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
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Analog Devices AD9467 SPI ADC driver
 *
 * Copyright 2012-2020 Analog Devices Inc.
 */

#include <linux/bitfield.h>
#include <linux/bitmap.h>
#include <linux/bitops.h>
#include <linux/cleanup.h>
#include <linux/clk.h>
#include <linux/debugfs.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/gpio/consumer.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include <linux/spi/spi.h>
#include <linux/units.h>

#include <linux/iio/backend.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>

/*
 * ADI High-Speed ADC common spi interface registers
 * See Application-Note AN-877:
 *   https://www.analog.com/media/en/technical-documentation/application-notes/AN-877.pdf
 */

#define AN877_ADC_REG_CHIP_PORT_CONF		0x00
#define AN877_ADC_REG_CHIP_ID			0x01
#define AN877_ADC_REG_CHIP_GRADE		0x02
#define AN877_ADC_REG_CHAN_INDEX		0x05
#define AN877_ADC_REG_TRANSFER			0xFF
#define AN877_ADC_REG_MODES			0x08
#define AN877_ADC_REG_TEST_IO			0x0D
#define AN877_ADC_REG_ADC_INPUT			0x0F
#define AN877_ADC_REG_OFFSET			0x10
#define AN877_ADC_REG_OUTPUT_MODE		0x14
#define AN877_ADC_REG_OUTPUT_ADJUST		0x15
#define AN877_ADC_REG_OUTPUT_PHASE		0x16
#define AN877_ADC_REG_OUTPUT_DELAY		0x17
#define AN877_ADC_REG_VREF			0x18
#define AN877_ADC_REG_ANALOG_INPUT		0x2C

/* AN877_ADC_REG_TEST_IO */
#define AN877_ADC_TESTMODE_OFF			0x0
#define AN877_ADC_TESTMODE_MIDSCALE_SHORT	0x1
#define AN877_ADC_TESTMODE_POS_FULLSCALE	0x2
#define AN877_ADC_TESTMODE_NEG_FULLSCALE	0x3
#define AN877_ADC_TESTMODE_ALT_CHECKERBOARD	0x4
#define AN877_ADC_TESTMODE_PN23_SEQ		0x5
#define AN877_ADC_TESTMODE_PN9_SEQ		0x6
#define AN877_ADC_TESTMODE_ONE_ZERO_TOGGLE	0x7
#define AN877_ADC_TESTMODE_USER			0x8
#define AN877_ADC_TESTMODE_BIT_TOGGLE		0x9
#define AN877_ADC_TESTMODE_SYNC			0xA
#define AN877_ADC_TESTMODE_ONE_BIT_HIGH		0xB
#define AN877_ADC_TESTMODE_MIXED_BIT_FREQUENCY	0xC
#define AN877_ADC_TESTMODE_RAMP			0xF

/* AN877_ADC_REG_TRANSFER */
#define AN877_ADC_TRANSFER_SYNC			0x1

/* AN877_ADC_REG_OUTPUT_MODE */
#define AN877_ADC_OUTPUT_MODE_OFFSET_BINARY	0x0
#define AN877_ADC_OUTPUT_MODE_TWOS_COMPLEMENT	0x1
#define AN877_ADC_OUTPUT_MODE_GRAY_CODE		0x2
#define AN877_ADC_OUTPUT_MODE_MASK		GENMASK(1, 0)

/* AN877_ADC_REG_OUTPUT_PHASE */
#define AN877_ADC_OUTPUT_EVEN_ODD_MODE_EN	0x20
#define AN877_ADC_INVERT_DCO_CLK		0x80

/* AN877_ADC_REG_OUTPUT_DELAY */
#define AN877_ADC_DCO_DELAY_ENABLE		0x80

/*
 * Analog Devices AD9211 10-Bit, 200/250/300 MSPS ADC
 */

#define CHIPID_AD9211			0x06
#define AD9211_DEF_OUTPUT_MODE		0x01
#define AD9211_REG_VREF_MASK		GENMASK(4, 0)

/*
 * Analog Devices AD9265 16-Bit, 125/105/80 MSPS ADC
 */

#define CHIPID_AD9265			0x64
#define AD9265_DEF_OUTPUT_MODE		0x41
#define AD9265_REG_VREF_MASK		0xC0

/*
 * Analog Devices AD9434 12-Bit, 370/500 MSPS ADC
 */

#define CHIPID_AD9434			0x6A
#define AD9434_DEF_OUTPUT_MODE		0x01
#define AD9434_REG_VREF_MASK		GENMASK(4, 0)

/*
 * Analog Devices AD9467 16-Bit, 200/250 MSPS ADC
 */

#define CHIPID_AD9467			0x50
#define AD9467_DEF_OUTPUT_MODE		0x09
#define AD9467_REG_VREF_MASK		0x0F

/*
 * Analog Devices AD9643 14-Bit, 170/210/250 MSPS ADC
 */

#define CHIPID_AD9643			0x82
#define AD9643_DEF_OUTPUT_MODE		0x01
#define AD9643_REG_VREF_MASK		0x1F

/*
 * Analog Devices AD9652 16-bit 310 MSPS ADC
 */

#define CHIPID_AD9652                   0xC1
#define AD9652_DEF_OUTPUT_MODE		0x01
#define AD9652_REG_VREF_MASK            0xC0

