summaryrefslogtreecommitdiffstats
path: root/drivers/pinctrl/core.c
blob: 5cdee8669ea35a8221e17c364e50df0d4c90c781 (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
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
/*
 * Core driver for the pin control subsystem
 *
 * Copyright (C) 2011-2012 ST-Ericsson SA
 * Written on behalf of Linaro for ST-Ericsson
 * Based on bits of regulator core, gpio core and clk core
 *
 * Author: Linus Walleij <linus.walleij@linaro.org>
 *
 * Copyright (C) 2012 NVIDIA CORPORATION. All rights reserved.
 *
 * License terms: GNU General Public License (GPL) version 2
 */
#define pr_fmt(fmt) "pinctrl core: " fmt

#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/list.h>
#include <linux/sysfs.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#include <linux/pinctrl/consumer.h>
#include <linux/pinctrl/pinctrl.h>
#include <linux/pinctrl/machine.h>
#include "core.h"
#include "devicetree.h"
#include "pinmux.h"
#include "pinconf.h"

/**
 * struct pinctrl_maps - a list item containing part of the mapping table
 * @node: mapping table list node
 * @maps: array of mapping table entries
 * @num_maps: the number of entries in @maps
 */
struct pinctrl_maps {
	struct list_head node;
	struct pinctrl_map const *maps;
	unsigned num_maps;
};

static bool pinctrl_dummy_state;

/* Mutex taken by all entry points */
DEFINE_MUTEX(pinctrl_mutex);

/* Global list of pin control devices (struct pinctrl_dev) */
LIST_HEAD(pinctrldev_list);

/* List of pin controller handles (struct pinctrl) */
static LIST_HEAD(pinctrl_list);

/* List of pinctrl maps (struct pinctrl_maps) */
static LIST_HEAD(pinctrl_maps);

#define for_each_maps(_maps_node_, _i_, _map_) \
	list_for_each_entry(_maps_node_, &pinctrl_maps, node) \
		for (_i_ = 0, _map_ = &_maps_node_->maps[_i_]; \
			_i_ < _maps_node_->num_maps; \
			_i_++, _map_ = &_maps_node_->maps[_i_])

/**
 * pinctrl_provide_dummies() - indicate if pinctrl provides dummy state support
 *
 * Usually this function is called by platforms without pinctrl driver support
 * but run with some shared drivers using pinctrl APIs.
 * After calling this function, the pinctrl core will return successfully
 * with creating a dummy state for the driver to keep going smoothly.
 */
void pinctrl_provide_dummies(void)
{
	pinctrl_dummy_state = true;
}

const char *pinctrl_dev_get_name(struct pinctrl_dev *pctldev)
{
	/* We're not allowed to register devices without name */
	return pctldev->desc->name;
}
EXPORT_SYMBOL_GPL(pinctrl_dev_get_name);

void *pinctrl_dev_get_drvdata(struct pinctrl_dev *pctldev)
{
	return pctldev->driver_data;
}
EXPORT_SYMBOL_GPL(pinctrl_dev_get_drvdata);

/**
 * get_pinctrl_dev_from_devname() - look up pin controller device
 * @devname: the name of a device instance, as returned by dev_name()
 *
 * Looks up a pin control device matching a certain device name or pure device
 * pointer, the pure device pointer will take precedence.
 */
struct pinctrl_dev *get_pinctrl_dev_from_devname(const char *devname)
{
	struct pinctrl_dev *pctldev = NULL;
	bool found = false;

	if (!devname)
		return NULL;

	list_for_each_entry(pctldev, &pinctrldev_list, node) {
		if (!strcmp(dev_name(pctldev->dev), devname)) {
			/* Matched on device name */
			found = true;
			break;
		}
	}

	return found ? pctldev : NULL;
}

/**
 * pin_get_from_name() - look up a pin number from a name
 * @pctldev: the pin control device to lookup the pin on
 * @name: the name of the pin to look up
 */
int pin_get_from_name(struct pinctrl_dev *pctldev, const char *name)
{
	unsigned i, pin;

	/* The pin number can be retrived from the pin controller descriptor */
	for (i = 0; i < pctldev->desc->npins; i++) {
		struct pin_desc *desc;

		pin = pctldev->desc->pins[i].number;
		desc = pin_desc_get(pctldev, pin);
		/* Pin space may be sparse */
		if (desc == NULL)
			continue;
		if (desc->name && !strcmp(name, desc->name))
			return pin;
	}

	return -EINVAL;
}

/**
 * pin_get_name_from_id() - look up a pin name from a pin id
 * @pctldev: the pin control device to lookup the pin on
 * @name: the name of the pin to look up
 */
const char *pin_get_name(struct pinctrl_dev *pctldev, const unsigned pin)
{
	const struct pin_desc *desc;

	desc = pin_desc_get(pctldev, pin);
	if (desc == NULL) {
		dev_err(pctldev->dev, "failed to get pin(%d) name\n",
			pin);
		return NULL;
	}

	return desc->name;
}

/**
 * pin_is_valid() - check if pin exists on controller
 * @pctldev: the pin control device to check the pin on
 * @pin: pin to check, use the local pin controller index number
 *
 * This tells us whether a certain pin exist on a certain pin controller or
 * not. Pin lists may be sparse, so some pins may not exist.
 */
bool pin_is_valid(struct pinctrl_dev *pctldev, int pin)
{
	struct pin_desc *pindesc;

	if (pin < 0)
		return false;

	mutex_lock(&pinctrl_mutex);
	pindesc = pin_desc_get(pctldev, pin);
	mutex_unlock(&pinctrl_mutex);

	return pindesc != NULL;
}
EXPORT_SYMBOL_GPL(pin_is_valid);

