xref: /freebsd/sys/dev/ichiic/ig4_iic.c (revision edf8578117e8844e02c0121147f45e4609b30680)
1 /*
2  * Copyright (c) 2014 The DragonFly Project.  All rights reserved.
3  *
4  * This code is derived from software contributed to The DragonFly Project
5  * by Matthew Dillon <dillon@backplane.com> and was subsequently ported
6  * to FreeBSD by Michael Gmelin <freebsd@grem.de>
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in
16  *    the documentation and/or other materials provided with the
17  *    distribution.
18  * 3. Neither the name of The DragonFly Project nor the names of its
19  *    contributors may be used to endorse or promote products derived
20  *    from this software without specific, prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
25  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
26  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
27  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
28  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
29  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
30  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
31  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
32  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/cdefs.h>
37 /*
38  * Intel fourth generation mobile cpus integrated I2C device.
39  *
40  * See ig4_reg.h for datasheet reference and notes.
41  * See ig4_var.h for locking semantics.
42  */
43 
44 #include "opt_acpi.h"
45 
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/kernel.h>
49 #include <sys/module.h>
50 #include <sys/errno.h>
51 #include <sys/kdb.h>
52 #include <sys/lock.h>
53 #include <sys/mutex.h>
54 #include <sys/proc.h>
55 #include <sys/sx.h>
56 #include <sys/syslog.h>
57 #include <sys/bus.h>
58 #include <sys/sysctl.h>
59 
60 #include <machine/bus.h>
61 #include <sys/rman.h>
62 
63 #ifdef DEV_ACPI
64 #include <contrib/dev/acpica/include/acpi.h>
65 #include <contrib/dev/acpica/include/accommon.h>
66 #include <dev/acpica/acpivar.h>
67 #endif
68 
69 #include <dev/iicbus/iicbus.h>
70 #include <dev/iicbus/iiconf.h>
71 
72 #include <dev/ichiic/ig4_reg.h>
73 #include <dev/ichiic/ig4_var.h>
74 
75 #define DO_POLL(sc)	(cold || kdb_active || SCHEDULER_STOPPED() || sc->poll)
76 
77 /*
78  * tLOW, tHIGH periods of the SCL clock and maximal falling time of both
79  * lines are taken from I2C specifications.
80  */
81 #define	IG4_SPEED_STD_THIGH	4000	/* nsec */
82 #define	IG4_SPEED_STD_TLOW	4700	/* nsec */
83 #define	IG4_SPEED_STD_TF_MAX	300	/* nsec */
84 #define	IG4_SPEED_FAST_THIGH	600	/* nsec */
85 #define	IG4_SPEED_FAST_TLOW	1300	/* nsec */
86 #define	IG4_SPEED_FAST_TF_MAX	300	/* nsec */
87 
88 /*
89  * Ig4 hardware parameters except Haswell are taken from intel_lpss driver
90  */
91 static const struct ig4_hw ig4iic_hw[] = {
92 	[IG4_HASWELL] = {
93 		.ic_clock_rate = 100,	/* MHz */
94 		.sda_hold_time = 90,	/* nsec */
95 		.txfifo_depth = 32,
96 		.rxfifo_depth = 32,
97 	},
98 	[IG4_ATOM] = {
99 		.ic_clock_rate = 100,
100 		.sda_fall_time = 280,
101 		.scl_fall_time = 240,
102 		.sda_hold_time = 60,
103 		.txfifo_depth = 32,
104 		.rxfifo_depth = 32,
105 	},
106 	[IG4_SKYLAKE] = {
107 		.ic_clock_rate = 120,
108 		.sda_hold_time = 230,
109 	},
110 	[IG4_APL] = {
111 		.ic_clock_rate = 133,
112 		.sda_fall_time = 171,
113 		.scl_fall_time = 208,
114 		.sda_hold_time = 207,
115 	},
116 	[IG4_CANNONLAKE] = {
117 		.ic_clock_rate = 216,
118 		.sda_hold_time = 230,
119 	},
120 	[IG4_TIGERLAKE] = {
121 		.ic_clock_rate = 133,
122 		.sda_fall_time = 171,
123 		.scl_fall_time = 208,
124 		.sda_hold_time = 42,
125 	},
126 	[IG4_GEMINILAKE] = {
127 		.ic_clock_rate = 133,
128 		.sda_fall_time = 171,
129 		.scl_fall_time = 290,
130 		.sda_hold_time = 313,
131 	},
132 };
133 
134 static int ig4iic_set_config(ig4iic_softc_t *sc, bool reset);
135 static driver_filter_t ig4iic_intr;
136 static void ig4iic_dump(ig4iic_softc_t *sc);
137 
138 static int ig4_dump;
139 SYSCTL_INT(_debug, OID_AUTO, ig4_dump, CTLFLAG_RW,
140 	   &ig4_dump, 0, "Dump controller registers");
141 
142 /*
143  * Clock registers initialization control
144  * 0 - Try read clock registers from ACPI and fallback to p.1.
145  * 1 - Calculate values based on controller type (IC clock rate).
146  * 2 - Use values inherited from DragonflyBSD driver (old behavior).
147  * 3 - Keep clock registers intact.
