xref: /linux/drivers/input/serio/i8042.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  i8042 keyboard and mouse controller driver for Linux
4  *
5  *  Copyright (c) 1999-2004 Vojtech Pavlik
6  */
7 
8 
9 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
10 
11 #include <linux/types.h>
12 #include <linux/delay.h>
13 #include <linux/module.h>
14 #include <linux/interrupt.h>
15 #include <linux/ioport.h>
16 #include <linux/init.h>
17 #include <linux/serio.h>
18 #include <linux/err.h>
19 #include <linux/rcupdate.h>
20 #include <linux/platform_device.h>
21 #include <linux/i8042.h>
22 #include <linux/slab.h>
23 #include <linux/suspend.h>
24 #include <linux/property.h>
25 
26 #include <asm/io.h>
27 
28 MODULE_AUTHOR("Vojtech Pavlik <vojtech@suse.cz>");
29 MODULE_DESCRIPTION("i8042 keyboard and mouse controller driver");
30 MODULE_LICENSE("GPL");
31 
32 static bool i8042_nokbd;
33 module_param_named(nokbd, i8042_nokbd, bool, 0);
34 MODULE_PARM_DESC(nokbd, "Do not probe or use KBD port.");
35 
36 static bool i8042_noaux;
37 module_param_named(noaux, i8042_noaux, bool, 0);
38 MODULE_PARM_DESC(noaux, "Do not probe or use AUX (mouse) port.");
39 
40 static bool i8042_nomux;
41 module_param_named(nomux, i8042_nomux, bool, 0);
42 MODULE_PARM_DESC(nomux, "Do not check whether an active multiplexing controller is present.");
43 
44 static bool i8042_unlock;
45 module_param_named(unlock, i8042_unlock, bool, 0);
46 MODULE_PARM_DESC(unlock, "Ignore keyboard lock.");
47 
48 static bool i8042_probe_defer;
49 module_param_named(probe_defer, i8042_probe_defer, bool, 0);
50 MODULE_PARM_DESC(probe_defer, "Allow deferred probing.");
51 
52 enum i8042_controller_reset_mode {
53 	I8042_RESET_NEVER,
54 	I8042_RESET_ALWAYS,
55 	I8042_RESET_ON_S2RAM,
56 #define I8042_RESET_DEFAULT	I8042_RESET_ON_S2RAM
57 };
58 static enum i8042_controller_reset_mode i8042_reset = I8042_RESET_DEFAULT;
59 static int i8042_set_reset(const char *val, const struct kernel_param *kp)
60 {
61 	enum i8042_controller_reset_mode *arg = kp->arg;
62 	int error;
63 	bool reset;
64 
65 	if (val) {
66 		error = kstrtobool(val, &reset);
67 		if (error)
68 			return error;
69 	} else {
70 		reset = true;
71 	}
72 
73 	*arg = reset ? I8042_RESET_ALWAYS : I8042_RESET_NEVER;
74 	return 0;
75 }
76 
77 static const struct kernel_param_ops param_ops_reset_param = {
78 	.flags = KERNEL_PARAM_OPS_FL_NOARG,
79 	.set = i8042_set_reset,
80 };
81 #define param_check_reset_param(name, p)	\
82 	__param_check(name, p, enum i8042_controller_reset_mode)
83 module_param_named(reset, i8042_reset, reset_param, 0);
84 MODULE_PARM_DESC(reset, "Reset controller on resume, cleanup or both");
85 
86 static bool i8042_direct;
87 module_param_named(direct, i8042_direct, bool, 0);
88 MODULE_PARM_DESC(direct, "Put keyboard port into non-translated mode.");
89 
90 static bool i8042_dumbkbd;
91 module_param_named(dumbkbd, i8042_dumbkbd, bool, 0);
92 MODULE_PARM_DESC(dumbkbd, "Pretend that controller can only read data from keyboard");
93 
94 static bool i8042_noloop;
95 module_param_named(noloop, i8042_noloop, bool, 0);
96 MODULE_PARM_DESC(noloop, "Disable the AUX Loopback command while probing for the AUX port");
97 
98 static bool i8042_notimeout;
99 module_param_named(notimeout, i8042_notimeout, bool, 0);
100 MODULE_PARM_DESC(notimeout, "Ignore timeouts signalled by i8042");
101 
102 static bool i8042_kbdreset;
103 module_param_named(kbdreset, i8042_kbdreset, bool, 0);
104 MODULE_PARM_DESC(kbdreset, "Reset device connected to KBD port");
105 
106 #ifdef CONFIG_X86
107 static bool i8042_dritek;
108 module_param_named(dritek, i8042_dritek, bool, 0);
109 MODULE_PARM_DESC(dritek, "Force enable the Dritek keyboard extension");
110 #endif
111 
112 #ifdef CONFIG_PNP
113 static bool i8042_nopnp;
114 module_param_named(nopnp, i8042_nopnp, bool, 0);
115 MODULE_PARM_DESC(nopnp, "Do not use PNP to detect controller settings");
116 #endif
117 
118 static bool i8042_forcenorestore;
119 module_param_named(forcenorestore, i8042_forcenorestore, bool, 0);
120 MODULE_PARM_DESC(forcenorestore, "Force no restore on s3 resume, copying s2idle behaviour");
121 
122 #define DEBUG
123 #ifdef DEBUG
124 static bool i8042_debug;
125 module_param_named(debug, i8042_debug, bool, 0600);
126 MODULE_PARM_DESC(debug, "Turn i8042 debugging mode on and off");
127 
128 static bool i8042_unmask_kbd_data;
129 module_param_named(unmask_kbd_data, i8042_unmask_kbd_data, bool, 0600);
130 MODULE_PARM_DESC(unmask_kbd_data, "Unconditional enable (may reveal sensitive data) of normally sanitize-filtered kbd data traffic debug log [pre-condition: i8042.debug=1 enabled]");
131 #endif
132 
133 static bool i8042_present;
134 static bool i8042_bypass_aux_irq_test;
135 static char i8042_kbd_firmware_id[128];
136 static char i8042_aux_firmware_id[128];
137 static struct fwnode_handle *i8042_kbd_fwnode;
138 
139 #include "i8042.h"
140 
141 /*
142  * i8042_lock protects serialization between i8042_command and
143  * the interrupt handler.
144  */
145 static DEFINE_SPINLOCK(i8042_lock);
146 
147 /*
148  * Writers to AUX and KBD ports as well as users issuing i8042_command
149  * directly should acquire i8042_mutex (by means of calling
150  * i8042_lock_chip() and i8042_unlock_chip() helpers) to ensure that
151  * they do not disturb each other (unfortunately in many i8042
152  * implementations write to one of the ports will immediately abort
153  * command that is being processed by another port).
