iio: magn: Split bmc150 driver in common/i2c parts

This is useful for easily adding SPI support in later patches.

Now bmc150_magn exports core functions to be used by I2C/SPI drivers
instances. For the moment only I2C driver is supported.

Signed-off-by: Daniel Baluta <[email protected]>
Acked-by: Irina Tirdea <[email protected]>
Signed-off-by: Jonathan Cameron <[email protected]>

drivers/iio/magnetometer/Kconfig

@@ -27,22 +27,25 @@ config AK09911
 	  Deprecated: AK09911 is now supported by AK8975 driver.
 
 config BMC150_MAGN
-	tristate "Bosch BMC150 Magnetometer Driver"
-	depends on I2C
-	select REGMAP_I2C
+	tristate
 	select IIO_BUFFER
 	select IIO_TRIGGERED_BUFFER
-	help
-	  Say yes here to build support for the BMC150 magnetometer.
 
-	  Currently this only supports the device via an i2c interface.
+config BMC150_MAGN_I2C
+	tristate "Bosch BMC150 I2C Magnetometer Driver"
+	depends on I2C
+	select BMC150_MAGN
+	select REGMAP_I2C
+	help
+	  Say yes here to build support for the BMC150 magnetometer with
+	  I2C interface.
 
 	  This is a combo module with both accelerometer and magnetometer.
 	  This driver is only implementing magnetometer part, which has
 	  its own address and register map.
 
 	  To compile this driver as a module, choose M here: the module will be
-	  called bmc150_magn.
+	  called bmc150_magn_i2c.
 
 config MAG3110
 	tristate "Freescale MAG3110 3-Axis Magnetometer"

drivers/iio/magnetometer/Makefile

@@ -5,6 +5,8 @@
 # When adding new entries keep the list in alphabetical order
 obj-$(CONFIG_AK8975)	+= ak8975.o
 obj-$(CONFIG_BMC150_MAGN) += bmc150_magn.o
+obj-$(CONFIG_BMC150_MAGN_I2C) += bmc150_magn_i2c.o
+
 obj-$(CONFIG_MAG3110)	+= mag3110.o
 obj-$(CONFIG_HID_SENSOR_MAGNETOMETER_3D) += hid-sensor-magn-3d.o
 obj-$(CONFIG_MMC35240)	+= mmc35240.o