summaryrefslogtreecommitdiffstats
path: root/drivers/gpio/gpio-zynq.c
blob: 3f5fcdd5a4291dd41c35e5032122a4b39873686d (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
/*
 * Xilinx Zynq GPIO device driver
 *
 * Copyright (C) 2009 - 2014 Xilinx, Inc.
 *
 * This program is free software; you can redistribute it and/or modify it under
 * the terms of the GNU General Public License as published by the Free Software
 * Foundation; either version 2 of the License, or (at your option) any later
 * version.
 */

#include <linux/bitops.h>
#include <linux/clk.h>
#include <linux/gpio/driver.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/of.h>

#define DRIVER_NAME "zynq-gpio"

/* Maximum banks */
#define ZYNQ_GPIO_MAX_BANK	4
#define ZYNQMP_GPIO_MAX_BANK	6

#define ZYNQ_GPIO_BANK0_NGPIO	32
#define ZYNQ_GPIO_BANK1_NGPIO	22
#define ZYNQ_GPIO_BANK2_NGPIO	32
#define ZYNQ_GPIO_BANK3_NGPIO	32

#define ZYNQMP_GPIO_BANK0_NGPIO 26
#define ZYNQMP_GPIO_BANK1_NGPIO 26
#define ZYNQMP_GPIO_BANK2_NGPIO 26
#define ZYNQMP_GPIO_BANK3_NGPIO 32
#define ZYNQMP_GPIO_BANK4_NGPIO 32
#define ZYNQMP_GPIO_BANK5_NGPIO 32

#define	ZYNQ_GPIO_NR_GPIOS	118
#define	ZYNQMP_GPIO_NR_GPIOS	174

#define ZYNQ_GPIO_BANK0_PIN_MIN(str)	0
#define ZYNQ_GPIO_BANK0_PIN_MAX(str)	(ZYNQ_GPIO_BANK0_PIN_MIN(str) + \
					ZYNQ##str##_GPIO_BANK0_NGPIO - 1)
#define ZYNQ_GPIO_BANK1_PIN_MIN(str)	(ZYNQ_GPIO_BANK0_PIN_MAX(str) + 1)
#define ZYNQ_GPIO_BANK1_PIN_MAX(str)	(ZYNQ_GPIO_BANK1_PIN_MIN(str) + \
					ZYNQ##str##_GPIO_BANK1_NGPIO - 1)
#define ZYNQ_GPIO_BANK2_PIN_MIN(str)	(ZYNQ_GPIO_BANK1_PIN_MAX(str) + 1)
#define ZYNQ_GPIO_BANK2_PIN_MAX(str)	(ZYNQ_GPIO_BANK2_PIN_MIN(str) + \
					ZYNQ##str##_GPIO_BANK2_NGPIO - 1)
#define ZYNQ_GPIO_BANK3_PIN_MIN(str)	(ZYNQ_GPIO_BANK2_PIN_MAX(str) + 1)
#define ZYNQ_GPIO_BANK3_PIN_MAX(str)	(ZYNQ_GPIO_BANK3_PIN_MIN(str) + \
					ZYNQ##str##_GPIO_BANK3_NGPIO - 1)
#define ZYNQ_GPIO_BANK4_PIN_MIN(str)	(ZYNQ_GPIO_BANK3_PIN_MAX(str) + 1)
#define ZYNQ_GPIO_BANK4_PIN_MAX(str)	(ZYNQ_GPIO_BANK4_PIN_MIN(str) + \
					ZYNQ##str##_GPIO_BANK4_NGPIO - 1)
#define ZYNQ_GPIO_BANK5_PIN_MIN(str)	(ZYNQ_GPIO_BANK4_PIN_MAX(str) + 1)
#define ZYNQ_GPIO_BANK5_PIN_MAX(str)	(ZYNQ_GPIO_BANK5_PIN_MIN(str) + \
					ZYNQ##str##_GPIO_BANK5_NGPIO - 1)

/* Register offsets for the GPIO device */
/* LSW Mask & Data -WO */
#define ZYNQ_GPIO_DATA_LSW_OFFSET(BANK)	(0x000 + (8 * BANK))
/* MSW Mask & Data -WO */
#define ZYNQ_GPIO_DATA_MSW_OFFSET(BANK)	(0x004 + (8 * BANK))
/* Data Register-RW */
#define ZYNQ_GPIO_DATA_OFFSET(BANK)	(0x040 + (4 * BANK))
#define ZYNQ_GPIO_DATA_RO_OFFSET(BANK)	(0x060 + (4 * BANK))
/* Direction mode reg-RW */
#define ZYNQ_GPIO_DIRM_OFFSET(BANK)	(0x204 + (0x40 * BANK))
/* Output enable reg-RW */
#define ZYNQ_GPIO_OUTEN_OFFSET(BANK)	(0x208 + (0x40 * BANK))
/* Interrupt mask reg-RO */
#define ZYNQ_GPIO_INTMASK_OFFSET(BANK)	(0x20C + (0x40 * BANK))
/* Interrupt enable reg-WO */
#define ZYNQ_GPIO_INTEN_OFFSET(BANK)	(0x210 + (0x40 * BANK))
/* Interrupt disable reg-WO */
#define ZYNQ_GPIO_INTDIS_OFFSET(BANK)	(0x214 + (0x40 * BANK))
/* Interrupt status reg-RO */
#define ZYNQ_GPIO_INTSTS_OFFSET(BANK)	(0x218 + (0x40 * BANK))
/* Interrupt type reg-RW */
#define ZYNQ_GPIO_INTTYPE_OFFSET(BANK)	(0x21C + (0x40 * BANK))
/* Interrupt polarity reg-RW */
#define ZYNQ_GPIO_INTPOL_OFFSET(BANK)	(0x220 + (0x40 * BANK))
/* Interrupt on any, reg-RW */
#define ZYNQ_GPIO_INTANY_OFFSET(BANK)	(0x224 + (0x40 * BANK))

