RE: [PATCH V7 1/4] dt-bindings: fsl: scu: add thermal binding

[Aisheng Dong <aisheng.dong@nxp.com>]

> From: Anson Huang
> Sent: Wednesday, February 20, 2019 2:54 PM
> 
> NXP i.MX8QXP is an ARMv8 SoC with a Cortex-M4 core inside as system
> controller, the system controller is in charge of system power, clock and
> thermal sensors etc. management, Linux kernel has to communicate with
> system controller via MU (message unit) IPC to get temperature from thermal
> sensors, this patch adds binding doc for i.MX system controller thermal driver.
> 
> Signed-off-by: Anson Huang <Anson.Huang@nxp.com>
> Reviewed-by: Rob Herring <robh@kernel.org>
> ---
> Changes since V6:
> 	- put "imx,sensor-resource-id" property in thermal zone nodes.
> ---
>  .../devicetree/bindings/arm/freescale/fsl,scu.txt  | 27
> ++++++++++++++++++++++
>  1 file changed, 27 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> index 72d481c..ad96881 100644
> --- a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> +++ b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> @@ -122,6 +122,27 @@ RTC bindings based on SCU Message Protocol
> Required properties:
>  - compatible: should be "fsl,imx8qxp-sc-rtc";
> 
> +Thermal bindings based on SCU Message Protocol
> +------------------------------------------------------------
> +
> +Required properties:
> +- compatible : Must be "fsl,imx-sc-thermal";
> +- tsens-num : Total number of thermal sensors supported;

We properly don't need this property if the number of sensor
is fixed on a specific SoC.

> +- #thermal-sensor-cells : Should be 1. See
> +			  Documentation/devicetree/bindings/thermal/thermal.txt
> +			  for a description.
> +
> +Required properties for thermal zone nodes:
> +- imx,sensor-resource-id : This property should be defined in each thermal

After a further looking at it, I wonder this property may not needed either.

> zone
> +			   of thermal-zones node, it passes each thermal zone's
> +			   resource id for thermal driver to get temperature via
> +			   SCU IPC.
> +
> +			   For thermal zone nodes, please refer to below binding
> +			   doc for details:
> +
> +[1] Documentation/devicetree/bindings/thermal/thermal.txt
> +
>  Example (imx8qxp):
>  -------------
>  lsio_mu1: mailbox@5d1c0000 {
> @@ -168,6 +189,12 @@ firmware {
>  		rtc: rtc {
>  			compatible = "fsl,imx8qxp-sc-rtc";
>  		};
> +
> +		tsens: thermal-sensor {
> +			compatible = "fsl,imx8qxp-sc-thermal";
> +			tsens-num = <1>;
> +			#thermal-sensor-cells = <1>;

This looks may not correct if sensor cells is 1 but the sensor number
Is also 1.
So we probably better remove tsens-num property.

Regards
Dong Aisheng

> +		};
>  	};
>  };
> 
> --
> 2.7.4