Re: [PATCH 1/2] dt-bindings: wkup-m3-ipc: Add ti,scale-data-fw property

[Drew Fustini <dfustini@baylibre.com>]

On Mon, Apr 25, 2022 at 11:22:20AM -0500, Rob Herring wrote:
> On Sun, Apr 24, 2022 at 10:28:05PM -0700, Drew Fustini wrote:
> > From: Dave Gerlach <d-gerlach@ti.com>
> > 
> > Add documentation for ti,scale-data-fw property to enable I2C PMIC
> > voltage scaling during deep sleep. The property contains the name of a
> > binary file for the CM3 firmware to load.
> > 
> > Based on previous work by Russ Dill.
> > 
> > Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
> > Signed-off-by: Keerthy <j-keerthy@ti.com>
> > [dfustini: split from driver patch and convert to json-schema]
> > Signed-off-by: Drew Fustini <dfustini@baylibre.com>
> > ---
> >  .../devicetree/bindings/soc/ti/wkup-m3-ipc.yaml       | 11 +++++++++++
> >  1 file changed, 11 insertions(+)
> > 
> > diff --git a/Documentation/devicetree/bindings/soc/ti/wkup-m3-ipc.yaml b/Documentation/devicetree/bindings/soc/ti/wkup-m3-ipc.yaml
> > index 88d690de050c..d2c248d82384 100644
> > --- a/Documentation/devicetree/bindings/soc/ti/wkup-m3-ipc.yaml
> > +++ b/Documentation/devicetree/bindings/soc/ti/wkup-m3-ipc.yaml
> > @@ -40,6 +40,12 @@ description: |+
> >    override the pin's existing bias (pull-up/pull-down) and value (high/low) when
> >    IO isolation is active.
> >  
> > +  Support for I2C PMIC Voltage Scaling
> > +  ====================================
> > +  It is possible to pass the name of a binary file to load into the CM3 memory.
> > +  The binary data is the I2C sequences for the CM3 to send out to the PMIC
> > +  during low power mode entry.
> > +
> >  properties:
> >    compatible:
> >      enum:
> > @@ -67,6 +73,11 @@ properties:
> >        mbox_wkupm3 child node.
> >      maxItems: 1
> >  
> > +  ti,scale-data-fw:
> > +    $ref: /schemas/types.yaml#/definitions/string
> > +    description:
> > +      Name of the firmware binary in /lib/firmware to copy to CM3 aux data
> 
> The location of firmware files is up to the OS.
> 
> Is there other firmware? If not, 'firmware-name' is the somewhat 
> standard property for this.
> 
> What's the default name?

Thank you for the suggestion.  I will change it to firmware-name as
this is the only type of firmware that this driver will need to load.

There is no default name for the firmware. The name depends on the board
being used. The current [1] possibilites are:

am43x-evm-scale-data.bin
am335x-bone-scale-data.bin
am335x-evm-scale-data.bin

Thank you,
Drew

[1] https://git.ti.com/cgit/processor-firmware/ti-amx3-cm3-pm-firmware/tree/bin?h=08.02.00.006