summaryrefslogtreecommitdiffstats
path: root/drivers/pinctrl/pinctrl-amd.c
blob: e18ebb2c78d93e1530aafde82a73652a3f31800f (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
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
/*
 * GPIO driver for AMD
 *
 * Copyright (c) 2014,2015 AMD Corporation.
 * Authors: Ken Xue <Ken.Xue@amd.com>
 *      Wu, Jeff <Jeff.Wu@amd.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * Contact Information: Nehal Shah <Nehal-bakulchandra.Shah@amd.com>
 *			Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
 *
 */

#include <linux/err.h>
#include <linux/bug.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/compiler.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/log2.h>
#include <linux/io.h>
#include <linux/gpio/driver.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/mutex.h>
#include <linux/acpi.h>
#include <linux/seq_file.h>
#include <linux/interrupt.h>
#include <linux/list.h>
#include <linux/bitops.h>
#include <linux/pinctrl/pinconf.h>
#include <linux/pinctrl/pinconf-generic.h>

#include "core.h"
#include "pinctrl-utils.h"
#include "pinctrl-amd.h"

static int amd_gpio_get_direction(struct gpio_chip *gc, unsigned offset)
{
	unsigned long flags;
	u32 pin_reg;
	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);

	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
	pin_reg = readl(gpio_dev->base + offset * 4);
	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);

	return !(pin_reg & BIT(OUTPUT_ENABLE_OFF));
}

static int amd_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
{
	unsigned long flags;
	u32 pin_reg;
	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);

	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
	pin_reg = readl(gpio_dev->base + offset * 4);
	pin_reg &= ~BIT(OUTPUT_ENABLE_OFF);
	writel(pin_reg, gpio_dev->base + offset * 4);
	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);

	return 0;
}

static int amd_gpio_direction_output(struct gpio_chip *gc, unsigned offset,
		int value)
{
	u32 pin_reg;
	unsigned long flags;
	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);

	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
	pin_reg = readl(gpio_dev->base + offset * 4);
	pin_reg |= BIT(OUTPUT_ENABLE_OFF);
	if (value)
		pin_reg |= BIT(OUTPUT_VALUE_OFF);
	else
		pin_reg &= ~BIT(OUTPUT_VALUE_OFF);
	writel(pin_reg, gpio_dev->base + offset * 4);
	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);

	return 0;
}

static int amd_gpio_get_value(struct gpio_chip *gc, unsigned offset)
{
	u32 pin_reg;
	unsigned long flags;
	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);

	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
	pin_reg = readl(gpio_dev->base + offset * 4);
	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);

	return !!(pin_reg & BIT(PIN_STS_OFF));
}

static void amd_gpio_set_value(struct gpio_chip *gc, unsigned offset, int value)
{
	u32 pin_reg;
	unsigned long flags;
	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);

	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
	pin_reg = readl(gpio_dev->base + offset * 4);
	if (value)
		pin_reg |= BIT(OUTPUT_VALUE_OFF);
	else
		pin_reg &= ~BIT(OUTPUT_VALUE_OFF);
	writel(pin_reg, gpio_dev->base + offset * 4);
	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
}

static int amd_gpio_set_debounce(struct gpio_chip *gc, unsigned offset,
		unsigned debounce)
{
	u32 time;
	u32 pin_reg;
	int ret = 0;
	unsigned long flags;
	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);

	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
	pin_reg = readl(gpio_dev->base + offset * 4);

	if (debounce) {
		pin_reg |= DB_TYPE_REMOVE_GLITCH << DB_CNTRL_OFF;
		pin_reg &= ~DB_TMR_OUT_MASK;
		/*
		Debounce	Debounce	Timer	Max
		TmrLarge	TmrOutUnit	Unit	Debounce
							Time
		0	0	61 usec (2 RtcClk)	976 usec
		0	1	244 usec (8 RtcClk)	3.9 msec
		1	0	15.6 msec (512 RtcClk)	250 msec
		1	1	62.5 msec (2048 RtcClk)	1 sec
		*/

