@@ -119,13 +119,11 @@
/*
* This is a Sunon Maglev GM0502PFV2-8 cooling fan @10000 RPM.
- * Since the platform has no temperature sensor, this is controlled
- * from userspace by using the hard disks S.M.A.R.T. temperature
* sensor. It is turned on when the temperature exceeds 46 degrees
* and turned off when the temperatures goes below 41 degrees
* (celsius).
*/
- gpio-fan {
+ fan0: gpio-fan {
compatible = "gpio-fan";
/* Collides with IDE */
gpios = <&gpio1 6 GPIO_ACTIVE_HIGH>;
@@ -133,6 +131,40 @@
#cooling-cells = <2>;
};
+ thermal-zones {
+ chassis-thermal {
+ /* Poll every 20 seconds */
+ polling-delay = <20000>;
+ /* Poll every 2nd second when cooling */
+ polling-delay-passive = <2000>;
+ /* Use the thermal sensor in the hard drive */
+ thermal-sensors = <&drive0>;
+
+ /* Tripping points from the fan.script in the rootfs */
+ trips {
+ alert: chassis-alert {
+ /* At 43 degrees turn on the fan */
+ temperature = <43000>;
+ hysteresis = <3000>;
+ type = "active";
+ };
+ crit: chassis-crit {
+ /* Just shut down at 60 degrees */
+ temperature = <60000>;
+ hysteresis = <2000>;
+ type = "critical";
+ };
+ };
+
+ cooling-maps {
+ map0 {
+ trip = <&alert>;
+ cooling-device = <&fan0 1 1>;
+ };
+ };
+ };
+ };
+
/*
* The touchpad input is connected to a GPIO bit-banged
* I2C bus.
@@ -445,6 +477,16 @@
ide@63000000 {
status = "okay";
+
+ /*
+ * This drive may have a temperature sensor with a
+ * thermal zone we can use for thermal control of the
+ * chassis temperature using the fan.
+ */
+ drive0: ide-port@0 {
+ reg = <0>;
+ #thermal-sensor-cells = <0>;
+ };
};
display-controller@6a000000 {
The DIR-685 can now exploit the thermal zone added by the drive temperature sensor inside the hard drive. We have patched the libata subsystem to assign the device nodes properly to the SCSI devices and this is what the drivetemp driver will use to populate the sensor and the thermal zone, so pick that up into the thermal zone and let this control the fan. The hardware lacks an embedded temperature sensor so the D-Link vendor firmware uses this method to control the temperature of the NAS enclosure using the thermal sensor inside the hard drive. The drive temperature trigger points to be used comes from the vendor firmware. Signed-off-by: Linus Walleij <linus.walleij@linaro.org> --- arch/arm/boot/dts/gemini-dlink-dir-685.dts | 48 ++++++++++++++++++++-- 1 file changed, 45 insertions(+), 3 deletions(-)