/*
 * Analog Devices AD9649 14-bit 20/40/65/80 MSPS ADC
 */

#define CHIPID_AD9649			0x6F
#define AD9649_DEF_OUTPUT_MODE		0x01
#define AD9649_TEST_POINTS		8

#define AD9647_MAX_TEST_POINTS		32
#define AD9467_CAN_INVERT(st)	\
	(!(st)->info->has_dco || (st)->info->has_dco_invert)

struct ad9467_chip_info {
	const char *name;
	unsigned int id;
	const struct iio_chan_spec *channels;
	unsigned int num_channels;
	const unsigned int (*scale_table)[2];
	int num_scales;
	unsigned long test_mask;
	unsigned int test_mask_len;
	unsigned long max_rate;
	unsigned int default_output_mode;
	unsigned int vref_mask;
	unsigned int num_lanes;
	unsigned int dco_en;
	unsigned int test_points;
	const int *offset_range;
	/* data clock output */
	bool has_dco;
	bool has_dco_invert;
};

struct ad9467_chan_test_mode {
	struct ad9467_state *st;
	unsigned int idx;
	u8 mode;
};

struct ad9467_state {
	const struct ad9467_chip_info *info;
	struct iio_backend *back;
	struct spi_device *spi;
	struct clk *clk;
	/* used for debugfs */
	struct ad9467_chan_test_mode *chan_test;
	unsigned int (*scales)[2];
	/*
	 * Times 2 because we may also invert the signal polarity and run the
	 * calibration again. For some reference on the test points (ad9265) see:
	 * https://www.analog.com/media/en/technical-documentation/data-sheets/ad9265.pdf
	 * at page 38 for the dco output delay. On devices as ad9467, the
	 * calibration is done at the backend level. For the ADI axi-adc:
	 * https://wiki.analog.com/resources/fpga/docs/axi_adc_ip
	 * at the io delay control section.
	 */
	DECLARE_BITMAP(calib_map, AD9647_MAX_TEST_POINTS * 2);
	/* number of bits of the map */
	unsigned int calib_map_size;
	struct gpio_desc *pwrdown_gpio;
	/* ensure consistent state obtained on multiple related accesses */
	struct mutex lock;
	u8 buf[3] __aligned(IIO_DMA_MINALIGN);
};

static int ad9467_spi_read(struct ad9467_state *st, unsigned int reg)
{
	unsigned char tbuf[2], rbuf[1];
	int ret;

	tbuf[0] = 0x80 | (reg >> 8);
	tbuf[1] = reg & 0xFF;

	ret = spi_write_then_read(st->spi,
				  tbuf, ARRAY_SIZE(tbuf),
				  rbuf, ARRAY_SIZE(rbuf));

	if (ret < 0)
		return ret;

	return rbuf[0];
}

static int ad9467_spi_write(struct ad9467_state *st, unsigned int reg,
			    unsigned int val)
{
	st->buf[0] = reg >> 8;
	st->buf[1] = reg & 0xFF;
	st->buf[2] = val;

	return spi_write(st->spi, st->buf, ARRAY_SIZE(st->buf));
}

static int ad9467_reg_access(struct iio_dev *indio_dev, unsigned int reg,
			     unsigned int writeval, unsigned int *readval)
{
	struct ad9467_state *st = iio_priv(indio_dev);
	int ret;

	if (!readval) {
		guard(mutex)(&st->lock);
		ret = ad9467_spi_write(st, reg, writeval);
		if (ret)
			return ret;
		return ad9467_spi_write(st, AN877_ADC_REG_TRANSFER,
					AN877_ADC_TRANSFER_SYNC);
	}

	ret = ad9467_spi_read(st, reg);
	if (ret < 0)
		return ret;
	*readval = ret;

	return 0;
}

static const int ad9434_offset_range[] = {
	-128, 1, 127,
};

static const unsigned int ad9211_scale_table[][2] = {
	{980, 0x10}, {1000, 0x11}, {1020, 0x12}, {1040, 0x13},
	{1060, 0x14}, {1080, 0x15}, {1100, 0x16}, {1120, 0x17},
	{1140, 0x18}, {1160, 0x19}, {1180, 0x1A}, {1190, 0x1B},
	{1200, 0x1C}, {1210, 0x1D}, {1220, 0x1E}, {1230, 0x1F},
	{1250, 0x0}, {1270, 0x1}, {1290, 0x2}, {1310, 0x3},
	{1330, 0x4}, {1350, 0x5}, {1370, 0x6}, {1390, 0x7},
	{1410, 0x8}, {1430, 0x9}, {1450, 0xA}, {1460, 0xB},
	{1470, 0xC}, {1480, 0xD}, {1490, 0xE}, {1500, 0xF},
};

static const unsigned int ad9265_scale_table[][2] = {
	{1250, 0x00}, {1500, 0x40}, {1750, 0x80}, {2000, 0xC0},
};

