HID: wiimote: add device detection

Nintendo produced many different devices that are internally based on the
Wii Remote protocol but provide different peripherals. To support these
devices, we need to schedule a device detection during initialization.

Device detection includes requesting a status report, reading extension
information and then evaluating which device we may be dealing with.

We currently detect gen1 and gen2 Wii Remote devices. All other devices
are marked as generic devices. More detections will be added later.

In followup patches we will be using these device IDs to control which
peripherals to initialize. For instance if a device is known to have no IR
camera, there is no need to provide the IR input device nor trying to
access IR registers. In fact, there are 3rd party devices that break if we
try things like this (hurray!).

The init_worker will be scheduled whenever we get hotplug events. This
isn't implemented, yet and will be added later. However, we need to make
sure that this worker can be called multiple times.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/hid/hid-wiimote.h b/drivers/hid/hid-wiimote.h
index 2700d47..301607d 100644
--- a/drivers/hid/hid-wiimote.h
+++ b/drivers/hid/hid-wiimote.h
@@ -35,6 +35,8 @@
 #define WIIPROTO_FLAG_IR_BASIC		0x40
 #define WIIPROTO_FLAG_IR_EXT		0x80
 #define WIIPROTO_FLAG_IR_FULL		0xc0 /* IR_BASIC | IR_EXT */
+#define WIIPROTO_FLAG_EXT_PLUGGED	0x0100
+
 #define WIIPROTO_FLAGS_LEDS (WIIPROTO_FLAG_LED1 | WIIPROTO_FLAG_LED2 | \
 					WIIPROTO_FLAG_LED3 | WIIPROTO_FLAG_LED4)
 #define WIIPROTO_FLAGS_IR (WIIPROTO_FLAG_IR_BASIC | WIIPROTO_FLAG_IR_EXT | \
@@ -43,6 +45,21 @@
 /* return flag for led \num */
 #define WIIPROTO_FLAG_LED(num) (WIIPROTO_FLAG_LED1 << (num - 1))
 
+enum wiimote_devtype {
+	WIIMOTE_DEV_PENDING,
+	WIIMOTE_DEV_UNKNOWN,
+	WIIMOTE_DEV_GENERIC,
+	WIIMOTE_DEV_GEN10,
+	WIIMOTE_DEV_GEN20,
+	WIIMOTE_DEV_NUM,
+};
+
+enum wiimote_exttype {
+	WIIMOTE_EXT_NONE,
+	WIIMOTE_EXT_UNKNOWN,
+	WIIMOTE_EXT_NUM,
+};
+
 struct wiimote_buf {
 	__u8 data[HID_MAX_BUFFER_SIZE];
 	size_t size;
@@ -58,9 +75,10 @@
 
 struct wiimote_state {
 	spinlock_t lock;
-	__u8 flags;
+	__u32 flags;
 	__u8 accel_split[2];
 	__u8 drm;
+	__u8 devtype;
 
 	/* synchronous cmd requests */
 	struct mutex sync;
@@ -87,6 +105,7 @@
 
 	struct wiimote_queue queue;
 	struct wiimote_state state;
+	struct work_struct init_worker;
 };
 
 enum wiiproto_reqs {
@@ -181,6 +200,11 @@
 	return mutex_lock_interruptible(&wdata->state.sync) ? -ERESTARTSYS : 0;
 }
 
+static inline void wiimote_cmd_acquire_noint(struct wiimote_data *wdata)
+{
+	mutex_lock(&wdata->state.sync);
+}
+
 /* requires the state.lock spinlock to be held */
 static inline void wiimote_cmd_set(struct wiimote_data *wdata, int cmd,
 								__u32 opt)
@@ -208,4 +232,15 @@
 		return 0;
 }
 
+static inline int wiimote_cmd_wait_noint(struct wiimote_data *wdata)
+{
+	unsigned long ret;
+
+	ret = wait_for_completion_timeout(&wdata->state.ready, HZ);
+	if (!ret)
+		return -EIO;
+	else
+		return 0;
+}
+
 #endif