aboutsummaryrefslogtreecommitdiff
path: root/drivers/hid/hid-magicmouse.c
blob: 7cf3ffe4b7bc26f4eeda3f2167c1f88f6e46e29b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
/*
 *   Apple "Magic" Wireless Mouse driver
 *
 *   Copyright (c) 2010 Michael Poole <mdpoole@troilus.org>
 *   Copyright (c) 2010 Chase Douglas <chase.douglas@canonical.com>
 */

/*
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2 of the License, or (at your option)
 * any later version.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/device.h>
#include <linux/hid.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/usb.h>

#include "hid-ids.h"

static bool emulate_3button = true;
module_param(emulate_3button, bool, 0644);
MODULE_PARM_DESC(emulate_3button, "Emulate a middle button");

static int middle_button_start = -350;
static int middle_button_stop = +350;

static bool emulate_scroll_wheel = true;
module_param(emulate_scroll_wheel, bool, 0644);
MODULE_PARM_DESC(emulate_scroll_wheel, "Emulate a scroll wheel");

static unsigned int scroll_speed = 32;
static int param_set_scroll_speed(const char *val, struct kernel_param *kp) {
	unsigned long speed;
	if (!val || strict_strtoul(val, 0, &speed) || speed > 63)
		return -EINVAL;
	scroll_speed = speed;
	return 0;
}
module_param_call(scroll_speed, param_set_scroll_speed, param_get_uint, &scroll_speed, 0644);
MODULE_PARM_DESC(scroll_speed, "Scroll speed, value from 0 (slow) to 63 (fast)");

static bool scroll_acceleration = false;
module_param(scroll_acceleration, bool, 0644);
MODULE_PARM_DESC(scroll_acceleration, "Accelerate sequential scroll events");

static bool report_touches = true;
module_param(report_touches, bool, 0644);
MODULE_PARM_DESC(report_touches, "Emit touch records (otherwise, only use them for emulation)");

static bool report_undeciphered;
module_param(report_undeciphered, bool, 0644);
MODULE_PARM_DESC(report_undeciphered, "Report undeciphered multi-touch state field using a MSC_RAW event");

#define TRACKPAD_REPORT_ID 0x28
#define MOUSE_REPORT_ID    0x29
#define DOUBLE_REPORT_ID   0xf7
/* These definitions are not precise, but they're close enough.  (Bits
 * 0x03 seem to indicate the aspect ratio of the touch, bits 0x70 seem
 * to be some kind of bit mask -- 0x20 may be a near-field reading,
 * and 0x40 is actual contact, and 0x10 may be a start/stop or change
 * indication.)
 */
#define TOUCH_STATE_MASK  0xf0
#define TOUCH_STATE_NONE  0x00
#define TOUCH_STATE_START 0x30
#define TOUCH_STATE_DRAG  0x40

#define SCROLL_ACCEL_DEFAULT 7

/* Single touch emulation should only begin when no touches are currently down.
 * This is true when single_touch_id is equal to NO_TOUCHES. If multiple touches
 * are down and the touch providing for single touch emulation is lifted,
 * single_touch_id is equal to SINGLE_TOUCH_UP. While single touch emulation is
 * occurring, single_touch_id corresponds with the tracking id of the touch used.
 */
#define NO_TOUCHES -1
#define SINGLE_TOUCH_UP -2

/* Touch surface information. Dimension is in hundredths of a mm, min and max
 * are in units. */
#define MOUSE_DIMENSION_X (float)9056
#define MOUSE_MIN_X -1100
#define MOUSE_MAX_X 1258
#define MOUSE_RES_X ((MOUSE_MAX_X - MOUSE_MIN_X) / (MOUSE_DIMENSION_X / 100))
#define MOUSE_DIMENSION_Y (float)5152
#define MOUSE_MIN_Y -1589
#define MOUSE_MAX_Y 2047
#define MOUSE_RES_Y ((MOUSE_MAX_Y - MOUSE_MIN_Y) / (MOUSE_DIMENSION_Y / 100))

