1 /*
2  * PS/2 mouse driver
3  *
4  * Copyright (c) 1999-2002 Vojtech Pavlik
5  * Copyright (c) 2003-2004 Dmitry Torokhov
6  */
7 
8 /*
9  * This program is free software; you can redistribute it and/or modify it
10  * under the terms of the GNU General Public License version 2 as published by
11  * the Free Software Foundation.
12  */
13 
14 #define pr_fmt(fmt)		KBUILD_MODNAME ": " fmt
15 #define psmouse_fmt(fmt)	fmt
16 
17 #include <linux/bitops.h>
18 #include <linux/delay.h>
19 #include <linux/module.h>
20 #include <linux/slab.h>
21 #include <linux/interrupt.h>
22 #include <linux/input.h>
23 #include <linux/serio.h>
24 #include <linux/init.h>
25 #include <linux/libps2.h>
26 #include <linux/mutex.h>
27 #include <linux/types.h>
28 
29 #include "psmouse.h"
30 #include "synaptics.h"
31 #include "logips2pp.h"
32 #include "alps.h"
33 #include "hgpk.h"
34 #include "lifebook.h"
35 #include "trackpoint.h"
36 #include "touchkit_ps2.h"
37 #include "elantech.h"
38 #include "sentelic.h"
39 #include "cypress_ps2.h"
40 #include "focaltech.h"
41 #include "vmmouse.h"
42 #include "byd.h"
43 
44 #define DRIVER_DESC	"PS/2 mouse driver"
45 
46 MODULE_AUTHOR("Vojtech Pavlik <vojtech@suse.cz>");
47 MODULE_DESCRIPTION(DRIVER_DESC);
48 MODULE_LICENSE("GPL");
49 
50 static unsigned int psmouse_max_proto = PSMOUSE_AUTO;
51 static int psmouse_set_maxproto(const char *val, const struct kernel_param *);
52 static int psmouse_get_maxproto(char *buffer, const struct kernel_param *kp);
53 static const struct kernel_param_ops param_ops_proto_abbrev = {
54 	.set = psmouse_set_maxproto,
55 	.get = psmouse_get_maxproto,
56 };
57 #define param_check_proto_abbrev(name, p)	__param_check(name, p, unsigned int)
58 module_param_named(proto, psmouse_max_proto, proto_abbrev, 0644);
59 MODULE_PARM_DESC(proto, "Highest protocol extension to probe (bare, imps, exps, any). Useful for KVM switches.");
60 
61 static unsigned int psmouse_resolution = 200;
62 module_param_named(resolution, psmouse_resolution, uint, 0644);
63 MODULE_PARM_DESC(resolution, "Resolution, in dpi.");
64 
65 static unsigned int psmouse_rate = 100;
66 module_param_named(rate, psmouse_rate, uint, 0644);
67 MODULE_PARM_DESC(rate, "Report rate, in reports per second.");
68 
69 static bool psmouse_smartscroll = true;
70 module_param_named(smartscroll, psmouse_smartscroll, bool, 0644);
71 MODULE_PARM_DESC(smartscroll, "Logitech Smartscroll autorepeat, 1 = enabled (default), 0 = disabled.");
72 
73 static bool psmouse_a4tech_2wheels;
74 module_param_named(a4tech_workaround, psmouse_a4tech_2wheels, bool, 0644);
75 MODULE_PARM_DESC(a4tech_workaround, "A4Tech second scroll wheel workaround, 1 = enabled, 0 = disabled (default).");
76 
77 static unsigned int psmouse_resetafter = 5;
78 module_param_named(resetafter, psmouse_resetafter, uint, 0644);
79 MODULE_PARM_DESC(resetafter, "Reset device after so many bad packets (0 = never).");
80 
81 static unsigned int psmouse_resync_time;
82 module_param_named(resync_time, psmouse_resync_time, uint, 0644);
83 MODULE_PARM_DESC(resync_time, "How long can mouse stay idle before forcing resync (in seconds, 0 = never).");
84 
85 PSMOUSE_DEFINE_ATTR(protocol, S_IWUSR | S_IRUGO,
86 			NULL,
87 			psmouse_attr_show_protocol, psmouse_attr_set_protocol);
88 PSMOUSE_DEFINE_ATTR(rate, S_IWUSR | S_IRUGO,
89 			(void *) offsetof(struct psmouse, rate),
90 			psmouse_show_int_attr, psmouse_attr_set_rate);
91 PSMOUSE_DEFINE_ATTR(resolution, S_IWUSR | S_IRUGO,
92 			(void *) offsetof(struct psmouse, resolution),
93 			psmouse_show_int_attr, psmouse_attr_set_resolution);
94 PSMOUSE_DEFINE_ATTR(resetafter, S_IWUSR | S_IRUGO,
95 			(void *) offsetof(struct psmouse, resetafter),
96 			psmouse_show_int_attr, psmouse_set_int_attr);
97 PSMOUSE_DEFINE_ATTR(resync_time, S_IWUSR | S_IRUGO,
98 			(void *) offsetof(struct psmouse, resync_time),
99 			psmouse_show_int_attr, psmouse_set_int_attr);
100 
101 static struct attribute *psmouse_attributes[] = {
102 	&psmouse_attr_protocol.dattr.attr,
103 	&psmouse_attr_rate.dattr.attr,
104 	&psmouse_attr_resolution.dattr.attr,
105 	&psmouse_attr_resetafter.dattr.attr,
106 	&psmouse_attr_resync_time.dattr.attr,
107 	NULL
108 };
109 
110 static const struct attribute_group psmouse_attribute_group = {
111 	.attrs	= psmouse_attributes,
112 };
113 
114 /*
115  * psmouse_mutex protects all operations changing state of mouse
116  * (connecting, disconnecting, changing rate or resolution via
117  * sysfs). We could use a per-device semaphore but since there
118  * rarely more than one PS/2 mouse connected and since semaphore
119  * is taken in "slow" paths it is not worth it.
120  */
121 static DEFINE_MUTEX(psmouse_mutex);
122 
123 static struct workqueue_struct *kpsmoused_wq;
124 
125 void psmouse_report_standard_buttons(struct input_dev *dev, u8 buttons)
126 {
127 	input_report_key(dev, BTN_LEFT,   buttons & BIT(0));
128 	input_report_key(dev, BTN_MIDDLE, buttons & BIT(2));
129 	input_report_key(dev, BTN_RIGHT,  buttons & BIT(1));
130 }
131 
132 void psmouse_report_standard_motion(struct input_dev *dev, u8 *packet)
133 {
134 	int x, y;
135 
136 	x = packet[1] ? packet[1] - ((packet[0] << 4) & 0x100) : 0;
137 	y = packet[2] ? packet[2] - ((packet[0] << 3) & 0x100) : 0;
138 
139 	input_report_rel(dev, REL_X, x);
140 	input_report_rel(dev, REL_Y, -y);
141 }
142 
143 void psmouse_report_standard_packet(struct input_dev *dev, u8 *packet)
144 {
145 	psmouse_report_standard_buttons(dev, packet[0]);
146 	psmouse_report_standard_motion(dev, packet);
147 }
148 
149 /*
150  * psmouse_process_byte() analyzes the PS/2 data stream and reports
151  * relevant events to the input module once full packet has arrived.
152  */
153 psmouse_ret_t psmouse_process_byte(struct psmouse *psmouse)
154 {
155 	struct input_dev *dev = psmouse->dev;
156 	u8 *packet = psmouse->packet;
157 	int wheel;
158 
159 	if (psmouse->pktcnt < psmouse->pktsize)
160 		return PSMOUSE_GOOD_DATA;
161 
162 	/* Full packet accumulated, process it */
163 
164 	switch (psmouse->protocol->type) {
165 	case PSMOUSE_IMPS:
166 		/* IntelliMouse has scroll wheel */
167 		input_report_rel(dev, REL_WHEEL, -(s8) packet[3]);
168 		break;
169 
170 	case PSMOUSE_IMEX:
171 		/* Scroll wheel and buttons on IntelliMouse Explorer */
172 		switch (packet[3] & 0xC0) {
173 		case 0x80: /* vertical scroll on IntelliMouse Explorer 4.0 */
174 			input_report_rel(dev, REL_WHEEL,
175 					 -sign_extend32(packet[3], 5));
176 			break;
177 		case 0x40: /* horizontal scroll on IntelliMouse Explorer 4.0 */
178 			input_report_rel(dev, REL_HWHEEL,
179 					 -sign_extend32(packet[3], 5));
180 			break;
181 		case 0x00:
182 		case 0xC0:
183 			wheel = sign_extend32(packet[3], 3);
184 
185 			/*
186 			 * Some A4Tech mice have two scroll wheels, with first
187 			 * one reporting +/-1 in the lower nibble, and second
188 			 * one reporting +/-2.
189 			 */
190 			if (psmouse_a4tech_2wheels && abs(wheel) > 1)
191 				input_report_rel(dev, REL_HWHEEL, wheel / 2);
192 			else
193 				input_report_rel(dev, REL_WHEEL, -wheel);
194 
195 			input_report_key(dev, BTN_SIDE,  BIT(4));
196 			input_report_key(dev, BTN_EXTRA, BIT(5));
197 			break;
198 		}
199 		break;
200 
201 	case PSMOUSE_GENPS:
202 		/* Report scroll buttons on NetMice */
203 		input_report_rel(dev, REL_WHEEL, -(s8) packet[3]);
204 
205 		/* Extra buttons on Genius NewNet 3D */
206 		input_report_key(dev, BTN_SIDE,  BIT(6));
207 		input_report_key(dev, BTN_EXTRA, BIT(7));
208 		break;
209 
210 	case PSMOUSE_THINKPS:
211 		/* Extra button on ThinkingMouse */
212 		input_report_key(dev, BTN_EXTRA, BIT(3));
213 
214 		/*
215 		 * Without this bit of weirdness moving up gives wildly
216 		 * high Y changes.