		if (debounce < 61) {
			pin_reg |= 1;
			pin_reg &= ~BIT(DB_TMR_OUT_UNIT_OFF);
			pin_reg &= ~BIT(DB_TMR_LARGE_OFF);
		} else if (debounce < 976) {
			time = debounce / 61;
			pin_reg |= time & DB_TMR_OUT_MASK;
			pin_reg &= ~BIT(DB_TMR_OUT_UNIT_OFF);
			pin_reg &= ~BIT(DB_TMR_LARGE_OFF);
		} else if (debounce < 3900) {
			time = debounce / 244;
			pin_reg |= time & DB_TMR_OUT_MASK;
			pin_reg |= BIT(DB_TMR_OUT_UNIT_OFF);
			pin_reg &= ~BIT(DB_TMR_LARGE_OFF);
		} else if (debounce < 250000) {
			time = debounce / 15600;
			pin_reg |= time & DB_TMR_OUT_MASK;
			pin_reg &= ~BIT(DB_TMR_OUT_UNIT_OFF);
			pin_reg |= BIT(DB_TMR_LARGE_OFF);
		} else if (debounce < 1000000) {
			time = debounce / 62500;
			pin_reg |= time & DB_TMR_OUT_MASK;
			pin_reg |= BIT(DB_TMR_OUT_UNIT_OFF);
			pin_reg |= BIT(DB_TMR_LARGE_OFF);
		} else {
			pin_reg &= ~DB_CNTRl_MASK;
			ret = -EINVAL;
		}
	} else {
		pin_reg &= ~BIT(DB_TMR_OUT_UNIT_OFF);
		pin_reg &= ~BIT(DB_TMR_LARGE_OFF);
		pin_reg &= ~DB_TMR_OUT_MASK;
		pin_reg &= ~DB_CNTRl_MASK;
	}
	writel(pin_reg, gpio_dev->base + offset * 4);
	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);

	return ret;
}

static int amd_gpio_set_config(struct gpio_chip *gc, unsigned offset,
			       unsigned long config)
{
	u32 debounce;

	if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE)
		return -ENOTSUPP;

	debounce = pinconf_to_config_argument(config);
	return amd_gpio_set_debounce(gc, offset, debounce);
}

#ifdef CONFIG_DEBUG_FS
static void amd_gpio_dbg_show(struct seq_file *s, struct gpio_chip *gc)
{
	u32 pin_reg;
	unsigned long flags;
	unsigned int bank, i, pin_num;
	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);

	char *level_trig;
	char *active_level;
	char *interrupt_enable;
	char *interrupt_mask;
	char *wake_cntrl0;
	char *wake_cntrl1;
	char *wake_cntrl2;
	char *pin_sts;
	char *pull_up_sel;
	char *pull_up_enable;
	char *pull_down_enable;
	char *output_value;
	char *output_enable;

	for (bank = 0; bank < gpio_dev->hwbank_num; bank++) {
		seq_printf(s, "GPIO bank%d\t", bank);

		switch (bank) {
		case 0:
			i = 0;
			pin_num = AMD_GPIO_PINS_BANK0;
			break;
		case 1:
			i = 64;
			pin_num = AMD_GPIO_PINS_BANK1 + i;
			break;
		case 2:
			i = 128;
			pin_num = AMD_GPIO_PINS_BANK2 + i;
			break;
		case 3:
			i = 192;
			pin_num = AMD_GPIO_PINS_BANK3 + i;
			break;
		default:
			/* Illegal bank number, ignore */
			continue;
		}
		for (; i < pin_num; i++) {
			seq_printf(s, "pin%d\t", i);
			raw_spin_lock_irqsave(&gpio_dev->lock, flags);
			pin_reg = readl(gpio_dev->base + i * 4);
			raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);

			if (pin_reg & BIT(INTERRUPT_ENABLE_OFF)) {
				u8 level = (pin_reg >> ACTIVE_LEVEL_OFF) &
						ACTIVE_LEVEL_MASK;
				interrupt_enable = "interrupt is enabled|";

				if (level == ACTIVE_LEVEL_HIGH)
					active_level = "Active high|";
				else if (level == ACTIVE_LEVEL_LOW)
					active_level = "Active low|";
				else if (!(pin_reg & BIT(LEVEL_TRIG_OFF)) &&
					 level == ACTIVE_LEVEL_BOTH)
					active_level = "Active on both|";
				else
					active_level = "Unknown Active level|";

				if (pin_reg & BIT(LEVEL_TRIG_OFF))
					level_trig = "Level trigger|";
				else
					level_trig = "Edge trigger|";