#define TRACKPAD_DIMENSION_X (float)13000
#define TRACKPAD_MIN_X -2909
#define TRACKPAD_MAX_X 3167
#define TRACKPAD_RES_X \
	((TRACKPAD_MAX_X - TRACKPAD_MIN_X) / (TRACKPAD_DIMENSION_X / 100))
#define TRACKPAD_DIMENSION_Y (float)11000
#define TRACKPAD_MIN_Y -2456
#define TRACKPAD_MAX_Y 2565
#define TRACKPAD_RES_Y \
	((TRACKPAD_MAX_Y - TRACKPAD_MIN_Y) / (TRACKPAD_DIMENSION_Y / 100))

/**
 * struct magicmouse_sc - Tracks Magic Mouse-specific data.
 * @input: Input device through which we report events.
 * @quirks: Currently unused.
 * @ntouches: Number of touches in most recent touch report.
 * @scroll_accel: Number of consecutive scroll motions.
 * @scroll_jiffies: Time of last scroll motion.
 * @touches: Most recent data for a touch, indexed by tracking ID.
 * @tracking_ids: Mapping of current touch input data to @touches.
 */
struct magicmouse_sc {
	struct input_dev *input;
	unsigned long quirks;

	int ntouches;
	int scroll_accel;
	unsigned long scroll_jiffies;

	struct {
		short x;
		short y;
		short scroll_x;
		short scroll_y;
		u8 size;
	} touches[16];
	int tracking_ids[16];
	int single_touch_id;
};

static int magicmouse_firm_touch(struct magicmouse_sc *msc)
{
	int touch = -1;
	int ii;

	/* If there is only one "firm" touch, set touch to its
	 * tracking ID.
	 */
	for (ii = 0; ii < msc->ntouches; ii++) {
		int idx = msc->tracking_ids[ii];
		if (msc->touches[idx].size < 8) {
			/* Ignore this touch. */
		} else if (touch >= 0) {
			touch = -1;
			break;
		} else {
			touch = idx;
		}
	}

	return touch;
}

static void magicmouse_emit_buttons(struct magicmouse_sc *msc, int state)
{
	int last_state = test_bit(BTN_LEFT, msc->input->key) << 0 |
		test_bit(BTN_RIGHT, msc->input->key) << 1 |
		test_bit(BTN_MIDDLE, msc->input->key) << 2;

	if (emulate_3button) {
		int id;

		/* If some button was pressed before, keep it held
		 * down.  Otherwise, if there's exactly one firm
		 * touch, use that to override the mouse's guess.
		 */
		if (state == 0) {
			/* The button was released. */
		} else if (last_state != 0) {
			state = last_state;
		} else if ((id = magicmouse_firm_touch(msc)) >= 0) {
			int x = msc->touches[id].x;
			if (x < middle_button_start)
				state = 1;
			else if (x > middle_button_stop)
				state = 2;
			else
				state = 4;
		} /* else: we keep the mouse's guess */

		input_report_key(msc->input, BTN_MIDDLE, state & 4);
	}

	input_report_key(msc->input, BTN_LEFT, state & 1);
	input_report_key(msc->input, BTN_RIGHT, state & 2);

	if (state != last_state)
		msc->scroll_accel = SCROLL_ACCEL_DEFAULT;
}

static void magicmouse_emit_touch(struct magicmouse_sc *msc, int raw_id, u8 *tdata)
{
	struct input_dev *input = msc->input;
	int id, x, y, size, orientation, touch_major, touch_minor, state, down;

