summaryrefslogtreecommitdiff
path: root/power/sdm845.c
blob: a8cc70b8eadb61209f8ef01123fb3c46951f9679 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
/* Copyright 2018 The Chromium OS Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

/*
 * SDM845 SoC power sequencing module for Chrome EC
 *
 * This implements the following features:
 *
 * - Cold reset powers on the AP
 *
 *  When powered off:
 *  - Press power button turns on the AP
 *  - Hold power button turns on the AP, and then 8s later turns it off and
 *    leaves it off until pwron is released and pressed again
 *  - Lid open turns on the AP
 *
 *  When powered on:
 *  - Holding power button for 8s powers off the AP
 *  - Pressing and releasing pwron within that 8s is ignored
 *  - If POWER_GOOD is dropped by the AP, then we power the AP off
 */

#include "charge_state.h"
#include "chipset.h"
#include "common.h"
#include "gpio.h"
#include "hooks.h"
#include "lid_switch.h"
#include "power.h"
#include "power_button.h"
#include "system.h"
#include "task.h"
#include "util.h"

#define CPRINTS(format, args...) cprints(CC_CHIPSET, format, ## args)

/* Masks for power signals */
#define IN_POWER_GOOD		POWER_SIGNAL_MASK(SDM845_POWER_GOOD)
#define IN_AP_RST_ASSERTED	POWER_SIGNAL_MASK(SDM845_AP_RST_ASSERTED)


/* Long power key press to force shutdown */
#define DELAY_FORCE_SHUTDOWN		(8 * SECOND)

/*
 * If the power button is pressed to turn on, then held for this long, we
 * power off.
 *
 * Normal case: User releases power button and chipset_task() goes
 *    into the inner loop, waiting for next event to occur (power button
 *    press or POWER_GOOD == 0).
 */
#define DELAY_SHUTDOWN_ON_POWER_HOLD	(8 * SECOND)

/*
 * After trigger PMIC power sequence, how long it triggers AP to turn on
 * or off. Observed that the worst case is ~150ms. Pick a safe vale.
 */
#define PMIC_POWER_AP_RESPONSE_TIMEOUT	(350 * MSEC)

/*
 * After force off the switch cap, how long the PMIC/AP totally off.
 * Observed that the worst case is 2s. Pick a safe vale.
 */
#define FORCE_OFF_RESPONSE_TIMEOUT	(4 * SECOND)

/* Wait for polling the AP on signal */
#define PMIC_POWER_AP_WAIT		(1 * MSEC)

/* The length of an issued low pulse to the PMIC_RESIN_L signal */
#define PMIC_RESIN_PULSE_LENGTH		(20 * MSEC)

/* The timeout of the check if the system can boot AP */
#define CAN_BOOT_AP_CHECK_TIMEOUT	(500 * MSEC)

/* Wait for polling if the system can boot AP */
#define CAN_BOOT_AP_CHECK_WAIT		(100 * MSEC)

/* The timeout of the check if the switchcap outputs good voltage */
#define SWITCHCAP_PG_CHECK_TIMEOUT	(50 * MSEC)

/* Wait for polling if the switchcap outputs good voltage */
#define SWITCHCAP_PG_CHECK_WAIT		(5 * MSEC)

/* Delay between power-on the system and power-on the PMIC */
#define SYSTEM_POWER_ON_DELAY		(10 * MSEC)

/* TODO(crosbug.com/p/25047): move to HOOK_POWER_BUTTON_CHANGE */
/* 1 if the power button was pressed last time we checked */
static char power_button_was_pressed;

/* 1 if lid-open event has been detected */
static char lid_opened;

/* 1 if AP_RST_L and PS_HOLD is overdriven by EC */
static char ap_rst_overdriven;

/* Time where we will power off, if power button still held down */
static timestamp_t power_off_deadline;

/* Force AP power on (used for recovery keypress) */
static int auto_power_on;

enum power_request_t {
	POWER_REQ_NONE,
	POWER_REQ_OFF,
	POWER_REQ_ON,
	POWER_REQ_RESET,

	POWER_REQ_COUNT,
};

static enum power_request_t power_request;

