xref: /linux/drivers/hid/hid-magicmouse.c (revision 5499b45190237ca90dd2ac86395cf464fe1f4cc7)
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/usb.h>
18 
19 #include "hid-ids.h"
20 
21 static bool emulate_3button = true;
22 module_param(emulate_3button, bool, 0644);
23 MODULE_PARM_DESC(emulate_3button, "Emulate a middle button");
24 
25 static int middle_button_start = -350;
26 static int middle_button_stop = +350;
27 
28 static bool emulate_scroll_wheel = true;
29 module_param(emulate_scroll_wheel, bool, 0644);
30 MODULE_PARM_DESC(emulate_scroll_wheel, "Emulate a scroll wheel");
31 
32 static bool report_touches = true;
33 module_param(report_touches, bool, 0644);
34 MODULE_PARM_DESC(report_touches, "Emit touch records (otherwise, only use them for emulation)");
35 
36 static bool report_undeciphered;
37 module_param(report_undeciphered, bool, 0644);
38 MODULE_PARM_DESC(report_undeciphered, "Report undeciphered multi-touch state field using a MSC_RAW event");
39 
40 #define TOUCH_REPORT_ID   0x29
41 /* These definitions are not precise, but they're close enough.  (Bits
42  * 0x03 seem to indicate the aspect ratio of the touch, bits 0x70 seem
43  * to be some kind of bit mask -- 0x20 may be a near-field reading,
44  * and 0x40 is actual contact, and 0x10 may be a start/stop or change
45  * indication.)
46  */
47 #define TOUCH_STATE_MASK  0xf0
48 #define TOUCH_STATE_NONE  0x00
49 #define TOUCH_STATE_START 0x30
50 #define TOUCH_STATE_DRAG  0x40
51 
52 /**
53  * struct magicmouse_sc - Tracks Magic Mouse-specific data.
54  * @input: Input device through which we report events.
55  * @quirks: Currently unused.
56  * @last_timestamp: Timestamp from most recent (18-bit) touch report
57  *     (units of milliseconds over short windows, but seems to
58  *     increase faster when there are no touches).
59  * @delta_time: 18-bit difference between the two most recent touch
60  *     reports from the mouse.
61  * @ntouches: Number of touches in most recent touch report.
62  * @scroll_accel: Number of consecutive scroll motions.
63  * @scroll_jiffies: Time of last scroll motion.
64  * @touches: Most recent data for a touch, indexed by tracking ID.
65  * @tracking_ids: Mapping of current touch input data to @touches.
66  */
67 struct magicmouse_sc {
68 	struct input_dev *input;
69 	unsigned long quirks;
70 
71 	int last_timestamp;
72 	int delta_time;
73 	int ntouches;
74 	int scroll_accel;
75 	unsigned long scroll_jiffies;
76 
77 	struct {
78 		short x;
79 		short y;
80 		short scroll_y;
81 		u8 size;
82 	} touches[16];
83 	int tracking_ids[16];
84 };
85 
86 static int magicmouse_firm_touch(struct magicmouse_sc *msc)
87 {
88 	int touch = -1;
89 	int ii;
90 
91 	/* If there is only one "firm" touch, set touch to its
92 	 * tracking ID.
93 	 */
94 	for (ii = 0; ii < msc->ntouches; ii++) {
95 		int idx = msc->tracking_ids[ii];
96 		if (msc->touches[idx].size < 8) {
97 			/* Ignore this touch. */
98 		} else if (touch >= 0) {
99 			touch = -1;
100 			break;
101 		} else {
102 			touch = idx;
103 		}
104 	}
105 
106 	return touch;
107 }
108 
109 static void magicmouse_emit_buttons(struct magicmouse_sc *msc, int state)
110 {
111 	int last_state = test_bit(BTN_LEFT, msc->input->key) << 0 |
112 		test_bit(BTN_RIGHT, msc->input->key) << 1 |
113 		test_bit(BTN_MIDDLE, msc->input->key) << 2;
114 
115 	if (emulate_3button) {
116 		int id;
117 
118 		/* If some button was pressed before, keep it held
119 		 * down.  Otherwise, if there's exactly one firm
120 		 * touch, use that to override the mouse's guess.