148  */
149 static int ig4_timings;
150 SYSCTL_INT(_debug, OID_AUTO, ig4_timings, CTLFLAG_RDTUN, &ig4_timings, 0,
151     "Controller timings 0=ACPI, 1=predefined, 2=legacy, 3=do not change");
152 
153 /*
154  * Low-level inline support functions
155  */
156 static __inline void
157 reg_write(ig4iic_softc_t *sc, uint32_t reg, uint32_t value)
158 {
159 	bus_write_4(sc->regs_res, reg, value);
160 	bus_barrier(sc->regs_res, reg, 4, BUS_SPACE_BARRIER_WRITE);
161 }
162 
163 static __inline uint32_t
164 reg_read(ig4iic_softc_t *sc, uint32_t reg)
165 {
166 	uint32_t value;
167 
168 	bus_barrier(sc->regs_res, reg, 4, BUS_SPACE_BARRIER_READ);
169 	value = bus_read_4(sc->regs_res, reg);
170 	return (value);
171 }
172 
173 static void
174 ig4iic_set_intr_mask(ig4iic_softc_t *sc, uint32_t val)
175 {
176 	if (sc->intr_mask != val) {
177 		reg_write(sc, IG4_REG_INTR_MASK, val);
178 		sc->intr_mask = val;
179 	}
180 }
181 
182 static int
183 intrstat2iic(ig4iic_softc_t *sc, uint32_t val)
184 {
185 	uint32_t src;
186 
187 	if (val & IG4_INTR_RX_UNDER)
188 		reg_read(sc, IG4_REG_CLR_RX_UNDER);
189 	if (val & IG4_INTR_RX_OVER)
190 		reg_read(sc, IG4_REG_CLR_RX_OVER);
191 	if (val & IG4_INTR_TX_OVER)
192 		reg_read(sc, IG4_REG_CLR_TX_OVER);
193 
194 	if (val & IG4_INTR_TX_ABRT) {
195 		src = reg_read(sc, IG4_REG_TX_ABRT_SOURCE);
196 		reg_read(sc, IG4_REG_CLR_TX_ABORT);
197 		/* User-requested abort. Not really a error */
198 		if (src & IG4_ABRTSRC_TRANSFER)
199 			return (IIC_ESTATUS);
200 		/* Master has lost arbitration */
201 		if (src & IG4_ABRTSRC_ARBLOST)
202 			return (IIC_EBUSBSY);
203 		/* Did not receive an acknowledge from the remote slave */
204 		if (src & (IG4_ABRTSRC_TXNOACK_ADDR7 |
205 			   IG4_ABRTSRC_TXNOACK_ADDR10_1 |
206 			   IG4_ABRTSRC_TXNOACK_ADDR10_2 |
207 			   IG4_ABRTSRC_TXNOACK_DATA |
208 			   IG4_ABRTSRC_GENCALL_NOACK))
209 			return (IIC_ENOACK);
210 		/* Programming errors */
211 		if (src & (IG4_ABRTSRC_GENCALL_READ |
212 			   IG4_ABRTSRC_NORESTART_START |
213 			   IG4_ABRTSRC_NORESTART_10))
214 			return (IIC_ENOTSUPP);
215 		/* Other errors */
216 		if (src & IG4_ABRTSRC_ACKED_START)
217 			return (IIC_EBUSERR);
218 	}
219 	/*
220 	 * TX_OVER, RX_OVER and RX_UNDER are caused by wrong RX/TX FIFO depth
221 	 * detection or driver's read/write pipelining errors.
222 	 */
223 	if (val & (IG4_INTR_TX_OVER | IG4_INTR_RX_OVER))
224 		return (IIC_EOVERFLOW);
225 	if (val & IG4_INTR_RX_UNDER)
226 		return (IIC_EUNDERFLOW);
227 
228 	return (IIC_NOERR);
229 }
230 
231 /*
232  * Enable or disable the controller and wait for the controller to acknowledge
233  * the state change.
234  */
235 static int
236 set_controller(ig4iic_softc_t *sc, uint32_t ctl)
237 {
238 	int retry;
239 	int error;
240 	uint32_t v;
241 
242 	/*
243 	 * When the controller is enabled, interrupt on STOP detect
244 	 * or receive character ready and clear pending interrupts.
245 	 */
246 	ig4iic_set_intr_mask(sc, 0);
247 	if (ctl & IG4_I2C_ENABLE)
248 		reg_read(sc, IG4_REG_CLR_INTR);
249 
250 	reg_write(sc, IG4_REG_I2C_EN, ctl);
251 	error = IIC_ETIMEOUT;
252 
253 	for (retry = 100; retry > 0; --retry) {
254 		v = reg_read(sc, IG4_REG_ENABLE_STATUS);
255 		if (((v ^ ctl) & IG4_I2C_ENABLE) == 0) {
256 			error = 0;
257 			break;
258 		}
259 		pause("i2cslv", 1);
260 	}
261 	return (error);
262 }
263 
264 /*
265  * Wait up to 25ms for the requested interrupt using a 25uS polling loop.
266  */
267 static int
268 wait_intr(ig4iic_softc_t *sc, uint32_t intr)
269 {
270 	uint32_t v;
271 	int error;
272 	int txlvl = -1;
273 	u_int count_us = 0;
274 	u_int limit_us = 1000000; /* 1sec */
275 
276 	for (;;) {
277 		/*
278 		 * Check requested status
279 		 */
280 		v = reg_read(sc, IG4_REG_RAW_INTR_STAT);
281 		error = intrstat2iic(sc, v & IG4_INTR_ERR_MASK);
282 		if (error || (v & intr))
283 			break;
284 
285 		/*
286 		 * When waiting for the transmit FIFO to become empty,
287 		 * reset the timeout if we see a change in the transmit
288 		 * FIFO level as progress is being made.
289 		 */
290 		if (intr & (IG4_INTR_TX_EMPTY | IG4_INTR_STOP_DET)) {
291 			v = reg_read(sc, IG4_REG_TXFLR) & IG4_FIFOLVL_MASK;
292 			if (txlvl != v) {
293 				txlvl = v;
294 				count_us = 0;
295 			}
296 		}
297 
298 		/*
299 		 * Stop if we've run out of time.
300 		 */
301 		if (count_us >= limit_us) {
302 			error = IIC_ETIMEOUT;
303 			break;
304 		}
305 
306 		/*
307 		 * When polling is not requested let the interrupt do its work.
308 		 */
309 		if (!DO_POLL(sc)) {
310 			mtx_lock_spin(&sc->io_lock);
311 			ig4iic_set_intr_mask(sc, intr | IG4_INTR_ERR_MASK);
312 			msleep_spin(sc, &sc->io_lock, "i2cwait",
313 				  (hz + 99) / 100); /* sleep up to 10ms */
314 			ig4iic_set_intr_mask(sc, 0);
315 			mtx_unlock_spin(&sc->io_lock);
316 			count_us += 10000;
317 		} else {
318 			DELAY(25);
319 			count_us += 25;
320 		}
321 	}
322 
323 	return (error);
324 }
325 
326 /*
327  * Set the slave address.  The controller must be disabled when
328  * changing the address.
329  *
330  * This operation does not issue anything to the I2C bus but sets
331  * the target address for when the controller later issues a START.
332  */
333 static void
334 set_slave_addr(ig4iic_softc_t *sc, uint8_t slave)
335 {
336 	uint32_t tar;
337 	uint32_t ctl;
338 	bool use_10bit;
339 
340 	use_10bit = false;
341 	if (sc->slave_valid && sc->last_slave == slave &&
342 	    sc->use_10bit == use_10bit) {
343 		return;
344 	}
345 	sc->use_10bit = use_10bit;
346 
347 	/*
348 	 * Wait for TXFIFO to drain before disabling the controller.
