Extcon: Arizona: Add driver for Wolfson Arizona class devices

Most Wolfson Arizona class audio hub CODECs include a flexible ultra low
power accessory detection subsystem. This driver exposes initial support
for this subsystem via the Extcon framework, implementing support for
ultra low power detection of headphone and headset with the ability to
detect the polarity of a headset.

The functionality of the devices is much richer and more flexible than
the current driver, future patches will extend the features of the
driver to more fully exploit this.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/extcon/Kconfig

@@ -29,4 +29,12 @@ config EXTCON_MAX8997
 	  Maxim MAX8997 PMIC. The MAX8997 MUIC is a USB port accessory
 	  detector and switch.
 
+config EXTCON_ARIZONA
+	tristate "Wolfson Arizona EXTCON support"
+	depends on MFD_ARIZONA
+	help
+	  Say Y here to enable support for external accessory detection
+	  with Wolfson Arizona devices. These are audio CODECs with
+	  advanced audio accessory detection support.
+
 endif # MULTISTATE_SWITCH

drivers/extcon/Makefile

@@ -5,3 +5,4 @@
 obj-$(CONFIG_EXTCON)		+= extcon_class.o
 obj-$(CONFIG_EXTCON_GPIO)	+= extcon_gpio.o
 obj-$(CONFIG_EXTCON_MAX8997)	+= extcon-max8997.o
+obj-$(CONFIG_EXTCON_ARIZONA)	+= extcon-arizona.o