RE: [PATCH v3 2/2] dt-bindings: iio: frequency: add admv1013 doc

[Miclaus, Antoniu]

> -----Original Message-----
> From: Jonathan Cameron <jic23@xxxxxxxxxx>
> Sent: Thursday, November 4, 2021 8:27 PM
> To: Miclaus, Antoniu <Antoniu.Miclaus@xxxxxxxxxx>
> Cc: Rob Herring <robh@xxxxxxxxxx>; linux-iio@xxxxxxxxxxxxxxx;
> devicetree@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Sa, Nuno
> <Nuno.Sa@xxxxxxxxxx>
> Subject: Re: [PATCH v3 2/2] dt-bindings: iio: frequency: add admv1013 doc
> 
> [External]
> 
> On Wed, 3 Nov 2021 14:30:56 +0000
> "Miclaus, Antoniu" <Antoniu.Miclaus@xxxxxxxxxx> wrote:
> 
> > Example:
> > In the setup that we tested the driver, we had a clock chip that was
> hardware-routed only to the positive side of the local oscillator input (LOP
> pin) from admv1013.
> >
> > Therefore, I think keeping the property in the DT might be useful.
> 
> I think Rob's question was more general than that one property... See below.
> >
> > Regards,
> > --
> > Antoniu Miclăuş
> >
> > > -----Original Message-----
> > > From: Miclaus, Antoniu
> > > Sent: Wednesday, November 3, 2021 10:09 AM
> > > To: Rob Herring <robh@xxxxxxxxxx>
> > > Cc: jic23@xxxxxxxxxx; linux-iio@xxxxxxxxxxxxxxx;
> devicetree@xxxxxxxxxxxxxxx;
> > > linux-kernel@xxxxxxxxxxxxxxx; Sa, Nuno <Nuno.Sa@xxxxxxxxxx>
> > > Subject: RE: [PATCH v3 2/2] dt-bindings: iio: frequency: add admv1013
> doc
> > >
> > > Hello Rob,
> > >
> > > These properties are fixed and available in the datasheet (binary format):
> > > https://www.analog.com/media/en/technical-documentation/data-
> > > sheets/ADMV1013.pdf
> > >
> > > Please see Page 37 of 39, Table 15, QUAD_SE_MODE.
> > >
> > > Regards,
> > > --
> > > Antoniu Miclăuş
> > >
> > > > -----Original Message-----
> > > > From: Rob Herring <robh@xxxxxxxxxx>
> > > > Sent: Tuesday, November 2, 2021 7:51 PM
> > > > To: Miclaus, Antoniu <Antoniu.Miclaus@xxxxxxxxxx>
> > > > Cc: jic23@xxxxxxxxxx; linux-iio@xxxxxxxxxxxxxxx;
> > > devicetree@xxxxxxxxxxxxxxx;
> > > > linux-kernel@xxxxxxxxxxxxxxx; Sa, Nuno <Nuno.Sa@xxxxxxxxxx>
> > > > Subject: Re: [PATCH v3 2/2] dt-bindings: iio: frequency: add admv1013
> doc
> > > >
> > > > [External]
> > > >
> > > > On Mon, Nov 01, 2021 at 12:04:20PM +0200, Antoniu Miclaus wrote:
> > > > > Add device tree bindings for the ADMV1013 Upconverter.
> > > > >
> > > > > Signed-off-by: Antoniu Miclaus <antoniu.miclaus@xxxxxxxxxx>
> > > > > ---
> > > > >  .../bindings/iio/frequency/adi,admv1013.yaml  | 119
> > > > ++++++++++++++++++
> > > > >  1 file changed, 119 insertions(+)
> > > > >  create mode 100644
> > > > Documentation/devicetree/bindings/iio/frequency/adi,admv1013.yaml
> > > > >
> > > > > diff --git
> > > >
> a/Documentation/devicetree/bindings/iio/frequency/adi,admv1013.yaml
> > > >
> b/Documentation/devicetree/bindings/iio/frequency/adi,admv1013.yaml
> > > > > new file mode 100644
> > > > > index 000000000000..47993253a586
> > > > > --- /dev/null
> > > > > +++
> > > >
> b/Documentation/devicetree/bindings/iio/frequency/adi,admv1013.yaml
> > > > > @@ -0,0 +1,119 @@
> > > > > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > > > > +%YAML 1.2
> > > > > +---
> > > > > +$id:
> > > >
> > >
> https://urldefense.com/v3/__http://devicetree.org/schemas/iio/frequency
> > > >
> > >
> /adi,admv1013.yaml*__;Iw!!A3Ni8CS0y2Y!uTDPalOgj6YS_vZ6bsDSbA_Qna6Q
> > > > OwMpoRxzo6nn06i5TNuGWZEk9PvtbC6SKQGXrugy$
> > > > > +$schema:
> https://urldefense.com/v3/__http://devicetree.org/meta-
> > > >
> > >
> schemas/core.yaml*__;Iw!!A3Ni8CS0y2Y!uTDPalOgj6YS_vZ6bsDSbA_Qna6Q
> > > > OwMpoRxzo6nn06i5TNuGWZEk9PvtbC6SKYugV1fM$
> > > > > +
> > > > > +title: ADMV1013 Microwave Upconverter
> > > > > +
> > > > > +maintainers:
> > > > > +  - Antoniu Miclaus <antoniu.miclaus@xxxxxxxxxx>
> > > > > +
> > > > > +description: |
> > > > > +   Wideband, microwave upconverter optimized for point to point
> > > > microwave
> > > > > +   radio designs operating in the 24 GHz to 44 GHz frequency range.
> > > > > +
> > > > > +   https://www.analog.com/en/products/admv1013.html
> > > > > +
> > > > > +properties:
> > > > > +  compatible:
> > > > > +    enum:
> > > > > +      - adi,admv1013
> > > > > +
> > > > > +  reg:
> > > > > +    maxItems: 1
> > > > > +
> > > > > +  spi-max-frequency:
> > > > > +    maximum: 1000000
> > > > > +
> > > > > +  clocks:
> > > > > +    description:
> > > > > +      Definition of the external clock.
> > > > > +    minItems: 1
> > > > > +
> > > > > +  clock-names:
> > > > > +    items:
> > > > > +      - const: lo_in
> > > > > +
> > > > > +  clock-output-names:
> > > > > +    maxItems: 1
> > > > > +
> > > > > +  vcm-supply:
> > > > > +    description:
> > > > > +      Analog voltage regulator.
> > > > > +
> > > > > +  adi,vga-powerdown:
> > > > > +    description:
> > > > > +      Power Down the Voltage Gain Amplifier Circuit available at
> > > > > +      BG_RBIAS2 pin.
> > > > > +    type: boolean
> 
> What wiring would make it sensible to always have this powered down?
> If we can describe that rather than vga-powerdown then that is what should
> be in the binding.  If there isn't any wiring based justification and this
> is just turning off part of the device, then it should not be in the binding.
> 
This part is similar to ADRF6780 that has also an Enable Register that can power down circuit blocks within the part:
https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio.git/tree/drivers/iio/frequency/adrf6780.c?h=togreg

