Add device tree documentation for AD4000 series of ADC devices.
Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ad4000-4004-4008.pdf
Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ad4001-4005.pdf
Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ad4002-4006-4010.pdf
Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ad4003-4007-4011.pdf
Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ad4020-4021-4022.pdf
Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/adaq4001.pdf
Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/adaq4003.pdf
Suggested-by: David Lechner <dlechner@baylibre.com>
Signed-off-by: Marcelo Schmitt <marcelo.schmitt@analog.com>
---
Even though didn't pick all suggestions to the dt-bindings, I did pick most them
so kept David's Suggested-by tag.
.../bindings/iio/adc/adi,ad4000.yaml | 207 ++++++++++++++++++
MAINTAINERS | 7 +
2 files changed, 214 insertions(+)
create mode 100644 Documentation/devicetree/bindings/iio/adc/adi,ad4000.yaml
diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad4000.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad4000.yaml
new file mode 100644
index 000000000000..7470d386906b
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/adc/adi,ad4000.yaml
@@ -0,0 +1,207 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/adc/adi,ad4000.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Analog Devices AD4000 and similar Analog to Digital Converters
+
+maintainers:
+ - Marcelo Schmitt <marcelo.schmitt@analog.com>
+
+description: |
+ Analog Devices AD4000 family of Analog to Digital Converters with SPI support.
+ Specifications can be found at:
+ https://www.analog.com/media/en/technical-documentation/data-sheets/ad4000-4004-4008.pdf
+ https://www.analog.com/media/en/technical-documentation/data-sheets/ad4001-4005.pdf
+ https://www.analog.com/media/en/technical-documentation/data-sheets/ad4002-4006-4010.pdf
+ https://www.analog.com/media/en/technical-documentation/data-sheets/ad4003-4007-4011.pdf
+ https://www.analog.com/media/en/technical-documentation/data-sheets/ad4020-4021-4022.pdf
+ https://www.analog.com/media/en/technical-documentation/data-sheets/adaq4001.pdf
+ https://www.analog.com/media/en/technical-documentation/data-sheets/adaq4003.pdf
+
+$ref: /schemas/spi/spi-peripheral-props.yaml#
+
+properties:
+ compatible:
+ enum:
+ - adi,ad4000
+ - adi,ad4001
+ - adi,ad4002
+ - adi,ad4003
+ - adi,ad4004
+ - adi,ad4005
+ - adi,ad4006
+ - adi,ad4007
+ - adi,ad4008
+ - adi,ad4010
+ - adi,ad4011
+ - adi,ad4020
+ - adi,ad4021
+ - adi,ad4022
+ - adi,adaq4001
+ - adi,adaq4003
+
+ reg:
+ maxItems: 1
+
+ spi-max-frequency:
+ maximum: 102040816 # for VIO > 2.7 V, 81300813 for VIO > 1.7 V
+
+ adi,spi-mode:
+ $ref: /schemas/types.yaml#/definitions/string
+ enum: [ single, chain ]
+ description: |
+ This property indicates the SPI wiring configuration.
+
+ When this property is omitted, it is assumed that the device is using what
+ the datasheet calls "4-wire mode". This is the conventional SPI mode used
+ when there are multiple devices on the same bus. In this mode, the CNV
+ line is used to initiate the conversion and the SDI line is connected to
+ CS on the SPI controller.
+
+ When this property is present, it indicates that the device is using one
+ of the following alternative wiring configurations:
+
+ * single: The datasheet calls this "3-wire mode". (NOTE: The datasheet's
+ definition of 3-wire mode is NOT at all related to the standard
+ spi-3wire property!) This mode is often used when the ADC is the only
+ device on the bus. In this mode, SDI is connected to MOSI or to VIO, and
+ the CNV line can be connected to the CS line of the SPI controller or to
+ a GPIO, in which case the CS line of the controller is unused.
+ * chain: The datasheet calls this "chain mode". This mode is used to save
+ on wiring when multiple ADCs are used. In this mode, the SDI line of
+ one chip is tied to the SDO of the next chip in the chain and the SDI of
+ the last chip in the chain is tied to GND. Only the first chip in the
+ chain is connected to the SPI bus. The CNV line of all chips are tied
+ together. The CS line of the SPI controller can be used as the CNV line
+ only if it is active high.
+
+ '#daisy-chained-devices': true
+
+ vdd-supply:
+ description: A 1.8V supply that powers the chip (VDD).
+
+ vio-supply:
+ description:
+ A 1.8V to 5.5V supply for the digital inputs and outputs (VIO).
