1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * BYD TouchPad PS/2 mouse driver
4  *
5  * Copyright (C) 2015 Chris Diamand <chris@diamand.org>
6  * Copyright (C) 2015 Richard Pospesel
7  * Copyright (C) 2015 Tai Chi Minh Ralph Eastwood
8  * Copyright (C) 2015 Martin Wimpress
9  * Copyright (C) 2015 Jay Kuri
10  */
11 
12 #include <linux/delay.h>
13 #include <linux/input.h>
14 #include <linux/libps2.h>
15 #include <linux/serio.h>
16 #include <linux/slab.h>
17 
18 #include "psmouse.h"
19 #include "byd.h"
20 
21 /* PS2 Bits */
22 #define PS2_Y_OVERFLOW	BIT_MASK(7)
23 #define PS2_X_OVERFLOW	BIT_MASK(6)
24 #define PS2_Y_SIGN	BIT_MASK(5)
25 #define PS2_X_SIGN	BIT_MASK(4)
26 #define PS2_ALWAYS_1	BIT_MASK(3)
27 #define PS2_MIDDLE	BIT_MASK(2)
28 #define PS2_RIGHT	BIT_MASK(1)
29 #define PS2_LEFT	BIT_MASK(0)
30 
31 /*
32  * BYD pad constants
33  */
34 
35 /*
36  * True device resolution is unknown, however experiments show the
37  * resolution is about 111 units/mm.
38  * Absolute coordinate packets are in the range 0-255 for both X and Y
39  * we pick ABS_X/ABS_Y dimensions which are multiples of 256 and in
40  * the right ballpark given the touchpad's physical dimensions and estimate
41  * resolution per spec sheet, device active area dimensions are
42  * 101.6 x 60.1 mm.
43  */
44 #define BYD_PAD_WIDTH		11264
45 #define BYD_PAD_HEIGHT		6656
46 #define BYD_PAD_RESOLUTION	111
47 
48 /*
49  * Given the above dimensions, relative packets velocity is in multiples of
50  * 1 unit / 11 milliseconds.  We use this dt to estimate distance traveled
51  */
52 #define BYD_DT			11
53 /* Time in jiffies used to timeout various touch events (64 ms) */
54 #define BYD_TOUCH_TIMEOUT	msecs_to_jiffies(64)
55 
56 /* BYD commands reverse engineered from windows driver */
57 
58 /*
59  * Swipe gesture from off-pad to on-pad
60  *  0 : disable
61  *  1 : enable
62  */
63 #define BYD_CMD_SET_OFFSCREEN_SWIPE		0x10cc
64 /*
65  * Tap and drag delay time
66  *  0 : disable
67  *  1 - 8 : least to most delay
68  */
69 #define BYD_CMD_SET_TAP_DRAG_DELAY_TIME		0x10cf
70 /*
71  * Physical buttons function mapping
72  *  0 : enable
73  *  4 : normal
74  *  5 : left button custom command
75  *  6 : right button custom command
76  *  8 : disable
77  */
78 #define BYD_CMD_SET_PHYSICAL_BUTTONS		0x10d0
79 /*
80  * Absolute mode (1 byte X/Y resolution)
81  *  0 : disable
82  *  2 : enable
83  */
84 #define BYD_CMD_SET_ABSOLUTE_MODE		0x10d1
85 /*
86  * Two finger scrolling
87  *  1 : vertical
88  *  2 : horizontal
89  *  3 : vertical + horizontal
90  *  4 : disable
91  */
92 #define BYD_CMD_SET_TWO_FINGER_SCROLL		0x10d2
93 /*
94  * Handedness
95  *  1 : right handed
96  *  2 : left handed
97  */
98 #define BYD_CMD_SET_HANDEDNESS			0x10d3
99 /*
100  * Tap to click
101  *  1 : enable
102  *  2 : disable
103  */
104 #define BYD_CMD_SET_TAP				0x10d4
105 /*
106  * Tap and drag
107  *  1 : tap and hold to drag
108  *  2 : tap and hold to drag + lock
109  *  3 : disable
110  */
111 #define BYD_CMD_SET_TAP_DRAG			0x10d5
112 /*
113  * Touch sensitivity