121 		 */
122 		if (state == 0) {
123 			/* The button was released. */
124 		} else if (last_state != 0) {
125 			state = last_state;
126 		} else if ((id = magicmouse_firm_touch(msc)) >= 0) {
127 			int x = msc->touches[id].x;
128 			if (x < middle_button_start)
129 				state = 1;
130 			else if (x > middle_button_stop)
131 				state = 2;
132 			else
133 				state = 4;
134 		} /* else: we keep the mouse's guess */
135 
136 		input_report_key(msc->input, BTN_MIDDLE, state & 4);
137 	}
138 
139 	input_report_key(msc->input, BTN_LEFT, state & 1);
140 	input_report_key(msc->input, BTN_RIGHT, state & 2);
141 
142 	if (state != last_state)
143 		msc->scroll_accel = 0;
144 }
145 
146 static void magicmouse_emit_touch(struct magicmouse_sc *msc, int raw_id, u8 *tdata)
147 {
148 	struct input_dev *input = msc->input;
149 	__s32 x_y = tdata[0] << 8 | tdata[1] << 16 | tdata[2] << 24;
150 	int misc = tdata[5] | tdata[6] << 8;
151 	int id = (misc >> 6) & 15;
152 	int x = x_y << 12 >> 20;
153 	int y = -(x_y >> 20);
154 
155 	/* Store tracking ID and other fields. */
156 	msc->tracking_ids[raw_id] = id;
157 	msc->touches[id].x = x;
158 	msc->touches[id].y = y;
159 	msc->touches[id].size = misc & 63;
160 
161 	/* If requested, emulate a scroll wheel by detecting small
162 	 * vertical touch motions along the middle of the mouse.
163 	 */
164 	if (emulate_scroll_wheel &&
165 	    middle_button_start < x && x < middle_button_stop) {
166 		static const int accel_profile[] = {
167 			256, 228, 192, 160, 128, 96, 64, 32,
168 		};
169 		unsigned long now = jiffies;
170 		int step = msc->touches[id].scroll_y - y;
171 
172 		/* Reset acceleration after half a second. */
173 		if (time_after(now, msc->scroll_jiffies + HZ / 2))
174 			msc->scroll_accel = 0;
175 
176 		/* Calculate and apply the scroll motion. */
177 		switch (tdata[7] & TOUCH_STATE_MASK) {
178 		case TOUCH_STATE_START:
179 			msc->touches[id].scroll_y = y;
180 			msc->scroll_accel = min_t(int, msc->scroll_accel + 1,
181 						ARRAY_SIZE(accel_profile) - 1);
182 			break;
183 		case TOUCH_STATE_DRAG:
184 			step = step / accel_profile[msc->scroll_accel];
185 			if (step != 0) {
186 				msc->touches[id].scroll_y = y;
187 				msc->scroll_jiffies = now;
188 				input_report_rel(input, REL_WHEEL, step);
189 			}
190 			break;
191 		}
192 	}
193 
194 	/* Generate the input events for this touch. */
195 	if (report_touches) {
196 		int orientation = (misc >> 10) - 32;
197 
198 		input_report_abs(input, ABS_MT_TRACKING_ID, id);
199 		input_report_abs(input, ABS_MT_TOUCH_MAJOR, tdata[3]);
200 		input_report_abs(input, ABS_MT_TOUCH_MINOR, tdata[4]);
201 		input_report_abs(input, ABS_MT_ORIENTATION, orientation);
202 		input_report_abs(input, ABS_MT_POSITION_X, x);
203 		input_report_abs(input, ABS_MT_POSITION_Y, y);
204 
205 		if (report_undeciphered)
206 			input_event(input, EV_MSC, MSC_RAW, tdata[7]);
207 
208 		input_mt_sync(input);
209 	}
210 }
211 
212 static int magicmouse_raw_event(struct hid_device *hdev,
213 		struct hid_report *report, u8 *data, int size)
214 {
215 	struct magicmouse_sc *msc = hid_get_drvdata(hdev);
216 	struct input_dev *input = msc->input;
217 	int x, y, ts, ii, clicks;
218 
219 	switch (data[0]) {
220 	case 0x10:
221 		if (size != 6)
222 			return 0;
223 		x = (__s16)(data[2] | data[3] << 8);
224 		y = (__s16)(data[4] | data[5] << 8);
225 		clicks = data[1];
226 		break;
227 	case TOUCH_REPORT_ID:
228 		/* Expect six bytes of prefix, and N*8 bytes of touch data. */
229 		if (size < 6 || ((size - 6) % 8) != 0)
230 			return 0;
231 		ts = data[3] >> 6 | data[4] << 2 | data[5] << 10;
232 		msc->delta_time = (ts - msc->last_timestamp) & 0x3ffff;
233 		msc->last_timestamp = ts;
234 		msc->ntouches = (size - 6) / 8;
235 		for (ii = 0; ii < msc->ntouches; ii++)
236 			magicmouse_emit_touch(msc, ii, data + ii * 8 + 6);
237 		/* When emulating three-button mode, it is important
238 		 * to have the current touch information before
239 		 * generating a click event.
