Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1887 insertions, 0 deletions

diff --git a/drivers/hid/hid-wiimote-core.c b/drivers/hid/hid-wiimote-core.c
new file mode 100644
index 000000000..41012681c
--- /dev/null
+++ b/drivers/hid/hid-wiimote-core.c
@@ -0,0 +1,1887 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * HID driver for Nintendo Wii / Wii U peripherals
+ * Copyright (c) 2011-2013 David Herrmann <dh.herrmann@gmail.com>
+ */
+
+/*
+ */
+
+#include <linux/completion.h>
+#include <linux/device.h>
+#include <linux/hid.h>
+#include <linux/input.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/spinlock.h>
+#include "hid-ids.h"
+#include "hid-wiimote.h"
+
+/* output queue handling */
+
+static int wiimote_hid_send(struct hid_device *hdev, __u8 *buffer,
+			    size_t count)
+{
+	__u8 *buf;
+	int ret;
+
+	if (!hdev->ll_driver->output_report)
+		return -ENODEV;
+
+	buf = kmemdup(buffer, count, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	ret = hid_hw_output_report(hdev, buf, count);
+
+	kfree(buf);
+	return ret;
+}
+
+static void wiimote_queue_worker(struct work_struct *work)
+{
+	struct wiimote_queue *queue = container_of(work, struct wiimote_queue,
+						   worker);
+	struct wiimote_data *wdata = container_of(queue, struct wiimote_data,
+						  queue);
+	unsigned long flags;
+	int ret;
+
+	spin_lock_irqsave(&wdata->queue.lock, flags);
+
+	while (wdata->queue.head != wdata->queue.tail) {
+		spin_unlock_irqrestore(&wdata->queue.lock, flags);
+		ret = wiimote_hid_send(wdata->hdev,
+				 wdata->queue.outq[wdata->queue.tail].data,
+				 wdata->queue.outq[wdata->queue.tail].size);
+		if (ret < 0) {
+			spin_lock_irqsave(&wdata->state.lock, flags);
+			wiimote_cmd_abort(wdata);
+			spin_unlock_irqrestore(&wdata->state.lock, flags);
+		}
+		spin_lock_irqsave(&wdata->queue.lock, flags);
+
+		wdata->queue.tail = (wdata->queue.tail + 1) % WIIMOTE_BUFSIZE;
+	}
+
+	spin_unlock_irqrestore(&wdata->queue.lock, flags);
+}
+
+static void wiimote_queue(struct wiimote_data *wdata, const __u8 *buffer,
+								size_t count)
+{
+	unsigned long flags;
+	__u8 newhead;
+
+	if (count > HID_MAX_BUFFER_SIZE) {
+		hid_warn(wdata->hdev, "Sending too large output report\n");
+
+		spin_lock_irqsave(&wdata->queue.lock, flags);
+		goto out_error;
+	}
+
+	/*
+	 * Copy new request into our output queue and check whether the
+	 * queue is full. If it is full, discard this request.
+	 * If it is empty we need to start a new worker that will
+	 * send out the buffer to the hid device.
+	 * If the queue is not empty, then there must be a worker
+	 * that is currently sending out our buffer and this worker
+	 * will reschedule itself until the queue is empty.
+	 */
+
+	spin_lock_irqsave(&wdata->queue.lock, flags);
+
+	memcpy(wdata->queue.outq[wdata->queue.head].data, buffer, count);
+	wdata->queue.outq[wdata->queue.head].size = count;
+	newhead = (wdata->queue.head + 1) % WIIMOTE_BUFSIZE;
+
+	if (wdata->queue.head == wdata->queue.tail) {
+		wdata->queue.head = newhead;
+		schedule_work(&wdata->queue.worker);
+	} else if (newhead != wdata->queue.tail) {
+		wdata->queue.head = newhead;
+	} else {
+		hid_warn(wdata->hdev, "Output queue is full");
+		goto out_error;
+	}
+
+	goto out_unlock;
+
+out_error:
+	wiimote_cmd_abort(wdata);
+out_unlock:
+	spin_unlock_irqrestore(&wdata->queue.lock, flags);
+}
+
+/*
+ * This sets the rumble bit on the given output report if rumble is
+ * currently enabled.
+ * \cmd1 must point to the second byte in the output report => &cmd[1]
+ * This must be called on nearly every output report before passing it
+ * into the output queue!
+ */
+static inline void wiiproto_keep_rumble(struct wiimote_data *wdata, __u8 *cmd1)
+{
+	if (wdata->state.flags & WIIPROTO_FLAG_RUMBLE)
+		*cmd1 |= 0x01;
+}
+
+void wiiproto_req_rumble(struct wiimote_data *wdata, __u8 rumble)
+{
+	__u8 cmd[2];
+
+	rumble = !!rumble;
+	if (rumble == !!(wdata->state.flags & WIIPROTO_FLAG_RUMBLE))
+		return;
+
+	if (rumble)
+		wdata->state.flags |= WIIPROTO_FLAG_RUMBLE;
+	else
+		wdata->state.flags &= ~WIIPROTO_FLAG_RUMBLE;
+
+	cmd[0] = WIIPROTO_REQ_RUMBLE;
+	cmd[1] = 0;
+
+	wiiproto_keep_rumble(wdata, &cmd[1]);
+	wiimote_queue(wdata, cmd, sizeof(cmd));
+}
+
+void wiiproto_req_leds(struct wiimote_data *wdata, int leds)
+{
+	__u8 cmd[2];
+
+	leds &= WIIPROTO_FLAGS_LEDS;
+	if ((wdata->state.flags & WIIPROTO_FLAGS_LEDS) == leds)
+		return;
+	wdata->state.flags = (wdata->state.flags & ~WIIPROTO_FLAGS_LEDS) | leds;
+
+	cmd[0] = WIIPROTO_REQ_LED;
+	cmd[1] = 0;
+
+	if (leds & WIIPROTO_FLAG_LED1)
+		cmd[1] |= 0x10;
+	if (leds & WIIPROTO_FLAG_LED2)
+		cmd[1] |= 0x20;
+	if (leds & WIIPROTO_FLAG_LED3)
+		cmd[1] |= 0x40;
+	if (leds & WIIPROTO_FLAG_LED4)
+		cmd[1] |= 0x80;
+
+	wiiproto_keep_rumble(wdata, &cmd[1]);
+	wiimote_queue(wdata, cmd, sizeof(cmd));
+}
+
+/*
+ * Check what peripherals of the wiimote are currently
+ * active and select a proper DRM that supports all of
+ * the requested data inputs.
+ *
+ * Not all combinations are actually supported. The following
+ * combinations work only with limitations:
+ *  - IR cam in extended or full mode disables any data transmission
+ *    of extension controllers. There is no DRM mode that supports
+ *    extension bytes plus extended/full IR.
+ *  - IR cam with accelerometer and extension *_EXT8 is not supported.
+ *    However, all extensions that need *_EXT8 are devices that don't
+ *    support IR cameras. Hence, this shouldn't happen under normal
+ *    operation.
+ *  - *_EXT16 is only supported in combination with buttons and
+ *    accelerometer. No IR or similar can be active simultaneously. As
+ *    above, all modules that require it are mutually exclusive with
+ *    IR/etc. so this doesn't matter.
+ */
+static __u8 select_drm(struct wiimote_data *wdata)
+{
+	__u8 ir = wdata->state.flags & WIIPROTO_FLAGS_IR;
+	bool ext;
+
+	ext = (wdata->state.flags & WIIPROTO_FLAG_EXT_USED) ||
+	      (wdata->state.flags & WIIPROTO_FLAG_MP_USED);
+
+	/* some 3rd-party balance-boards are hard-coded to KEE, *sigh* */
+	if (wdata->state.devtype == WIIMOTE_DEV_BALANCE_BOARD) {
+		if (ext)
+			return WIIPROTO_REQ_DRM_KEE;
+		else
+			return WIIPROTO_REQ_DRM_K;
+	}
+
+	if (ir == WIIPROTO_FLAG_IR_BASIC) {
+		if (wdata->state.flags & WIIPROTO_FLAG_ACCEL) {
+			/* GEN10 and ealier devices bind IR formats to DRMs.
