iio: Add Freescale mag3110 magnetometer driver

three-axis digital magnetometer with I2C interface

datasheet is available from
http://cache.freescale.com/files/sensors/doc/data_sheet/MAG3110.pdf

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
diff --git a/drivers/iio/magnetometer/Kconfig b/drivers/iio/magnetometer/Kconfig
index 4fa923f..0cf0963 100644
--- a/drivers/iio/magnetometer/Kconfig
+++ b/drivers/iio/magnetometer/Kconfig
@@ -16,6 +16,16 @@
 	  To compile this driver as a module, choose M here: the module
 	  will be called ak8975.
 
+config MAG3110
+	tristate "Freescale MAG3110 3-Axis Magnetometer"
+	depends on I2C
+	help
+	  Say yes here to build support for the Freescale MAG3110 3-Axis
+	  magnetometer.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called mag3110.
+
 config HID_SENSOR_MAGNETOMETER_3D
 	depends on HID_SENSOR_HUB
 	select IIO_BUFFER