/* Deletes a range of pin descriptors */
static void pinctrl_free_pindescs(struct pinctrl_dev *pctldev,
				  const struct pinctrl_pin_desc *pins,
				  unsigned num_pins)
{
	int i;

	for (i = 0; i < num_pins; i++) {
		struct pin_desc *pindesc;

		pindesc = radix_tree_lookup(&pctldev->pin_desc_tree,
					    pins[i].number);
		if (pindesc != NULL) {
			radix_tree_delete(&pctldev->pin_desc_tree,
					  pins[i].number);
			if (pindesc->dynamic_name)
				kfree(pindesc->name);
		}
		kfree(pindesc);
	}
}

static int pinctrl_register_one_pin(struct pinctrl_dev *pctldev,
				    unsigned number, const char *name)
{
	struct pin_desc *pindesc;

	pindesc = pin_desc_get(pctldev, number);
	if (pindesc != NULL) {
		pr_err("pin %d already registered on %s\n", number,
		       pctldev->desc->name);
		return -EINVAL;
	}

	pindesc = kzalloc(sizeof(*pindesc), GFP_KERNEL);
	if (pindesc == NULL) {
		dev_err(pctldev->dev, "failed to alloc struct pin_desc\n");
		return -ENOMEM;
	}

	/* Set owner */
	pindesc->pctldev = pctldev;

	/* Copy basic pin info */
	if (name) {
		pindesc->name = name;
	} else {
		pindesc->name = kasprintf(GFP_KERNEL, "PIN%u", number);
		if (pindesc->name == NULL) {
			kfree(pindesc);
			return -ENOMEM;
		}
		pindesc->dynamic_name = true;
	}

	radix_tree_insert(&pctldev->pin_desc_tree, number, pindesc);
	pr_debug("registered pin %d (%s) on %s\n",
		 number, pindesc->name, pctldev->desc->name);
	return 0;
}

static int pinctrl_register_pins(struct pinctrl_dev *pctldev,
				 struct pinctrl_pin_desc const *pins,
				 unsigned num_descs)
{
	unsigned i;
	int ret = 0;

	for (i = 0; i < num_descs; i++) {
		ret = pinctrl_register_one_pin(pctldev,
					       pins[i].number, pins[i].name);
		if (ret)
			return ret;
	}

	return 0;
}

/**
 * pinctrl_match_gpio_range() - check if a certain GPIO pin is in range
 * @pctldev: pin controller device to check
 * @gpio: gpio pin to check taken from the global GPIO pin space
 *
 * Tries to match a GPIO pin number to the ranges handled by a certain pin
 * controller, return the range or NULL
 */
static struct pinctrl_gpio_range *
pinctrl_match_gpio_range(struct pinctrl_dev *pctldev, unsigned gpio)
{
	struct pinctrl_gpio_range *range = NULL;

	/* Loop over the ranges */
	list_for_each_entry(range, &pctldev->gpio_ranges, node) {
		/* Check if we're in the valid range */
		if (gpio >= range->base &&
		    gpio < range->base + range->npins) {
			return range;
		}
	}

	return NULL;
}

/**
 * pinctrl_get_device_gpio_range() - find device for GPIO range
 * @gpio: the pin to locate the pin controller for
 * @outdev: the pin control device if found
 * @outrange: the GPIO range if found
 *
 * Find the pin controller handling a certain GPIO pin from the pinspace of
 * the GPIO subsystem, return the device and the matching GPIO range. Returns
 * -EPROBE_DEFER if the GPIO range could not be found in any device since it
 * may still have not been registered.
 */
static int pinctrl_get_device_gpio_range(unsigned gpio,
					 struct pinctrl_dev **outdev,
					 struct pinctrl_gpio_range **outrange)
{
	struct pinctrl_dev *pctldev = NULL;

	/* Loop over the pin controllers */
	list_for_each_entry(pctldev, &pinctrldev_list, node) {
		struct pinctrl_gpio_range *range;

		range = pinctrl_match_gpio_range(pctldev, gpio);
		if (range != NULL) {
			*outdev = pctldev;
			*outrange = range;
			return 0;
		}
	}

	return -EPROBE_DEFER;
}

/**
 * pinctrl_add_gpio_range() - register a GPIO range for a controller
 * @pctldev: pin controller device to add the range to
 * @range: the GPIO range to add
 *
 * This adds a range of GPIOs to be handled by a certain pin controller. Call
 * this to register handled ranges after registering your pin controller.
 */
void pinctrl_add_gpio_range(struct pinctrl_dev *pctldev,
			    struct pinctrl_gpio_range *range)
{
	mutex_lock(&pinctrl_mutex);
	list_add_tail(&range->node, &pctldev->gpio_ranges);
	mutex_unlock(&pinctrl_mutex);
}
EXPORT_SYMBOL_GPL(pinctrl_add_gpio_range);

void pinctrl_add_gpio_ranges(struct pinctrl_dev *pctldev,
			     struct pinctrl_gpio_range *ranges,
			     unsigned nranges)
{
	int i;

	for (i = 0; i < nranges; i++)
		pinctrl_add_gpio_range(pctldev, &ranges[i]);
}
EXPORT_SYMBOL_GPL(pinctrl_add_gpio_ranges);

struct pinctrl_dev *pinctrl_find_and_add_gpio_range(const char *devname,
		struct pinctrl_gpio_range *range)
{
	struct pinctrl_dev *pctldev = get_pinctrl_dev_from_devname(devname);

	/*
	 * If we can't find this device, let's assume that is because
	 * it has not probed yet, so the driver trying to register this
	 * range need to defer probing.
	 */
	if (!pctldev)
		return ERR_PTR(-EPROBE_DEFER);

	pinctrl_add_gpio_range(pctldev, range);
	return pctldev;
}
EXPORT_SYMBOL_GPL(pinctrl_find_and_add_gpio_range);

/**
 * pinctrl_find_gpio_range_from_pin() - locate the GPIO range for a pin
 * @pctldev: the pin controller device to look in
 * @pin: a controller-local number to find the range for
 */
struct pinctrl_gpio_range *
pinctrl_find_gpio_range_from_pin(struct pinctrl_dev *pctldev,
				 unsigned int pin)
{
	struct pinctrl_gpio_range *range = NULL;