114  *  1 - 7 : least to most sensitive
115  */
116 #define BYD_CMD_SET_TOUCH_SENSITIVITY		0x10d6
117 /*
118  * One finger scrolling
119  *  1 : vertical
120  *  2 : horizontal
121  *  3 : vertical + horizontal
122  *  4 : disable
123  */
124 #define BYD_CMD_SET_ONE_FINGER_SCROLL		0x10d7
125 /*
126  * One finger scrolling function
127  *  1 : free scrolling
128  *  2 : edge motion
129  *  3 : free scrolling + edge motion
130  *  4 : disable
131  */
132 #define BYD_CMD_SET_ONE_FINGER_SCROLL_FUNC	0x10d8
133 /*
134  * Sliding speed
135  *  1 - 5 : slowest to fastest
136  */
137 #define BYD_CMD_SET_SLIDING_SPEED		0x10da
138 /*
139  * Edge motion
140  *  1 : disable
141  *  2 : enable when dragging
142  *  3 : enable when dragging and pointing
143  */
144 #define BYD_CMD_SET_EDGE_MOTION			0x10db
145 /*
146  * Left edge region size
147  *  0 - 7 : smallest to largest width
148  */
149 #define BYD_CMD_SET_LEFT_EDGE_REGION		0x10dc
150 /*
151  * Top edge region size
152  *  0 - 9 : smallest to largest height
153  */
154 #define BYD_CMD_SET_TOP_EDGE_REGION		0x10dd
155 /*
156  * Disregard palm press as clicks
157  *  1 - 6 : smallest to largest
158  */
159 #define BYD_CMD_SET_PALM_CHECK			0x10de
160 /*
161  * Right edge region size
162  *  0 - 7 : smallest to largest width
163  */
164 #define BYD_CMD_SET_RIGHT_EDGE_REGION		0x10df
165 /*
166  * Bottom edge region size
167  *  0 - 9 : smallest to largest height
168  */
169 #define BYD_CMD_SET_BOTTOM_EDGE_REGION		0x10e1
170 /*
171  * Multitouch gestures
172  *  1 : enable
173  *  2 : disable
174  */
175 #define BYD_CMD_SET_MULTITOUCH			0x10e3
176 /*
177  * Edge motion speed
178  *  0 : control with finger pressure
179  *  1 - 9 : slowest to fastest
180  */
181 #define BYD_CMD_SET_EDGE_MOTION_SPEED		0x10e4
182 /*
183  * Two finger scolling function
184  *  0 : free scrolling
185  *  1 : free scrolling (with momentum)
186  *  2 : edge motion
187  *  3 : free scrolling (with momentum) + edge motion
188  *  4 : disable
189  */
190 #define BYD_CMD_SET_TWO_FINGER_SCROLL_FUNC	0x10e5
191 
192 /*
193  * The touchpad generates a mixture of absolute and relative packets, indicated
194  * by the last byte of each packet being set to one of the following:
195  */
196 #define BYD_PACKET_ABSOLUTE			0xf8
197 #define BYD_PACKET_RELATIVE			0x00
198 /* Multitouch gesture packets */
199 #define BYD_PACKET_PINCH_IN			0xd8
200 #define BYD_PACKET_PINCH_OUT			0x28
201 #define BYD_PACKET_ROTATE_CLOCKWISE		0x29
202 #define BYD_PACKET_ROTATE_ANTICLOCKWISE		0xd7
203 #define BYD_PACKET_TWO_FINGER_SCROLL_RIGHT	0x2a
204 #define BYD_PACKET_TWO_FINGER_SCROLL_DOWN	0x2b
205 #define BYD_PACKET_TWO_FINGER_SCROLL_UP		0xd5
206 #define BYD_PACKET_TWO_FINGER_SCROLL_LEFT	0xd6
207 #define BYD_PACKET_THREE_FINGER_SWIPE_RIGHT	0x2c
208 #define BYD_PACKET_THREE_FINGER_SWIPE_DOWN	0x2d
209 #define BYD_PACKET_THREE_FINGER_SWIPE_UP	0xd3
210 #define BYD_PACKET_THREE_FINGER_SWIPE_LEFT	0xd4
211 #define BYD_PACKET_FOUR_FINGER_DOWN		0x33
212 #define BYD_PACKET_FOUR_FINGER_UP		0xcd
213 #define BYD_PACKET_REGION_SCROLL_RIGHT		0x35