	if (input->id.product == USB_DEVICE_ID_APPLE_MAGICMOUSE) {
		id = (tdata[6] << 2 | tdata[5] >> 6) & 0xf;
		x = (tdata[1] << 28 | tdata[0] << 20) >> 20;
		y = -((tdata[2] << 24 | tdata[1] << 16) >> 20);
		size = tdata[5] & 0x3f;
		orientation = (tdata[6] >> 2) - 32;
		touch_major = tdata[3];
		touch_minor = tdata[4];
		state = tdata[7] & TOUCH_STATE_MASK;
		down = state != TOUCH_STATE_NONE;
	} else { /* USB_DEVICE_ID_APPLE_MAGICTRACKPAD */
		id = (tdata[7] << 2 | tdata[6] >> 6) & 0xf;
		x = (tdata[1] << 27 | tdata[0] << 19) >> 19;
		y = -((tdata[3] << 30 | tdata[2] << 22 | tdata[1] << 14) >> 19);
		size = tdata[6] & 0x3f;
		orientation = (tdata[7] >> 2) - 32;
		touch_major = tdata[4];
		touch_minor = tdata[5];
		state = tdata[8] & TOUCH_STATE_MASK;
		down = state != TOUCH_STATE_NONE;
	}

	/* Store tracking ID and other fields. */
	msc->tracking_ids[raw_id] = id;
	msc->touches[id].x = x;
	msc->touches[id].y = y;
	msc->touches[id].size = size;

	/* If requested, emulate a scroll wheel by detecting small
	 * vertical touch motions.
	 */
	if (emulate_scroll_wheel) {
		unsigned long now = jiffies;
		int step_x = msc->touches[id].scroll_x - x;
		int step_y = msc->touches[id].scroll_y - y;

		/* Calculate and apply the scroll motion. */
		switch (state) {
		case TOUCH_STATE_START:
			msc->touches[id].scroll_x = x;
			msc->touches[id].scroll_y = y;

			/* Reset acceleration after half a second. */
			if (scroll_acceleration && time_before(now,
						msc->scroll_jiffies + HZ / 2))
				msc->scroll_accel = max_t(int,
						msc->scroll_accel - 1, 1);
			else
				msc->scroll_accel = SCROLL_ACCEL_DEFAULT;

			break;
		case TOUCH_STATE_DRAG:
			step_x /= (64 - (int)scroll_speed) * msc->scroll_accel;
			if (step_x != 0) {
				msc->touches[id].scroll_x -= step_x *
					(64 - scroll_speed) * msc->scroll_accel;
				msc->scroll_jiffies = now;
				input_report_rel(input, REL_HWHEEL, -step_x);
			}

			step_y /= (64 - (int)scroll_speed) * msc->scroll_accel;
			if (step_y != 0) {
				msc->touches[id].scroll_y -= step_y *
					(64 - scroll_speed) * msc->scroll_accel;
				msc->scroll_jiffies = now;
				input_report_rel(input, REL_WHEEL, step_y);
			}
			break;
		}
	}

	if (down) {
		msc->ntouches++;
		if (msc->single_touch_id == NO_TOUCHES)
			msc->single_touch_id = id;
	} else if (msc->single_touch_id == id)
		msc->single_touch_id = SINGLE_TOUCH_UP;

	/* Generate the input events for this touch. */
	if (report_touches && down) {
		input_report_abs(input, ABS_MT_TRACKING_ID, id);
		input_report_abs(input, ABS_MT_TOUCH_MAJOR, touch_major << 2);
		input_report_abs(input, ABS_MT_TOUCH_MINOR, touch_minor << 2);
		input_report_abs(input, ABS_MT_ORIENTATION, -orientation);
		input_report_abs(input, ABS_MT_POSITION_X, x);
		input_report_abs(input, ABS_MT_POSITION_Y, y);

		if (report_undeciphered) {
			if (input->id.product == USB_DEVICE_ID_APPLE_MAGICMOUSE)
				input_event(input, EV_MSC, MSC_RAW, tdata[7]);
			else /* USB_DEVICE_ID_APPLE_MAGICTRACKPAD */
				input_event(input, EV_MSC, MSC_RAW, tdata[8]);
		}

		input_mt_sync(input);
	}
}

static int magicmouse_raw_event(struct hid_device *hdev,
		struct hid_report *report, u8 *data, int size)
{
	struct magicmouse_sc *msc = hid_get_drvdata(hdev);
	struct input_dev *input = msc->input;
	int x = 0, y = 0, ii, clicks = 0, npoints;

	switch (data[0]) {
	case TRACKPAD_REPORT_ID:
		/* Expect four bytes of prefix, and N*9 bytes of touch data. */
		if (size < 4 || ((size - 4) % 9) != 0)
			return 0;
		npoints = (size - 4) / 9;
		msc->ntouches = 0;
		for (ii = 0; ii < npoints; ii++)
			magicmouse_emit_touch(msc, ii, data + ii * 9 + 4);