	/* Loop over the ranges */
	list_for_each_entry(range, &pctldev->gpio_ranges, node) {
		/* Check if we're in the valid range */
		if (pin >= range->pin_base &&
		    pin < range->pin_base + range->npins) {
			return range;
		}
	}

	return NULL;
}
EXPORT_SYMBOL_GPL(pinctrl_find_gpio_range_from_pin);

/**
 * pinctrl_remove_gpio_range() - remove a range of GPIOs fro a pin controller
 * @pctldev: pin controller device to remove the range from
 * @range: the GPIO range to remove
 */
void pinctrl_remove_gpio_range(struct pinctrl_dev *pctldev,
			       struct pinctrl_gpio_range *range)
{
	mutex_lock(&pinctrl_mutex);
	list_del(&range->node);
	mutex_unlock(&pinctrl_mutex);
}
EXPORT_SYMBOL_GPL(pinctrl_remove_gpio_range);

/**
 * pinctrl_get_group_selector() - returns the group selector for a group
 * @pctldev: the pin controller handling the group
 * @pin_group: the pin group to look up
 */
int pinctrl_get_group_selector(struct pinctrl_dev *pctldev,
			       const char *pin_group)
{
	const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
	unsigned ngroups = pctlops->get_groups_count(pctldev);
	unsigned group_selector = 0;

	while (group_selector < ngroups) {
		const char *gname = pctlops->get_group_name(pctldev,
							    group_selector);
		if (!strcmp(gname, pin_group)) {
			dev_dbg(pctldev->dev,
				"found group selector %u for %s\n",
				group_selector,
				pin_group);
			return group_selector;
		}

		group_selector++;
	}

	dev_err(pctldev->dev, "does not have pin group %s\n",
		pin_group);

	return -EINVAL;
}

/**
 * pinctrl_request_gpio() - request a single pin to be used in as GPIO
 * @gpio: the GPIO pin number from the GPIO subsystem number space
 *
 * This function should *ONLY* be used from gpiolib-based GPIO drivers,
 * as part of their gpio_request() semantics, platforms and individual drivers
 * shall *NOT* request GPIO pins to be muxed in.
 */
int pinctrl_request_gpio(unsigned gpio)
{
	struct pinctrl_dev *pctldev;
	struct pinctrl_gpio_range *range;
	int ret;
	int pin;

	mutex_lock(&pinctrl_mutex);

	ret = pinctrl_get_device_gpio_range(gpio, &pctldev, &range);
	if (ret) {
		mutex_unlock(&pinctrl_mutex);
		return ret;
	}

	/* Convert to the pin controllers number space */
	pin = gpio - range->base + range->pin_base;

	ret = pinmux_request_gpio(pctldev, range, pin, gpio);

	mutex_unlock(&pinctrl_mutex);
	return ret;
}
EXPORT_SYMBOL_GPL(pinctrl_request_gpio);

/**
 * pinctrl_free_gpio() - free control on a single pin, currently used as GPIO
 * @gpio: the GPIO pin number from the GPIO subsystem number space
 *
 * This function should *ONLY* be used from gpiolib-based GPIO drivers,
 * as part of their gpio_free() semantics, platforms and individual drivers
 * shall *NOT* request GPIO pins to be muxed out.
 */
void pinctrl_free_gpio(unsigned gpio)
{
	struct pinctrl_dev *pctldev;
	struct pinctrl_gpio_range *range;
	int ret;
	int pin;

	mutex_lock(&pinctrl_mutex);

	ret = pinctrl_get_device_gpio_range(gpio, &pctldev, &range);
	if (ret) {
		mutex_unlock(&pinctrl_mutex);
		return;
	}

	/* Convert to the pin controllers number space */
	pin = gpio - range->base + range->pin_base;

	pinmux_free_gpio(pctldev, pin, range);

	mutex_unlock(&pinctrl_mutex);
}
EXPORT_SYMBOL_GPL(pinctrl_free_gpio);

static int pinctrl_gpio_direction(unsigned gpio, bool input)
{
	struct pinctrl_dev *pctldev;
	struct pinctrl_gpio_range *range;
	int ret;
	int pin;

	ret = pinctrl_get_device_gpio_range(gpio, &pctldev, &range);
	if (ret)
		return ret;

	/* Convert to the pin controllers number space */
	pin = gpio - range->base + range->pin_base;

	return pinmux_gpio_direction(pctldev, range, pin, input);
}

/**
 * pinctrl_gpio_direction_input() - request a GPIO pin to go into input mode
 * @gpio: the GPIO pin number from the GPIO subsystem number space
 *
 * This function should *ONLY* be used from gpiolib-based GPIO drivers,
 * as part of their gpio_direction_input() semantics, platforms and individual
 * drivers shall *NOT* touch pin control GPIO calls.
 */
int pinctrl_gpio_direction_input(unsigned gpio)
{
	int ret;
	mutex_lock(&pinctrl_mutex);
	ret = pinctrl_gpio_direction(gpio, true);
	mutex_unlock(&pinctrl_mutex);
	return ret;
}
EXPORT_SYMBOL_GPL(pinctrl_gpio_direction_input);

