In addition to GPIO synchronization, The AD7768-1 also supports
synchronization over SPI, which use is recommended when the GPIO
cannot provide a pulse synchronous with the base MCLK signal. It
consists of looping back the SYNC_OUT to the SYNC_IN pin and send
a command via SPI to trigger the synchronization.
Add a new trigger-sources property to enable synchronization over SPI
and future multiple devices support. This property references the
main device (or trigger provider) responsible for generating the
SYNC_OUT pulse to drive the SYNC_IN of device.
While at it, add description to the interrupts property.
Signed-off-by: Jonathan Santos <Jonathan.Santos@xxxxxxxxxx>
---
v3 Changes:
* Fixed dt-bindings errors.
* Trigger-source is set as an alternative to sync-in-gpios, so we
don't break the previous ABI.
* increased maxItems from trigger-sources to 2.
v2 Changes:
* Patch added as replacement for adi,sync-in-spi patch.
* addressed the request for a description to interrupts property.
---
.../bindings/iio/adc/adi,ad7768-1.yaml | 28 +++++++++++++++++--
1 file changed, 25 insertions(+), 3 deletions(-)
diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad7768-1.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad7768-1.yaml
index 3ce59d4d065f..4bcc9e20fab9 100644
--- a/Documentation/devicetree/bindings/iio/adc/adi,ad7768-1.yaml
+++ b/Documentation/devicetree/bindings/iio/adc/adi,ad7768-1.yaml
@@ -26,7 +26,19 @@ properties:
clock-names:
const: mclk
+ trigger-sources:
+ description:
+ Specifies the device responsible for driving the synchronization pin,
+ as an alternative to adi,sync-in-gpios. If the own device node is
+ referenced, The synchronization over SPI is enabled and the SYNC_OUT
+ output will drive the SYNC_IN pin.
+ maxItems: 2
+
interrupts:
+ description:
+ Specifies the interrupt line associated with the ADC. This refers
+ to the DRDY (Data Ready) pin, which signals when conversion results are
+ available.
maxItems: 1
'#address-cells':
@@ -57,6 +69,9 @@ properties:
"#io-channel-cells":
const: 1
+ "#trigger-source-cells":
+ const: 0
+
required:
- compatible
- reg
@@ -65,7 +80,6 @@ required:
- vref-supply
- spi-cpol
- spi-cpha
- - adi,sync-in-gpios
patternProperties:
"^channel@([0-9]|1[0-5])$":
@@ -89,6 +103,13 @@ patternProperties:
allOf:
- $ref: /schemas/spi/spi-peripheral-props.yaml#
+ - oneOf:
+ - required:
+ - trigger-sources
+ - "#trigger-source-cells"
+ - required:
+ - adi,sync-in-gpios
+
unevaluatedProperties: false
examples:
@@ -99,7 +120,7 @@ examples:
#address-cells = <1>;
#size-cells = <0>;
- adc@0 {
+ adc0: adc@0 {
compatible = "adi,ad7768-1";
reg = <0>;
spi-max-frequency = <2000000>;
@@ -108,7 +129,8 @@ examples:
vref-supply = <&adc_vref>;
interrupts = <25 IRQ_TYPE_EDGE_RISING>;
interrupt-parent = <&gpio>;
- adi,sync-in-gpios = <&gpio 22 GPIO_ACTIVE_LOW>;
+ trigger-sources = <&adc0 0>;
+ #trigger-source-cells = <0>;
reset-gpios = <&gpio 27 GPIO_ACTIVE_LOW>;
clocks = <&ad7768_mclk>;
clock-names = "mclk";
--
2.34.1