/**
 * Return values for check_for_power_off_event().
 */
enum power_off_event_t {
	POWER_OFF_CANCEL,
	POWER_OFF_BY_POWER_BUTTON_PRESSED,
	POWER_OFF_BY_LONG_PRESS,
	POWER_OFF_BY_POWER_GOOD_LOST,
	POWER_OFF_BY_POWER_REQ_OFF,
	POWER_OFF_BY_POWER_REQ_RESET,

	POWER_OFF_EVENT_COUNT,
};

/**
 * Return values for check_for_power_on_event().
 */
enum power_on_event_t {
	POWER_ON_CANCEL,
	POWER_ON_BY_IN_POWER_GOOD,
	POWER_ON_BY_AUTO_POWER_ON,
	POWER_ON_BY_LID_OPEN,
	POWER_ON_BY_POWER_BUTTON_PRESSED,
	POWER_ON_BY_POWER_REQ_ON,
	POWER_ON_BY_POWER_REQ_RESET,

	POWER_ON_EVENT_COUNT,
};

/* Issue a request to initiate a reset sequence */
static void request_cold_reset(void)
{
	power_request = POWER_REQ_RESET;
	task_wake(TASK_ID_CHIPSET);
}

/* AP-requested reset GPIO interrupt handlers */
static void chipset_reset_request_handler(void)
{
	CPRINTS("AP wants reset");
	chipset_reset(CHIPSET_RESET_AP_REQ);
}
DECLARE_DEFERRED(chipset_reset_request_handler);

void chipset_reset_request_interrupt(enum gpio_signal signal)
{
	hook_call_deferred(&chipset_reset_request_handler_data, 0);
}

void chipset_warm_reset_interrupt(enum gpio_signal signal)
{
	/*
	 * The warm_reset signal is pulled-up by a rail from PMIC. If the
	 * warm_reset drops, it means:
	 *  * Servo or Cr50 holds the signal, or
	 *  * its pull-up rail POWER_GOOD drops.
	 */
	if (!gpio_get_level(GPIO_WARM_RESET_L)) {
		if (gpio_get_level(GPIO_POWER_GOOD)) {
			/*
			 * Servo or Cr50 holds the WARM_RESET_L signal.
			 *
			 * Overdrive AP_RST_L to hold AP. Overdrive PS_HOLD to
			 * emulate AP being up to trick the PMIC into thinking
			 * there’s nothing weird going on.
			 */
			ap_rst_overdriven = 1;
			gpio_set_flags(GPIO_PS_HOLD, GPIO_INT_BOTH |
				       GPIO_SEL_1P8V | GPIO_OUT_HIGH);
			gpio_set_flags(GPIO_AP_RST_L, GPIO_INT_BOTH |
				       GPIO_SEL_1P8V | GPIO_OUT_LOW);
		} else {
			/*
			 * The pull-up rail POWER_GOOD drops.
			 *
			 * High-Z both AP_RST_L and PS_HOLD to restore their
			 * states.
			 */
			gpio_set_flags(GPIO_AP_RST_L, GPIO_INT_BOTH |
				       GPIO_SEL_1P8V);
			gpio_set_flags(GPIO_PS_HOLD, GPIO_INT_BOTH |
				       GPIO_SEL_1P8V);
			ap_rst_overdriven = 0;
		}
	} else {
		if (ap_rst_overdriven) {
			/*
			 * Servo or Cr50 releases the WARM_RESET_L signal.
			 *
			 * Cold reset the PMIC, doing S0->S5->S0 transition,
			 * by issuing a request to initiate a reset sequence,
			 * to recover the system. The transition to S5 makes
			 * POWER_GOOD drop that triggers an interrupt to
			 * high-Z both AP_RST_L and PS_HOLD.
			 */
			request_cold_reset();
		}
		/* If not overdriven, just a normal power-up, do nothing. */
	}

	power_signal_interrupt(signal);
}

static void sdm845_lid_event(void)
{
	/* Power task only cares about lid-open events */
	if (!lid_is_open())
		return;

	lid_opened = 1;
	task_wake(TASK_ID_CHIPSET);
}
DECLARE_HOOK(HOOK_LID_CHANGE, sdm845_lid_event, HOOK_PRIO_DEFAULT);

static void powerbtn_sdm845_changed(void)
{
	task_wake(TASK_ID_CHIPSET);
}
DECLARE_HOOK(HOOK_POWER_BUTTON_CHANGE, powerbtn_sdm845_changed,
	     HOOK_PRIO_DEFAULT);

