mfd: Add Intel MSIC driver

Add support for Intel MSIC chip found on Intel Medfield platforms. This
chip embeds several subdevices: audio, ADC, GPIO, power button, etc. The
driver creates platform device for each subdevice.

We also provide an MSIC register access API which should replace the more
generic SCU IPC interface currently used. Existing drivers can choose
whether they convert to this new API or stick with the SCU IPC interface.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

drivers/mfd/Kconfig

@@ -757,6 +757,15 @@ config MFD_AAT2870_CORE
 	  additional drivers must be enabled in order to use the
 	  functionality of the device.
 
+config MFD_INTEL_MSIC
+	bool "Support for Intel MSIC"
+	depends on INTEL_SCU_IPC
+	select MFD_CORE
+	help
+	  Select this option to enable access to Intel MSIC (Avatele
+	  Passage) chip. This chip embeds audio, battery, GPIO, etc.
+	  devices used in Intel Medfield platforms.
+
 endmenu
 endif
 

drivers/mfd/Makefile

@@ -102,3 +102,4 @@ obj-$(CONFIG_MFD_PM8921_CORE) 	+= pm8921-core.o
 obj-$(CONFIG_MFD_PM8XXX_IRQ) 	+= pm8xxx-irq.o
 obj-$(CONFIG_TPS65911_COMPARATOR)	+= tps65911-comparator.o
 obj-$(CONFIG_MFD_AAT2870_CORE)	+= aat2870-core.o
+obj-$(CONFIG_MFD_INTEL_MSIC)	+= intel_msic.o