/* Disable all interrupts mask */
#define ZYNQ_GPIO_IXR_DISABLE_ALL	0xFFFFFFFF

/* Mid pin number of a bank */
#define ZYNQ_GPIO_MID_PIN_NUM 16

/* GPIO upper 16 bit mask */
#define ZYNQ_GPIO_UPPER_MASK 0xFFFF0000

/* set to differentiate zynq from zynqmp, 0=zynqmp, 1=zynq */
#define ZYNQ_GPIO_QUIRK_IS_ZYNQ	BIT(0)
#define GPIO_QUIRK_DATA_RO_BUG	BIT(1)

struct gpio_regs {
	u32 datamsw[ZYNQMP_GPIO_MAX_BANK];
	u32 datalsw[ZYNQMP_GPIO_MAX_BANK];
	u32 dirm[ZYNQMP_GPIO_MAX_BANK];
	u32 outen[ZYNQMP_GPIO_MAX_BANK];
	u32 int_en[ZYNQMP_GPIO_MAX_BANK];
	u32 int_dis[ZYNQMP_GPIO_MAX_BANK];
	u32 int_type[ZYNQMP_GPIO_MAX_BANK];
	u32 int_polarity[ZYNQMP_GPIO_MAX_BANK];
	u32 int_any[ZYNQMP_GPIO_MAX_BANK];
};

/**
 * struct zynq_gpio - gpio device private data structure
 * @chip:	instance of the gpio_chip
 * @base_addr:	base address of the GPIO device
 * @clk:	clock resource for this controller
 * @irq:	interrupt for the GPIO device
 * @p_data:	pointer to platform data
 * @context:	context registers
 */
struct zynq_gpio {
	struct gpio_chip chip;
	void __iomem *base_addr;
	struct clk *clk;
	int irq;
	const struct zynq_platform_data *p_data;
	struct gpio_regs context;
};

/**
 * struct zynq_platform_data -  zynq gpio platform data structure
 * @label:	string to store in gpio->label
 * @quirks:	Flags is used to identify the platform
 * @ngpio:	max number of gpio pins
 * @max_bank:	maximum number of gpio banks
 * @bank_min:	this array represents bank's min pin
 * @bank_max:	this array represents bank's max pin
 */
struct zynq_platform_data {
	const char *label;
	u32 quirks;
	u16 ngpio;
	int max_bank;
	int bank_min[ZYNQMP_GPIO_MAX_BANK];
	int bank_max[ZYNQMP_GPIO_MAX_BANK];
};

static struct irq_chip zynq_gpio_level_irqchip;
static struct irq_chip zynq_gpio_edge_irqchip;

/**
 * zynq_gpio_is_zynq - test if HW is zynq or zynqmp
 * @gpio:	Pointer to driver data struct
 *
 * Return: 0 if zynqmp, 1 if zynq.
 */
static int zynq_gpio_is_zynq(struct zynq_gpio *gpio)
{
	return !!(gpio->p_data->quirks & ZYNQ_GPIO_QUIRK_IS_ZYNQ);
}

/**
 * gpio_data_ro_bug - test if HW bug exists or not
 * @gpio:       Pointer to driver data struct
 *
 * Return: 0 if bug doesnot exist, 1 if bug exists.
 */
static int gpio_data_ro_bug(struct zynq_gpio *gpio)
{
	return !!(gpio->p_data->quirks & GPIO_QUIRK_DATA_RO_BUG);
}

/**
 * zynq_gpio_get_bank_pin - Get the bank number and pin number within that bank
 * for a given pin in the GPIO device
 * @pin_num:	gpio pin number within the device
 * @bank_num:	an output parameter used to return the bank number of the gpio
 *		pin
 * @bank_pin_num: an output parameter used to return pin number within a bank
 *		  for the given gpio pin
 * @gpio:	gpio device data structure
 *
 * Returns the bank number and pin offset within the bank.
 */
static inline void zynq_gpio_get_bank_pin(unsigned int pin_num,
					  unsigned int *bank_num,
					  unsigned int *bank_pin_num,
					  struct zynq_gpio *gpio)
{
	int bank;

	for (bank = 0; bank < gpio->p_data->max_bank; bank++) {
		if ((pin_num >= gpio->p_data->bank_min[bank]) &&
		    (pin_num <= gpio->p_data->bank_max[bank])) {
			*bank_num = bank;
			*bank_pin_num = pin_num -
					gpio->p_data->bank_min[bank];
			return;
		}
	}

