RE: [PATCH v3 01/27] dt-bindings: iio: resolver: add devicetree bindings for ad2s1210

[Hennerich, Michael]

> -----Original Message-----
> From: Jonathan Cameron <jic23@xxxxxxxxxx>
> Sent: Samstag, 30. September 2023 16:34
> To: David Lechner <dlechner@xxxxxxxxxxxx>
> Cc: linux-iio@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; linux-
> staging@xxxxxxxxxxxxxxx; David Lechner <david@xxxxxxxxxxxxxx>; Rob Herring
> <robh+dt@xxxxxxxxxx>; Krzysztof Kozlowski
> <krzysztof.kozlowski+dt@xxxxxxxxxx>; Conor Dooley <conor+dt@xxxxxxxxxx>;
> Hennerich, Michael <Michael.Hennerich@xxxxxxxxxx>; Sa, Nuno
> <Nuno.Sa@xxxxxxxxxx>; Axel Haslam <ahaslam@xxxxxxxxxxxx>; Philip Molloy
> <pmolloy@xxxxxxxxxxxx>; linux-kernel@xxxxxxxxxxxxxxx; Apelete Seketeli
> <aseketeli@xxxxxxxxxxxx>
> Subject: Re: [PATCH v3 01/27] dt-bindings: iio: resolver: add devicetree
> bindings for ad2s1210
> 
> 
> On Fri, 29 Sep 2023 12:23:06 -0500
> David Lechner <dlechner@xxxxxxxxxxxx> wrote:
> 
> > From: David Lechner <david@xxxxxxxxxxxxxx>
> >
> > From: David Lechner <dlechner@xxxxxxxxxxxx>
> >
> > This adds new DeviceTree bindings for the Analog Devices, Inc.
> > AD2S1210 resolver-to-digital converter.
> >
> > Co-developed-by: Apelete Seketeli <aseketeli@xxxxxxxxxxxx>
> > Signed-off-by: Apelete Seketeli <aseketeli@xxxxxxxxxxxx>
> > Signed-off-by: David Lechner <dlechner@xxxxxxxxxxxx>
> 
> Michael, ideally I'd like your ack on this given it volunteers you as maintainer. If
> I don't hear I'm fine with leaving Michael listed because he's in MAINTAINERS
> anyway covering these bindings via a wild card entry:

Acked-by: Michael Hennerich <michael.hennerich@xxxxxxxxxx>

> 
> ANALOG DEVICES INC IIO DRIVERS
> M:	Lars-Peter Clausen <lars@xxxxxxxxxx>
> M:	Michael Hennerich <Michael.Hennerich@xxxxxxxxxx>
> ...
> F:	Documentation/devicetree/bindings/iio/*/adi,*
> 
> So any queries should hit Michael anyway.
> 
> LGTM but I'll also want the dt binding maintainers input before picking this up.
> 
> Jonathan
> 
> > ---
> >
> > v3 changes:
> > * Expanded top-level description of A0/A1 lines.
> > * Added required voltage -supply properties. (I did not pick up Rob's
> >   Reviewed-by since I wasn't sure if this was trivial enough.)
> >
> > v2 changes:
> > * Add Co-developed-by:
> > * Remove extraneous quotes on strings
> > * Remove extraneous pipe on some multi-line descriptions
> >
> >  .../bindings/iio/resolver/adi,ad2s1210.yaml        | 177
> +++++++++++++++++++++
> >  1 file changed, 177 insertions(+)
> >
> > diff --git
> > a/Documentation/devicetree/bindings/iio/resolver/adi,ad2s1210.yaml
> > b/Documentation/devicetree/bindings/iio/resolver/adi,ad2s1210.yaml
> > new file mode 100644
> > index 000000000000..8980b3cd8337
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/iio/resolver/adi,ad2s1210.yaml
> > @@ -0,0 +1,177 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) %YAML 1.2
> > +---
> > +$id:
> > +https://urldefense.com/v3/__http://devicetree.org/schemas/iio/resolve
> >
> +r/adi,ad2s1210.yaml*__;Iw!!A3Ni8CS0y2Y!_mSGRdlDHlqAKev0r38paa3K51l2k
> G
> > +o8bShqK2TH4nAF_cYu2WixIa62xv0p-A70086DQmj4oN9FWvOlk78$
> > +$schema:
> > +https://urldefense.com/v3/__http://devicetree.org/meta-schemas/core.y
> >
> +aml*__;Iw!!A3Ni8CS0y2Y!_mSGRdlDHlqAKev0r38paa3K51l2kGo8bShqK2TH4n
> AF_c
> > +Yu2WixIa62xv0p-A70086DQmj4oN9FWzdE10U$
> > +
> > +title: Analog Devices AD2S1210 Resolver-to-Digital Converter
> > +
> > +maintainers:
> > +  - Michael Hennerich <michael.hennerich@xxxxxxxxxx>
> > +
> > +description: |
> > +  The AD2S1210 is a complete 10-bit to 16-bit resolution tracking
> > +  resolver-to-digital converter, integrating an on-board programmable
> > +  sinusoidal oscillator that provides sine wave excitation for
> > +  resolvers.
> > +
> > +  The AD2S1210 allows the user to read the angular position or the
> > + angular velocity data directly from the parallel outputs or through
> > + the serial interface.
> > +
> > +  The mode of operation of the communication channel (parallel or
> > + serial) is  selected by the A0 and A1 input pins. In normal mode,
> > + data is latched by  toggling the SAMPLE line and can then be read
> > + directly. In configuration mode,  data is read or written using a
> > + register access scheme (address byte with  read/write flag and data byte).
> > +
> > +    A1  A0  Result
> > +     0   0  Normal mode - position output
> > +     0   1  Normal mode - velocity output
> > +     1   0  Reserved
> > +     1   1  Configuration mode
> > +
> > +  In normal mode, the resolution of the digital output is selected
> > + using  the RES0 and RES1 input pins. In configuration mode, the
> > + resolution is  selected by setting the RES0 and RES1 bits in the control
> register.
> > +
> > +  RES1  RES0  Resolution (Bits)
> > +     0     0  10
> > +     0     1  12
> > +     1     0  14
> > +     1     1  16
> > +
> > +  Note on SPI connections: The CS line on the AD2S1210 should
> > + hard-wired to  logic low and the WR/FSYNC line on the AD2S1210
> > + should be connected to the  SPI CSn output of the SPI controller.
> > +
> > +  Datasheet:
> > +
> > + https://www.analog.com/media/en/technical-documentation/data-sheets/
> > + ad2s1210.pdf
> > +
> > +properties:
> > +  compatible:
> > +    const: adi,ad2s1210
> > +
> > +  reg:
> > +    maxItems: 1
> > +
> > +  spi-max-frequency:
> > +    maximum: 25000000
> > +
> > +  spi-cpha: true
> > +
> > +  avdd-supply:
> > +    description:
> > +      A 4.75 to 5.25 V regulator that powers the Analog Supply Voltage
> (AVDD)
> > +      pin.
> > +
> > +  dvdd-supply:
> > +    description:
> > +      A 4.75 to 5.25 V regulator that powers the Digital Supply Voltage (DVDD)
> > +      pin.
> > +
> > +  vdrive-supply:
> > +    description:
> > +      A 2.3 to 5.25 V regulator that powers the Logic Power Supply Input
> > +      (VDrive) pin.
> > +
> > +  clocks:
> > +    maxItems: 1
> > +    description: External oscillator clock (CLKIN).
> > +
> > +  reset-gpios:
> > +    description:
> > +      GPIO connected to the /RESET pin. As the line needs to be low for the
> > +      reset to be active, it should be configured as GPIO_ACTIVE_LOW.
> > +    maxItems: 1
> > +
> > +  sample-gpios:
> > +    description:
> > +      GPIO connected to the /SAMPLE pin. As the line needs to be low to
> trigger
> > +      a sample, it should be configured as GPIO_ACTIVE_LOW.
> > +    maxItems: 1
> > +
> > +  mode-gpios:
> > +    description:
> > +      GPIO lines connected to the A0 and A1 pins. These pins select the data
> > +      transfer mode.
> > +    minItems: 2
> > +    maxItems: 2
> > +
> > +  resolution-gpios:
> > +    description:
> > +      GPIO lines connected to the RES0 and RES1 pins. These pins select the
> > +      resolution of the digital output. If omitted, it is assumed that the
> > +      RES0 and RES1 pins are hard-wired to match the assigned-resolution-bits
> > +      property.
> > +    minItems: 2
> > +    maxItems: 2
> > +
> > +  fault-gpios:
> > +    description:
> > +      GPIO lines connected to the LOT and DOS pins. These pins combined
> indicate
> > +      the type of fault present, if any. As these pins a pulled low to indicate
> > +      a fault condition, they should be configured as GPIO_ACTIVE_LOW.
> > +    minItems: 2
> > +    maxItems: 2
> > +
> > +  adi,fixed-mode:
> > +    description:
> > +      This is used to indicate the selected mode if A0 and A1 are hard-wired
> > +      instead of connected to GPIOS (i.e. mode-gpios is omitted).
> > +    $ref: /schemas/types.yaml#/definitions/string
> > +    enum: [config, velocity, position]
> > +
> > +  assigned-resolution-bits:
> > +    description:
> > +      Resolution of the digital output required by the application. This
> > +      determines the precision of the angle and/or the maximum speed that
> can
> > +      be measured. If resolution-gpios is omitted, it is assumed that RES0 and
> > +      RES1 are hard-wired to match this value.
> > +    enum: [10, 12, 14, 16]
> > +
> > +required:
> > +  - compatible
> > +  - reg
> > +  - spi-cpha
> > +  - avdd-supply
> > +  - dvdd-supply
> > +  - vdrive-supply
> > +  - clocks
> > +  - sample-gpios
> > +  - assigned-resolution-bits
> > +
> > +oneOf:
> > +  - required:
> > +      - mode-gpios
> > +  - required:
> > +      - adi,fixed-mode
> > +
> > +allOf:
> > +  - $ref: /schemas/spi/spi-peripheral-props.yaml#
> > +
> > +unevaluatedProperties: false
> > +
> > +examples:
> > +  - |
> > +    #include <dt-bindings/gpio/gpio.h>
> > +
> > +    spi {
> > +        #address-cells = <1>;
> > +        #size-cells = <0>;
> > +
> > +        resolver@0 {
> > +            compatible = "adi,ad2s1210";
> > +            reg = <0>;
> > +            spi-max-frequency = <20000000>;
> > +            spi-cpha;
> > +            avdd-supply = <&avdd_regulator>;
> > +            dvdd-supply = <&dvdd_regulator>;
> > +            vdrive-supply = <&vdrive_regulator>;
> > +            clocks = <&ext_osc>;
> > +            sample-gpios = <&gpio0 90 GPIO_ACTIVE_LOW>;
> > +            mode-gpios = <&gpio0 86 0>, <&gpio0 87 0>;
> > +            resolution-gpios = <&gpio0 88 0>, <&gpio0 89 0>;
> > +            assigned-resolution-bits = <16>;
> > +        };
> > +    };
> >