iio: magnetometer: Add support for MEMSIC MMC35240 sensor

Minimal implementation for MMC35240 3-axis magnetometer
sensor. It provides processed readings and possiblity to change
the sampling frequency.
Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

drivers/iio/magnetometer/Kconfig

@@ -47,6 +47,17 @@ config HID_SENSOR_MAGNETOMETER_3D
 	  Say yes here to build support for the HID SENSOR
 	  Magnetometer 3D.
 
+config MMC35240
+	tristate "MEMSIC MMC35240 3-axis magnetic sensor"
+	select REGMAP_I2C
+	depends on I2C
+	help
+	  Say yes here to build support for the MEMSIC MMC35240 3-axis
+	  magnetic sensor.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called mmc35240.
+
 config IIO_ST_MAGN_3AXIS
 	tristate "STMicroelectronics magnetometers 3-Axis Driver"
 	depends on (I2C || SPI_MASTER) && SYSFS

drivers/iio/magnetometer/Makefile

@@ -6,6 +6,7 @@
 obj-$(CONFIG_AK8975)	+= ak8975.o
 obj-$(CONFIG_MAG3110)	+= mag3110.o
 obj-$(CONFIG_HID_SENSOR_MAGNETOMETER_3D) += hid-sensor-magn-3d.o
+obj-$(CONFIG_MMC35240)	+= mmc35240.o
 
 obj-$(CONFIG_IIO_ST_MAGN_3AXIS) += st_magn.o
 st_magn-y := st_magn_core.o