+			 * Hence, we cannot use DRM_KAI here as it might be
+			 * bound to IR_EXT. Use DRM_KAIE unconditionally so we
+			 * work with all devices and our parsers can use the
+			 * fixed formats, too. */
+			return WIIPROTO_REQ_DRM_KAIE;
+		} else {
+			return WIIPROTO_REQ_DRM_KIE;
+		}
+	} else if (ir == WIIPROTO_FLAG_IR_EXT) {
+		return WIIPROTO_REQ_DRM_KAI;
+	} else if (ir == WIIPROTO_FLAG_IR_FULL) {
+		return WIIPROTO_REQ_DRM_SKAI1;
+	} else {
+		if (wdata->state.flags & WIIPROTO_FLAG_ACCEL) {
+			if (ext)
+				return WIIPROTO_REQ_DRM_KAE;
+			else
+				return WIIPROTO_REQ_DRM_KA;
+		} else {
+			if (ext)
+				return WIIPROTO_REQ_DRM_KEE;
+			else
+				return WIIPROTO_REQ_DRM_K;
+		}
+	}
+}
+
+void wiiproto_req_drm(struct wiimote_data *wdata, __u8 drm)
+{
+	__u8 cmd[3];
+
+	if (wdata->state.flags & WIIPROTO_FLAG_DRM_LOCKED)
+		drm = wdata->state.drm;
+	else if (drm == WIIPROTO_REQ_NULL)
+		drm = select_drm(wdata);
+
+	cmd[0] = WIIPROTO_REQ_DRM;
+	cmd[1] = 0;
+	cmd[2] = drm;
+
+	wdata->state.drm = drm;
+	wiiproto_keep_rumble(wdata, &cmd[1]);
+	wiimote_queue(wdata, cmd, sizeof(cmd));
+}
+
+void wiiproto_req_status(struct wiimote_data *wdata)
+{
+	__u8 cmd[2];
+
+	cmd[0] = WIIPROTO_REQ_SREQ;
+	cmd[1] = 0;
+
+	wiiproto_keep_rumble(wdata, &cmd[1]);
+	wiimote_queue(wdata, cmd, sizeof(cmd));
+}
+
+void wiiproto_req_accel(struct wiimote_data *wdata, __u8 accel)
+{
+	accel = !!accel;
+	if (accel == !!(wdata->state.flags & WIIPROTO_FLAG_ACCEL))
+		return;
+
+	if (accel)
+		wdata->state.flags |= WIIPROTO_FLAG_ACCEL;
+	else
+		wdata->state.flags &= ~WIIPROTO_FLAG_ACCEL;
+
+	wiiproto_req_drm(wdata, WIIPROTO_REQ_NULL);
+}
+
+void wiiproto_req_ir1(struct wiimote_data *wdata, __u8 flags)
+{
+	__u8 cmd[2];
+
+	cmd[0] = WIIPROTO_REQ_IR1;
+	cmd[1] = flags;
+
+	wiiproto_keep_rumble(wdata, &cmd[1]);
+	wiimote_queue(wdata, cmd, sizeof(cmd));
+}
+
+void wiiproto_req_ir2(struct wiimote_data *wdata, __u8 flags)
+{
+	__u8 cmd[2];
+
+	cmd[0] = WIIPROTO_REQ_IR2;
+	cmd[1] = flags;
+
+	wiiproto_keep_rumble(wdata, &cmd[1]);
+	wiimote_queue(wdata, cmd, sizeof(cmd));
+}
+
+#define wiiproto_req_wreg(wdata, os, buf, sz) \
+			wiiproto_req_wmem((wdata), false, (os), (buf), (sz))
+
+#define wiiproto_req_weeprom(wdata, os, buf, sz) \
+			wiiproto_req_wmem((wdata), true, (os), (buf), (sz))
+
+static void wiiproto_req_wmem(struct wiimote_data *wdata, bool eeprom,
+				__u32 offset, const __u8 *buf, __u8 size)
+{
+	__u8 cmd[22];
+
+	if (size > 16 || size == 0) {
+		hid_warn(wdata->hdev, "Invalid length %d wmem request\n", size);
+		return;
+	}
+
+	memset(cmd, 0, sizeof(cmd));
+	cmd[0] = WIIPROTO_REQ_WMEM;
+	cmd[2] = (offset >> 16) & 0xff;
+	cmd[3] = (offset >> 8) & 0xff;
+	cmd[4] = offset & 0xff;
+	cmd[5] = size;
+	memcpy(&cmd[6], buf, size);
+
+	if (!eeprom)
+		cmd[1] |= 0x04;
+
+	wiiproto_keep_rumble(wdata, &cmd[1]);
+	wiimote_queue(wdata, cmd, sizeof(cmd));
+}
+
+void wiiproto_req_rmem(struct wiimote_data *wdata, bool eeprom, __u32 offset,
+								__u16 size)
+{
+	__u8 cmd[7];
+
+	if (size == 0) {
+		hid_warn(wdata->hdev, "Invalid length %d rmem request\n", size);
+		return;
+	}
+
+	cmd[0] = WIIPROTO_REQ_RMEM;
+	cmd[1] = 0;
+	cmd[2] = (offset >> 16) & 0xff;
+	cmd[3] = (offset >> 8) & 0xff;
+	cmd[4] = offset & 0xff;
+	cmd[5] = (size >> 8) & 0xff;
+	cmd[6] = size & 0xff;
+
+	if (!eeprom)
+		cmd[1] |= 0x04;
+
+	wiiproto_keep_rumble(wdata, &cmd[1]);
+	wiimote_queue(wdata, cmd, sizeof(cmd));
+}
+
+/* requries the cmd-mutex to be held */
+int wiimote_cmd_write(struct wiimote_data *wdata, __u32 offset,
+						const __u8 *wmem, __u8 size)
+{
+	unsigned long flags;
+	int ret;
+
+	spin_lock_irqsave(&wdata->state.lock, flags);
+	wiimote_cmd_set(wdata, WIIPROTO_REQ_WMEM, 0);
+	wiiproto_req_wreg(wdata, offset, wmem, size);
+	spin_unlock_irqrestore(&wdata->state.lock, flags);
+
+	ret = wiimote_cmd_wait(wdata);
+	if (!ret && wdata->state.cmd_err)
+		ret = -EIO;
+
+	return ret;
+}
+
+/* requries the cmd-mutex to be held */
+ssize_t wiimote_cmd_read(struct wiimote_data *wdata, __u32 offset, __u8 *rmem,
+								__u8 size)
+{
+	unsigned long flags;
+	ssize_t ret;
+
+	spin_lock_irqsave(&wdata->state.lock, flags);
+	wdata->state.cmd_read_size = size;
+	wdata->state.cmd_read_buf = rmem;
+	wiimote_cmd_set(wdata, WIIPROTO_REQ_RMEM, offset & 0xffff);
+	wiiproto_req_rreg(wdata, offset, size);
+	spin_unlock_irqrestore(&wdata->state.lock, flags);
+
+	ret = wiimote_cmd_wait(wdata);
+
+	spin_lock_irqsave(&wdata->state.lock, flags);
+	wdata->state.cmd_read_buf = NULL;
+	spin_unlock_irqrestore(&wdata->state.lock, flags);
+
+	if (!ret) {
+		if (wdata->state.cmd_read_size == 0)
+			ret = -EIO;
+		else
+			ret = wdata->state.cmd_read_size;
+	}
+
+	return ret;
+}
+
+/* requires the cmd-mutex to be held */
+static int wiimote_cmd_init_ext(struct wiimote_data *wdata)
+{
+	__u8 wmem;
+	int ret;
+
+	/* initialize extension */
+	wmem = 0x55;
+	ret = wiimote_cmd_write(wdata, 0xa400f0, &wmem, sizeof(wmem));
+	if (ret)
+		return ret;
+
+	/* disable default encryption */
+	wmem = 0x0;
+	ret = wiimote_cmd_write(wdata, 0xa400fb, &wmem, sizeof(wmem));
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+/* requires the cmd-mutex to be held */
+static __u8 wiimote_cmd_read_ext(struct wiimote_data *wdata, __u8 *rmem)
+{
+	int ret;
+
+	/* read extension ID */
+	ret = wiimote_cmd_read(wdata, 0xa400fa, rmem, 6);
+	if (ret != 6)
+		return WIIMOTE_EXT_NONE;
+
+	hid_dbg(wdata->hdev, "extension ID: %6phC\n", rmem);
+
+	if (rmem[0] == 0xff && rmem[1] == 0xff && rmem[2] == 0xff &&
+	    rmem[3] == 0xff && rmem[4] == 0xff && rmem[5] == 0xff)
+		return WIIMOTE_EXT_NONE;
+
+	if (rmem[4] == 0x00 && rmem[5] == 0x00)
+		return WIIMOTE_EXT_NUNCHUK;
+	if (rmem[4] == 0x01 && rmem[5] == 0x01)
+		return WIIMOTE_EXT_CLASSIC_CONTROLLER;
+	if (rmem[4] == 0x04 && rmem[5] == 0x02)
+		return WIIMOTE_EXT_BALANCE_BOARD;
+	if (rmem[4] == 0x01 && rmem[5] == 0x20)
+		return WIIMOTE_EXT_PRO_CONTROLLER;
+	if (rmem[0] == 0x01 && rmem[1] == 0x00 &&
+	    rmem[4] == 0x01 && rmem[5] == 0x03)
+		return WIIMOTE_EXT_DRUMS;
+	if (rmem[0] == 0x00 && rmem[1] == 0x00 &&
+	    rmem[4] == 0x01 && rmem[5] == 0x03)
