[PATCH v2 1/4] HID: wiimote: turn on the LEDs indicating the controller id

[Rafael Passos <rafael@rcpassos.me>]

The behavior in a Wii/Wii U console is to have each controller turn on
a different LED indicating the controller id.
This commit implements the same behavior using the ida struct.
Unlike switch controllers, each ID only turns one LED (from 1 to 4).

Signed-off-by: Rafael Passos <rafael@rcpassos.me>
---
 drivers/hid/hid-wiimote-core.c | 54 ++++++++++++++++++++++++++++++----
 drivers/hid/hid-wiimote.h      |  1 +
 2 files changed, 49 insertions(+), 6 deletions(-)

diff --git a/drivers/hid/hid-wiimote-core.c b/drivers/hid/hid-wiimote-core.c
index 63c4fa8fbb9b..91c2cec35f6e 100644
--- a/drivers/hid/hid-wiimote-core.c
+++ b/drivers/hid/hid-wiimote-core.c
@@ -621,6 +621,13 @@ static const __u8 * const wiimote_devtype_mods[WIIMOTE_DEV_NUM] = {
 	},
 };
 
+static const __u8 player_leds[] = {
+	WIIPROTO_FLAG_LED1,
+	WIIPROTO_FLAG_LED2,
+	WIIPROTO_FLAG_LED3,
+	WIIPROTO_FLAG_LED4
+};
+
 static void wiimote_modules_load(struct wiimote_data *wdata,
 				 unsigned int devtype)
 {
@@ -671,6 +678,12 @@ static void wiimote_modules_load(struct wiimote_data *wdata,
 	spin_lock_irq(&wdata->state.lock);
 	wdata->state.devtype = devtype;
 	spin_unlock_irq(&wdata->state.lock);
+
+	/* after loading all modules, set the LED for the player ID cycling from 1 to 4*/
+	scoped_guard(spinlock_irqsave, &wdata->state.lock) {
+		wiiproto_req_leds(wdata, player_leds[(wdata->player_id - 1) % 4]);
+	}
+
 	return;
 
 error:
@@ -855,11 +868,11 @@ static void wiimote_init_set_type(struct wiimote_data *wdata,
 
 done:
 	if (devtype == WIIMOTE_DEV_GENERIC)
-		hid_info(wdata->hdev, "cannot detect device; NAME: %s VID: %04x PID: %04x EXT: %04x\n",
-			name, vendor, product, exttype);
+		hid_info(wdata->hdev, "cannot detect device; NAME: %s VID: %04x PID: %04x EXT: %04x (%d)\n",
+			name, vendor, product, exttype, wdata->player_id);
 	else
-		hid_info(wdata->hdev, "detected device: %s\n",
-			 wiimote_devtype_names[devtype]);
+		hid_info(wdata->hdev, "detected device: %s (%d)\n",
+			 wiimote_devtype_names[devtype], wdata->player_id);
 
 	wiimote_modules_load(wdata, devtype);
 }
@@ -1786,11 +1799,15 @@ static void wiimote_destroy(struct wiimote_data *wdata)
 	kfree(wdata);
 }
 
+/* Global id allocator for wii remotes */
+static DEFINE_IDA(wiimote_ida);
+
 static int wiimote_hid_probe(struct hid_device *hdev,
 				const struct hid_device_id *id)
 {
 	struct wiimote_data *wdata;
 	int ret;
+	int player_id;
 
 	hdev->quirks |= HID_QUIRK_NO_INIT_REPORTS;
 
@@ -1834,7 +1851,16 @@ static int wiimote_hid_probe(struct hid_device *hdev,
 	if (ret)
 		goto err_free;
 
-	hid_info(hdev, "New device registered\n");
+	player_id = ida_alloc_min(&wiimote_ida, 1, GFP_KERNEL);
+	if (player_id < 1) {
+		hid_err(hdev, "cannot allocate controller id\n");
+		ret = player_id;
+		goto err_free;
+	}
+
+	wdata->player_id = player_id;
+
+	hid_info(hdev, "New device registered (Wiimote %d)\n", player_id);
 
 	/* schedule device detection */
 	wiimote_schedule(wdata);
@@ -1862,6 +1888,8 @@ static void wiimote_hid_remove(struct hid_device *hdev)
 {
 	struct wiimote_data *wdata = hid_get_drvdata(hdev);
 
+	ida_free(&wiimote_ida, wdata->player_id);
+
 	hid_info(hdev, "Device removed\n");
 	wiimote_destroy(wdata);
 }
@@ -1887,7 +1915,21 @@ static struct hid_driver wiimote_hid_driver = {
 	.remove = wiimote_hid_remove,
 	.raw_event = wiimote_hid_event,
 };
-module_hid_driver(wiimote_hid_driver);
+
+
+static int __init wiimote_init(void)
+{
+	return hid_register_driver(&wiimote_hid_driver);
+}
+
+static void __exit wiimote_exit(void)
+{
+	hid_unregister_driver(&wiimote_hid_driver);
+	ida_destroy(&wiimote_ida);
+}
+
+module_init(wiimote_init);
+module_exit(wiimote_exit);
 
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("David Herrmann <dh.herrmann@gmail.com>");
diff --git a/drivers/hid/hid-wiimote.h b/drivers/hid/hid-wiimote.h
index 9c12f63f6dd2..a53f72d5077e 100644
--- a/drivers/hid/hid-wiimote.h
+++ b/drivers/hid/hid-wiimote.h
@@ -153,6 +153,7 @@ struct wiimote_data {
 	struct input_dev *mp;
 	struct timer_list timer;
 	struct wiimote_debug *debug;
+	__u8 player_id;
 
 	union {
 		struct input_dev *input;
-- 
2.53.0