214 #define BYD_PACKET_REGION_SCROLL_DOWN		0x36
215 #define BYD_PACKET_REGION_SCROLL_UP		0xca
216 #define BYD_PACKET_REGION_SCROLL_LEFT		0xcb
217 #define BYD_PACKET_RIGHT_CORNER_CLICK		0xd2
218 #define BYD_PACKET_LEFT_CORNER_CLICK		0x2e
219 #define BYD_PACKET_LEFT_AND_RIGHT_CORNER_CLICK	0x2f
220 #define BYD_PACKET_ONTO_PAD_SWIPE_RIGHT		0x37
221 #define BYD_PACKET_ONTO_PAD_SWIPE_DOWN		0x30
222 #define BYD_PACKET_ONTO_PAD_SWIPE_UP		0xd0
223 #define BYD_PACKET_ONTO_PAD_SWIPE_LEFT		0xc9
224 
225 struct byd_data {
226 	struct timer_list timer;
227 	struct psmouse *psmouse;
228 	s32 abs_x;
229 	s32 abs_y;
230 	typeof(jiffies) last_touch_time;
231 	bool btn_left;
232 	bool btn_right;
233 	bool touch;
234 };
235 
byd_report_input(struct psmouse * psmouse)236 static void byd_report_input(struct psmouse *psmouse)
237 {
238 	struct byd_data *priv = psmouse->private;
239 	struct input_dev *dev = psmouse->dev;
240 
241 	input_report_key(dev, BTN_TOUCH, priv->touch);
242 	input_report_key(dev, BTN_TOOL_FINGER, priv->touch);
243 
244 	input_report_abs(dev, ABS_X, priv->abs_x);
245 	input_report_abs(dev, ABS_Y, priv->abs_y);
246 	input_report_key(dev, BTN_LEFT, priv->btn_left);
247 	input_report_key(dev, BTN_RIGHT, priv->btn_right);
248 
249 	input_sync(dev);
250 }
251 
byd_clear_touch(struct timer_list * t)252 static void byd_clear_touch(struct timer_list *t)
253 {
254 	struct byd_data *priv = from_timer(priv, t, timer);
255 	struct psmouse *psmouse = priv->psmouse;
256 
257 	serio_pause_rx(psmouse->ps2dev.serio);
258 	priv->touch = false;
259 
260 	byd_report_input(psmouse);
261 
262 	serio_continue_rx(psmouse->ps2dev.serio);
263 
264 	/*
265 	 * Move cursor back to center of pad when we lose touch - this
266 	 * specifically improves user experience when moving cursor with one
267 	 * finger, and pressing a button with another.
268 	 */
269 	priv->abs_x = BYD_PAD_WIDTH / 2;
270 	priv->abs_y = BYD_PAD_HEIGHT / 2;
271 }
272 
byd_process_byte(struct psmouse * psmouse)273 static psmouse_ret_t byd_process_byte(struct psmouse *psmouse)
274 {
275 	struct byd_data *priv = psmouse->private;
276 	u8 *pkt = psmouse->packet;
277 
278 	if (psmouse->pktcnt > 0 && !(pkt[0] & PS2_ALWAYS_1)) {
279 		psmouse_warn(psmouse, "Always_1 bit not 1. pkt[0] = %02x\n",
280 			     pkt[0]);
281 		return PSMOUSE_BAD_DATA;
282 	}
283 
284 	if (psmouse->pktcnt < psmouse->pktsize)
285 		return PSMOUSE_GOOD_DATA;
286 
287 	/* Otherwise, a full packet has been received */
288 	switch (pkt[3]) {
289 	case BYD_PACKET_ABSOLUTE:
290 		/* Only use absolute packets for the start of movement. */
291 		if (!priv->touch) {
292 			/* needed to detect tap */
293 			typeof(jiffies) tap_time =
294 				priv->last_touch_time + BYD_TOUCH_TIMEOUT;
295 			priv->touch = time_after(jiffies, tap_time);
296 
297 			/* init abs position */
298 			priv->abs_x = pkt[1] * (BYD_PAD_WIDTH / 256);
299 			priv->abs_y = (255 - pkt[2]) * (BYD_PAD_HEIGHT / 256);
300 		}
301 		break;
302 	case BYD_PACKET_RELATIVE: {
303 		/* Standard packet */
304 		/* Sign-extend if a sign bit is set. */
