iio: adc: Add Maxim max9611 ADC driver

Add iio driver for Maxim max9611 and max9612 current-sense amplifiers
with 12-bits ADC interface.

Datasheet publicly available at:
https://datasheets.maximintegrated.com/en/ds/MAX9611-MAX9612.pdfSigned-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

drivers/iio/adc/Kconfig

@@ -398,6 +398,16 @@ config MAX1363
 	  To compile this driver as a module, choose M here: the module will be
 	  called max1363.
 
+config	MAX9611
+	tristate "Maxim max9611/max9612 ADC driver"
+	depends on I2C
+	help
+	  Say yes here to build support for Maxim max9611/max9612 current sense
+	  amplifier with 12-bits ADC interface.
+
+	  To compile this driver as a module, choose M here: the module will be
+	  called max9611.
+
 config MCP320X
 	tristate "Microchip Technology MCP3x01/02/04/08"
 	depends on SPI

drivers/iio/adc/Makefile

@@ -38,6 +38,7 @@ obj-$(CONFIG_LTC2497) += ltc2497.o
 obj-$(CONFIG_MAX1027) += max1027.o
 obj-$(CONFIG_MAX11100) += max11100.o
 obj-$(CONFIG_MAX1363) += max1363.o
+obj-$(CONFIG_MAX9611) += max9611.o
 obj-$(CONFIG_MCP320X) += mcp320x.o
 obj-$(CONFIG_MCP3422) += mcp3422.o
 obj-$(CONFIG_MEDIATEK_MT6577_AUXADC) += mt6577_auxadc.o