217 		 */
218 		packet[1] |= (packet[0] & 0x40) << 1;
219 		break;
220 
221 	case PSMOUSE_CORTRON:
222 		/*
223 		 * Cortron PS2 Trackball reports SIDE button in the
224 		 * 4th bit of the first byte.
225 		 */
226 		input_report_key(dev, BTN_SIDE, BIT(3));
227 		packet[0] |= BIT(3);
228 		break;
229 
230 	default:
231 		break;
232 	}
233 
234 	/* Generic PS/2 Mouse */
235 	packet[0] |= psmouse->extra_buttons;
236 	psmouse_report_standard_packet(dev, packet);
237 
238 	input_sync(dev);
239 
240 	return PSMOUSE_FULL_PACKET;
241 }
242 
243 void psmouse_queue_work(struct psmouse *psmouse, struct delayed_work *work,
244 		unsigned long delay)
245 {
246 	queue_delayed_work(kpsmoused_wq, work, delay);
247 }
248 
249 /*
250  * __psmouse_set_state() sets new psmouse state and resets all flags.
251  */
252 static inline void __psmouse_set_state(struct psmouse *psmouse, enum psmouse_state new_state)
253 {
254 	psmouse->state = new_state;
255 	psmouse->pktcnt = psmouse->out_of_sync_cnt = 0;
256 	psmouse->ps2dev.flags = 0;
257 	psmouse->last = jiffies;
258 }
259 
260 /*
261  * psmouse_set_state() sets new psmouse state and resets all flags and
262  * counters while holding serio lock so fighting with interrupt handler
263  * is not a concern.
264  */
265 void psmouse_set_state(struct psmouse *psmouse, enum psmouse_state new_state)
266 {
267 	serio_pause_rx(psmouse->ps2dev.serio);
268 	__psmouse_set_state(psmouse, new_state);
269 	serio_continue_rx(psmouse->ps2dev.serio);
270 }
271 
272 /*
273  * psmouse_handle_byte() processes one byte of the input data stream
274  * by calling corresponding protocol handler.
275  */
276 static int psmouse_handle_byte(struct psmouse *psmouse)
277 {
278 	psmouse_ret_t rc = psmouse->protocol_handler(psmouse);
279 
280 	switch (rc) {
281 	case PSMOUSE_BAD_DATA:
282 		if (psmouse->state == PSMOUSE_ACTIVATED) {
283 			psmouse_warn(psmouse,
284 				     "%s at %s lost sync at byte %d\n",
285 				     psmouse->name, psmouse->phys,
286 				     psmouse->pktcnt);
287 			if (++psmouse->out_of_sync_cnt == psmouse->resetafter) {
288 				__psmouse_set_state(psmouse, PSMOUSE_IGNORE);
289 				psmouse_notice(psmouse,
290 						"issuing reconnect request\n");
291 				serio_reconnect(psmouse->ps2dev.serio);
292 				return -EIO;
293 			}
294 		}
295 		psmouse->pktcnt = 0;
296 		break;
297 
298 	case PSMOUSE_FULL_PACKET:
299 		psmouse->pktcnt = 0;
300 		if (psmouse->out_of_sync_cnt) {
301 			psmouse->out_of_sync_cnt = 0;
302 			psmouse_notice(psmouse,
303 					"%s at %s - driver resynced.\n",
304 					psmouse->name, psmouse->phys);
305 		}
306 		break;
307 
308 	case PSMOUSE_GOOD_DATA:
309 		break;
310 	}
311 	return 0;
312 }
313 
314 static void psmouse_handle_oob_data(struct psmouse *psmouse, u8 data)
315 {
316 	switch (psmouse->oob_data_type) {
317 	case PSMOUSE_OOB_NONE:
318 		psmouse->oob_data_type = data;
319 		break;
320 
321 	case PSMOUSE_OOB_EXTRA_BTNS:
322 		psmouse_report_standard_buttons(psmouse->dev, data);
323 		input_sync(psmouse->dev);
324 
325 		psmouse->extra_buttons = data;
326 		psmouse->oob_data_type = PSMOUSE_OOB_NONE;
327 		break;
328 
329 	default:
330 		psmouse_warn(psmouse,
331 			     "unknown OOB_DATA type: 0x%02x\n",
332 			     psmouse->oob_data_type);
333 		psmouse->oob_data_type = PSMOUSE_OOB_NONE;
334 		break;
335 	}
336 }
337 
338 /*
339  * psmouse_interrupt() handles incoming characters, either passing them
340  * for normal processing or gathering them as command response.
341  */
342 static irqreturn_t psmouse_interrupt(struct serio *serio,
343 				     u8 data, unsigned int flags)
344 {
345 	struct psmouse *psmouse = serio_get_drvdata(serio);
346 
347 	if (psmouse->state == PSMOUSE_IGNORE)
348 		goto out;
349 
350 	if (unlikely((flags & SERIO_TIMEOUT) ||
351 		     ((flags & SERIO_PARITY) &&
352 		      !psmouse->protocol->ignore_parity))) {
353 
354 		if (psmouse->state == PSMOUSE_ACTIVATED)
355 			psmouse_warn(psmouse,
356 				     "bad data from KBC -%s%s\n",
357 				     flags & SERIO_TIMEOUT ? " timeout" : "",
358 				     flags & SERIO_PARITY ? " bad parity" : "");
359 		ps2_cmd_aborted(&psmouse->ps2dev);
360 		goto out;
361 	}
362 
363 	if (flags & SERIO_OOB_DATA) {
364 		psmouse_handle_oob_data(psmouse, data);
365 		goto out;
366 	}
367 
368 	if (unlikely(psmouse->ps2dev.flags & PS2_FLAG_ACK))
369 		if  (ps2_handle_ack(&psmouse->ps2dev, data))
370 			goto out;
371 
372 	if (unlikely(psmouse->ps2dev.flags & PS2_FLAG_CMD))
373 		if  (ps2_handle_response(&psmouse->ps2dev, data))
374 			goto out;
375 
376 	if (psmouse->state <= PSMOUSE_RESYNCING)
377 		goto out;
378 
379 	if (psmouse->state == PSMOUSE_ACTIVATED &&
380 	    psmouse->pktcnt && time_after(jiffies, psmouse->last + HZ/2)) {
381 		psmouse_info(psmouse, "%s at %s lost synchronization, throwing %d bytes away.\n",
382 			     psmouse->name, psmouse->phys, psmouse->pktcnt);
383 		psmouse->badbyte = psmouse->packet[0];
384 		__psmouse_set_state(psmouse, PSMOUSE_RESYNCING);
385 		psmouse_queue_work(psmouse, &psmouse->resync_work, 0);
386 		goto out;
387 	}
388 
389 	psmouse->packet[psmouse->pktcnt++] = data;
390 
391 	/* Check if this is a new device announcement (0xAA 0x00) */
392 	if (unlikely(psmouse->packet[0] == PSMOUSE_RET_BAT && psmouse->pktcnt <= 2)) {
393 		if (psmouse->pktcnt == 1) {
394 			psmouse->last = jiffies;
395 			goto out;
396 		}
397 
398 		if (psmouse->packet[1] == PSMOUSE_RET_ID ||
399 		    (psmouse->protocol->type == PSMOUSE_HGPK &&
400 		     psmouse->packet[1] == PSMOUSE_RET_BAT)) {
401 			__psmouse_set_state(psmouse, PSMOUSE_IGNORE);
402 			serio_reconnect(serio);
403 			goto out;
404 		}
405 
406 		/* Not a new device, try processing first byte normally */
407 		psmouse->pktcnt = 1;
408 		if (psmouse_handle_byte(psmouse))
409 			goto out;
410 
411 		psmouse->packet[psmouse->pktcnt++] = data;
412 	}
413 
414 	/*
415 	 * See if we need to force resync because mouse was idle for
416 	 * too long.
417 	 */
418 	if (psmouse->state == PSMOUSE_ACTIVATED &&
419 	    psmouse->pktcnt == 1 && psmouse->resync_time &&
420 	    time_after(jiffies, psmouse->last + psmouse->resync_time * HZ)) {
421 		psmouse->badbyte = psmouse->packet[0];
422 		__psmouse_set_state(psmouse, PSMOUSE_RESYNCING);
423 		psmouse_queue_work(psmouse, &psmouse->resync_work, 0);
424 		goto out;
425 	}
426 
427 	psmouse->last = jiffies;
428 	psmouse_handle_byte(psmouse);
429 
430  out:
431 	return IRQ_HANDLED;
432 }
433 
434 /*
435  * psmouse_reset() resets the mouse into power-on state.
436  */
437 int psmouse_reset(struct psmouse *psmouse)
438 {
439 	u8 param[2];
440 	int error;
441 
442 	error = ps2_command(&psmouse->ps2dev, param, PSMOUSE_CMD_RESET_BAT);
443 	if (error)
444 		return error;
445 
446 	if (param[0] != PSMOUSE_RET_BAT && param[1] != PSMOUSE_RET_ID)
447 		return -EIO;
448 
449 	return 0;
450 }
451 
452 /*
453  * Here we set the mouse resolution.
454  */
455 void psmouse_set_resolution(struct psmouse *psmouse, unsigned int resolution)
456 {
457 	static const u8 params[] = { 0, 1, 2, 2, 3 };
458 	u8 p;
459 
460 	if (resolution == 0 || resolution > 200)
461 		resolution = 200;
462 
463 	p = params[resolution / 50];
464 	ps2_command(&psmouse->ps2dev, &p, PSMOUSE_CMD_SETRES);
465 	psmouse->resolution = 25 << p;
466 }
467 
468 /*
469  * Here we set the mouse report rate.
470  */
471 static void psmouse_set_rate(struct psmouse *psmouse, unsigned int rate)
472 {
473 	static const u8 rates[] = { 200, 100, 80, 60, 40, 20, 10, 0 };
474 	u8 r;
475 	int i = 0;
476 
477 	while (rates[i] > rate)
478 		i++;
479 	r = rates[i];
480 	ps2_command(&psmouse->ps2dev, &r, PSMOUSE_CMD_SETRATE);
481 	psmouse->rate = r;
482 }
483 
484 /*
485  * Here we set the mouse scaling.