		/* We don't need an MT sync here because trackpad emits a
		 * BTN_TOUCH event in a new frame when all touches are released.
		 */
		if (msc->ntouches == 0)
			msc->single_touch_id = NO_TOUCHES;

		clicks = data[1];

		/* The following bits provide a device specific timestamp. They
		 * are unused here.
		 *
		 * ts = data[1] >> 6 | data[2] << 2 | data[3] << 10;
		 */
		break;
	case MOUSE_REPORT_ID:
		/* Expect six bytes of prefix, and N*8 bytes of touch data. */
		if (size < 6 || ((size - 6) % 8) != 0)
			return 0;
		npoints = (size - 6) / 8;
		msc->ntouches = 0;
		for (ii = 0; ii < npoints; ii++)
			magicmouse_emit_touch(msc, ii, data + ii * 8 + 6);

		if (report_touches && msc->ntouches == 0)
			input_mt_sync(input);

		/* When emulating three-button mode, it is important
		 * to have the current touch information before
		 * generating a click event.
		 */
		x = (int)(((data[3] & 0x0c) << 28) | (data[1] << 22)) >> 22;
		y = (int)(((data[3] & 0x30) << 26) | (data[2] << 22)) >> 22;
		clicks = data[3];

		/* The following bits provide a device specific timestamp. They
		 * are unused here.
		 *
		 * ts = data[3] >> 6 | data[4] << 2 | data[5] << 10;
		 */
		break;
	case DOUBLE_REPORT_ID:
		/* Sometimes the trackpad sends two touch reports in one
		 * packet.
		 */
		magicmouse_raw_event(hdev, report, data + 2, data[1]);
		magicmouse_raw_event(hdev, report, data + 2 + data[1],
			size - 2 - data[1]);
		break;
	default:
		return 0;
	}

	if (input->id.product == USB_DEVICE_ID_APPLE_MAGICMOUSE) {
		magicmouse_emit_buttons(msc, clicks & 3);
		input_report_rel(input, REL_X, x);
		input_report_rel(input, REL_Y, y);
	} else { /* USB_DEVICE_ID_APPLE_MAGICTRACKPAD */
		input_report_key(input, BTN_MOUSE, clicks & 1);
		input_report_key(input, BTN_TOUCH, msc->ntouches > 0);
		input_report_key(input, BTN_TOOL_FINGER, msc->ntouches == 1);
		input_report_key(input, BTN_TOOL_DOUBLETAP, msc->ntouches == 2);
		input_report_key(input, BTN_TOOL_TRIPLETAP, msc->ntouches == 3);
		input_report_key(input, BTN_TOOL_QUADTAP, msc->ntouches == 4);
		if (msc->single_touch_id >= 0) {
			input_report_abs(input, ABS_X,
				msc->touches[msc->single_touch_id].x);
			input_report_abs(input, ABS_Y,
				msc->touches[msc->single_touch_id].y);
		}
	}

	input_sync(input);
	return 1;
}

static void magicmouse_setup_input(struct input_dev *input, struct hid_device *hdev)
{
	__set_bit(EV_KEY, input->evbit);

	if (input->id.product == USB_DEVICE_ID_APPLE_MAGICMOUSE) {
		__set_bit(BTN_LEFT, input->keybit);
		__set_bit(BTN_RIGHT, input->keybit);
		if (emulate_3button)
			__set_bit(BTN_MIDDLE, input->keybit);

