xref: /linux/drivers/hid/hid-magicmouse.c (revision f8324e20f8289dffc646d64366332e05eaacab25)
1 /*
2  *   Apple "Magic" Wireless Mouse driver
3  *
4  *   Copyright (c) 2010 Michael Poole <mdpoole@troilus.org>
5  */
6 
7 /*
8  * This program is free software; you can redistribute it and/or modify it
9  * under the terms of the GNU General Public License as published by the Free
10  * Software Foundation; either version 2 of the License, or (at your option)
11  * any later version.
12  */
13 
14 #include <linux/device.h>
15 #include <linux/hid.h>
16 #include <linux/module.h>
17 #include <linux/slab.h>
18 #include <linux/usb.h>
19 
20 #include "hid-ids.h"
21 
22 static bool emulate_3button = true;
23 module_param(emulate_3button, bool, 0644);
24 MODULE_PARM_DESC(emulate_3button, "Emulate a middle button");
25 
26 static int middle_button_start = -350;
27 static int middle_button_stop = +350;
28 
29 static bool emulate_scroll_wheel = true;
30 module_param(emulate_scroll_wheel, bool, 0644);
31 MODULE_PARM_DESC(emulate_scroll_wheel, "Emulate a scroll wheel");
32 
33 static bool report_touches = true;
34 module_param(report_touches, bool, 0644);
35 MODULE_PARM_DESC(report_touches, "Emit touch records (otherwise, only use them for emulation)");
36 
37 static bool report_undeciphered;
38 module_param(report_undeciphered, bool, 0644);
39 MODULE_PARM_DESC(report_undeciphered, "Report undeciphered multi-touch state field using a MSC_RAW event");
40 
41 #define TOUCH_REPORT_ID   0x29
42 /* These definitions are not precise, but they're close enough.  (Bits
43  * 0x03 seem to indicate the aspect ratio of the touch, bits 0x70 seem
44  * to be some kind of bit mask -- 0x20 may be a near-field reading,
45  * and 0x40 is actual contact, and 0x10 may be a start/stop or change
46  * indication.)
47  */
48 #define TOUCH_STATE_MASK  0xf0
49 #define TOUCH_STATE_NONE  0x00
50 #define TOUCH_STATE_START 0x30
51 #define TOUCH_STATE_DRAG  0x40
52 
53 /**
54  * struct magicmouse_sc - Tracks Magic Mouse-specific data.
55  * @input: Input device through which we report events.
56  * @quirks: Currently unused.
57  * @last_timestamp: Timestamp from most recent (18-bit) touch report
58  *     (units of milliseconds over short windows, but seems to
59  *     increase faster when there are no touches).
60  * @delta_time: 18-bit difference between the two most recent touch
61  *     reports from the mouse.
62  * @ntouches: Number of touches in most recent touch report.
63  * @scroll_accel: Number of consecutive scroll motions.
64  * @scroll_jiffies: Time of last scroll motion.
65  * @touches: Most recent data for a touch, indexed by tracking ID.
66  * @tracking_ids: Mapping of current touch input data to @touches.
67  */
68 struct magicmouse_sc {
69 	struct input_dev *input;
70 	unsigned long quirks;
71 
72 	int last_timestamp;
73 	int delta_time;
74 	int ntouches;
75 	int scroll_accel;
76 	unsigned long scroll_jiffies;
77 
78 	struct {
79 		short x;
80 		short y;
81 		short scroll_y;
82 		u8 size;
83 	} touches[16];
84 	int tracking_ids[16];
85 };
86 
87 static int magicmouse_firm_touch(struct magicmouse_sc *msc)
88 {
89 	int touch = -1;
90 	int ii;
91 
92 	/* If there is only one "firm" touch, set touch to its
93 	 * tracking ID.
94 	 */
95 	for (ii = 0; ii < msc->ntouches; ii++) {
96 		int idx = msc->tracking_ids[ii];
97 		if (msc->touches[idx].size < 8) {
98 			/* Ignore this touch. */
99 		} else if (touch >= 0) {
100 			touch = -1;
101 			break;
102 		} else {
103 			touch = idx;
104 		}
105 	}
106 
107 	return touch;
108 }
109 
110 static void magicmouse_emit_buttons(struct magicmouse_sc *msc, int state)
111 {
112 	int last_state = test_bit(BTN_LEFT, msc->input->key) << 0 |
113 		test_bit(BTN_RIGHT, msc->input->key) << 1 |
114 		test_bit(BTN_MIDDLE, msc->input->key) << 2;
115 
116 	if (emulate_3button) {
117 		int id;
118 
119 		/* If some button was pressed before, keep it held
120 		 * down.  Otherwise, if there's exactly one firm
121 		 * touch, use that to override the mouse's guess.
