[PATCH v4 1/3] dt-bindings: iio: adc: add AD4695 and similar ADCs
From: David Lechner
Date: Thu Jul 11 2024 - 15:16:12 EST
Add device tree bindings for AD4695 and similar ADCs.
Reviewed-by: Conor Dooley <conor.dooley@xxxxxxxxxxxxx>
Signed-off-by: David Lechner <dlechner@xxxxxxxxxxxx>
---
Note, this may trigger a DT build warning "common-mode-channel: missing
type definition" if the builder doesn't include the recently added
common-mode-channel property [1]. This should be safe to ignore (passes
make dt_binding_check locally).
[1] https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio.git/commit/?h=testing&id=d86deaec1c5b0fb60c3619e8d2ae7a1d722fd2ad
v4 changes:
* Picked up Conor's reviewed-by tag.
v3 changes:
* Change interrupts to be per pin instead of per signal.
* Drop diff-channels and single-channel properties.
* Odd numbered pins added to common-mode-channel property enum.
* REFGND and COM values changes to avoid confusion with pin numbers.
* Add inX-supply properties for odd numbed input pins.
v2 changes:
* Drop *-wlcsp compatible strings
* Don't use fallback compatible strings
* Reword supply descriptions
* Use standard channel properties instead of adi,pin-pairing
* Fix unnecessary | character
* Fix missing blank line
* Add header file with common mode channel macros
---
.../devicetree/bindings/iio/adc/adi,ad4695.yaml | 256 +++++++++++++++++++++
MAINTAINERS | 10 +
include/dt-bindings/iio/adi,ad4695.h | 9 +
3 files changed, 275 insertions(+)
diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad4695.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad4695.yaml
new file mode 100644
index 000000000000..a2e824e26691
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/adc/adi,ad4695.yaml
@@ -0,0 +1,256 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/adc/adi,ad4695.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Analog Devices Easy Drive Multiplexed SAR Analog to Digital Converters
+
+maintainers:
+ - Michael Hennerich <Michael.Hennerich@xxxxxxxxxx>
+ - Nuno Sá <nuno.sa@xxxxxxxxxx>
+
+description: |
+ A family of similar multi-channel analog to digital converters with SPI bus.
+
+ * https://www.analog.com/en/products/ad4695.html
+ * https://www.analog.com/en/products/ad4696.html
+ * https://www.analog.com/en/products/ad4697.html
+ * https://www.analog.com/en/products/ad4698.html
+
+$ref: /schemas/spi/spi-peripheral-props.yaml#
+
+properties:
+ compatible:
+ enum:
+ - adi,ad4695
+ - adi,ad4696
+ - adi,ad4697
+ - adi,ad4698
+
+ reg:
+ maxItems: 1
+
+ spi-max-frequency:
+ maximum: 80000000
+
+ spi-cpol: true
+ spi-cpha: true
+
+ spi-rx-bus-width:
+ minimum: 1
+ maximum: 4
+
+ avdd-supply:
+ description: Analog power supply.
+
+ vio-supply:
+ description: I/O pin power supply.
+
+ ldo-in-supply:
+ description: Internal LDO Input. Mutually exclusive with vdd-supply.
+
+ vdd-supply:
+ description: Core power supply. Mutually exclusive with ldo-in-supply.
+
+ ref-supply:
+ description:
+ External reference voltage. Mutually exclusive with refin-supply.
+
+ refin-supply:
+ description:
+ Internal reference buffer input. Mutually exclusive with ref-supply.
+
+ com-supply:
+ description: Common voltage supply for pseudo-differential analog inputs.
+
+ adi,no-ref-current-limit:
+ $ref: /schemas/types.yaml#/definitions/flag
+ description:
+ When this flag is present, the REF Overvoltage Reduced Current protection
+ is disabled.
+
+ adi,no-ref-high-z:
+ $ref: /schemas/types.yaml#/definitions/flag
+ description:
+ Enable this flag if the ref-supply requires Reference Input High-Z Mode
+ to be disabled for proper operation.
+
+ cnv-gpios:
+ description: The Convert Input (CNV). If omitted, CNV is tied to SPI CS.
+ maxItems: 1
+
+ reset-gpios:
+ description: The Reset Input (RESET). Should be configured GPIO_ACTIVE_LOW.
+ maxItems: 1
+
+ interrupts:
+ minItems: 1
+ items:
+ - description: Signal coming from the BSY_ALT_GP0 pin (ALERT or BUSY).
+ - description: Signal coming from the GP2 pin (ALERT).
+ - description: Signal coming from the GP3 pin (BUSY).
+
+ interrupt-names:
+ minItems: 1
+ items:
+ - const: gp0
+ - const: gp2
+ - const: gp3
+
+ gpio-controller: true
+
+ "#gpio-cells":
+ const: 2
+ description: |
+ The first cell is the GPn number: 0 to 3.
+ The second cell takes standard GPIO flags.
+
+ "#address-cells":
+ const: 1
+
+ "#size-cells":
+ const: 0
+
+patternProperties:
+ "^in(?:[13579]|1[135])-supply$":
+ description:
+ Optional voltage supply for odd numbered channels when they are used as
+ the negative input for a pseudo-differential channel.