486  */
487 static void psmouse_set_scale(struct psmouse *psmouse, enum psmouse_scale scale)
488 {
489 	ps2_command(&psmouse->ps2dev, NULL,
490 		    scale == PSMOUSE_SCALE21 ? PSMOUSE_CMD_SETSCALE21 :
491 					       PSMOUSE_CMD_SETSCALE11);
492 }
493 
494 /*
495  * psmouse_poll() - default poll handler. Everyone except for ALPS uses it.
496  */
497 static int psmouse_poll(struct psmouse *psmouse)
498 {
499 	return ps2_command(&psmouse->ps2dev, psmouse->packet,
500 			   PSMOUSE_CMD_POLL | (psmouse->pktsize << 8));
501 }
502 
503 static bool psmouse_check_pnp_id(const char *id, const char * const ids[])
504 {
505 	int i;
506 
507 	for (i = 0; ids[i]; i++)
508 		if (!strcasecmp(id, ids[i]))
509 			return true;
510 
511 	return false;
512 }
513 
514 /*
515  * psmouse_matches_pnp_id - check if psmouse matches one of the passed in ids.
516  */
517 bool psmouse_matches_pnp_id(struct psmouse *psmouse, const char * const ids[])
518 {
519 	struct serio *serio = psmouse->ps2dev.serio;
520 	char *p, *fw_id_copy, *save_ptr;
521 	bool found = false;
522 
523 	if (strncmp(serio->firmware_id, "PNP: ", 5))
524 		return false;
525 
526 	fw_id_copy = kstrndup(&serio->firmware_id[5],
527 			      sizeof(serio->firmware_id) - 5,
528 			      GFP_KERNEL);
529 	if (!fw_id_copy)
530 		return false;
531 
532 	save_ptr = fw_id_copy;
533 	while ((p = strsep(&fw_id_copy, " ")) != NULL) {
534 		if (psmouse_check_pnp_id(p, ids)) {
535 			found = true;
536 			break;
537 		}
538 	}
539 
540 	kfree(save_ptr);
541 	return found;
542 }
543 
544 /*
545  * Genius NetMouse magic init.
546  */
547 static int genius_detect(struct psmouse *psmouse, bool set_properties)
548 {
549 	struct ps2dev *ps2dev = &psmouse->ps2dev;
550 	u8 param[4];
551 
552 	param[0] = 3;
553 	ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES);
554 	ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11);
555 	ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11);
556 	ps2_command(ps2dev,  NULL, PSMOUSE_CMD_SETSCALE11);
557 	ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO);
558 
559 	if (param[0] != 0x00 || param[1] != 0x33 || param[2] != 0x55)
560 		return -ENODEV;
561 
562 	if (set_properties) {
563 		__set_bit(BTN_MIDDLE, psmouse->dev->keybit);
564 		__set_bit(BTN_EXTRA, psmouse->dev->keybit);
565 		__set_bit(BTN_SIDE, psmouse->dev->keybit);
566 		__set_bit(REL_WHEEL, psmouse->dev->relbit);
567 
568 		psmouse->vendor = "Genius";
569 		psmouse->name = "Mouse";
570 		psmouse->pktsize = 4;
571 	}
572 
573 	return 0;
574 }
575 
576 /*
577  * IntelliMouse magic init.
578  */
579 static int intellimouse_detect(struct psmouse *psmouse, bool set_properties)
580 {
581 	struct ps2dev *ps2dev = &psmouse->ps2dev;
582 	u8 param[2];
583 
584 	param[0] = 200;
585 	ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
586 	param[0] = 100;
587 	ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
588 	param[0] =  80;
589 	ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
590 	ps2_command(ps2dev, param, PSMOUSE_CMD_GETID);
591 
592 	if (param[0] != 3)
593 		return -ENODEV;
594 
595 	if (set_properties) {
596 		__set_bit(BTN_MIDDLE, psmouse->dev->keybit);
597 		__set_bit(REL_WHEEL, psmouse->dev->relbit);
598 
599 		if (!psmouse->vendor)
600 			psmouse->vendor = "Generic";
601 		if (!psmouse->name)
602 			psmouse->name = "Wheel Mouse";
603 		psmouse->pktsize = 4;
604 	}
605 
606 	return 0;
607 }
608 
609 /*
610  * Try IntelliMouse/Explorer magic init.
611  */
612 static int im_explorer_detect(struct psmouse *psmouse, bool set_properties)
613 {
614 	struct ps2dev *ps2dev = &psmouse->ps2dev;
615 	u8 param[2];
616 
617 	intellimouse_detect(psmouse, 0);
618 
619 	param[0] = 200;
620 	ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
621 	param[0] = 200;
622 	ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
623 	param[0] =  80;
624 	ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
625 	ps2_command(ps2dev, param, PSMOUSE_CMD_GETID);
626 
627 	if (param[0] != 4)
628 		return -ENODEV;
629 
630 	/* Magic to enable horizontal scrolling on IntelliMouse 4.0 */
631 	param[0] = 200;
632 	ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
633 	param[0] =  80;
634 	ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
635 	param[0] =  40;
636 	ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
637 
638 	if (set_properties) {
639 		__set_bit(BTN_MIDDLE, psmouse->dev->keybit);
640 		__set_bit(REL_WHEEL, psmouse->dev->relbit);
641 		__set_bit(REL_HWHEEL, psmouse->dev->relbit);
642 		__set_bit(BTN_SIDE, psmouse->dev->keybit);
643 		__set_bit(BTN_EXTRA, psmouse->dev->keybit);
644 
645 		if (!psmouse->vendor)
646 			psmouse->vendor = "Generic";
647 		if (!psmouse->name)
648 			psmouse->name = "Explorer Mouse";
649 		psmouse->pktsize = 4;
650 	}
651 
652 	return 0;
653 }
654 
655 /*
656  * Kensington ThinkingMouse / ExpertMouse magic init.
657  */
658 static int thinking_detect(struct psmouse *psmouse, bool set_properties)
659 {
660 	struct ps2dev *ps2dev = &psmouse->ps2dev;
661 	u8 param[2];
662 	static const u8 seq[] = { 20, 60, 40, 20, 20, 60, 40, 20, 20 };
663 	int i;
664 
665 	param[0] = 10;
666 	ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
667 	param[0] = 0;
668 	ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES);
669 	for (i = 0; i < ARRAY_SIZE(seq); i++) {
670 		param[0] = seq[i];
671 		ps2_command(ps2dev, param, PSMOUSE_CMD_SETRATE);
672 	}
673 	ps2_command(ps2dev, param, PSMOUSE_CMD_GETID);
674 
675 	if (param[0] != 2)
676 		return -ENODEV;
677 
678 	if (set_properties) {
679 		__set_bit(BTN_MIDDLE, psmouse->dev->keybit);
680 		__set_bit(BTN_EXTRA, psmouse->dev->keybit);
681 
682 		psmouse->vendor = "Kensington";
683 		psmouse->name = "ThinkingMouse";
684 	}
685 
686 	return 0;
687 }
688 
689 /*
690  * Bare PS/2 protocol "detection". Always succeeds.
691  */
692 static int ps2bare_detect(struct psmouse *psmouse, bool set_properties)
693 {
694 	if (set_properties) {
695 		if (!psmouse->vendor)
696 			psmouse->vendor = "Generic";
697 		if (!psmouse->name)
698 			psmouse->name = "Mouse";
699 
700 		/*
701 		 * We have no way of figuring true number of buttons so let's
702 		 * assume that the device has 3.
703 		 */
704 		input_set_capability(psmouse->dev, EV_KEY, BTN_MIDDLE);
705 	}
706 
707 	return 0;
708 }
709 
710 /*
711  * Cortron PS/2 protocol detection. There's no special way to detect it, so it
712  * must be forced by sysfs protocol writing.