	/* default */
	WARN(true, "invalid GPIO pin number: %u", pin_num);
	*bank_num = 0;
	*bank_pin_num = 0;
}

/**
 * zynq_gpio_get_value - Get the state of the specified pin of GPIO device
 * @chip:	gpio_chip instance to be worked on
 * @pin:	gpio pin number within the device
 *
 * This function reads the state of the specified pin of the GPIO device.
 *
 * Return: 0 if the pin is low, 1 if pin is high.
 */
static int zynq_gpio_get_value(struct gpio_chip *chip, unsigned int pin)
{
	u32 data;
	unsigned int bank_num, bank_pin_num;
	struct zynq_gpio *gpio = gpiochip_get_data(chip);

	zynq_gpio_get_bank_pin(pin, &bank_num, &bank_pin_num, gpio);

	if (gpio_data_ro_bug(gpio)) {
		if (zynq_gpio_is_zynq(gpio)) {
			if (bank_num <= 1) {
				data = readl_relaxed(gpio->base_addr +
					ZYNQ_GPIO_DATA_RO_OFFSET(bank_num));
			} else {
				data = readl_relaxed(gpio->base_addr +
					ZYNQ_GPIO_DATA_OFFSET(bank_num));
			}
		} else {
			if (bank_num <= 2) {
				data = readl_relaxed(gpio->base_addr +
					ZYNQ_GPIO_DATA_RO_OFFSET(bank_num));
			} else {
				data = readl_relaxed(gpio->base_addr +
					ZYNQ_GPIO_DATA_OFFSET(bank_num));
			}
		}
	} else {
		data = readl_relaxed(gpio->base_addr +
			ZYNQ_GPIO_DATA_RO_OFFSET(bank_num));
	}
	return (data >> bank_pin_num) & 1;
}

/**
 * zynq_gpio_set_value - Modify the state of the pin with specified value
 * @chip:	gpio_chip instance to be worked on
 * @pin:	gpio pin number within the device
 * @state:	value used to modify the state of the specified pin
 *
 * This function calculates the register offset (i.e to lower 16 bits or
 * upper 16 bits) based on the given pin number and sets the state of a
 * gpio pin to the specified value. The state is either 0 or non-zero.
 */
static void zynq_gpio_set_value(struct gpio_chip *chip, unsigned int pin,
				int state)
{
	unsigned int reg_offset, bank_num, bank_pin_num;
	struct zynq_gpio *gpio = gpiochip_get_data(chip);

	zynq_gpio_get_bank_pin(pin, &bank_num, &bank_pin_num, gpio);

	if (bank_pin_num >= ZYNQ_GPIO_MID_PIN_NUM) {
		/* only 16 data bits in bit maskable reg */
		bank_pin_num -= ZYNQ_GPIO_MID_PIN_NUM;
		reg_offset = ZYNQ_GPIO_DATA_MSW_OFFSET(bank_num);
	} else {
		reg_offset = ZYNQ_GPIO_DATA_LSW_OFFSET(bank_num);
	}

	/*
	 * get the 32 bit value to be written to the mask/data register where
	 * the upper 16 bits is the mask and lower 16 bits is the data
	 */
	state = !!state;
	state = ~(1 << (bank_pin_num + ZYNQ_GPIO_MID_PIN_NUM)) &
		((state << bank_pin_num) | ZYNQ_GPIO_UPPER_MASK);

	writel_relaxed(state, gpio->base_addr + reg_offset);
}

/**
 * zynq_gpio_dir_in - Set the direction of the specified GPIO pin as input
 * @chip:	gpio_chip instance to be worked on
 * @pin:	gpio pin number within the device
 *
 * This function uses the read-modify-write sequence to set the direction of
 * the gpio pin as input.
 *
 * Return: 0 always
 */
static int zynq_gpio_dir_in(struct gpio_chip *chip, unsigned int pin)
{
	u32 reg;
	unsigned int bank_num, bank_pin_num;
	struct zynq_gpio *gpio = gpiochip_get_data(chip);

	zynq_gpio_get_bank_pin(pin, &bank_num, &bank_pin_num, gpio);

	/*
	 * On zynq bank 0 pins 7 and 8 are special and cannot be used
	 * as inputs.
	 */
	if (zynq_gpio_is_zynq(gpio) && bank_num == 0 &&
	    (bank_pin_num == 7 || bank_pin_num == 8))
		return -EINVAL;

	/* clear the bit in direction mode reg to set the pin as input */
	reg = readl_relaxed(gpio->base_addr + ZYNQ_GPIO_DIRM_OFFSET(bank_num));
	reg &= ~BIT(bank_pin_num);
	writel_relaxed(reg, gpio->base_addr + ZYNQ_GPIO_DIRM_OFFSET(bank_num));

	return 0;
}

/**
 * zynq_gpio_dir_out - Set the direction of the specified GPIO pin as output
 * @chip:	gpio_chip instance to be worked on
 * @pin:	gpio pin number within the device
 * @state:	value to be written to specified pin
 *
 * This function sets the direction of specified GPIO pin as output, configures
 * the Output Enable register for the pin and uses zynq_gpio_set to set
 * the state of the pin to the value specified.
 *
 * Return: 0 always
 */
static int zynq_gpio_dir_out(struct gpio_chip *chip, unsigned int pin,
			     int state)
{
	u32 reg;
	unsigned int bank_num, bank_pin_num;
	struct zynq_gpio *gpio = gpiochip_get_data(chip);

	zynq_gpio_get_bank_pin(pin, &bank_num, &bank_pin_num, gpio);