			} else {
				interrupt_enable =
					"interrupt is disabled|";
				active_level = " ";
				level_trig = " ";
			}

			if (pin_reg & BIT(INTERRUPT_MASK_OFF))
				interrupt_mask =
					"interrupt is unmasked|";
			else
				interrupt_mask =
					"interrupt is masked|";

			if (pin_reg & BIT(WAKE_CNTRL_OFF_S0I3))
				wake_cntrl0 = "enable wakeup in S0i3 state|";
			else
				wake_cntrl0 = "disable wakeup in S0i3 state|";

			if (pin_reg & BIT(WAKE_CNTRL_OFF_S3))
				wake_cntrl1 = "enable wakeup in S3 state|";
			else
				wake_cntrl1 = "disable wakeup in S3 state|";

			if (pin_reg & BIT(WAKE_CNTRL_OFF_S4))
				wake_cntrl2 = "enable wakeup in S4/S5 state|";
			else
				wake_cntrl2 = "disable wakeup in S4/S5 state|";

			if (pin_reg & BIT(PULL_UP_ENABLE_OFF)) {
				pull_up_enable = "pull-up is enabled|";
				if (pin_reg & BIT(PULL_UP_SEL_OFF))
					pull_up_sel = "8k pull-up|";
				else
					pull_up_sel = "4k pull-up|";
			} else {
				pull_up_enable = "pull-up is disabled|";
				pull_up_sel = " ";
			}

			if (pin_reg & BIT(PULL_DOWN_ENABLE_OFF))
				pull_down_enable = "pull-down is enabled|";
			else
				pull_down_enable = "Pull-down is disabled|";

			if (pin_reg & BIT(OUTPUT_ENABLE_OFF)) {
				pin_sts = " ";
				output_enable = "output is enabled|";
				if (pin_reg & BIT(OUTPUT_VALUE_OFF))
					output_value = "output is high|";
				else
					output_value = "output is low|";
			} else {
				output_enable = "output is disabled|";
				output_value = " ";

				if (pin_reg & BIT(PIN_STS_OFF))
					pin_sts = "input is high|";
				else
					pin_sts = "input is low|";
			}

			seq_printf(s, "%s %s %s %s %s %s\n"
				" %s %s %s %s %s %s %s 0x%x\n",
				level_trig, active_level, interrupt_enable,
				interrupt_mask, wake_cntrl0, wake_cntrl1,
				wake_cntrl2, pin_sts, pull_up_sel,
				pull_up_enable, pull_down_enable,
				output_value, output_enable, pin_reg);
		}
	}
}
#else
#define amd_gpio_dbg_show NULL
#endif

static void amd_gpio_irq_enable(struct irq_data *d)
{
	u32 pin_reg;
	unsigned long flags;
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);

	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
	pin_reg = readl(gpio_dev->base + (d->hwirq)*4);
	pin_reg |= BIT(INTERRUPT_ENABLE_OFF);
	pin_reg |= BIT(INTERRUPT_MASK_OFF);
	writel(pin_reg, gpio_dev->base + (d->hwirq)*4);
	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
}

static void amd_gpio_irq_disable(struct irq_data *d)
{
	u32 pin_reg;
	unsigned long flags;
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);

	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
	pin_reg = readl(gpio_dev->base + (d->hwirq)*4);
	pin_reg &= ~BIT(INTERRUPT_ENABLE_OFF);
	pin_reg &= ~BIT(INTERRUPT_MASK_OFF);
	writel(pin_reg, gpio_dev->base + (d->hwirq)*4);
	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
}

static void amd_gpio_irq_mask(struct irq_data *d)
{
	u32 pin_reg;
	unsigned long flags;
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);

	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
	pin_reg = readl(gpio_dev->base + (d->hwirq)*4);
	pin_reg &= ~BIT(INTERRUPT_MASK_OFF);
	writel(pin_reg, gpio_dev->base + (d->hwirq)*4);
	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
}

static void amd_gpio_irq_unmask(struct irq_data *d)
{
	u32 pin_reg;
	unsigned long flags;
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);

	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
	pin_reg = readl(gpio_dev->base + (d->hwirq)*4);
	pin_reg |= BIT(INTERRUPT_MASK_OFF);
	writel(pin_reg, gpio_dev->base + (d->hwirq)*4);
	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
}

static void amd_gpio_irq_eoi(struct irq_data *d)
{
	u32 reg;
	unsigned long flags;
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);