305 		u32 signx = pkt[0] & PS2_X_SIGN ? ~0xFF : 0;
306 		u32 signy = pkt[0] & PS2_Y_SIGN ? ~0xFF : 0;
307 		s32 dx = signx | (int) pkt[1];
308 		s32 dy = signy | (int) pkt[2];
309 
310 		/* Update position based on velocity */
311 		priv->abs_x += dx * BYD_DT;
312 		priv->abs_y -= dy * BYD_DT;
313 
314 		priv->touch = true;
315 		break;
316 	}
317 	default:
318 		psmouse_warn(psmouse,
319 			     "Unrecognized Z: pkt = %02x %02x %02x %02x\n",
320 			     psmouse->packet[0], psmouse->packet[1],
321 			     psmouse->packet[2], psmouse->packet[3]);
322 		return PSMOUSE_BAD_DATA;
323 	}
324 
325 	priv->btn_left = pkt[0] & PS2_LEFT;
326 	priv->btn_right = pkt[0] & PS2_RIGHT;
327 
328 	byd_report_input(psmouse);
329 
330 	/* Reset time since last touch. */
331 	if (priv->touch) {
332 		priv->last_touch_time = jiffies;
333 		mod_timer(&priv->timer, jiffies + BYD_TOUCH_TIMEOUT);
334 	}
335 
336 	return PSMOUSE_FULL_PACKET;
337 }
338 
byd_reset_touchpad(struct psmouse * psmouse)339 static int byd_reset_touchpad(struct psmouse *psmouse)
340 {
341 	struct ps2dev *ps2dev = &psmouse->ps2dev;
342 	u8 param[4];
343 	size_t i;
344 
345 	static const struct {
346 		u16 command;
347 		u8 arg;
348 	} seq[] = {
349 		/*
350 		 * Intellimouse initialization sequence, to get 4-byte instead
351 		 * of 3-byte packets.
352 		 */
353 		{ PSMOUSE_CMD_SETRATE, 0xC8 },
354 		{ PSMOUSE_CMD_SETRATE, 0x64 },
355 		{ PSMOUSE_CMD_SETRATE, 0x50 },
356 		{ PSMOUSE_CMD_GETID, 0 },
357 		{ PSMOUSE_CMD_ENABLE, 0 },
358 		/*
359 		 * BYD-specific initialization, which enables absolute mode and
360 		 * (if desired), the touchpad's built-in gesture detection.
361 		 */
362 		{ 0x10E2, 0x00 },
363 		{ 0x10E0, 0x02 },
364 		/* The touchpad should reply with 4 seemingly-random bytes */
365 		{ 0x14E0, 0x01 },
366 		/* Pairs of parameters and values. */
367 		{ BYD_CMD_SET_HANDEDNESS, 0x01 },
368 		{ BYD_CMD_SET_PHYSICAL_BUTTONS, 0x04 },
369 		{ BYD_CMD_SET_TAP, 0x02 },
370 		{ BYD_CMD_SET_ONE_FINGER_SCROLL, 0x04 },
371 		{ BYD_CMD_SET_ONE_FINGER_SCROLL_FUNC, 0x04 },
372 		{ BYD_CMD_SET_EDGE_MOTION, 0x01 },
373 		{ BYD_CMD_SET_PALM_CHECK, 0x00 },
374 		{ BYD_CMD_SET_MULTITOUCH, 0x02 },
375 		{ BYD_CMD_SET_TWO_FINGER_SCROLL, 0x04 },
376 		{ BYD_CMD_SET_TWO_FINGER_SCROLL_FUNC, 0x04 },
377 		{ BYD_CMD_SET_LEFT_EDGE_REGION, 0x00 },
378 		{ BYD_CMD_SET_TOP_EDGE_REGION, 0x00 },
379 		{ BYD_CMD_SET_RIGHT_EDGE_REGION, 0x00 },
380 		{ BYD_CMD_SET_BOTTOM_EDGE_REGION, 0x00 },
381 		{ BYD_CMD_SET_ABSOLUTE_MODE, 0x02 },
382 		/* Finalize initialization. */
383 		{ 0x10E0, 0x00 },
384 		{ 0x10E2, 0x01 },
385 	};
386 
387 	for (i = 0; i < ARRAY_SIZE(seq); ++i) {
388 		memset(param, 0, sizeof(param));
389 		param[0] = seq[i].arg;
390 		if (ps2_command(ps2dev, param, seq[i].command))
391 			return -EIO;
392 	}
393 
394 	psmouse_set_state(psmouse, PSMOUSE_ACTIVATED);
395 	return 0;
396 }
397 
byd_reconnect(struct psmouse * psmouse)398 static int byd_reconnect(struct psmouse *psmouse)
399 {
400 	int retry = 0, error = 0;
401 
402 	psmouse_dbg(psmouse, "Reconnect\n");
403 	do {
