On Tue, May 04, 2021 at 04:51:11PM +0200, Geert Uytterhoeven wrote:

Convert the Renesas R-Mobile I2C Bus Interface (IIC) Device Tree binding
documentation to json-schema.

Document missing properties.
R-Mobile A1 and SH-Mobile have multiple interrupts.
Update the example to match reality.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
It is still not clear to me which instances on R-Car Gen2 and RZ/G1
support automatic transmission, cfr. this note for the IIC3 instance in
the Hardware User's Manual:

    Automatic transmission for PMIC control (DVFS) is not available
    because the second generation R-Car series and RZ/G series products
    do not support the DVFS function (automatic transmission can be used
    as a hardware function, but this is not meaningful for actual use
    cases).

The only thing that's clear is that R-Car E2 and RZ/G1E do not have the
automatic transmission registers.  Note that current r8a7745.dtsi and
r8a7794.dtsi do not reflect that.

This binding interpretes the note as that IIC3 does not support
automatic transmission on R-Car H2, M2-W, M2-N, and V2H, and RZ/G1H,
RZ/H1M, RZ/G1N, while the other (if any) IIC instances on these SoCs do
support automatic transmission.  This matches with the current
r8a774[234].dtsi, which do not declare compatibility with the
family-specific and generic versions.  Note that the current
r8a779[0123].dtsi still do, and thus should be updated!

Possible alternative interpretations of the note are:
  - Only IIC3 has the automatic transmission registers.  But the
    automatic transmission feature is not useful as the SoCs lack DVFS
    support.
  - All IIC instances have the automatic transmission registers, and
    IIC3 is traditionally used to control the PMIC.  But as the SoCs
    lack DVFS support, the automatic transmission feature is not useful.
    As R-Car V2H has only instance IIC3, and is documented to have
    automatic transmissiong registers, this might be the correct
    interpration?
  - Anything else?

Can't help there, but looks fine otherwise.

Reviewed-by: Rob Herring <robh@kernel.org>

Thanks for your comments!
---
 .../devicetree/bindings/i2c/renesas,iic.txt   |  72 --------
 .../bindings/i2c/renesas,rmobile-iic.yaml     | 160 ++++++++++++++++++
 MAINTAINERS                                   |   2 +-
 3 files changed, 161 insertions(+), 73 deletions(-)
 delete mode 100644 Documentation/devicetree/bindings/i2c/renesas,iic.txt
 create mode 100644 Documentation/devicetree/bindings/i2c/renesas,rmobile-iic.yaml