static const unsigned int ad9434_scale_table[][2] = {
	{1600, 0x1C}, {1580, 0x1D}, {1550, 0x1E}, {1520, 0x1F}, {1500, 0x00},
	{1470, 0x01}, {1440, 0x02}, {1420, 0x03}, {1390, 0x04}, {1360, 0x05},
	{1340, 0x06}, {1310, 0x07}, {1280, 0x08}, {1260, 0x09}, {1230, 0x0A},
	{1200, 0x0B}, {1180, 0x0C},
};

static const unsigned int ad9467_scale_table[][2] = {
	{2000, 0}, {2100, 6}, {2200, 7},
	{2300, 8}, {2400, 9}, {2500, 10},
};

static const unsigned int ad9643_scale_table[][2] = {
	{2087, 0x0F}, {2065, 0x0E}, {2042, 0x0D}, {2020, 0x0C}, {1997, 0x0B},
	{1975, 0x0A}, {1952, 0x09}, {1930, 0x08}, {1907, 0x07}, {1885, 0x06},
	{1862, 0x05}, {1840, 0x04}, {1817, 0x03}, {1795, 0x02}, {1772, 0x01},
	{1750, 0x00}, {1727, 0x1F}, {1704, 0x1E}, {1681, 0x1D}, {1658, 0x1C},
	{1635, 0x1B}, {1612, 0x1A}, {1589, 0x19}, {1567, 0x18}, {1544, 0x17},
	{1521, 0x16}, {1498, 0x15}, {1475, 0x14}, {1452, 0x13}, {1429, 0x12},
	{1406, 0x11}, {1383, 0x10},
};

static const unsigned int ad9649_scale_table[][2] = {
	 {2000, 0},
};

static const unsigned int ad9652_scale_table[][2] = {
	 {1250, 0}, {1125, 1}, {1200, 2}, {1250, 3}, {1000, 5},
};

static void __ad9467_get_scale(struct ad9467_state *st, int index,
			       unsigned int *val, unsigned int *val2)
{
	const struct ad9467_chip_info *info = st->info;
	const struct iio_chan_spec *chan = &info->channels[0];
	unsigned int tmp;

	tmp = (info->scale_table[index][0] * 1000000ULL) >>
			chan->scan_type.realbits;
	*val = tmp / 1000000;
	*val2 = tmp % 1000000;
}

#define AD9467_CHAN(_chan, avai_mask, _si, _bits, _sign)		\
{									\
	.type = IIO_VOLTAGE,						\
	.indexed = 1,							\
	.channel = _chan,						\
	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) |		\
		BIT(IIO_CHAN_INFO_SAMP_FREQ),				\
	.info_mask_shared_by_type_available = avai_mask,		\
	.scan_index = _si,						\
	.scan_type = {							\
		.sign = _sign,						\
		.realbits = _bits,					\
		.storagebits = 16,					\
	},								\
}

static const struct iio_chan_spec ad9211_channels[] = {
	AD9467_CHAN(0, BIT(IIO_CHAN_INFO_SCALE), 0, 10, 's'),
};

static const struct iio_chan_spec ad9434_channels[] = {
	{
		.type = IIO_VOLTAGE,
		.indexed = 1,
		.channel = 0,
		.info_mask_shared_by_type =
			BIT(IIO_CHAN_INFO_SCALE) |
			BIT(IIO_CHAN_INFO_SAMP_FREQ) |
			BIT(IIO_CHAN_INFO_CALIBBIAS),
		.info_mask_shared_by_type_available =
			BIT(IIO_CHAN_INFO_SCALE) |
			BIT(IIO_CHAN_INFO_CALIBBIAS),
		.scan_index = 0,
		.scan_type = {
			.sign = 's',
			.realbits = 12,
			.storagebits = 16,
		},
	},
};

static const struct iio_chan_spec ad9467_channels[] = {
	AD9467_CHAN(0, BIT(IIO_CHAN_INFO_SCALE), 0, 16, 's'),
};

static const struct iio_chan_spec ad9643_channels[] = {
	AD9467_CHAN(0, BIT(IIO_CHAN_INFO_SCALE), 0, 14, 's'),
	AD9467_CHAN(1, BIT(IIO_CHAN_INFO_SCALE), 1, 14, 's'),
};

static const struct iio_chan_spec ad9649_channels[] = {
	AD9467_CHAN(0, 0, 0, 14, 's'),
};

static const struct iio_chan_spec ad9652_channels[] = {
	AD9467_CHAN(0, BIT(IIO_CHAN_INFO_SCALE), 0, 16, 's'),
	AD9467_CHAN(1, BIT(IIO_CHAN_INFO_SCALE), 1, 16, 's'),
};

static const char * const ad9467_test_modes[] = {
	[AN877_ADC_TESTMODE_OFF] = "off",
	[AN877_ADC_TESTMODE_MIDSCALE_SHORT] = "midscale_short",
	[AN877_ADC_TESTMODE_POS_FULLSCALE] = "pos_fullscale",
	[AN877_ADC_TESTMODE_NEG_FULLSCALE] = "neg_fullscale",
	[AN877_ADC_TESTMODE_ALT_CHECKERBOARD] = "checkerboard",
	[AN877_ADC_TESTMODE_PN23_SEQ] = "prbs23",
	[AN877_ADC_TESTMODE_PN9_SEQ] = "prbs9",
	[AN877_ADC_TESTMODE_ONE_ZERO_TOGGLE] = "one_zero_toggle",
	[AN877_ADC_TESTMODE_USER] = "user",
	[AN877_ADC_TESTMODE_BIT_TOGGLE] = "bit_toggle",
	[AN877_ADC_TESTMODE_SYNC] = "sync",
	[AN877_ADC_TESTMODE_ONE_BIT_HIGH] = "one_bit_high",
	[AN877_ADC_TESTMODE_MIXED_BIT_FREQUENCY] = "mixed_bit_frequency",
	[AN877_ADC_TESTMODE_RAMP] = "ramp",
};