404 		psmouse_reset(psmouse);
405 		if (retry)
406 			ssleep(1);
407 		error = byd_detect(psmouse, 0);
408 	} while (error && ++retry < 3);
409 
410 	if (error)
411 		return error;
412 
413 	psmouse_dbg(psmouse, "Reconnected after %d attempts\n", retry);
414 
415 	error = byd_reset_touchpad(psmouse);
416 	if (error) {
417 		psmouse_err(psmouse, "Unable to initialize device\n");
418 		return error;
419 	}
420 
421 	return 0;
422 }
423 
byd_disconnect(struct psmouse * psmouse)424 static void byd_disconnect(struct psmouse *psmouse)
425 {
426 	struct byd_data *priv = psmouse->private;
427 
428 	if (priv) {
429 		del_timer(&priv->timer);
430 		kfree(psmouse->private);
431 		psmouse->private = NULL;
432 	}
433 }
434 
byd_detect(struct psmouse * psmouse,bool set_properties)435 int byd_detect(struct psmouse *psmouse, bool set_properties)
436 {
437 	struct ps2dev *ps2dev = &psmouse->ps2dev;
438 	u8 param[4] = {0x03, 0x00, 0x00, 0x00};
439 
440 	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
441 		return -1;
442 	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
443 		return -1;
444 	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
445 		return -1;
446 	if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
447 		return -1;
448 	if (ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO))
449 		return -1;
450 
451 	if (param[1] != 0x03 || param[2] != 0x64)
452 		return -ENODEV;
453 
454 	psmouse_dbg(psmouse, "BYD touchpad detected\n");
455 
456 	if (set_properties) {
457 		psmouse->vendor = "BYD";
458 		psmouse->name = "TouchPad";
459 	}
460 
461 	return 0;
462 }
463 
byd_init(struct psmouse * psmouse)464 int byd_init(struct psmouse *psmouse)
465 {
466 	struct input_dev *dev = psmouse->dev;
467 	struct byd_data *priv;
468 
469 	if (psmouse_reset(psmouse))
470 		return -EIO;
471 
472 	if (byd_reset_touchpad(psmouse))
473 		return -EIO;
474 
475 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
476 	if (!priv)
477 		return -ENOMEM;
478 
479 	priv->psmouse = psmouse;
480 	timer_setup(&priv->timer, byd_clear_touch, 0);
481 
482 	psmouse->private = priv;
483 	psmouse->disconnect = byd_disconnect;
484 	psmouse->reconnect = byd_reconnect;
485 	psmouse->protocol_handler = byd_process_byte;
486 	psmouse->pktsize = 4;
487 	psmouse->resync_time = 0;
488 
489 	__set_bit(INPUT_PROP_POINTER, dev->propbit);
490 	/* Touchpad */
491 	__set_bit(BTN_TOUCH, dev->keybit);
492 	__set_bit(BTN_TOOL_FINGER, dev->keybit);
493 	/* Buttons */
494 	__set_bit(BTN_LEFT, dev->keybit);
495 	__set_bit(BTN_RIGHT, dev->keybit);
496 	__clear_bit(BTN_MIDDLE, dev->keybit);
497 
498 	/* Absolute position */
499 	__set_bit(EV_ABS, dev->evbit);
500 	input_set_abs_params(dev, ABS_X, 0, BYD_PAD_WIDTH, 0, 0);
501 	input_set_abs_params(dev, ABS_Y, 0, BYD_PAD_HEIGHT, 0, 0);
502 	input_abs_set_res(dev, ABS_X, BYD_PAD_RESOLUTION);
503 	input_abs_set_res(dev, ABS_Y, BYD_PAD_RESOLUTION);
504 	/* No relative support */
505 	__clear_bit(EV_REL, dev->evbit);
506 	__clear_bit(REL_X, dev->relbit);
507 	__clear_bit(REL_Y, dev->relbit);
508 
509 	return 0;
510 }
511