154  */
155 static DEFINE_MUTEX(i8042_mutex);
156 
157 struct i8042_port {
158 	struct serio *serio;
159 	int irq;
160 	bool exists;
161 	bool driver_bound;
162 	signed char mux;
163 };
164 
165 #define I8042_KBD_PORT_NO	0
166 #define I8042_AUX_PORT_NO	1
167 #define I8042_MUX_PORT_NO	2
168 #define I8042_NUM_PORTS		(I8042_NUM_MUX_PORTS + 2)
169 
170 static struct i8042_port i8042_ports[I8042_NUM_PORTS];
171 
172 static unsigned char i8042_initial_ctr;
173 static unsigned char i8042_ctr;
174 static bool i8042_mux_present;
175 static bool i8042_kbd_irq_registered;
176 static bool i8042_aux_irq_registered;
177 static unsigned char i8042_suppress_kbd_ack;
178 static struct platform_device *i8042_platform_device;
179 static struct notifier_block i8042_kbd_bind_notifier_block;
180 
181 static irqreturn_t i8042_interrupt(int irq, void *dev_id);
182 static bool (*i8042_platform_filter)(unsigned char data, unsigned char str,
183 				     struct serio *serio);
184 
185 void i8042_lock_chip(void)
186 {
187 	mutex_lock(&i8042_mutex);
188 }
189 EXPORT_SYMBOL(i8042_lock_chip);
190 
191 void i8042_unlock_chip(void)
192 {
193 	mutex_unlock(&i8042_mutex);
194 }
195 EXPORT_SYMBOL(i8042_unlock_chip);
196 
197 int i8042_install_filter(bool (*filter)(unsigned char data, unsigned char str,
198 					struct serio *serio))
199 {
200 	unsigned long flags;
201 	int ret = 0;
202 
203 	spin_lock_irqsave(&i8042_lock, flags);
204 
205 	if (i8042_platform_filter) {
206 		ret = -EBUSY;
207 		goto out;
208 	}
209 
210 	i8042_platform_filter = filter;
211 
212 out:
213 	spin_unlock_irqrestore(&i8042_lock, flags);
214 	return ret;
215 }
216 EXPORT_SYMBOL(i8042_install_filter);
217 
218 int i8042_remove_filter(bool (*filter)(unsigned char data, unsigned char str,
219 				       struct serio *port))
220 {
221 	unsigned long flags;
222 	int ret = 0;
223 
224 	spin_lock_irqsave(&i8042_lock, flags);
225 
226 	if (i8042_platform_filter != filter) {
227 		ret = -EINVAL;
228 		goto out;
229 	}
230 
231 	i8042_platform_filter = NULL;
232 
233 out:
234 	spin_unlock_irqrestore(&i8042_lock, flags);
235 	return ret;
236 }
237 EXPORT_SYMBOL(i8042_remove_filter);
238 
239 /*
240  * The i8042_wait_read() and i8042_wait_write functions wait for the i8042 to
241  * be ready for reading values from it / writing values to it.
242  * Called always with i8042_lock held.
243  */
244 
245 static int i8042_wait_read(void)
246 {
247 	int i = 0;
248 
249 	while ((~i8042_read_status() & I8042_STR_OBF) && (i < I8042_CTL_TIMEOUT)) {
250 		udelay(50);
251 		i++;
252 	}
253 	return -(i == I8042_CTL_TIMEOUT);
254 }
255 
256 static int i8042_wait_write(void)
257 {
258 	int i = 0;
259 
260 	while ((i8042_read_status() & I8042_STR_IBF) && (i < I8042_CTL_TIMEOUT)) {
261 		udelay(50);
262 		i++;
263 	}
264 	return -(i == I8042_CTL_TIMEOUT);
265 }
266 
267 /*
268  * i8042_flush() flushes all data that may be in the keyboard and mouse buffers
269  * of the i8042 down the toilet.
270  */
271 
272 static int i8042_flush(void)
273 {
274 	unsigned long flags;
275 	unsigned char data, str;
276 	int count = 0;
277 	int retval = 0;
278 
279 	spin_lock_irqsave(&i8042_lock, flags);
280 
281 	while ((str = i8042_read_status()) & I8042_STR_OBF) {
282 		if (count++ < I8042_BUFFER_SIZE) {
283 			udelay(50);
284 			data = i8042_read_data();
285 			dbg("%02x <- i8042 (flush, %s)\n",
286 			    data, str & I8042_STR_AUXDATA ? "aux" : "kbd");
287 		} else {
288 			retval = -EIO;
289 			break;
290 		}
291 	}
292 
293 	spin_unlock_irqrestore(&i8042_lock, flags);
294 
295 	return retval;
296 }
297 
298 /*
299  * i8042_command() executes a command on the i8042. It also sends the input
300  * parameter(s) of the commands to it, and receives the output value(s). The
301  * parameters are to be stored in the param array, and the output is placed
302  * into the same array. The number of the parameters and output values is
303  * encoded in bits 8-11 of the command number.
304  */
305 
306 static int __i8042_command(unsigned char *param, int command)
307 {
308 	int i, error;
309 
310 	if (i8042_noloop && command == I8042_CMD_AUX_LOOP)
311 		return -1;
312 
313 	error = i8042_wait_write();
314 	if (error)
315 		return error;
316 
317 	dbg("%02x -> i8042 (command)\n", command & 0xff);
318 	i8042_write_command(command & 0xff);
319 
320 	for (i = 0; i < ((command >> 12) & 0xf); i++) {
321 		error = i8042_wait_write();
322 		if (error) {
323 			dbg("     -- i8042 (wait write timeout)\n");
324 			return error;
325 		}
326 		dbg("%02x -> i8042 (parameter)\n", param[i]);
327 		i8042_write_data(param[i]);
328 	}
329 
330 	for (i = 0; i < ((command >> 8) & 0xf); i++) {
331 		error = i8042_wait_read();
332 		if (error) {
333 			dbg("     -- i8042 (wait read timeout)\n");
334 			return error;
335 		}
336 
337 		if (command == I8042_CMD_AUX_LOOP &&
338 		    !(i8042_read_status() & I8042_STR_AUXDATA)) {
339 			dbg("     -- i8042 (auxerr)\n");
340 			return -1;
341 		}
342 
343 		param[i] = i8042_read_data();
344 		dbg("%02x <- i8042 (return)\n", param[i]);
345 	}
346 
347 	return 0;
348 }
349 
350 int i8042_command(unsigned char *param, int command)
351 {
352 	unsigned long flags;
353 	int retval;
354 
355 	if (!i8042_present)
356 		return -1;
357 
358 	spin_lock_irqsave(&i8042_lock, flags);
359 	retval = __i8042_command(param, command);
360 	spin_unlock_irqrestore(&i8042_lock, flags);
361 
362 	return retval;
363 }
364 EXPORT_SYMBOL(i8042_command);
365 
366 /*
367  * i8042_kbd_write() sends a byte out through the keyboard interface.
368  */
369 
370 static int i8042_kbd_write(struct serio *port, unsigned char c)
371 {
372 	unsigned long flags;
373 	int retval = 0;
374 
375 	spin_lock_irqsave(&i8042_lock, flags);
376 
377 	if (!(retval = i8042_wait_write())) {
378 		dbg("%02x -> i8042 (kbd-data)\n", c);
379 		i8042_write_data(c);
380 	}
381 
382 	spin_unlock_irqrestore(&i8042_lock, flags);
383 
384 	return retval;
385 }
386 
387 /*
388  * i8042_aux_write() sends a byte out through the aux interface.
389  */
390 
391 static int i8042_aux_write(struct serio *serio, unsigned char c)
392 {
393 	struct i8042_port *port = serio->port_data;
394 
395 	return i8042_command(&c, port->mux == -1 ?
396 					I8042_CMD_AUX_SEND :
397 					I8042_CMD_MUX_SEND + port->mux);
398 }
399 
400 
401 /*
402  * i8042_port_close attempts to clear AUX or KBD port state by disabling
403  * and then re-enabling it.