static const struct ad9467_chip_info ad9467_chip_tbl = {
	.name = "ad9467",
	.id = CHIPID_AD9467,
	.max_rate = 250000000UL,
	.scale_table = ad9467_scale_table,
	.num_scales = ARRAY_SIZE(ad9467_scale_table),
	.channels = ad9467_channels,
	.num_channels = ARRAY_SIZE(ad9467_channels),
	.test_points = AD9647_MAX_TEST_POINTS,
	.test_mask = GENMASK(AN877_ADC_TESTMODE_ONE_ZERO_TOGGLE,
			     AN877_ADC_TESTMODE_OFF),
	.test_mask_len = AN877_ADC_TESTMODE_ONE_ZERO_TOGGLE + 1,
	.default_output_mode = AD9467_DEF_OUTPUT_MODE,
	.vref_mask = AD9467_REG_VREF_MASK,
	.num_lanes = 8,
};

static const struct ad9467_chip_info ad9434_chip_tbl = {
	.name = "ad9434",
	.id = CHIPID_AD9434,
	.max_rate = 500000000UL,
	.scale_table = ad9434_scale_table,
	.num_scales = ARRAY_SIZE(ad9434_scale_table),
	.channels = ad9434_channels,
	.num_channels = ARRAY_SIZE(ad9434_channels),
	.test_points = AD9647_MAX_TEST_POINTS,
	.test_mask = GENMASK(AN877_ADC_TESTMODE_USER, AN877_ADC_TESTMODE_OFF),
	.test_mask_len = AN877_ADC_TESTMODE_USER + 1,
	.default_output_mode = AD9434_DEF_OUTPUT_MODE,
	.vref_mask = AD9434_REG_VREF_MASK,
	.num_lanes = 6,
	.offset_range = ad9434_offset_range,
};

static const struct ad9467_chip_info ad9211_chip_tbl = {
	.name = "ad9211",
	.id = CHIPID_AD9211,
	.max_rate = 300 * HZ_PER_MHZ,
	.scale_table = ad9211_scale_table,
	.num_scales = ARRAY_SIZE(ad9211_scale_table),
	.channels = ad9211_channels,
	.num_channels = ARRAY_SIZE(ad9211_channels),
	.test_points = AD9647_MAX_TEST_POINTS,
	.test_mask = GENMASK(AN877_ADC_TESTMODE_ONE_ZERO_TOGGLE,
			     AN877_ADC_TESTMODE_OFF),
	.test_mask_len = AN877_ADC_TESTMODE_ONE_ZERO_TOGGLE + 1,
	.default_output_mode = AD9211_DEF_OUTPUT_MODE,
	.vref_mask = AD9211_REG_VREF_MASK,
	.has_dco = true,
};

static const struct ad9467_chip_info ad9265_chip_tbl = {
	.name = "ad9265",
	.id = CHIPID_AD9265,
	.max_rate = 125000000UL,
	.scale_table = ad9265_scale_table,
	.num_scales = ARRAY_SIZE(ad9265_scale_table),
	.channels = ad9467_channels,
	.num_channels = ARRAY_SIZE(ad9467_channels),
	.test_points = AD9647_MAX_TEST_POINTS,
	.test_mask = GENMASK(AN877_ADC_TESTMODE_ONE_ZERO_TOGGLE,
			     AN877_ADC_TESTMODE_OFF),
	.test_mask_len = AN877_ADC_TESTMODE_ONE_ZERO_TOGGLE + 1,
	.default_output_mode = AD9265_DEF_OUTPUT_MODE,
	.vref_mask = AD9265_REG_VREF_MASK,
	.has_dco = true,
	.has_dco_invert = true,
};

static const struct ad9467_chip_info ad9643_chip_tbl = {
	.name = "ad9643",
	.id = CHIPID_AD9643,
	.max_rate = 250000000UL,
	.scale_table = ad9643_scale_table,
	.num_scales = ARRAY_SIZE(ad9643_scale_table),
	.channels = ad9643_channels,
	.num_channels = ARRAY_SIZE(ad9643_channels),
	.test_points = AD9647_MAX_TEST_POINTS,
	.test_mask = BIT(AN877_ADC_TESTMODE_RAMP) |
		GENMASK(AN877_ADC_TESTMODE_MIXED_BIT_FREQUENCY, AN877_ADC_TESTMODE_OFF),
	.test_mask_len = AN877_ADC_TESTMODE_RAMP + 1,
	.default_output_mode = AD9643_DEF_OUTPUT_MODE,
	.vref_mask = AD9643_REG_VREF_MASK,
	.has_dco = true,
	.has_dco_invert = true,
	.dco_en = AN877_ADC_DCO_DELAY_ENABLE,
};

