HID: wacom: generic: Set battery quirk only when we see battery data

Some devices will include battery status usages in the HID descriptor
but we won't see that battery data for one reason or another. For example,
AES sensors won't send battery data unless an AES pen is in proximity.
If a user does not have an AES pen but instead only interacts with the
AES touchscreen with their fingers then there is no need for us to create
a battery object. Similarly, if a family of peripherals shares the same
HID descriptor between wired-only and wireless-capable SKUs, users of the
former may never see a battery event and will not want a power_supply
object created.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=217062
Link: https://gitlab.gnome.org/GNOME/gnome-control-center/-/issues/2354
Signed-off-by: Jason Gerecke <[email protected]>
Tested-by: Mario Limonciello <[email protected]>
Signed-off-by: Jiri Kosina <[email protected]>
[[email protected]: Imported into input-wacom (bea407a427ba)]
Signed-off-by: Jason Gerecke <[email protected]>

Author: jigpu

4.5/wacom_wac.c

@@ -1991,18 +1991,7 @@ static void wacom_map_usage(struct input_dev *input, struct hid_usage *usage,
 static void wacom_wac_battery_usage_mapping(struct hid_device *hdev,
 		struct hid_field *field, struct hid_usage *usage)
 {
-	struct wacom *wacom = hid_get_drvdata(hdev);
-	struct wacom_wac *wacom_wac = &wacom->wacom_wac;
-	struct wacom_features *features = &wacom_wac->features;
-	unsigned equivalent_usage = wacom_equivalent_usage(usage->hid);
-
-	switch (equivalent_usage) {
-	case HID_DG_BATTERYSTRENGTH:
-	case WACOM_HID_WD_BATTERY_LEVEL:
-	case WACOM_HID_WD_BATTERY_CHARGING:
-		features->quirks |= WACOM_QUIRK_BATTERY;
-		break;
-	}
+	return;
 }
 
 static void wacom_wac_battery_event(struct hid_device *hdev, struct hid_field *field,
@@ -2023,18 +2012,21 @@ static void wacom_wac_battery_event(struct hid_device *hdev, struct hid_field *f
 			wacom_wac->hid_data.bat_connected = 1;
 			wacom_wac->hid_data.bat_status = WACOM_POWER_SUPPLY_STATUS_AUTO;
 		}
+		wacom_wac->features.quirks |= WACOM_QUIRK_BATTERY;
 		break;
 	case WACOM_HID_WD_BATTERY_LEVEL:
 		value = value * 100 / (field->logical_maximum - field->logical_minimum);
 		wacom_wac->hid_data.battery_capacity = value;
 		wacom_wac->hid_data.bat_connected = 1;
 		wacom_wac->hid_data.bat_status = WACOM_POWER_SUPPLY_STATUS_AUTO;
+		wacom_wac->features.quirks |= WACOM_QUIRK_BATTERY;
 		break;
 	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;
 		wacom_wac->hid_data.bat_status = WACOM_POWER_SUPPLY_STATUS_AUTO;
+		wacom_wac->features.quirks |= WACOM_QUIRK_BATTERY;
 		break;
 	}
 }
@@ -2050,18 +2042,15 @@ static void wacom_wac_battery_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;
 
-	if (features->quirks & WACOM_QUIRK_BATTERY) {
-		int status = wacom_wac->hid_data.bat_status;
-		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;
+	int status = wacom_wac->hid_data.bat_status;
+	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, status, capacity, charging,
-				     connected, powered);
-	}
+	wacom_notify_battery(wacom_wac, status, capacity, charging,
+			     connected, powered);
 }
 
 static void wacom_wac_pad_usage_mapping(struct hid_device *hdev,