apm821xx: add drivetemp sensor for the WD MyBook Series

This patch adds the hwmon-drivetemp to the device.
It also adds device-tree bindings. This can be useful to
automate external fans which can be controlled for example
by either an unused sata-port or by the usb-power regulator.

Signed-off-by: Christian Lamparter <[email protected]>

target/linux/apm821xx/dts/wd-mybooklive.dts

@@ -179,10 +179,20 @@
 
 &SATA0 {
 	status = "okay";
+
+	drive0: sata-port@0 {
+		reg = <0>;
+		#thermal-sensor-cells = <0>;
+	};
 };
 
 &SATA1 {
 	status = "okay";
+
+	drive1: sata-port@0 {
+		reg = <0>;
+		#thermal-sensor-cells = <0>;
+	};
 };
 
 &UART0 {

target/linux/apm821xx/sata/target.mk

@@ -1,6 +1,6 @@
 BOARDNAME := Devices which boot from SATA (NAS)
 FEATURES += ext4 usb ramdisk squashfs rootfs-part boot-part
-DEFAULT_PACKAGES += badblocks block-mount e2fsprogs \
+DEFAULT_PACKAGES += badblocks block-mount e2fsprogs kmod-hwmon-drivetemp \
 		    kmod-dm kmod-md-mod partx-utils mkf2fs f2fsck
 
 define Target/Description