[PATCH v4 0/4] iio: add unit-converter

From: Peter Rosin
Date: Mon Apr 23 2018 - 17:08:29 EST


This driver implements support for voltage dividers, current sense
shunts and current sense amplifiers. It's pretty generic and should
be easily adaptable to other linear scaling purposes.


Changes since v3: https://lkml.org/lkml/2018/4/10/614
- Split the bindings patch for voltage-divider and current-sense-shunt
in two, thus retaining the tag from Rob on the latter, when the
former got a major update. The voltage-divider binding is now
clear of its history from the generic io-channel-unit-converter
binding roots (v1 of the series) and makes much more sense on its
own (IMHO).
- Incorporate the confusing followup patches that added current sense
amplification to the series.
- Drop the adi,lt6106 binding from that followup and replace it with
a generic current-sense-amplifier binding.
- Adjust the driver to the above, and also rename it to iio-rescale
as unit-converter was perhaps a little bit too generic even for the
driver name.

Changes since v2: https://lkml.org/lkml/2018/4/3/461
- Rename from current-sence-circuit to current-sense-shunt (this
should also fix all the typing problems I had with curciut).
- Describe the shunt resistance directly (instead of indirectly
in the form of a quotient).
- Add a ->props() op to struct unit_converter_cfg to enable simple
separation of properties for different converters.
- Shuffle the code around to minimize forward declarations.
- Drop the unused indio member from struct unit_converter.
- Drop error report on iio driver registration failure.

Changes since v1: https://lkml.org/lkml/2018/3/19/801
- Put the driver in the new afe category (Analog Front Ends) and do not
move the iio-mux driver.
- Do not refer to the source channel as "parent", use "source" instead.
- Have the DT compatible drive the target unit, instead of relying on a
"type" DT-property for that.
- In the DT bindings, use an unnamed source channel.
- Do not set up writes to _RAW (sorry Phil) as I don't need it and have
not tested it. It's easy to add back if needed.
- Fail if the source channel does not support _RAW or _SCALE.
- Fix various spelling issues.
- Fix various code style issues.

Peter Rosin (4):
dt-bindings: iio: afe: add binding for current-sense-shunt
dt-bindings: iio: afe: add binding for voltage-divider
dt-bindings: iio: afe: add binding for current-sense-amplifier
iio: afe: rescale: new driver

.../bindings/iio/afe/current-sense-amplifier.txt | 26 ++
.../bindings/iio/afe/current-sense-shunt.txt | 41 +++
.../bindings/iio/afe/voltage-divider.txt | 53 +++
drivers/iio/Kconfig | 1 +
drivers/iio/Makefile | 1 +
drivers/iio/afe/Kconfig | 19 ++
drivers/iio/afe/Makefile | 6 +
drivers/iio/afe/iio-rescale.c | 359 +++++++++++++++++++++
9 files changed, 515 insertions(+)
create mode 100644 Documentation/devicetree/bindings/iio/afe/current-sense-amplifier.txt
create mode 100644 Documentation/devicetree/bindings/iio/afe/current-sense-shunt.txt
create mode 100644 Documentation/devicetree/bindings/iio/afe/voltage-divider.txt
create mode 100644 drivers/iio/afe/Kconfig
create mode 100644 drivers/iio/afe/Makefile
create mode 100644 drivers/iio/afe/iio-rescale.c