/**
 * pinctrl_gpio_direction_output() - request a GPIO pin to go into output mode
 * @gpio: the GPIO pin number from the GPIO subsystem number space
 *
 * This function should *ONLY* be used from gpiolib-based GPIO drivers,
 * as part of their gpio_direction_output() semantics, platforms and individual
 * drivers shall *NOT* touch pin control GPIO calls.
 */
int pinctrl_gpio_direction_output(unsigned gpio)
{
	int ret;
	mutex_lock(&pinctrl_mutex);
	ret = pinctrl_gpio_direction(gpio, false);
	mutex_unlock(&pinctrl_mutex);
	return ret;
}
EXPORT_SYMBOL_GPL(pinctrl_gpio_direction_output);

static struct pinctrl_state *find_state(struct pinctrl *p,
					const char *name)
{
	struct pinctrl_state *state;

	list_for_each_entry(state, &p->states, node)
		if (!strcmp(state->name, name))
			return state;

	return NULL;
}

static struct pinctrl_state *create_state(struct pinctrl *p,
					  const char *name)
{
	struct pinctrl_state *state;

	state = kzalloc(sizeof(*state), GFP_KERNEL);
	if (state == NULL) {
		dev_err(p->dev,
			"failed to alloc struct pinctrl_state\n");
		return ERR_PTR(-ENOMEM);
	}

	state->name = name;
	INIT_LIST_HEAD(&state->settings);

	list_add_tail(&state->node, &p->states);

	return state;
}

static int add_setting(struct pinctrl *p, struct pinctrl_map const *map)
{
	struct pinctrl_state *state;
	struct pinctrl_setting *setting;
	int ret;

	state = find_state(p, map->name);
	if (!state)
		state = create_state(p, map->name);
	if (IS_ERR(state))
		return PTR_ERR(state);

	if (map->type == PIN_MAP_TYPE_DUMMY_STATE)
		return 0;

	setting = kzalloc(sizeof(*setting), GFP_KERNEL);
	if (setting == NULL) {
		dev_err(p->dev,
			"failed to alloc struct pinctrl_setting\n");
		return -ENOMEM;
	}

	setting->type = map->type;

	setting->pctldev = get_pinctrl_dev_from_devname(map->ctrl_dev_name);
	if (setting->pctldev == NULL) {
		dev_info(p->dev, "unknown pinctrl device %s in map entry, deferring probe",
			map->ctrl_dev_name);
		kfree(setting);
		/*
		 * OK let us guess that the driver is not there yet, and
		 * let's defer obtaining this pinctrl handle to later...
		 */
		return -EPROBE_DEFER;
	}

	setting->dev_name = map->dev_name;

	switch (map->type) {
	case PIN_MAP_TYPE_MUX_GROUP:
		ret = pinmux_map_to_setting(map, setting);
		break;
	case PIN_MAP_TYPE_CONFIGS_PIN:
	case PIN_MAP_TYPE_CONFIGS_GROUP:
		ret = pinconf_map_to_setting(map, setting);
		break;
	default:
		ret = -EINVAL;
		break;
	}
	if (ret < 0) {
		kfree(setting);
		return ret;
	}

	list_add_tail(&setting->node, &state->settings);

	return 0;
}

static struct pinctrl *find_pinctrl(struct device *dev)
{
	struct pinctrl *p;

	list_for_each_entry(p, &pinctrl_list, node)
		if (p->dev == dev)
			return p;

	return NULL;
}

static void pinctrl_put_locked(struct pinctrl *p, bool inlist);

static struct pinctrl *create_pinctrl(struct device *dev)
{
	struct pinctrl *p;
	const char *devname;
	struct pinctrl_maps *maps_node;
	int i;
	struct pinctrl_map const *map;
	int ret;

	/*
	 * create the state cookie holder struct pinctrl for each
	 * mapping, this is what consumers will get when requesting
	 * a pin control handle with pinctrl_get()
	 */
	p = kzalloc(sizeof(*p), GFP_KERNEL);
	if (p == NULL) {
		dev_err(dev, "failed to alloc struct pinctrl\n");
		return ERR_PTR(-ENOMEM);
	}
	p->dev = dev;
	INIT_LIST_HEAD(&p->states);
	INIT_LIST_HEAD(&p->dt_maps);

	ret = pinctrl_dt_to_map(p);
	if (ret < 0) {
		kfree(p);
		return ERR_PTR(ret);
	}

	devname = dev_name(dev);

	/* Iterate over the pin control maps to locate the right ones */
	for_each_maps(maps_node, i, map) {
		/* Map must be for this device */
		if (strcmp(map->dev_name, devname))
			continue;

		ret = add_setting(p, map);
		if (ret < 0) {
			pinctrl_put_locked(p, false);
			return ERR_PTR(ret);
		}
	}

	/* Add the pinmux to the global list */
	list_add_tail(&p->node, &pinctrl_list);

	return p;
}

static struct pinctrl *pinctrl_get_locked(struct device *dev)
{
	struct pinctrl *p;

	if (WARN_ON(!dev))
		return ERR_PTR(-EINVAL);

	p = find_pinctrl(dev);
	if (p != NULL)
		return ERR_PTR(-EBUSY);

	return create_pinctrl(dev);
}

/**
 * pinctrl_get() - retrieves the pinctrl handle for a device
 * @dev: the device to obtain the handle for
 */
struct pinctrl *pinctrl_get(struct device *dev)
{
	struct pinctrl *p;

	mutex_lock(&pinctrl_mutex);
	p = pinctrl_get_locked(dev);
	mutex_unlock(&pinctrl_mutex);

	return p;
}
EXPORT_SYMBOL_GPL(pinctrl_get);

static void pinctrl_put_locked(struct pinctrl *p, bool inlist)
{
	struct pinctrl_state *state, *n1;
	struct pinctrl_setting *setting, *n2;

	list_for_each_entry_safe(state, n1, &p->states, node) {
		list_for_each_entry_safe(setting, n2, &state->settings, node) {
			switch (setting->type) {
			case PIN_MAP_TYPE_MUX_GROUP:
				if (state == p->state)
					pinmux_disable_setting(setting);
				pinmux_free_setting(setting);
				break;
			case PIN_MAP_TYPE_CONFIGS_PIN:
			case PIN_MAP_TYPE_CONFIGS_GROUP:
				pinconf_free_setting(setting);
				break;
			default:
				break;
			}
			list_del(&setting->node);
			kfree(setting);
		}
		list_del(&state->node);
		kfree(state);
	}

	pinctrl_dt_free_maps(p);