		__set_bit(EV_REL, input->evbit);
		__set_bit(REL_X, input->relbit);
		__set_bit(REL_Y, input->relbit);
		if (emulate_scroll_wheel) {
			__set_bit(REL_WHEEL, input->relbit);
			__set_bit(REL_HWHEEL, input->relbit);
		}
	} else { /* USB_DEVICE_ID_APPLE_MAGICTRACKPAD */
		/* input->keybit is initialized with incorrect button info
		 * for Magic Trackpad. There really is only one physical
		 * button (BTN_LEFT == BTN_MOUSE). Make sure we don't
		 * advertise buttons that don't exist...
		 */
		__clear_bit(BTN_RIGHT, input->keybit);
		__clear_bit(BTN_MIDDLE, input->keybit);
		__set_bit(BTN_MOUSE, input->keybit);
		__set_bit(BTN_TOOL_FINGER, input->keybit);
		__set_bit(BTN_TOOL_DOUBLETAP, input->keybit);
		__set_bit(BTN_TOOL_TRIPLETAP, input->keybit);
		__set_bit(BTN_TOOL_QUADTAP, input->keybit);
		__set_bit(BTN_TOUCH, input->keybit);
		__set_bit(INPUT_PROP_POINTER, input->propbit);
		__set_bit(INPUT_PROP_BUTTONPAD, input->propbit);
	}

	if (report_touches) {
		__set_bit(EV_ABS, input->evbit);

		input_set_abs_params(input, ABS_MT_TRACKING_ID, 0, 15, 0, 0);
		input_set_abs_params(input, ABS_MT_TOUCH_MAJOR, 0, 255, 4, 0);
		input_set_abs_params(input, ABS_MT_TOUCH_MINOR, 0, 255, 4, 0);
		input_set_abs_params(input, ABS_MT_ORIENTATION, -31, 32, 1, 0);

		/* Note: Touch Y position from the device is inverted relative
		 * to how pointer motion is reported (and relative to how USB
		 * HID recommends the coordinates work).  This driver keeps
		 * the origin at the same position, and just uses the additive
		 * inverse of the reported Y.
		 */
		if (input->id.product == USB_DEVICE_ID_APPLE_MAGICMOUSE) {
			input_set_abs_params(input, ABS_MT_POSITION_X,
				MOUSE_MIN_X, MOUSE_MAX_X, 4, 0);
			input_set_abs_params(input, ABS_MT_POSITION_Y,
				MOUSE_MIN_Y, MOUSE_MAX_Y, 4, 0);

			input_abs_set_res(input, ABS_MT_POSITION_X,
				MOUSE_RES_X);
			input_abs_set_res(input, ABS_MT_POSITION_Y,
				MOUSE_RES_Y);
		} else { /* USB_DEVICE_ID_APPLE_MAGICTRACKPAD */
			input_set_abs_params(input, ABS_X, TRACKPAD_MIN_X,
				TRACKPAD_MAX_X, 4, 0);
			input_set_abs_params(input, ABS_Y, TRACKPAD_MIN_Y,
				TRACKPAD_MAX_Y, 4, 0);
			input_set_abs_params(input, ABS_MT_POSITION_X,
				TRACKPAD_MIN_X, TRACKPAD_MAX_X, 4, 0);
			input_set_abs_params(input, ABS_MT_POSITION_Y,
				TRACKPAD_MIN_Y, TRACKPAD_MAX_Y, 4, 0);

			input_abs_set_res(input, ABS_X, TRACKPAD_RES_X);
			input_abs_set_res(input, ABS_Y, TRACKPAD_RES_Y);
			input_abs_set_res(input, ABS_MT_POSITION_X,
				TRACKPAD_RES_X);
			input_abs_set_res(input, ABS_MT_POSITION_Y,
				TRACKPAD_RES_Y);
		}

		input_set_events_per_packet(input, 60);
	}

	if (report_undeciphered) {
		__set_bit(EV_MSC, input->evbit);
		__set_bit(MSC_RAW, input->mscbit);
	}
}

static int magicmouse_input_mapping(struct hid_device *hdev,
		struct hid_input *hi, struct hid_field *field,
		struct hid_usage *usage, unsigned long **bit, int *max)
{
	struct magicmouse_sc *msc = hid_get_drvdata(hdev);

	if (!msc->input)
		msc->input = hi->input;

