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Message-ID: <a6b51de7-4f56-4db9-a7dd-60555ac6c37f@arm.com>
Date:   Thu, 12 Oct 2023 13:01:00 +0100
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Subject: Re: [PATCH 1/2] thermal/core: Hardening the self-encapsulation
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To:     Daniel Lezcano <daniel.lezcano@linaro.org>
Cc:     Thierry Reding <thierry.reding@gmail.com>, rafael@kernel.org,
        Amit Kucheria <amitk@kernel.org>,
        Zhang Rui <rui.zhang@intel.com>,
        "open list:THERMAL" <linux-pm@vger.kernel.org>,
        open list <linux-kernel@vger.kernel.org>
References: <20231012102700.2858952-1-daniel.lezcano@linaro.org>
From:   Lukasz Luba <lukasz.luba@arm.com>
In-Reply-To: <20231012102700.2858952-1-daniel.lezcano@linaro.org>
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Precedence: bulk

Hi Daniel,

On 10/12/23 11:26, Daniel Lezcano wrote:
> The thermal private header has leaked all around the drivers which
> interacted with the core internals. The thermal zone structure which
> was part of the exported header led also to a leakage of the fields
> into the different drivers, making very difficult to improve the core
> code without having to change the drivers.
> 
> Now we mostly fixed how the thermal drivers were interacting with the
> thermal zones (actually fixed how they should not interact). The
> thermal zone structure will be moved to the private thermal core
> header. This header has been removed from the different drivers and
> must belong to the core code only. In order to prevent this private
> header to be included again in the drivers, make explicit only the
> core code can include this header by defining a THERMAL_CORE_SUBSYS
> macro. The private header will contain a check against this macro.
> 
> The Tegra SoCtherm driver needs to access thermal_core.h to have the
> get_thermal_instance() function definition. It is the only one
> remaining driver which need to access the thermal_core.h header, so
> the check will emit a warning at compilation time.
> 
> Thierry Reding is reworking the driver to get rid of this function [1]
> and thus when the changes will be merged, the compilation warning will
> be converted to a compilation error, closing definitively the door to
> the drivers willing to play with the thermal zone device internals.

That looks like a good idea. Although, shouldn't we avoid the
compilation warnings and just first merge the fixes for drivers?

Regards,
Lukasz