713  */
714 static int cortron_detect(struct psmouse *psmouse, bool set_properties)
715 {
716 	if (set_properties) {
717 		psmouse->vendor = "Cortron";
718 		psmouse->name = "PS/2 Trackball";
719 
720 		__set_bit(BTN_MIDDLE, psmouse->dev->keybit);
721 		__set_bit(BTN_SIDE, psmouse->dev->keybit);
722 	}
723 
724 	return 0;
725 }
726 
727 static const struct psmouse_protocol psmouse_protocols[] = {
728 	{
729 		.type		= PSMOUSE_PS2,
730 		.name		= "PS/2",
731 		.alias		= "bare",
732 		.maxproto	= true,
733 		.ignore_parity	= true,
734 		.detect		= ps2bare_detect,
735 		.try_passthru	= true,
736 	},
737 #ifdef CONFIG_MOUSE_PS2_LOGIPS2PP
738 	{
739 		.type		= PSMOUSE_PS2PP,
740 		.name		= "PS2++",
741 		.alias		= "logitech",
742 		.detect		= ps2pp_detect,
743 	},
744 #endif
745 	{
746 		.type		= PSMOUSE_THINKPS,
747 		.name		= "ThinkPS/2",
748 		.alias		= "thinkps",
749 		.detect		= thinking_detect,
750 	},
751 #ifdef CONFIG_MOUSE_PS2_CYPRESS
752 	{
753 		.type		= PSMOUSE_CYPRESS,
754 		.name		= "CyPS/2",
755 		.alias		= "cypress",
756 		.detect		= cypress_detect,
757 		.init		= cypress_init,
758 	},
759 #endif
760 	{
761 		.type		= PSMOUSE_GENPS,
762 		.name		= "GenPS/2",
763 		.alias		= "genius",
764 		.detect		= genius_detect,
765 	},
766 	{
767 		.type		= PSMOUSE_IMPS,
768 		.name		= "ImPS/2",
769 		.alias		= "imps",
770 		.maxproto	= true,
771 		.ignore_parity	= true,
772 		.detect		= intellimouse_detect,
773 		.try_passthru	= true,
774 	},
775 	{
776 		.type		= PSMOUSE_IMEX,
777 		.name		= "ImExPS/2",
778 		.alias		= "exps",
779 		.maxproto	= true,
780 		.ignore_parity	= true,
781 		.detect		= im_explorer_detect,
782 		.try_passthru	= true,
783 	},
784 #ifdef CONFIG_MOUSE_PS2_SYNAPTICS
785 	{
786 		.type		= PSMOUSE_SYNAPTICS,
787 		.name		= "SynPS/2",
788 		.alias		= "synaptics",
789 		.detect		= synaptics_detect,
790 		.init		= synaptics_init_absolute,
791 	},
792 	{
793 		.type		= PSMOUSE_SYNAPTICS_RELATIVE,
794 		.name		= "SynRelPS/2",
795 		.alias		= "synaptics-relative",
796 		.detect		= synaptics_detect,
797 		.init		= synaptics_init_relative,
798 	},
799 #endif
800 #ifdef CONFIG_MOUSE_PS2_SYNAPTICS_SMBUS
801 	{
802 		.type		= PSMOUSE_SYNAPTICS_SMBUS,
803 		.name		= "SynSMBus",
804 		.alias		= "synaptics-smbus",
805 		.detect		= synaptics_detect,
806 		.init		= synaptics_init_smbus,
807 		.smbus_companion = true,
808 	},
809 #endif
810 #ifdef CONFIG_MOUSE_PS2_ALPS
811 	{
812 		.type		= PSMOUSE_ALPS,
813 		.name		= "AlpsPS/2",
814 		.alias		= "alps",
815 		.detect		= alps_detect,
816 		.init		= alps_init,
817 	},
818 #endif
819 #ifdef CONFIG_MOUSE_PS2_LIFEBOOK
820 	{
821 		.type		= PSMOUSE_LIFEBOOK,
822 		.name		= "LBPS/2",
823 		.alias		= "lifebook",
824 		.detect		= lifebook_detect,
825 		.init		= lifebook_init,
826 	},
827 #endif
828 #ifdef CONFIG_MOUSE_PS2_TRACKPOINT
829 	{
830 		.type		= PSMOUSE_TRACKPOINT,
831 		.name		= "TPPS/2",
832 		.alias		= "trackpoint",
833 		.detect		= trackpoint_detect,
834 		.try_passthru	= true,
835 	},
836 #endif
837 #ifdef CONFIG_MOUSE_PS2_TOUCHKIT
838 	{
839 		.type		= PSMOUSE_TOUCHKIT_PS2,
840 		.name		= "touchkitPS/2",
841 		.alias		= "touchkit",
842 		.detect		= touchkit_ps2_detect,
843 	},
844 #endif
845 #ifdef CONFIG_MOUSE_PS2_OLPC
846 	{
847 		.type		= PSMOUSE_HGPK,
848 		.name		= "OLPC HGPK",
849 		.alias		= "hgpk",
850 		.detect		= hgpk_detect,
851 	},
852 #endif
853 #ifdef CONFIG_MOUSE_PS2_ELANTECH
854 	{
855 		.type		= PSMOUSE_ELANTECH,
856 		.name		= "ETPS/2",
857 		.alias		= "elantech",
858 		.detect		= elantech_detect,
859 		.init		= elantech_init,
860 	},
861 #endif
862 #ifdef CONFIG_MOUSE_PS2_SENTELIC
863 	{
864 		.type		= PSMOUSE_FSP,
865 		.name		= "FSPPS/2",
866 		.alias		= "fsp",
867 		.detect		= fsp_detect,
868 		.init		= fsp_init,
869 	},
870 #endif
871 	{
872 		.type		= PSMOUSE_CORTRON,
873 		.name		= "CortronPS/2",
874 		.alias		= "cortps",
875 		.detect		= cortron_detect,
876 	},
877 #ifdef CONFIG_MOUSE_PS2_FOCALTECH
878 	{
879 		.type		= PSMOUSE_FOCALTECH,
880 		.name		= "FocalTechPS/2",
881 		.alias		= "focaltech",
882 		.detect		= focaltech_detect,
883 		.init		= focaltech_init,
884 	},
885 #endif
886 #ifdef CONFIG_MOUSE_PS2_VMMOUSE
887 	{
888 		.type		= PSMOUSE_VMMOUSE,
889 		.name		= VMMOUSE_PSNAME,
890 		.alias		= "vmmouse",
891 		.detect		= vmmouse_detect,
892 		.init		= vmmouse_init,
893 	},
894 #endif
895 #ifdef CONFIG_MOUSE_PS2_BYD
896 	{
897 		.type		= PSMOUSE_BYD,
898 		.name		= "BYDPS/2",
899 		.alias		= "byd",
900 		.detect		= byd_detect,
901 		.init		= byd_init,
902 	},
903 #endif
904 	{
905 		.type		= PSMOUSE_AUTO,
906 		.name		= "auto",
907 		.alias		= "any",
908 		.maxproto	= true,
909 	},
910 };
911 
912 static const struct psmouse_protocol *__psmouse_protocol_by_type(enum psmouse_type type)
913 {
914 	int i;
915 
916 	for (i = 0; i < ARRAY_SIZE(psmouse_protocols); i++)
917 		if (psmouse_protocols[i].type == type)
918 			return &psmouse_protocols[i];
919 
920 	return NULL;
921 }
922 
923 static const struct psmouse_protocol *psmouse_protocol_by_type(enum psmouse_type type)
924 {
925 	const struct psmouse_protocol *proto;
926 
927 	proto = __psmouse_protocol_by_type(type);
928 	if (proto)
929 		return proto;
930 
931 	WARN_ON(1);
932 	return &psmouse_protocols[0];
933 }
934 
935 static const struct psmouse_protocol *psmouse_protocol_by_name(const char *name, size_t len)
936 {
937 	const struct psmouse_protocol *p;
938 	int i;
939 
940 	for (i = 0; i < ARRAY_SIZE(psmouse_protocols); i++) {
941 		p = &psmouse_protocols[i];
942 
943 		if ((strlen(p->name) == len && !strncmp(p->name, name, len)) ||
944 		    (strlen(p->alias) == len && !strncmp(p->alias, name, len)))
945 			return &psmouse_protocols[i];
946 	}
947 
948 	return NULL;
949 }
950 
951 /*
952  * Apply default settings to the psmouse structure. Most of them will
953  * be overridden by individual protocol initialization routines.
954  */
955 static void psmouse_apply_defaults(struct psmouse *psmouse)
956 {
957 	struct input_dev *input_dev = psmouse->dev;
958 
959 	bitmap_zero(input_dev->evbit, EV_CNT);
960 	bitmap_zero(input_dev->keybit, KEY_CNT);
961 	bitmap_zero(input_dev->relbit, REL_CNT);
962 	bitmap_zero(input_dev->absbit, ABS_CNT);
963 	bitmap_zero(input_dev->mscbit, MSC_CNT);
964 
965 	input_set_capability(input_dev, EV_KEY, BTN_LEFT);
966 	input_set_capability(input_dev, EV_KEY, BTN_RIGHT);
967 
968 	input_set_capability(input_dev, EV_REL, REL_X);
969 	input_set_capability(input_dev, EV_REL, REL_Y);
970 
971 	__set_bit(INPUT_PROP_POINTER, input_dev->propbit);
972 
973 	psmouse->protocol = &psmouse_protocols[0];
974 
975 	psmouse->set_rate = psmouse_set_rate;
976 	psmouse->set_resolution = psmouse_set_resolution;
977 	psmouse->set_scale = psmouse_set_scale;
978 	psmouse->poll = psmouse_poll;
979 	psmouse->protocol_handler = psmouse_process_byte;
980 	psmouse->pktsize = 3;
981 	psmouse->reconnect = NULL;
982 	psmouse->fast_reconnect = NULL;
983 	psmouse->disconnect = NULL;
984 	psmouse->cleanup = NULL;
985 	psmouse->pt_activate = NULL;
986 	psmouse->pt_deactivate = NULL;
987 }
988 
989 static bool psmouse_do_detect(int (*detect)(struct psmouse *, bool),
990 			      struct psmouse *psmouse, bool allow_passthrough,
991 			      bool set_properties)
992 {
993 	if (psmouse->ps2dev.serio->id.type == SERIO_PS_PSTHRU &&
994 	    !allow_passthrough) {
995 		return false;
996 	}
997 
998 	if (set_properties)
999 		psmouse_apply_defaults(psmouse);
1000 
1001 	return detect(psmouse, set_properties) == 0;
1002 }
1003 
1004 static bool psmouse_try_protocol(struct psmouse *psmouse,
1005 				 enum psmouse_type type,
1006 				 unsigned int *max_proto,
1007 				 bool set_properties, bool init_allowed)
1008 {
1009 	const struct psmouse_protocol *proto;
1010 
1011 	proto = __psmouse_protocol_by_type(type);
1012 	if (!proto)
1013 		return false;
1014 
1015 	if (!psmouse_do_detect(proto->detect, psmouse, proto->try_passthru,
1016 			       set_properties))
1017 		return false;
1018 
1019 	if (set_properties && proto->init && init_allowed) {
1020 		if (proto->init(psmouse) != 0) {
1021 			/*
1022 			 * We detected device, but init failed. Adjust
1023 			 * max_proto so we only try standard protocols.
1024 			 */
1025 			if (*max_proto > PSMOUSE_IMEX)
1026 				*max_proto = PSMOUSE_IMEX;
1027 
1028 			return false;
1029 		}
1030 	}
1031 
1032 	return true;
1033 }
1034 
1035 /*
1036  * psmouse_extensions() probes for any extensions to the basic PS/2 protocol
1037  * the mouse may have.
1038  */
1039 static int psmouse_extensions(struct psmouse *psmouse,
1040 			      unsigned int max_proto, bool set_properties)
1041 {
1042 	bool synaptics_hardware = false;
1043 	int ret;
1044 
1045 	/*
1046 	 * Always check for focaltech, this is safe as it uses pnp-id
1047 	 * matching.
