Thermal: Add ST-Ericsson DB8500 thermal driver.

This driver is based on the thermal management framework in thermal_sys.c. A
thermal zone device is created with the trip points to which cooling devices
can be bound, the current cooling device is cpufreq, e.g. CPU frequency is
clipped down to cool the CPU, and other cooling devices can be added and bound
to the trip points dynamically.  The platform specific PRCMU interrupts are
used to active thermal update when trip points are reached.

Signed-off-by: hongbo.zhang <hongbo.zhang@linaro.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Francesco Lavra <francescolavra.fl@gmail.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>

1 files changed, 44 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/thermal/db8500-thermal.txt b/Documentation/devicetree/bindings/thermal/db8500-thermal.txt
new file mode 100644
index 000000000000..2e1c06fad81f
--- /dev/null
+++ b/Documentation/devicetree/bindings/thermal/db8500-thermal.txt
@@ -0,0 +1,44 @@
+* ST-Ericsson DB8500 Thermal
+
+** Thermal node properties:
+
+- compatible : "stericsson,db8500-thermal";
+- reg : address range of the thermal sensor registers;
+- interrupts : interrupts generated from PRCMU;
+- interrupt-names : "IRQ_HOTMON_LOW" and "IRQ_HOTMON_HIGH";
+- num-trips : number of total trip points, this is required, set it 0 if none,
+  if greater than 0, the following properties must be defined;
+- tripN-temp : temperature of trip point N, should be in ascending order;
+- tripN-type : type of trip point N, should be one of "active" "passive" "hot"
+  "critical";
+- tripN-cdev-num : number of the cooling devices which can be bound to trip
+  point N, this is required if trip point N is defined, set it 0 if none,
+  otherwise the following cooling device names must be defined;
+- tripN-cdev-nameM : name of the No. M cooling device of trip point N;
+
+Usually the num-trips and tripN-*** are separated in board related dts files.
+
+Example:
+thermal@801573c0 {
+	compatible = "stericsson,db8500-thermal";
+	reg = <0x801573c0 0x40>;
+	interrupts = <21 0x4>, <22 0x4>;
+	interrupt-names = "IRQ_HOTMON_LOW", "IRQ_HOTMON_HIGH";
+
+	num-trips = <3>;
+
+	trip0-temp = <75000>;
+	trip0-type = "active";
+	trip0-cdev-num = <1>;
+	trip0-cdev-name0 = "thermal-cpufreq-0";
+
+	trip1-temp = <80000>;
+	trip1-type = "active";
+	trip1-cdev-num = <2>;
+	trip1-cdev-name0 = "thermal-cpufreq-0";
+	trip1-cdev-name1 = "thermal-fan";
+
+	trip2-temp = <85000>;
+	trip2-type = "critical";
+	trip2-cdev-num = <0>;
+}