/**
 * Wait the switchcap GPIO0 PVC_PG signal asserted.
 *
 * When the output voltage is over the threshold PVC_PG_ADJ,
 * the PVC_PG is asserted.
 *
 * PVG_PG_ADJ is configured to 3.0V.
 * GPIO0 is configured as PVC_PG.
 *
 * @param enable	1 to wait the PMIC/AP on.
			0 to wait the PMIC/AP off.
 */
static void wait_switchcap_power_good(int enable)
{
	timestamp_t poll_deadline;

	poll_deadline = get_time();
	poll_deadline.val += SWITCHCAP_PG_CHECK_TIMEOUT;
	while (enable != gpio_get_level(GPIO_DA9313_GPIO0) &&
	       get_time().val < poll_deadline.val) {
		usleep(SWITCHCAP_PG_CHECK_WAIT);
	}

	/*
	 * Check the timeout case. Just show a message. More check later
	 * will switch the power state.
	 */
	if (enable != gpio_get_level(GPIO_DA9313_GPIO0)) {
		if (enable)
			CPRINTS("SWITCHCAP NO POWER GOOD!");
		else
			CPRINTS("SWITCHCAP STILL POWER GOOD!");
	}

}

/**
 * Get the state of the system power signals.
 *
 * @return 1 if the system is powered, 0 if not
 */
static int is_system_powered(void)
{
	return gpio_get_level(GPIO_SWITCHCAP_ON_L);
}

/**
 * Get the PMIC/AP power signal.
 *
 * We treat the PMIC chips and the AP as a whole here. Don't deal with
 * the individual chip.
 *
 * @return 1 if the PMIC/AP is powered, 0 if not
 */
static int is_pmic_pwron(void)
{
	/* Use POWER_GOOD to indicate PMIC/AP is on/off */
	return gpio_get_level(GPIO_POWER_GOOD);
}

/**
 * Wait the PMIC/AP power-on state.
 *
 * @param enable	1 to wait the PMIC/AP on.
			0 to wait the PMIC/AP off.
 * @param timeout	Number of microsecond of timeout.
 */
static void wait_pmic_pwron(int enable, unsigned int timeout)
{
	timestamp_t poll_deadline;

	/* Check the AP power status */
	if (enable == is_pmic_pwron())
		return;

	poll_deadline = get_time();
	poll_deadline.val += timeout;
	while (enable != is_pmic_pwron() &&
	       get_time().val < poll_deadline.val) {
		usleep(PMIC_POWER_AP_WAIT);
	}

	/* Check the timeout case */
	if (enable != is_pmic_pwron()) {
		if (enable)
			CPRINTS("AP POWER NOT READY!");
		else
			CPRINTS("AP POWER STILL UP!");
	}
}

/**
 * Set the state of the system power signals.
 *
 * The system power signals are the enable pins of SwitchCap and VBOB.
 * They control the power of the set of PMIC chips and the AP.
 *
 * @param enable	1 to enable or 0 to disable
 */
static void set_system_power(int enable)
{
	CPRINTS("%s(%d)", __func__, enable);
	gpio_set_level(GPIO_SWITCHCAP_ON_L, enable);
	wait_switchcap_power_good(enable);
	gpio_set_level(GPIO_VBOB_EN, enable);
	if (enable) {
		usleep(SYSTEM_POWER_ON_DELAY);
	} else {
		/* Ensure POWER_GOOD drop to low if it is a forced shutdown */
		wait_pmic_pwron(0, FORCE_OFF_RESPONSE_TIMEOUT);
	}
}

/**
 * Set the PMIC/AP power-on state.
 *
 * It triggers the PMIC/AP power-on and power-off sequence.
 *
 * @param enable	1 to power the PMIC/AP on.
			0 to power the PMIC/AP off.
 */
static void set_pmic_pwron(int enable)
{
	CPRINTS("%s(%d)", __func__, enable);

	/* Check the PMIC/AP power state */
	if (enable == is_pmic_pwron())
		return;

