Input: wacom - register an ac power supply for wireless devices

This is used by HID Bluetooth devices but also add some more information
to the USB Wireless Receiver.
We are just porting the bits from hid-wacom.c to the common driver here.
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: Przemo Firszt <przemo@firszt.eu>
Acked-by: Ping Cheng <pingc@wacom.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

drivers/hid/wacom.h

@@ -120,6 +120,7 @@ struct wacom {
 	} led;
 	bool led_initialized;
 	struct power_supply battery;
+	struct power_supply ac;
 };
 
 static inline void wacom_schedule_work(struct wacom_wac *wacom_wac)

drivers/hid/wacom_sys.c

@@ -774,6 +774,12 @@ static enum power_supply_property wacom_battery_props[] = {
 	POWER_SUPPLY_PROP_CAPACITY
 };
 
+static enum power_supply_property wacom_ac_props[] = {
+	POWER_SUPPLY_PROP_PRESENT,
+	POWER_SUPPLY_PROP_ONLINE,
+	POWER_SUPPLY_PROP_SCOPE,
+};
+
 static int wacom_battery_get_property(struct power_supply *psy,
 				      enum power_supply_property psp,
 				      union power_supply_propval *val)
@@ -806,14 +812,38 @@ static int wacom_battery_get_property(struct power_supply *psy,
 	return ret;
 }
 
+static int wacom_ac_get_property(struct power_supply *psy,
+				enum power_supply_property psp,
+				union power_supply_propval *val)
+{
+	struct wacom *wacom = container_of(psy, struct wacom, ac);
+	int ret = 0;
+
+	switch (psp) {
+	case POWER_SUPPLY_PROP_PRESENT:
+		/* fall through */
+	case POWER_SUPPLY_PROP_ONLINE:
+		val->intval = wacom->wacom_wac.ps_connected;
+		break;
+	case POWER_SUPPLY_PROP_SCOPE:
+		val->intval = POWER_SUPPLY_SCOPE_DEVICE;
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+	return ret;
+}
+
 static int wacom_initialize_battery(struct wacom *wacom)
 {
-	int error = 0;
 	static atomic_t battery_no = ATOMIC_INIT(0);
+	int error;
 	unsigned long n;
 
 	if (wacom->wacom_wac.features.quirks & WACOM_QUIRK_BATTERY) {
 		n = atomic_inc_return(&battery_no) - 1;
+
 		wacom->battery.properties = wacom_battery_props;
 		wacom->battery.num_properties = ARRAY_SIZE(wacom_battery_props);
 		wacom->battery.get_property = wacom_battery_get_property;
@@ -822,15 +852,31 @@ static int wacom_initialize_battery(struct wacom *wacom)
 		wacom->battery.type = POWER_SUPPLY_TYPE_BATTERY;
 		wacom->battery.use_for_apm = 0;
 
+		wacom->ac.properties = wacom_ac_props;
+		wacom->ac.num_properties = ARRAY_SIZE(wacom_ac_props);
+		wacom->ac.get_property = wacom_ac_get_property;
+		sprintf(wacom->wacom_wac.ac_name, "wacom_ac_%ld", n);
+		wacom->ac.name = wacom->wacom_wac.ac_name;
+		wacom->ac.type = POWER_SUPPLY_TYPE_MAINS;
+		wacom->ac.use_for_apm = 0;
+
 		error = power_supply_register(&wacom->hdev->dev,
 					      &wacom->battery);
+		if (error)
+			return error;
+
+		power_supply_powers(&wacom->battery, &wacom->hdev->dev);
+
+		error = power_supply_register(&wacom->hdev->dev, &wacom->ac);
+		if (error) {
+			power_supply_unregister(&wacom->battery);
+			return error;
+		}
 
-		if (!error)
-			power_supply_powers(&wacom->battery,
-					    &wacom->hdev->dev);
+		power_supply_powers(&wacom->ac, &wacom->hdev->dev);
 	}
 
-	return error;
+	return 0;
 }
 
 static void wacom_destroy_battery(struct wacom *wacom)
@@ -839,6 +885,8 @@ static void wacom_destroy_battery(struct wacom *wacom)
 	     wacom->battery.dev) {
 		power_supply_unregister(&wacom->battery);
 		wacom->battery.dev = NULL;
+		power_supply_unregister(&wacom->ac);
+		wacom->ac.dev = NULL;
 	}
 }
 

drivers/hid/wacom_wac.h

@@ -155,6 +155,7 @@ struct wacom_wac {
 	char name[WACOM_NAME_MAX];
 	char pad_name[WACOM_NAME_MAX];
 	char bat_name[WACOM_NAME_MAX];
+	char ac_name[WACOM_NAME_MAX];
 	unsigned char data[WACOM_PKGLEN_MAX];
 	int tool[2];
 	int id[2];