static const struct ad9467_chip_info ad9649_chip_tbl = {
	.name = "ad9649",
	.id = CHIPID_AD9649,
	.max_rate = 80000000UL,
	.scale_table = ad9649_scale_table,
	.num_scales = ARRAY_SIZE(ad9649_scale_table),
	.channels = ad9649_channels,
	.num_channels = ARRAY_SIZE(ad9649_channels),
	.test_points = AD9649_TEST_POINTS,
	.test_mask = GENMASK(AN877_ADC_TESTMODE_MIXED_BIT_FREQUENCY,
			     AN877_ADC_TESTMODE_OFF),
	.test_mask_len = AN877_ADC_TESTMODE_MIXED_BIT_FREQUENCY + 1,
	.default_output_mode = AD9649_DEF_OUTPUT_MODE,
	.has_dco = true,
	.has_dco_invert = true,
	.dco_en = AN877_ADC_DCO_DELAY_ENABLE,
};

static const struct ad9467_chip_info ad9652_chip_tbl = {
	.name = "ad9652",
	.id = CHIPID_AD9652,
	.max_rate = 310000000UL,
	.scale_table = ad9652_scale_table,
	.num_scales = ARRAY_SIZE(ad9652_scale_table),
	.channels = ad9652_channels,
	.num_channels = ARRAY_SIZE(ad9652_channels),
	.test_points = AD9647_MAX_TEST_POINTS,
	.test_mask = GENMASK(AN877_ADC_TESTMODE_ONE_ZERO_TOGGLE,
			     AN877_ADC_TESTMODE_OFF),
	.test_mask_len = AN877_ADC_TESTMODE_ONE_ZERO_TOGGLE + 1,
	.default_output_mode = AD9652_DEF_OUTPUT_MODE,
	.vref_mask = AD9652_REG_VREF_MASK,
	.has_dco = true,
};

static int ad9467_get_scale(struct ad9467_state *st, int *val, int *val2)
{
	const struct ad9467_chip_info *info = st->info;
	unsigned int vref_val;
	unsigned int i = 0;
	int ret;

	/* nothing to read if we only have one possible scale */
	if (info->num_scales == 1)
		goto out_get_scale;

	ret = ad9467_spi_read(st, AN877_ADC_REG_VREF);
	if (ret < 0)
		return ret;

	vref_val = ret & info->vref_mask;

	for (i = 0; i < info->num_scales; i++) {
		if (vref_val == info->scale_table[i][1])
			break;
	}

	if (i == info->num_scales)
		return -ERANGE;

out_get_scale:
	__ad9467_get_scale(st, i, val, val2);

	return IIO_VAL_INT_PLUS_MICRO;
}

static int ad9467_set_scale(struct ad9467_state *st, int val, int val2)
{
	const struct ad9467_chip_info *info = st->info;
	unsigned int scale_val[2];
	unsigned int i;
	int ret;

	if (val != 0)
		return -EINVAL;
	if (info->num_scales == 1)
		return -EOPNOTSUPP;

	for (i = 0; i < info->num_scales; i++) {
		__ad9467_get_scale(st, i, &scale_val[0], &scale_val[1]);
		if (scale_val[0] != val || scale_val[1] != val2)
			continue;

		guard(mutex)(&st->lock);
		ret = ad9467_spi_write(st, AN877_ADC_REG_VREF,
				       info->scale_table[i][1]);
		if (ret < 0)
			return ret;

		return ad9467_spi_write(st, AN877_ADC_REG_TRANSFER,
					AN877_ADC_TRANSFER_SYNC);
	}

	return -EINVAL;
}

static int ad9467_get_offset(struct ad9467_state *st, int *val)
{
	int ret;

	ret = ad9467_spi_read(st, AN877_ADC_REG_OFFSET);
	if (ret < 0)
		return ret;
	*val = ret;

	return IIO_VAL_INT;
}

static int ad9467_set_offset(struct ad9467_state *st, int val)
{
	int ret;

	if (val < st->info->offset_range[0] || val > st->info->offset_range[2])
		return -EINVAL;

	ret = ad9467_spi_write(st, AN877_ADC_REG_OFFSET, val);
	if (ret < 0)
		return ret;

	return ad9467_spi_write(st, AN877_ADC_REG_TRANSFER,
				AN877_ADC_TRANSFER_SYNC);
}

static int ad9467_outputmode_set(struct ad9467_state *st, unsigned int mode)
{
	int ret;

	ret = ad9467_spi_write(st, AN877_ADC_REG_OUTPUT_MODE, mode);
	if (ret < 0)
		return ret;

	return ad9467_spi_write(st, AN877_ADC_REG_TRANSFER,
				AN877_ADC_TRANSFER_SYNC);
}

static int ad9467_testmode_set(struct ad9467_state *st, unsigned int chan,
			       unsigned int test_mode)
{
	int ret;

	if (st->info->num_channels > 1) {
		/* so that the test mode is only applied to one channel */
		ret = ad9467_spi_write(st, AN877_ADC_REG_CHAN_INDEX, BIT(chan));
		if (ret)
			return ret;
	}