	/* set the GPIO pin as output */
	reg = readl_relaxed(gpio->base_addr + ZYNQ_GPIO_DIRM_OFFSET(bank_num));
	reg |= BIT(bank_pin_num);
	writel_relaxed(reg, gpio->base_addr + ZYNQ_GPIO_DIRM_OFFSET(bank_num));

	/* configure the output enable reg for the pin */
	reg = readl_relaxed(gpio->base_addr + ZYNQ_GPIO_OUTEN_OFFSET(bank_num));
	reg |= BIT(bank_pin_num);
	writel_relaxed(reg, gpio->base_addr + ZYNQ_GPIO_OUTEN_OFFSET(bank_num));

	/* set the state of the pin */
	zynq_gpio_set_value(chip, pin, state);
	return 0;
}

/**
 * zynq_gpio_irq_mask - Disable the interrupts for a gpio pin
 * @irq_data:	per irq and chip data passed down to chip functions
 *
 * This function calculates gpio pin number from irq number and sets the
 * bit in the Interrupt Disable register of the corresponding bank to disable
 * interrupts for that pin.
 */
static void zynq_gpio_irq_mask(struct irq_data *irq_data)
{
	unsigned int device_pin_num, bank_num, bank_pin_num;
	struct zynq_gpio *gpio =
		gpiochip_get_data(irq_data_get_irq_chip_data(irq_data));

	device_pin_num = irq_data->hwirq;
	zynq_gpio_get_bank_pin(device_pin_num, &bank_num, &bank_pin_num, gpio);
	writel_relaxed(BIT(bank_pin_num),
		       gpio->base_addr + ZYNQ_GPIO_INTDIS_OFFSET(bank_num));
}

/**
 * zynq_gpio_irq_unmask - Enable the interrupts for a gpio pin
 * @irq_data:	irq data containing irq number of gpio pin for the interrupt
 *		to enable
 *
 * This function calculates the gpio pin number from irq number and sets the
 * bit in the Interrupt Enable register of the corresponding bank to enable
 * interrupts for that pin.
 */
static void zynq_gpio_irq_unmask(struct irq_data *irq_data)
{
	unsigned int device_pin_num, bank_num, bank_pin_num;
	struct zynq_gpio *gpio =
		gpiochip_get_data(irq_data_get_irq_chip_data(irq_data));

	device_pin_num = irq_data->hwirq;
	zynq_gpio_get_bank_pin(device_pin_num, &bank_num, &bank_pin_num, gpio);
	writel_relaxed(BIT(bank_pin_num),
		       gpio->base_addr + ZYNQ_GPIO_INTEN_OFFSET(bank_num));
}

/**
 * zynq_gpio_irq_ack - Acknowledge the interrupt of a gpio pin
 * @irq_data:	irq data containing irq number of gpio pin for the interrupt
 *		to ack
 *
 * This function calculates gpio pin number from irq number and sets the bit
 * in the Interrupt Status Register of the corresponding bank, to ACK the irq.
 */
static void zynq_gpio_irq_ack(struct irq_data *irq_data)
{
	unsigned int device_pin_num, bank_num, bank_pin_num;
	struct zynq_gpio *gpio =
		gpiochip_get_data(irq_data_get_irq_chip_data(irq_data));

	device_pin_num = irq_data->hwirq;
	zynq_gpio_get_bank_pin(device_pin_num, &bank_num, &bank_pin_num, gpio);
	writel_relaxed(BIT(bank_pin_num),
		       gpio->base_addr + ZYNQ_GPIO_INTSTS_OFFSET(bank_num));
}

/**
 * zynq_gpio_irq_enable - Enable the interrupts for a gpio pin
 * @irq_data:	irq data containing irq number of gpio pin for the interrupt
 *		to enable
 *
 * Clears the INTSTS bit and unmasks the given interrupt.
 */
static void zynq_gpio_irq_enable(struct irq_data *irq_data)
{
	/*
	 * The Zynq GPIO controller does not disable interrupt detection when
	 * the interrupt is masked and only disables the propagation of the
	 * interrupt. This means when the controller detects an interrupt
	 * condition while the interrupt is logically disabled it will propagate
	 * that interrupt event once the interrupt is enabled. This will cause
	 * the interrupt consumer to see spurious interrupts to prevent this
	 * first make sure that the interrupt is not asserted and then enable
	 * it.
	 */
	zynq_gpio_irq_ack(irq_data);
	zynq_gpio_irq_unmask(irq_data);
}