I preferred to expose these properties in the device tree, rather than creating custom device attributes in the driver.

But I guess these properties can be managed also only from debug fs.

I can adapt the code based on your decision. Looking forward to your feedback.
> > > > > +
> > > > > +  adi,mixer-powerdown:
> > > > > +    description:
> > > > > +      Power Down the Mixer Circuit. Enable to put the block in
> > > > > +      a power down state.
> 
> Same for all these other power downs.
> 
> > > > > +    type: boolean
> > > > > +
> > > > > +  adi,quad-powerdown:
> > > > > +    description:
> > > > > +      Power Down the Quadrupler. Enable to put the block in
> > > > > +      a power down state.
> > > > > +    type: boolean
> > > > > +
> > > > > +  adi,bg-powerdown:
> > > > > +    description:
> > > > > +      Power Down the Transmitter Band Gap. Enable to put the part in
> > > > > +      a power down state.
> > > > > +    type: boolean
> > > > > +
> > > > > +  adi,mixer-if-enable:
> > > > > +    description:
> > > > > +      Enable the Intermediate Frequency Mode. Either IF Mode or I/Q
> > > Mode
> > > > > +      can be enabled at a time.
> > > > > +    type: boolean
> > > > > +
> > > > > +  adi,detector-enable:
> > > > > +    description:
> > > > > +      Enable the Envelope Detector available at output pins VENV_P
> and
> > > > > +      VENV_N. Disable to reduce power consumption.
> > > > > +    type: boolean
> > > > > +
> > > > > +  adi,quad-se-mode:
> > > > > +    description:
> > > > > +      Switch the LO path from differential to single-ended operation.
> > > > > +      Set value 6 for Single-Ended Mode, Negative Side Disabled.
> > > > > +      Set value 9 for Single-Ended Mode, Positive Side Disabled.
> > > > > +      Set value 12 for Differential Mode.
> > > > > +    $ref: /schemas/types.yaml#/definitions/uint32
> > > > > +    enum: [6, 9, 12]
> > > >
> > > > All these vendor properties are fixed based on the board design or
> > > > something a user may want to change? The latter does not belong in
> DT.
> > > >
> > > > Rob