404  */
405 
406 static void i8042_port_close(struct serio *serio)
407 {
408 	int irq_bit;
409 	int disable_bit;
410 	const char *port_name;
411 
412 	if (serio == i8042_ports[I8042_AUX_PORT_NO].serio) {
413 		irq_bit = I8042_CTR_AUXINT;
414 		disable_bit = I8042_CTR_AUXDIS;
415 		port_name = "AUX";
416 	} else {
417 		irq_bit = I8042_CTR_KBDINT;
418 		disable_bit = I8042_CTR_KBDDIS;
419 		port_name = "KBD";
420 	}
421 
422 	i8042_ctr &= ~irq_bit;
423 	if (i8042_command(&i8042_ctr, I8042_CMD_CTL_WCTR))
424 		pr_warn("Can't write CTR while closing %s port\n", port_name);
425 
426 	udelay(50);
427 
428 	i8042_ctr &= ~disable_bit;
429 	i8042_ctr |= irq_bit;
430 	if (i8042_command(&i8042_ctr, I8042_CMD_CTL_WCTR))
431 		pr_err("Can't reactivate %s port\n", port_name);
432 
433 	/*
434 	 * See if there is any data appeared while we were messing with
435 	 * port state.
436 	 */
437 	i8042_interrupt(0, NULL);
438 }
439 
440 /*
441  * i8042_start() is called by serio core when port is about to finish
442  * registering. It will mark port as existing so i8042_interrupt can
443  * start sending data through it.
444  */
445 static int i8042_start(struct serio *serio)
446 {
447 	struct i8042_port *port = serio->port_data;
448 
449 	device_set_wakeup_capable(&serio->dev, true);
450 
451 	/*
452 	 * On platforms using suspend-to-idle, allow the keyboard to
453 	 * wake up the system from sleep by enabling keyboard wakeups
454 	 * by default.  This is consistent with keyboard wakeup
455 	 * behavior on many platforms using suspend-to-RAM (ACPI S3)
456 	 * by default.
457 	 */
458 	if (pm_suspend_default_s2idle() &&
459 	    serio == i8042_ports[I8042_KBD_PORT_NO].serio) {
460 		device_set_wakeup_enable(&serio->dev, true);
461 	}
462 
463 	spin_lock_irq(&i8042_lock);
464 	port->exists = true;
465 	spin_unlock_irq(&i8042_lock);
466 
467 	return 0;
468 }
469 
470 /*
471  * i8042_stop() marks serio port as non-existing so i8042_interrupt
472  * will not try to send data to the port that is about to go away.
473  * The function is called by serio core as part of unregister procedure.
474  */
475 static void i8042_stop(struct serio *serio)
476 {
477 	struct i8042_port *port = serio->port_data;
478 
479 	spin_lock_irq(&i8042_lock);
480 	port->exists = false;
481 	port->serio = NULL;
482 	spin_unlock_irq(&i8042_lock);
483 
484 	/*
485 	 * We need to make sure that interrupt handler finishes using
486 	 * our serio port before we return from this function.
487 	 * We synchronize with both AUX and KBD IRQs because there is
488 	 * a (very unlikely) chance that AUX IRQ is raised for KBD port
489 	 * and vice versa.
490 	 */
491 	synchronize_irq(I8042_AUX_IRQ);
492 	synchronize_irq(I8042_KBD_IRQ);
493 }
494 
495 /*
496  * i8042_filter() filters out unwanted bytes from the input data stream.
497  * It is called from i8042_interrupt and thus is running with interrupts
498  * off and i8042_lock held.
499  */
500 static bool i8042_filter(unsigned char data, unsigned char str,
501 			 struct serio *serio)
502 {
503 	if (unlikely(i8042_suppress_kbd_ack)) {
504 		if ((~str & I8042_STR_AUXDATA) &&
505 		    (data == 0xfa || data == 0xfe)) {
506 			i8042_suppress_kbd_ack--;
507 			dbg("Extra keyboard ACK - filtered out\n");
508 			return true;
509 		}
510 	}
511 
512 	if (i8042_platform_filter && i8042_platform_filter(data, str, serio)) {
513 		dbg("Filtered out by platform filter\n");
514 		return true;
515 	}
516 
517 	return false;
518 }
519 
520 /*
521  * i8042_interrupt() is the most important function in this driver -
522  * it handles the interrupts from the i8042, and sends incoming bytes
523  * to the upper layers.
524  */
525 
526 static irqreturn_t i8042_interrupt(int irq, void *dev_id)
527 {
528 	struct i8042_port *port;
529 	struct serio *serio;
530 	unsigned long flags;
531 	unsigned char str, data;
532 	unsigned int dfl;
533 	unsigned int port_no;
534 	bool filtered;
535 	int ret = 1;
536 
537 	spin_lock_irqsave(&i8042_lock, flags);
538 
539 	str = i8042_read_status();
540 	if (unlikely(~str & I8042_STR_OBF)) {
541 		spin_unlock_irqrestore(&i8042_lock, flags);
542 		if (irq)
543 			dbg("Interrupt %d, without any data\n", irq);
544 		ret = 0;
545 		goto out;
546 	}
547 
548 	data = i8042_read_data();
549 
550 	if (i8042_mux_present && (str & I8042_STR_AUXDATA)) {
551 		static unsigned long last_transmit;
552 		static unsigned char last_str;
553 
554 		dfl = 0;
555 		if (str & I8042_STR_MUXERR) {
556 			dbg("MUX error, status is %02x, data is %02x\n",
557 			    str, data);
558 /*
559  * When MUXERR condition is signalled the data register can only contain
560  * 0xfd, 0xfe or 0xff if implementation follows the spec. Unfortunately
561  * it is not always the case. Some KBCs also report 0xfc when there is
562  * nothing connected to the port while others sometimes get confused which
563  * port the data came from and signal error leaving the data intact. They
564  * _do not_ revert to legacy mode (actually I've never seen KBC reverting
565  * to legacy mode yet, when we see one we'll add proper handling).
566  * Anyway, we process 0xfc, 0xfd, 0xfe and 0xff as timeouts, and for the
567  * rest assume that the data came from the same serio last byte
568  * was transmitted (if transmission happened not too long ago).
569  */
570 
571 			switch (data) {
572 				default:
573 					if (time_before(jiffies, last_transmit + HZ/10)) {
574 						str = last_str;
575 						break;
576 					}
577 					fallthrough;	/* report timeout */
578 				case 0xfc:
579 				case 0xfd:
580 				case 0xfe: dfl = SERIO_TIMEOUT; data = 0xfe; break;
581 				case 0xff: dfl = SERIO_PARITY;  data = 0xfe; break;
582 			}
583 		}
584 
585 		port_no = I8042_MUX_PORT_NO + ((str >> 6) & 3);
586 		last_str = str;
587 		last_transmit = jiffies;
588 	} else {
589 
590 		dfl = ((str & I8042_STR_PARITY) ? SERIO_PARITY : 0) |
591 		      ((str & I8042_STR_TIMEOUT && !i8042_notimeout) ? SERIO_TIMEOUT : 0);
592 
593 		port_no = (str & I8042_STR_AUXDATA) ?