+		return WIIMOTE_EXT_GUITAR;
+
+	return WIIMOTE_EXT_UNKNOWN;
+}
+
+/* requires the cmd-mutex to be held */
+static int wiimote_cmd_init_mp(struct wiimote_data *wdata)
+{
+	__u8 wmem;
+	int ret;
+
+	/* initialize MP */
+	wmem = 0x55;
+	ret = wiimote_cmd_write(wdata, 0xa600f0, &wmem, sizeof(wmem));
+	if (ret)
+		return ret;
+
+	/* disable default encryption */
+	wmem = 0x0;
+	ret = wiimote_cmd_write(wdata, 0xa600fb, &wmem, sizeof(wmem));
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+/* requires the cmd-mutex to be held */
+static bool wiimote_cmd_map_mp(struct wiimote_data *wdata, __u8 exttype)
+{
+	__u8 wmem;
+
+	/* map MP with correct pass-through mode */
+	switch (exttype) {
+	case WIIMOTE_EXT_CLASSIC_CONTROLLER:
+	case WIIMOTE_EXT_DRUMS:
+	case WIIMOTE_EXT_GUITAR:
+		wmem = 0x07;
+		break;
+	case WIIMOTE_EXT_NUNCHUK:
+		wmem = 0x05;
+		break;
+	default:
+		wmem = 0x04;
+		break;
+	}
+
+	return wiimote_cmd_write(wdata, 0xa600fe, &wmem, sizeof(wmem));
+}
+
+/* requires the cmd-mutex to be held */
+static bool wiimote_cmd_read_mp(struct wiimote_data *wdata, __u8 *rmem)
+{
+	int ret;
+
+	/* read motion plus ID */
+	ret = wiimote_cmd_read(wdata, 0xa600fa, rmem, 6);
+	if (ret != 6)
+		return false;
+
+	hid_dbg(wdata->hdev, "motion plus ID: %6phC\n", rmem);
+
+	if (rmem[5] == 0x05)
+		return true;
+
+	hid_info(wdata->hdev, "unknown motion plus ID: %6phC\n", rmem);
+
+	return false;
+}
+
+/* requires the cmd-mutex to be held */
+static __u8 wiimote_cmd_read_mp_mapped(struct wiimote_data *wdata)
+{
+	int ret;
+	__u8 rmem[6];
+
+	/* read motion plus ID */
+	ret = wiimote_cmd_read(wdata, 0xa400fa, rmem, 6);
+	if (ret != 6)
+		return WIIMOTE_MP_NONE;
+
+	hid_dbg(wdata->hdev, "mapped motion plus ID: %6phC\n", rmem);
+
+	if (rmem[0] == 0xff && rmem[1] == 0xff && rmem[2] == 0xff &&
+	    rmem[3] == 0xff && rmem[4] == 0xff && rmem[5] == 0xff)
+		return WIIMOTE_MP_NONE;
+
+	if (rmem[4] == 0x04 && rmem[5] == 0x05)
+		return WIIMOTE_MP_SINGLE;
+	else if (rmem[4] == 0x05 && rmem[5] == 0x05)
+		return WIIMOTE_MP_PASSTHROUGH_NUNCHUK;
+	else if (rmem[4] == 0x07 && rmem[5] == 0x05)
+		return WIIMOTE_MP_PASSTHROUGH_CLASSIC;
+
+	return WIIMOTE_MP_UNKNOWN;
+}
+
+/* device module handling */
+
+static const __u8 * const wiimote_devtype_mods[WIIMOTE_DEV_NUM] = {
+	[WIIMOTE_DEV_PENDING] = (const __u8[]){
+		WIIMOD_NULL,
+	},
+	[WIIMOTE_DEV_UNKNOWN] = (const __u8[]){
+		WIIMOD_NO_MP,
+		WIIMOD_NULL,
+	},
+	[WIIMOTE_DEV_GENERIC] = (const __u8[]){
+		WIIMOD_KEYS,
+		WIIMOD_RUMBLE,
+		WIIMOD_BATTERY,
+		WIIMOD_LED1,
+		WIIMOD_LED2,
+		WIIMOD_LED3,
+		WIIMOD_LED4,
+		WIIMOD_ACCEL,
+		WIIMOD_IR,
+		WIIMOD_NULL,
+	},
+	[WIIMOTE_DEV_GEN10] = (const __u8[]){
+		WIIMOD_KEYS,
+		WIIMOD_RUMBLE,
+		WIIMOD_BATTERY,
+		WIIMOD_LED1,
+		WIIMOD_LED2,
+		WIIMOD_LED3,
+		WIIMOD_LED4,
+		WIIMOD_ACCEL,
+		WIIMOD_IR,
+		WIIMOD_NULL,
+	},
+	[WIIMOTE_DEV_GEN20] = (const __u8[]){
+		WIIMOD_KEYS,
+		WIIMOD_RUMBLE,
+		WIIMOD_BATTERY,
+		WIIMOD_LED1,
+		WIIMOD_LED2,
+		WIIMOD_LED3,
+		WIIMOD_LED4,
+		WIIMOD_ACCEL,
+		WIIMOD_IR,
+		WIIMOD_BUILTIN_MP,
+		WIIMOD_NULL,
+	},
+	[WIIMOTE_DEV_BALANCE_BOARD] = (const __u8[]) {
+		WIIMOD_BATTERY,
+		WIIMOD_LED1,
+		WIIMOD_NO_MP,
+		WIIMOD_NULL,
+	},
+	[WIIMOTE_DEV_PRO_CONTROLLER] = (const __u8[]) {
+		WIIMOD_BATTERY,
+		WIIMOD_LED1,
+		WIIMOD_LED2,
+		WIIMOD_LED3,
+		WIIMOD_LED4,
+		WIIMOD_NO_MP,
+		WIIMOD_NULL,
+	},
+};
+
+static void wiimote_modules_load(struct wiimote_data *wdata,
+				 unsigned int devtype)
+{
+	bool need_input = false;
+	const __u8 *mods, *iter;
+	const struct wiimod_ops *ops;
+	int ret;
+
+	mods = wiimote_devtype_mods[devtype];
+
+	for (iter = mods; *iter != WIIMOD_NULL; ++iter) {
+		if (wiimod_table[*iter]->flags & WIIMOD_FLAG_INPUT) {
+			need_input = true;
+			break;
+		}
+	}
+
+	if (need_input) {
+		wdata->input = input_allocate_device();
+		if (!wdata->input)
+			return;
+
+		input_set_drvdata(wdata->input, wdata);
+		wdata->input->dev.parent = &wdata->hdev->dev;
+		wdata->input->id.bustype = wdata->hdev->bus;
+		wdata->input->id.vendor = wdata->hdev->vendor;
+		wdata->input->id.product = wdata->hdev->product;
+		wdata->input->id.version = wdata->hdev->version;
+		wdata->input->name = WIIMOTE_NAME;
+	}
+
+	for (iter = mods; *iter != WIIMOD_NULL; ++iter) {
+		ops = wiimod_table[*iter];
+		if (!ops->probe)
+			continue;
+
+		ret = ops->probe(ops, wdata);
+		if (ret)
+			goto error;
+	}
+
+	if (wdata->input) {
+		ret = input_register_device(wdata->input);
+		if (ret)
+			goto error;
+	}
+
+	spin_lock_irq(&wdata->state.lock);
+	wdata->state.devtype = devtype;
+	spin_unlock_irq(&wdata->state.lock);
+	return;
+
+error:
+	for ( ; iter-- != mods; ) {
+		ops = wiimod_table[*iter];
+		if (ops->remove)
+			ops->remove(ops, wdata);
+	}
+
+	if (wdata->input) {
+		input_free_device(wdata->input);
+		wdata->input = NULL;
+	}
+}
+
+static void wiimote_modules_unload(struct wiimote_data *wdata)
+{
+	const __u8 *mods, *iter;
+	const struct wiimod_ops *ops;
+	unsigned long flags;
+
+	mods = wiimote_devtype_mods[wdata->state.devtype];
+
+	spin_lock_irqsave(&wdata->state.lock, flags);
+	wdata->state.devtype = WIIMOTE_DEV_UNKNOWN;
+	spin_unlock_irqrestore(&wdata->state.lock, flags);
+
+	/* find end of list */
+	for (iter = mods; *iter != WIIMOD_NULL; ++iter)
+		/* empty */ ;
+
+	if (wdata->input) {
+		input_get_device(wdata->input);
+		input_unregister_device(wdata->input);
+	}
+
+	for ( ; iter-- != mods; ) {
+		ops = wiimod_table[*iter];
+		if (ops->remove)
+			ops->remove(ops, wdata);
+	}
+
+	if (wdata->input) {
+		input_put_device(wdata->input);
+		wdata->input = NULL;
+	}
+}
+
+/* device extension handling */
+
+static void wiimote_ext_load(struct wiimote_data *wdata, unsigned int ext)
+{
+	unsigned long flags;
+	const struct wiimod_ops *ops;
+	int ret;
+
+	ops = wiimod_ext_table[ext];
+
+	if (ops->probe) {
+		ret = ops->probe(ops, wdata);
+		if (ret)
+			ext = WIIMOTE_EXT_UNKNOWN;
+	}
+
+	spin_lock_irqsave(&wdata->state.lock, flags);
+	wdata->state.exttype = ext;
+	spin_unlock_irqrestore(&wdata->state.lock, flags);
+}
+
+static void wiimote_ext_unload(struct wiimote_data *wdata)
+{
+	unsigned long flags;