	if (inlist)
		list_del(&p->node);
	kfree(p);
}

/**
 * pinctrl_put() - release a previously claimed pinctrl handle
 * @p: the pinctrl handle to release
 */
void pinctrl_put(struct pinctrl *p)
{
	mutex_lock(&pinctrl_mutex);
	pinctrl_put_locked(p, true);
	mutex_unlock(&pinctrl_mutex);
}
EXPORT_SYMBOL_GPL(pinctrl_put);

static struct pinctrl_state *pinctrl_lookup_state_locked(struct pinctrl *p,
							 const char *name)
{
	struct pinctrl_state *state;

	state = find_state(p, name);
	if (!state) {
		if (pinctrl_dummy_state) {
			/* create dummy state */
			dev_dbg(p->dev, "using pinctrl dummy state (%s)\n",
				name);
			state = create_state(p, name);
		} else
			state = ERR_PTR(-ENODEV);
	}

	return state;
}

/**
 * pinctrl_lookup_state() - retrieves a state handle from a pinctrl handle
 * @p: the pinctrl handle to retrieve the state from
 * @name: the state name to retrieve
 */
struct pinctrl_state *pinctrl_lookup_state(struct pinctrl *p, const char *name)
{
	struct pinctrl_state *s;

	mutex_lock(&pinctrl_mutex);
	s = pinctrl_lookup_state_locked(p, name);
	mutex_unlock(&pinctrl_mutex);

	return s;
}
EXPORT_SYMBOL_GPL(pinctrl_lookup_state);

static int pinctrl_select_state_locked(struct pinctrl *p,
				       struct pinctrl_state *state)
{
	struct pinctrl_setting *setting, *setting2;
	int ret;

	if (p->state == state)
		return 0;

	if (p->state) {
		/*
		 * The set of groups with a mux configuration in the old state
		 * may not be identical to the set of groups with a mux setting
		 * in the new state. While this might be unusual, it's entirely
		 * possible for the "user"-supplied mapping table to be written
		 * that way. For each group that was configured in the old state
		 * but not in the new state, this code puts that group into a
		 * safe/disabled state.
		 */
		list_for_each_entry(setting, &p->state->settings, node) {
			bool found = false;
			if (setting->type != PIN_MAP_TYPE_MUX_GROUP)
				continue;
			list_for_each_entry(setting2, &state->settings, node) {
				if (setting2->type != PIN_MAP_TYPE_MUX_GROUP)
					continue;
				if (setting2->data.mux.group ==
						setting->data.mux.group) {
					found = true;
					break;
				}
			}
			if (!found)
				pinmux_disable_setting(setting);
		}
	}

	p->state = state;

	/* Apply all the settings for the new state */
	list_for_each_entry(setting, &state->settings, node) {
		switch (setting->type) {
		case PIN_MAP_TYPE_MUX_GROUP:
			ret = pinmux_enable_setting(setting);
			break;
		case PIN_MAP_TYPE_CONFIGS_PIN:
		case PIN_MAP_TYPE_CONFIGS_GROUP:
			ret = pinconf_apply_setting(setting);
			break;
		default:
			ret = -EINVAL;
			break;
		}
		if (ret < 0) {
			/* FIXME: Difficult to return to prev state */
			return ret;
		}
	}

	return 0;
}

/**
 * pinctrl_select() - select/activate/program a pinctrl state to HW
 * @p: the pinctrl handle for the device that requests configuratio
 * @state: the state handle to select/activate/program
 */
int pinctrl_select_state(struct pinctrl *p, struct pinctrl_state *state)
{
	int ret;

	mutex_lock(&pinctrl_mutex);
	ret = pinctrl_select_state_locked(p, state);
	mutex_unlock(&pinctrl_mutex);

	return ret;
}
EXPORT_SYMBOL_GPL(pinctrl_select_state);

static void devm_pinctrl_release(struct device *dev, void *res)
{
	pinctrl_put(*(struct pinctrl **)res);
}

/**
 * struct devm_pinctrl_get() - Resource managed pinctrl_get()
 * @dev: the device to obtain the handle for
 *
 * If there is a need to explicitly destroy the returned struct pinctrl,
 * devm_pinctrl_put() should be used, rather than plain pinctrl_put().
 */
struct pinctrl *devm_pinctrl_get(struct device *dev)
{
	struct pinctrl **ptr, *p;

	ptr = devres_alloc(devm_pinctrl_release, sizeof(*ptr), GFP_KERNEL);
	if (!ptr)
		return ERR_PTR(-ENOMEM);

	p = pinctrl_get(dev);
	if (!IS_ERR(p)) {
		*ptr = p;
		devres_add(dev, ptr);
	} else {
		devres_free(ptr);
	}

	return p;
}
EXPORT_SYMBOL_GPL(devm_pinctrl_get);

static int devm_pinctrl_match(struct device *dev, void *res, void *data)
{
	struct pinctrl **p = res;

	return *p == data;
}

/**
 * devm_pinctrl_put() - Resource managed pinctrl_put()
 * @p: the pinctrl handle to release
 *
 * Deallocate a struct pinctrl obtained via devm_pinctrl_get(). Normally
 * this function will not need to be called and the resource management
 * code will ensure that the resource is freed.
 */
void devm_pinctrl_put(struct pinctrl *p)
{
	WARN_ON(devres_destroy(p->dev, devm_pinctrl_release,
			       devm_pinctrl_match, p));
	pinctrl_put(p);
}
EXPORT_SYMBOL_GPL(devm_pinctrl_put);

int pinctrl_register_map(struct pinctrl_map const *maps, unsigned num_maps,
			 bool dup, bool locked)
{
	int i, ret;
	struct pinctrl_maps *maps_node;

	pr_debug("add %d pinmux maps\n", num_maps);

