HID: playstation: add DualSense battery support.

Report DualSense battery status information through power_supply class.
Signed-off-by: Roderick Colenbrander <roderick.colenbrander@sony.com>
Reviewed-by: Barnabás Pőcze <pobrn@protonmail.com>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>

drivers/hid/Kconfig

@@ -856,6 +856,7 @@ config HID_PLANTRONICS
 config HID_PLAYSTATION
 	tristate "PlayStation HID Driver"
 	depends on HID
+	select POWER_SUPPLY
 	help
 	  Provides support for Sony PS5 controllers including support for
 	  its special functionalities e.g. touchpad, lights and motion

drivers/hid/hid-playstation.c

@@ -20,6 +20,13 @@
 /* Base class for playstation devices. */
 struct ps_device {
 	struct hid_device *hdev;
+	spinlock_t lock;
+
+	struct power_supply_desc battery_desc;
+	struct power_supply *battery;
+	uint8_t battery_capacity;
+	int battery_status;
+
 	uint8_t mac_address[6]; /* Note: stored in little endian order. */
 
 	int (*parse_report)(struct ps_device *dev, struct hid_report *report, u8 *data, int size);
@@ -48,6 +55,11 @@ struct ps_device {
 #define DS_BUTTONS2_PS_HOME	BIT(0)
 #define DS_BUTTONS2_TOUCHPAD	BIT(1)
 
+/* Status field of DualSense input report. */
+#define DS_STATUS_BATTERY_CAPACITY	GENMASK(3, 0)
+#define DS_STATUS_CHARGING		GENMASK(7, 4)
+#define DS_STATUS_CHARGING_SHIFT	4
+
 struct dualsense {
 	struct ps_device base;
 	struct input_dev *gamepad;
@@ -140,6 +152,81 @@ static struct input_dev *ps_allocate_input_dev(struct hid_device *hdev, const ch
 	return input_dev;
 }
 
+static enum power_supply_property ps_power_supply_props[] = {
+	POWER_SUPPLY_PROP_STATUS,
+	POWER_SUPPLY_PROP_PRESENT,
+	POWER_SUPPLY_PROP_CAPACITY,
+	POWER_SUPPLY_PROP_SCOPE,
+};
+
+static int ps_battery_get_property(struct power_supply *psy,
+		enum power_supply_property psp,
+		union power_supply_propval *val)
+{
+	struct ps_device *dev = power_supply_get_drvdata(psy);
+	uint8_t battery_capacity;
+	int battery_status;
+	unsigned long flags;
+	int ret;
+
+	spin_lock_irqsave(&dev->lock, flags);
+	battery_capacity = dev->battery_capacity;
+	battery_status = dev->battery_status;
+	spin_unlock_irqrestore(&dev->lock, flags);
+
+	switch (psp) {
+	case POWER_SUPPLY_PROP_STATUS:
+		val->intval = battery_status;
+		break;
+	case POWER_SUPPLY_PROP_PRESENT:
+		val->intval = 1;
+		break;
+	case POWER_SUPPLY_PROP_CAPACITY:
+		val->intval = battery_capacity;
+		break;
+	case POWER_SUPPLY_PROP_SCOPE:
+		val->intval = POWER_SUPPLY_SCOPE_DEVICE;
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	return 0;
+}
+
+static int ps_device_register_battery(struct ps_device *dev)
+{
+	struct power_supply *battery;
+	struct power_supply_config battery_cfg = { .drv_data = dev };
+	int ret;
+
+	dev->battery_desc.type = POWER_SUPPLY_TYPE_BATTERY;
+	dev->battery_desc.properties = ps_power_supply_props;
+	dev->battery_desc.num_properties = ARRAY_SIZE(ps_power_supply_props);
+	dev->battery_desc.get_property = ps_battery_get_property;
+	dev->battery_desc.name = devm_kasprintf(&dev->hdev->dev, GFP_KERNEL,
+			"ps-controller-battery-%pMR", dev->mac_address);
+	if (!dev->battery_desc.name)
+		return -ENOMEM;
+
+	battery = devm_power_supply_register(&dev->hdev->dev, &dev->battery_desc, &battery_cfg);
+	if (IS_ERR(battery)) {
+		ret = PTR_ERR(battery);
+		hid_err(dev->hdev, "Unable to register battery device: %d\n", ret);
+		return ret;
+	}
+	dev->battery = battery;
+
+	ret = power_supply_powers(dev->battery, &dev->hdev->dev);
+	if (ret) {
+		hid_err(dev->hdev, "Unable to activate battery device: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
 static struct input_dev *ps_gamepad_create(struct hid_device *hdev)
 {
 	struct input_dev *gamepad;
@@ -223,7 +310,9 @@ static int dualsense_parse_report(struct ps_device *ps_dev, struct hid_report *r
 	struct hid_device *hdev = ps_dev->hdev;
 	struct dualsense *ds = container_of(ps_dev, struct dualsense, base);
 	struct dualsense_input_report *ds_report;
-	uint8_t value;
+	uint8_t battery_data, battery_capacity, charging_status, value;
+	int battery_status;
+	unsigned long flags;
 
