ARM: dts: ux500: Add thermistors to the HREF

This adds the two temperature-monitoring thermistors to the
HREF reference design, defines a thermal zone for the
chassis and sets some reasonable thermal limits.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

arch/arm/boot/dts/ste-hrefv60plus.dtsi

@@ -10,6 +10,64 @@ / {
 	model = "ST-Ericsson HREF (v60+) platform with Device Tree";
 	compatible = "st-ericsson,hrefv60+", "st-ericsson,u8500";
 
+	thermal-zones {
+		chassis-thermal {
+			/* Poll every 20 seconds */
+			polling-delay = <20000>;
+			/* Poll every 2nd second when cooling */
+			polling-delay-passive = <2000>;
+
+			thermal-sensors = <&therm1>, <&therm2>;
+
+			/* Tripping points made from rough guess about operating conditions */
+			trips {
+				chassis_alert: chassis-alert {
+					/* At 50 degrees take down the CPU frequency */
+					temperature = <50000>;
+					hysteresis = <3000>;
+					type = "active";
+				};
+				chassis_crit: chassis-crit {
+					/* Just shut down at 70 degrees */
+					temperature = <70000>;
+					hysteresis = <2000>;
+					type = "critical";
+				};
+			};
+
+			/* Push down the operating frequency of the SoC when it gets hot */
+			cooling-maps {
+				map0 {
+					trip = <&chassis_alert>;
+					cooling-device = <&CPU0 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
+					contribution = <100>;
+				};
+			};
+		};
+	};
+
+	/*
+	 * Thermistors on the board, formally to monitor battery temperatures
+	 * but what they measure is the board temperature.
+	 */
+	therm1: thermistor@0 {
+		compatible = "murata,ncp18wb473";
+		io-channels = <&gpadc 0x06>; /* AUX1 */
+		pullup-uv = <1800000>;
+		pullup-ohm = <220000>;
+		pulldown-ohm = <0>;
+		#thermal-sensor-cells = <0>;
+	};
+
+	therm2: thermistor@1 {
+		compatible = "murata,ncp18wb473";
+		io-channels = <&gpadc 0x07>; /* AUX2 */
+		pullup-uv = <1800000>;
+		pullup-ohm = <220000>;
+		pulldown-ohm = <0>;
+		#thermal-sensor-cells = <0>;
+	};
+
 	soc {
 		/* Name the GPIO muxed rails on the HREF boards */
 		gpio@8012e000 {