Re: [PATCH 1/2] iio:as3935: Add DT binding docs for AS3935 driver

[Jonathan Cameron <jic23@kernel.org>]

On 06/02/14 07:00, Matt Ranostay wrote:
> Document compatible string, required and optional DT properties for
> AS3935 chipset driver.
>
> Signed-off-by: Matt Ranostay <mranostay@gmail.com>
> ---
>   .../devicetree/bindings/iio/proximity/as3935.txt   | 28 ++++++++++++++++++++++
>   .../devicetree/bindings/vendor-prefixes.txt        |  1 +
>   2 files changed, 29 insertions(+)
>   create mode 100644 Documentation/devicetree/bindings/iio/proximity/as3935.txt
>
> diff --git a/Documentation/devicetree/bindings/iio/proximity/as3935.txt b/Documentation/devicetree/bindings/iio/proximity/as3935.txt
> new file mode 100644
> index 0000000..574d49c
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/proximity/as3935.txt
> @@ -0,0 +1,28 @@
> +Austrian Microsystems AS3935 Franklin lightning sensor device driver
> +
> +Required properties:
> +	- compatible: must be "ams,as3935"
> +	- reg: SPI chip select number for the device
> +	- spi-cpha: SPI Mode 1. Refer to spi/spi-bus.txt for generic SPI
> +	slave node bindings.
> +	- interrupt-parent : should be the phandle for the interrupt controller
> +	- interrupts : interrupt mapping for GPIO IRQ
Why does it need to be a GPIO IRQ?  As far as I can see any irq will do
(note there are devices that provide suitable interrupts without the ability
to read the level).  Oops, we have a couple of other IIO bindings stating
exactly this.  I doubt they need to be GPIOs either.

> +
> +	Refer to interrupt-controller/interrupts.txt for generic
> +	interrupt client node bindings.
> +
> +Optional properties:
> +	- ams,tune-cap: Calibration tuning capacitor stepping value 0 - 15.
> +	  Range of 0 to 120 pF, 8pF steps. This will require using the
> +	  calibration data from the manufacturer.
Why not have this as the actual value rather than a magic number?  Might
as well keep the device tree as human readable as possible.
> +
> +Example:
> +
> +as3935@0 {
> +	compatible = "ams,as3935";
> +	reg = <0>;
> +	spi-cpha;
> +	interrupt-parent = <&gpio1>;
> +	interrupts = <16 1>;
> +	ams,tune-cap = <10>;
> +};
> diff --git a/Documentation/devicetree/bindings/vendor-prefixes.txt b/Documentation/devicetree/bindings/vendor-prefixes.txt
> index 3c31b40..9dd66ca 100644
> --- a/Documentation/devicetree/bindings/vendor-prefixes.txt
> +++ b/Documentation/devicetree/bindings/vendor-prefixes.txt
> @@ -10,6 +10,7 @@ aeroflexgaisler	Aeroflex Gaisler AB
>   ak	Asahi Kasei Corp.
>   altr	Altera Corp.
>   amcc	Applied Micro Circuits Corporation (APM, formally AMCC)
> +ams	AMS AG
>   amstaos	AMS-Taos Inc.
>   apm	Applied Micro Circuits Corporation (APM)
>   arm	ARM Ltd.
>