349 	 */
350 	wait_intr(sc, IG4_INTR_TX_EMPTY);
351 
352 	set_controller(sc, 0);
353 	ctl = reg_read(sc, IG4_REG_CTL);
354 	ctl &= ~IG4_CTL_10BIT;
355 	ctl |= IG4_CTL_RESTARTEN;
356 
357 	tar = slave;
358 	if (sc->use_10bit) {
359 		tar |= IG4_TAR_10BIT;
360 		ctl |= IG4_CTL_10BIT;
361 	}
362 	reg_write(sc, IG4_REG_CTL, ctl);
363 	reg_write(sc, IG4_REG_TAR_ADD, tar);
364 	set_controller(sc, IG4_I2C_ENABLE);
365 	sc->slave_valid = true;
366 	sc->last_slave = slave;
367 }
368 
369 /*
370  *				IICBUS API FUNCTIONS
371  */
372 static int
373 ig4iic_xfer_start(ig4iic_softc_t *sc, uint16_t slave, bool repeated_start)
374 {
375 	set_slave_addr(sc, slave >> 1);
376 
377 	if (!repeated_start) {
378 		/*
379 		 * Clear any previous TX/RX FIFOs overflow/underflow bits
380 		 * and I2C bus STOP condition.
381 		 */
382 		reg_read(sc, IG4_REG_CLR_INTR);
383 	}
384 
385 	return (0);
386 }
387 
388 static bool
389 ig4iic_xfer_is_started(ig4iic_softc_t *sc)
390 {
391 	/*
392 	 * It requires that no IG4_REG_CLR_INTR or IG4_REG_CLR_START/STOP_DET
393 	 * register reads is issued after START condition.
394 	 */
395 	return ((reg_read(sc, IG4_REG_RAW_INTR_STAT) &
396 	    (IG4_INTR_START_DET | IG4_INTR_STOP_DET)) == IG4_INTR_START_DET);
397 }
398 
399 static int
400 ig4iic_xfer_abort(ig4iic_softc_t *sc)
401 {
402 	int error;
403 
404 	/* Request send of STOP condition and flush of TX FIFO */
405 	set_controller(sc, IG4_I2C_ABORT | IG4_I2C_ENABLE);
406 	/*
407 	 * Wait for the TX_ABRT interrupt with ABRTSRC_TRANSFER
408 	 * bit set in TX_ABRT_SOURCE register.
409 	 */
410 	error = wait_intr(sc, IG4_INTR_STOP_DET);
411 	set_controller(sc, IG4_I2C_ENABLE);
412 
413 	return (error == IIC_ESTATUS ? 0 : error);
414 }
415 
416 /*
417  * Amount of unread data before next burst to get better I2C bus utilization.
418  * 2 bytes is enough in FAST mode. 8 bytes is better in FAST+ and HIGH modes.
419  * Intel-recommended value is 16 for DMA transfers with 64-byte depth FIFOs.
420  */
421 #define	IG4_FIFO_LOWAT	2
422 
423 static int
424 ig4iic_read(ig4iic_softc_t *sc, uint8_t *buf, uint16_t len,
425     bool repeated_start, bool stop)
426 {
427 	uint32_t cmd;
428 	int requested = 0;
429 	int received = 0;
430 	int burst, target, lowat = 0;
431 	int error;
432 
433 	if (len == 0)
434 		return (0);
435 
436 	while (received < len) {
437 		burst = sc->cfg.txfifo_depth -
438 		    (reg_read(sc, IG4_REG_TXFLR) & IG4_FIFOLVL_MASK);
439 		if (burst <= 0) {
440 			error = wait_intr(sc, IG4_INTR_TX_EMPTY);
441 			if (error)
442 				break;
443 			burst = sc->cfg.txfifo_depth;
444 		}
445 		/* Ensure we have enough free space in RXFIFO */
446 		burst = MIN(burst, sc->cfg.rxfifo_depth - lowat);
447 		target = MIN(requested + burst, (int)len);
448 		while (requested < target) {
449 			cmd = IG4_DATA_COMMAND_RD;
450 			if (repeated_start && requested == 0)
451 				cmd |= IG4_DATA_RESTART;
452 			if (stop && requested == len - 1)
453 				cmd |= IG4_DATA_STOP;
454 			reg_write(sc, IG4_REG_DATA_CMD, cmd);
455 			requested++;
456 		}
457 		/* Leave some data queued to maintain the hardware pipeline */
458 		lowat = 0;
459 		if (requested != len && requested - received > IG4_FIFO_LOWAT)
460 			lowat = IG4_FIFO_LOWAT;
461 		/* After TXFLR fills up, clear it by reading available data */
462 		while (received < requested - lowat) {
463 			burst = MIN((int)len - received,
464 			    reg_read(sc, IG4_REG_RXFLR) & IG4_FIFOLVL_MASK);
465 			if (burst > 0) {
466 				while (burst--)
467 					buf[received++] = 0xFF &
468 					    reg_read(sc, IG4_REG_DATA_CMD);
469 			} else {
470 				error = wait_intr(sc, IG4_INTR_RX_FULL);
471 				if (error)
472 					goto out;
473 			}
474 		}
475 	}
476 out:
477 	return (error);
478 }
479 
480 static int
481 ig4iic_write(ig4iic_softc_t *sc, uint8_t *buf, uint16_t len,
482     bool repeated_start, bool stop)
483 {
484 	uint32_t cmd;
485 	int sent = 0;
486 	int burst, target;
487 	int error;
488 	bool lowat_set = false;
489 
490 	if (len == 0)
491 		return (0);
492 
493 	while (sent < len) {
494 		burst = sc->cfg.txfifo_depth -
495 		    (reg_read(sc, IG4_REG_TXFLR) & IG4_FIFOLVL_MASK);
496 		target = MIN(sent + burst, (int)len);
497 		/* Leave some data queued to maintain the hardware pipeline */
498 		if (!lowat_set && target != len) {
499 			lowat_set = true;
500 			reg_write(sc, IG4_REG_TX_TL, IG4_FIFO_LOWAT);
501 		}
502 		while(sent < target) {
503 			cmd = buf[sent];
504 			if (repeated_start && sent == 0)
505 				cmd |= IG4_DATA_RESTART;
506 			if (stop && sent == len - 1)
507 				cmd |= IG4_DATA_STOP;
508 			reg_write(sc, IG4_REG_DATA_CMD, cmd);
509 			sent++;
510 		}
511 		if (sent < len) {
512 			error = wait_intr(sc, IG4_INTR_TX_EMPTY);
513 			if (error)
514 				break;
515 		}
516 	}
517 	if (lowat_set)
518 		reg_write(sc, IG4_REG_TX_TL, 0);
519 
520 	return (error);
521 }
522 
523 int
524 ig4iic_transfer(device_t dev, struct iic_msg *msgs, uint32_t nmsgs)
525 {
526 	ig4iic_softc_t *sc = device_get_softc(dev);
527 	const char *reason = NULL;
528 	uint32_t i;
529 	int error;
530 	int unit;
531 	bool rpstart;
532 	bool stop;
533 	bool allocated;
534 
535 	/*
536 	 * The hardware interface imposes limits on allowed I2C messages.
