extcon: axp288: Add axp288 extcon driver support

This patch adds the extcon support for AXP288 PMIC which
has the BC1.2 charger detection capability. Additionally
it also adds the USB mux switching support b/w SOC and PMIC
based on GPIO control.

Signed-off-by: Ramakrishna Pallala <ramakrishna.pallala@intel.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
[cw00.choi: Modify the log message to keep the consistent log message pattern]
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig
index bd10b6c..b74e1f2 100644
--- a/drivers/extcon/Kconfig
+++ b/drivers/extcon/Kconfig
@@ -28,6 +28,13 @@
 	  with Wolfson Arizona devices. These are audio CODECs with
 	  advanced audio accessory detection support.
 
+config EXTCON_AXP288
+	tristate "X-Power AXP288 EXTCON support"
+	depends on MFD_AXP20X && USB_PHY
+	help
+	  Say Y here to enable support for USB peripheral detection
+	  and USB MUX switching by X-Power AXP288 PMIC.
+
 config EXTCON_GPIO
 	tristate "GPIO extcon support"
 	depends on GPIOLIB