+	const struct wiimod_ops *ops;
+
+	ops = wiimod_ext_table[wdata->state.exttype];
+
+	spin_lock_irqsave(&wdata->state.lock, flags);
+	wdata->state.exttype = WIIMOTE_EXT_UNKNOWN;
+	wdata->state.flags &= ~WIIPROTO_FLAG_EXT_USED;
+	spin_unlock_irqrestore(&wdata->state.lock, flags);
+
+	if (ops->remove)
+		ops->remove(ops, wdata);
+}
+
+static void wiimote_mp_load(struct wiimote_data *wdata)
+{
+	unsigned long flags;
+	const struct wiimod_ops *ops;
+	int ret;
+	__u8 mode = 2;
+
+	ops = &wiimod_mp;
+	if (ops->probe) {
+		ret = ops->probe(ops, wdata);
+		if (ret)
+			mode = 1;
+	}
+
+	spin_lock_irqsave(&wdata->state.lock, flags);
+	wdata->state.mp = mode;
+	spin_unlock_irqrestore(&wdata->state.lock, flags);
+}
+
+static void wiimote_mp_unload(struct wiimote_data *wdata)
+{
+	unsigned long flags;
+	const struct wiimod_ops *ops;
+
+	if (wdata->state.mp < 2)
+		return;
+
+	ops = &wiimod_mp;
+
+	spin_lock_irqsave(&wdata->state.lock, flags);
+	wdata->state.mp = 0;
+	wdata->state.flags &= ~WIIPROTO_FLAG_MP_USED;
+	spin_unlock_irqrestore(&wdata->state.lock, flags);
+
+	if (ops->remove)
+		ops->remove(ops, wdata);
+}
+
+/* device (re-)initialization and detection */
+
+static const char *wiimote_devtype_names[WIIMOTE_DEV_NUM] = {
+	[WIIMOTE_DEV_PENDING] = "Pending",
+	[WIIMOTE_DEV_UNKNOWN] = "Unknown",
+	[WIIMOTE_DEV_GENERIC] = "Generic",
+	[WIIMOTE_DEV_GEN10] = "Nintendo Wii Remote (Gen 1)",
+	[WIIMOTE_DEV_GEN20] = "Nintendo Wii Remote Plus (Gen 2)",
+	[WIIMOTE_DEV_BALANCE_BOARD] = "Nintendo Wii Balance Board",
+	[WIIMOTE_DEV_PRO_CONTROLLER] = "Nintendo Wii U Pro Controller",
+};
+
+/* Try to guess the device type based on all collected information. We
+ * first try to detect by static extension types, then VID/PID and the
+ * device name. If we cannot detect the device, we use
+ * WIIMOTE_DEV_GENERIC so all modules will get probed on the device. */
+static void wiimote_init_set_type(struct wiimote_data *wdata,
+				  __u8 exttype)
+{
+	__u8 devtype = WIIMOTE_DEV_GENERIC;
+	__u16 vendor, product;
+	const char *name;
+
+	vendor = wdata->hdev->vendor;
+	product = wdata->hdev->product;
+	name = wdata->hdev->name;
+
+	if (exttype == WIIMOTE_EXT_BALANCE_BOARD) {
+		devtype = WIIMOTE_DEV_BALANCE_BOARD;
+		goto done;
+	} else if (exttype == WIIMOTE_EXT_PRO_CONTROLLER) {
+		devtype = WIIMOTE_DEV_PRO_CONTROLLER;
+		goto done;
+	}
+
+	if (!strcmp(name, "Nintendo RVL-CNT-01")) {
+		devtype = WIIMOTE_DEV_GEN10;
+		goto done;
+	} else if (!strcmp(name, "Nintendo RVL-CNT-01-TR")) {
+		devtype = WIIMOTE_DEV_GEN20;
+		goto done;
+	} else if (!strcmp(name, "Nintendo RVL-WBC-01")) {
+		devtype = WIIMOTE_DEV_BALANCE_BOARD;
+		goto done;
+	} else if (!strcmp(name, "Nintendo RVL-CNT-01-UC")) {
+		devtype = WIIMOTE_DEV_PRO_CONTROLLER;
+		goto done;
+	}
+
+	if (vendor == USB_VENDOR_ID_NINTENDO) {
+		if (product == USB_DEVICE_ID_NINTENDO_WIIMOTE) {
+			devtype = WIIMOTE_DEV_GEN10;
+			goto done;
+		} else if (product == USB_DEVICE_ID_NINTENDO_WIIMOTE2) {
+			devtype = WIIMOTE_DEV_GEN20;
+			goto done;
+		}
+	}
+
+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);
+	else
+		hid_info(wdata->hdev, "detected device: %s\n",
+			 wiimote_devtype_names[devtype]);
+
+	wiimote_modules_load(wdata, devtype);
+}
+
+static void wiimote_init_detect(struct wiimote_data *wdata)
+{
+	__u8 exttype = WIIMOTE_EXT_NONE, extdata[6];
+	bool ext;
+	int ret;
+
+	wiimote_cmd_acquire_noint(wdata);
+
+	spin_lock_irq(&wdata->state.lock);
+	wdata->state.devtype = WIIMOTE_DEV_UNKNOWN;
+	wiimote_cmd_set(wdata, WIIPROTO_REQ_SREQ, 0);
+	wiiproto_req_status(wdata);
+	spin_unlock_irq(&wdata->state.lock);
+
+	ret = wiimote_cmd_wait_noint(wdata);
+	if (ret)
+		goto out_release;
+
+	spin_lock_irq(&wdata->state.lock);
+	ext = wdata->state.flags & WIIPROTO_FLAG_EXT_PLUGGED;
+	spin_unlock_irq(&wdata->state.lock);
+
+	if (!ext)
+		goto out_release;
+
+	wiimote_cmd_init_ext(wdata);
+	exttype = wiimote_cmd_read_ext(wdata, extdata);
+
+out_release:
+	wiimote_cmd_release(wdata);
+	wiimote_init_set_type(wdata, exttype);
+
+	/* schedule MP timer */
+	spin_lock_irq(&wdata->state.lock);
+	if (!(wdata->state.flags & WIIPROTO_FLAG_BUILTIN_MP) &&
+	    !(wdata->state.flags & WIIPROTO_FLAG_NO_MP))
+		mod_timer(&wdata->timer, jiffies + HZ * 4);
+	spin_unlock_irq(&wdata->state.lock);
+}
+
+/*
+ * MP hotplug events are not generated by the wiimote. Therefore, we need
+ * polling to detect it. We use a 4s interval for polling MP registers. This
+ * seems reasonable considering applications can trigger it manually via
+ * sysfs requests.
+ */
+static void wiimote_init_poll_mp(struct wiimote_data *wdata)
+{
+	bool mp;
+	__u8 mpdata[6];
+
+	wiimote_cmd_acquire_noint(wdata);
+	wiimote_cmd_init_mp(wdata);
+	mp = wiimote_cmd_read_mp(wdata, mpdata);
+	wiimote_cmd_release(wdata);
+
+	/* load/unload MP module if it changed */
+	if (mp) {
+		if (!wdata->state.mp) {
+			hid_info(wdata->hdev, "detected extension: Nintendo Wii Motion Plus\n");
+			wiimote_mp_load(wdata);
+		}
+	} else if (wdata->state.mp) {
+		wiimote_mp_unload(wdata);
+	}
+
+	mod_timer(&wdata->timer, jiffies + HZ * 4);
+}
+
+/*
+ * Check whether the wiimote is in the expected state. The extension registers
+ * may change during hotplug and initialization so we might get hotplug events
+ * that we caused by remapping some memory.
+ * We use some heuristics here to check known states. If the wiimote is in the
+ * expected state, we can ignore the hotplug event.
+ *
+ * Returns "true" if the device is in expected state, "false" if we should
+ * redo hotplug handling and extension initialization.
+ */
+static bool wiimote_init_check(struct wiimote_data *wdata)
+{
+	__u32 flags;
+	__u8 type, data[6];
+	bool ret, poll_mp;
+
+	spin_lock_irq(&wdata->state.lock);
+	flags = wdata->state.flags;
+	spin_unlock_irq(&wdata->state.lock);
+
+	wiimote_cmd_acquire_noint(wdata);
+
+	/* If MP is used and active, but the extension is not, we expect:
+	 *   read_mp_mapped() == WIIMOTE_MP_SINGLE
+	 *   state.flags == !EXT_ACTIVE && !MP_PLUGGED && MP_ACTIVE
+	 * We do not check EXT_PLUGGED because it might change during
+	 * initialization of MP without extensions.