537 	 * It is not possible to explicitly send a start or stop.
538 	 * They are automatically sent (or not sent, depending on the
539 	 * configuration) when a data byte is transferred.
540 	 * For this reason it's impossible to send a message with no data
541 	 * at all (like an SMBus quick message).
542 	 * The start condition is automatically generated after the stop
543 	 * condition, so it's impossible to not have a start after a stop.
544 	 * The repeated start condition is automatically sent if a change
545 	 * of the transfer direction happens, so it's impossible to have
546 	 * a change of direction without a (repeated) start.
547 	 * The repeated start can be forced even without the change of
548 	 * direction.
549 	 * Changing the target slave address requires resetting the hardware
550 	 * state, so it's impossible to do that without the stop followed
551 	 * by the start.
552 	 */
553 	for (i = 0; i < nmsgs; i++) {
554 #if 0
555 		if (i == 0 && (msgs[i].flags & IIC_M_NOSTART) != 0) {
556 			reason = "first message without start";
557 			break;
558 		}
559 		if (i == nmsgs - 1 && (msgs[i].flags & IIC_M_NOSTOP) != 0) {
560 			reason = "last message without stop";
561 			break;
562 		}
563 #endif
564 		if (msgs[i].len == 0) {
565 			reason = "message with no data";
566 			break;
567 		}
568 		if (i > 0) {
569 			if ((msgs[i].flags & IIC_M_NOSTART) != 0 &&
570 			    (msgs[i - 1].flags & IIC_M_NOSTOP) == 0) {
571 				reason = "stop not followed by start";
572 				break;
573 			}
574 			if ((msgs[i - 1].flags & IIC_M_NOSTOP) != 0 &&
575 			    msgs[i].slave != msgs[i - 1].slave) {
576 				reason = "change of slave without stop";
577 				break;
578 			}
579 			if ((msgs[i].flags & IIC_M_NOSTART) != 0 &&
580 			    (msgs[i].flags & IIC_M_RD) !=
581 			    (msgs[i - 1].flags & IIC_M_RD)) {
582 				reason = "change of direction without repeated"
583 				    " start";
584 				break;
585 			}
586 		}
587 	}
588 	if (reason != NULL) {
589 		if (bootverbose)
590 			device_printf(dev, "%s\n", reason);
591 		return (IIC_ENOTSUPP);
592 	}
593 
594 	/* Check if device is already allocated with iicbus_request_bus() */
595 	allocated = sx_xlocked(&sc->call_lock) != 0;
596 	if (!allocated)
597 		sx_xlock(&sc->call_lock);
598 
599 	/* Debugging - dump registers. */
600 	if (ig4_dump) {
601 		unit = device_get_unit(dev);
602 		if (ig4_dump & (1 << unit)) {
603 			ig4_dump &= ~(1 << unit);
604 			ig4iic_dump(sc);
605 		}
606 	}
607 
608 	/*
609 	 * Clear any previous abort condition that may have been holding
610 	 * the txfifo in reset.
611 	 */
612 	reg_read(sc, IG4_REG_CLR_TX_ABORT);
613 
614 	rpstart = false;
615 	error = 0;
616 	for (i = 0; i < nmsgs; i++) {
617 		if ((msgs[i].flags & IIC_M_NOSTART) == 0) {
618 			error = ig4iic_xfer_start(sc, msgs[i].slave, rpstart);
619 		} else {
620 			if (!sc->slave_valid ||
621 			    (msgs[i].slave >> 1) != sc->last_slave) {
622 				device_printf(dev, "start condition suppressed"
623 				    "but slave address is not set up");
624 				error = EINVAL;
625 				break;
626 			}
627 			rpstart = false;
628 		}
629 		if (error != 0)
630 			break;
631 
632 		stop = (msgs[i].flags & IIC_M_NOSTOP) == 0;
633 		if (msgs[i].flags & IIC_M_RD)
634 			error = ig4iic_read(sc, msgs[i].buf, msgs[i].len,
635 			    rpstart, stop);
636 		else
637 			error = ig4iic_write(sc, msgs[i].buf, msgs[i].len,
638 			    rpstart, stop);
639 
640 		/* Wait for error or stop condition occurred on the I2C bus */
641 		if (stop && error == 0) {
642 			error = wait_intr(sc, IG4_INTR_STOP_DET);
643 			if (error == 0)
644 				reg_read(sc, IG4_REG_CLR_INTR);
645 		}
646 
647 		if (error != 0) {
648 			/*
649 			 * Send STOP condition if it's not done yet and flush
650 			 * both FIFOs. Do a controller soft reset if transfer
651 			 * abort is failed.
652 			 */
653 			if (ig4iic_xfer_is_started(sc) &&
654 			    ig4iic_xfer_abort(sc) != 0) {
655 				device_printf(sc->dev, "Failed to abort "
656 				    "transfer. Do the controller reset.\n");
657 				ig4iic_set_config(sc, true);
658 			} else {
659 				while (reg_read(sc, IG4_REG_I2C_STA) &
660 				    IG4_STATUS_RX_NOTEMPTY)
661 					reg_read(sc, IG4_REG_DATA_CMD);
662 				reg_read(sc, IG4_REG_TX_ABRT_SOURCE);
663 				reg_read(sc, IG4_REG_CLR_INTR);
664 			}
665 			break;
666 		}
667 
668 		rpstart = !stop;
669 	}
670 
671 	if (!allocated)
672 		sx_unlock(&sc->call_lock);
673 	return (error);
674 }
675 
676 int
677 ig4iic_reset(device_t dev, u_char speed, u_char addr, u_char *oldaddr)
678 {
679 	ig4iic_softc_t *sc = device_get_softc(dev);
680 	bool allocated;
681 
682 	allocated = sx_xlocked(&sc->call_lock) != 0;
683 	if (!allocated)
684 		sx_xlock(&sc->call_lock);
685 
686 	/* TODO handle speed configuration? */
687 	if (oldaddr != NULL)
688 		*oldaddr = sc->last_slave << 1;
689 	set_slave_addr(sc, addr >> 1);
690 	if (addr == IIC_UNKNOWN)
691 		sc->slave_valid = false;
692 
693 	if (!allocated)
694 		sx_unlock(&sc->call_lock);
695 	return (0);
696 }
697 
698 int
699 ig4iic_callback(device_t dev, int index, caddr_t data)
700 {
701 	ig4iic_softc_t *sc = device_get_softc(dev);
702 	int error = 0;
703 	int how;
704 
705 	switch (index) {
706 	case IIC_REQUEST_BUS:
707 		/* force polling if ig4iic is requested with IIC_DONTWAIT */
708 		how = *(int *)data;
709 		if ((how & IIC_WAIT) == 0) {
710 			if (sx_try_xlock(&sc->call_lock) == 0)
711 				error = IIC_EBUSBSY;
712 			else
713 				sc->poll = true;
714 		} else
715 			sx_xlock(&sc->call_lock);
716 		break;
717 
718 	case IIC_RELEASE_BUS:
719 		sc->poll = false;
720 		sx_unlock(&sc->call_lock);
721 		break;
722 
723 	default:
724 		error = errno2iic(EINVAL);
725 	}
726 
727 	return (error);
728 }
729 
730 /*
731  * Clock register values can be calculated with following rough equations:
732  * SCL_HCNT = ceil(IC clock rate * tHIGH)
733  * SCL_LCNT = ceil(IC clock rate * tLOW)
734  * SDA_HOLD = ceil(IC clock rate * SDA hold time)
735  * Precise equations take signal's falling, rising and spike suppression
736  * times in to account. They can be found in Synopsys or Intel documentation.