240 		 */
241 		x = (signed char)data[1];
242 		y = (signed char)data[2];
243 		clicks = data[3];
244 		break;
245 	case 0x20: /* Theoretically battery status (0-100), but I have
246 		    * never seen it -- maybe it is only upon request.
247 		    */
248 	case 0x60: /* Unknown, maybe laser on/off. */
249 	case 0x61: /* Laser reflection status change.
250 		    * data[1]: 0 = spotted, 1 = lost
251 		    */
252 	default:
253 		return 0;
254 	}
255 
256 	magicmouse_emit_buttons(msc, clicks & 3);
257 	input_report_rel(input, REL_X, x);
258 	input_report_rel(input, REL_Y, y);
259 	input_sync(input);
260 	return 1;
261 }
262 
263 static int magicmouse_input_open(struct input_dev *dev)
264 {
265 	struct hid_device *hid = input_get_drvdata(dev);
266 
267 	return hid->ll_driver->open(hid);
268 }
269 
270 static void magicmouse_input_close(struct input_dev *dev)
271 {
272 	struct hid_device *hid = input_get_drvdata(dev);
273 
274 	hid->ll_driver->close(hid);
275 }
276 
277 static void magicmouse_setup_input(struct input_dev *input, struct hid_device *hdev)
278 {
279 	input_set_drvdata(input, hdev);
280 	input->event = hdev->ll_driver->hidinput_input_event;
281 	input->open = magicmouse_input_open;
282 	input->close = magicmouse_input_close;
283 
284 	input->name = hdev->name;
285 	input->phys = hdev->phys;
286 	input->uniq = hdev->uniq;
287 	input->id.bustype = hdev->bus;
288 	input->id.vendor = hdev->vendor;
289 	input->id.product = hdev->product;
290 	input->id.version = hdev->version;
291 	input->dev.parent = hdev->dev.parent;
292 
293 	__set_bit(EV_KEY, input->evbit);
294 	__set_bit(BTN_LEFT, input->keybit);
295 	__set_bit(BTN_RIGHT, input->keybit);
296 	if (emulate_3button)
297 		__set_bit(BTN_MIDDLE, input->keybit);
298 	__set_bit(BTN_TOOL_FINGER, input->keybit);
299 
300 	__set_bit(EV_REL, input->evbit);
301 	__set_bit(REL_X, input->relbit);
302 	__set_bit(REL_Y, input->relbit);
303 	if (emulate_scroll_wheel)
304 		__set_bit(REL_WHEEL, input->relbit);
305 
306 	if (report_touches) {
307 		__set_bit(EV_ABS, input->evbit);
308 
309 		input_set_abs_params(input, ABS_MT_TRACKING_ID, 0, 15, 0, 0);
310 		input_set_abs_params(input, ABS_MT_TOUCH_MAJOR, 0, 255, 4, 0);
311 		input_set_abs_params(input, ABS_MT_TOUCH_MINOR, 0, 255, 4, 0);
312 		input_set_abs_params(input, ABS_MT_ORIENTATION, -32, 31, 1, 0);
313 		input_set_abs_params(input, ABS_MT_POSITION_X, -1100, 1358,
314 				4, 0);
315 		/* Note: Touch Y position from the device is inverted relative
316 		 * to how pointer motion is reported (and relative to how USB
317 		 * HID recommends the coordinates work).  This driver keeps
318 		 * the origin at the same position, and just uses the additive
319 		 * inverse of the reported Y.
