driver: act8865: Add suspending ACT8945A charger

Setting the SUSCHG bit of APCH register 0x71 to suspend
charging, so that the PMIC charger function is systematically
disabled after boot.

This function is disabled by default, you can enable it by
make menuconfig.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>

Config.in

@@ -332,6 +332,14 @@ config CONFIG_DISABLE_ACT8865_I2C
 	  There are some issue about active-semi ACT8865's I2C interface,
 	  which affects the other chip which stands on the same I2C bus, such as MXT touchscreen.
 
+config CONFIG_SUSPEND_ACT8945A_CHARGER
+	bool "Suspend ACT8945A Charger"
+	select CONFIG_ACT8865
+	default n
+	help
+	  This interface let you to suspend the ACT8945A charger
+	  function after boot.
+
 endmenu
 
 config CONFIG_ACT8865

driver/act8865.c

@@ -291,3 +291,63 @@ void act8865_workaround(void)
 #endif
 }
 #endif
+
+/**
+ * ACT8945A Charger Registers Map
+ */
+/* 0x70: Reserved */
+#define ACT8945A_APCH_CFG		0x71
+#define ACT8945A_APCH_STATUS		0x78
+#define ACT8945A_APCH_CTRL		0x79
+#define ACT8945A_APCH_STATE		0x7A
+
+/* ACT8945A_APCH_CFG */
+#define APCH_CFG_OVPSET			(0x3 << 0)
+#define APCH_CFG_PRETIMO		(0x3 << 2)
+#define APCH_CFG_TOTTIMO		(0x3 << 4)
+#define APCH_CFG_SUSCHG			(0x1 << 7)
+
+/* ACT8945A_APCH_STATE */
+#define APCH_STATE_ACINSTAT		(0x1 << 1)
+#define APCH_STATE_CSTATE		(0x3 << 4)
+#define APCH_STATE_CSTATE_SHIFT		4
+#define APCH_STATE_CSTATE_DISABLED	0x00
+#define APCH_STATE_CSTATE_EOC		0x01
+#define APCH_STATE_CSTATE_FAST		0x02
+#define APCH_STATE_CSTATE_PRE		0x03
+
+#ifdef CONFIG_SUSPEND_ACT8945A_CHARGER
+int act8945a_suspend_charger(void)
+{
+	unsigned char data;
+	int ret;
+
+	if (!twi_init_done)
+		twi_init();
+
+	ret = act8865_read(ACT8945A_APCH_CFG, &data);
+	if (ret)
+		return -1;
+
+	data |= APCH_CFG_SUSCHG;
+	ret = act8865_write(ACT8945A_APCH_CFG, data);
+	if (ret)
+		return -1;
+
+	ret = act8865_read(ACT8945A_APCH_STATE, &data);
+	if (ret)
+		return -1;
+
+	if ((data & APCH_STATE_CSTATE) != APCH_STATE_CSTATE_DISABLED) {
+		dbg_loud("ACT8945A: Failed to suspend charger\n");
+		return -1;
+	}
+
+	return 0;
+}
+#else
+int act8945a_suspend_charger(void)
+{
+	return 0;
+}
+#endif

driver/driver_cpp.mk

@@ -229,6 +229,10 @@ ifeq ($(CONFIG_DISABLE_ACT8865_I2C), y)
 CPPFLAGS += -DCONFIG_DISABLE_ACT8865_I2C
 endif
 
+ifeq ($(CONFIG_SUSPEND_ACT8945A_CHARGER), y)
+CPPFLAGS += -DCONFIG_SUSPEND_ACT8945A_CHARGER
+endif
+
 ifeq ($(CONFIG_PM), y)
 CPPFLAGS += -DCONFIG_PM
 endif

include/act8865.h

@@ -108,5 +108,6 @@ extern int act8865_check_i2c_disabled(void);
 
 extern int act8865_set_power_saving_mode(void);
 extern void act8865_workaround(void);
+extern int act8945a_suspend_charger(void);
 
 #endif

main.c

@@ -78,6 +78,8 @@ int main(void)
 
 #ifdef CONFIG_ACT8865
 	act8865_workaround();
+
+	act8945a_suspend_charger();
 #endif
 
 	init_load_image(&image);