737  *
738  * Here we snarf formulas and defaults from Linux driver to be able to use
739  * timing values provided by Intel LPSS driver "as is".
740  */
741 static int
742 ig4iic_clk_params(const struct ig4_hw *hw, int speed,
743     uint16_t *scl_hcnt, uint16_t *scl_lcnt, uint16_t *sda_hold)
744 {
745 	uint32_t thigh, tlow, tf_max;	/* nsec */
746 	uint32_t sda_fall_time;		/* nsec */
747         uint32_t scl_fall_time;		/* nsec */
748 
749 	switch (speed) {
750 	case IG4_CTL_SPEED_STD:
751 		thigh = IG4_SPEED_STD_THIGH;
752 		tlow = IG4_SPEED_STD_TLOW;
753 		tf_max = IG4_SPEED_STD_TF_MAX;
754 		break;
755 
756 	case IG4_CTL_SPEED_FAST:
757 		thigh = IG4_SPEED_FAST_THIGH;
758 		tlow = IG4_SPEED_FAST_TLOW;
759 		tf_max = IG4_SPEED_FAST_TF_MAX;
760 		break;
761 
762 	default:
763 		return (EINVAL);
764 	}
765 
766 	/* Use slowest falling time defaults to be on the safe side */
767 	sda_fall_time = hw->sda_fall_time == 0 ? tf_max : hw->sda_fall_time;
768 	*scl_hcnt = (uint16_t)
769 	    ((hw->ic_clock_rate * (thigh + sda_fall_time) + 500) / 1000 - 3);
770 
771 	scl_fall_time = hw->scl_fall_time == 0 ? tf_max : hw->scl_fall_time;
772 	*scl_lcnt = (uint16_t)
773 	    ((hw->ic_clock_rate * (tlow + scl_fall_time) + 500) / 1000 - 1);
774 
775 	/*
776 	 * There is no "known good" default value for tHD;DAT so keep SDA_HOLD
777 	 * intact if sda_hold_time value is not provided.
778 	 */
779 	if (hw->sda_hold_time != 0)
780 		*sda_hold = (uint16_t)
781 		    ((hw->ic_clock_rate * hw->sda_hold_time + 500) / 1000);
782 
783 	return (0);
784 }
785 
786 #ifdef DEV_ACPI
787 static ACPI_STATUS
788 ig4iic_acpi_params(ACPI_HANDLE handle, char *method,
789     uint16_t *scl_hcnt, uint16_t *scl_lcnt, uint16_t *sda_hold)
790 {
791 	ACPI_BUFFER buf;
792 	ACPI_OBJECT *obj, *elems;
793 	ACPI_STATUS status;
794 
795 	buf.Pointer = NULL;
796 	buf.Length = ACPI_ALLOCATE_BUFFER;
797 
798 	status = AcpiEvaluateObject(handle, method, NULL, &buf);
799 	if (ACPI_FAILURE(status))
800 		return (status);
801 
802 	status = AE_TYPE;
803 	obj = (ACPI_OBJECT *)buf.Pointer;
804 	if (obj->Type == ACPI_TYPE_PACKAGE && obj->Package.Count == 3) {
805 		elems = obj->Package.Elements;
806 		*scl_hcnt = elems[0].Integer.Value & IG4_SCL_CLOCK_MASK;
807 		*scl_lcnt = elems[1].Integer.Value & IG4_SCL_CLOCK_MASK;
808 		*sda_hold = elems[2].Integer.Value & IG4_SDA_TX_HOLD_MASK;
809 		status = AE_OK;
810 	}
811 
812 	AcpiOsFree(obj);
813 
814 	return (status);
815 }
816 #endif /* DEV_ACPI */
817 
818 static void
819 ig4iic_get_config(ig4iic_softc_t *sc)
820 {
821 	const struct ig4_hw *hw;
822 	uint32_t v;
823 #ifdef DEV_ACPI
824 	ACPI_HANDLE handle;
825 #endif
826 	/* Fetch default hardware config from controller */
827 	sc->cfg.version = reg_read(sc, IG4_REG_COMP_VER);
828 	sc->cfg.bus_speed = reg_read(sc, IG4_REG_CTL) & IG4_CTL_SPEED_MASK;
829 	sc->cfg.ss_scl_hcnt =
830 	    reg_read(sc, IG4_REG_SS_SCL_HCNT) & IG4_SCL_CLOCK_MASK;
831 	sc->cfg.ss_scl_lcnt =
832 	    reg_read(sc, IG4_REG_SS_SCL_LCNT) & IG4_SCL_CLOCK_MASK;
833 	sc->cfg.fs_scl_hcnt =
834 	    reg_read(sc, IG4_REG_FS_SCL_HCNT) & IG4_SCL_CLOCK_MASK;
835 	sc->cfg.fs_scl_lcnt =
836 	    reg_read(sc, IG4_REG_FS_SCL_LCNT) & IG4_SCL_CLOCK_MASK;
837 	sc->cfg.ss_sda_hold = sc->cfg.fs_sda_hold =
838 	    reg_read(sc, IG4_REG_SDA_HOLD) & IG4_SDA_TX_HOLD_MASK;
839 
840 	if (sc->cfg.bus_speed != IG4_CTL_SPEED_STD)
841 		sc->cfg.bus_speed = IG4_CTL_SPEED_FAST;
842 
843 	/* REG_COMP_PARAM1 is not documented in latest Intel specs */
844 	if (sc->version == IG4_HASWELL || sc->version == IG4_ATOM) {
845 		v = reg_read(sc, IG4_REG_COMP_PARAM1);
846 		if (IG4_PARAM1_TXFIFO_DEPTH(v) != 0)
847 			sc->cfg.txfifo_depth = IG4_PARAM1_TXFIFO_DEPTH(v);
848 		if (IG4_PARAM1_RXFIFO_DEPTH(v) != 0)
849 			sc->cfg.rxfifo_depth = IG4_PARAM1_RXFIFO_DEPTH(v);
850 	} else {
851 		/*
852 		 * Hardware does not allow FIFO Threshold Levels value to be
853 		 * set larger than the depth of the buffer. If an attempt is
854 		 * made to do that, the actual value set will be the maximum
855 		 * depth of the buffer.