594 				I8042_AUX_PORT_NO : I8042_KBD_PORT_NO;
595 	}
596 
597 	port = &i8042_ports[port_no];
598 	serio = port->exists ? port->serio : NULL;
599 
600 	filter_dbg(port->driver_bound, data, "<- i8042 (interrupt, %d, %d%s%s)\n",
601 		   port_no, irq,
602 		   dfl & SERIO_PARITY ? ", bad parity" : "",
603 		   dfl & SERIO_TIMEOUT ? ", timeout" : "");
604 
605 	filtered = i8042_filter(data, str, serio);
606 
607 	spin_unlock_irqrestore(&i8042_lock, flags);
608 
609 	if (likely(serio && !filtered))
610 		serio_interrupt(serio, data, dfl);
611 
612  out:
613 	return IRQ_RETVAL(ret);
614 }
615 
616 /*
617  * i8042_enable_kbd_port enables keyboard port on chip
618  */
619 
620 static int i8042_enable_kbd_port(void)
621 {
622 	i8042_ctr &= ~I8042_CTR_KBDDIS;
623 	i8042_ctr |= I8042_CTR_KBDINT;
624 
625 	if (i8042_command(&i8042_ctr, I8042_CMD_CTL_WCTR)) {
626 		i8042_ctr &= ~I8042_CTR_KBDINT;
627 		i8042_ctr |= I8042_CTR_KBDDIS;
628 		pr_err("Failed to enable KBD port\n");
629 		return -EIO;
630 	}
631 
632 	return 0;
633 }
634 
635 /*
636  * i8042_enable_aux_port enables AUX (mouse) port on chip
637  */
638 
639 static int i8042_enable_aux_port(void)
640 {
641 	i8042_ctr &= ~I8042_CTR_AUXDIS;
642 	i8042_ctr |= I8042_CTR_AUXINT;
643 
644 	if (i8042_command(&i8042_ctr, I8042_CMD_CTL_WCTR)) {
645 		i8042_ctr &= ~I8042_CTR_AUXINT;
646 		i8042_ctr |= I8042_CTR_AUXDIS;
647 		pr_err("Failed to enable AUX port\n");
648 		return -EIO;
649 	}
650 
651 	return 0;
652 }
653 
654 /*
655  * i8042_enable_mux_ports enables 4 individual AUX ports after
656  * the controller has been switched into Multiplexed mode
657  */
658 
659 static int i8042_enable_mux_ports(void)
660 {
661 	unsigned char param;
662 	int i;
663 
664 	for (i = 0; i < I8042_NUM_MUX_PORTS; i++) {
665 		i8042_command(&param, I8042_CMD_MUX_PFX + i);
666 		i8042_command(&param, I8042_CMD_AUX_ENABLE);
667 	}
668 
669 	return i8042_enable_aux_port();
670 }
671 
672 /*
673  * i8042_set_mux_mode checks whether the controller has an
674  * active multiplexor and puts the chip into Multiplexed (true)
675  * or Legacy (false) mode.
676  */
677 
678 static int i8042_set_mux_mode(bool multiplex, unsigned char *mux_version)
679 {
680 
681 	unsigned char param, val;
682 /*
683  * Get rid of bytes in the queue.
684  */
685 
686 	i8042_flush();
687 
688 /*
689  * Internal loopback test - send three bytes, they should come back from the
690  * mouse interface, the last should be version.
691  */
692 
693 	param = val = 0xf0;
694 	if (i8042_command(&param, I8042_CMD_AUX_LOOP) || param != val)
695 		return -1;
696 	param = val = multiplex ? 0x56 : 0xf6;
697 	if (i8042_command(&param, I8042_CMD_AUX_LOOP) || param != val)
698 		return -1;
699 	param = val = multiplex ? 0xa4 : 0xa5;
700 	if (i8042_command(&param, I8042_CMD_AUX_LOOP) || param == val)
701 		return -1;
702 
703 /*
704  * Workaround for interference with USB Legacy emulation
705  * that causes a v10.12 MUX to be found.
706  */
707 	if (param == 0xac)
708 		return -1;
709 
710 	if (mux_version)
711 		*mux_version = param;
712 
713 	return 0;
714 }
715 
716 /*
717  * i8042_check_mux() checks whether the controller supports the PS/2 Active
718  * Multiplexing specification by Synaptics, Phoenix, Insyde and
719  * LCS/Telegraphics.
720  */
721 
722 static int i8042_check_mux(void)
723 {
724 	unsigned char mux_version;
725 
726 	if (i8042_set_mux_mode(true, &mux_version))
727 		return -1;
728 
729 	pr_info("Detected active multiplexing controller, rev %d.%d\n",
730 		(mux_version >> 4) & 0xf, mux_version & 0xf);
731 
732 /*
733  * Disable all muxed ports by disabling AUX.
734  */
735 	i8042_ctr |= I8042_CTR_AUXDIS;
736 	i8042_ctr &= ~I8042_CTR_AUXINT;
737 
738 	if (i8042_command(&i8042_ctr, I8042_CMD_CTL_WCTR)) {
739 		pr_err("Failed to disable AUX port, can't use MUX\n");
740 		return -EIO;
741 	}
742 
743 	i8042_mux_present = true;
744 
745 	return 0;
746 }
747 
748 /*
749  * The following is used to test AUX IRQ delivery.
750  */
751 static struct completion i8042_aux_irq_delivered;
752 static bool i8042_irq_being_tested;
753 
754 static irqreturn_t i8042_aux_test_irq(int irq, void *dev_id)
755 {
756 	unsigned long flags;
757 	unsigned char str, data;
758 	int ret = 0;
759 
760 	spin_lock_irqsave(&i8042_lock, flags);
761 	str = i8042_read_status();
762 	if (str & I8042_STR_OBF) {
763 		data = i8042_read_data();
764 		dbg("%02x <- i8042 (aux_test_irq, %s)\n",
765 		    data, str & I8042_STR_AUXDATA ? "aux" : "kbd");
766 		if (i8042_irq_being_tested &&
767 		    data == 0xa5 && (str & I8042_STR_AUXDATA))
768 			complete(&i8042_aux_irq_delivered);
769 		ret = 1;
770 	}
771 	spin_unlock_irqrestore(&i8042_lock, flags);
772 
773 	return IRQ_RETVAL(ret);
774 }
775 
776 /*
777  * i8042_toggle_aux - enables or disables AUX port on i8042 via command and
778  * verifies success by readinng CTR. Used when testing for presence of AUX
779  * port.
780  */
781 static int i8042_toggle_aux(bool on)
782 {
783 	unsigned char param;
784 	int i;
785 
786 	if (i8042_command(&param,
787 			on ? I8042_CMD_AUX_ENABLE : I8042_CMD_AUX_DISABLE))
788 		return -1;
789 
790 	/* some chips need some time to set the I8042_CTR_AUXDIS bit */
791 	for (i = 0; i < 100; i++) {
792 		udelay(50);
793 
794 		if (i8042_command(&param, I8042_CMD_CTL_RCTR))
795 			return -1;
796 
797 		if (!(param & I8042_CTR_AUXDIS) == on)
798 			return 0;
799 	}
800 
801 	return -1;
802 }
803 
804 /*
805  * i8042_check_aux() applies as much paranoia as it can at detecting
806  * the presence of an AUX interface.
807  */
808 
809 static int i8042_check_aux(void)
810 {
811 	int retval = -1;
812 	bool irq_registered = false;
813 	bool aux_loop_broken = false;
814 	unsigned long flags;
815 	unsigned char param;
816 
817 /*
818  * Get rid of bytes in the queue.
819  */
820 
821 	i8042_flush();
822 
823 /*
824  * Internal loopback test - filters out AT-type i8042's. Unfortunately
825  * SiS screwed up and their 5597 doesn't support the LOOP command even
826  * though it has an AUX port.
