Re: [PATCH RESEND] thermal: add generic cpufreq cooling implementation

["Rafael J. Wysocki" <rjw@sisk.pl>]

On Monday, September 10, 2012, Zhang Rui wrote:
> Refreshed to remove the notifier mechanism as we do not have a real user of it.
> if there is no problem, I'll apply the whole patch set to thermal next tree.
> 
> From: Amit Daniel Kachhap <amit.kachhap@linaro.org>
> Date: Thu, 16 Aug 2012 17:11:40 +0530
> 
> This patchset introduces a new generic cooling device based on cpufreq
> that can be used on non-ACPI platforms.  As a proof of concept, we have
> drivers for the following platforms using this mechanism now:
> 
>  * Samsung Exynos (Exynos4 and Exynos5) in the current patchset.
>  * Freescale i.MX (git://git.linaro.org/people/amitdanielk/linux.git imx6q_thermal)
> 
> There is a small change in cpufreq cooling registration APIs, so a minor
> change is needed for Freescale platforms.
> 
> Brief Description:
> 
> 1) The generic cooling devices code is placed inside driver/thermal/*
>    as placing inside acpi folder will need un-necessary enabling of acpi
>    code.  This code is architecture independent.
> 
> 2) This patchset adds generic cpu cooling low level implementation
>    through frequency clipping.  In future, other cpu related cooling
>    devices may be added here.  An ACPI version of this already exists
>    (drivers/acpi/processor_thermal.c) .But this will be useful for
>    platforms like ARM using the generic thermal interface along with the
>    generic cpu cooling devices.  The cooling device registration API's
>    return cooling device pointers which can be easily binded with the
>    thermal zone trip points.  The important APIs exposed are,
> 
>    a) struct thermal_cooling_device *cpufreq_cooling_register(
>         struct cpumask *clip_cpus)
>    b) void cpufreq_cooling_unregister(struct thermal_cooling_device *cdev)
> 
> 3) Samsung exynos platform thermal implementation is done using the
>    generic cpu cooling APIs and the new trip type.  The temperature sensor
>    driver present in the hwmon folder(registered as hwmon driver) is moved
>    to thermal folder and registered as a thermal driver.
> 
> A simple data/control flow diagrams is shown below,
> 
> Core Linux thermal <----->  Exynos thermal interface <----- Temperature Sensor
>           |                             |
>          \|/                            |
>   Cpufreq cooling device <---------------
> 
> TODO:
> *Will send the DT enablement patches later after the driver is merged.
> 
> This patch:
> 
> Add support for generic cpu thermal cooling low level implementations
> using frequency scaling up/down based on the registration parameters.
> Different cpu related cooling devices can be registered by the user and
> the binding of these cooling devices to the corresponding trip points can
> be easily done as the registration APIs return the cooling device pointer.
> The user of these APIs are responsible for passing clipping frequency .
> The drivers can also register to recieve notification about any cooling
> action called.
> 
> Cc: Guenter Roeck <guenter.roeck@ericsson.com>
> Cc: SangWook Ju <sw.ju@samsung.com>
> Cc: Durgadoss <durgadoss.r@intel.com>
> Cc: Len Brown <lenb@kernel.org>
> Cc: Jean Delvare <khali@linux-fr.org>
> Cc: Kyungmin Park <kmpark@infradead.org>
> Cc: Kukjin Kim <kgene.kim@samsung.com>
> Signed-off-by: Zhang Rui <rui.zhang@intel.com>
> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
> Signed-off-by: Amit Daniel Kachhap <amit.daniel@samsung.com>

Can you please resend the patch inline (i.e. not as an attachment)?

Rafael