On Thu, 20 Oct 2016, Peter Rosin wrote:
nitpicking below
> Signed-off-by: Peter Rosin <p...@axentia.se>
> ---
> .../bindings/iio/adc/envelope-detector.txt | 65
> ++++++++++++++++++++++
> MAINTAINERS | 6 ++
> 2 files changed, 71 insertions(+)
> create mode 100644
> Documentation/devicetree/bindings/iio/adc/envelope-detector.txt
>
> diff --git a/Documentation/devicetree/bindings/iio/adc/envelope-detector.txt
> b/Documentation/devicetree/bindings/iio/adc/envelope-detector.txt
> new file mode 100644
> index 000000000000..0e26299516fd
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/adc/envelope-detector.txt
> @@ -0,0 +1,65 @@
> +Bindings for ADC envelope detector using a DAC and a comparator
> +
> +The DAC is used to find the peak level of an alternating voltage input
> +signal by a binary search using the output of a comparator wired to
> +an interrupt pin. Like so:
> + _
> + | \
> + input +------>-------|+ \
> + | \
> + .-------. | }---.
> + | | | / |
> + | dac|-->--|- / |
> + | | |_/ |
> + | | |
> + | | |
> + | irq|------<-------'
> + | |
> + '-------'
> +
> +Required properties:
> +- compatible: Should be "envelope-detector"
> +- io-channels: Channel node of the dac to be used for comparator input.
> +- io-channel-names: Should be "dac".
> +- interrupt specification for one client interrupt,
> + see ../../interrupt-controller/interrupts.txt for details.
> +- interrupt-names: Should be "comp".
> +- envelope-detector,dac-max: The maximum raw input value for the dac.
> +- envelope-detector,comp-interval-ms: How long to wait for the comparator
> + to trigger before moving on to another DAC level. This interval needs to
> + relate to the lowest possible frequency of the above input signal.
> +
> +Optional properties:
> +- envelope-detector,inverted: If the input signal is centered around the
> + dac-max voltage (instead of zero), this property causes the detector to
> + search for the lowest DAC value that does not triggers the comparator
does not trigger
> + (instead of the highest). The result is also inverted so that a lower DAC
> + reading yields a higher voltage value.
> +
> +
> +Example:
> +
> + &spi {
> + dac: ad7303@4 {
> + compatible = "adi,ad7303";
> + reg = <4>;
> + spi-max-frequency = <10000000>;
> + Vdd-supply = <&vdd_supply>;
> + adi,use-external-reference;
> + REF-supply = <&vref_supply>;
> + #io-channel-cells = <1>;
> + };
> + };
> +
> + envelope-detector {
> + compatible = "envelope-detector";
> + io-channels = <&dac 0>;
> + io-channel-names = "dac";
> +
> + interrupt-parent = <&gpio>;
> + interrupts = <3 IRQ_TYPE_EDGE_FALLING>;
> + interrupt-names = "comp";
> +
> + envelope-detector,dac-max = <255>;
> + envelope-detector,comp-interval-ms = <50>;
> + };
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 8c8aae24b96b..4b6f6ec1b703 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -6118,6 +6118,12 @@ S: Maintained
> F: Documentation/devicetree/bindings/iio/dac/dpot-dac.txt
> F: drivers/iio/dac/dpot-dac.c
>
> +IIO ENVELOPE DETECTOR
> +M: Peter Rosin <p...@axentia.se>
> +L: linux-...@vger.kernel.org
> +S: Maintained
> +F: Documentation/devicetree/bindings/iio/adc/envelope-detector.txt
> +
> IIO SUBSYSTEM AND DRIVERS
> M: Jonathan Cameron <ji...@kernel.org>
> R: Hartmut Knaack <knaac...@gmx.de>
>
--
Peter Meerwald-Stadler
+43-664-2444418 (mobile)