	/* Magic Trackpad does not give relative data after switching to MT */
	if (hi->input->id.product == USB_DEVICE_ID_APPLE_MAGICTRACKPAD &&
	    field->flags & HID_MAIN_ITEM_RELATIVE)
		return -1;

	return 0;
}

static int magicmouse_probe(struct hid_device *hdev,
	const struct hid_device_id *id)
{
	__u8 feature[] = { 0xd7, 0x01 };
	struct magicmouse_sc *msc;
	struct hid_report *report;
	int ret;

	msc = kzalloc(sizeof(*msc), GFP_KERNEL);
	if (msc == NULL) {
		hid_err(hdev, "can't alloc magicmouse descriptor\n");
		return -ENOMEM;
	}

	msc->scroll_accel = SCROLL_ACCEL_DEFAULT;

	msc->quirks = id->driver_data;
	hid_set_drvdata(hdev, msc);

	msc->single_touch_id = NO_TOUCHES;

	ret = hid_parse(hdev);
	if (ret) {
		hid_err(hdev, "magicmouse hid parse failed\n");
		goto err_free;
	}

	ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
	if (ret) {
		hid_err(hdev, "magicmouse hw start failed\n");
		goto err_free;
	}

	/* We do this after hid-input is done parsing reports so that
	 * hid-input uses the most natural button and axis IDs.
	 */
	if (msc->input)
		magicmouse_setup_input(msc->input, hdev);

	if (id->product == USB_DEVICE_ID_APPLE_MAGICMOUSE)
		report = hid_register_report(hdev, HID_INPUT_REPORT,
			MOUSE_REPORT_ID);
	else { /* USB_DEVICE_ID_APPLE_MAGICTRACKPAD */
		report = hid_register_report(hdev, HID_INPUT_REPORT,
			TRACKPAD_REPORT_ID);
		report = hid_register_report(hdev, HID_INPUT_REPORT,
			DOUBLE_REPORT_ID);
	}

	if (!report) {
		hid_err(hdev, "unable to register touch report\n");
		ret = -ENOMEM;
		goto err_stop_hw;
	}
	report->size = 6;

	/*
	 * Some devices repond with 'invalid report id' when feature
	 * report switching it into multitouch mode is sent to it.
	 *
	 * This results in -EIO from the _raw low-level transport callback,
	 * but there seems to be no other way of switching the mode.
	 * Thus the super-ugly hacky success check below.
	 */
	ret = hdev->hid_output_raw_report(hdev, feature, sizeof(feature),
			HID_FEATURE_REPORT);
	if (ret != -EIO && ret != sizeof(feature)) {
		hid_err(hdev, "unable to request touch data (%d)\n", ret);
		goto err_stop_hw;
	}

	return 0;
err_stop_hw:
	hid_hw_stop(hdev);
err_free:
	kfree(msc);
	return ret;
}

static void magicmouse_remove(struct hid_device *hdev)
{
	struct magicmouse_sc *msc = hid_get_drvdata(hdev);

	hid_hw_stop(hdev);
	kfree(msc);
}

static const struct hid_device_id magic_mice[] = {
	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_APPLE,
		USB_DEVICE_ID_APPLE_MAGICMOUSE), .driver_data = 0 },
	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_APPLE,
		USB_DEVICE_ID_APPLE_MAGICTRACKPAD), .driver_data = 0 },
	{ }
};
MODULE_DEVICE_TABLE(hid, magic_mice);

static struct hid_driver magicmouse_driver = {
	.name = "magicmouse",
	.id_table = magic_mice,
	.probe = magicmouse_probe,
	.remove = magicmouse_remove,
	.raw_event = magicmouse_raw_event,
	.input_mapping = magicmouse_input_mapping,
};

static int __init magicmouse_init(void)
{
	int ret;

	ret = hid_register_driver(&magicmouse_driver);
	if (ret)
		pr_err("can't register magicmouse driver\n");

	return ret;
}

static void __exit magicmouse_exit(void)
{
	hid_unregister_driver(&magicmouse_driver);
}

module_init(magicmouse_init);
module_exit(magicmouse_exit);
MODULE_LICENSE("GPL");