	/* First sanity check the new mapping */
	for (i = 0; i < num_maps; i++) {
		if (!maps[i].dev_name) {
			pr_err("failed to register map %s (%d): no device given\n",
			       maps[i].name, i);
			return -EINVAL;
		}

		if (!maps[i].name) {
			pr_err("failed to register map %d: no map name given\n",
			       i);
			return -EINVAL;
		}

		if (maps[i].type != PIN_MAP_TYPE_DUMMY_STATE &&
				!maps[i].ctrl_dev_name) {
			pr_err("failed to register map %s (%d): no pin control device given\n",
			       maps[i].name, i);
			return -EINVAL;
		}

		switch (maps[i].type) {
		case PIN_MAP_TYPE_DUMMY_STATE:
			break;
		case PIN_MAP_TYPE_MUX_GROUP:
			ret = pinmux_validate_map(&maps[i], i);
			if (ret < 0)
				return ret;
			break;
		case PIN_MAP_TYPE_CONFIGS_PIN:
		case PIN_MAP_TYPE_CONFIGS_GROUP:
			ret = pinconf_validate_map(&maps[i], i);
			if (ret < 0)
				return ret;
			break;
		default:
			pr_err("failed to register map %s (%d): invalid type given\n",
			       maps[i].name, i);
			return -EINVAL;
		}
	}

	maps_node = kzalloc(sizeof(*maps_node), GFP_KERNEL);
	if (!maps_node) {
		pr_err("failed to alloc struct pinctrl_maps\n");
		return -ENOMEM;
	}

	maps_node->num_maps = num_maps;
	if (dup) {
		maps_node->maps = kmemdup(maps, sizeof(*maps) * num_maps,
					  GFP_KERNEL);
		if (!maps_node->maps) {
			pr_err("failed to duplicate mapping table\n");
			kfree(maps_node);
			return -ENOMEM;
		}
	} else {
		maps_node->maps = maps;
	}

	if (!locked)
		mutex_lock(&pinctrl_mutex);
	list_add_tail(&maps_node->node, &pinctrl_maps);
	if (!locked)
		mutex_unlock(&pinctrl_mutex);

	return 0;
}

/**
 * pinctrl_register_mappings() - register a set of pin controller mappings
 * @maps: the pincontrol mappings table to register. This should probably be
 *	marked with __initdata so it can be discarded after boot. This
 *	function will perform a shallow copy for the mapping entries.
 * @num_maps: the number of maps in the mapping table
 */
int pinctrl_register_mappings(struct pinctrl_map const *maps,
			      unsigned num_maps)
{
	return pinctrl_register_map(maps, num_maps, true, false);
}

void pinctrl_unregister_map(struct pinctrl_map const *map)
{
	struct pinctrl_maps *maps_node;

	list_for_each_entry(maps_node, &pinctrl_maps, node) {
		if (maps_node->maps == map) {
			list_del(&maps_node->node);
			return;
		}
	}
}

#ifdef CONFIG_DEBUG_FS

static int pinctrl_pins_show(struct seq_file *s, void *what)
{
	struct pinctrl_dev *pctldev = s->private;
	const struct pinctrl_ops *ops = pctldev->desc->pctlops;
	unsigned i, pin;

	seq_printf(s, "registered pins: %d\n", pctldev->desc->npins);

	mutex_lock(&pinctrl_mutex);

	/* The pin number can be retrived from the pin controller descriptor */
	for (i = 0; i < pctldev->desc->npins; i++) {
		struct pin_desc *desc;

		pin = pctldev->desc->pins[i].number;
		desc = pin_desc_get(pctldev, pin);
		/* Pin space may be sparse */
		if (desc == NULL)
			continue;

		seq_printf(s, "pin %d (%s) ", pin,
			   desc->name ? desc->name : "unnamed");

		/* Driver-specific info per pin */
		if (ops->pin_dbg_show)
			ops->pin_dbg_show(pctldev, s, pin);

		seq_puts(s, "\n");
	}

	mutex_unlock(&pinctrl_mutex);

	return 0;
}

static int pinctrl_groups_show(struct seq_file *s, void *what)
{
	struct pinctrl_dev *pctldev = s->private;
	const struct pinctrl_ops *ops = pctldev->desc->pctlops;
	unsigned ngroups, selector = 0;

	ngroups = ops->get_groups_count(pctldev);
	mutex_lock(&pinctrl_mutex);

	seq_puts(s, "registered pin groups:\n");
	while (selector < ngroups) {
		const unsigned *pins;
		unsigned num_pins;
		const char *gname = ops->get_group_name(pctldev, selector);
		const char *pname;
		int ret;
		int i;

		ret = ops->get_group_pins(pctldev, selector,
					  &pins, &num_pins);
		if (ret)
			seq_printf(s, "%s [ERROR GETTING PINS]\n",
				   gname);
		else {
			seq_printf(s, "group: %s\n", gname);
			for (i = 0; i < num_pins; i++) {
				pname = pin_get_name(pctldev, pins[i]);
				if (WARN_ON(!pname)) {
					mutex_unlock(&pinctrl_mutex);
					return -EINVAL;
				}
				seq_printf(s, "pin %d (%s)\n", pins[i], pname);
			}
			seq_puts(s, "\n");
		}
		selector++;
	}

	mutex_unlock(&pinctrl_mutex);

	return 0;
}

static int pinctrl_gpioranges_show(struct seq_file *s, void *what)
{
	struct pinctrl_dev *pctldev = s->private;
	struct pinctrl_gpio_range *range = NULL;

	seq_puts(s, "GPIO ranges handled:\n");

	mutex_lock(&pinctrl_mutex);