+
+ "^channel@[0-9a-f]$":
+ type: object
+ $ref: adc.yaml
+ unevaluatedProperties: false
+ description:
+ Describes each individual channel. In addition the properties defined
+ below, bipolar from adc.yaml is also supported.
+
+ properties:
+ reg:
+ maximum: 15
+
+ common-mode-channel:
+ description:
+ Describes the common mode channel for single channels. 0xFF is REFGND
+ and OxFE is COM. Macros are available for these values in
+ dt-bindings/iio/adi,ad4695.h. Values 1 to 15 correspond to INx inputs.
+ Only odd numbered INx inputs can be used as common mode channels.
+ items:
+ enum: [1, 3, 5, 7, 9, 11, 13, 15, 0xFE, 0xFF]
+ default: 0xFF
+
+ adi,no-high-z:
+ $ref: /schemas/types.yaml#/definitions/flag
+ description:
+ Enable this flag if the input pin requires the Analog Input High-Z
+ Mode to be disabled for proper operation.
+
+ required:
+ - reg
+
+ allOf:
+ # bipolar mode can't be used with REFGND
+ - if:
+ properties:
+ common-mode-channel:
+ const: 0xFF
+ then:
+ properties:
+ bipolar: false
+
+required:
+ - compatible
+ - reg
+ - avdd-supply
+ - vio-supply
+
+allOf:
+ - oneOf:
+ - required:
+ - ldo-in-supply
+ - required:
+ - vdd-supply
+
+ - oneOf:
+ - required:
+ - ref-supply
+ - required:
+ - refin-supply
+
+ # the internal reference buffer always requires high-z mode
+ - if:
+ required:
+ - refin-supply
+ then:
+ properties:
+ adi,no-ref-high-z: false
+
+ # limit channels for 8-channel chips
+ - if:
+ properties:
+ compatible:
+ contains:
+ enum:
+ - adi,ad4697
+ - adi,ad4698
+ then:
+ patternProperties:
+ "^in(?:9|1[135])-supply$": false
+ "^channel@[0-7]$":
+ properties:
+ reg:
+ maximum: 7
+ common-mode-channel:
+ items:
+ enum: [1, 3, 5, 7, 0xFE, 0xFF]
+ "^channel@[8-9a-f]$": false
+
+unevaluatedProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/gpio/gpio.h>
+ #include <dt-bindings/iio/adi,ad4695.h>
+
+ spi {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ adc@0 {
+ compatible = "adi,ad4695";
+ reg = <0>;
+ spi-cpol;
+ spi-cpha;
+ spi-max-frequency = <80000000>;
+ avdd-supply = <&power_supply>;
+ ldo-in-supply = <&power_supply>;
+ vio-supply = <&io_supply>;
+ refin-supply = <&supply_5V>;
+ com-supply = <&supply_2V5>;
+ in3-supply = <&supply_2V5>;
+ reset-gpios = <&gpio 1 GPIO_ACTIVE_LOW>;
+
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ /* Pseudo-differential channel between IN0 and REFGND. */
+ channel@0 {
+ reg = <0>;
+ };
+
+ /* Pseudo-differential channel between IN1 and COM. */
+ channel@1 {
+ reg = <1>;
+ common-mode-channel = <AD4695_COMMON_MODE_COM>;
+ bipolar;
+ };
+
+ /* Pseudo-differential channel between IN2 and IN3. */
+ channel@2 {
+ reg = <2>;
+ common-mode-channel = <3>;
+ bipolar;
+ };
+ };
+ };
diff --git a/MAINTAINERS b/MAINTAINERS
index 06ecfa64a39a..4aea2efd307d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1208,6 +1208,16 @@ F: Documentation/ABI/testing/sysfs-bus-iio-adc-ad4130
F: Documentation/devicetree/bindings/iio/adc/adi,ad4130.yaml
F: drivers/iio/adc/ad4130.c
+ANALOG DEVICES INC AD4695 DRIVER
+M: Michael Hennerich <michael.hennerich@xxxxxxxxxx>
+M: Nuno Sá <nuno.sa@xxxxxxxxxx>
+R: David Lechner <dlechner@xxxxxxxxxxxx>
+L: linux-iio@xxxxxxxxxxxxxxx
+S: Supported
+W: https://ez.analog.com/linux-software-drivers
+F: Documentation/devicetree/bindings/iio/adc/adi,ad4695.yaml
+F: include/dt-bindings/iio/adi,ad4695.h
+
ANALOG DEVICES INC AD7091R DRIVER
M: Marcelo Schmitt <marcelo.schmitt@xxxxxxxxxx>
L: linux-iio@xxxxxxxxxxxxxxx
diff --git a/include/dt-bindings/iio/adi,ad4695.h b/include/dt-bindings/iio/adi,ad4695.h
new file mode 100644
index 000000000000..9fbef542bf67
--- /dev/null
+++ b/include/dt-bindings/iio/adi,ad4695.h
@@ -0,0 +1,9 @@
+/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */
+
+#ifndef _DT_BINDINGS_ADI_AD4695_H
+#define _DT_BINDINGS_ADI_AD4695_H
+
+#define AD4695_COMMON_MODE_REFGND 0xFF
+#define AD4695_COMMON_MODE_COM 0xFE
+
+#endif /* _DT_BINDINGS_ADI_AD4695_H */
--
2.43.0