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3 commits

Author SHA1 Message Date
Matthew Wilcox
7a6639dca6 thermal: convert clock cooling to use an IDA
thermal clock cooling does not use the ability to look up pointers by ID,
so convert it from using an IDR to the more space-efficient IDA.

Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
2017-01-04 12:47:28 +08:00
Wei Yongjun
165989a5b6 thermal: clock_cooling: Fix missing mutex_init()
The driver allocates the mutex but not initialize it.
Use mutex_init() on it to initialize it correctly.

This is detected by Coccinelle semantic patch.

Signed-off-by: Wei Yongjun <weiyj.lk@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
2016-08-08 10:57:39 +08:00
Eduardo Valentin
f9df89d897 thermal: introduce clock cooling device
This patch introduces a new thermal cooling device based on common clock
framework. The original motivation to write this cooling device is to be
able to cool down thermal zones using clocks that feed co-processors, such
as GPUs, DSPs, Image Processing Co-processors, etc. But it is written
in a way that it can be used on top of any clock.

The implementation is pretty straight forward. The code creates
a thermal cooling device based on a pair of a struct device and a clock name.
The struct device is assumed to be usable by the OPP layer. The OPP layer
is used as source of the list of possible frequencies. The (cpufreq) frequency
table is then used as a map from frequencies to cooling states. Cooling
states are indexes to the frequency table.

The logic sits on top of common clock framework, specifically on clock
pre notifications. Any PRE_RATE_CHANGE is hijacked, and the transition is
only allowed when the new rate is within the thermal limit (cooling state -> freq).

When a thermal cooling device state transition is requested, the clock
is also checked to verify if the current clock rate is within the new
thermal limit.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Mike Turquette <mturquette@linaro.org>
Cc: Nishanth Menon <nm@ti.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Len Brown <len.brown@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-pm@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
2014-11-20 10:43:16 -04:00