	/* Loop over the ranges */
	list_for_each_entry(range, &pctldev->gpio_ranges, node) {
		seq_printf(s, "%u: %s GPIOS [%u - %u] PINS [%u - %u]\n",
			   range->id, range->name,
			   range->base, (range->base + range->npins - 1),
			   range->pin_base,
			   (range->pin_base + range->npins - 1));
	}

	mutex_unlock(&pinctrl_mutex);

	return 0;
}

static int pinctrl_devices_show(struct seq_file *s, void *what)
{
	struct pinctrl_dev *pctldev;

	seq_puts(s, "name [pinmux] [pinconf]\n");

	mutex_lock(&pinctrl_mutex);

	list_for_each_entry(pctldev, &pinctrldev_list, node) {
		seq_printf(s, "%s ", pctldev->desc->name);
		if (pctldev->desc->pmxops)
			seq_puts(s, "yes ");
		else
			seq_puts(s, "no ");
		if (pctldev->desc->confops)
			seq_puts(s, "yes");
		else
			seq_puts(s, "no");
		seq_puts(s, "\n");
	}

	mutex_unlock(&pinctrl_mutex);

	return 0;
}

static inline const char *map_type(enum pinctrl_map_type type)
{
	static const char * const names[] = {
		"INVALID",
		"DUMMY_STATE",
		"MUX_GROUP",
		"CONFIGS_PIN",
		"CONFIGS_GROUP",
	};

	if (type >= ARRAY_SIZE(names))
		return "UNKNOWN";

	return names[type];
}

static int pinctrl_maps_show(struct seq_file *s, void *what)
{
	struct pinctrl_maps *maps_node;
	int i;
	struct pinctrl_map const *map;

	seq_puts(s, "Pinctrl maps:\n");

	mutex_lock(&pinctrl_mutex);

	for_each_maps(maps_node, i, map) {
		seq_printf(s, "device %s\nstate %s\ntype %s (%d)\n",
			   map->dev_name, map->name, map_type(map->type),
			   map->type);

		if (map->type != PIN_MAP_TYPE_DUMMY_STATE)
			seq_printf(s, "controlling device %s\n",
				   map->ctrl_dev_name);

		switch (map->type) {
		case PIN_MAP_TYPE_MUX_GROUP:
			pinmux_show_map(s, map);
			break;
		case PIN_MAP_TYPE_CONFIGS_PIN:
		case PIN_MAP_TYPE_CONFIGS_GROUP:
			pinconf_show_map(s, map);
			break;
		default:
			break;
		}

		seq_printf(s, "\n");
	}

	mutex_unlock(&pinctrl_mutex);

	return 0;
}

static int pinctrl_show(struct seq_file *s, void *what)
{
	struct pinctrl *p;
	struct pinctrl_state *state;
	struct pinctrl_setting *setting;

	seq_puts(s, "Requested pin control handlers their pinmux maps:\n");

	mutex_lock(&pinctrl_mutex);

	list_for_each_entry(p, &pinctrl_list, node) {
		seq_printf(s, "device: %s current state: %s\n",
			   dev_name(p->dev),
			   p->state ? p->state->name : "none");

		list_for_each_entry(state, &p->states, node) {
			seq_printf(s, "  state: %s\n", state->name);

			list_for_each_entry(setting, &state->settings, node) {
				struct pinctrl_dev *pctldev = setting->pctldev;

				seq_printf(s, "    type: %s controller %s ",
					   map_type(setting->type),
					   pinctrl_dev_get_name(pctldev));

				switch (setting->type) {
				case PIN_MAP_TYPE_MUX_GROUP:
					pinmux_show_setting(s, setting);
					break;
				case PIN_MAP_TYPE_CONFIGS_PIN:
				case PIN_MAP_TYPE_CONFIGS_GROUP:
					pinconf_show_setting(s, setting);
					break;
				default:
					break;
				}
			}
		}
	}

	mutex_unlock(&pinctrl_mutex);

	return 0;
}

static int pinctrl_pins_open(struct inode *inode, struct file *file)
{
	return single_open(file, pinctrl_pins_show, inode->i_private);
}

static int pinctrl_groups_open(struct inode *inode, struct file *file)
{
	return single_open(file, pinctrl_groups_show, inode->i_private);
}

static int pinctrl_gpioranges_open(struct inode *inode, struct file *file)
{
	return single_open(file, pinctrl_gpioranges_show, inode->i_private);
}

static int pinctrl_devices_open(struct inode *inode, struct file *file)
{
	return single_open(file, pinctrl_devices_show, NULL);
}

static int pinctrl_maps_open(struct inode *inode, struct file *file)
{
	return single_open(file, pinctrl_maps_show, NULL);
}

static int pinctrl_open(struct inode *inode, struct file *file)
{
	return single_open(file, pinctrl_show, NULL);
}

static const struct file_operations pinctrl_pins_ops = {
	.open		= pinctrl_pins_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= single_release,
};

static const struct file_operations pinctrl_groups_ops = {
	.open		= pinctrl_groups_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= single_release,
};

static const struct file_operations pinctrl_gpioranges_ops = {
	.open		= pinctrl_gpioranges_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= single_release,
};

static const struct file_operations pinctrl_devices_ops = {
	.open		= pinctrl_devices_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= single_release,
};

static const struct file_operations pinctrl_maps_ops = {
	.open		= pinctrl_maps_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= single_release,
};

static const struct file_operations pinctrl_ops = {
	.open		= pinctrl_open,
	.read		= seq_read,
	.llseek		= seq_lseek,
	.release	= single_release,
};

static struct dentry *debugfs_root;

static void pinctrl_init_device_debugfs(struct pinctrl_dev *pctldev)
{
	struct dentry *device_root;

	device_root = debugfs_create_dir(dev_name(pctldev->dev),
					 debugfs_root);
	pctldev->device_root = device_root;

	if (IS_ERR(device_root) || !device_root) {
		pr_warn("failed to create debugfs directory for %s\n",
			dev_name(pctldev->dev));
		return;
	}
	debugfs_create_file("pins", S_IFREG | S_IRUGO,
			    device_root, pctldev, &pinctrl_pins_ops);
	debugfs_create_file("pingroups", S_IFREG | S_IRUGO,
			    device_root, pctldev, &pinctrl_groups_ops);
	debugfs_create_file("gpio-ranges", S_IFREG | S_IRUGO,
			    device_root, pctldev, &pinctrl_gpioranges_ops);
	pinmux_init_device_debugfs(device_root, pctldev);
	pinconf_init_device_debugfs(device_root, pctldev);
}