856 		 */
857 		v = reg_read(sc, IG4_REG_TX_TL);
858 		reg_write(sc, IG4_REG_TX_TL, v | IG4_FIFO_MASK);
859 		sc->cfg.txfifo_depth =
860 		    (reg_read(sc, IG4_REG_TX_TL) & IG4_FIFO_MASK) + 1;
861 		reg_write(sc, IG4_REG_TX_TL, v);
862 		v = reg_read(sc, IG4_REG_RX_TL);
863 		reg_write(sc, IG4_REG_RX_TL, v | IG4_FIFO_MASK);
864 		sc->cfg.rxfifo_depth =
865 		    (reg_read(sc, IG4_REG_RX_TL) & IG4_FIFO_MASK) + 1;
866 		reg_write(sc, IG4_REG_RX_TL, v);
867 	}
868 
869 	/* Override hardware config with IC_clock-based counter values */
870 	if (ig4_timings < 2 && sc->version < nitems(ig4iic_hw)) {
871 		hw = &ig4iic_hw[sc->version];
872 		sc->cfg.bus_speed = IG4_CTL_SPEED_FAST;
873 		ig4iic_clk_params(hw, IG4_CTL_SPEED_STD, &sc->cfg.ss_scl_hcnt,
874 		    &sc->cfg.ss_scl_lcnt, &sc->cfg.ss_sda_hold);
875 		ig4iic_clk_params(hw, IG4_CTL_SPEED_FAST, &sc->cfg.fs_scl_hcnt,
876 		    &sc->cfg.fs_scl_lcnt, &sc->cfg.fs_sda_hold);
877 		if (hw->txfifo_depth != 0)
878 			sc->cfg.txfifo_depth = hw->txfifo_depth;
879 		if (hw->rxfifo_depth != 0)
880 			sc->cfg.rxfifo_depth = hw->rxfifo_depth;
881 	} else if (ig4_timings == 2) {
882 		/*
883 		 * Timings of original ig4 driver:
884 		 * Program based on a 25000 Hz clock.  This is a bit of a
885 		 * hack (obviously).  The defaults are 400 and 470 for standard
886 		 * and 60 and 130 for fast.  The defaults for standard fail
887 		 * utterly (presumably cause an abort) because the clock time
888 		 * is ~18.8ms by default.  This brings it down to ~4ms.
889 		 */
890 		sc->cfg.bus_speed = IG4_CTL_SPEED_STD;
891 		sc->cfg.ss_scl_hcnt = sc->cfg.fs_scl_hcnt = 100;
892 		sc->cfg.ss_scl_lcnt = sc->cfg.fs_scl_lcnt = 125;
893 		if (sc->version == IG4_SKYLAKE)
894 			sc->cfg.ss_sda_hold = sc->cfg.fs_sda_hold = 28;
895 	}
896 
897 #ifdef DEV_ACPI
898 	/* Evaluate SSCN and FMCN ACPI methods to fetch timings */
899 	if (ig4_timings == 0 && (handle = acpi_get_handle(sc->dev)) != NULL) {
900 		ig4iic_acpi_params(handle, "SSCN", &sc->cfg.ss_scl_hcnt,
901 		    &sc->cfg.ss_scl_lcnt, &sc->cfg.ss_sda_hold);
902 		ig4iic_acpi_params(handle, "FMCN", &sc->cfg.fs_scl_hcnt,
903 		    &sc->cfg.fs_scl_lcnt, &sc->cfg.fs_sda_hold);
904 	}
905 #endif
906 
907 	if (bootverbose) {
908 		device_printf(sc->dev, "Controller parameters:\n");
909 		printf("  Speed: %s\n",
910 		    sc->cfg.bus_speed == IG4_CTL_SPEED_STD ? "Std" : "Fast");
911 		printf("  Regs:  HCNT  :LCNT  :SDAHLD\n");
912 		printf("  Std:   0x%04hx:0x%04hx:0x%04hx\n",
913 		    sc->cfg.ss_scl_hcnt, sc->cfg.ss_scl_lcnt,
914 		    sc->cfg.ss_sda_hold);
915 		printf("  Fast:  0x%04hx:0x%04hx:0x%04hx\n",
916 		    sc->cfg.fs_scl_hcnt, sc->cfg.fs_scl_lcnt,
917 		    sc->cfg.fs_sda_hold);
918 		printf("  FIFO:  RX:0x%04x: TX:0x%04x\n",
919 		    sc->cfg.rxfifo_depth, sc->cfg.txfifo_depth);
920 	}
921 }
922 
923 static int
924 ig4iic_set_config(ig4iic_softc_t *sc, bool reset)
925 {
926 	uint32_t v;
927 
928 	v = reg_read(sc, IG4_REG_DEVIDLE_CTRL);
929 	if (IG4_HAS_ADDREGS(sc->version) && (v & IG4_RESTORE_REQUIRED)) {
930 		reg_write(sc, IG4_REG_DEVIDLE_CTRL, IG4_DEVICE_IDLE | IG4_RESTORE_REQUIRED);
931 		reg_write(sc, IG4_REG_DEVIDLE_CTRL, 0);
932 		pause("i2crst", 1);
933 		reset = true;
934 	}
935 
936 	if ((sc->version == IG4_HASWELL || sc->version == IG4_ATOM) && reset) {
937 		reg_write(sc, IG4_REG_RESETS_HSW, IG4_RESETS_ASSERT_HSW);
938 		reg_write(sc, IG4_REG_RESETS_HSW, IG4_RESETS_DEASSERT_HSW);
939 	} else if (IG4_HAS_ADDREGS(sc->version) && reset) {
940 		reg_write(sc, IG4_REG_RESETS_SKL, IG4_RESETS_ASSERT_SKL);
941 		reg_write(sc, IG4_REG_RESETS_SKL, IG4_RESETS_DEASSERT_SKL);
942 	}
943 
944 	if (sc->version == IG4_ATOM)
945 		v = reg_read(sc, IG4_REG_COMP_TYPE);
946 
947 	if (sc->version == IG4_HASWELL || sc->version == IG4_ATOM) {
948 		v = reg_read(sc, IG4_REG_COMP_PARAM1);
949 		v = reg_read(sc, IG4_REG_GENERAL);
950 		/*
951 		 * The content of IG4_REG_GENERAL is different for each
952 		 * controller version.