	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
	reg = readl(gpio_dev->base + WAKE_INT_MASTER_REG);
	reg |= EOI_MASK;
	writel(reg, gpio_dev->base + WAKE_INT_MASTER_REG);
	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
}

static int amd_gpio_irq_set_type(struct irq_data *d, unsigned int type)
{
	int ret = 0;
	u32 pin_reg, pin_reg_irq_en, mask;
	unsigned long flags, irq_flags;
	struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
	struct amd_gpio *gpio_dev = gpiochip_get_data(gc);

	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
	pin_reg = readl(gpio_dev->base + (d->hwirq)*4);

	/* Ignore the settings coming from the client and
	 * read the values from the ACPI tables
	 * while setting the trigger type
	 */

	irq_flags = irq_get_trigger_type(d->irq);
	if (irq_flags != IRQ_TYPE_NONE)
		type = irq_flags;

	switch (type & IRQ_TYPE_SENSE_MASK) {
	case IRQ_TYPE_EDGE_RISING:
		pin_reg &= ~BIT(LEVEL_TRIG_OFF);
		pin_reg &= ~(ACTIVE_LEVEL_MASK << ACTIVE_LEVEL_OFF);
		pin_reg |= ACTIVE_HIGH << ACTIVE_LEVEL_OFF;
		pin_reg |= DB_TYPE_REMOVE_GLITCH << DB_CNTRL_OFF;
		irq_set_handler_locked(d, handle_edge_irq);
		break;

	case IRQ_TYPE_EDGE_FALLING:
		pin_reg &= ~BIT(LEVEL_TRIG_OFF);
		pin_reg &= ~(ACTIVE_LEVEL_MASK << ACTIVE_LEVEL_OFF);
		pin_reg |= ACTIVE_LOW << ACTIVE_LEVEL_OFF;
		pin_reg |= DB_TYPE_REMOVE_GLITCH << DB_CNTRL_OFF;
		irq_set_handler_locked(d, handle_edge_irq);
		break;

	case IRQ_TYPE_EDGE_BOTH:
		pin_reg &= ~BIT(LEVEL_TRIG_OFF);
		pin_reg &= ~(ACTIVE_LEVEL_MASK << ACTIVE_LEVEL_OFF);
		pin_reg |= BOTH_EADGE << ACTIVE_LEVEL_OFF;
		pin_reg |= DB_TYPE_REMOVE_GLITCH << DB_CNTRL_OFF;
		irq_set_handler_locked(d, handle_edge_irq);
		break;

	case IRQ_TYPE_LEVEL_HIGH:
		pin_reg |= LEVEL_TRIGGER << LEVEL_TRIG_OFF;
		pin_reg &= ~(ACTIVE_LEVEL_MASK << ACTIVE_LEVEL_OFF);
		pin_reg |= ACTIVE_HIGH << ACTIVE_LEVEL_OFF;
		pin_reg &= ~(DB_CNTRl_MASK << DB_CNTRL_OFF);
		pin_reg |= DB_TYPE_PRESERVE_LOW_GLITCH << DB_CNTRL_OFF;
		irq_set_handler_locked(d, handle_level_irq);
		break;

	case IRQ_TYPE_LEVEL_LOW:
		pin_reg |= LEVEL_TRIGGER << LEVEL_TRIG_OFF;
		pin_reg &= ~(ACTIVE_LEVEL_MASK << ACTIVE_LEVEL_OFF);
		pin_reg |= ACTIVE_LOW << ACTIVE_LEVEL_OFF;
		pin_reg &= ~(DB_CNTRl_MASK << DB_CNTRL_OFF);
		pin_reg |= DB_TYPE_PRESERVE_HIGH_GLITCH << DB_CNTRL_OFF;
		irq_set_handler_locked(d, handle_level_irq);
		break;

	case IRQ_TYPE_NONE:
		break;

	default:
		dev_err(&gpio_dev->pdev->dev, "Invalid type value\n");
		ret = -EINVAL;
	}