+
+ ref-supply:
+ description:
+ A 2.5 to 5V supply for the external reference voltage (REF).
+
+ cnv-gpios:
+ description:
+ The Convert Input (CNV). This input has multiple functions. It initiates
+ the conversions and selects the SPI mode of the device (chain or CS). In
+ 'single' mode, this property is omitted if the CNV pin is connected to the
+ CS line of the SPI controller.
+ maxItems: 1
+
+ adi,high-z-input:
+ type: boolean
+ description:
+ High-Z mode allows the amplifier and RC filter in front of the ADC to be
+ chosen based on the signal bandwidth of interest, rather than the settling
+ requirements of the switched capacitor SAR ADC inputs.
+
+ adi,gain-milli:
+ description: |
+ The hardware gain applied to the ADC input (in milli units).
+ The gain provided by the ADC input scaler is defined by the hardware
+ connections between chip pins OUT+, R1K-, R1K1-, R1K+, R1K1+, and OUT-.
+ If not present, default to 1000 (no actual gain applied).
+ $ref: /schemas/types.yaml#/definitions/uint32
+ enum: [454, 909, 1000, 1900]
+ default: 1000
+
+ interrupts:
+ description:
+ The SDO pin can also function as a busy indicator. This node should be
+ connected to an interrupt that is triggered when the SDO line goes low
+ while the SDI line is high and the CNV line is low ('single' mode) or the
+ SDI line is low and the CNV line is high ('multi' mode); or when the SDO
+ line goes high while the SDI and CNV lines are high (chain mode),
+ maxItems: 1
+
+required:
+ - compatible
+ - reg
+ - vdd-supply
+ - vio-supply
+ - ref-supply
+
+allOf:
+ # in '4-wire' mode, cnv-gpios is required, for other modes it is optional
+ - if:
+ not:
+ required:
+ - adi,spi-mode
+ then:
+ required:
+ - cnv-gpios
+ # chain mode has lower SCLK max rate
+ - if:
+ required:
+ - adi,spi-mode
+ properties:
+ adi,spi-mode:
+ const: chain
+ then:
+ properties:
+ spi-max-frequency:
+ maximum: 50000000 # for VIO > 2.7 V, 40000000 for VIO > 1.7 V
+ required:
+ - '#daisy-chained-devices'
+ else:
+ properties:
+ '#daisy-chained-devices': false
+ # Gain property only applies to ADAQ devices
+ - if:
+ properties:
+ compatible:
+ not:
+ contains:
+ enum:
+ - adi,adaq4001
+ - adi,adaq4003
+ then:
+ properties:
+ adi,gain-milli: false
+
+unevaluatedProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/gpio/gpio.h>
+ spi {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ /* Example for a AD devices */
+ adc@0 {
+ compatible = "adi,ad4020";
+ reg = <0>;
+ spi-max-frequency = <71000000>;
+ vdd-supply = <&supply_1_8V>;
+ vio-supply = <&supply_1_8V>;
+ ref-supply = <&supply_5V>;
+ cnv-gpios = <&gpio0 88 GPIO_ACTIVE_HIGH>;
+ };
+ };
+ - |
+ spi {
+ #address-cells = <1>;
+ #size-cells = <0>;
+ /* Example for a ADAQ devices */
+ adc@0 {
+ compatible = "adi,adaq4003";
+ reg = <0>;
+ adi,spi-mode = "single";
+ spi-max-frequency = <80000000>;
+ vdd-supply = <&supply_1_8V>;
+ vio-supply = <&supply_1_8V>;
+ ref-supply = <&supply_5V>;
+ adi,high-z-input;
+ adi,gain-milli = <454>;
+ };
+ };
diff --git a/MAINTAINERS b/MAINTAINERS
index bff979a507ba..1f052b9cd912 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -1200,6 +1200,13 @@ W: https://ez.analog.com/linux-software-drivers
F: Documentation/devicetree/bindings/iio/dac/adi,ad3552r.yaml
F: drivers/iio/dac/ad3552r.c
+ANALOG DEVICES INC AD4000 DRIVER
+M: Marcelo Schmitt <marcelo.schmitt@analog.com>
+L: linux-iio@vger.kernel.org
+S: Supported
+W: https://ez.analog.com/linux-software-drivers
+F: Documentation/devicetree/bindings/iio/adc/adi,ad4000.yaml
+
ANALOG DEVICES INC AD4130 DRIVER
M: Cosmin Tanislav <cosmin.tanislav@analog.com>
L: linux-iio@vger.kernel.org
--
2.43.0On Tue, Jun 04, 2024 at 07:43:53PM -0300, Marcelo Schmitt wrote:
> Add device tree documentation for AD4000 series of ADC devices.