	ret = ad9467_spi_write(st, AN877_ADC_REG_TEST_IO, test_mode);
	if (ret)
		return ret;

	if (st->info->num_channels > 1) {
		/* go to default state where all channels get write commands */
		ret = ad9467_spi_write(st, AN877_ADC_REG_CHAN_INDEX,
				       GENMASK(st->info->num_channels - 1, 0));
		if (ret)
			return ret;
	}

	return ad9467_spi_write(st, AN877_ADC_REG_TRANSFER,
				AN877_ADC_TRANSFER_SYNC);
}

static int ad9467_backend_testmode_on(struct ad9467_state *st,
				      unsigned int chan,
				      enum iio_backend_test_pattern pattern)
{
	struct iio_backend_data_fmt data = {
		.enable = false,
	};
	int ret;

	ret = iio_backend_data_format_set(st->back, chan, &data);
	if (ret)
		return ret;

	ret = iio_backend_test_pattern_set(st->back, chan, pattern);
	if (ret)
		return ret;

	return iio_backend_chan_enable(st->back, chan);
}

static int ad9467_backend_testmode_off(struct ad9467_state *st,
				       unsigned int chan)
{
	struct iio_backend_data_fmt data = {
		.enable = true,
		.sign_extend = true,
	};
	int ret;

	ret = iio_backend_chan_disable(st->back, chan);
	if (ret)
		return ret;

	ret = iio_backend_test_pattern_set(st->back, chan,
					   IIO_BACKEND_NO_TEST_PATTERN);
	if (ret)
		return ret;

	return iio_backend_data_format_set(st->back, chan, &data);
}

static int ad9647_calibrate_prepare(struct ad9467_state *st)
{
	unsigned int cmode;
	unsigned int c;
	int ret;

	cmode = st->info->default_output_mode;
	FIELD_MODIFY(AN877_ADC_OUTPUT_MODE_MASK, &cmode,
		     AN877_ADC_OUTPUT_MODE_OFFSET_BINARY);
	ret = ad9467_outputmode_set(st, cmode);
	if (ret)
		return ret;

	for (c = 0; c < st->info->num_channels; c++) {
		ret = ad9467_testmode_set(st, c, AN877_ADC_TESTMODE_PN9_SEQ);
		if (ret)
			return ret;

		ret = ad9467_backend_testmode_on(st, c,
						 IIO_BACKEND_ADI_PRBS_9A);
		if (ret)
			return ret;
	}

	return 0;
}

static int ad9647_calibrate_polarity_set(struct ad9467_state *st,
					 bool invert)
{
	enum iio_backend_sample_trigger trigger;

	if (st->info->has_dco) {
		unsigned int phase = AN877_ADC_OUTPUT_EVEN_ODD_MODE_EN;

		if (invert)
			phase |= AN877_ADC_INVERT_DCO_CLK;

		return ad9467_spi_write(st, AN877_ADC_REG_OUTPUT_PHASE,
					phase);
	}

	if (invert)
		trigger = IIO_BACKEND_SAMPLE_TRIGGER_EDGE_FALLING;
	else
		trigger = IIO_BACKEND_SAMPLE_TRIGGER_EDGE_RISING;

	return iio_backend_data_sample_trigger(st->back, trigger);
}

/*
 * The idea is pretty simple. Find the max number of successful points in a row
 * and get the one in the middle.
 */
static unsigned int ad9467_find_optimal_point(const unsigned long *calib_map,
					      unsigned int start,
					      unsigned int nbits,
					      unsigned int *val)
{
	unsigned int bit = start, end, start_cnt, cnt = 0;

	for_each_clear_bitrange_from(bit, end, calib_map, nbits + start) {
		if (end - bit > cnt) {
			cnt = end - bit;
			start_cnt = bit;
		}
	}

	if (cnt)
		*val = start_cnt + cnt / 2;

	return cnt;
}

static int ad9467_calibrate_apply(struct ad9467_state *st, unsigned int val)
{
	unsigned int lane;
	int ret;

	if (st->info->has_dco) {
		ret = ad9467_spi_write(st, AN877_ADC_REG_OUTPUT_DELAY,
				       val | st->info->dco_en);
		if (ret)
			return ret;

		return ad9467_spi_write(st, AN877_ADC_REG_TRANSFER,
					AN877_ADC_TRANSFER_SYNC);
	}

	for (lane = 0; lane < st->info->num_lanes; lane++) {
		ret = iio_backend_iodelay_set(st->back, lane, val);
		if (ret)
			return ret;
	}

	return 0;
}

static int ad9647_calibrate_stop(struct ad9467_state *st)
{
	unsigned int c, mode;
	int ret;

	for (c = 0; c < st->info->num_channels; c++) {
		ret = ad9467_backend_testmode_off(st, c);
		if (ret)
			return ret;

		ret = ad9467_testmode_set(st, c, AN877_ADC_TESTMODE_OFF);
		if (ret)
			return ret;
	}

	mode = st->info->default_output_mode;
	return ad9467_outputmode_set(st, mode);
}

static int ad9467_calibrate(struct ad9467_state *st)
{
	unsigned int point, val, inv_val, cnt, inv_cnt = 0, c;
	/*
	 * Half of the bitmap is for the inverted signal. The number of test
	 * points is the same though...
	 */
	unsigned int test_points = st->info->test_points;
	unsigned long sample_rate = clk_get_rate(st->clk);
	struct device *dev = &st->spi->dev;
	bool invert = false, stat;
	int ret;