	pin_reg |= CLR_INTR_STAT << INTERRUPT_STS_OFF;
	/*
	 * If WAKE_INT_MASTER_REG.MaskStsEn is set, a software write to the
	 * debounce registers of any GPIO will block wake/interrupt status
	 * generation for *all* GPIOs for a length of time that depends on
	 * WAKE_INT_MASTER_REG.MaskStsLength[11:0].  During this period the
	 * INTERRUPT_ENABLE bit will read as 0.
	 *
	 * We temporarily enable irq for the GPIO whose configuration is
	 * changing, and then wait for it to read back as 1 to know when
	 * debounce has settled and then disable the irq again.
	 * We do this polling with the spinlock held to ensure other GPIO
	 * access routines do not read an incorrect value for the irq enable
	 * bit of other GPIOs.  We keep the GPIO masked while polling to avoid
	 * spurious irqs, and disable the irq again after polling.
	 */
	mask = BIT(INTERRUPT_ENABLE_OFF);
	pin_reg_irq_en = pin_reg;
	pin_reg_irq_en |= mask;
	pin_reg_irq_en &= ~BIT(INTERRUPT_MASK_OFF);
	writel(pin_reg_irq_en, gpio_dev->base + (d->hwirq)*4);
	while ((readl(gpio_dev->base + (d->hwirq)*4) & mask) != mask)
		continue;
	writel(pin_reg, gpio_dev->base + (d->hwirq)*4);
	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);

	return ret;
}

static void amd_irq_ack(struct irq_data *d)
{
	/*
	 * based on HW design,there is no need to ack HW
	 * before handle current irq. But this routine is
	 * necessary for handle_edge_irq
	*/
}

static struct irq_chip amd_gpio_irqchip = {
	.name         = "amd_gpio",
	.irq_ack      = amd_irq_ack,
	.irq_enable   = amd_gpio_irq_enable,
	.irq_disable  = amd_gpio_irq_disable,
	.irq_mask     = amd_gpio_irq_mask,
	.irq_unmask   = amd_gpio_irq_unmask,
	.irq_eoi      = amd_gpio_irq_eoi,
	.irq_set_type = amd_gpio_irq_set_type,
	.flags        = IRQCHIP_SKIP_SET_WAKE,
};

#define PIN_IRQ_PENDING	(BIT(INTERRUPT_STS_OFF) | BIT(WAKE_STS_OFF))

static irqreturn_t amd_gpio_irq_handler(int irq, void *dev_id)
{
	struct amd_gpio *gpio_dev = dev_id;
	struct gpio_chip *gc = &gpio_dev->gc;
	irqreturn_t ret = IRQ_NONE;
	unsigned int i, irqnr;
	unsigned long flags;
	u32 *regs, regval;
	u64 status, mask;

	/* Read the wake status */
	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
	status = readl(gpio_dev->base + WAKE_INT_STATUS_REG1);
	status <<= 32;
	status |= readl(gpio_dev->base + WAKE_INT_STATUS_REG0);
	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);

	/* Bit 0-45 contain the relevant status bits */
	status &= (1ULL << 46) - 1;
	regs = gpio_dev->base;
	for (mask = 1, irqnr = 0; status; mask <<= 1, regs += 4, irqnr += 4) {
		if (!(status & mask))
			continue;
		status &= ~mask;

		/* Each status bit covers four pins */
		for (i = 0; i < 4; i++) {
			regval = readl(regs + i);
			if (!(regval & PIN_IRQ_PENDING) ||
			    !(regval & BIT(INTERRUPT_MASK_OFF)))
				continue;
			irq = irq_find_mapping(gc->irq.domain, irqnr + i);
			generic_handle_irq(irq);

			/* Clear interrupt.
			 * We must read the pin register again, in case the
			 * value was changed while executing
			 * generic_handle_irq() above.
			 */
			raw_spin_lock_irqsave(&gpio_dev->lock, flags);
			regval = readl(regs + i);
			writel(regval, regs + i);
			raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
			ret = IRQ_HANDLED;
		}
	}

	/* Signal EOI to the GPIO unit */
	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
	regval = readl(gpio_dev->base + WAKE_INT_MASTER_REG);
	regval |= EOI_MASK;
	writel(regval, gpio_dev->base + WAKE_INT_MASTER_REG);
	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);

	return ret;
}

static int amd_get_groups_count(struct pinctrl_dev *pctldev)
{
	struct amd_gpio *gpio_dev = pinctrl_dev_get_drvdata(pctldev);

	return gpio_dev->ngroups;
}

static const char *amd_get_group_name(struct pinctrl_dev *pctldev,
				      unsigned group)
{
	struct amd_gpio *gpio_dev = pinctrl_dev_get_drvdata(pctldev);

	return gpio_dev->groups[group].name;
}

static int amd_get_group_pins(struct pinctrl_dev *pctldev,
			      unsigned group,
			      const unsigned **pins,
			      unsigned *num_pins)
{
	struct amd_gpio *gpio_dev = pinctrl_dev_get_drvdata(pctldev);