/**
 * zynq_gpio_set_irq_type - Set the irq type for a gpio pin
 * @irq_data:	irq data containing irq number of gpio pin
 * @type:	interrupt type that is to be set for the gpio pin
 *
 * This function gets the gpio pin number and its bank from the gpio pin number
 * and configures the INT_TYPE, INT_POLARITY and INT_ANY registers.
 *
 * Return: 0, negative error otherwise.
 * TYPE-EDGE_RISING,  INT_TYPE - 1, INT_POLARITY - 1,  INT_ANY - 0;
 * TYPE-EDGE_FALLING, INT_TYPE - 1, INT_POLARITY - 0,  INT_ANY - 0;
 * TYPE-EDGE_BOTH,    INT_TYPE - 1, INT_POLARITY - NA, INT_ANY - 1;
 * TYPE-LEVEL_HIGH,   INT_TYPE - 0, INT_POLARITY - 1,  INT_ANY - NA;
 * TYPE-LEVEL_LOW,    INT_TYPE - 0, INT_POLARITY - 0,  INT_ANY - NA
 */
static int zynq_gpio_set_irq_type(struct irq_data *irq_data, unsigned int type)
{
	u32 int_type, int_pol, int_any;
	unsigned int device_pin_num, bank_num, bank_pin_num;
	struct zynq_gpio *gpio =
		gpiochip_get_data(irq_data_get_irq_chip_data(irq_data));

	device_pin_num = irq_data->hwirq;
	zynq_gpio_get_bank_pin(device_pin_num, &bank_num, &bank_pin_num, gpio);

	int_type = readl_relaxed(gpio->base_addr +
				 ZYNQ_GPIO_INTTYPE_OFFSET(bank_num));
	int_pol = readl_relaxed(gpio->base_addr +
				ZYNQ_GPIO_INTPOL_OFFSET(bank_num));
	int_any = readl_relaxed(gpio->base_addr +
				ZYNQ_GPIO_INTANY_OFFSET(bank_num));

	/*
	 * based on the type requested, configure the INT_TYPE, INT_POLARITY
	 * and INT_ANY registers
	 */
	switch (type) {
	case IRQ_TYPE_EDGE_RISING:
		int_type |= BIT(bank_pin_num);
		int_pol |= BIT(bank_pin_num);
		int_any &= ~BIT(bank_pin_num);
		break;
	case IRQ_TYPE_EDGE_FALLING:
		int_type |= BIT(bank_pin_num);
		int_pol &= ~BIT(bank_pin_num);
		int_any &= ~BIT(bank_pin_num);
		break;
	case IRQ_TYPE_EDGE_BOTH:
		int_type |= BIT(bank_pin_num);
		int_any |= BIT(bank_pin_num);
		break;
	case IRQ_TYPE_LEVEL_HIGH:
		int_type &= ~BIT(bank_pin_num);
		int_pol |= BIT(bank_pin_num);
		break;
	case IRQ_TYPE_LEVEL_LOW:
		int_type &= ~BIT(bank_pin_num);
		int_pol &= ~BIT(bank_pin_num);
		break;
	default:
		return -EINVAL;
	}

	writel_relaxed(int_type,
		       gpio->base_addr + ZYNQ_GPIO_INTTYPE_OFFSET(bank_num));
	writel_relaxed(int_pol,
		       gpio->base_addr + ZYNQ_GPIO_INTPOL_OFFSET(bank_num));
	writel_relaxed(int_any,
		       gpio->base_addr + ZYNQ_GPIO_INTANY_OFFSET(bank_num));

	if (type & IRQ_TYPE_LEVEL_MASK)
		irq_set_chip_handler_name_locked(irq_data,
						 &zynq_gpio_level_irqchip,
						 handle_fasteoi_irq, NULL);
	else
		irq_set_chip_handler_name_locked(irq_data,
						 &zynq_gpio_edge_irqchip,
						 handle_level_irq, NULL);

	return 0;
}

static int zynq_gpio_set_wake(struct irq_data *data, unsigned int on)
{
	struct zynq_gpio *gpio =
		gpiochip_get_data(irq_data_get_irq_chip_data(data));

	irq_set_irq_wake(gpio->irq, on);

	return 0;
}

/* irq chip descriptor */
static struct irq_chip zynq_gpio_level_irqchip = {
	.name		= DRIVER_NAME,
	.irq_enable	= zynq_gpio_irq_enable,
	.irq_eoi	= zynq_gpio_irq_ack,
	.irq_mask	= zynq_gpio_irq_mask,
	.irq_unmask	= zynq_gpio_irq_unmask,
	.irq_set_type	= zynq_gpio_set_irq_type,
	.irq_set_wake	= zynq_gpio_set_wake,
	.flags		= IRQCHIP_EOI_THREADED | IRQCHIP_EOI_IF_HANDLED |
			  IRQCHIP_MASK_ON_SUSPEND,
};

static struct irq_chip zynq_gpio_edge_irqchip = {
	.name		= DRIVER_NAME,
	.irq_enable	= zynq_gpio_irq_enable,
	.irq_ack	= zynq_gpio_irq_ack,
	.irq_mask	= zynq_gpio_irq_mask,
	.irq_unmask	= zynq_gpio_irq_unmask,
	.irq_set_type	= zynq_gpio_set_irq_type,
	.irq_set_wake	= zynq_gpio_set_wake,
	.flags		= IRQCHIP_MASK_ON_SUSPEND,
};

static void zynq_gpio_handle_bank_irq(struct zynq_gpio *gpio,
				      unsigned int bank_num,
				      unsigned long pending)
{
	unsigned int bank_offset = gpio->p_data->bank_min[bank_num];
	struct irq_domain *irqdomain = gpio->chip.irq.domain;
	int offset;

	if (!pending)
		return;

	for_each_set_bit(offset, &pending, 32) {
		unsigned int gpio_irq;

		gpio_irq = irq_find_mapping(irqdomain, offset + bank_offset);
		generic_handle_irq(gpio_irq);
	}
}

