Re: [PATCH v3 3/3] Docs: iio: Add AD4134

[Marcelo Schmitt <marcelo.schmitt1@gmail.com>]

On 12/03, Tomas Melin wrote:
> Hi,
> 
> On 02/12/2025 22:55, Marcelo Schmitt wrote:
> > Add initial documentation for the ad4134 IIO driver.
> 
> I wonder is there some information in here that is not readily available
> in the device datasheet? After all, isn't idea with this file to
> document peculiarities that are not easily found elsewhere?

You are correct, these docs are mostly from data sheet info.
The main idea of having the doc is to make clear what peripheral connection
schema is currently supported.
Because AD4134 is both flexible and somewhat extensible in the way it can be
connected to the host, we could have different wiring configurations, for
example

                                                              +-------------+
  +----------------------+                                    |  DATA HOST  |
  |       AD4134         |                                    |             |
  |                      |                                    |             |
  |Data interface  DOUT0 |----------------------------------->| GPI0        |
  |for ADC data    DOUT1 |----------------------------------->| GPI1        |
  |read back       DOUT2 |----------------------------------->| GPI2        |
  |                DOUT3 |----------------------------------->| GPI3        |
  |                DCLK  |<--------------+        +---------->| GPI4        |
  |                ODR   |<------------+ |        | +-------->| GPI5        |
  |                      |             | |        | | +------>| GPI6        |
  |                      |             | |        | | | +---->| GPI7        |
  | SPI interface   CS   |<-------+    | +--------|-|-|-|-----| DCLK        |
  | for register    SCLK |<-----+ |    |          | | | |     |             |
  | access          SDI  |<---+ | |    |          | | | |     | TRIGGER     |
  |                 SDO  |--+ | | |    |          | | | |     +-------------+
  +----------------------+  | | | |    +----------|-|-|-|---------+
                            | | | +---------------+ | | |
                            | | +-------------------+ | |
                            | +-----------------------+ |
                            +---------------------------+

or even with two devices [1].
[1]: https://lore.kernel.org/linux-iio/aRIIDTUR5Pyz1Rxi@debian-BULLSEYE-live-builder-AMD64/

That is not a current use case but it could be possible. I think it's likely we
will need extra software to support those cases and, when we get to that, we
would be adding more diagrams to this doc. Still, no strong opinion, we can
alternatively add the doc only when we get to those more complex cases.
I'll follow reviewers' preferences if you or anybody else express any.

Best regards,
Marcelo