827  */
828 
829 	param = 0x5a;
830 	retval = i8042_command(&param, I8042_CMD_AUX_LOOP);
831 	if (retval || param != 0x5a) {
832 
833 /*
834  * External connection test - filters out AT-soldered PS/2 i8042's
835  * 0x00 - no error, 0x01-0x03 - clock/data stuck, 0xff - general error
836  * 0xfa - no error on some notebooks which ignore the spec
837  * Because it's common for chipsets to return error on perfectly functioning
838  * AUX ports, we test for this only when the LOOP command failed.
839  */
840 
841 		if (i8042_command(&param, I8042_CMD_AUX_TEST) ||
842 		    (param && param != 0xfa && param != 0xff))
843 			return -1;
844 
845 /*
846  * If AUX_LOOP completed without error but returned unexpected data
847  * mark it as broken
848  */
849 		if (!retval)
850 			aux_loop_broken = true;
851 	}
852 
853 /*
854  * Bit assignment test - filters out PS/2 i8042's in AT mode
855  */
856 
857 	if (i8042_toggle_aux(false)) {
858 		pr_warn("Failed to disable AUX port, but continuing anyway... Is this a SiS?\n");
859 		pr_warn("If AUX port is really absent please use the 'i8042.noaux' option\n");
860 	}
861 
862 	if (i8042_toggle_aux(true))
863 		return -1;
864 
865 /*
866  * Reset keyboard (needed on some laptops to successfully detect
867  * touchpad, e.g., some Gigabyte laptop models with Elantech
868  * touchpads).
869  */
870 	if (i8042_kbdreset) {
871 		pr_warn("Attempting to reset device connected to KBD port\n");
872 		i8042_kbd_write(NULL, (unsigned char) 0xff);
873 	}
874 
875 /*
876  * Test AUX IRQ delivery to make sure BIOS did not grab the IRQ and
877  * used it for a PCI card or somethig else.
878  */
879 
880 	if (i8042_noloop || i8042_bypass_aux_irq_test || aux_loop_broken) {
881 /*
882  * Without LOOP command we can't test AUX IRQ delivery. Assume the port
883  * is working and hope we are right.
884  */
885 		retval = 0;
886 		goto out;
887 	}
888 
889 	if (request_irq(I8042_AUX_IRQ, i8042_aux_test_irq, IRQF_SHARED,
890 			"i8042", i8042_platform_device))
891 		goto out;
892 
893 	irq_registered = true;
894 
895 	if (i8042_enable_aux_port())
896 		goto out;
897 
898 	spin_lock_irqsave(&i8042_lock, flags);
899 
900 	init_completion(&i8042_aux_irq_delivered);
901 	i8042_irq_being_tested = true;
902 
903 	param = 0xa5;
904 	retval = __i8042_command(&param, I8042_CMD_AUX_LOOP & 0xf0ff);
905 
906 	spin_unlock_irqrestore(&i8042_lock, flags);
907 
908 	if (retval)
909 		goto out;
910 
911 	if (wait_for_completion_timeout(&i8042_aux_irq_delivered,
912 					msecs_to_jiffies(250)) == 0) {
913 /*
914  * AUX IRQ was never delivered so we need to flush the controller to
915  * get rid of the byte we put there; otherwise keyboard may not work.
916  */
917 		dbg("     -- i8042 (aux irq test timeout)\n");
918 		i8042_flush();
919 		retval = -1;
920 	}
921 
922  out:
923 
924 /*
925  * Disable the interface.
926  */
927 
928 	i8042_ctr |= I8042_CTR_AUXDIS;
929 	i8042_ctr &= ~I8042_CTR_AUXINT;
930 
931 	if (i8042_command(&i8042_ctr, I8042_CMD_CTL_WCTR))
932 		retval = -1;
933 
934 	if (irq_registered)
935 		free_irq(I8042_AUX_IRQ, i8042_platform_device);
936 
937 	return retval;
938 }
939 
940 static int i8042_controller_check(void)
941 {
942 	if (i8042_flush()) {
943 		pr_info("No controller found\n");
944 		return -ENODEV;
945 	}
946 
947 	return 0;
948 }
949 
950 static int i8042_controller_selftest(void)
951 {
952 	unsigned char param;
953 	int i = 0;
954 
955 	/*
956 	 * We try this 5 times; on some really fragile systems this does not
957 	 * take the first time...
958 	 */
959 	do {
960 
961 		if (i8042_command(&param, I8042_CMD_CTL_TEST)) {
962 			pr_err("i8042 controller selftest timeout\n");
963 			return -ENODEV;
964 		}
965 
966 		if (param == I8042_RET_CTL_TEST)
967 			return 0;
968 
969 		dbg("i8042 controller selftest: %#x != %#x\n",
970 		    param, I8042_RET_CTL_TEST);
971 		msleep(50);
972 	} while (i++ < 5);
973 
974 #ifdef CONFIG_X86
975 	/*
976 	 * On x86, we don't fail entire i8042 initialization if controller
977 	 * reset fails in hopes that keyboard port will still be functional
978 	 * and user will still get a working keyboard. This is especially
979 	 * important on netbooks. On other arches we trust hardware more.
980 	 */
981 	pr_info("giving up on controller selftest, continuing anyway...\n");
982 	return 0;
983 #else
984 	pr_err("i8042 controller selftest failed\n");
985 	return -EIO;
986 #endif
987 }
988 
989 /*
990  * i8042_controller_init initializes the i8042 controller, and,
991  * most importantly, sets it into non-xlated mode if that's
992  * desired.
993  */
994 
995 static int i8042_controller_init(void)
996 {
997 	unsigned long flags;
998 	int n = 0;
999 	unsigned char ctr[2];
1000 
1001 /*
1002  * Save the CTR for restore on unload / reboot.
1003  */
1004 
1005 	do {
1006 		if (n >= 10) {
1007 			pr_err("Unable to get stable CTR read\n");
1008 			return -EIO;
1009 		}
1010 
1011 		if (n != 0)
1012 			udelay(50);
1013 
1014 		if (i8042_command(&ctr[n++ % 2], I8042_CMD_CTL_RCTR)) {
1015 			pr_err("Can't read CTR while initializing i8042\n");
1016 			return i8042_probe_defer ? -EPROBE_DEFER : -EIO;
1017 		}
1018 
1019 	} while (n < 2 || ctr[0] != ctr[1]);
1020 
1021 	i8042_initial_ctr = i8042_ctr = ctr[0];
1022 
1023 /*
1024  * Disable the keyboard interface and interrupt.
1025  */
1026 
1027 	i8042_ctr |= I8042_CTR_KBDDIS;
1028 	i8042_ctr &= ~I8042_CTR_KBDINT;
1029 
1030 /*
1031  * Handle keylock.
1032  */
1033 
1034 	spin_lock_irqsave(&i8042_lock, flags);
1035 	if (~i8042_read_status() & I8042_STR_KEYLOCK) {
1036 		if (i8042_unlock)
1037 			i8042_ctr |= I8042_CTR_IGNKEYLOCK;
1038 		else
1039 			pr_warn("Warning: Keylock active\n");
1040 	}
1041 	spin_unlock_irqrestore(&i8042_lock, flags);
1042 
1043 /*
1044  * If the chip is configured into nontranslated mode by the BIOS, don't
1045  * bother enabling translating and be happy.
