thermal: imx: add necessary clk operation

Thermal sensor needs pll3_usb_otg when measuring temperature,
otherwise the temperature read will be incorrect, so need to
enable this clk before sensor working, for alarm function,
as hardware will take measurement periodically, so we should
keep this clk always on once alarm function is enabled.

Signed-off-by: Anson Huang <b20788@freescale.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/thermal/imx-thermal.txt b/Documentation/devicetree/bindings/thermal/imx-thermal.txt
index 541c25e49abf..1f0f67234a91 100644
--- a/Documentation/devicetree/bindings/thermal/imx-thermal.txt
+++ b/Documentation/devicetree/bindings/thermal/imx-thermal.txt
@@ -8,10 +8,14 @@ Required properties:
   calibration data, e.g. OCOTP on imx6q.  The details about calibration data
   can be found in SoC Reference Manual.
 
+Optional properties:
+- clocks : thermal sensor's clock source.
+
 Example:
 
 tempmon {
 	compatible = "fsl,imx6q-tempmon";
 	fsl,tempmon = <&anatop>;
 	fsl,tempmon-data = <&ocotp>;
+	clocks = <&clks 172>;
 };