	/*
	 * Power-on sequence:
	 * 1. Hold down PMIC_KPD_PWR_ODL, which is a power-on trigger
	 * 2. PM845 supplies power to POWER_GOOD
	 * 3. Release PMIC_KPD_PWR_ODL
	 *
	 * Power-off sequence:
	 * 1. Hold down PMIC_KPD_PWR_ODL and PMIC_RESIN_L, which is a power-off
	 *    trigger (requiring reprogramming PMIC registers to make
	 *    PMIC_KPD_PWR_ODL + PMIC_RESIN_L as a shutdown trigger)
	 * 2. PM845 stops supplying power to POWER_GOOD (requiring
	 *    reprogramming PMIC to set the stage-1 and stage-2 reset timers to
	 *    0 such that the pull down happens just after the deboucing time
	 *    of the trigger, like 2ms)
	 * 3. Release PMIC_KPD_PWR_ODL and PMIC_RESIN_L
	 *
	 * If the above PMIC registers not programmed or programmed wrong, it
	 * falls back to the next functions, which cuts off the system power.
	 */

	gpio_set_level(GPIO_PMIC_KPD_PWR_ODL, 0);
	if (!enable)
		gpio_set_level(GPIO_PMIC_RESIN_L, 0);
	wait_pmic_pwron(enable, PMIC_POWER_AP_RESPONSE_TIMEOUT);
	gpio_set_level(GPIO_PMIC_KPD_PWR_ODL, 1);
	if (!enable)
		gpio_set_level(GPIO_PMIC_RESIN_L, 1);
}

enum power_state power_chipset_init(void)
{
	int init_power_state;
	uint32_t reset_flags = system_get_reset_flags();

	/* Enable interrupts */
	gpio_enable_interrupt(GPIO_AP_RST_REQ);
	gpio_enable_interrupt(GPIO_WARM_RESET_L);
	gpio_enable_interrupt(GPIO_POWER_GOOD);

	/*
	 * Force the AP shutdown unless we are doing SYSJUMP. Otherwise,
	 * the AP could stay in strange state.
	 */
	if (!(reset_flags & EC_RESET_FLAG_SYSJUMP)) {
		CPRINTS("not sysjump; forcing system shutdown");
		set_system_power(0);
		init_power_state = POWER_G3;
	} else {
		/* In the SYSJUMP case, we check if the AP is on */
		if (power_get_signals() & IN_POWER_GOOD) {
			CPRINTS("SOC ON");
			init_power_state = POWER_S0;
			/* Disable idle task deep sleep when in S0 */
			disable_sleep(SLEEP_MASK_AP_RUN);
		} else {
			CPRINTS("SOC OFF");
			init_power_state = POWER_G3;
		}
	}

	/* Leave power off only if requested by reset flags */
	if (!(reset_flags & EC_RESET_FLAG_AP_OFF) &&
	    !(reset_flags & EC_RESET_FLAG_SYSJUMP)) {
		CPRINTS("auto_power_on set due to reset_flag 0x%x",
			system_get_reset_flags());
		auto_power_on = 1;
	}

	if (battery_is_present() == BP_YES) {
		/*
		 * (crosbug.com/p/28289): Wait battery stable.
		 * Some batteries use clock stretching feature, which requires
		 * more time to be stable.
		 */
		battery_wait_for_stable();
	}

	return init_power_state;
}

/*****************************************************************************/

/**
 * Power off the AP
 */
static void power_off(void)
{
	/* Check the power off status */
	if (!is_system_powered())
		return;

	/* Call hooks before we drop power rails */
	hook_notify(HOOK_CHIPSET_SHUTDOWN);

	/* Do a graceful way to shutdown PMIC/AP first */
	set_pmic_pwron(0);

	/* Disable signal interrupts, as they are floating when switchcap off */
	power_signal_disable_interrupt(GPIO_AP_RST_L);
	power_signal_disable_interrupt(GPIO_PMIC_FAULT_L);

	/* Force to switch off all rails */
	set_system_power(0);