1046  */
1047 
1048 	if (~i8042_ctr & I8042_CTR_XLATE)
1049 		i8042_direct = true;
1050 
1051 /*
1052  * Set nontranslated mode for the kbd interface if requested by an option.
1053  * After this the kbd interface becomes a simple serial in/out, like the aux
1054  * interface is. We don't do this by default, since it can confuse notebook
1055  * BIOSes.
1056  */
1057 
1058 	if (i8042_direct)
1059 		i8042_ctr &= ~I8042_CTR_XLATE;
1060 
1061 /*
1062  * Write CTR back.
1063  */
1064 
1065 	if (i8042_command(&i8042_ctr, I8042_CMD_CTL_WCTR)) {
1066 		pr_err("Can't write CTR while initializing i8042\n");
1067 		return -EIO;
1068 	}
1069 
1070 /*
1071  * Flush whatever accumulated while we were disabling keyboard port.
1072  */
1073 
1074 	i8042_flush();
1075 
1076 	return 0;
1077 }
1078 
1079 
1080 /*
1081  * Reset the controller and reset CRT to the original value set by BIOS.
1082  */
1083 
1084 static void i8042_controller_reset(bool s2r_wants_reset)
1085 {
1086 	i8042_flush();
1087 
1088 /*
1089  * Disable both KBD and AUX interfaces so they don't get in the way
1090  */
1091 
1092 	i8042_ctr |= I8042_CTR_KBDDIS | I8042_CTR_AUXDIS;
1093 	i8042_ctr &= ~(I8042_CTR_KBDINT | I8042_CTR_AUXINT);
1094 
1095 	if (i8042_command(&i8042_ctr, I8042_CMD_CTL_WCTR))
1096 		pr_warn("Can't write CTR while resetting\n");
1097 
1098 /*
1099  * Disable MUX mode if present.
1100  */
1101 
1102 	if (i8042_mux_present)
1103 		i8042_set_mux_mode(false, NULL);
1104 
1105 /*
1106  * Reset the controller if requested.
1107  */
1108 
1109 	if (i8042_reset == I8042_RESET_ALWAYS ||
1110 	    (i8042_reset == I8042_RESET_ON_S2RAM && s2r_wants_reset)) {
1111 		i8042_controller_selftest();
1112 	}
1113 
1114 /*
1115  * Restore the original control register setting.
1116  */
1117 
1118 	if (i8042_command(&i8042_initial_ctr, I8042_CMD_CTL_WCTR))
1119 		pr_warn("Can't restore CTR\n");
1120 }
1121 
1122 
1123 /*
1124  * i8042_panic_blink() will turn the keyboard LEDs on or off and is called
1125  * when kernel panics. Flashing LEDs is useful for users running X who may
1126  * not see the console and will help distinguishing panics from "real"
1127  * lockups.
1128  *
1129  * Note that DELAY has a limit of 10ms so we will not get stuck here
1130  * waiting for KBC to free up even if KBD interrupt is off
1131  */
1132 
1133 #define DELAY do { mdelay(1); if (++delay > 10) return delay; } while(0)
1134 
1135 static long i8042_panic_blink(int state)
1136 {
1137 	long delay = 0;
1138 	char led;
1139 
1140 	led = (state) ? 0x01 | 0x04 : 0;
1141 	while (i8042_read_status() & I8042_STR_IBF)
1142 		DELAY;
1143 	dbg("%02x -> i8042 (panic blink)\n", 0xed);
1144 	i8042_suppress_kbd_ack = 2;
1145 	i8042_write_data(0xed); /* set leds */
1146 	DELAY;
1147 	while (i8042_read_status() & I8042_STR_IBF)
1148 		DELAY;
1149 	DELAY;
1150 	dbg("%02x -> i8042 (panic blink)\n", led);
1151 	i8042_write_data(led);
1152 	DELAY;
1153 	return delay;
1154 }
1155 
1156 #undef DELAY
1157 
1158 #ifdef CONFIG_X86
1159 static void i8042_dritek_enable(void)
1160 {
1161 	unsigned char param = 0x90;
1162 	int error;
1163 
1164 	error = i8042_command(&param, 0x1059);
1165 	if (error)
1166 		pr_warn("Failed to enable DRITEK extension: %d\n", error);
1167 }
1168 #endif
1169 
1170 #ifdef CONFIG_PM
1171 
1172 /*
1173  * Here we try to reset everything back to a state we had
1174  * before suspending.
1175  */
1176 
1177 static int i8042_controller_resume(bool s2r_wants_reset)
1178 {
1179 	int error;
1180 
1181 	error = i8042_controller_check();
1182 	if (error)
1183 		return error;
1184 
1185 	if (i8042_reset == I8042_RESET_ALWAYS ||
1186 	    (i8042_reset == I8042_RESET_ON_S2RAM && s2r_wants_reset)) {
1187 		error = i8042_controller_selftest();
1188 		if (error)
1189 			return error;
1190 	}
1191 
1192 /*
1193  * Restore original CTR value and disable all ports
1194  */
1195 
1196 	i8042_ctr = i8042_initial_ctr;
1197 	if (i8042_direct)
1198 		i8042_ctr &= ~I8042_CTR_XLATE;
1199 	i8042_ctr |= I8042_CTR_AUXDIS | I8042_CTR_KBDDIS;
1200 	i8042_ctr &= ~(I8042_CTR_AUXINT | I8042_CTR_KBDINT);
1201 	if (i8042_command(&i8042_ctr, I8042_CMD_CTL_WCTR)) {
1202 		pr_warn("Can't write CTR to resume, retrying...\n");
1203 		msleep(50);
1204 		if (i8042_command(&i8042_ctr, I8042_CMD_CTL_WCTR)) {
1205 			pr_err("CTR write retry failed\n");
1206 			return -EIO;
1207 		}
1208 	}
1209 
1210 
1211 #ifdef CONFIG_X86
1212 	if (i8042_dritek)
1213 		i8042_dritek_enable();
1214 #endif
1215 
1216 	if (i8042_mux_present) {
1217 		if (i8042_set_mux_mode(true, NULL) || i8042_enable_mux_ports())
1218 			pr_warn("failed to resume active multiplexor, mouse won't work\n");
1219 	} else if (i8042_ports[I8042_AUX_PORT_NO].serio)
1220 		i8042_enable_aux_port();
1221 
1222 	if (i8042_ports[I8042_KBD_PORT_NO].serio)
1223 		i8042_enable_kbd_port();
1224 
1225 	i8042_interrupt(0, NULL);
1226 
1227 	return 0;
1228 }
1229 
1230 /*
1231  * Here we try to restore the original BIOS settings to avoid
1232  * upsetting it.
