Re: [PATCH v2 0/3] Add support for LTC2688

[Jonathan Cameron <jic23@kernel.org>]

>   * Have a clock property per channel. Note that we this I moved to OF
> since we now have to use 'devm_get_clk_from_child()' which is using
> device_node. Note that I could use 'to_of_node()' but mixing of.h and
> property.h does not feel like a good idea.

Ah, that's unfortunate given the clk is only needed in certain modes...

Andy/Rafael/Rob, any thoughts on how we should handle this?  Obviously
ACPI and clocks is generally a no go, but in this particular case we
aren't looking at a power management related use of clocks, but rather
using the clk framework to provide a way to control one of our inputs
used to generate the output dithered signal...  If the device just its
own clock then we'd just control it directly with no problems, but it uses
and external source.

We don't know of anyone actually looking at this device in conjunction with
ACPI so maybe just using dt specific calls for now rather than generic
firmware properties is the best we can do.

Thanks,

Jonathan

> 
>  ABI:
>   * Added out_voltageY_raw0 ABI for toggle mode;
>   * Added out_voltageY_dither_offset.
> 
>  Bindings:
>   * Use standard microvolt unit;
>   * Added constrains for adi,output-range-microvolt and removed negative
> values from the dts example;
>   * Moved clocks to the channel object;
>   * Dropped clock-names;
>   * Add a dependency between 'adi,toggle-dither-input' and 'clocks'.
>  
> [1]: https://marc.info/?l=linux-iio&m=163662843603265&w=2
> 
> Nuno Sá (3):
>   iio: dac: add support for ltc2688
>   iio: ABI: add ABI file for the LTC2688 DAC
>   dt-bindings: iio: Add ltc2688 documentation
> 
>  .../ABI/testing/sysfs-bus-iio-dac-ltc2688     |   80 ++
>  .../bindings/iio/dac/adi,ltc2688.yaml         |  147 +++
>  MAINTAINERS                                   |    9 +
>  drivers/iio/dac/Kconfig                       |   11 +
>  drivers/iio/dac/Makefile                      |    1 +
>  drivers/iio/dac/ltc2688.c                     | 1070 +++++++++++++++++
>  6 files changed, 1318 insertions(+)
>  create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-dac-ltc2688
>  create mode 100644 Documentation/devicetree/bindings/iio/dac/adi,ltc2688.yaml
>  create mode 100644 drivers/iio/dac/ltc2688.c
>