	/* all points invalid */
	bitmap_fill(st->calib_map, st->calib_map_size);

	ret = ad9647_calibrate_prepare(st);
	if (ret)
		return ret;
retune:
	ret = ad9647_calibrate_polarity_set(st, invert);
	if (ret)
		return ret;

	for (point = 0; point < st->info->test_points; point++) {
		ret = ad9467_calibrate_apply(st, point);
		if (ret)
			return ret;

		for (c = 0; c < st->info->num_channels; c++) {
			ret = iio_backend_chan_status(st->back, c, &stat);
			if (ret)
				return ret;

			/*
			 * A point is considered valid if all channels report no
			 * error. If one reports an error, then we consider the
			 * point as invalid and we can break the loop right away.
			 */
			if (stat) {
				dev_dbg(dev, "Invalid point(%u, inv:%u) for CH:%u\n",
					point, invert, c);
				break;
			}

			if (c == st->info->num_channels - 1)
				__clear_bit(point + invert * test_points,
					    st->calib_map);
		}
	}

	if (!invert) {
		cnt = ad9467_find_optimal_point(st->calib_map, 0, test_points,
						&val);
		/*
		 * We're happy if we find, at least, three good test points in
		 * a row.
		 */
		if (cnt < 3) {
			if (AD9467_CAN_INVERT(st)) {
				invert = true;
				goto retune;
			}

			if (!cnt)
				return -EIO;
		}
	} else {
		inv_cnt = ad9467_find_optimal_point(st->calib_map, test_points,
						    test_points, &inv_val);
		if (!inv_cnt && !cnt)
			return -EIO;
	}

	if (inv_cnt < cnt) {
		ret = ad9647_calibrate_polarity_set(st, false);
		if (ret)
			return ret;
	} else {
		/*
		 * polarity inverted is the last test to run. Hence, there's no
		 * need to re-do any configuration. We just need to "normalize"
		 * the selected value.
		 */
		val = inv_val - test_points;
	}

	if (st->info->has_dco)
		dev_dbg(dev, "%sDCO 0x%X CLK %lu Hz\n", inv_cnt >= cnt ? "INVERT " : "",
			val, sample_rate);
	else
		dev_dbg(dev, "%sIDELAY 0x%x\n", inv_cnt >= cnt ? "INVERT " : "",
			val);

	ret = ad9467_calibrate_apply(st, val);
	if (ret)
		return ret;

	/* finally apply the optimal value */
	return ad9647_calibrate_stop(st);
}

static int ad9467_read_raw(struct iio_dev *indio_dev,
			   struct iio_chan_spec const *chan,
			   int *val, int *val2, long m)
{
	struct ad9467_state *st = iio_priv(indio_dev);

	switch (m) {
	case IIO_CHAN_INFO_CALIBBIAS:
		return ad9467_get_offset(st, val);
	case IIO_CHAN_INFO_SCALE:
		return ad9467_get_scale(st, val, val2);
	case IIO_CHAN_INFO_SAMP_FREQ:
		*val = clk_get_rate(st->clk);

		return IIO_VAL_INT;
	default:
		return -EINVAL;
	}
}

static int __ad9467_update_clock(struct ad9467_state *st, long r_clk)
{
	int ret;

	ret = clk_set_rate(st->clk, r_clk);
	if (ret)
		return ret;

	guard(mutex)(&st->lock);

	if (iio_backend_has_caps(st->back, IIO_BACKEND_CAP_CALIBRATION))
		return ad9467_calibrate(st);

	return 0;
}

static int ad9467_write_raw(struct iio_dev *indio_dev,
			    struct iio_chan_spec const *chan,
			    int val, int val2, long mask)
{
	struct ad9467_state *st = iio_priv(indio_dev);
	const struct ad9467_chip_info *info = st->info;
	unsigned long sample_rate;
	long r_clk;
	int ret;

	switch (mask) {
	case IIO_CHAN_INFO_CALIBBIAS:
		return ad9467_set_offset(st, val);
	case IIO_CHAN_INFO_SCALE:
		return ad9467_set_scale(st, val, val2);
	case IIO_CHAN_INFO_SAMP_FREQ:
		r_clk = clk_round_rate(st->clk, val);
		if (r_clk < 0 || r_clk > info->max_rate) {
			dev_warn(&st->spi->dev,
				 "Error setting ADC sample rate %ld", r_clk);
			return -EINVAL;
		}

		sample_rate = clk_get_rate(st->clk);
		/*
		 * clk_set_rate() would also do this but since we would still
		 * need it for avoiding an unnecessary calibration, do it now.
		 */
		if (sample_rate == r_clk)
			return 0;

		if (!iio_device_claim_direct(indio_dev))
			return -EBUSY;

		ret = __ad9467_update_clock(st, r_clk);
		iio_device_release_direct(indio_dev);
		return ret;
	default:
		return -EINVAL;
	}
}