/**
 * zynq_gpio_irqhandler - IRQ handler for the gpio banks of a gpio device
 * @desc:	irq descriptor instance of the 'irq'
 *
 * This function reads the Interrupt Status Register of each bank to get the
 * gpio pin number which has triggered an interrupt. It then acks the triggered
 * interrupt and calls the pin specific handler set by the higher layer
 * application for that pin.
 * Note: A bug is reported if no handler is set for the gpio pin.
 */
static void zynq_gpio_irqhandler(struct irq_desc *desc)
{
	u32 int_sts, int_enb;
	unsigned int bank_num;
	struct zynq_gpio *gpio =
		gpiochip_get_data(irq_desc_get_handler_data(desc));
	struct irq_chip *irqchip = irq_desc_get_chip(desc);

	chained_irq_enter(irqchip, desc);

	for (bank_num = 0; bank_num < gpio->p_data->max_bank; bank_num++) {
		int_sts = readl_relaxed(gpio->base_addr +
					ZYNQ_GPIO_INTSTS_OFFSET(bank_num));
		int_enb = readl_relaxed(gpio->base_addr +
					ZYNQ_GPIO_INTMASK_OFFSET(bank_num));
		zynq_gpio_handle_bank_irq(gpio, bank_num, int_sts & ~int_enb);
	}

	chained_irq_exit(irqchip, desc);
}

static void zynq_gpio_save_context(struct zynq_gpio *gpio)
{
	unsigned int bank_num;

	for (bank_num = 0; bank_num < gpio->p_data->max_bank; bank_num++) {
		gpio->context.datalsw[bank_num] =
				readl_relaxed(gpio->base_addr +
				ZYNQ_GPIO_DATA_LSW_OFFSET(bank_num));
		gpio->context.datamsw[bank_num] =
				readl_relaxed(gpio->base_addr +
				ZYNQ_GPIO_DATA_MSW_OFFSET(bank_num));
		gpio->context.dirm[bank_num] = readl_relaxed(gpio->base_addr +
				ZYNQ_GPIO_DIRM_OFFSET(bank_num));
		gpio->context.int_en[bank_num] = readl_relaxed(gpio->base_addr +
				ZYNQ_GPIO_INTMASK_OFFSET(bank_num));
		gpio->context.int_type[bank_num] =
				readl_relaxed(gpio->base_addr +
				ZYNQ_GPIO_INTTYPE_OFFSET(bank_num));
		gpio->context.int_polarity[bank_num] =
				readl_relaxed(gpio->base_addr +
				ZYNQ_GPIO_INTPOL_OFFSET(bank_num));
		gpio->context.int_any[bank_num] =
				readl_relaxed(gpio->base_addr +
				ZYNQ_GPIO_INTANY_OFFSET(bank_num));
	}
}

static void zynq_gpio_restore_context(struct zynq_gpio *gpio)
{
	unsigned int bank_num;

	for (bank_num = 0; bank_num < gpio->p_data->max_bank; bank_num++) {
		writel_relaxed(gpio->context.datalsw[bank_num],
			       gpio->base_addr +
			       ZYNQ_GPIO_DATA_LSW_OFFSET(bank_num));
		writel_relaxed(gpio->context.datamsw[bank_num],
			       gpio->base_addr +
			       ZYNQ_GPIO_DATA_MSW_OFFSET(bank_num));
		writel_relaxed(gpio->context.dirm[bank_num],
			       gpio->base_addr +
			       ZYNQ_GPIO_DIRM_OFFSET(bank_num));
		writel_relaxed(gpio->context.int_en[bank_num],
			       gpio->base_addr +
			       ZYNQ_GPIO_INTEN_OFFSET(bank_num));
		writel_relaxed(gpio->context.int_type[bank_num],
			       gpio->base_addr +
			       ZYNQ_GPIO_INTTYPE_OFFSET(bank_num));
		writel_relaxed(gpio->context.int_polarity[bank_num],
			       gpio->base_addr +
			       ZYNQ_GPIO_INTPOL_OFFSET(bank_num));
		writel_relaxed(gpio->context.int_any[bank_num],
			       gpio->base_addr +
			       ZYNQ_GPIO_INTANY_OFFSET(bank_num));
	}
}

static int __maybe_unused zynq_gpio_suspend(struct device *dev)
{
	struct zynq_gpio *gpio = dev_get_drvdata(dev);
	struct irq_data *data = irq_get_irq_data(gpio->irq);