1233  */
1234 
1235 static int i8042_pm_suspend(struct device *dev)
1236 {
1237 	int i;
1238 
1239 	if (!i8042_forcenorestore && pm_suspend_via_firmware())
1240 		i8042_controller_reset(true);
1241 
1242 	/* Set up serio interrupts for system wakeup. */
1243 	for (i = 0; i < I8042_NUM_PORTS; i++) {
1244 		struct serio *serio = i8042_ports[i].serio;
1245 
1246 		if (serio && device_may_wakeup(&serio->dev))
1247 			enable_irq_wake(i8042_ports[i].irq);
1248 	}
1249 
1250 	return 0;
1251 }
1252 
1253 static int i8042_pm_resume_noirq(struct device *dev)
1254 {
1255 	if (i8042_forcenorestore || !pm_resume_via_firmware())
1256 		i8042_interrupt(0, NULL);
1257 
1258 	return 0;
1259 }
1260 
1261 static int i8042_pm_resume(struct device *dev)
1262 {
1263 	bool want_reset;
1264 	int i;
1265 
1266 	for (i = 0; i < I8042_NUM_PORTS; i++) {
1267 		struct serio *serio = i8042_ports[i].serio;
1268 
1269 		if (serio && device_may_wakeup(&serio->dev))
1270 			disable_irq_wake(i8042_ports[i].irq);
1271 	}
1272 
1273 	/*
1274 	 * If platform firmware was not going to be involved in suspend, we did
1275 	 * not restore the controller state to whatever it had been at boot
1276 	 * time, so we do not need to do anything.
1277 	 */
1278 	if (i8042_forcenorestore || !pm_suspend_via_firmware())
1279 		return 0;
1280 
1281 	/*
1282 	 * We only need to reset the controller if we are resuming after handing
1283 	 * off control to the platform firmware, otherwise we can simply restore
1284 	 * the mode.
1285 	 */
1286 	want_reset = pm_resume_via_firmware();
1287 
1288 	return i8042_controller_resume(want_reset);
1289 }
1290 
1291 static int i8042_pm_thaw(struct device *dev)
1292 {
1293 	i8042_interrupt(0, NULL);
1294 
1295 	return 0;
1296 }
1297 
1298 static int i8042_pm_reset(struct device *dev)
1299 {
1300 	i8042_controller_reset(false);
1301 
1302 	return 0;
1303 }
1304 
1305 static int i8042_pm_restore(struct device *dev)
1306 {
1307 	return i8042_controller_resume(false);
1308 }
1309 
1310 static const struct dev_pm_ops i8042_pm_ops = {
1311 	.suspend	= i8042_pm_suspend,
1312 	.resume_noirq	= i8042_pm_resume_noirq,
1313 	.resume		= i8042_pm_resume,
1314 	.thaw		= i8042_pm_thaw,
1315 	.poweroff	= i8042_pm_reset,
1316 	.restore	= i8042_pm_restore,
1317 };
1318 
1319 #endif /* CONFIG_PM */
1320 
1321 /*
1322  * We need to reset the 8042 back to original mode on system shutdown,
1323  * because otherwise BIOSes will be confused.
1324  */
1325 
1326 static void i8042_shutdown(struct platform_device *dev)
1327 {
1328 	i8042_controller_reset(false);
1329 }
1330 
1331 static int i8042_create_kbd_port(void)
1332 {
1333 	struct serio *serio;
1334 	struct i8042_port *port = &i8042_ports[I8042_KBD_PORT_NO];
1335 
1336 	serio = kzalloc(sizeof(*serio), GFP_KERNEL);
1337 	if (!serio)
1338 		return -ENOMEM;
1339 
1340 	serio->id.type		= i8042_direct ? SERIO_8042 : SERIO_8042_XL;
1341 	serio->write		= i8042_dumbkbd ? NULL : i8042_kbd_write;
1342 	serio->start		= i8042_start;
1343 	serio->stop		= i8042_stop;
1344 	serio->close		= i8042_port_close;
1345 	serio->ps2_cmd_mutex	= &i8042_mutex;
1346 	serio->port_data	= port;
1347 	serio->dev.parent	= &i8042_platform_device->dev;
1348 	strscpy(serio->name, "i8042 KBD port", sizeof(serio->name));
1349 	strscpy(serio->phys, I8042_KBD_PHYS_DESC, sizeof(serio->phys));
1350 	strscpy(serio->firmware_id, i8042_kbd_firmware_id,
1351 		sizeof(serio->firmware_id));
1352 	set_primary_fwnode(&serio->dev, i8042_kbd_fwnode);
1353 
1354 	port->serio = serio;
1355 	port->irq = I8042_KBD_IRQ;
1356 
1357 	return 0;
1358 }
1359 
1360 static int i8042_create_aux_port(int idx)
1361 {
1362 	struct serio *serio;
1363 	int port_no = idx < 0 ? I8042_AUX_PORT_NO : I8042_MUX_PORT_NO + idx;
1364 	struct i8042_port *port = &i8042_ports[port_no];
1365 
1366 	serio = kzalloc(sizeof(*serio), GFP_KERNEL);
1367 	if (!serio)
1368 		return -ENOMEM;
1369 
1370 	serio->id.type		= SERIO_8042;
1371 	serio->write		= i8042_aux_write;
1372 	serio->start		= i8042_start;
1373 	serio->stop		= i8042_stop;
1374 	serio->ps2_cmd_mutex	= &i8042_mutex;
1375 	serio->port_data	= port;
1376 	serio->dev.parent	= &i8042_platform_device->dev;
1377 	if (idx < 0) {
1378 		strscpy(serio->name, "i8042 AUX port", sizeof(serio->name));
1379 		strscpy(serio->phys, I8042_AUX_PHYS_DESC, sizeof(serio->phys));
1380 		strscpy(serio->firmware_id, i8042_aux_firmware_id,
1381 			sizeof(serio->firmware_id));
1382 		serio->close = i8042_port_close;
1383 	} else {
1384 		snprintf(serio->name, sizeof(serio->name), "i8042 AUX%d port", idx);
1385 		snprintf(serio->phys, sizeof(serio->phys), I8042_MUX_PHYS_DESC, idx + 1);
1386 		strscpy(serio->firmware_id, i8042_aux_firmware_id,
1387 			sizeof(serio->firmware_id));
1388 	}
1389 
1390 	port->serio = serio;
1391 	port->mux = idx;
1392 	port->irq = I8042_AUX_IRQ;
1393 
1394 	return 0;
1395 }
1396 
1397 static void i8042_free_kbd_port(void)
1398 {
1399 	kfree(i8042_ports[I8042_KBD_PORT_NO].serio);
1400 	i8042_ports[I8042_KBD_PORT_NO].serio = NULL;
1401 }
1402 
1403 static void i8042_free_aux_ports(void)
1404 {
1405 	int i;
1406 
1407 	for (i = I8042_AUX_PORT_NO; i < I8042_NUM_PORTS; i++) {
1408 		kfree(i8042_ports[i].serio);
1409 		i8042_ports[i].serio = NULL;
1410 	}
1411 }
1412 
1413 static void i8042_register_ports(void)
1414 {
1415 	int i;
1416 
1417 	for (i = 0; i < I8042_NUM_PORTS; i++) {
1418 		struct serio *serio = i8042_ports[i].serio;
1419 
1420 		if (!serio)
1421 			continue;
1422 
1423 		printk(KERN_INFO "serio: %s at %#lx,%#lx irq %d\n",
1424 			serio->name,
1425 			(unsigned long) I8042_DATA_REG,
1426 			(unsigned long) I8042_COMMAND_REG,
1427 			i8042_ports[i].irq);
1428 		serio_register_port(serio);
1429 	}
1430 }
1431 
1432 static void i8042_unregister_ports(void)
1433 {
1434 	int i;
1435 
1436 	for (i = 0; i < I8042_NUM_PORTS; i++) {
