Re: [PATCH 03/14] dt-bindings: iio: add binding support for iio trigger provider/consumer

From: Rob Herring
Date: Tue Dec 26 2017 - 17:35:11 EST


On Fri, Dec 22, 2017 at 05:07:10PM +0200, Eugen Hristev wrote:
> Add bindings for producer/consumer for iio triggers.
>
> Similar with iio channels, the iio triggers can be connected between drivers:
> one driver will be a producer by registering iio triggers, and another driver
> will connect as a consumer.
>
> Signed-off-by: Eugen Hristev <eugen.hristev@xxxxxxxxxxxxx>
> ---
> .../devicetree/bindings/iio/iio-bindings.txt | 52 +++++++++++++++++++++-
> 1 file changed, 51 insertions(+), 1 deletion(-)
>
> diff --git a/Documentation/devicetree/bindings/iio/iio-bindings.txt b/Documentation/devicetree/bindings/iio/iio-bindings.txt
> index 68d6f8c..d861f0df 100644
> --- a/Documentation/devicetree/bindings/iio/iio-bindings.txt
> +++ b/Documentation/devicetree/bindings/iio/iio-bindings.txt
> @@ -11,6 +11,10 @@ value of a #io-channel-cells property in the IIO provider node.
>
> [1] http://marc.info/?l=linux-iio&m=135902119507483&w=2
>
> +Moreover, the provider can have a set of triggers that can be attached to
> +from the consumer drivers.
> +
> +
> ==IIO providers==
>
> Required properties:
> @@ -18,6 +22,11 @@ Required properties:
> with a single IIO output and 1 for nodes with multiple
> IIO outputs.
>
> +Optional properties:
> +#io-trigger-cells: Number of cells for the IIO trigger specifier. Typically 0
> + for nodes with a single IIO trigger and 1 for nodes with
> + multiple IIO triggers.
> +
> Example for a simple configuration with no trigger:
>
> adc: voltage-sensor@35 {
> @@ -26,7 +35,7 @@ Example for a simple configuration with no trigger:
> #io-channel-cells = <1>;
> };
>
> -Example for a configuration with trigger:
> +Example for a configuration with channels provided by trigger:
>
> adc@35 {
> compatible = "some-vendor,some-adc";
> @@ -42,6 +51,17 @@ Example for a configuration with trigger:
> };
> };
>
> +Example for a configuration for a trigger provider:
> +
> + adc: sensor-with-trigger@35 {
> + compatible = "some-vendor,some-adc";
> + reg = <0x35>;
> + #io-channel-cells = <1>;
> + #io-trigger-cells = <1>;
> + /* other properties */
> + };
> +
> +
> ==IIO consumers==
>
> Required properties:
> @@ -61,16 +81,38 @@ io-channel-ranges:
> IIO channels from this node. Useful for bus nodes to provide
> and IIO channel to their children.
>
> +io-triggers: List of phandle and IIO specifier pairs, one pair
> + for each trigger input to the device. Note: if the
> + IIO trigger provider specifies '0' for #io-trigger-cells,
> + then only the phandle portion of the pair will appear.
> +
> +io-trigger-names:
> + List of IIO trigger input name strings sorted in the same
> + order as the io-triggers property. Consumers drivers
> + will use io-trigger-names to match IIO trigger input names
> + with IIO specifiers.
> +
> +io-trigger-ranges:
> + Empty property indicating that child nodes can inherit named
> + IIO triggers from this node. Useful for bus nodes to provide
> + IIO triggers to their children.

I think it would be better to be explicit in the child nodes. What's the
use you had in mind?

Rob