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>

drivers/extcon/Kconfig

@@ -28,6 +28,13 @@ config EXTCON_ARIZONA
 	  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

drivers/extcon/Makefile

@@ -5,6 +5,7 @@
 obj-$(CONFIG_EXTCON)		+= extcon.o
 obj-$(CONFIG_EXTCON_ADC_JACK)	+= extcon-adc-jack.o
 obj-$(CONFIG_EXTCON_ARIZONA)	+= extcon-arizona.o
+obj-$(CONFIG_EXTCON_AXP288)	+= extcon-axp288.o
 obj-$(CONFIG_EXTCON_GPIO)	+= extcon-gpio.o
 obj-$(CONFIG_EXTCON_MAX14577)	+= extcon-max14577.o
 obj-$(CONFIG_EXTCON_MAX77693)	+= extcon-max77693.o

include/linux/mfd/axp20x.h

@@ -275,4 +275,9 @@ struct axp20x_fg_pdata {
 	int thermistor_curve[MAX_THERM_CURVE_SIZE][2];
 };
 
+struct axp288_extcon_pdata {
+	/* GPIO pin control to switch D+/D- lines b/w PMIC and SOC */
+	struct gpio_desc *gpio_mux_cntl;
+};
+
 #endif /* __LINUX_MFD_AXP20X_H */