charger-manager: Set current limit of regulator for over current protection

This patch support the protection of host device from over current.
The Charger-manager set proper current limit of charger(regulator) for
charging according to type of charger cable when external connector
is attached.

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Myungjoo Ham <myungjoo.ham@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org>

drivers/power/charger-manager.c

@@ -1001,6 +1001,21 @@ static void charger_extcon_work(struct work_struct *work)
 {
 	struct charger_cable *cable =
 			container_of(work, struct charger_cable, wq);
+	int ret;
+
+	if (cable->attached && cable->min_uA != 0 && cable->max_uA != 0) {
+		ret = regulator_set_current_limit(cable->charger->consumer,
+					cable->min_uA, cable->max_uA);
+		if (ret < 0) {
+			pr_err("Cannot set current limit of %s (%s)\n",
+				cable->charger->regulator_name, cable->name);
+			return;
+		}
+
+		pr_info("Set current limit of %s : %duA ~ %duA\n",
+					cable->charger->regulator_name,
+					cable->min_uA, cable->max_uA);
+	}
 
 	try_charger_enable(cable->cm, cable->attached);
 }

include/linux/power/charger-manager.h

@@ -94,6 +94,14 @@ struct charger_cable {
 	bool attached;
 
 	struct charger_regulator *charger;
+
+	/*
+	 * Set min/max current of regulator to protect over-current issue
+	 * according to a kind of charger cable when cable is attached.
+	 */
+	int min_uA;
+	int max_uA;
+
 	struct charger_manager *cm;
 };