1048 	 */
1049 	if (psmouse_do_detect(focaltech_detect,
1050 			      psmouse, false, set_properties)) {
1051 		if (max_proto > PSMOUSE_IMEX &&
1052 		    IS_ENABLED(CONFIG_MOUSE_PS2_FOCALTECH) &&
1053 		    (!set_properties || focaltech_init(psmouse) == 0)) {
1054 			return PSMOUSE_FOCALTECH;
1055 		}
1056 		/*
1057 		 * Restrict psmouse_max_proto so that psmouse_initialize()
1058 		 * does not try to reset rate and resolution, because even
1059 		 * that upsets the device.
1060 		 * This also causes us to basically fall through to basic
1061 		 * protocol detection, where we fully reset the mouse,
1062 		 * and set it up as bare PS/2 protocol device.
1063 		 */
1064 		psmouse_max_proto = max_proto = PSMOUSE_PS2;
1065 	}
1066 
1067 	/*
1068 	 * We always check for LifeBook because it does not disturb mouse
1069 	 * (it only checks DMI information).
1070 	 */
1071 	if (psmouse_try_protocol(psmouse, PSMOUSE_LIFEBOOK, &max_proto,
1072 				 set_properties, max_proto > PSMOUSE_IMEX))
1073 		return PSMOUSE_LIFEBOOK;
1074 
1075 	if (psmouse_try_protocol(psmouse, PSMOUSE_VMMOUSE, &max_proto,
1076 				 set_properties, max_proto > PSMOUSE_IMEX))
1077 		return PSMOUSE_VMMOUSE;
1078 
1079 	/*
1080 	 * Try Kensington ThinkingMouse (we try first, because Synaptics
1081 	 * probe upsets the ThinkingMouse).
1082 	 */
1083 	if (max_proto > PSMOUSE_IMEX &&
1084 	    psmouse_try_protocol(psmouse, PSMOUSE_THINKPS, &max_proto,
1085 				 set_properties, true)) {
1086 		return PSMOUSE_THINKPS;
1087 	}
1088 
1089 	/*
1090 	 * Try Synaptics TouchPad. Note that probing is done even if
1091 	 * Synaptics protocol support is disabled in config - we need to
1092 	 * know if it is Synaptics so we can reset it properly after
1093 	 * probing for IntelliMouse.
1094 	 */
1095 	if (max_proto > PSMOUSE_PS2 &&
1096 	    psmouse_do_detect(synaptics_detect,
1097 			      psmouse, false, set_properties)) {
1098 		synaptics_hardware = true;
1099 
1100 		if (max_proto > PSMOUSE_IMEX) {
1101 			/*
1102 			 * Try activating protocol, but check if support is
1103 			 * enabled first, since we try detecting Synaptics
1104 			 * even when protocol is disabled.
1105 			 */
1106 			if (IS_ENABLED(CONFIG_MOUSE_PS2_SYNAPTICS) ||
1107 			    IS_ENABLED(CONFIG_MOUSE_PS2_SYNAPTICS_SMBUS)) {
1108 				if (!set_properties)
1109 					return PSMOUSE_SYNAPTICS;
1110 
1111 				ret = synaptics_init(psmouse);
1112 				if (ret >= 0)
1113 					return ret;
1114 			}
1115 
1116 			/*
1117 			 * Some Synaptics touchpads can emulate extended
1118 			 * protocols (like IMPS/2).  Unfortunately
1119 			 * Logitech/Genius probes confuse some firmware
1120 			 * versions so we'll have to skip them.
1121 			 */
1122 			max_proto = PSMOUSE_IMEX;
1123 		}
1124 
1125 		/*
1126 		 * Make sure that touchpad is in relative mode, gestures
1127 		 * (taps) are enabled.
1128 		 */
1129 		synaptics_reset(psmouse);
1130 	}
1131 
1132 	/*
1133 	 * Try Cypress Trackpad. We must try it before Finger Sensing Pad
1134 	 * because Finger Sensing Pad probe upsets some modules of Cypress
1135 	 * Trackpads.
1136 	 */
1137 	if (max_proto > PSMOUSE_IMEX &&
1138 	    psmouse_try_protocol(psmouse, PSMOUSE_CYPRESS, &max_proto,
1139 				 set_properties, true)) {
1140 		return PSMOUSE_CYPRESS;
1141 	}
1142 
1143 	/* Try ALPS TouchPad */
1144 	if (max_proto > PSMOUSE_IMEX) {
1145 		ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_RESET_DIS);
1146 		if (psmouse_try_protocol(psmouse, PSMOUSE_ALPS,
1147 					 &max_proto, set_properties, true))
1148 			return PSMOUSE_ALPS;
1149 	}
1150 
1151 	/* Try OLPC HGPK touchpad */
1152 	if (max_proto > PSMOUSE_IMEX &&
1153 	    psmouse_try_protocol(psmouse, PSMOUSE_HGPK, &max_proto,
1154 				 set_properties, true)) {
1155 		return PSMOUSE_HGPK;
1156 	}
1157 
1158 	/* Try Elantech touchpad */
1159 	if (max_proto > PSMOUSE_IMEX &&
1160 	    psmouse_try_protocol(psmouse, PSMOUSE_ELANTECH,
1161 				 &max_proto, set_properties, true)) {
1162 		return PSMOUSE_ELANTECH;
1163 	}
1164 
1165 	if (max_proto > PSMOUSE_IMEX) {
1166 		if (psmouse_try_protocol(psmouse, PSMOUSE_GENPS,
1167 					 &max_proto, set_properties, true))
1168 			return PSMOUSE_GENPS;
1169 
1170 		if (psmouse_try_protocol(psmouse, PSMOUSE_PS2PP,
1171 					 &max_proto, set_properties, true))
1172 			return PSMOUSE_PS2PP;
1173 
1174 		if (psmouse_try_protocol(psmouse, PSMOUSE_TRACKPOINT,
1175 					 &max_proto, set_properties, true))
1176 			return PSMOUSE_TRACKPOINT;
1177 
1178 		if (psmouse_try_protocol(psmouse, PSMOUSE_TOUCHKIT_PS2,
1179 					 &max_proto, set_properties, true))
1180 			return PSMOUSE_TOUCHKIT_PS2;
1181 	}
1182 
1183 	/*
1184 	 * Try Finger Sensing Pad. We do it here because its probe upsets
1185 	 * Trackpoint devices (causing TP_READ_ID command to time out).
1186 	 */
1187 	if (max_proto > PSMOUSE_IMEX &&
1188 	    psmouse_try_protocol(psmouse, PSMOUSE_FSP,
1189 				 &max_proto, set_properties, true)) {
1190 		return PSMOUSE_FSP;
1191 	}
1192 
1193 	/*
1194 	 * Reset to defaults in case the device got confused by extended
1195 	 * protocol probes. Note that we follow up with full reset because
1196 	 * some mice put themselves to sleep when they see PSMOUSE_RESET_DIS.
1197 	 */
1198 	ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_RESET_DIS);
1199 	psmouse_reset(psmouse);
1200 
1201 	if (max_proto >= PSMOUSE_IMEX &&
1202 	    psmouse_try_protocol(psmouse, PSMOUSE_IMEX,
1203 				 &max_proto, set_properties, true)) {
1204 		return PSMOUSE_IMEX;
1205 	}
1206 
1207 	if (max_proto >= PSMOUSE_IMPS &&
1208 	    psmouse_try_protocol(psmouse, PSMOUSE_IMPS,
1209 				 &max_proto, set_properties, true)) {
1210 		return PSMOUSE_IMPS;
1211 	}
1212 
1213 	/*
1214 	 * Okay, all failed, we have a standard mouse here. The number of
1215 	 * the buttons is still a question, though. We assume 3.
1216 	 */
1217 	psmouse_try_protocol(psmouse, PSMOUSE_PS2,
1218 			     &max_proto, set_properties, true);
1219 
1220 	if (synaptics_hardware) {
1221 		/*
1222 		 * We detected Synaptics hardware but it did not respond to
1223 		 * IMPS/2 probes.  We need to reset the touchpad because if
1224 		 * there is a track point on the pass through port it could
1225 		 * get disabled while probing for protocol extensions.
1226 		 */
1227 		psmouse_reset(psmouse);
1228 	}
1229 
1230 	return PSMOUSE_PS2;
1231 }
1232 
1233 /*
1234  * psmouse_probe() probes for a PS/2 mouse.
1235  */
1236 static int psmouse_probe(struct psmouse *psmouse)
1237 {
1238 	struct ps2dev *ps2dev = &psmouse->ps2dev;
1239 	u8 param[2];
1240 	int error;
1241 
1242 	/*
1243 	 * First, we check if it's a mouse. It should send 0x00 or 0x03 in
1244 	 * case of an IntelliMouse in 4-byte mode or 0x04 for IM Explorer.
1245 	 * Sunrex K8561 IR Keyboard/Mouse reports 0xff on second and
1246 	 * subsequent ID queries, probably due to a firmware bug.
1247 	 */
1248 	param[0] = 0xa5;
1249 	error = ps2_command(ps2dev, param, PSMOUSE_CMD_GETID);
1250 	if (error)
1251 		return error;
1252 
1253 	if (param[0] != 0x00 && param[0] != 0x03 &&
1254 	    param[0] != 0x04 && param[0] != 0xff)
1255 		return -ENODEV;
1256 
1257 	/*
1258 	 * Then we reset and disable the mouse so that it doesn't generate
1259 	 * events.
1260 	 */
1261 	error = ps2_command(ps2dev, NULL, PSMOUSE_CMD_RESET_DIS);
1262 	if (error)
1263 		psmouse_warn(psmouse, "Failed to reset mouse on %s: %d\n",
1264 			     ps2dev->serio->phys, error);
1265 
1266 	return 0;
1267 }
1268 
1269 /*
1270  * psmouse_initialize() initializes the mouse to a sane state.
1271  */
1272 static void psmouse_initialize(struct psmouse *psmouse)
1273 {
1274 	/*
1275 	 * We set the mouse report rate, resolution and scaling.