953 		 */
954 		if (sc->version == IG4_HASWELL &&
955 		    (v & IG4_GENERAL_SWMODE) == 0) {
956 			v |= IG4_GENERAL_SWMODE;
957 			reg_write(sc, IG4_REG_GENERAL, v);
958 			v = reg_read(sc, IG4_REG_GENERAL);
959 		}
960 	}
961 
962 	if (sc->version == IG4_HASWELL) {
963 		v = reg_read(sc, IG4_REG_SW_LTR_VALUE);
964 		v = reg_read(sc, IG4_REG_AUTO_LTR_VALUE);
965 	} else if (IG4_HAS_ADDREGS(sc->version)) {
966 		v = reg_read(sc, IG4_REG_ACTIVE_LTR_VALUE);
967 		v = reg_read(sc, IG4_REG_IDLE_LTR_VALUE);
968 	}
969 
970 	if (sc->version == IG4_HASWELL || sc->version == IG4_ATOM) {
971 		v = reg_read(sc, IG4_REG_COMP_VER);
972 		if (v < IG4_COMP_MIN_VER)
973 			return(ENXIO);
974 	}
975 
976 	if (set_controller(sc, 0)) {
977 		device_printf(sc->dev, "controller error during attach-1\n");
978 		return (ENXIO);
979 	}
980 
981 	reg_read(sc, IG4_REG_CLR_INTR);
982 	reg_write(sc, IG4_REG_INTR_MASK, 0);
983 	sc->intr_mask = 0;
984 
985 	reg_write(sc, IG4_REG_SS_SCL_HCNT, sc->cfg.ss_scl_hcnt);
986 	reg_write(sc, IG4_REG_SS_SCL_LCNT, sc->cfg.ss_scl_lcnt);
987 	reg_write(sc, IG4_REG_FS_SCL_HCNT, sc->cfg.fs_scl_hcnt);
988 	reg_write(sc, IG4_REG_FS_SCL_LCNT, sc->cfg.fs_scl_lcnt);
989 	reg_write(sc, IG4_REG_SDA_HOLD,
990 	    (sc->cfg.bus_speed  & IG4_CTL_SPEED_MASK) == IG4_CTL_SPEED_STD ?
991 	      sc->cfg.ss_sda_hold : sc->cfg.fs_sda_hold);
992 
993 	/*
994 	 * Use a threshold of 1 so we get interrupted on each character,
995 	 * allowing us to use mtx_sleep() in our poll code.  Not perfect
996 	 * but this is better than using DELAY() for receiving data.
997 	 *
998 	 * See ig4_var.h for details on interrupt handler synchronization.
999 	 */
1000 	reg_write(sc, IG4_REG_RX_TL, 0);
1001 	reg_write(sc, IG4_REG_TX_TL, 0);
1002 
1003 	reg_write(sc, IG4_REG_CTL,
1004 		  IG4_CTL_MASTER |
1005 		  IG4_CTL_SLAVE_DISABLE |
1006 		  IG4_CTL_RESTARTEN |
1007 		  (sc->cfg.bus_speed & IG4_CTL_SPEED_MASK));
1008 
1009 	/* Force setting of the target address on the next transfer */
1010 	sc->slave_valid = false;
1011 
1012 	return (0);
1013 }
1014 
1015 /*
1016  * Called from ig4iic_pci_attach/detach()
1017  */
1018 int
1019 ig4iic_attach(ig4iic_softc_t *sc)
1020 {
1021 	int error;
1022 
1023 	mtx_init(&sc->io_lock, "IG4 I/O lock", NULL, MTX_SPIN);
1024 	sx_init(&sc->call_lock, "IG4 call lock");
1025 
1026 	ig4iic_get_config(sc);
1027 
1028 	error = ig4iic_set_config(sc, IG4_HAS_ADDREGS(sc->version));
1029 	if (error)
1030 		goto done;
1031 
1032 	sc->iicbus = device_add_child(sc->dev, "iicbus", -1);
1033 	if (sc->iicbus == NULL) {
1034 		device_printf(sc->dev, "iicbus driver not found\n");
1035 		error = ENXIO;
1036 		goto done;
1037 	}
1038 
1039 	if (set_controller(sc, IG4_I2C_ENABLE)) {
1040 		device_printf(sc->dev, "controller error during attach-2\n");
1041 		error = ENXIO;
1042 		goto done;
1043 	}
1044 	if (set_controller(sc, 0)) {
1045 		device_printf(sc->dev, "controller error during attach-3\n");
1046 		error = ENXIO;
1047 		goto done;
1048 	}
1049 	error = bus_setup_intr(sc->dev, sc->intr_res, INTR_TYPE_MISC | INTR_MPSAFE,
1050 			       ig4iic_intr, NULL, sc, &sc->intr_handle);
1051 	if (error) {
1052 		device_printf(sc->dev,
1053 			      "Unable to setup irq: error %d\n", error);
1054 	}
1055 
1056 	error = bus_generic_attach(sc->dev);
1057 	if (error) {
1058 		device_printf(sc->dev,
1059 			      "failed to attach child: error %d\n", error);
1060 	}
1061 
1062 done:
1063 	return (error);
1064 }
1065 
1066 int
1067 ig4iic_detach(ig4iic_softc_t *sc)
1068 {
1069 	int error;
1070 
1071 	if (device_is_attached(sc->dev)) {
1072 		error = bus_generic_detach(sc->dev);
1073 		if (error)
1074 			return (error);
1075 	}
1076 	if (sc->iicbus)
1077 		device_delete_child(sc->dev, sc->iicbus);
1078 	if (sc->intr_handle)
1079 		bus_teardown_intr(sc->dev, sc->intr_res, sc->intr_handle);
1080 
1081 	sx_xlock(&sc->call_lock);
1082 
1083 	sc->iicbus = NULL;
1084 	sc->intr_handle = NULL;
1085 	reg_write(sc, IG4_REG_INTR_MASK, 0);
1086 	set_controller(sc, 0);
1087 
1088 	sx_xunlock(&sc->call_lock);
1089 
1090 	mtx_destroy(&sc->io_lock);
1091 	sx_destroy(&sc->call_lock);
1092 
1093 	return (0);
1094 }
1095 
1096 int
1097 ig4iic_suspend(ig4iic_softc_t *sc)
1098 {
1099 	int error;
1100 
1101 	/* suspend all children */
1102 	error = bus_generic_suspend(sc->dev);
1103 
1104 	sx_xlock(&sc->call_lock);
1105 	set_controller(sc, 0);
1106 	if (IG4_HAS_ADDREGS(sc->version)) {
1107 		/*
1108 		 * Place the device in the idle state, just to be safe
1109 		 */
1110 		reg_write(sc, IG4_REG_DEVIDLE_CTRL, IG4_DEVICE_IDLE);
1111 		/*
1112 		 * Controller can become dysfunctional if I2C lines are pulled
1113 		 * down when suspend procedure turns off power to I2C device.
