HID: wacom: generic: Add support for battery status on pen and pad interfaces

Adds support for usages that may appear on the pen or pad interface which
report the state of the tablet battery.
Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

drivers/hid/wacom_wac.c

@@ -1525,6 +1525,10 @@ static void wacom_wac_pad_usage_mapping(struct hid_device *hdev,
 	unsigned equivalent_usage = wacom_equivalent_usage(usage->hid);
 
 	switch (equivalent_usage) {
+	case WACOM_HID_WD_BATTERY_LEVEL:
+	case WACOM_HID_WD_BATTERY_CHARGING:
+		features->quirks |= WACOM_QUIRK_BATTERY;
+		break;
 	case WACOM_HID_WD_ACCELEROMETER_X:
 		__set_bit(INPUT_PROP_ACCELEROMETER, input->propbit);
 		wacom_map_usage(input, usage, field, EV_ABS, ABS_X, 0);
@@ -1574,8 +1578,25 @@ static int wacom_wac_pad_event(struct hid_device *hdev, struct hid_field *field,
 		wacom_wac->hid_data.inrange_state |= value;
 	}
 
-	if (equivalent_usage != WACOM_HID_WD_TOUCHRINGSTATUS)
+	switch (equivalent_usage) {
+	case WACOM_HID_WD_BATTERY_LEVEL:
+		wacom_wac->hid_data.battery_capacity = value;
+		wacom_wac->hid_data.bat_connected = 1;
+		return 0;
+
+	case WACOM_HID_WD_BATTERY_CHARGING:
+		wacom_wac->hid_data.bat_charging = value;
+		wacom_wac->hid_data.ps_connected = value;
+		wacom_wac->hid_data.bat_connected = 1;
+		return 0;
+
+	case WACOM_HID_WD_TOUCHRINGSTATUS:
+		return 0;
+
+	default:
 		input_event(input, usage->type, usage->code, value);
+		break;
+	}
 
 	return 0;
 }
@@ -1594,6 +1615,7 @@ static void wacom_wac_pad_report(struct hid_device *hdev,
 {
 	struct wacom *wacom = hid_get_drvdata(hdev);
 	struct wacom_wac *wacom_wac = &wacom->wacom_wac;
+	struct wacom_features *features = &wacom_wac->features;
 	struct input_dev *input = wacom_wac->pad_input;
 	bool active = wacom_wac->hid_data.inrange_state != 0;
 
@@ -1604,6 +1626,16 @@ static void wacom_wac_pad_report(struct hid_device *hdev,
 	if (wacom_equivalent_usage(report->field[0]->physical) == HID_DG_TABLETFUNCTIONKEY)
 		input_event(input, EV_ABS, ABS_MISC, active ? PAD_DEVICE_ID : 0);
 
+	if (features->quirks & WACOM_QUIRK_BATTERY) {
+		int capacity = wacom_wac->hid_data.battery_capacity;
+		bool charging = wacom_wac->hid_data.bat_charging;
+		bool connected = wacom_wac->hid_data.bat_connected;
+		bool powered = wacom_wac->hid_data.ps_connected;
+
+		wacom_notify_battery(wacom_wac, capacity, charging,
+				     connected, powered);
+	}
+
 	input_sync(input);
 }
 
@@ -1633,6 +1665,9 @@ static void wacom_wac_pen_usage_mapping(struct hid_device *hdev,
 	case HID_DG_INRANGE:
 		wacom_map_usage(input, usage, field, EV_KEY, BTN_TOOL_PEN, 0);
 		break;
+	case HID_DG_BATTERYSTRENGTH:
+		features->quirks |= WACOM_QUIRK_BATTERY;
+		break;
 	case HID_DG_INVERT:
 		wacom_map_usage(input, usage, field, EV_KEY,
 				BTN_TOOL_RUBBER, 0);
@@ -1703,6 +1738,10 @@ static int wacom_wac_pen_event(struct hid_device *hdev, struct hid_field *field,
 		if (!(features->quirks & WACOM_QUIRK_SENSE))
 			wacom_wac->hid_data.sense_state = value;
 		return 0;
+	case HID_DG_BATTERYSTRENGTH:
+		wacom_wac->hid_data.battery_capacity = value;
+		wacom_wac->hid_data.bat_connected = 1;
+		break;
 	case HID_DG_INVERT:
 		wacom_wac->hid_data.invert_state = value;
 		return 0;

drivers/hid/wacom_wac.h

@@ -101,6 +101,8 @@
 #define WACOM_HID_WD_ACCELEROMETER_X    (WACOM_HID_UP_WACOMDIGITIZER | 0x0401)
 #define WACOM_HID_WD_ACCELEROMETER_Y    (WACOM_HID_UP_WACOMDIGITIZER | 0x0402)
 #define WACOM_HID_WD_ACCELEROMETER_Z    (WACOM_HID_UP_WACOMDIGITIZER | 0x0403)
+#define WACOM_HID_WD_BATTERY_CHARGING   (WACOM_HID_UP_WACOMDIGITIZER | 0x0404)
+#define WACOM_HID_WD_BATTERY_LEVEL      (WACOM_HID_UP_WACOMDIGITIZER | 0x043b)
 #define WACOM_HID_WD_EXPRESSKEY00       (WACOM_HID_UP_WACOMDIGITIZER | 0x0910)
 #define WACOM_HID_WD_BUTTONHOME         (WACOM_HID_UP_WACOMDIGITIZER | 0x0990)
 #define WACOM_HID_WD_BUTTONUP           (WACOM_HID_UP_WACOMDIGITIZER | 0x0991)
@@ -257,6 +259,10 @@ struct hid_data {
 	int last_slot_field;
 	int num_expected;
 	int num_received;
+	int battery_capacity;
+	int bat_charging;
+	int bat_connected;
+	int ps_connected;
 };
 
 struct wacom_remote_data {

include/linux/hid.h

@@ -231,6 +231,7 @@ struct hid_item {
 #define HID_DG_TAP		0x000d0035
 #define HID_DG_TABLETFUNCTIONKEY	0x000d0039
 #define HID_DG_PROGRAMCHANGEKEY	0x000d003a
+#define HID_DG_BATTERYSTRENGTH	0x000d003b
 #define HID_DG_INVERT		0x000d003c
 #define HID_DG_TILT_X		0x000d003d
 #define HID_DG_TILT_Y		0x000d003e