	/* Turn off the 3.3V and 5V rails. */
	gpio_set_level(GPIO_EN_PP3300_A, 0);
#ifdef CONFIG_POWER_PP5000_CONTROL
	power_5v_enable(task_get_current(), 0);
#else /* !defined(CONFIG_POWER_PP5000_CONTROL) */
	gpio_set_level(GPIO_EN_PP5000, 0);
#endif /* defined(CONFIG_POWER_PP5000_CONTROL) */

	lid_opened = 0;
	enable_sleep(SLEEP_MASK_AP_RUN);
	CPRINTS("power shutdown complete");

	/* Call hooks after we drop power rails */
	hook_notify(HOOK_CHIPSET_SHUTDOWN_COMPLETE);
}

/**
 * Check if the power is enough to boot the AP.
 */
static int power_is_enough(void)
{
	timestamp_t poll_deadline;

	/* If powered by adapter only, wait a while for PD negoiation. */
	poll_deadline = get_time();
	poll_deadline.val += CAN_BOOT_AP_CHECK_TIMEOUT;

	/*
	 * Wait for PD negotiation. If a system with drained battery, don't
	 * waste the time and exit the loop.
	 */
	while (!system_can_boot_ap() && !charge_want_shutdown() &&
		get_time().val < poll_deadline.val) {
		usleep(CAN_BOOT_AP_CHECK_WAIT);
	}

	return system_can_boot_ap() && !charge_want_shutdown();
}

/**
 * Power on the AP
 */
static void power_on(void)
{
	/*
	 * If no enough power, return and the state machine will transition
	 * back to S5.
	 */
	if (!power_is_enough())
		return;

	/*
	 * When power_on() is called, we are at S5S3. Initialize components
	 * to ready state before AP is up.
	 */
	hook_notify(HOOK_CHIPSET_PRE_INIT);

	/* Enable the 3.3V and 5V rail. */
	gpio_set_level(GPIO_EN_PP3300_A, 1);
#ifdef CONFIG_POWER_PP5000_CONTROL
	power_5v_enable(task_get_current(), 1);
#else /* !defined(CONFIG_POWER_PP5000_CONTROL) */
	gpio_set_level(GPIO_EN_PP5000, 1);
#endif /* defined(CONFIG_POWER_PP5000_CONTROL) */

	set_system_power(1);

	/* Enable signal interrupts */
	power_signal_enable_interrupt(GPIO_AP_RST_L);
	power_signal_enable_interrupt(GPIO_PMIC_FAULT_L);

	set_pmic_pwron(1);

	disable_sleep(SLEEP_MASK_AP_RUN);

	CPRINTS("AP running ...");
}

/**
 * Check if there has been a power-on event
 *
 * This checks all power-on event signals and returns non-zero if any have been
 * triggered (with debounce taken into account).
 *
 * @return non-zero if there has been a power-on event, 0 if not.
 */
static uint8_t check_for_power_on_event(void)
{
	int ap_off_flag;

	ap_off_flag = system_get_reset_flags() & EC_RESET_FLAG_AP_OFF;
	system_clear_reset_flags(EC_RESET_FLAG_AP_OFF);

	if (power_request == POWER_REQ_ON) {
		power_request = POWER_REQ_NONE;
		return POWER_ON_BY_POWER_REQ_ON;
	} else if (power_request == POWER_REQ_RESET) {
		power_request = POWER_REQ_NONE;
		return POWER_ON_BY_POWER_REQ_RESET;
	}
	/* Clear invalid request */
	power_request = POWER_REQ_NONE;

	/* check if system is already ON */
	if (power_get_signals() & IN_POWER_GOOD) {
		if (ap_off_flag) {
			CPRINTS("system is on, but EC_RESET_FLAG_AP_OFF is on");
			return POWER_ON_CANCEL;
		}
		CPRINTS("system is on, thus clear auto_power_on");
		/* no need to arrange another power on */
		auto_power_on = 0;
		return POWER_ON_BY_IN_POWER_GOOD;
	}
	if (ap_off_flag) {
		CPRINTS("EC_RESET_FLAG_AP_OFF is on");
		power_off();
		return POWER_ON_CANCEL;
	}

	CPRINTS("POWER_GOOD is not asserted");

	/* power on requested at EC startup for recovery */
	if (auto_power_on) {
		auto_power_on = 0;
		return POWER_ON_BY_AUTO_POWER_ON;
	}

