IIO: ADC: New driver for AD7792/AD7793 3 Channel SPI ADC

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: Michael Hennerich <michael.hennerich@analog.com>
Acked-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 1 insertions, 0 deletions

diff --git a/drivers/staging/iio/adc/Makefile b/drivers/staging/iio/adc/Makefile
index 1d9b3f582eab..f02035139979 100644
--- a/drivers/staging/iio/adc/Makefile
+++ b/drivers/staging/iio/adc/Makefile
@@ -35,6 +35,7 @@ obj-$(CONFIG_AD7291) += ad7291.o
 obj-$(CONFIG_AD7314) += ad7314.o
 obj-$(CONFIG_AD7745) += ad7745.o
 obj-$(CONFIG_AD7780) += ad7780.o
+obj-$(CONFIG_AD7793) += ad7793.o
 obj-$(CONFIG_AD7816) += ad7816.o
 obj-$(CONFIG_ADT75) += adt75.o
 obj-$(CONFIG_ADT7310) += adt7310.o