extcon: int3496: Add Intel INT3496 ACPI device extcon driver

Add an extcon driver for USB OTG ports controlled by an Intel INT3496
ACPI device (e.g. Baytrail, Cherrytrail devices).

Signed-off-by: David Cohen <david.a.cohen@intel.com>
[hdgoede@redhat.com: Port to current kernel, cleanup, submit upstream]
[hdgoede@redhat.com: Add Documentation/extcon/intel-int3496.txt]
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig
index 04788d9..96bbae5 100644
--- a/drivers/extcon/Kconfig
+++ b/drivers/extcon/Kconfig
@@ -42,6 +42,16 @@
 	  Say Y here to enable GPIO based extcon support. Note that GPIO
 	  extcon supports single state per extcon instance.
 
+config EXTCON_INTEL_INT3496
+	tristate "Intel INT3496 ACPI device extcon driver"
+	depends on GPIOLIB && ACPI
+	help
+	  Say Y here to enable extcon support for USB OTG ports controlled by
+	  an Intel INT3496 ACPI device.
+
+	  This ACPI device is typically found on Intel Baytrail or Cherrytrail
+	  based tablets, or other Baytrail / Cherrytrail devices.
+
 config EXTCON_MAX14577
 	tristate "Maxim MAX14577/77836 EXTCON Support"
 	depends on MFD_MAX14577