	if (!irqd_is_wakeup_set(data)) {
		zynq_gpio_save_context(gpio);
		return pm_runtime_force_suspend(dev);
	}

	return 0;
}

static int __maybe_unused zynq_gpio_resume(struct device *dev)
{
	struct zynq_gpio *gpio = dev_get_drvdata(dev);
	struct irq_data *data = irq_get_irq_data(gpio->irq);
	int ret;

	if (!irqd_is_wakeup_set(data)) {
		ret = pm_runtime_force_resume(dev);
		zynq_gpio_restore_context(gpio);
		return ret;
	}

	return 0;
}

static int __maybe_unused zynq_gpio_runtime_suspend(struct device *dev)
{
	struct platform_device *pdev = to_platform_device(dev);
	struct zynq_gpio *gpio = platform_get_drvdata(pdev);

	clk_disable_unprepare(gpio->clk);

	return 0;
}

static int __maybe_unused zynq_gpio_runtime_resume(struct device *dev)
{
	struct platform_device *pdev = to_platform_device(dev);
	struct zynq_gpio *gpio = platform_get_drvdata(pdev);

	return clk_prepare_enable(gpio->clk);
}

static int zynq_gpio_request(struct gpio_chip *chip, unsigned int offset)
{
	int ret;

	ret = pm_runtime_get_sync(chip->parent);

	/*
	 * If the device is already active pm_runtime_get() will return 1 on
	 * success, but gpio_request still needs to return 0.
	 */
	return ret < 0 ? ret : 0;
}

static void zynq_gpio_free(struct gpio_chip *chip, unsigned int offset)
{
	pm_runtime_put(chip->parent);
}

static const struct dev_pm_ops zynq_gpio_dev_pm_ops = {
	SET_SYSTEM_SLEEP_PM_OPS(zynq_gpio_suspend, zynq_gpio_resume)
	SET_RUNTIME_PM_OPS(zynq_gpio_runtime_suspend,
			   zynq_gpio_runtime_resume, NULL)
};

static const struct zynq_platform_data zynqmp_gpio_def = {
	.label = "zynqmp_gpio",
	.quirks = GPIO_QUIRK_DATA_RO_BUG,
	.ngpio = ZYNQMP_GPIO_NR_GPIOS,
	.max_bank = ZYNQMP_GPIO_MAX_BANK,
	.bank_min[0] = ZYNQ_GPIO_BANK0_PIN_MIN(MP),
	.bank_max[0] = ZYNQ_GPIO_BANK0_PIN_MAX(MP),
	.bank_min[1] = ZYNQ_GPIO_BANK1_PIN_MIN(MP),
	.bank_max[1] = ZYNQ_GPIO_BANK1_PIN_MAX(MP),
	.bank_min[2] = ZYNQ_GPIO_BANK2_PIN_MIN(MP),
	.bank_max[2] = ZYNQ_GPIO_BANK2_PIN_MAX(MP),
	.bank_min[3] = ZYNQ_GPIO_BANK3_PIN_MIN(MP),
	.bank_max[3] = ZYNQ_GPIO_BANK3_PIN_MAX(MP),
	.bank_min[4] = ZYNQ_GPIO_BANK4_PIN_MIN(MP),
	.bank_max[4] = ZYNQ_GPIO_BANK4_PIN_MAX(MP),
	.bank_min[5] = ZYNQ_GPIO_BANK5_PIN_MIN(MP),
	.bank_max[5] = ZYNQ_GPIO_BANK5_PIN_MAX(MP),
};

static const struct zynq_platform_data zynq_gpio_def = {
	.label = "zynq_gpio",
	.quirks = ZYNQ_GPIO_QUIRK_IS_ZYNQ | GPIO_QUIRK_DATA_RO_BUG,
	.ngpio = ZYNQ_GPIO_NR_GPIOS,
	.max_bank = ZYNQ_GPIO_MAX_BANK,
	.bank_min[0] = ZYNQ_GPIO_BANK0_PIN_MIN(),
	.bank_max[0] = ZYNQ_GPIO_BANK0_PIN_MAX(),
	.bank_min[1] = ZYNQ_GPIO_BANK1_PIN_MIN(),
	.bank_max[1] = ZYNQ_GPIO_BANK1_PIN_MAX(),
	.bank_min[2] = ZYNQ_GPIO_BANK2_PIN_MIN(),
	.bank_max[2] = ZYNQ_GPIO_BANK2_PIN_MAX(),
	.bank_min[3] = ZYNQ_GPIO_BANK3_PIN_MIN(),
	.bank_max[3] = ZYNQ_GPIO_BANK3_PIN_MAX(),
};

static const struct of_device_id zynq_gpio_of_match[] = {
	{ .compatible = "xlnx,zynq-gpio-1.0", .data = &zynq_gpio_def },
	{ .compatible = "xlnx,zynqmp-gpio-1.0", .data = &zynqmp_gpio_def },
	{ /* end of table */ }
};
MODULE_DEVICE_TABLE(of, zynq_gpio_of_match);

