On Tue, Feb 28, 2017 at 12:14:03PM -0800, Rick Altherr wrote:
> Signed-off-by: Rick Altherr <ralth...@google.com>
> ---
> .../devicetree/bindings/hwmon/aspeed_adc.txt | 48
> ++++++++++++++++++++++
ADCs should really be documented in one place regardless of whether
hwmon or IIO is used. Don't need to move it now, but certainly the
bindings need to be compatible.
> 1 file changed, 48 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/hwmon/aspeed_adc.txt
>
> diff --git a/Documentation/devicetree/bindings/hwmon/aspeed_adc.txt
> b/Documentation/devicetree/bindings/hwmon/aspeed_adc.txt
> new file mode 100644
> index 000000000000..9e481668c4d3
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/hwmon/aspeed_adc.txt
> @@ -0,0 +1,48 @@
> +Aspeed AST2400/2500 ADC
> +
> +This device is a 10-bit converter for 16 voltage channels. All inputs are
> +single ended. Each channel can be individually enabled to allow for use of
> +alternate pin functions.
> +
> +1) adc node
> +
> + Required properties:
> + - compatible : Should be one of
> + "aspeed,ast2400-adc"
> + "aspeed,ast2500-adc"
> + - reg : memory window mapping address and length
> + - #address-cells : must be <1> corresponding to the channel child binding
> + - #size-cells : must be <0> corresponding to the channel child binding
> + - clocks : Input clock used to derive the sample clock. Expected to be the
> + SoC's APB clock.
> + - update-interval-ms : initial time between updates on a channel
This is like sampling rate? I think we have a standard ADC property for
that.
> +
> + The node contains child nodes for each channel that the platform uses.
> +
> + Example adc node:
> + adc@1e6e9000 {
> + #address-cells = <1>;
> + #size-cells = <0>;
> + compatible = "aspeed,ast2400-adc";
> + reg = <0x1e6e9000 0xB0>;
> + clocks = <&clk_apb>;
> + update-interval-ms = <100>;
> +
> + [ child node definitions... ]
> + };
> +
> +2) channel nodes
> +
> + Optional properties:
> + - status: indicates the operational status of the device.
> + Value must be either "disabled" or "okay".
Don't need to document this.
> + - label : string describing the monitored value
You need a reg property for the channel number.
> +
> + Example channel node:
> + channel@1 {
> + status = "okay";
> + label = "3V3 rail";
> +
> + pinctrl-names = "default";
> + pinctrl-0 = <&pinctrl_adc0_default>;
Need to document these.
> + };
> --
> 2.11.0.483.g087da7b7c-goog
>