122 		 */
123 		if (state == 0) {
124 			/* The button was released. */
125 		} else if (last_state != 0) {
126 			state = last_state;
127 		} else if ((id = magicmouse_firm_touch(msc)) >= 0) {
128 			int x = msc->touches[id].x;
129 			if (x < middle_button_start)
130 				state = 1;
131 			else if (x > middle_button_stop)
132 				state = 2;
133 			else
134 				state = 4;
135 		} /* else: we keep the mouse's guess */
136 
137 		input_report_key(msc->input, BTN_MIDDLE, state & 4);
138 	}
139 
140 	input_report_key(msc->input, BTN_LEFT, state & 1);
141 	input_report_key(msc->input, BTN_RIGHT, state & 2);
142 
143 	if (state != last_state)
144 		msc->scroll_accel = 0;
145 }
146 
147 static void magicmouse_emit_touch(struct magicmouse_sc *msc, int raw_id, u8 *tdata)
148 {
149 	struct input_dev *input = msc->input;
150 	__s32 x_y = tdata[0] << 8 | tdata[1] << 16 | tdata[2] << 24;
151 	int misc = tdata[5] | tdata[6] << 8;
152 	int id = (misc >> 6) & 15;
153 	int x = x_y << 12 >> 20;
154 	int y = -(x_y >> 20);
155 
156 	/* Store tracking ID and other fields. */
157 	msc->tracking_ids[raw_id] = id;
158 	msc->touches[id].x = x;
159 	msc->touches[id].y = y;
160 	msc->touches[id].size = misc & 63;
161 
162 	/* If requested, emulate a scroll wheel by detecting small
163 	 * vertical touch motions along the middle of the mouse.
164 	 */
165 	if (emulate_scroll_wheel &&
166 	    middle_button_start < x && x < middle_button_stop) {
167 		static const int accel_profile[] = {
168 			256, 228, 192, 160, 128, 96, 64, 32,
169 		};
170 		unsigned long now = jiffies;
171 		int step = msc->touches[id].scroll_y - y;
172 
173 		/* Reset acceleration after half a second. */
174 		if (time_after(now, msc->scroll_jiffies + HZ / 2))
175 			msc->scroll_accel = 0;
176 
177 		/* Calculate and apply the scroll motion. */
178 		switch (tdata[7] & TOUCH_STATE_MASK) {
179 		case TOUCH_STATE_START:
180 			msc->touches[id].scroll_y = y;
181 			msc->scroll_accel = min_t(int, msc->scroll_accel + 1,
182 						ARRAY_SIZE(accel_profile) - 1);
183 			break;
184 		case TOUCH_STATE_DRAG:
185 			step = step / accel_profile[msc->scroll_accel];
186 			if (step != 0) {
187 				msc->touches[id].scroll_y = y;
188 				msc->scroll_jiffies = now;
189 				input_report_rel(input, REL_WHEEL, step);
190 			}
191 			break;
192 		}
193 	}
194 
195 	/* Generate the input events for this touch. */
196 	if (report_touches) {
197 		int orientation = (misc >> 10) - 32;
198 
199 		input_report_abs(input, ABS_MT_TRACKING_ID, id);
200 		input_report_abs(input, ABS_MT_TOUCH_MAJOR, tdata[3]);
201 		input_report_abs(input, ABS_MT_TOUCH_MINOR, tdata[4]);
202 		input_report_abs(input, ABS_MT_ORIENTATION, orientation);
203 		input_report_abs(input, ABS_MT_POSITION_X, x);
204 		input_report_abs(input, ABS_MT_POSITION_Y, y);
205 
206 		if (report_undeciphered)
207 			input_event(input, EV_MSC, MSC_RAW, tdata[7]);
208 
209 		input_mt_sync(input);
210 	}
211 }
212 
213 static int magicmouse_raw_event(struct hid_device *hdev,
214 		struct hid_report *report, u8 *data, int size)
215 {
216 	struct magicmouse_sc *msc = hid_get_drvdata(hdev);
217 	struct input_dev *input = msc->input;
218 	int x, y, ts, ii, clicks;
219 
220 	switch (data[0]) {
221 	case 0x10:
222 		if (size != 6)
223 			return 0;
224 		x = (__s16)(data[2] | data[3] << 8);
225 		y = (__s16)(data[4] | data[5] << 8);
226 		clicks = data[1];
227 		break;
228 	case TOUCH_REPORT_ID:
229 		/* Expect six bytes of prefix, and N*8 bytes of touch data. */
230 		if (size < 6 || ((size - 6) % 8) != 0)
231 			return 0;
232 		ts = data[3] >> 6 | data[4] << 2 | data[5] << 10;
233 		msc->delta_time = (ts - msc->last_timestamp) & 0x3ffff;
234 		msc->last_timestamp = ts;
235 		msc->ntouches = (size - 6) / 8;
236 		for (ii = 0; ii < msc->ntouches; ii++)
237 			magicmouse_emit_touch(msc, ii, data + ii * 8 + 6);
238 		/* When emulating three-button mode, it is important
239 		 * to have the current touch information before
240 		 * generating a click event.