	*pins = gpio_dev->groups[group].pins;
	*num_pins = gpio_dev->groups[group].npins;
	return 0;
}

static const struct pinctrl_ops amd_pinctrl_ops = {
	.get_groups_count	= amd_get_groups_count,
	.get_group_name		= amd_get_group_name,
	.get_group_pins		= amd_get_group_pins,
#ifdef CONFIG_OF
	.dt_node_to_map		= pinconf_generic_dt_node_to_map_group,
	.dt_free_map		= pinctrl_utils_free_map,
#endif
};

static int amd_pinconf_get(struct pinctrl_dev *pctldev,
			  unsigned int pin,
			  unsigned long *config)
{
	u32 pin_reg;
	unsigned arg;
	unsigned long flags;
	struct amd_gpio *gpio_dev = pinctrl_dev_get_drvdata(pctldev);
	enum pin_config_param param = pinconf_to_config_param(*config);

	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
	pin_reg = readl(gpio_dev->base + pin*4);
	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);
	switch (param) {
	case PIN_CONFIG_INPUT_DEBOUNCE:
		arg = pin_reg & DB_TMR_OUT_MASK;
		break;

	case PIN_CONFIG_BIAS_PULL_DOWN:
		arg = (pin_reg >> PULL_DOWN_ENABLE_OFF) & BIT(0);
		break;

	case PIN_CONFIG_BIAS_PULL_UP:
		arg = (pin_reg >> PULL_UP_SEL_OFF) & (BIT(0) | BIT(1));
		break;

	case PIN_CONFIG_DRIVE_STRENGTH:
		arg = (pin_reg >> DRV_STRENGTH_SEL_OFF) & DRV_STRENGTH_SEL_MASK;
		break;

	default:
		dev_err(&gpio_dev->pdev->dev, "Invalid config param %04x\n",
			param);
		return -ENOTSUPP;
	}

	*config = pinconf_to_config_packed(param, arg);

	return 0;
}

static int amd_pinconf_set(struct pinctrl_dev *pctldev, unsigned int pin,
				unsigned long *configs, unsigned num_configs)
{
	int i;
	u32 arg;
	int ret = 0;
	u32 pin_reg;
	unsigned long flags;
	enum pin_config_param param;
	struct amd_gpio *gpio_dev = pinctrl_dev_get_drvdata(pctldev);

	raw_spin_lock_irqsave(&gpio_dev->lock, flags);
	for (i = 0; i < num_configs; i++) {
		param = pinconf_to_config_param(configs[i]);
		arg = pinconf_to_config_argument(configs[i]);
		pin_reg = readl(gpio_dev->base + pin*4);

		switch (param) {
		case PIN_CONFIG_INPUT_DEBOUNCE:
			pin_reg &= ~DB_TMR_OUT_MASK;
			pin_reg |= arg & DB_TMR_OUT_MASK;
			break;

		case PIN_CONFIG_BIAS_PULL_DOWN:
			pin_reg &= ~BIT(PULL_DOWN_ENABLE_OFF);
			pin_reg |= (arg & BIT(0)) << PULL_DOWN_ENABLE_OFF;
			break;

		case PIN_CONFIG_BIAS_PULL_UP:
			pin_reg &= ~BIT(PULL_UP_SEL_OFF);
			pin_reg |= (arg & BIT(0)) << PULL_UP_SEL_OFF;
			pin_reg &= ~BIT(PULL_UP_ENABLE_OFF);
			pin_reg |= ((arg>>1) & BIT(0)) << PULL_UP_ENABLE_OFF;
			break;

		case PIN_CONFIG_DRIVE_STRENGTH:
			pin_reg &= ~(DRV_STRENGTH_SEL_MASK
					<< DRV_STRENGTH_SEL_OFF);
			pin_reg |= (arg & DRV_STRENGTH_SEL_MASK)
					<< DRV_STRENGTH_SEL_OFF;
			break;

		default:
			dev_err(&gpio_dev->pdev->dev,
				"Invalid config param %04x\n", param);
			ret = -ENOTSUPP;
		}