1276 	 */
1277 	if (psmouse_max_proto != PSMOUSE_PS2) {
1278 		psmouse->set_rate(psmouse, psmouse->rate);
1279 		psmouse->set_resolution(psmouse, psmouse->resolution);
1280 		psmouse->set_scale(psmouse, PSMOUSE_SCALE11);
1281 	}
1282 }
1283 
1284 /*
1285  * psmouse_activate() enables the mouse so that we get motion reports from it.
1286  */
1287 int psmouse_activate(struct psmouse *psmouse)
1288 {
1289 	if (ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_ENABLE)) {
1290 		psmouse_warn(psmouse, "Failed to enable mouse on %s\n",
1291 			     psmouse->ps2dev.serio->phys);
1292 		return -1;
1293 	}
1294 
1295 	psmouse_set_state(psmouse, PSMOUSE_ACTIVATED);
1296 	return 0;
1297 }
1298 
1299 /*
1300  * psmouse_deactivate() puts the mouse into poll mode so that we don't get
1301  * motion reports from it unless we explicitly request it.
1302  */
1303 int psmouse_deactivate(struct psmouse *psmouse)
1304 {
1305 	int error;
1306 
1307 	error = ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_DISABLE);
1308 	if (error) {
1309 		psmouse_warn(psmouse, "Failed to deactivate mouse on %s: %d\n",
1310 			     psmouse->ps2dev.serio->phys, error);
1311 		return error;
1312 	}
1313 
1314 	psmouse_set_state(psmouse, PSMOUSE_CMD_MODE);
1315 	return 0;
1316 }
1317 
1318 /*
1319  * psmouse_resync() attempts to re-validate current protocol.
1320  */
1321 static void psmouse_resync(struct work_struct *work)
1322 {
1323 	struct psmouse *parent = NULL, *psmouse =
1324 		container_of(work, struct psmouse, resync_work.work);
1325 	struct serio *serio = psmouse->ps2dev.serio;
1326 	psmouse_ret_t rc = PSMOUSE_GOOD_DATA;
1327 	bool failed = false, enabled = false;
1328 	int i;
1329 
1330 	mutex_lock(&psmouse_mutex);
1331 
1332 	if (psmouse->state != PSMOUSE_RESYNCING)
1333 		goto out;
1334 
1335 	if (serio->parent && serio->id.type == SERIO_PS_PSTHRU) {
1336 		parent = serio_get_drvdata(serio->parent);
1337 		psmouse_deactivate(parent);
1338 	}
1339 
1340 	/*
1341 	 * Some mice don't ACK commands sent while they are in the middle of
1342 	 * transmitting motion packet. To avoid delay we use ps2_sendbyte()
1343 	 * instead of ps2_command() which would wait for 200ms for an ACK
1344 	 * that may never come.
1345 	 * As an additional quirk ALPS touchpads may not only forget to ACK
1346 	 * disable command but will stop reporting taps, so if we see that
1347 	 * mouse at least once ACKs disable we will do full reconnect if ACK
1348 	 * is missing.
1349 	 */
1350 	psmouse->num_resyncs++;
1351 
1352 	if (ps2_sendbyte(&psmouse->ps2dev, PSMOUSE_CMD_DISABLE, 20)) {
1353 		if (psmouse->num_resyncs < 3 || psmouse->acks_disable_command)
1354 			failed = true;
1355 	} else
1356 		psmouse->acks_disable_command = true;
1357 
1358 	/*
1359 	 * Poll the mouse. If it was reset the packet will be shorter than
1360 	 * psmouse->pktsize and ps2_command will fail. We do not expect and
1361 	 * do not handle scenario when mouse "upgrades" its protocol while
1362 	 * disconnected since it would require additional delay. If we ever
1363 	 * see a mouse that does it we'll adjust the code.
1364 	 */
1365 	if (!failed) {
1366 		if (psmouse->poll(psmouse))
1367 			failed = true;
1368 		else {
1369 			psmouse_set_state(psmouse, PSMOUSE_CMD_MODE);
1370 			for (i = 0; i < psmouse->pktsize; i++) {
1371 				psmouse->pktcnt++;
1372 				rc = psmouse->protocol_handler(psmouse);
1373 				if (rc != PSMOUSE_GOOD_DATA)
1374 					break;
1375 			}
1376 			if (rc != PSMOUSE_FULL_PACKET)
1377 				failed = true;
1378 			psmouse_set_state(psmouse, PSMOUSE_RESYNCING);
1379 		}
1380 	}
1381 
1382 	/*
1383 	 * Now try to enable mouse. We try to do that even if poll failed
1384 	 * and also repeat our attempts 5 times, otherwise we may be left
1385 	 * out with disabled mouse.
1386 	 */
1387 	for (i = 0; i < 5; i++) {
1388 		if (!ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_ENABLE)) {
1389 			enabled = true;
1390 			break;
1391 		}
1392 		msleep(200);
1393 	}
1394 
1395 	if (!enabled) {
1396 		psmouse_warn(psmouse, "failed to re-enable mouse on %s\n",
1397 			     psmouse->ps2dev.serio->phys);
1398 		failed = true;
1399 	}
1400 
1401 	if (failed) {
1402 		psmouse_set_state(psmouse, PSMOUSE_IGNORE);
1403 		psmouse_info(psmouse,
1404 			     "resync failed, issuing reconnect request\n");
1405 		serio_reconnect(serio);
1406 	} else
1407 		psmouse_set_state(psmouse, PSMOUSE_ACTIVATED);
1408 
1409 	if (parent)
1410 		psmouse_activate(parent);
1411  out:
1412 	mutex_unlock(&psmouse_mutex);
1413 }
1414 
1415 /*
1416  * psmouse_cleanup() resets the mouse into power-on state.
1417  */
1418 static void psmouse_cleanup(struct serio *serio)
1419 {
1420 	struct psmouse *psmouse = serio_get_drvdata(serio);
1421 	struct psmouse *parent = NULL;
1422 
1423 	mutex_lock(&psmouse_mutex);
1424 
1425 	if (serio->parent && serio->id.type == SERIO_PS_PSTHRU) {
1426 		parent = serio_get_drvdata(serio->parent);
1427 		psmouse_deactivate(parent);
1428 	}
1429 
1430 	psmouse_set_state(psmouse, PSMOUSE_INITIALIZING);
1431 
1432 	/*
1433 	 * Disable stream mode so cleanup routine can proceed undisturbed.
1434 	 */
1435 	if (ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_DISABLE))
1436 		psmouse_warn(psmouse, "Failed to disable mouse on %s\n",
1437 			     psmouse->ps2dev.serio->phys);
1438 
1439 	if (psmouse->cleanup)
1440 		psmouse->cleanup(psmouse);
1441 
1442 	/*
1443 	 * Reset the mouse to defaults (bare PS/2 protocol).
1444 	 */
1445 	ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_RESET_DIS);
1446 
1447 	/*
1448 	 * Some boxes, such as HP nx7400, get terribly confused if mouse
1449 	 * is not fully enabled before suspending/shutting down.
1450 	 */
1451 	ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_ENABLE);
1452 
1453 	if (parent) {
1454 		if (parent->pt_deactivate)
1455 			parent->pt_deactivate(parent);
1456 
1457 		psmouse_activate(parent);
1458 	}
1459 
1460 	mutex_unlock(&psmouse_mutex);
1461 }
1462 
1463 /*
1464  * psmouse_disconnect() closes and frees.
1465  */
1466 static void psmouse_disconnect(struct serio *serio)
1467 {
1468 	struct psmouse *psmouse = serio_get_drvdata(serio);
1469 	struct psmouse *parent = NULL;
1470 
1471 	sysfs_remove_group(&serio->dev.kobj, &psmouse_attribute_group);
1472 
1473 	mutex_lock(&psmouse_mutex);
1474 
1475 	psmouse_set_state(psmouse, PSMOUSE_CMD_MODE);
1476 
1477 	/* make sure we don't have a resync in progress */
1478 	mutex_unlock(&psmouse_mutex);
1479 	flush_workqueue(kpsmoused_wq);
1480 	mutex_lock(&psmouse_mutex);
1481 
1482 	if (serio->parent && serio->id.type == SERIO_PS_PSTHRU) {
1483 		parent = serio_get_drvdata(serio->parent);
1484 		psmouse_deactivate(parent);
1485 	}
1486 
1487 	if (psmouse->disconnect)
1488 		psmouse->disconnect(psmouse);
1489 
1490 	if (parent && parent->pt_deactivate)
1491 		parent->pt_deactivate(parent);
1492 
1493 	psmouse_set_state(psmouse, PSMOUSE_IGNORE);
1494 
1495 	serio_close(serio);
1496 	serio_set_drvdata(serio, NULL);
1497 
1498 	if (psmouse->dev)
1499 		input_unregister_device(psmouse->dev);
1500 
1501 	kfree(psmouse);
1502 
1503 	if (parent)
1504 		psmouse_activate(parent);
1505 
1506 	mutex_unlock(&psmouse_mutex);
1507 }
1508 
1509 static int psmouse_switch_protocol(struct psmouse *psmouse,
1510 				   const struct psmouse_protocol *proto)
1511 {
1512 	const struct psmouse_protocol *selected_proto;
1513 	struct input_dev *input_dev = psmouse->dev;
1514 	enum psmouse_type type;
1515 
1516 	input_dev->dev.parent = &psmouse->ps2dev.serio->dev;
1517 
1518 	if (proto && (proto->detect || proto->init)) {
1519 		psmouse_apply_defaults(psmouse);
1520 
1521 		if (proto->detect && proto->detect(psmouse, true) < 0)
1522 			return -1;
1523 
1524 		if (proto->init && proto->init(psmouse) < 0)
1525 			return -1;
1526 
1527 		selected_proto = proto;
1528 	} else {
1529 		type = psmouse_extensions(psmouse, psmouse_max_proto, true);
1530 		selected_proto = psmouse_protocol_by_type(type);
1531 	}
1532 
1533 	psmouse->protocol = selected_proto;
1534 
1535 	/*
1536 	 * If mouse's packet size is 3 there is no point in polling the
1537 	 * device in hopes to detect protocol reset - we won't get less
1538 	 * than 3 bytes response anyhow.
