Commit graph

2 commits

Author SHA1 Message Date
Sascha Hauer
17e8351a77 thermal: consistently use int for temperatures
The thermal code uses int, long and unsigned long for temperatures
in different places.

Using an unsigned type limits the thermal framework to positive
temperatures without need. Also several drivers currently will report
temperatures near UINT_MAX for temperatures below 0°C. This will probably
immediately shut the machine down due to overtemperature if started below
0°C.

'long' is 64bit on several architectures. This is not needed since INT_MAX °mC
is above the melting point of all known materials.

Consistently use a plain 'int' for temperatures throughout the thermal code and
the drivers. This only changes the places in the drivers where the temperature
is passed around as pointer, when drivers internally use another type this is
not changed.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>
Reviewed-by: Darren Hart <dvhart@linux.intel.com>
Reviewed-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Peter Feuerer <peter@piie.net>
Cc: Punit Agrawal <punit.agrawal@arm.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Eduardo Valentin <edubezval@gmail.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: Jean Delvare <jdelvare@suse.de>
Cc: Peter Feuerer <peter@piie.net>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Lukasz Majewski <l.majewski@samsung.com>
Cc: Stephen Warren <swarren@wwwdotorg.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: linux-acpi@vger.kernel.org
Cc: platform-driver-x86@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-omap@vger.kernel.org
Cc: linux-samsung-soc@vger.kernel.org
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Rafael J. Wysocki <rjw@rjwysocki.net>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: lm-sensors@lm-sensors.org
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
2015-08-03 23:15:50 +08:00
Ong, Boon Leong
8c18769396 thermal: intel Quark SoC X1000 DTS thermal driver
In Intel Quark SoC X1000, there is one on-die digital temperature sensor(DTS).
The DTS offers both hot & critical trip points.

However, in current distribution of UEFI BIOS for Quark platform, only
critical trip point is configured to be 105 degree Celsius (based on Quark
SW ver1.0.1 and hot trip point is not used due to lack of IRQ.

There is no active cooling device for Quark SoC, so Quark SoC thermal
management logic expects Linux distro to orderly power-off when temperature
of the DTS exceeds the configured critical trip point.

Kernel param "polling_delay" in milliseconds is used to control the frequency
the DTS temperature is read by thermal framework. It defaults to 2-second.
To change it, use kernel boot param "intel_quark_dts_thermal.polling_delay=X".

User interacts with Quark SoC DTS thermal driver through sysfs via:
/sys/class/thermal/thermal_zone0/

For example:
 - to read DTS temperature
   $ cat temp
 - to read critical trip point
   $ cat trip_point_0_temp
 - to read trip point type
   $ cat trip_point_0_type
 - to emulate temperature raise to test orderly shutdown by Linux distro
   $ echo 105 > emul_temp

Tested-by: Bryan O'Donoghue <pure.logic@nexus-software.ie>
Signed-off-by: Ong Boon Leong <boon.leong.ong@intel.com>
Reviewed-by: Bryan O'Donoghue <pure.logic@nexus-software.ie>
Reviewed-by: Kweh, Hock Leong <hock.leong.kweh@intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
2015-05-01 11:20:43 +08:00