1114 		 * Place device in the reset state to avoid this.
1115 		 */
1116 		reg_write(sc, IG4_REG_RESETS_SKL, IG4_RESETS_ASSERT_SKL);
1117 	}
1118 	sx_xunlock(&sc->call_lock);
1119 
1120 	return (error);
1121 }
1122 
1123 int ig4iic_resume(ig4iic_softc_t *sc)
1124 {
1125 	int error;
1126 
1127 	sx_xlock(&sc->call_lock);
1128 	if (ig4iic_set_config(sc, IG4_HAS_ADDREGS(sc->version)))
1129 		device_printf(sc->dev, "controller error during resume\n");
1130 	sx_xunlock(&sc->call_lock);
1131 
1132 	error = bus_generic_resume(sc->dev);
1133 
1134 	return (error);
1135 }
1136 
1137 /*
1138  * Interrupt Operation, see ig4_var.h for locking semantics.
1139  */
1140 static int
1141 ig4iic_intr(void *cookie)
1142 {
1143 	ig4iic_softc_t *sc = cookie;
1144 	int retval = FILTER_STRAY;
1145 
1146 	mtx_lock_spin(&sc->io_lock);
1147 	/* Ignore stray interrupts */
1148 	if (sc->intr_mask != 0 && reg_read(sc, IG4_REG_INTR_STAT) != 0) {
1149 		/* Interrupt bits are cleared in wait_intr() loop */
1150 		ig4iic_set_intr_mask(sc, 0);
1151 		wakeup(sc);
1152 		retval = FILTER_HANDLED;
1153 	}
1154 	mtx_unlock_spin(&sc->io_lock);
1155 
1156 	return (retval);
1157 }
1158 
1159 #define REGDUMP(sc, reg)	\
1160 	device_printf(sc->dev, "  %-23s %08x\n", #reg, reg_read(sc, reg))
1161 
1162 static void
1163 ig4iic_dump(ig4iic_softc_t *sc)
1164 {
1165 	device_printf(sc->dev, "ig4iic register dump:\n");
1166 	REGDUMP(sc, IG4_REG_CTL);
1167 	REGDUMP(sc, IG4_REG_TAR_ADD);
1168 	REGDUMP(sc, IG4_REG_SS_SCL_HCNT);
1169 	REGDUMP(sc, IG4_REG_SS_SCL_LCNT);
1170 	REGDUMP(sc, IG4_REG_FS_SCL_HCNT);
1171 	REGDUMP(sc, IG4_REG_FS_SCL_LCNT);
1172 	REGDUMP(sc, IG4_REG_INTR_STAT);
1173 	REGDUMP(sc, IG4_REG_INTR_MASK);
1174 	REGDUMP(sc, IG4_REG_RAW_INTR_STAT);
1175 	REGDUMP(sc, IG4_REG_RX_TL);
1176 	REGDUMP(sc, IG4_REG_TX_TL);
1177 	REGDUMP(sc, IG4_REG_I2C_EN);
1178 	REGDUMP(sc, IG4_REG_I2C_STA);
1179 	REGDUMP(sc, IG4_REG_TXFLR);
1180 	REGDUMP(sc, IG4_REG_RXFLR);
1181 	REGDUMP(sc, IG4_REG_SDA_HOLD);
1182 	REGDUMP(sc, IG4_REG_TX_ABRT_SOURCE);
1183 	REGDUMP(sc, IG4_REG_SLV_DATA_NACK);
1184 	REGDUMP(sc, IG4_REG_DMA_CTRL);
1185 	REGDUMP(sc, IG4_REG_DMA_TDLR);
1186 	REGDUMP(sc, IG4_REG_DMA_RDLR);
1187 	REGDUMP(sc, IG4_REG_SDA_SETUP);
1188 	REGDUMP(sc, IG4_REG_ENABLE_STATUS);
1189 	REGDUMP(sc, IG4_REG_COMP_PARAM1);
1190 	REGDUMP(sc, IG4_REG_COMP_VER);
1191 	if (sc->version == IG4_ATOM) {
1192 		REGDUMP(sc, IG4_REG_COMP_TYPE);
1193 		REGDUMP(sc, IG4_REG_CLK_PARMS);
1194 	}
1195 	if (sc->version == IG4_HASWELL || sc->version == IG4_ATOM) {
1196 		REGDUMP(sc, IG4_REG_RESETS_HSW);
1197 		REGDUMP(sc, IG4_REG_GENERAL);
1198 	} else if (sc->version == IG4_SKYLAKE) {
1199 		REGDUMP(sc, IG4_REG_RESETS_SKL);
1200 	}
1201 	if (sc->version == IG4_HASWELL) {
1202 		REGDUMP(sc, IG4_REG_SW_LTR_VALUE);
1203 		REGDUMP(sc, IG4_REG_AUTO_LTR_VALUE);
1204 	} else if (IG4_HAS_ADDREGS(sc->version)) {
1205 		REGDUMP(sc, IG4_REG_ACTIVE_LTR_VALUE);
1206 		REGDUMP(sc, IG4_REG_IDLE_LTR_VALUE);
1207 	}
1208 }
1209 #undef REGDUMP
1210 
1211 DRIVER_MODULE(iicbus, ig4iic, iicbus_driver, NULL, NULL);
1212 #ifdef DEV_ACPI
1213 DRIVER_MODULE(acpi_iicbus, ig4iic, acpi_iicbus_driver, NULL, NULL);
1214 #endif
1215 MODULE_DEPEND(ig4iic, iicbus, IICBUS_MINVER, IICBUS_PREFVER, IICBUS_MAXVER);
1216 MODULE_VERSION(ig4iic, 1);
1217