1539 	 */
1540 	if (psmouse->pktsize == 3)
1541 		psmouse->resync_time = 0;
1542 
1543 	/*
1544 	 * Some smart KVMs fake response to POLL command returning just
1545 	 * 3 bytes and messing up our resync logic, so if initial poll
1546 	 * fails we won't try polling the device anymore. Hopefully
1547 	 * such KVM will maintain initially selected protocol.
1548 	 */
1549 	if (psmouse->resync_time && psmouse->poll(psmouse))
1550 		psmouse->resync_time = 0;
1551 
1552 	snprintf(psmouse->devname, sizeof(psmouse->devname), "%s %s %s",
1553 		 selected_proto->name, psmouse->vendor, psmouse->name);
1554 
1555 	input_dev->name = psmouse->devname;
1556 	input_dev->phys = psmouse->phys;
1557 	input_dev->id.bustype = BUS_I8042;
1558 	input_dev->id.vendor = 0x0002;
1559 	input_dev->id.product = psmouse->protocol->type;
1560 	input_dev->id.version = psmouse->model;
1561 
1562 	return 0;
1563 }
1564 
1565 /*
1566  * psmouse_connect() is a callback from the serio module when
1567  * an unhandled serio port is found.
1568  */
1569 static int psmouse_connect(struct serio *serio, struct serio_driver *drv)
1570 {
1571 	struct psmouse *psmouse, *parent = NULL;
1572 	struct input_dev *input_dev;
1573 	int retval = 0, error = -ENOMEM;
1574 
1575 	mutex_lock(&psmouse_mutex);
1576 
1577 	/*
1578 	 * If this is a pass-through port deactivate parent so the device
1579 	 * connected to this port can be successfully identified
1580 	 */
1581 	if (serio->parent && serio->id.type == SERIO_PS_PSTHRU) {
1582 		parent = serio_get_drvdata(serio->parent);
1583 		psmouse_deactivate(parent);
1584 	}
1585 
1586 	psmouse = kzalloc(sizeof(struct psmouse), GFP_KERNEL);
1587 	input_dev = input_allocate_device();
1588 	if (!psmouse || !input_dev)
1589 		goto err_free;
1590 
1591 	ps2_init(&psmouse->ps2dev, serio);
1592 	INIT_DELAYED_WORK(&psmouse->resync_work, psmouse_resync);
1593 	psmouse->dev = input_dev;
1594 	snprintf(psmouse->phys, sizeof(psmouse->phys), "%s/input0", serio->phys);
1595 
1596 	psmouse_set_state(psmouse, PSMOUSE_INITIALIZING);
1597 
1598 	serio_set_drvdata(serio, psmouse);
1599 
1600 	error = serio_open(serio, drv);
1601 	if (error)
1602 		goto err_clear_drvdata;
1603 
1604 	/* give PT device some time to settle down before probing */
1605 	if (serio->id.type == SERIO_PS_PSTHRU)
1606 		usleep_range(10000, 15000);
1607 
1608 	if (psmouse_probe(psmouse) < 0) {
1609 		error = -ENODEV;
1610 		goto err_close_serio;
1611 	}
1612 
1613 	psmouse->rate = psmouse_rate;
1614 	psmouse->resolution = psmouse_resolution;
1615 	psmouse->resetafter = psmouse_resetafter;
1616 	psmouse->resync_time = parent ? 0 : psmouse_resync_time;
1617 	psmouse->smartscroll = psmouse_smartscroll;
1618 
1619 	psmouse_switch_protocol(psmouse, NULL);
1620 
1621 	if (!psmouse->protocol->smbus_companion) {
1622 		psmouse_set_state(psmouse, PSMOUSE_CMD_MODE);
1623 		psmouse_initialize(psmouse);
1624 
1625 		error = input_register_device(input_dev);
1626 		if (error)
1627 			goto err_protocol_disconnect;
1628 	} else {
1629 		/* Smbus companion will be reporting events, not us. */
1630 		input_free_device(input_dev);
1631 		psmouse->dev = input_dev = NULL;
1632 	}
1633 
1634 	if (parent && parent->pt_activate)
1635 		parent->pt_activate(parent);
1636 
1637 	error = sysfs_create_group(&serio->dev.kobj, &psmouse_attribute_group);
1638 	if (error)
1639 		goto err_pt_deactivate;
1640 
1641 	/*
1642 	 * PS/2 devices having SMBus companions should stay disabled
1643 	 * on PS/2 side, in order to have SMBus part operable.
1644 	 */
1645 	if (!psmouse->protocol->smbus_companion)
1646 		psmouse_activate(psmouse);
1647 
1648  out:
1649 	/* If this is a pass-through port the parent needs to be re-activated */
1650 	if (parent)
1651 		psmouse_activate(parent);
1652 
1653 	mutex_unlock(&psmouse_mutex);
1654 	return retval;
1655 
1656  err_pt_deactivate:
1657 	if (parent && parent->pt_deactivate)
1658 		parent->pt_deactivate(parent);
1659 	if (input_dev) {
1660 		input_unregister_device(input_dev);
1661 		input_dev = NULL; /* so we don't try to free it below */
1662 	}
1663  err_protocol_disconnect:
1664 	if (psmouse->disconnect)
1665 		psmouse->disconnect(psmouse);
1666 	psmouse_set_state(psmouse, PSMOUSE_IGNORE);
1667  err_close_serio:
1668 	serio_close(serio);
1669  err_clear_drvdata:
1670 	serio_set_drvdata(serio, NULL);
1671  err_free:
1672 	input_free_device(input_dev);
1673 	kfree(psmouse);
1674 
1675 	retval = error;
1676 	goto out;
1677 }
1678 
1679 static int __psmouse_reconnect(struct serio *serio, bool fast_reconnect)
1680 {
1681 	struct psmouse *psmouse = serio_get_drvdata(serio);
1682 	struct psmouse *parent = NULL;
1683 	int (*reconnect_handler)(struct psmouse *);
1684 	enum psmouse_type type;
1685 	int rc = -1;
1686 
1687 	mutex_lock(&psmouse_mutex);
1688 
1689 	if (fast_reconnect) {
1690 		reconnect_handler = psmouse->fast_reconnect;
1691 		if (!reconnect_handler) {
1692 			rc = -ENOENT;
1693 			goto out_unlock;
1694 		}
1695 	} else {
1696 		reconnect_handler = psmouse->reconnect;
1697 	}
1698 
1699 	if (serio->parent && serio->id.type == SERIO_PS_PSTHRU) {
1700 		parent = serio_get_drvdata(serio->parent);
1701 		psmouse_deactivate(parent);
1702 	}
1703 
1704 	psmouse_set_state(psmouse, PSMOUSE_INITIALIZING);
1705 
1706 	if (reconnect_handler) {
1707 		if (reconnect_handler(psmouse))
1708 			goto out;
1709 	} else {
1710 		psmouse_reset(psmouse);
1711 
1712 		if (psmouse_probe(psmouse) < 0)
1713 			goto out;
1714 
1715 		type = psmouse_extensions(psmouse, psmouse_max_proto, false);
1716 		if (psmouse->protocol->type != type)
1717 			goto out;
1718 	}
1719 
1720 	/*
1721 	 * OK, the device type (and capabilities) match the old one,
1722 	 * we can continue using it, complete initialization
1723 	 */
1724 	if (!psmouse->protocol->smbus_companion) {
1725 		psmouse_set_state(psmouse, PSMOUSE_CMD_MODE);
1726 		psmouse_initialize(psmouse);
1727 	}
1728 
1729 	if (parent && parent->pt_activate)
1730 		parent->pt_activate(parent);
1731 
1732 	/*
1733 	 * PS/2 devices having SMBus companions should stay disabled
1734 	 * on PS/2 side, in order to have SMBus part operable.
