On Thu, Feb 22, 2024 at 9:34 AM Rob Herring <robh@xxxxxxxxxx> wrote: > > On Wed, Feb 21, 2024 at 8:44 AM David Lechner <dlechner@xxxxxxxxxxxx> wrote: > > > > On Wed, Feb 21, 2024 at 9:22 AM Rob Herring <robh@xxxxxxxxxx> wrote: > > > > > > On Fri, Feb 16, 2024 at 01:46:18PM -0600, David Lechner wrote: > > > > ... > > > > > > + adi,spi-mode: > > > > + $ref: /schemas/types.yaml#/definitions/string > > > > + enum: [ single, multi, chain ] > > > > + default: multi > > > > + description: | > > > > + * single: The datasheet calls this "3-wire mode". It is often used when > > > > + the ADC is the only device on the bus. In this mode, SDI is tied 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. > > > > > > We have a standard property for this. > > > > As discussed in v1 [1], the datasheet's definition of "3-wire mode" is > > _not_ the same as the standard spi-3wire property. I can add that to > > the description here to clarify (I hoped changing the enum name was > > enough, but perhaps not). Or is there a different property you are > > referring to? > > > > [1]: https://lore.kernel.org/all/20240216140826.58b3318d@jic23-huawei/ > > > > > > > > > + * multi: The datasheet calls this "4-wire mode". This is the convential > > Also, typo. > > > > > + 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. > > > > > > That's "normal" mode. > > > > That was my first choice, but the datasheet uses the term "normal > > mode" to mean not TURBO mode which is something else unrelated to the > > SPI mode. > > What I mean is this should be conveyed by the absence of any property. > You don't need a property for "normal SPI mode". The binding already has `default: multi` to cover this case. But I suppose we can just leave out the option altogether if you prefer.