		writel(pin_reg, gpio_dev->base + pin*4);
	}
	raw_spin_unlock_irqrestore(&gpio_dev->lock, flags);

	return ret;
}

static int amd_pinconf_group_get(struct pinctrl_dev *pctldev,
				unsigned int group,
				unsigned long *config)
{
	const unsigned *pins;
	unsigned npins;
	int ret;

	ret = amd_get_group_pins(pctldev, group, &pins, &npins);
	if (ret)
		return ret;

	if (amd_pinconf_get(pctldev, pins[0], config))
			return -ENOTSUPP;

	return 0;
}

static int amd_pinconf_group_set(struct pinctrl_dev *pctldev,
				unsigned group, unsigned long *configs,
				unsigned num_configs)
{
	const unsigned *pins;
	unsigned npins;
	int i, ret;

	ret = amd_get_group_pins(pctldev, group, &pins, &npins);
	if (ret)
		return ret;
	for (i = 0; i < npins; i++) {
		if (amd_pinconf_set(pctldev, pins[i], configs, num_configs))
			return -ENOTSUPP;
	}
	return 0;
}

static const struct pinconf_ops amd_pinconf_ops = {
	.pin_config_get		= amd_pinconf_get,
	.pin_config_set		= amd_pinconf_set,
	.pin_config_group_get = amd_pinconf_group_get,
	.pin_config_group_set = amd_pinconf_group_set,
};

#ifdef CONFIG_PM_SLEEP
static bool amd_gpio_should_save(struct amd_gpio *gpio_dev, unsigned int pin)
{
	const struct pin_desc *pd = pin_desc_get(gpio_dev->pctrl, pin);

	if (!pd)
		return false;

	/*
	 * Only restore the pin if it is actually in use by the kernel (or
	 * by userspace).
	 */
	if (pd->mux_owner || pd->gpio_owner ||
	    gpiochip_line_is_irq(&gpio_dev->gc, pin))
		return true;

	return false;
}

static int amd_gpio_suspend(struct device *dev)
{
	struct amd_gpio *gpio_dev = dev_get_drvdata(dev);
	struct pinctrl_desc *desc = gpio_dev->pctrl->desc;
	int i;

	for (i = 0; i < desc->npins; i++) {
		int pin = desc->pins[i].number;

		if (!amd_gpio_should_save(gpio_dev, pin))
			continue;

		gpio_dev->saved_regs[i] = readl(gpio_dev->base + pin*4);
	}

	return 0;
}

static int amd_gpio_resume(struct device *dev)
{
	struct amd_gpio *gpio_dev = dev_get_drvdata(dev);
	struct pinctrl_desc *desc = gpio_dev->pctrl->desc;
	int i;

	for (i = 0; i < desc->npins; i++) {
		int pin = desc->pins[i].number;

		if (!amd_gpio_should_save(gpio_dev, pin))
			continue;

		writel(gpio_dev->saved_regs[i], gpio_dev->base + pin*4);
	}

	return 0;
}

static const struct dev_pm_ops amd_gpio_pm_ops = {
	SET_LATE_SYSTEM_SLEEP_PM_OPS(amd_gpio_suspend,
				     amd_gpio_resume)
};
#endif

static struct pinctrl_desc amd_pinctrl_desc = {
	.pins	= kerncz_pins,
	.npins = ARRAY_SIZE(kerncz_pins),
	.pctlops = &amd_pinctrl_ops,
	.confops = &amd_pinconf_ops,
	.owner = THIS_MODULE,
};

static int amd_gpio_probe(struct platform_device *pdev)
{
	int ret = 0;
	int irq_base;
	struct resource *res;
	struct amd_gpio *gpio_dev;

	gpio_dev = devm_kzalloc(&pdev->dev,
				sizeof(struct amd_gpio), GFP_KERNEL);
	if (!gpio_dev)
		return -ENOMEM;

	raw_spin_lock_init(&gpio_dev->lock);

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res) {
		dev_err(&pdev->dev, "Failed to get gpio io resource.\n");
		return -EINVAL;
	}

	gpio_dev->base = devm_ioremap_nocache(&pdev->dev, res->start,
						resource_size(res));
	if (!gpio_dev->base)
		return -ENOMEM;

	irq_base = platform_get_irq(pdev, 0);
	if (irq_base < 0) {
		dev_err(&pdev->dev, "Failed to get gpio IRQ: %d\n", irq_base);
		return irq_base;
	}

