The size of unsigned long varies between 32 and 64 bit systems while
the size of phandle arguments is always 32 bits per parameter.
On 64-bit systems, cooling devices registered via of-thermal apis fail
to bind when the min/max cooling state is specified as
THERMAL_NO_LIMIT (-1UL) as there is a mis-match between the value read
from the device tree (32bit) and the pre-processor define (64bit).
As we're unlikely to need cooling states larger than 32 bits, and for
consistency with the size of phandle arguments, explicitly limit
THERMAL_NO_LIMIT to 32 bits.
Reported-by: Hyungwoo Yang <hwoo.yang@gmail.com>
Acked-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
This patch introduces a device tree bindings for
describing the hardware thermal behavior and limits.
Also a parser to read and interpret the data and feed
it in the thermal framework is presented.
This patch introduces a thermal data parser for device
tree. The parsed data is used to build thermal zones
and thermal binding parameters. The output data
can then be used to deploy thermal policies.
This patch adds also documentation regarding this
API and how to define tree nodes to use
this infrastructure.
Note that, in order to be able to have control
on the sensor registration on the DT thermal zone,
it was required to allow changing the thermal zone
.get_temp callback. For this reason, this patch
also removes the 'const' modifier from the .ops
field of thermal zone devices.
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
Punit Agrawal