The driver does not expose any custom API to userspace and none of the standard
static code checker tools report any issues, so move it out of staging.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

The only user of the register definitions is the driver itself, so move them
from the header file to the driver source file. The header file now only
contains the platform data struct.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Rework the regulator handling of the driver to match more closely what we do in
other drivers. Make the regulator non-optional if a external reference is used.
Also dispose the option of specifying the reference voltage via platform data.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Currently the platform data for the ad7793 consist just out of the raw default
register settings. This has some downsides, for one we actually don't want to
make all bits configurable and secondly not all register settings are actually
valid. This patch exposes all the options which should be configurable via
platform data as induvidual platform data struct fields. This also allows us to
document the different settings via proper kernel doc.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

The ad7794/ad7795 are similar to the ad7792/ad7793, but have 6 channels instead
of 3.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

Convert the ad7793 driver to make use of the new common code for devices from
the Analog Devices Sigma Delta family.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

New driver for AD7792/AD7793 3-Channel, Low Noise,
Low Power, 16-/24-Bit Sigma-Delta ADC with On-Chip In-Amp
and Reference.

The AD7792/AD7793 features a dual use data out ready DOUT/RDY output.
In order to avoid contentions on the SPI bus, it's necessary to use
spi bus locking. The DOUT/RDY output must also be wired to an
interrupt capable GPIO.

In INDIO_RING_TRIGGERED mode, this driver may block its SPI bus segment
for an extended period of time.

Changes since V1:

Use bool where applicable.
Use data buffer that lives in their own cache line.
Restructure ad7793_calibrate_all to use an array.
Use msleep.
Query REG_ID instead of doing a write/read This is a test.
Add support for unipolar mode.
Drop range attribute in favor of write scale.
Add proper locking.
Use new validate_trigger callbacks.
Use IIO_IN_DIFF for differential channels.
Change attribute naming.
Use available_scan_masks.
Some other miscellaneous cleanup (none functional changes).
Signed-off-by: NMichael Hennerich <michael.hennerich@analog.com>
Acked-by: NJonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>