320 		 */
321 		input_set_abs_params(input, ABS_MT_POSITION_Y, -1589, 2047,
322 				4, 0);
323 	}
324 
325 	if (report_undeciphered) {
326 		__set_bit(EV_MSC, input->evbit);
327 		__set_bit(MSC_RAW, input->mscbit);
328 	}
329 }
330 
331 static int magicmouse_probe(struct hid_device *hdev,
332 	const struct hid_device_id *id)
333 {
334 	__u8 feature_1[] = { 0xd7, 0x01 };
335 	__u8 feature_2[] = { 0xf8, 0x01, 0x32 };
336 	struct input_dev *input;
337 	struct magicmouse_sc *msc;
338 	struct hid_report *report;
339 	int ret;
340 
341 	msc = kzalloc(sizeof(*msc), GFP_KERNEL);
342 	if (msc == NULL) {
343 		dev_err(&hdev->dev, "can't alloc magicmouse descriptor\n");
344 		return -ENOMEM;
345 	}
346 
347 	msc->quirks = id->driver_data;
348 	hid_set_drvdata(hdev, msc);
349 
350 	ret = hid_parse(hdev);
351 	if (ret) {
352 		dev_err(&hdev->dev, "magicmouse hid parse failed\n");
353 		goto err_free;
354 	}
355 
356 	ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
357 	if (ret) {
358 		dev_err(&hdev->dev, "magicmouse hw start failed\n");
359 		goto err_free;
360 	}
361 
362 	report = hid_register_report(hdev, HID_INPUT_REPORT, TOUCH_REPORT_ID);
363 	if (!report) {
364 		dev_err(&hdev->dev, "unable to register touch report\n");
365 		ret = -ENOMEM;
366 		goto err_stop_hw;
367 	}
368 	report->size = 6;
369 
370 	ret = hdev->hid_output_raw_report(hdev, feature_1, sizeof(feature_1),
371 			HID_FEATURE_REPORT);
372 	if (ret != sizeof(feature_1)) {
373 		dev_err(&hdev->dev, "unable to request touch data (1:%d)\n",
374 				ret);
375 		goto err_stop_hw;
376 	}
377 	ret = hdev->hid_output_raw_report(hdev, feature_2,
378 			sizeof(feature_2), HID_FEATURE_REPORT);
379 	if (ret != sizeof(feature_2)) {
380 		dev_err(&hdev->dev, "unable to request touch data (2:%d)\n",
381 				ret);
382 		goto err_stop_hw;
383 	}
384 
385 	input = input_allocate_device();
386 	if (!input) {
387 		dev_err(&hdev->dev, "can't alloc input device\n");
388 		ret = -ENOMEM;
389 		goto err_stop_hw;
390 	}
391 	magicmouse_setup_input(input, hdev);
392 
393 	ret = input_register_device(input);
394 	if (ret) {
395 		dev_err(&hdev->dev, "input device registration failed\n");
396 		goto err_input;
397 	}
398 	msc->input = input;
399 
400 	return 0;
401 err_input:
402 	input_free_device(input);
403 err_stop_hw:
404 	hid_hw_stop(hdev);
405 err_free:
406 	kfree(msc);
407 	return ret;
408 }
409 
410 static void magicmouse_remove(struct hid_device *hdev)
411 {
412 	hid_hw_stop(hdev);
413 	kfree(hid_get_drvdata(hdev));
414 }
415 
416 static const struct hid_device_id magic_mice[] = {
417 	{ HID_BLUETOOTH_DEVICE(USB_VENDOR_ID_APPLE, USB_DEVICE_ID_APPLE_MAGICMOUSE),
418 		.driver_data = 0 },
419 	{ }
420 };
421 MODULE_DEVICE_TABLE(hid, magic_mice);
422 
423 static struct hid_driver magicmouse_driver = {
424 	.name = "magicmouse",
425 	.id_table = magic_mice,
426 	.probe = magicmouse_probe,
427 	.remove = magicmouse_remove,
428 	.raw_event = magicmouse_raw_event,
429 };
430 
431 static int __init magicmouse_init(void)
432 {
433 	int ret;
434 
435 	ret = hid_register_driver(&magicmouse_driver);
436 	if (ret)
437 		printk(KERN_ERR "can't register magicmouse driver\n");
438 
439 	return ret;
440 }
441 
442 static void __exit magicmouse_exit(void)
443 {
444 	hid_unregister_driver(&magicmouse_driver);
445 }
446 
447 module_init(magicmouse_init);
448 module_exit(magicmouse_exit);
449 MODULE_LICENSE("GPL");
450