#ifdef CONFIG_PM_SLEEP
	gpio_dev->saved_regs = devm_kcalloc(&pdev->dev, amd_pinctrl_desc.npins,
					    sizeof(*gpio_dev->saved_regs),
					    GFP_KERNEL);
	if (!gpio_dev->saved_regs)
		return -ENOMEM;
#endif

	gpio_dev->pdev = pdev;
	gpio_dev->gc.get_direction	= amd_gpio_get_direction;
	gpio_dev->gc.direction_input	= amd_gpio_direction_input;
	gpio_dev->gc.direction_output	= amd_gpio_direction_output;
	gpio_dev->gc.get			= amd_gpio_get_value;
	gpio_dev->gc.set			= amd_gpio_set_value;
	gpio_dev->gc.set_config		= amd_gpio_set_config;
	gpio_dev->gc.dbg_show		= amd_gpio_dbg_show;

	gpio_dev->gc.base		= -1;
	gpio_dev->gc.label			= pdev->name;
	gpio_dev->gc.owner			= THIS_MODULE;
	gpio_dev->gc.parent			= &pdev->dev;
	gpio_dev->gc.ngpio			= resource_size(res) / 4;
#if defined(CONFIG_OF_GPIO)
	gpio_dev->gc.of_node			= pdev->dev.of_node;
#endif

	gpio_dev->hwbank_num = gpio_dev->gc.ngpio / 64;
	gpio_dev->groups = kerncz_groups;
	gpio_dev->ngroups = ARRAY_SIZE(kerncz_groups);

	amd_pinctrl_desc.name = dev_name(&pdev->dev);
	gpio_dev->pctrl = devm_pinctrl_register(&pdev->dev, &amd_pinctrl_desc,
						gpio_dev);
	if (IS_ERR(gpio_dev->pctrl)) {
		dev_err(&pdev->dev, "Couldn't register pinctrl driver\n");
		return PTR_ERR(gpio_dev->pctrl);
	}

	ret = gpiochip_add_data(&gpio_dev->gc, gpio_dev);
	if (ret)
		return ret;

	ret = gpiochip_add_pin_range(&gpio_dev->gc, dev_name(&pdev->dev),
				0, 0, gpio_dev->gc.ngpio);
	if (ret) {
		dev_err(&pdev->dev, "Failed to add pin range\n");
		goto out2;
	}

	ret = gpiochip_irqchip_add(&gpio_dev->gc,
				&amd_gpio_irqchip,
				0,
				handle_simple_irq,
				IRQ_TYPE_NONE);
	if (ret) {
		dev_err(&pdev->dev, "could not add irqchip\n");
		ret = -ENODEV;
		goto out2;
	}

	ret = devm_request_irq(&pdev->dev, irq_base, amd_gpio_irq_handler,
			       IRQF_SHARED, KBUILD_MODNAME, gpio_dev);
	if (ret)
		goto out2;

	platform_set_drvdata(pdev, gpio_dev);

	dev_dbg(&pdev->dev, "amd gpio driver loaded\n");
	return ret;

out2:
	gpiochip_remove(&gpio_dev->gc);

	return ret;
}

static int amd_gpio_remove(struct platform_device *pdev)
{
	struct amd_gpio *gpio_dev;

	gpio_dev = platform_get_drvdata(pdev);

	gpiochip_remove(&gpio_dev->gc);

	return 0;
}

static const struct acpi_device_id amd_gpio_acpi_match[] = {
	{ "AMD0030", 0 },
	{ "AMDI0030", 0},
	{ },
};
MODULE_DEVICE_TABLE(acpi, amd_gpio_acpi_match);

static struct platform_driver amd_gpio_driver = {
	.driver		= {
		.name	= "amd_gpio",
		.acpi_match_table = ACPI_PTR(amd_gpio_acpi_match),
#ifdef CONFIG_PM_SLEEP
		.pm	= &amd_gpio_pm_ops,
#endif
	},
	.probe		= amd_gpio_probe,
	.remove		= amd_gpio_remove,
};

module_platform_driver(amd_gpio_driver);

MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Ken Xue <Ken.Xue@amd.com>, Jeff Wu <Jeff.Wu@amd.com>");
MODULE_DESCRIPTION("AMD GPIO pinctrl driver");