241 		 */
242 		x = (signed char)data[1];
243 		y = (signed char)data[2];
244 		clicks = data[3];
245 		break;
246 	case 0x20: /* Theoretically battery status (0-100), but I have
247 		    * never seen it -- maybe it is only upon request.
248 		    */
249 	case 0x60: /* Unknown, maybe laser on/off. */
250 	case 0x61: /* Laser reflection status change.
251 		    * data[1]: 0 = spotted, 1 = lost
252 		    */
253 	default:
254 		return 0;
255 	}
256 
257 	magicmouse_emit_buttons(msc, clicks & 3);
258 	input_report_rel(input, REL_X, x);
259 	input_report_rel(input, REL_Y, y);
260 	input_sync(input);
261 	return 1;
262 }
263 
264 static int magicmouse_input_open(struct input_dev *dev)
265 {
266 	struct hid_device *hid = input_get_drvdata(dev);
267 
268 	return hid->ll_driver->open(hid);
269 }
270 
271 static void magicmouse_input_close(struct input_dev *dev)
272 {
273 	struct hid_device *hid = input_get_drvdata(dev);
274 
275 	hid->ll_driver->close(hid);
276 }
277 
278 static void magicmouse_setup_input(struct input_dev *input, struct hid_device *hdev)
279 {
280 	input_set_drvdata(input, hdev);
281 	input->event = hdev->ll_driver->hidinput_input_event;
282 	input->open = magicmouse_input_open;
283 	input->close = magicmouse_input_close;
284 
285 	input->name = hdev->name;
286 	input->phys = hdev->phys;
287 	input->uniq = hdev->uniq;
288 	input->id.bustype = hdev->bus;
289 	input->id.vendor = hdev->vendor;
290 	input->id.product = hdev->product;
291 	input->id.version = hdev->version;
292 	input->dev.parent = hdev->dev.parent;
293 
294 	__set_bit(EV_KEY, input->evbit);
295 	__set_bit(BTN_LEFT, input->keybit);
296 	__set_bit(BTN_RIGHT, input->keybit);
297 	if (emulate_3button)
298 		__set_bit(BTN_MIDDLE, input->keybit);
299 	__set_bit(BTN_TOOL_FINGER, input->keybit);
300 
301 	__set_bit(EV_REL, input->evbit);
302 	__set_bit(REL_X, input->relbit);
303 	__set_bit(REL_Y, input->relbit);
304 	if (emulate_scroll_wheel)
305 		__set_bit(REL_WHEEL, input->relbit);
306 
307 	if (report_touches) {
308 		__set_bit(EV_ABS, input->evbit);
309 
310 		input_set_abs_params(input, ABS_MT_TRACKING_ID, 0, 15, 0, 0);
311 		input_set_abs_params(input, ABS_MT_TOUCH_MAJOR, 0, 255, 4, 0);
312 		input_set_abs_params(input, ABS_MT_TOUCH_MINOR, 0, 255, 4, 0);
313 		input_set_abs_params(input, ABS_MT_ORIENTATION, -32, 31, 1, 0);
314 		input_set_abs_params(input, ABS_MT_POSITION_X, -1100, 1358,
315 				4, 0);
316 		/* Note: Touch Y position from the device is inverted relative
317 		 * to how pointer motion is reported (and relative to how USB
318 		 * HID recommends the coordinates work).  This driver keeps
319 		 * the origin at the same position, and just uses the additive
320 		 * inverse of the reported Y.