>
> Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ad4000-4004-4008.pdf
> Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ad4001-4005.pdf
> Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ad4002-4006-4010.pdf
> Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ad4003-4007-4011.pdf
> Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ad4020-4021-4022.pdf
> Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/adaq4001.pdf
> Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/adaq4003.pdf
>
> Suggested-by: David Lechner <dlechner@baylibre.com>
A suggested-by on a binding? That's unusual...
> Signed-off-by: Marcelo Schmitt <marcelo.schmitt@analog.com>
> ---
> Even though didn't pick all suggestions to the dt-bindings, I did pick most them
> so kept David's Suggested-by tag.
>
> .../bindings/iio/adc/adi,ad4000.yaml | 207 ++++++++++++++++++
> MAINTAINERS | 7 +
> 2 files changed, 214 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/iio/adc/adi,ad4000.yaml
>
> diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad4000.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad4000.yaml
> new file mode 100644
> index 000000000000..7470d386906b
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/adc/adi,ad4000.yaml
> @@ -0,0 +1,207 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/iio/adc/adi,ad4000.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Analog Devices AD4000 and similar Analog to Digital Converters
> +
> +maintainers:
> + - Marcelo Schmitt <marcelo.schmitt@analog.com>
> +
> +description: |
> + Analog Devices AD4000 family of Analog to Digital Converters with SPI support.
> + Specifications can be found at:
> + https://www.analog.com/media/en/technical-documentation/data-sheets/ad4000-4004-4008.pdf
> + https://www.analog.com/media/en/technical-documentation/data-sheets/ad4001-4005.pdf
> + https://www.analog.com/media/en/technical-documentation/data-sheets/ad4002-4006-4010.pdf
> + https://www.analog.com/media/en/technical-documentation/data-sheets/ad4003-4007-4011.pdf
> + https://www.analog.com/media/en/technical-documentation/data-sheets/ad4020-4021-4022.pdf
> + https://www.analog.com/media/en/technical-documentation/data-sheets/adaq4001.pdf
> + https://www.analog.com/media/en/technical-documentation/data-sheets/adaq4003.pdf
> +
> +$ref: /schemas/spi/spi-peripheral-props.yaml#
> +
> +properties:
> + compatible:
> + enum:
> + - adi,ad4000
> + - adi,ad4001
> + - adi,ad4002
> + - adi,ad4003
> + - adi,ad4004
> + - adi,ad4005
> + - adi,ad4006
> + - adi,ad4007
> + - adi,ad4008
> + - adi,ad4010
> + - adi,ad4011
> + - adi,ad4020
> + - adi,ad4021
> + - adi,ad4022
> + - adi,adaq4001
> + - adi,adaq4003
Are all these actually incompatible? I'd like a note in the commit
message as to why that's the case. A quick look at the driver showed
that the differences in the driver between the ad402{0,1,2} are limited
to the "dev_name". Same went for some other devices, like the
ad40{02,06,10}.
Thanks,
Conor.
On 06/05, Conor Dooley wrote:
> On Tue, Jun 04, 2024 at 07:43:53PM -0300, Marcelo Schmitt wrote:
> > Add device tree documentation for AD4000 series of ADC devices.
> >
> > Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ad4000-4004-4008.pdf
> > Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ad4001-4005.pdf
> > Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ad4002-4006-4010.pdf
> > Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ad4003-4007-4011.pdf
> > Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/ad4020-4021-4022.pdf
> > Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/adaq4001.pdf
> > Datasheet: https://www.analog.com/media/en/technical-documentation/data-sheets/adaq4003.pdf
> >
> > Suggested-by: David Lechner <dlechner@baylibre.com>
>
> A suggested-by on a binding? That's unusual...
>
> > Signed-off-by: Marcelo Schmitt <marcelo.schmitt@analog.com>
> > ---
> > Even though didn't pick all suggestions to the dt-bindings, I did pick most them
> > so kept David's Suggested-by tag.
