*) work on acerhfd AFAICT.
> 
> Paul any objections against making the acerhdf.interval parameter
> something which only works when set at boot / module load time
> and removing the ability to change it at runtime ?

Not that I have any real authority, beyond "touched it last", but
that aside, I'd say that if it is blocking other subsystem cleanups,
then by all means make it load-time only.

It was already obsolete hardware when I was tinkering with it, and
to my surprise -- that was already five years ago!  There can't be a
large user base out there - and even less tinkering with poll delay.

Paul.
--

> 
> Regards,
> 
> Hans
> 
> 
> *) Real as in not related to keeping it aligned with the thermal
> framework/core
> 
>