The AD7768-1 provides a buffered common-mode voltage output
on the VCM pin that can be used to bias analog input signals.
Add adi,vcm-output to enable the configuration of the VCM output
circuit.
Signed-off-by: Jonathan Santos <Jonathan.Santos@xxxxxxxxxx>
---
v2 Changes:
* New patch in v2.
---
.../bindings/iio/adc/adi,ad7768-1.yaml | 10 ++++++++++
include/dt-bindings/iio/adc/adi,ad7768-1.h | 16 ++++++++++++++++
2 files changed, 26 insertions(+)
create mode 100644 include/dt-bindings/iio/adc/adi,ad7768-1.h
diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad7768-1.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad7768-1.yaml
index da05c8448530..e26513a9469b 100644
--- a/Documentation/devicetree/bindings/iio/adc/adi,ad7768-1.yaml
+++ b/Documentation/devicetree/bindings/iio/adc/adi,ad7768-1.yaml
@@ -59,6 +59,15 @@ properties:
In the absence of this property, Synchronization over SPI will be
enabled.
+ adi,vcm-output:
+ description: |
+ Configures the Common-Mode Voltage Output. The VCM is provided by an
+ amplifier external to the AD7768-1 and can be used as common-mode voltage
+ by the ADC. There are 8 output voltage options available, and the macros
+ for these values can be found at dt-bindings/iio/adi,ad7768-1.h
+ items:
+ enum: [0, 1, 2, 3, 4, 5, 6, 7]
+
reset-gpios:
maxItems: 1
@@ -132,6 +141,7 @@ examples:
gpio-controller;
#gpio-cells = <2>;
vref-supply = <&adc_vref>;
+ adi,vcm-output = <AD7768_VCM_OUTPUT_AVDD1_AVSS_2>;
interrupts = <25 IRQ_TYPE_EDGE_RISING>;
interrupt-parent = <&gpio>;
adi,sync-in-gpios = <&gpio 22 GPIO_ACTIVE_LOW>;
diff --git a/include/dt-bindings/iio/adc/adi,ad7768-1.h b/include/dt-bindings/iio/adc/adi,ad7768-1.h
new file mode 100644
index 000000000000..469ea724c0d5
--- /dev/null
+++ b/include/dt-bindings/iio/adc/adi,ad7768-1.h
@@ -0,0 +1,16 @@
+/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */
+
+#ifndef _DT_BINDINGS_ADI_AD7768_1_H
+#define _DT_BINDINGS_ADI_AD7768_1_H
+
+/* Sets VCM output to (AVDD1 − AVSS)/2 */
+#define AD7768_VCM_OUTPUT_AVDD1_AVSS_2 0x00
+#define AD7768_VCM_OUTPUT_2_5V 0x01
+#define AD7768_VCM_OUTPUT_2_05V 0x02
+#define AD7768_VCM_OUTPUT_1_9V 0x03
+#define AD7768_VCM_OUTPUT_1_65V 0x04
+#define AD7768_VCM_OUTPUT_1_1V 0x05
+#define AD7768_VCM_OUTPUT_0_9V 0x06
+#define AD7768_VCM_OUTPUT_OFF 0x07
+
+#endif /* _DT_BINDINGS_ADI_AD7768_1_H */
--
2.34.1