/**
 * zynq_gpio_probe - Initialization method for a zynq_gpio device
 * @pdev:	platform device instance
 *
 * This function allocates memory resources for the gpio device and registers
 * all the banks of the device. It will also set up interrupts for the gpio
 * pins.
 * Note: Interrupts are disabled for all the banks during initialization.
 *
 * Return: 0 on success, negative error otherwise.
 */
static int zynq_gpio_probe(struct platform_device *pdev)
{
	int ret, bank_num;
	struct zynq_gpio *gpio;
	struct gpio_chip *chip;
	struct resource *res;
	const struct of_device_id *match;

	gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
	if (!gpio)
		return -ENOMEM;

	match = of_match_node(zynq_gpio_of_match, pdev->dev.of_node);
	if (!match) {
		dev_err(&pdev->dev, "of_match_node() failed\n");
		return -EINVAL;
	}
	gpio->p_data = match->data;
	platform_set_drvdata(pdev, gpio);

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	gpio->base_addr = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(gpio->base_addr))
		return PTR_ERR(gpio->base_addr);

	gpio->irq = platform_get_irq(pdev, 0);
	if (gpio->irq < 0) {
		dev_err(&pdev->dev, "invalid IRQ\n");
		return gpio->irq;
	}

	/* configure the gpio chip */
	chip = &gpio->chip;
	chip->label = gpio->p_data->label;
	chip->owner = THIS_MODULE;
	chip->parent = &pdev->dev;
	chip->get = zynq_gpio_get_value;
	chip->set = zynq_gpio_set_value;
	chip->request = zynq_gpio_request;
	chip->free = zynq_gpio_free;
	chip->direction_input = zynq_gpio_dir_in;
	chip->direction_output = zynq_gpio_dir_out;
	chip->base = of_alias_get_id(pdev->dev.of_node, "gpio");
	chip->ngpio = gpio->p_data->ngpio;

	/* Retrieve GPIO clock */
	gpio->clk = devm_clk_get(&pdev->dev, NULL);
	if (IS_ERR(gpio->clk)) {
		dev_err(&pdev->dev, "input clock not found.\n");
		return PTR_ERR(gpio->clk);
	}
	ret = clk_prepare_enable(gpio->clk);
	if (ret) {
		dev_err(&pdev->dev, "Unable to enable clock.\n");
		return ret;
	}

	pm_runtime_set_active(&pdev->dev);
	pm_runtime_enable(&pdev->dev);
	ret = pm_runtime_get_sync(&pdev->dev);
	if (ret < 0)
		goto err_pm_dis;

	/* report a bug if gpio chip registration fails */
	ret = gpiochip_add_data(chip, gpio);
	if (ret) {
		dev_err(&pdev->dev, "Failed to add gpio chip\n");
		goto err_pm_put;
	}

	/* disable interrupts for all banks */
	for (bank_num = 0; bank_num < gpio->p_data->max_bank; bank_num++)
		writel_relaxed(ZYNQ_GPIO_IXR_DISABLE_ALL, gpio->base_addr +
			       ZYNQ_GPIO_INTDIS_OFFSET(bank_num));

	ret = gpiochip_irqchip_add(chip, &zynq_gpio_edge_irqchip, 0,
				   handle_level_irq, IRQ_TYPE_NONE);
	if (ret) {
		dev_err(&pdev->dev, "Failed to add irq chip\n");
		goto err_rm_gpiochip;
	}

	gpiochip_set_chained_irqchip(chip, &zynq_gpio_edge_irqchip, gpio->irq,
				     zynq_gpio_irqhandler);

	pm_runtime_put(&pdev->dev);

	return 0;

err_rm_gpiochip:
	gpiochip_remove(chip);
err_pm_put:
	pm_runtime_put(&pdev->dev);
err_pm_dis:
	pm_runtime_disable(&pdev->dev);
	clk_disable_unprepare(gpio->clk);

	return ret;
}

/**
 * zynq_gpio_remove - Driver removal function
 * @pdev:	platform device instance
 *
 * Return: 0 always
 */
static int zynq_gpio_remove(struct platform_device *pdev)
{
	struct zynq_gpio *gpio = platform_get_drvdata(pdev);

	pm_runtime_get_sync(&pdev->dev);
	gpiochip_remove(&gpio->chip);
	clk_disable_unprepare(gpio->clk);
	device_set_wakeup_capable(&pdev->dev, 0);
	pm_runtime_disable(&pdev->dev);
	return 0;
}

static struct platform_driver zynq_gpio_driver = {
	.driver	= {
		.name = DRIVER_NAME,
		.pm = &zynq_gpio_dev_pm_ops,
		.of_match_table = zynq_gpio_of_match,
	},
	.probe = zynq_gpio_probe,
	.remove = zynq_gpio_remove,
};

/**
 * zynq_gpio_init - Initial driver registration call
 *
 * Return: value from platform_driver_register
 */
static int __init zynq_gpio_init(void)
{
	return platform_driver_register(&zynq_gpio_driver);
}
postcore_initcall(zynq_gpio_init);

static void __exit zynq_gpio_exit(void)
{
	platform_driver_unregister(&zynq_gpio_driver);
}
module_exit(zynq_gpio_exit);

MODULE_AUTHOR("Xilinx Inc.");
MODULE_DESCRIPTION("Zynq GPIO driver");
MODULE_LICENSE("GPL");