+	 *  - If MP is unplugged/replugged, read_mp_mapped() fails
+	 *  - If EXT is plugged, MP_PLUGGED will get set */
+	if (wdata->state.exttype == WIIMOTE_EXT_NONE &&
+	    wdata->state.mp > 0 && (flags & WIIPROTO_FLAG_MP_USED)) {
+		type = wiimote_cmd_read_mp_mapped(wdata);
+		ret = type == WIIMOTE_MP_SINGLE;
+
+		spin_lock_irq(&wdata->state.lock);
+		ret = ret && !(wdata->state.flags & WIIPROTO_FLAG_EXT_ACTIVE);
+		ret = ret && !(wdata->state.flags & WIIPROTO_FLAG_MP_PLUGGED);
+		ret = ret && (wdata->state.flags & WIIPROTO_FLAG_MP_ACTIVE);
+		spin_unlock_irq(&wdata->state.lock);
+
+		if (!ret)
+			hid_dbg(wdata->hdev, "state left: !EXT && MP\n");
+
+		/* while MP is mapped, we get EXT_PLUGGED events */
+		poll_mp = false;
+
+		goto out_release;
+	}
+
+	/* If MP is unused, but the extension port is used, we expect:
+	 *   read_ext == state.exttype
+	 *   state.flags == !MP_ACTIVE && EXT_ACTIVE
+	 * - If MP is plugged/unplugged, our timer detects it
+	 * - If EXT is unplugged/replugged, EXT_ACTIVE will become unset */
+	if (!(flags & WIIPROTO_FLAG_MP_USED) &&
+	    wdata->state.exttype != WIIMOTE_EXT_NONE) {
+		type = wiimote_cmd_read_ext(wdata, data);
+		ret = type == wdata->state.exttype;
+
+		spin_lock_irq(&wdata->state.lock);
+		ret = ret && !(wdata->state.flags & WIIPROTO_FLAG_MP_ACTIVE);
+		ret = ret && (wdata->state.flags & WIIPROTO_FLAG_EXT_ACTIVE);
+		spin_unlock_irq(&wdata->state.lock);
+
+		if (!ret)
+			hid_dbg(wdata->hdev, "state left: EXT && !MP\n");
+
+		/* poll MP for hotplug events */
+		poll_mp = true;
+
+		goto out_release;
+	}
+
+	/* If neither MP nor an extension are used, we expect:
+	 *   read_ext() == WIIMOTE_EXT_NONE
+	 *   state.flags == !MP_ACTIVE && !EXT_ACTIVE && !EXT_PLUGGED
+	 * No need to perform any action in this case as everything is
+	 * disabled already.
+	 * - If MP is plugged/unplugged, our timer detects it
+	 * - If EXT is plugged, EXT_PLUGGED will be set */
+	if (!(flags & WIIPROTO_FLAG_MP_USED) &&
+	    wdata->state.exttype == WIIMOTE_EXT_NONE) {
+		type = wiimote_cmd_read_ext(wdata, data);
+		ret = type == wdata->state.exttype;
+
+		spin_lock_irq(&wdata->state.lock);
+		ret = ret && !(wdata->state.flags & WIIPROTO_FLAG_EXT_ACTIVE);
+		ret = ret && !(wdata->state.flags & WIIPROTO_FLAG_MP_ACTIVE);
+		ret = ret && !(wdata->state.flags & WIIPROTO_FLAG_EXT_PLUGGED);
+		spin_unlock_irq(&wdata->state.lock);
+
+		if (!ret)
+			hid_dbg(wdata->hdev, "state left: !EXT && !MP\n");
+
+		/* poll MP for hotplug events */
+		poll_mp = true;
+
+		goto out_release;
+	}
+
+	/* The trickiest part is if both EXT and MP are active. We cannot read
+	 * the EXT ID, anymore, because MP is mapped over it. However, we use
+	 * a handy trick here:
+	 *   - EXT_ACTIVE is unset whenever !MP_PLUGGED is sent
+	 * MP_PLUGGED might be re-sent again before we are scheduled, but
+	 * EXT_ACTIVE will stay unset.
+	 * So it is enough to check for mp_mapped() and MP_ACTIVE and
+	 * EXT_ACTIVE. EXT_PLUGGED is a sanity check. */
+	if (wdata->state.exttype != WIIMOTE_EXT_NONE &&
+	    wdata->state.mp > 0 && (flags & WIIPROTO_FLAG_MP_USED)) {
+		type = wiimote_cmd_read_mp_mapped(wdata);
+		ret = type != WIIMOTE_MP_NONE;
+		ret = ret && type != WIIMOTE_MP_UNKNOWN;
+		ret = ret && type != WIIMOTE_MP_SINGLE;
+
+		spin_lock_irq(&wdata->state.lock);
+		ret = ret && (wdata->state.flags & WIIPROTO_FLAG_EXT_PLUGGED);
+		ret = ret && (wdata->state.flags & WIIPROTO_FLAG_EXT_ACTIVE);
+		ret = ret && (wdata->state.flags & WIIPROTO_FLAG_MP_ACTIVE);
+		spin_unlock_irq(&wdata->state.lock);
+
+		if (!ret)
+			hid_dbg(wdata->hdev, "state left: EXT && MP\n");
+
+		/* while MP is mapped, we get EXT_PLUGGED events */
+		poll_mp = false;
+
+		goto out_release;
+	}
+
+	/* unknown state */
+	ret = false;
+
+out_release:
+	wiimote_cmd_release(wdata);
+
+	/* only poll for MP if requested and if state didn't change */
+	if (ret && poll_mp && !(flags & WIIPROTO_FLAG_BUILTIN_MP) &&
+	    !(flags & WIIPROTO_FLAG_NO_MP))
+		wiimote_init_poll_mp(wdata);
+
+	return ret;
+}
+
+static const char *wiimote_exttype_names[WIIMOTE_EXT_NUM] = {
+	[WIIMOTE_EXT_NONE] = "None",
+	[WIIMOTE_EXT_UNKNOWN] = "Unknown",
+	[WIIMOTE_EXT_NUNCHUK] = "Nintendo Wii Nunchuk",
+	[WIIMOTE_EXT_CLASSIC_CONTROLLER] = "Nintendo Wii Classic Controller",
+	[WIIMOTE_EXT_BALANCE_BOARD] = "Nintendo Wii Balance Board",
+	[WIIMOTE_EXT_PRO_CONTROLLER] = "Nintendo Wii U Pro Controller",
+	[WIIMOTE_EXT_DRUMS] = "Nintendo Wii Drums",
+	[WIIMOTE_EXT_GUITAR] = "Nintendo Wii Guitar",
+};
+
+/*
+ * Handle hotplug events
+ * If we receive an hotplug event and the device-check failed, we deinitialize
+ * the extension ports, re-read all extension IDs and set the device into
+ * the desired state. This involves mapping MP into the main extension
+ * registers, setting up extension passthrough modes and initializing the
+ * requested extensions.
+ */
+static void wiimote_init_hotplug(struct wiimote_data *wdata)
+{
+	__u8 exttype, extdata[6], mpdata[6];
+	__u32 flags;
+	bool mp;
+
+	hid_dbg(wdata->hdev, "detect extensions..\n");
+
+	wiimote_cmd_acquire_noint(wdata);
+
+	spin_lock_irq(&wdata->state.lock);
+
+	/* get state snapshot that we will then work on */
+	flags = wdata->state.flags;
+
+	/* disable event forwarding temporarily */
+	wdata->state.flags &= ~WIIPROTO_FLAG_EXT_ACTIVE;
+	wdata->state.flags &= ~WIIPROTO_FLAG_MP_ACTIVE;
+
+	spin_unlock_irq(&wdata->state.lock);
+
+	/* init extension and MP (deactivates current extension or MP) */
+	wiimote_cmd_init_ext(wdata);
+	if (flags & WIIPROTO_FLAG_NO_MP) {
+		mp = false;
+	} else {
+		wiimote_cmd_init_mp(wdata);
+		mp = wiimote_cmd_read_mp(wdata, mpdata);
+	}
+	exttype = wiimote_cmd_read_ext(wdata, extdata);
+
+	wiimote_cmd_release(wdata);
+
+	/* load/unload extension module if it changed */
+	if (exttype != wdata->state.exttype) {
+		/* unload previous extension */
+		wiimote_ext_unload(wdata);
+
+		if (exttype == WIIMOTE_EXT_UNKNOWN) {
+			hid_info(wdata->hdev, "cannot detect extension; %6phC\n",
+				 extdata);
+		} else if (exttype == WIIMOTE_EXT_NONE) {
+			spin_lock_irq(&wdata->state.lock);
+			wdata->state.exttype = WIIMOTE_EXT_NONE;
+			spin_unlock_irq(&wdata->state.lock);
+		} else {
+			hid_info(wdata->hdev, "detected extension: %s\n",
+				 wiimote_exttype_names[exttype]);
+			/* try loading new extension */
+			wiimote_ext_load(wdata, exttype);
+		}
+	}
+
+	/* load/unload MP module if it changed */
+	if (mp) {
+		if (!wdata->state.mp) {
+			hid_info(wdata->hdev, "detected extension: Nintendo Wii Motion Plus\n");
+			wiimote_mp_load(wdata);
+		}
+	} else if (wdata->state.mp) {
+		wiimote_mp_unload(wdata);
+	}
+
+	/* if MP is not used, do not map or activate it */
+	if (!(flags & WIIPROTO_FLAG_MP_USED))
+		mp = false;
+
+	/* map MP into main extension registers if used */
+	if (mp) {