1735 	 */
1736 	if (!psmouse->protocol->smbus_companion)
1737 		psmouse_activate(psmouse);
1738 
1739 	rc = 0;
1740 
1741 out:
1742 	/* If this is a pass-through port the parent waits to be activated */
1743 	if (parent)
1744 		psmouse_activate(parent);
1745 
1746 out_unlock:
1747 	mutex_unlock(&psmouse_mutex);
1748 	return rc;
1749 }
1750 
1751 static int psmouse_reconnect(struct serio *serio)
1752 {
1753 	return __psmouse_reconnect(serio, false);
1754 }
1755 
1756 static int psmouse_fast_reconnect(struct serio *serio)
1757 {
1758 	return __psmouse_reconnect(serio, true);
1759 }
1760 
1761 static struct serio_device_id psmouse_serio_ids[] = {
1762 	{
1763 		.type	= SERIO_8042,
1764 		.proto	= SERIO_ANY,
1765 		.id	= SERIO_ANY,
1766 		.extra	= SERIO_ANY,
1767 	},
1768 	{
1769 		.type	= SERIO_PS_PSTHRU,
1770 		.proto	= SERIO_ANY,
1771 		.id	= SERIO_ANY,
1772 		.extra	= SERIO_ANY,
1773 	},
1774 	{ 0 }
1775 };
1776 
1777 MODULE_DEVICE_TABLE(serio, psmouse_serio_ids);
1778 
1779 static struct serio_driver psmouse_drv = {
1780 	.driver		= {
1781 		.name	= "psmouse",
1782 	},
1783 	.description	= DRIVER_DESC,
1784 	.id_table	= psmouse_serio_ids,
1785 	.interrupt	= psmouse_interrupt,
1786 	.connect	= psmouse_connect,
1787 	.reconnect	= psmouse_reconnect,
1788 	.fast_reconnect	= psmouse_fast_reconnect,
1789 	.disconnect	= psmouse_disconnect,
1790 	.cleanup	= psmouse_cleanup,
1791 };
1792 
1793 ssize_t psmouse_attr_show_helper(struct device *dev, struct device_attribute *devattr,
1794 				 char *buf)
1795 {
1796 	struct serio *serio = to_serio_port(dev);
1797 	struct psmouse_attribute *attr = to_psmouse_attr(devattr);
1798 	struct psmouse *psmouse = serio_get_drvdata(serio);
1799 
1800 	if (psmouse->protocol->smbus_companion &&
1801 			devattr != &psmouse_attr_protocol.dattr)
1802 		return -ENOENT;
1803 
1804 	return attr->show(psmouse, attr->data, buf);
1805 }
1806 
1807 ssize_t psmouse_attr_set_helper(struct device *dev, struct device_attribute *devattr,
1808 				const char *buf, size_t count)
1809 {
1810 	struct serio *serio = to_serio_port(dev);
1811 	struct psmouse_attribute *attr = to_psmouse_attr(devattr);
1812 	struct psmouse *psmouse, *parent = NULL;
1813 	int retval;
1814 
1815 	retval = mutex_lock_interruptible(&psmouse_mutex);
1816 	if (retval)
1817 		goto out;
1818 
1819 	psmouse = serio_get_drvdata(serio);
1820 
1821 	if (psmouse->protocol->smbus_companion &&
1822 			devattr != &psmouse_attr_protocol.dattr) {
1823 		retval = -ENOENT;
1824 		goto out_unlock;
1825 	}
1826 
1827 	if (attr->protect) {
1828 		if (psmouse->state == PSMOUSE_IGNORE) {
1829 			retval = -ENODEV;
1830 			goto out_unlock;
1831 		}
1832 
1833 		if (serio->parent && serio->id.type == SERIO_PS_PSTHRU) {
1834 			parent = serio_get_drvdata(serio->parent);
1835 			psmouse_deactivate(parent);
1836 		}
1837 
1838 		if (!psmouse->protocol->smbus_companion)
1839 			psmouse_deactivate(psmouse);
1840 	}
1841 
1842 	retval = attr->set(psmouse, attr->data, buf, count);
1843 
1844 	if (attr->protect) {
1845 		if (retval != -ENODEV && !psmouse->protocol->smbus_companion)
1846 			psmouse_activate(psmouse);
1847 
1848 		if (parent)
1849 			psmouse_activate(parent);
1850 	}
1851 
1852  out_unlock:
1853 	mutex_unlock(&psmouse_mutex);
1854  out:
1855 	return retval;
1856 }
1857 
1858 static ssize_t psmouse_show_int_attr(struct psmouse *psmouse, void *offset, char *buf)
1859 {
1860 	unsigned int *field = (unsigned int *)((char *)psmouse + (size_t)offset);
1861 
1862 	return sprintf(buf, "%u\n", *field);
1863 }
1864 
1865 static ssize_t psmouse_set_int_attr(struct psmouse *psmouse, void *offset, const char *buf, size_t count)
1866 {
1867 	unsigned int *field = (unsigned int *)((char *)psmouse + (size_t)offset);
1868 	unsigned int value;
1869 	int err;
1870 
1871 	err = kstrtouint(buf, 10, &value);
1872 	if (err)
1873 		return err;
1874 
1875 	*field = value;
1876 
1877 	return count;
1878 }
1879 
1880 static ssize_t psmouse_attr_show_protocol(struct psmouse *psmouse, void *data, char *buf)
1881 {
1882 	return sprintf(buf, "%s\n", psmouse->protocol->name);
1883 }
1884 
1885 static ssize_t psmouse_attr_set_protocol(struct psmouse *psmouse, void *data, const char *buf, size_t count)
1886 {
1887 	struct serio *serio = psmouse->ps2dev.serio;
1888 	struct psmouse *parent = NULL;
1889 	struct input_dev *old_dev, *new_dev;
1890 	const struct psmouse_protocol *proto, *old_proto;
1891 	int error;
1892 	int retry = 0;
1893 
1894 	proto = psmouse_protocol_by_name(buf, count);
1895 	if (!proto)
1896 		return -EINVAL;
1897 
1898 	if (psmouse->protocol == proto)
1899 		return count;
1900 
1901 	new_dev = input_allocate_device();
1902 	if (!new_dev)
1903 		return -ENOMEM;
1904 
1905 	while (!list_empty(&serio->children)) {
1906 		if (++retry > 3) {
1907 			psmouse_warn(psmouse,
1908 				     "failed to destroy children ports, protocol change aborted.\n");
1909 			input_free_device(new_dev);
1910 			return -EIO;
1911 		}
1912 
1913 		mutex_unlock(&psmouse_mutex);
1914 		serio_unregister_child_port(serio);
1915 		mutex_lock(&psmouse_mutex);
1916 
1917 		if (serio->drv != &psmouse_drv) {
1918 			input_free_device(new_dev);
1919 			return -ENODEV;
1920 		}
1921 
1922 		if (psmouse->protocol == proto) {
1923 			input_free_device(new_dev);
1924 			return count; /* switched by other thread */
1925 		}
1926 	}
1927 
1928 	if (serio->parent && serio->id.type == SERIO_PS_PSTHRU) {
1929 		parent = serio_get_drvdata(serio->parent);
1930 		if (parent->pt_deactivate)
1931 			parent->pt_deactivate(parent);
1932 	}
1933 
1934 	old_dev = psmouse->dev;
1935 	old_proto = psmouse->protocol;
1936 
1937 	if (psmouse->disconnect)
1938 		psmouse->disconnect(psmouse);
1939 
1940 	psmouse_set_state(psmouse, PSMOUSE_IGNORE);
1941 
1942 	psmouse->dev = new_dev;
1943 	psmouse_set_state(psmouse, PSMOUSE_INITIALIZING);
1944 
1945 	if (psmouse_switch_protocol(psmouse, proto) < 0) {
1946 		psmouse_reset(psmouse);
1947 		/* default to PSMOUSE_PS2 */
1948 		psmouse_switch_protocol(psmouse, &psmouse_protocols[0]);
1949 	}
1950 
1951 	psmouse_initialize(psmouse);
1952 	psmouse_set_state(psmouse, PSMOUSE_CMD_MODE);
1953 
1954 	if (psmouse->protocol->smbus_companion) {
1955 		input_free_device(psmouse->dev);
1956 		psmouse->dev = NULL;
1957 	} else {
1958 		error = input_register_device(psmouse->dev);
1959 		if (error) {
1960 			if (psmouse->disconnect)
1961 				psmouse->disconnect(psmouse);
1962 
1963 			psmouse_set_state(psmouse, PSMOUSE_IGNORE);
1964 			input_free_device(new_dev);
1965 			psmouse->dev = old_dev;
1966 			psmouse_set_state(psmouse, PSMOUSE_INITIALIZING);
1967 			psmouse_switch_protocol(psmouse, old_proto);
1968 			psmouse_initialize(psmouse);
1969 			psmouse_set_state(psmouse, PSMOUSE_CMD_MODE);
1970 
1971 			return error;
1972 		}
1973 	}
1974 
1975 	if (old_dev)
1976 		input_unregister_device(old_dev);
1977 
1978 	if (parent && parent->pt_activate)
1979 		parent->pt_activate(parent);
1980 
1981 	return count;
1982 }
1983 
1984 static ssize_t psmouse_attr_set_rate(struct psmouse *psmouse, void *data, const char *buf, size_t count)
1985 {
1986 	unsigned int value;
1987 	int err;
1988 
1989 	err = kstrtouint(buf, 10, &value);
1990 	if (err)
1991 		return err;
1992 
1993 	psmouse->set_rate(psmouse, value);
1994 	return count;
1995 }
1996 
1997 static ssize_t psmouse_attr_set_resolution(struct psmouse *psmouse, void *data, const char *buf, size_t count)
1998 {
1999 	unsigned int value;
2000 	int err;
2001 
2002 	err = kstrtouint(buf, 10, &value);
2003 	if (err)
2004 		return err;
2005 
2006 	psmouse->set_resolution(psmouse, value);
2007 	return count;
2008 }
2009 
2010 
2011 static int psmouse_set_maxproto(const char *val, const struct kernel_param *kp)
2012 {
2013 	const struct psmouse_protocol *proto;
2014 
2015 	if (!val)
2016 		return -EINVAL;
2017 
2018 	proto = psmouse_protocol_by_name(val, strlen(val));
2019 
2020 	if (!proto || !proto->maxproto)
2021 		return -EINVAL;
2022 
2023 	*((unsigned int *)kp->arg) = proto->type;
2024 
2025 	return 0;
2026 }
2027 
2028 static int psmouse_get_maxproto(char *buffer, const struct kernel_param *kp)
2029 {
2030 	int type = *((unsigned int *)kp->arg);
2031 
2032 	return sprintf(buffer, "%s", psmouse_protocol_by_type(type)->name);
2033 }
2034 
2035 static int __init psmouse_init(void)
2036 {
2037 	int err;
2038 
2039 	lifebook_module_init();
2040 	synaptics_module_init();
2041 	hgpk_module_init();
2042 
2043 	err = psmouse_smbus_module_init();
2044 	if (err)
2045 		return err;
2046 
2047 	kpsmoused_wq = alloc_ordered_workqueue("kpsmoused", 0);
2048 	if (!kpsmoused_wq) {
2049 		pr_err("failed to create kpsmoused workqueue\n");
2050 		err = -ENOMEM;
2051 		goto err_smbus_exit;
2052 	}
2053 
2054 	err = serio_register_driver(&psmouse_drv);
2055 	if (err)
2056 		goto err_destroy_wq;
2057 
2058 	return 0;
2059 
2060 err_destroy_wq:
2061 	destroy_workqueue(kpsmoused_wq);
2062 err_smbus_exit:
2063 	psmouse_smbus_module_exit();
2064 	return err;
2065 }
2066 
2067 static void __exit psmouse_exit(void)
2068 {
2069 	serio_unregister_driver(&psmouse_drv);
2070 	destroy_workqueue(kpsmoused_wq);
2071 	psmouse_smbus_module_exit();
2072 }
2073 
2074 module_init(psmouse_init);
2075 module_exit(psmouse_exit);
2076