 	/*
 	 * DualSense in USB uses the full HID report for reportID 1, but
@@ -266,12 +355,49 @@ static int dualsense_parse_report(struct ps_device *ps_dev, struct hid_report *r
 	input_report_key(ds->gamepad, BTN_MODE,   ds_report->buttons[2] & DS_BUTTONS2_PS_HOME);
 	input_sync(ds->gamepad);
 
+	battery_data = ds_report->status & DS_STATUS_BATTERY_CAPACITY;
+	charging_status = (ds_report->status & DS_STATUS_CHARGING) >> DS_STATUS_CHARGING_SHIFT;
+
+	switch (charging_status) {
+	case 0x0:
+		/*
+		 * Each unit of battery data corresponds to 10%
+		 * 0 = 0-9%, 1 = 10-19%, .. and 10 = 100%
+		 */
+		battery_capacity = min(battery_data * 10 + 5, 100);
+		battery_status = POWER_SUPPLY_STATUS_DISCHARGING;
+		break;
+	case 0x1:
+		battery_capacity = min(battery_data * 10 + 5, 100);
+		battery_status = POWER_SUPPLY_STATUS_CHARGING;
+		break;
+	case 0x2:
+		battery_capacity = 100;
+		battery_status = POWER_SUPPLY_STATUS_FULL;
+		break;
+	case 0xa: /* voltage or temperature out of range */
+	case 0xb: /* temperature error */
+		battery_capacity = 0;
+		battery_status = POWER_SUPPLY_STATUS_NOT_CHARGING;
+		break;
+	case 0xf: /* charging error */
+	default:
+		battery_capacity = 0;
+		battery_status = POWER_SUPPLY_STATUS_UNKNOWN;
+	}
+
+	spin_lock_irqsave(&ps_dev->lock, flags);
+	ps_dev->battery_capacity = battery_capacity;
+	ps_dev->battery_status = battery_status;
+	spin_unlock_irqrestore(&ps_dev->lock, flags);
+
 	return 0;
 }
 
 static struct ps_device *dualsense_create(struct hid_device *hdev)
 {
 	struct dualsense *ds;
+	struct ps_device *ps_dev;
 	int ret;
 
 	ds = devm_kzalloc(&hdev->dev, sizeof(*ds), GFP_KERNEL);
@@ -284,8 +410,12 @@ static struct ps_device *dualsense_create(struct hid_device *hdev)
 	 */
 	hdev->version |= HID_PLAYSTATION_VERSION_PATCH;
 
-	ds->base.hdev = hdev;
-	ds->base.parse_report = dualsense_parse_report;
+	ps_dev = &ds->base;
+	ps_dev->hdev = hdev;
+	spin_lock_init(&ps_dev->lock);
+	ps_dev->battery_capacity = 100; /* initial value until parse_report. */
+	ps_dev->battery_status = POWER_SUPPLY_STATUS_UNKNOWN;
+	ps_dev->parse_report = dualsense_parse_report;
 	hid_set_drvdata(hdev, ds);
 
 	ret = dualsense_get_mac_address(ds);
@@ -301,6 +431,10 @@ static struct ps_device *dualsense_create(struct hid_device *hdev)
 		goto err;
 	}
 
+	ret = ps_device_register_battery(ps_dev);
+	if (ret)
+		goto err;
+
 	return &ds->base;
 
 err: