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

Hennerich, Michael
2023-10-04T10:42:10Z

> -----Original Message-----
> From: Jonathan Cameron <jic23@kernel.org>
> Sent: Samstag, 30. September 2023 16:34
> To: David Lechner <dlechner@baylibre.com>
> Cc: linux-iio@vger.kernel.org; devicetree@vger.kernel.org; linux-
> staging@lists.linux.dev; David Lechner <david@lechnology.com>; Rob Herring
> <robh+dt@kernel.org>; Krzysztof Kozlowski
> <krzysztof.kozlowski+dt@linaro.org>; Conor Dooley <conor+dt@kernel.org>;
> Hennerich, Michael <Michael.Hennerich@analog.com>; Sa, Nuno
> <Nuno.Sa@analog.com>; Axel Haslam <ahaslam@baylibre.com>; Philip Molloy
> <pmolloy@baylibre.com>; linux-kernel@vger.kernel.org; Apelete Seketeli
> <aseketeli@baylibre.com>
> 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@baylibre.com> wrote:
>
> > From: David Lechner <david@lechnology.com>
> >
> > From: David Lechner <dlechner@baylibre.com>
> >
> > This adds new DeviceTree bindings for the Analog Devices, Inc.
> > AD2S1210 resolver-to-digital converter.
> >
> > Co-developed-by: Apelete Seketeli <aseketeli@baylibre.com>
> > Signed-off-by: Apelete Seketeli <aseketeli@baylibre.com>
> > Signed-off-by: David Lechner <dlechner@baylibre.com>
>
> 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@analog.com>

>
> ANALOG DEVICES INC IIO DRIVERS
> M: Lars-Peter Clausen <lars@metafoo.de>
> M: Michael Hennerich <Michael.Hennerich@analog.com>
> ...
> 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@analog.com>
> > +
> > +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>;
> > + };
> > + };
> >