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

Eugen Hristev
2017-12-22T15:07:10Z

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@microchip.com>
---
.../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 at 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 at 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 at 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.
+
For example:

device {
io-channels = <&adc 1>, <&ref 0>;
io-channel-names = "vcc", "vdd";
+ io-triggers = <&adc 0>, <&adc 1>;
+ io-trigger-names = "continuous", "external";
};

This represents a device with two IIO inputs, named "vcc" and "vdd".
The vcc channel is connected to output 1 of the &adc device, and the
vdd channel is connected to output 0 of the &ref device.
+The device also connects to two IIO trigger inputs, named "continuous" and
+"external". The continuous trigger is connected to the trigger output 0 of the
+&adc device, and the external trigger is connected to the trigger output 1 of
+the same &adc device.

==Example==

@@ -78,6 +120,7 @@ vdd channel is connected to output 0 of the &ref device.
compatible = "maxim,max1139";
reg = <0x35>;
#io-channel-cells = <1>;
+ #io-trigger-cells = <1>;
};

...
@@ -94,4 +137,11 @@ vdd channel is connected to output 0 of the &ref device.
compatible = "some-consumer";
io-channels = <&adc 10>, <&adc 11>;
io-channel-names = "adc1", "adc2";
+ io-triggers = <&adc 0>;
+ };
+
+ some_other_consumer {
+ compatible = "some-other-consumer";
+ io-triggers = <&adc 1>, <&adc 2>;
+ io-trigger-names = "edge-triggered", "pwm-generated";
};
--
2.7.4