1437 		if (i8042_ports[i].serio) {
1438 			serio_unregister_port(i8042_ports[i].serio);
1439 			i8042_ports[i].serio = NULL;
1440 		}
1441 	}
1442 }
1443 
1444 static void i8042_free_irqs(void)
1445 {
1446 	if (i8042_aux_irq_registered)
1447 		free_irq(I8042_AUX_IRQ, i8042_platform_device);
1448 	if (i8042_kbd_irq_registered)
1449 		free_irq(I8042_KBD_IRQ, i8042_platform_device);
1450 
1451 	i8042_aux_irq_registered = i8042_kbd_irq_registered = false;
1452 }
1453 
1454 static int i8042_setup_aux(void)
1455 {
1456 	int (*aux_enable)(void);
1457 	int error;
1458 	int i;
1459 
1460 	if (i8042_check_aux())
1461 		return -ENODEV;
1462 
1463 	if (i8042_nomux || i8042_check_mux()) {
1464 		error = i8042_create_aux_port(-1);
1465 		if (error)
1466 			goto err_free_ports;
1467 		aux_enable = i8042_enable_aux_port;
1468 	} else {
1469 		for (i = 0; i < I8042_NUM_MUX_PORTS; i++) {
1470 			error = i8042_create_aux_port(i);
1471 			if (error)
1472 				goto err_free_ports;
1473 		}
1474 		aux_enable = i8042_enable_mux_ports;
1475 	}
1476 
1477 	error = request_irq(I8042_AUX_IRQ, i8042_interrupt, IRQF_SHARED,
1478 			    "i8042", i8042_platform_device);
1479 	if (error)
1480 		goto err_free_ports;
1481 
1482 	error = aux_enable();
1483 	if (error)
1484 		goto err_free_irq;
1485 
1486 	i8042_aux_irq_registered = true;
1487 	return 0;
1488 
1489  err_free_irq:
1490 	free_irq(I8042_AUX_IRQ, i8042_platform_device);
1491  err_free_ports:
1492 	i8042_free_aux_ports();
1493 	return error;
1494 }
1495 
1496 static int i8042_setup_kbd(void)
1497 {
1498 	int error;
1499 
1500 	error = i8042_create_kbd_port();
1501 	if (error)
1502 		return error;
1503 
1504 	error = request_irq(I8042_KBD_IRQ, i8042_interrupt, IRQF_SHARED,
1505 			    "i8042", i8042_platform_device);
1506 	if (error)
1507 		goto err_free_port;
1508 
1509 	error = i8042_enable_kbd_port();
1510 	if (error)
1511 		goto err_free_irq;
1512 
1513 	i8042_kbd_irq_registered = true;
1514 	return 0;
1515 
1516  err_free_irq:
1517 	free_irq(I8042_KBD_IRQ, i8042_platform_device);
1518  err_free_port:
1519 	i8042_free_kbd_port();
1520 	return error;
1521 }
1522 
1523 static int i8042_kbd_bind_notifier(struct notifier_block *nb,
1524 				   unsigned long action, void *data)
1525 {
1526 	struct device *dev = data;
1527 	struct serio *serio = to_serio_port(dev);
1528 	struct i8042_port *port = serio->port_data;
1529 
1530 	if (serio != i8042_ports[I8042_KBD_PORT_NO].serio)
1531 		return 0;
1532 
1533 	switch (action) {
1534 	case BUS_NOTIFY_BOUND_DRIVER:
1535 		port->driver_bound = true;
1536 		break;
1537 
1538 	case BUS_NOTIFY_UNBIND_DRIVER:
1539 		port->driver_bound = false;
1540 		break;
1541 	}
1542 
1543 	return 0;
1544 }
1545 
1546 static int i8042_probe(struct platform_device *dev)
1547 {
1548 	int error;
1549 
1550 	if (i8042_reset == I8042_RESET_ALWAYS) {
1551 		error = i8042_controller_selftest();
1552 		if (error)
1553 			return error;
1554 	}
1555 
1556 	error = i8042_controller_init();
1557 	if (error)
1558 		return error;
1559 
1560 #ifdef CONFIG_X86
1561 	if (i8042_dritek)
1562 		i8042_dritek_enable();
1563 #endif
1564 
1565 	if (!i8042_noaux) {
1566 		error = i8042_setup_aux();
1567 		if (error && error != -ENODEV && error != -EBUSY)
1568 			goto out_fail;
1569 	}
1570 
1571 	if (!i8042_nokbd) {
1572 		error = i8042_setup_kbd();
1573 		if (error)
1574 			goto out_fail;
1575 	}
1576 /*
1577  * Ok, everything is ready, let's register all serio ports
1578  */
1579 	i8042_register_ports();
1580 
1581 	return 0;
1582 
1583  out_fail:
1584 	i8042_free_aux_ports();	/* in case KBD failed but AUX not */
1585 	i8042_free_irqs();
1586 	i8042_controller_reset(false);
1587 
1588 	return error;
1589 }
1590 
1591 static void i8042_remove(struct platform_device *dev)
1592 {
1593 	i8042_unregister_ports();
1594 	i8042_free_irqs();
1595 	i8042_controller_reset(false);
1596 }
1597 
1598 static struct platform_driver i8042_driver = {
1599 	.driver		= {
1600 		.name	= "i8042",
1601 #ifdef CONFIG_PM
1602 		.pm	= &i8042_pm_ops,
1603 #endif
1604 	},
1605 	.probe		= i8042_probe,
1606 	.remove_new	= i8042_remove,
1607 	.shutdown	= i8042_shutdown,
1608 };
1609 
1610 static struct notifier_block i8042_kbd_bind_notifier_block = {
1611 	.notifier_call = i8042_kbd_bind_notifier,
1612 };
1613 
1614 static int __init i8042_init(void)
1615 {
1616 	int err;
1617 
1618 	dbg_init();
1619 
1620 	err = i8042_platform_init();
1621 	if (err)
1622 		return (err == -ENODEV) ? 0 : err;
1623 
1624 	err = i8042_controller_check();
1625 	if (err)
1626 		goto err_platform_exit;
1627 
1628 	/* Set this before creating the dev to allow i8042_command to work right away */
1629 	i8042_present = true;
1630 
1631 	err = platform_driver_register(&i8042_driver);
1632 	if (err)
1633 		goto err_platform_exit;
1634 
1635 	i8042_platform_device = platform_device_alloc("i8042", -1);
1636 	if (!i8042_platform_device) {
1637 		err = -ENOMEM;
1638 		goto err_unregister_driver;
1639 	}
1640 
1641 	err = platform_device_add(i8042_platform_device);
1642 	if (err)
1643 		goto err_free_device;
1644 
1645 	bus_register_notifier(&serio_bus, &i8042_kbd_bind_notifier_block);
1646 	panic_blink = i8042_panic_blink;
1647 
1648 	return 0;
1649 
1650 err_free_device:
1651 	platform_device_put(i8042_platform_device);
1652 err_unregister_driver:
1653 	platform_driver_unregister(&i8042_driver);
1654  err_platform_exit:
1655 	i8042_platform_exit();
1656 	return err;
1657 }
1658 
1659 static void __exit i8042_exit(void)
1660 {
1661 	if (!i8042_present)
1662 		return;
1663 
1664 	platform_device_unregister(i8042_platform_device);
1665 	platform_driver_unregister(&i8042_driver);
1666 	i8042_platform_exit();
1667 
1668 	bus_unregister_notifier(&serio_bus, &i8042_kbd_bind_notifier_block);
1669 	panic_blink = NULL;
1670 }
1671 
1672 module_init(i8042_init);
1673 module_exit(i8042_exit);
1674