> >
> > .../bindings/iio/adc/adi,ad4000.yaml | 207 ++++++++++++++++++
> > MAINTAINERS | 7 +
> > 2 files changed, 214 insertions(+)
> > create mode 100644 Documentation/devicetree/bindings/iio/adc/adi,ad4000.yaml
> >
> > diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad4000.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad4000.yaml
> > new file mode 100644
> > index 000000000000..7470d386906b
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/iio/adc/adi,ad4000.yaml
> > @@ -0,0 +1,207 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/iio/adc/adi,ad4000.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Analog Devices AD4000 and similar Analog to Digital Converters
> > +
> > +maintainers:
> > + - Marcelo Schmitt <marcelo.schmitt@analog.com>
> > +
> > +description: |
> > + Analog Devices AD4000 family of Analog to Digital Converters with SPI support.
> > + Specifications can be found at:
> > + https://www.analog.com/media/en/technical-documentation/data-sheets/ad4000-4004-4008.pdf
> > + https://www.analog.com/media/en/technical-documentation/data-sheets/ad4001-4005.pdf
> > + https://www.analog.com/media/en/technical-documentation/data-sheets/ad4002-4006-4010.pdf
> > + https://www.analog.com/media/en/technical-documentation/data-sheets/ad4003-4007-4011.pdf
> > + https://www.analog.com/media/en/technical-documentation/data-sheets/ad4020-4021-4022.pdf
> > + https://www.analog.com/media/en/technical-documentation/data-sheets/adaq4001.pdf
> > + https://www.analog.com/media/en/technical-documentation/data-sheets/adaq4003.pdf
> > +
> > +$ref: /schemas/spi/spi-peripheral-props.yaml#
> > +
> > +properties:
> > + compatible:
> > + enum:
> > + - adi,ad4000
> > + - adi,ad4001
> > + - adi,ad4002
> > + - adi,ad4003
> > + - adi,ad4004
> > + - adi,ad4005
> > + - adi,ad4006
> > + - adi,ad4007
> > + - adi,ad4008
> > + - adi,ad4010
> > + - adi,ad4011
> > + - adi,ad4020
> > + - adi,ad4021
> > + - adi,ad4022
> > + - adi,adaq4001
> > + - adi,adaq4003
>
> Are all these actually incompatible? I'd like a note in the commit
> message as to why that's the case. A quick look at the driver showed
> that the differences in the driver between the ad402{0,1,2} are limited
> to the "dev_name". Same went for some other devices, like the
> ad40{02,06,10}.
Yes, that's correct. Some chips only vary by name and max sample rate which
boils down to only having a different dev_name in the driver.
Can those have grouped compatible strings?
dt_binding_check fails if curly brackets are used.
properties:
compatible:
enum:
- adi,ad402{0,1,2}
The groups of similar chips are:
AD4020/AD4021/AD4022
AD4003/AD4007/AD4011
AD4002/AD4006/AD4010
AD4001/AD4005
AD4000/AD4004/AD4008
Thanks,
Marcelo
>
> Thanks,
> Conor.
On Fri, Jun 07, 2024 at 11:35:44AM -0300, Marcelo Schmitt wrote:
> On 06/05, Conor Dooley wrote:
> > On Tue, Jun 04, 2024 at 07:43:53PM -0300, Marcelo Schmitt wrote:
> > > Add device tree documentation for AD4000 series of ADC devices.
> > > +properties:
> > > + compatible:
> > > + enum:
> > > + - adi,ad4000
> > > + - adi,ad4001
> > > + - adi,ad4002
> > > + - adi,ad4003
> > > + - adi,ad4004
> > > + - adi,ad4005
> > > + - adi,ad4006
> > > + - adi,ad4007
> > > + - adi,ad4008
> > > + - adi,ad4010
> > > + - adi,ad4011
> > > + - adi,ad4020
> > > + - adi,ad4021
> > > + - adi,ad4022
> > > + - adi,adaq4001
> > > + - adi,adaq4003
> >
> > Are all these actually incompatible? I'd like a note in the commit
> > message as to why that's the case. A quick look at the driver showed
> > that the differences in the driver between the ad402{0,1,2} are limited
> > to the "dev_name". Same went for some other devices, like the
> > ad40{02,06,10}.
>
> Yes, that's correct. Some chips only vary by name and max sample rate which
> boils down to only having a different dev_name in the driver.
> Can those have grouped compatible strings?
> dt_binding_check fails if curly brackets are used.
> properties:
> compatible:
> enum:
> - adi,ad402{0,1,2}
compatible:
oneOf:
- const: adi,ad4020
- items:
- enum:
- adi,ad4021
- adi,ad4022
- const: adi,ad4020
>
> The groups of similar chips are:
> AD4020/AD4021/AD4022
> AD4003/AD4007/AD4011
> AD4002/AD4006/AD4010
> AD4001/AD4005
> AD4000/AD4004/AD4008
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