	/* Check lid open */
	if (lid_opened) {
		lid_opened = 0;
		return POWER_ON_BY_LID_OPEN;
	}

	/* check for power button press */
	if (power_button_is_pressed())
		return POWER_ON_BY_POWER_BUTTON_PRESSED;

	return POWER_OFF_CANCEL;
}

/**
 * Check for some event triggering the shutdown.
 *
 * It can be either a long power button press or a shutdown triggered from the
 * AP and detected by reading POWER_GOOD.
 *
 * @return non-zero if a shutdown should happen, 0 if not
 */
static uint8_t check_for_power_off_event(void)
{
	timestamp_t now;
	int pressed = 0;

	if (power_request == POWER_REQ_OFF) {
		power_request = POWER_REQ_NONE;
		return POWER_OFF_BY_POWER_REQ_OFF;
	} else if (power_request == POWER_REQ_RESET) {
		/*
		 * The power_request flag will be cleared later
		 * in check_for_power_on_event() in S5.
		 */
		return POWER_OFF_BY_POWER_REQ_RESET;
	}
	/* Clear invalid request */
	power_request = POWER_REQ_NONE;

	/*
	 * Check for power button press.
	 */
	if (power_button_is_pressed())
		pressed = POWER_OFF_BY_POWER_BUTTON_PRESSED;

	now = get_time();
	if (pressed) {
		if (!power_button_was_pressed) {
			power_off_deadline.val = now.val + DELAY_FORCE_SHUTDOWN;
			CPRINTS("power waiting for long press %u",
				power_off_deadline.le.lo);
			/* Ensure we will wake up to check the power key */
			timer_arm(power_off_deadline, TASK_ID_CHIPSET);
		} else if (timestamp_expired(power_off_deadline, &now)) {
			power_off_deadline.val = 0;
			CPRINTS("power off after long press now=%u, %u",
				now.le.lo, power_off_deadline.le.lo);
			return POWER_OFF_BY_LONG_PRESS;
		}
	} else if (power_button_was_pressed) {
		CPRINTS("power off cancel");
		timer_cancel(TASK_ID_CHIPSET);
	}

	power_button_was_pressed = pressed;

	/* POWER_GOOD released by AP : shutdown immediately */
	if (!power_has_signals(IN_POWER_GOOD)) {
		if (power_button_was_pressed)
			timer_cancel(TASK_ID_CHIPSET);

		CPRINTS("POWER_GOOD is lost");
		return POWER_OFF_BY_POWER_GOOD_LOST;
	}

	return POWER_OFF_CANCEL;
}

/*****************************************************************************/
/* Chipset interface */

void chipset_force_shutdown(enum chipset_shutdown_reason reason)
{
	CPRINTS("%s(%d)", __func__, reason);
	report_ap_reset(reason);

	/* Issue a request to initiate a power-off sequence */
	power_request = POWER_REQ_OFF;
	task_wake(TASK_ID_CHIPSET);
}

void chipset_reset(enum chipset_reset_reason reason)
{
	int rv;

	CPRINTS("%s(%d)", __func__, reason);
	report_ap_reset(reason);

	/*
	 * Warm reset sequence:
	 * 1. Issue a low pulse to PMIC_RESIN_L, which triggers PMIC
	 *    to do a warm reset (requiring reprogramming PMIC registers
	 *    to make PMIC_RESIN_L as a warm reset trigger).
	 * 2. PMIC then issues a low pulse to AP_RST_L to reset AP.
	 *    EC monitors the signal to see any low pulse.
	 *    2.1. If a low pulse found, done.
	 *    2.2. If a low pulse not found (the above PMIC registers
	 *         not programmed or programmed wrong), issue a request
	 *         to initiate a cold reset power sequence.
	 */

	gpio_set_level(GPIO_PMIC_RESIN_L, 0);
	usleep(PMIC_RESIN_PULSE_LENGTH);
	gpio_set_level(GPIO_PMIC_RESIN_L, 1);

	rv = power_wait_signals_timeout(IN_AP_RST_ASSERTED,
					PMIC_POWER_AP_RESPONSE_TIMEOUT);
	/* Exception case: PMIC not work as expected, request a cold reset */
	if (rv != EC_SUCCESS)
		request_cold_reset();
}