321 		 */
322 		input_set_abs_params(input, ABS_MT_POSITION_Y, -1589, 2047,
323 				4, 0);
324 	}
325 
326 	if (report_undeciphered) {
327 		__set_bit(EV_MSC, input->evbit);
328 		__set_bit(MSC_RAW, input->mscbit);
329 	}
330 }
331 
332 static int magicmouse_probe(struct hid_device *hdev,
333 	const struct hid_device_id *id)
334 {
335 	__u8 feature_1[] = { 0xd7, 0x01 };
336 	__u8 feature_2[] = { 0xf8, 0x01, 0x32 };
337 	struct input_dev *input;
338 	struct magicmouse_sc *msc;
339 	struct hid_report *report;
340 	int ret;
341 
342 	msc = kzalloc(sizeof(*msc), GFP_KERNEL);
343 	if (msc == NULL) {
344 		dev_err(&hdev->dev, "can't alloc magicmouse descriptor\n");
345 		return -ENOMEM;
346 	}
347 
348 	msc->quirks = id->driver_data;
349 	hid_set_drvdata(hdev, msc);
350 
351 	ret = hid_parse(hdev);
352 	if (ret) {
353 		dev_err(&hdev->dev, "magicmouse hid parse failed\n");
354 		goto err_free;
355 	}
356 
357 	ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
358 	if (ret) {
359 		dev_err(&hdev->dev, "magicmouse hw start failed\n");
360 		goto err_free;
361 	}
362 
363 	/* we are handling the input ourselves */
364 	hidinput_disconnect(hdev);
365 
366 	report = hid_register_report(hdev, HID_INPUT_REPORT, TOUCH_REPORT_ID);
367 	if (!report) {
368 		dev_err(&hdev->dev, "unable to register touch report\n");
369 		ret = -ENOMEM;
370 		goto err_stop_hw;
371 	}
372 	report->size = 6;
373 
374 	ret = hdev->hid_output_raw_report(hdev, feature_1, sizeof(feature_1),
375 			HID_FEATURE_REPORT);
376 	if (ret != sizeof(feature_1)) {
377 		dev_err(&hdev->dev, "unable to request touch data (1:%d)\n",
378 				ret);
379 		goto err_stop_hw;
380 	}
381 	ret = hdev->hid_output_raw_report(hdev, feature_2,
382 			sizeof(feature_2), HID_FEATURE_REPORT);
383 	if (ret != sizeof(feature_2)) {
384 		dev_err(&hdev->dev, "unable to request touch data (2:%d)\n",
385 				ret);
386 		goto err_stop_hw;
387 	}
388 
389 	input = input_allocate_device();
390 	if (!input) {
391 		dev_err(&hdev->dev, "can't alloc input device\n");
392 		ret = -ENOMEM;
393 		goto err_stop_hw;
394 	}
395 	magicmouse_setup_input(input, hdev);
396 
397 	ret = input_register_device(input);
398 	if (ret) {
399 		dev_err(&hdev->dev, "input device registration failed\n");
400 		goto err_input;
401 	}
402 	msc->input = input;
403 
404 	return 0;
405 err_input:
406 	input_free_device(input);
407 err_stop_hw:
408 	hid_hw_stop(hdev);
409 err_free:
410 	kfree(msc);
411 	return ret;
412 }
413 
414 static void magicmouse_remove(struct hid_device *hdev)
415 {
416 	struct magicmouse_sc *msc = hid_get_drvdata(hdev);
417 
418 	hid_hw_stop(hdev);
419 	input_unregister_device(msc->input);
420 	kfree(msc);
421 }
422 
423 static const struct hid_device_id magic_mice[] = {
424 	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_MAGICMOUSE),
425 		.driver_data = 0 },
426 	{ }
427 };
428 MODULE_DEVICE_TABLE(hid, magic_mice);
429 
430 static struct hid_driver magicmouse_driver = {
431 	.name = "magicmouse",
432 	.id_table = magic_mice,
433 	.probe = magicmouse_probe,
434 	.remove = magicmouse_remove,
435 	.raw_event = magicmouse_raw_event,
436 };
437 
438 static int __init magicmouse_init(void)
439 {
440 	int ret;
441 
442 	ret = hid_register_driver(&magicmouse_driver);
443 	if (ret)
444 		printk(KERN_ERR "can't register magicmouse driver\n");
445 
446 	return ret;
447 }
448 
449 static void __exit magicmouse_exit(void)
450 {
451 	hid_unregister_driver(&magicmouse_driver);
452 }
453 
454 module_init(magicmouse_init);
455 module_exit(magicmouse_exit);
456 MODULE_LICENSE("GPL");
457