+		wiimote_cmd_acquire_noint(wdata);
+		wiimote_cmd_map_mp(wdata, exttype);
+		wiimote_cmd_release(wdata);
+
+		/* delete MP hotplug timer */
+		del_timer_sync(&wdata->timer);
+	} else {
+		/* reschedule MP hotplug timer */
+		if (!(flags & WIIPROTO_FLAG_BUILTIN_MP) &&
+		    !(flags & WIIPROTO_FLAG_NO_MP))
+			mod_timer(&wdata->timer, jiffies + HZ * 4);
+	}
+
+	spin_lock_irq(&wdata->state.lock);
+
+	/* enable data forwarding again and set expected hotplug state */
+	if (mp) {
+		wdata->state.flags |= WIIPROTO_FLAG_MP_ACTIVE;
+		if (wdata->state.exttype == WIIMOTE_EXT_NONE) {
+			wdata->state.flags &= ~WIIPROTO_FLAG_EXT_PLUGGED;
+			wdata->state.flags &= ~WIIPROTO_FLAG_MP_PLUGGED;
+		} else {
+			wdata->state.flags &= ~WIIPROTO_FLAG_EXT_PLUGGED;
+			wdata->state.flags |= WIIPROTO_FLAG_MP_PLUGGED;
+			wdata->state.flags |= WIIPROTO_FLAG_EXT_ACTIVE;
+		}
+	} else if (wdata->state.exttype != WIIMOTE_EXT_NONE) {
+		wdata->state.flags |= WIIPROTO_FLAG_EXT_ACTIVE;
+	}
+
+	/* request status report for hotplug state updates */
+	wiiproto_req_status(wdata);
+
+	spin_unlock_irq(&wdata->state.lock);
+
+	hid_dbg(wdata->hdev, "detected extensions: MP: %d EXT: %d\n",
+		wdata->state.mp, wdata->state.exttype);
+}
+
+static void wiimote_init_worker(struct work_struct *work)
+{
+	struct wiimote_data *wdata = container_of(work, struct wiimote_data,
+						  init_worker);
+	bool changed = false;
+
+	if (wdata->state.devtype == WIIMOTE_DEV_PENDING) {
+		wiimote_init_detect(wdata);
+		changed = true;
+	}
+
+	if (changed || !wiimote_init_check(wdata))
+		wiimote_init_hotplug(wdata);
+
+	if (changed)
+		kobject_uevent(&wdata->hdev->dev.kobj, KOBJ_CHANGE);
+}
+
+void __wiimote_schedule(struct wiimote_data *wdata)
+{
+	if (!(wdata->state.flags & WIIPROTO_FLAG_EXITING))
+		schedule_work(&wdata->init_worker);
+}
+
+static void wiimote_schedule(struct wiimote_data *wdata)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&wdata->state.lock, flags);
+	__wiimote_schedule(wdata);
+	spin_unlock_irqrestore(&wdata->state.lock, flags);
+}
+
+static void wiimote_init_timeout(struct timer_list *t)
+{
+	struct wiimote_data *wdata = from_timer(wdata, t, timer);
+
+	wiimote_schedule(wdata);
+}
+
+/* protocol handlers */
+
+static void handler_keys(struct wiimote_data *wdata, const __u8 *payload)
+{
+	const __u8 *iter, *mods;
+	const struct wiimod_ops *ops;
+
+	ops = wiimod_ext_table[wdata->state.exttype];
+	if (ops->in_keys) {
+		ops->in_keys(wdata, payload);
+		return;
+	}
+
+	mods = wiimote_devtype_mods[wdata->state.devtype];
+	for (iter = mods; *iter != WIIMOD_NULL; ++iter) {
+		ops = wiimod_table[*iter];
+		if (ops->in_keys) {
+			ops->in_keys(wdata, payload);
+			break;
+		}
+	}
+}
+
+static void handler_accel(struct wiimote_data *wdata, const __u8 *payload)
+{
+	const __u8 *iter, *mods;
+	const struct wiimod_ops *ops;
+
+	ops = wiimod_ext_table[wdata->state.exttype];
+	if (ops->in_accel) {
+		ops->in_accel(wdata, payload);
+		return;
+	}
+
+	mods = wiimote_devtype_mods[wdata->state.devtype];
+	for (iter = mods; *iter != WIIMOD_NULL; ++iter) {
+		ops = wiimod_table[*iter];
+		if (ops->in_accel) {
+			ops->in_accel(wdata, payload);
+			break;
+		}
+	}
+}
+
+static bool valid_ext_handler(const struct wiimod_ops *ops, size_t len)
+{
+	if (!ops->in_ext)
+		return false;
+	if ((ops->flags & WIIMOD_FLAG_EXT8) && len < 8)
+		return false;
+	if ((ops->flags & WIIMOD_FLAG_EXT16) && len < 16)
+		return false;
+
+	return true;
+}
+
+static void handler_ext(struct wiimote_data *wdata, const __u8 *payload,
+			size_t len)
+{
+	static const __u8 invalid[21] = { 0xff, 0xff, 0xff, 0xff,
+					  0xff, 0xff, 0xff, 0xff,
+					  0xff, 0xff, 0xff, 0xff,
+					  0xff, 0xff, 0xff, 0xff,
+					  0xff, 0xff, 0xff, 0xff,
+					  0xff };
+	const __u8 *iter, *mods;
+	const struct wiimod_ops *ops;
+	bool is_mp;
+
+	if (len > 21)
+		len = 21;
+	if (len < 6 || !memcmp(payload, invalid, len))
+		return;
+
+	/* if MP is active, track MP slot hotplugging */
+	if (wdata->state.flags & WIIPROTO_FLAG_MP_ACTIVE) {
+		/* this bit is set for invalid events (eg. during hotplug) */
+		if (payload[5] & 0x01)
+			return;
+
+		if (payload[4] & 0x01) {
+			if (!(wdata->state.flags & WIIPROTO_FLAG_MP_PLUGGED)) {
+				hid_dbg(wdata->hdev, "MP hotplug: 1\n");
+				wdata->state.flags |= WIIPROTO_FLAG_MP_PLUGGED;
+				__wiimote_schedule(wdata);
+			}
+		} else {
+			if (wdata->state.flags & WIIPROTO_FLAG_MP_PLUGGED) {
+				hid_dbg(wdata->hdev, "MP hotplug: 0\n");
+				wdata->state.flags &= ~WIIPROTO_FLAG_MP_PLUGGED;
+				wdata->state.flags &= ~WIIPROTO_FLAG_EXT_ACTIVE;
+				__wiimote_schedule(wdata);
+			}
+		}
+
+		/* detect MP data that is sent interleaved with EXT data */
+		is_mp = payload[5] & 0x02;
+	} else {
+		is_mp = false;
+	}
+
+	/* ignore EXT events if no extension is active */
+	if (!(wdata->state.flags & WIIPROTO_FLAG_EXT_ACTIVE) && !is_mp)
+		return;
+
+	/* try forwarding to extension handler, first */
+	ops = wiimod_ext_table[wdata->state.exttype];
+	if (is_mp && ops->in_mp) {
+		ops->in_mp(wdata, payload);
+		return;
+	} else if (!is_mp && valid_ext_handler(ops, len)) {
+		ops->in_ext(wdata, payload);
+		return;
+	}
+
+	/* try forwarding to MP handler */
+	ops = &wiimod_mp;
+	if (is_mp && ops->in_mp) {
+		ops->in_mp(wdata, payload);
+		return;
+	} else if (!is_mp && valid_ext_handler(ops, len)) {
+		ops->in_ext(wdata, payload);
+		return;
+	}
+
+	/* try forwarding to loaded modules */
+	mods = wiimote_devtype_mods[wdata->state.devtype];
+	for (iter = mods; *iter != WIIMOD_NULL; ++iter) {
+		ops = wiimod_table[*iter];
+		if (is_mp && ops->in_mp) {
+			ops->in_mp(wdata, payload);
+			return;
+		} else if (!is_mp && valid_ext_handler(ops, len)) {
+			ops->in_ext(wdata, payload);
+			return;
+		}
+	}
+}
+
+#define ir_to_input0(wdata, ir, packed) handler_ir((wdata), (ir), (packed), 0)
+#define ir_to_input1(wdata, ir, packed) handler_ir((wdata), (ir), (packed), 1)
+#define ir_to_input2(wdata, ir, packed) handler_ir((wdata), (ir), (packed), 2)
+#define ir_to_input3(wdata, ir, packed) handler_ir((wdata), (ir), (packed), 3)
+
+static void handler_ir(struct wiimote_data *wdata, const __u8 *payload,
+		       bool packed, unsigned int id)
+{
+	const __u8 *iter, *mods;
+	const struct wiimod_ops *ops;
+
+	ops = wiimod_ext_table[wdata->state.exttype];
+	if (ops->in_ir) {
+		ops->in_ir(wdata, payload, packed, id);
+		return;
+	}
+
+	mods = wiimote_devtype_mods[wdata->state.devtype];
+	for (iter = mods; *iter != WIIMOD_NULL; ++iter) {
+		ops = wiimod_table[*iter];
+		if (ops->in_ir) {
+			ops->in_ir(wdata, payload, packed, id);
+			break;
+		}
+	}
+}
+
+/* reduced status report with "BB BB" key data only */
+static void handler_status_K(struct wiimote_data *wdata,
+			     const __u8 *payload)
+{
+	handler_keys(wdata, payload);
+
