Re: [PATCH v5 2/4] dt-bindings: thermal: nvme: Add binding documentation

[Rob Herring <robh@kernel.org>]

On Mon, Jul 01, 2019 at 11:12:32PM +0900, Akinobu Mita wrote:
> Add thermal binding documentation for NVMe temperature sensor.
> 
> Cc: Rob Herring <robh@kernel.org>
> Cc: Zhang Rui <rui.zhang@intel.com>
> Cc: Eduardo Valentin <edubezval@gmail.com>
> Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
> Cc: Keith Busch <kbusch@kernel.org>
> Cc: Jens Axboe <axboe@fb.com>
> Cc: Christoph Hellwig <hch@lst.de>
> Cc: Sagi Grimberg <sagi@grimberg.me>
> Cc: Minwoo Im <minwoo.im.dev@gmail.com>
> Cc: Kenneth Heitke <kenneth.heitke@intel.com>
> Cc: Chaitanya Kulkarni <Chaitanya.Kulkarni@wdc.com>
> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
> ---
> * v5
> - New patch
> 
>  Documentation/devicetree/bindings/thermal/nvme.txt | 56 ++++++++++++++++++++++
>  1 file changed, 56 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/thermal/nvme.txt
> 
> diff --git a/Documentation/devicetree/bindings/thermal/nvme.txt b/Documentation/devicetree/bindings/thermal/nvme.txt
> new file mode 100644
> index 0000000..60b90de
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/thermal/nvme.txt
> @@ -0,0 +1,56 @@
> +Binding for NVMe temperature sensor
> +
> +An NVMe controller reports up to nine temperature values in the SMART / Health
> +log.
> +
> +Required properties:
> +- reg: A five-cell address encoded as (phys.hi phys.mid phys.lo size.hi
> +  size.lo). phys.hi should contain the device's BDF (Bus/Device/Function)
> +  as 0b00000000 bbbbbbbb dddddfff 00000000. The other cells should be zero.
> +  See also Documentation/devicetree/bindings/pci/pci.txt
> +
> +- #thermal-sensor-cells: Must be 1. See ./thermal.txt for a description.
> +  In the thermal-sensors property, the sensor ID 0 for composite temperature,
> +  1 through 8 for NVMe temperature sensor N.
> +
> +Example:
> +
> +&pcie0 {
> +	...
> +	nvme: nvme@0,0 {
> +		reg = <0x0000 0 0 0 0>;
> +		#address-cells = <3>;
> +		#size-cells = <2>;
> +
> +		nvmetemp: nvmetemp {
> +			reg = <0x0000 0 0 0 0>; /* DEVFN = 0x00 (0:0) */

I'm not sure this is really valid PCI addressing as the parent has the 
same address.

> +			#thermal-sensor-cells = <1>;

Can't you just put this in the parent? Is this really a separate 
addressable device from the parent?

> +		};
> +	};
> +};
> +
> +&thermal_zones {
> +	nvme_thermal: nvme {
> +		polling-delay-passive = <2000>; /* milliseconds */
> +		polling-delay = <0>; /* asynchronous event driven */
> +
> +				/* sensor	ID */
> +		thermal-sensors = <&nvmetemp	0>;
> +
> +		trips {
> +			nvme_alert0: nvme_alert0 {
> +				temperature = <80000>; /* millicelsius */
> +				hysteresis = <2000>; /* millicelsius */
> +				type = "passive";
> +			};
> +		};
> +
> +		cooling-maps {
> +			map0 {
> +				trip = <&nvme_alert0>;
> +				cooling-device =
> +				<&fan0 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
> +			};
> +		};
> +	};
> +};
> -- 
> 2.7.4
>