/**
 * Power handler for steady states
 *
 * @param state		Current power state
 * @return Updated power state
 */
enum power_state power_handle_state(enum power_state state)
{
	uint8_t value;
	static uint8_t boot_from_g3, shutdown_from_s0;

	switch (state) {
	case POWER_G3:
		boot_from_g3 = check_for_power_on_event();
		if (boot_from_g3)
			return POWER_G3S5;
		break;

	case POWER_G3S5:
		return POWER_S5;

	case POWER_S5:
		if (boot_from_g3) {
			value = boot_from_g3;
			boot_from_g3 = 0;
		} else {
			value = check_for_power_on_event();
		}

		if (value) {
			CPRINTS("power on %d", value);
			return POWER_S5S3;
		}
		break;

	case POWER_S5S3:
		/*
		 * Wait for power button release before actually boot AP.
		 * It may be a long-hold power button with volume buttons
		 * to trigger the recovery button. We don't want AP up
		 * during the long-hold.
		 */
		power_button_wait_for_release(-1);

		power_on();
		if (power_wait_signals(IN_POWER_GOOD) != EC_SUCCESS) {
			CPRINTS("POWER_GOOD not seen in time");
			set_system_power(0);
			return POWER_S5;
		}

		CPRINTS("POWER_GOOD seen");
		/* Call hooks now that AP is running */
		hook_notify(HOOK_CHIPSET_STARTUP);
		return POWER_S3;

	case POWER_S3:
		if (shutdown_from_s0) {
			value = shutdown_from_s0;
			shutdown_from_s0 = 0;
		} else {
			value = check_for_power_off_event();
		}

		if (value) {
			CPRINTS("power off %d", value);
			return POWER_S3S5;
		}
		/* Go to S3S0 directly, as don't know if it is in suspend */
		return POWER_S3S0;

	case POWER_S3S0:
		hook_notify(HOOK_CHIPSET_RESUME);
		return POWER_S0;

	case POWER_S0:
		shutdown_from_s0 = check_for_power_off_event();
		if (shutdown_from_s0)
			return POWER_S0S3;
		break;

	case POWER_S0S3:
		/*
		 * If the power button is pressing, we need cancel the long
		 * press timer, otherwise EC will crash.
		 */
		if (power_button_was_pressed)
			timer_cancel(TASK_ID_CHIPSET);

		/* Call hooks here since we don't know it prior to AP suspend */
		hook_notify(HOOK_CHIPSET_SUSPEND);
		return POWER_S3;

	case POWER_S3S5:
		power_off();
		/*
		 * Wait forever for the release of the power button; otherwise,
		 * this power button press will then trigger a power-on in S5.
		 */
		power_button_wait_for_release(-1);
		power_button_was_pressed = 0;
		return POWER_S5;

	case POWER_S5G3:
		return POWER_G3;
	}

	return state;
}

/*****************************************************************************/
/* Console debug command */

static const char *power_req_name[POWER_REQ_COUNT] = {
	"none",
	"off",
	"on",
};

/* Power states that we can report */
enum power_state_t {
	PSTATE_UNKNOWN,
	PSTATE_OFF,
	PSTATE_ON,
	PSTATE_COUNT,
};

static const char * const state_name[] = {
	"unknown",
	"off",
	"on",
};

static int command_power(int argc, char **argv)
{
	int v;

	if (argc < 2) {
		enum power_state_t state;

		state = PSTATE_UNKNOWN;
		if (chipset_in_state(CHIPSET_STATE_ANY_OFF))
			state = PSTATE_OFF;
		if (chipset_in_state(CHIPSET_STATE_ON))
			state = PSTATE_ON;
		ccprintf("%s\n", state_name[state]);

		return EC_SUCCESS;
	}

	if (!parse_bool(argv[1], &v))
		return EC_ERROR_PARAM1;

	power_request = v ? POWER_REQ_ON : POWER_REQ_OFF;
	ccprintf("Requesting power %s\n", power_req_name[power_request]);
	task_wake(TASK_ID_CHIPSET);

	return EC_SUCCESS;
}
DECLARE_CONSOLE_COMMAND(power, command_power,
			"on/off",
			"Turn AP power on/off");