static void pinctrl_remove_device_debugfs(struct pinctrl_dev *pctldev)
{
	debugfs_remove_recursive(pctldev->device_root);
}

static void pinctrl_init_debugfs(void)
{
	debugfs_root = debugfs_create_dir("pinctrl", NULL);
	if (IS_ERR(debugfs_root) || !debugfs_root) {
		pr_warn("failed to create debugfs directory\n");
		debugfs_root = NULL;
		return;
	}

	debugfs_create_file("pinctrl-devices", S_IFREG | S_IRUGO,
			    debugfs_root, NULL, &pinctrl_devices_ops);
	debugfs_create_file("pinctrl-maps", S_IFREG | S_IRUGO,
			    debugfs_root, NULL, &pinctrl_maps_ops);
	debugfs_create_file("pinctrl-handles", S_IFREG | S_IRUGO,
			    debugfs_root, NULL, &pinctrl_ops);
}

#else /* CONFIG_DEBUG_FS */

static void pinctrl_init_device_debugfs(struct pinctrl_dev *pctldev)
{
}

static void pinctrl_init_debugfs(void)
{
}

static void pinctrl_remove_device_debugfs(struct pinctrl_dev *pctldev)
{
}

#endif

static int pinctrl_check_ops(struct pinctrl_dev *pctldev)
{
	const struct pinctrl_ops *ops = pctldev->desc->pctlops;

	if (!ops ||
	    !ops->get_groups_count ||
	    !ops->get_group_name ||
	    !ops->get_group_pins)
		return -EINVAL;

	if (ops->dt_node_to_map && !ops->dt_free_map)
		return -EINVAL;

	return 0;
}

/**
 * pinctrl_register() - register a pin controller device
 * @pctldesc: descriptor for this pin controller
 * @dev: parent device for this pin controller
 * @driver_data: private pin controller data for this pin controller
 */
struct pinctrl_dev *pinctrl_register(struct pinctrl_desc *pctldesc,
				    struct device *dev, void *driver_data)
{
	struct pinctrl_dev *pctldev;
	int ret;

	if (!pctldesc)
		return NULL;
	if (!pctldesc->name)
		return NULL;

	pctldev = kzalloc(sizeof(*pctldev), GFP_KERNEL);
	if (pctldev == NULL) {
		dev_err(dev, "failed to alloc struct pinctrl_dev\n");
		return NULL;
	}

	/* Initialize pin control device struct */
	pctldev->owner = pctldesc->owner;
	pctldev->desc = pctldesc;
	pctldev->driver_data = driver_data;
	INIT_RADIX_TREE(&pctldev->pin_desc_tree, GFP_KERNEL);
	INIT_LIST_HEAD(&pctldev->gpio_ranges);
	pctldev->dev = dev;

	/* check core ops for sanity */
	if (pinctrl_check_ops(pctldev)) {
		dev_err(dev, "pinctrl ops lacks necessary functions\n");
		goto out_err;
	}

	/* If we're implementing pinmuxing, check the ops for sanity */
	if (pctldesc->pmxops) {
		if (pinmux_check_ops(pctldev))
			goto out_err;
	}

	/* If we're implementing pinconfig, check the ops for sanity */
	if (pctldesc->confops) {
		if (pinconf_check_ops(pctldev))
			goto out_err;
	}

	/* Register all the pins */
	dev_dbg(dev, "try to register %d pins ...\n",  pctldesc->npins);
	ret = pinctrl_register_pins(pctldev, pctldesc->pins, pctldesc->npins);
	if (ret) {
		dev_err(dev, "error during pin registration\n");
		pinctrl_free_pindescs(pctldev, pctldesc->pins,
				      pctldesc->npins);
		goto out_err;
	}

	mutex_lock(&pinctrl_mutex);

	list_add_tail(&pctldev->node, &pinctrldev_list);

	pctldev->p = pinctrl_get_locked(pctldev->dev);
	if (!IS_ERR(pctldev->p)) {
		struct pinctrl_state *s =
			pinctrl_lookup_state_locked(pctldev->p,
						    PINCTRL_STATE_DEFAULT);
		if (IS_ERR(s)) {
			dev_dbg(dev, "failed to lookup the default state\n");
		} else {
			if (pinctrl_select_state_locked(pctldev->p, s))
				dev_err(dev,
					"failed to select default state\n");
		}
	}

	mutex_unlock(&pinctrl_mutex);

	pinctrl_init_device_debugfs(pctldev);

	return pctldev;

out_err:
	kfree(pctldev);
	return NULL;
}
EXPORT_SYMBOL_GPL(pinctrl_register);

/**
 * pinctrl_unregister() - unregister pinmux
 * @pctldev: pin controller to unregister
 *
 * Called by pinmux drivers to unregister a pinmux.
 */
void pinctrl_unregister(struct pinctrl_dev *pctldev)
{
	struct pinctrl_gpio_range *range, *n;
	if (pctldev == NULL)
		return;

	pinctrl_remove_device_debugfs(pctldev);

	mutex_lock(&pinctrl_mutex);

	if (!IS_ERR(pctldev->p))
		pinctrl_put_locked(pctldev->p, true);

	/* TODO: check that no pinmuxes are still active? */
	list_del(&pctldev->node);
	/* Destroy descriptor tree */
	pinctrl_free_pindescs(pctldev, pctldev->desc->pins,
			      pctldev->desc->npins);
	/* remove gpio ranges map */
	list_for_each_entry_safe(range, n, &pctldev->gpio_ranges, node)
		list_del(&range->node);

	kfree(pctldev);

	mutex_unlock(&pinctrl_mutex);
}
EXPORT_SYMBOL_GPL(pinctrl_unregister);

static int __init pinctrl_init(void)
{
	pr_info("initialized pinctrl subsystem\n");
	pinctrl_init_debugfs();
	return 0;
}

/* init early since many drivers really need to initialized pinmux early */
core_initcall(pinctrl_init);