+	/* on status reports the drm is reset so we need to resend the drm */
+	wiiproto_req_drm(wdata, WIIPROTO_REQ_NULL);
+}
+
+/* extended status report with "BB BB LF 00 00 VV" data */
+static void handler_status(struct wiimote_data *wdata, const __u8 *payload)
+{
+	handler_status_K(wdata, payload);
+
+	/* update extension status */
+	if (payload[2] & 0x02) {
+		if (!(wdata->state.flags & WIIPROTO_FLAG_EXT_PLUGGED)) {
+			hid_dbg(wdata->hdev, "EXT hotplug: 1\n");
+			wdata->state.flags |= WIIPROTO_FLAG_EXT_PLUGGED;
+			__wiimote_schedule(wdata);
+		}
+	} else {
+		if (wdata->state.flags & WIIPROTO_FLAG_EXT_PLUGGED) {
+			hid_dbg(wdata->hdev, "EXT hotplug: 0\n");
+			wdata->state.flags &= ~WIIPROTO_FLAG_EXT_PLUGGED;
+			wdata->state.flags &= ~WIIPROTO_FLAG_MP_PLUGGED;
+			wdata->state.flags &= ~WIIPROTO_FLAG_EXT_ACTIVE;
+			wdata->state.flags &= ~WIIPROTO_FLAG_MP_ACTIVE;
+			__wiimote_schedule(wdata);
+		}
+	}
+
+	wdata->state.cmd_battery = payload[5];
+	if (wiimote_cmd_pending(wdata, WIIPROTO_REQ_SREQ, 0))
+		wiimote_cmd_complete(wdata);
+}
+
+/* reduced generic report with "BB BB" key data only */
+static void handler_generic_K(struct wiimote_data *wdata, const __u8 *payload)
+{
+	handler_keys(wdata, payload);
+}
+
+static void handler_data(struct wiimote_data *wdata, const __u8 *payload)
+{
+	__u16 offset = payload[3] << 8 | payload[4];
+	__u8 size = (payload[2] >> 4) + 1;
+	__u8 err = payload[2] & 0x0f;
+
+	handler_keys(wdata, payload);
+
+	if (wiimote_cmd_pending(wdata, WIIPROTO_REQ_RMEM, offset)) {
+		if (err)
+			size = 0;
+		else if (size > wdata->state.cmd_read_size)
+			size = wdata->state.cmd_read_size;
+
+		wdata->state.cmd_read_size = size;
+		if (wdata->state.cmd_read_buf)
+			memcpy(wdata->state.cmd_read_buf, &payload[5], size);
+		wiimote_cmd_complete(wdata);
+	}
+}
+
+static void handler_return(struct wiimote_data *wdata, const __u8 *payload)
+{
+	__u8 err = payload[3];
+	__u8 cmd = payload[2];
+
+	handler_keys(wdata, payload);
+
+	if (wiimote_cmd_pending(wdata, cmd, 0)) {
+		wdata->state.cmd_err = err;
+		wiimote_cmd_complete(wdata);
+	} else if (err) {
+		hid_warn(wdata->hdev, "Remote error %hhu on req %hhu\n", err,
+									cmd);
+	}
+}
+
+static void handler_drm_KA(struct wiimote_data *wdata, const __u8 *payload)
+{
+	handler_keys(wdata, payload);
+	handler_accel(wdata, payload);
+}
+
+static void handler_drm_KE(struct wiimote_data *wdata, const __u8 *payload)
+{
+	handler_keys(wdata, payload);
+	handler_ext(wdata, &payload[2], 8);
+}
+
+static void handler_drm_KAI(struct wiimote_data *wdata, const __u8 *payload)
+{
+	handler_keys(wdata, payload);
+	handler_accel(wdata, payload);
+	ir_to_input0(wdata, &payload[5], false);
+	ir_to_input1(wdata, &payload[8], false);
+	ir_to_input2(wdata, &payload[11], false);
+	ir_to_input3(wdata, &payload[14], false);
+}
+
+static void handler_drm_KEE(struct wiimote_data *wdata, const __u8 *payload)
+{
+	handler_keys(wdata, payload);
+	handler_ext(wdata, &payload[2], 19);
+}
+
+static void handler_drm_KIE(struct wiimote_data *wdata, const __u8 *payload)
+{
+	handler_keys(wdata, payload);
+	ir_to_input0(wdata, &payload[2], false);
+	ir_to_input1(wdata, &payload[4], true);
+	ir_to_input2(wdata, &payload[7], false);
+	ir_to_input3(wdata, &payload[9], true);
+	handler_ext(wdata, &payload[12], 9);
+}
+
+static void handler_drm_KAE(struct wiimote_data *wdata, const __u8 *payload)
+{
+	handler_keys(wdata, payload);
+	handler_accel(wdata, payload);
+	handler_ext(wdata, &payload[5], 16);
+}
+
+static void handler_drm_KAIE(struct wiimote_data *wdata, const __u8 *payload)
+{
+	handler_keys(wdata, payload);
+	handler_accel(wdata, payload);
+	ir_to_input0(wdata, &payload[5], false);
+	ir_to_input1(wdata, &payload[7], true);
+	ir_to_input2(wdata, &payload[10], false);
+	ir_to_input3(wdata, &payload[12], true);
+	handler_ext(wdata, &payload[15], 6);
+}
+
+static void handler_drm_E(struct wiimote_data *wdata, const __u8 *payload)
+{
+	handler_ext(wdata, payload, 21);
+}
+
+static void handler_drm_SKAI1(struct wiimote_data *wdata, const __u8 *payload)
+{
+	handler_keys(wdata, payload);
+
+	wdata->state.accel_split[0] = payload[2];
+	wdata->state.accel_split[1] = (payload[0] >> 1) & (0x10 | 0x20);
+	wdata->state.accel_split[1] |= (payload[1] << 1) & (0x40 | 0x80);
+
+	ir_to_input0(wdata, &payload[3], false);
+	ir_to_input1(wdata, &payload[12], false);
+}
+
+static void handler_drm_SKAI2(struct wiimote_data *wdata, const __u8 *payload)
+{
+	__u8 buf[5];
+
+	handler_keys(wdata, payload);
+
+	wdata->state.accel_split[1] |= (payload[0] >> 5) & (0x01 | 0x02);
+	wdata->state.accel_split[1] |= (payload[1] >> 3) & (0x04 | 0x08);
+
+	buf[0] = 0;
+	buf[1] = 0;
+	buf[2] = wdata->state.accel_split[0];
+	buf[3] = payload[2];
+	buf[4] = wdata->state.accel_split[1];
+	handler_accel(wdata, buf);
+
+	ir_to_input2(wdata, &payload[3], false);
+	ir_to_input3(wdata, &payload[12], false);
+}
+
+struct wiiproto_handler {
+	__u8 id;
+	size_t size;
+	void (*func)(struct wiimote_data *wdata, const __u8 *payload);
+};
+
+static const struct wiiproto_handler handlers[] = {
+	{ .id = WIIPROTO_REQ_STATUS, .size = 6, .func = handler_status },
+	{ .id = WIIPROTO_REQ_STATUS, .size = 2, .func = handler_status_K },
+	{ .id = WIIPROTO_REQ_DATA, .size = 21, .func = handler_data },
+	{ .id = WIIPROTO_REQ_DATA, .size = 2, .func = handler_generic_K },
+	{ .id = WIIPROTO_REQ_RETURN, .size = 4, .func = handler_return },
+	{ .id = WIIPROTO_REQ_RETURN, .size = 2, .func = handler_generic_K },
+	{ .id = WIIPROTO_REQ_DRM_K, .size = 2, .func = handler_keys },
+	{ .id = WIIPROTO_REQ_DRM_KA, .size = 5, .func = handler_drm_KA },
+	{ .id = WIIPROTO_REQ_DRM_KA, .size = 2, .func = handler_generic_K },
+	{ .id = WIIPROTO_REQ_DRM_KE, .size = 10, .func = handler_drm_KE },
+	{ .id = WIIPROTO_REQ_DRM_KE, .size = 2, .func = handler_generic_K },
+	{ .id = WIIPROTO_REQ_DRM_KAI, .size = 17, .func = handler_drm_KAI },
+	{ .id = WIIPROTO_REQ_DRM_KAI, .size = 2, .func = handler_generic_K },
+	{ .id = WIIPROTO_REQ_DRM_KEE, .size = 21, .func = handler_drm_KEE },
+	{ .id = WIIPROTO_REQ_DRM_KEE, .size = 2, .func = handler_generic_K },
+	{ .id = WIIPROTO_REQ_DRM_KAE, .size = 21, .func = handler_drm_KAE },
+	{ .id = WIIPROTO_REQ_DRM_KAE, .size = 2, .func = handler_generic_K },
+	{ .id = WIIPROTO_REQ_DRM_KIE, .size = 21, .func = handler_drm_KIE },
+	{ .id = WIIPROTO_REQ_DRM_KIE, .size = 2, .func = handler_generic_K },
+	{ .id = WIIPROTO_REQ_DRM_KAIE, .size = 21, .func = handler_drm_KAIE },
+	{ .id = WIIPROTO_REQ_DRM_KAIE, .size = 2, .func = handler_generic_K },
+	{ .id = WIIPROTO_REQ_DRM_E, .size = 21, .func = handler_drm_E },
+	{ .id = WIIPROTO_REQ_DRM_SKAI1, .size = 21, .func = handler_drm_SKAI1 },
+	{ .id = WIIPROTO_REQ_DRM_SKAI2, .size = 21, .func = handler_drm_SKAI2 },
+	{ .id = 0 }
+};
+
+static int wiimote_hid_event(struct hid_device *hdev, struct hid_report *report,
+							u8 *raw_data, int size)
+{
+	struct wiimote_data *wdata = hid_get_drvdata(hdev);
+	const struct wiiproto_handler *h;
+	int i;
+	unsigned long flags;
+
+	if (size < 1)
+		return -EINVAL;
+
+	for (i = 0; handlers[i].id; ++i) {
+		h = &handlers[i];
+		if (h->id == raw_data[0] && h->size < size) {
+			spin_lock_irqsave(&wdata->state.lock, flags);
+			h->func(wdata, &raw_data[1]);
+			spin_unlock_irqrestore(&wdata->state.lock, flags);
+			break;
+		}
+	}
+
+	if (!handlers[i].id)
+		hid_warn(hdev, "Unhandled report %hhu size %d\n", raw_data[0],
+									size);
+
+	return 0;
+}
+
+static ssize_t wiimote_ext_show(struct device *dev,
+				struct device_attribute *attr,
+				char *buf)
+{
+	struct wiimote_data *wdata = dev_to_wii(dev);
+	__u8 type;
+	unsigned long flags;
+
+	spin_lock_irqsave(&wdata->state.lock, flags);
+	type = wdata->state.exttype;
+	spin_unlock_irqrestore(&wdata->state.lock, flags);
+
+	switch (type) {
+	case WIIMOTE_EXT_NONE:
+		return sprintf(buf, "none\n");
+	case WIIMOTE_EXT_NUNCHUK:
+		return sprintf(buf, "nunchuk\n");
+	case WIIMOTE_EXT_CLASSIC_CONTROLLER:
+		return sprintf(buf, "classic\n");
+	case WIIMOTE_EXT_BALANCE_BOARD:
+		return sprintf(buf, "balanceboard\n");
+	case WIIMOTE_EXT_PRO_CONTROLLER:
+		return sprintf(buf, "procontroller\n");
+	case WIIMOTE_EXT_DRUMS:
+		return sprintf(buf, "drums\n");
+	case WIIMOTE_EXT_GUITAR:
+		return sprintf(buf, "guitar\n");
+	case WIIMOTE_EXT_UNKNOWN:
+	default:
+		return sprintf(buf, "unknown\n");
+	}
+}
+
+static ssize_t wiimote_ext_store(struct device *dev,
+				 struct device_attribute *attr,
+				 const char *buf, size_t count)
+{
+	struct wiimote_data *wdata = dev_to_wii(dev);
+
+	if (!strcmp(buf, "scan")) {
+		wiimote_schedule(wdata);
+	} else {
+		return -EINVAL;
+	}
+
+	return strnlen(buf, PAGE_SIZE);
+}
+
+static DEVICE_ATTR(extension, S_IRUGO | S_IWUSR | S_IWGRP, wiimote_ext_show,
+		   wiimote_ext_store);
+
+static ssize_t wiimote_dev_show(struct device *dev,
+				struct device_attribute *attr,
+				char *buf)
+{
+	struct wiimote_data *wdata = dev_to_wii(dev);
+	__u8 type;
+	unsigned long flags;
+
+	spin_lock_irqsave(&wdata->state.lock, flags);
+	type = wdata->state.devtype;
+	spin_unlock_irqrestore(&wdata->state.lock, flags);
+
+	switch (type) {
+	case WIIMOTE_DEV_GENERIC:
+		return sprintf(buf, "generic\n");
+	case WIIMOTE_DEV_GEN10:
+		return sprintf(buf, "gen10\n");
+	case WIIMOTE_DEV_GEN20:
+		return sprintf(buf, "gen20\n");
+	case WIIMOTE_DEV_BALANCE_BOARD:
+		return sprintf(buf, "balanceboard\n");
+	case WIIMOTE_DEV_PRO_CONTROLLER:
+		return sprintf(buf, "procontroller\n");
+	case WIIMOTE_DEV_PENDING:
+		return sprintf(buf, "pending\n");
+	case WIIMOTE_DEV_UNKNOWN:
+	default:
+		return sprintf(buf, "unknown\n");
+	}
+}
+
+static DEVICE_ATTR(devtype, S_IRUGO, wiimote_dev_show, NULL);
+
+static struct wiimote_data *wiimote_create(struct hid_device *hdev)
+{
+	struct wiimote_data *wdata;
+
+	wdata = kzalloc(sizeof(*wdata), GFP_KERNEL);
+	if (!wdata)
+		return NULL;
+
+	wdata->hdev = hdev;
+	hid_set_drvdata(hdev, wdata);
+
+	spin_lock_init(&wdata->queue.lock);
+	INIT_WORK(&wdata->queue.worker, wiimote_queue_worker);
+
+	spin_lock_init(&wdata->state.lock);
+	init_completion(&wdata->state.ready);
+	mutex_init(&wdata->state.sync);
+	wdata->state.drm = WIIPROTO_REQ_DRM_K;
+	wdata->state.cmd_battery = 0xff;
+
+	INIT_WORK(&wdata->init_worker, wiimote_init_worker);
+	timer_setup(&wdata->timer, wiimote_init_timeout, 0);
+
+	return wdata;
+}
+
+static void wiimote_destroy(struct wiimote_data *wdata)
+{
+	unsigned long flags;
+
+	wiidebug_deinit(wdata);
+
+	/* prevent init_worker from being scheduled again */
+	spin_lock_irqsave(&wdata->state.lock, flags);
+	wdata->state.flags |= WIIPROTO_FLAG_EXITING;
+	spin_unlock_irqrestore(&wdata->state.lock, flags);
+
+	cancel_work_sync(&wdata->init_worker);
+	del_timer_sync(&wdata->timer);
+
+	device_remove_file(&wdata->hdev->dev, &dev_attr_devtype);
+	device_remove_file(&wdata->hdev->dev, &dev_attr_extension);
+
+	wiimote_mp_unload(wdata);
+	wiimote_ext_unload(wdata);
+	wiimote_modules_unload(wdata);
+	cancel_work_sync(&wdata->queue.worker);
+	hid_hw_close(wdata->hdev);
+	hid_hw_stop(wdata->hdev);
+
+	kfree(wdata);
+}
+
+static int wiimote_hid_probe(struct hid_device *hdev,
+				const struct hid_device_id *id)
+{
+	struct wiimote_data *wdata;
+	int ret;
+
+	hdev->quirks |= HID_QUIRK_NO_INIT_REPORTS;
+
+	wdata = wiimote_create(hdev);
+	if (!wdata) {
+		hid_err(hdev, "Can't alloc device\n");
+		return -ENOMEM;
+	}
+
+	ret = hid_parse(hdev);
+	if (ret) {
+		hid_err(hdev, "HID parse failed\n");
+		goto err;
+	}
+
+	ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
+	if (ret) {
+		hid_err(hdev, "HW start failed\n");
+		goto err;
+	}
+
+	ret = hid_hw_open(hdev);
+	if (ret) {
+		hid_err(hdev, "cannot start hardware I/O\n");
+		goto err_stop;
+	}
+
+	ret = device_create_file(&hdev->dev, &dev_attr_extension);
+	if (ret) {
+		hid_err(hdev, "cannot create sysfs attribute\n");
+		goto err_close;
+	}
+
+	ret = device_create_file(&hdev->dev, &dev_attr_devtype);
+	if (ret) {
+		hid_err(hdev, "cannot create sysfs attribute\n");
+		goto err_ext;
+	}
+
+	ret = wiidebug_init(wdata);
+	if (ret)
+		goto err_free;
+
+	hid_info(hdev, "New device registered\n");
+
+	/* schedule device detection */
+	wiimote_schedule(wdata);
+
+	return 0;
+
+err_free:
+	wiimote_destroy(wdata);
+	return ret;
+
+err_ext:
+	device_remove_file(&wdata->hdev->dev, &dev_attr_extension);
+err_close:
+	hid_hw_close(hdev);
+err_stop:
+	hid_hw_stop(hdev);
+err:
+	input_free_device(wdata->ir);
+	input_free_device(wdata->accel);
+	kfree(wdata);
+	return ret;
+}
+
+static void wiimote_hid_remove(struct hid_device *hdev)
+{
+	struct wiimote_data *wdata = hid_get_drvdata(hdev);
+
+	hid_info(hdev, "Device removed\n");
+	wiimote_destroy(wdata);
+}
+
+static const struct hid_device_id wiimote_hid_devices[] = {
+	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_NINTENDO,
+				USB_DEVICE_ID_NINTENDO_WIIMOTE) },
+	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_NINTENDO,
+				USB_DEVICE_ID_NINTENDO_WIIMOTE2) },
+	{ }
+};
+
+bool wiimote_dpad_as_analog = false;
+module_param_named(dpad_as_analog, wiimote_dpad_as_analog, bool, 0644);
+MODULE_PARM_DESC(dpad_as_analog, "Use D-Pad as main analog input");
+
+MODULE_DEVICE_TABLE(hid, wiimote_hid_devices);
+
+static struct hid_driver wiimote_hid_driver = {
+	.name = "wiimote",
+	.id_table = wiimote_hid_devices,
+	.probe = wiimote_hid_probe,
+	.remove = wiimote_hid_remove,
+	.raw_event = wiimote_hid_event,
+};
+module_hid_driver(wiimote_hid_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("David Herrmann <dh.herrmann@gmail.com>");
+MODULE_DESCRIPTION("Driver for Nintendo Wii / Wii U peripherals");