static int ad9467_read_avail(struct iio_dev *indio_dev,
			     struct iio_chan_spec const *chan,
			     const int **vals, int *type, int *length,
			     long mask)
{
	struct ad9467_state *st = iio_priv(indio_dev);
	const struct ad9467_chip_info *info = st->info;

	switch (mask) {
	case IIO_CHAN_INFO_CALIBBIAS:
		*type = IIO_VAL_INT;
		*vals = info->offset_range;
		return IIO_AVAIL_RANGE;
	case IIO_CHAN_INFO_SCALE:
		*vals = (const int *)st->scales;
		*type = IIO_VAL_INT_PLUS_MICRO;
		/* Values are stored in a 2D matrix */
		*length = info->num_scales * 2;
		return IIO_AVAIL_LIST;
	default:
		return -EINVAL;
	}
}

static int ad9467_update_scan_mode(struct iio_dev *indio_dev,
				   const unsigned long *scan_mask)
{
	struct ad9467_state *st = iio_priv(indio_dev);
	unsigned int c;
	int ret;

	for (c = 0; c < st->info->num_channels; c++) {
		if (test_bit(c, scan_mask))
			ret = iio_backend_chan_enable(st->back, c);
		else
			ret = iio_backend_chan_disable(st->back, c);
		if (ret)
			return ret;
	}

	return 0;
}

static const struct iio_info ad9467_info = {
	.read_raw = ad9467_read_raw,
	.write_raw = ad9467_write_raw,
	.update_scan_mode = ad9467_update_scan_mode,
	.debugfs_reg_access = ad9467_reg_access,
	.read_avail = ad9467_read_avail,
};

/* Same as above, but without .read_avail */
static const struct iio_info ad9467_info_no_read_avail = {
	.read_raw = ad9467_read_raw,
	.write_raw = ad9467_write_raw,
	.update_scan_mode = ad9467_update_scan_mode,
	.debugfs_reg_access = ad9467_reg_access,
};

static int ad9467_scale_fill(struct ad9467_state *st)
{
	const struct ad9467_chip_info *info = st->info;
	unsigned int i, val1, val2;

	st->scales = devm_kmalloc_array(&st->spi->dev, info->num_scales,
					sizeof(*st->scales), GFP_KERNEL);
	if (!st->scales)
		return -ENOMEM;

	for (i = 0; i < info->num_scales; i++) {
		__ad9467_get_scale(st, i, &val1, &val2);
		st->scales[i][0] = val1;
		st->scales[i][1] = val2;
	}

	return 0;
}

static int ad9467_reset(struct device *dev)
{
	struct gpio_desc *gpio;

	gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
	if (IS_ERR_OR_NULL(gpio))
		return PTR_ERR_OR_ZERO(gpio);

	fsleep(1);
	gpiod_set_value_cansleep(gpio, 0);
	fsleep(10 * USEC_PER_MSEC);

	return 0;
}

static int ad9467_iio_backend_get(struct ad9467_state *st)
{
	struct device *dev = &st->spi->dev;
	struct device_node *__back;

	st->back = devm_iio_backend_get(dev, NULL);
	if (!IS_ERR(st->back))
		return 0;
	/* If not found, don't error out as we might have legacy DT property */
	if (PTR_ERR(st->back) != -ENOENT)
		return PTR_ERR(st->back);

	/*
	 * if we don't get the backend using the normal API's, use the legacy
	 * 'adi,adc-dev' property. So we get all nodes with that property, and
	 * look for the one pointing at us. Then we directly lookup that fwnode
	 * on the backend list of registered devices. This is done so we don't
	 * make io-backends mandatory which would break DT ABI.
	 */
	for_each_node_with_property(__back, "adi,adc-dev") {
		struct device_node *__me;

		__me = of_parse_phandle(__back, "adi,adc-dev", 0);
		if (!__me)
			continue;

		if (!device_match_of_node(dev, __me)) {
			of_node_put(__me);
			continue;
		}

		of_node_put(__me);
		st->back = __devm_iio_backend_get_from_fwnode_lookup(dev,
								     of_fwnode_handle(__back));
		of_node_put(__back);
		return PTR_ERR_OR_ZERO(st->back);
	}

	return -ENODEV;
}

static int ad9467_test_mode_available_show(struct seq_file *s, void *ignored)
{
	struct ad9467_state *st = s->private;
	unsigned int bit;

	for_each_set_bit(bit, &st->info->test_mask, st->info->test_mask_len)
		seq_printf(s, "%s\n", ad9467_test_modes[bit]);

	return 0;
}
DEFINE_SHOW_ATTRIBUTE(ad9467_test_mode_available);

static ssize_t ad9467_chan_test_mode_read(struct file *file,
					  char __user *userbuf, size_t count,
					  loff_t *ppos)
{
	struct ad9467_chan_test_mode *chan = file->private_data;
	struct ad9467_state *st = chan->st;
	char buf[128] = {0};
	size_t len;
	int ret;

	if (chan->mode == AN877_ADC_TESTMODE_PN9_SEQ ||
	    chan->mode == AN877_ADC_TESTMODE_PN23_SEQ) {
		len = scnprintf(buf, sizeof(buf), "Running \"%s\" Test:\n\t",
				ad9467_test_modes[chan->mode]);

		if (iio_backend_has_caps(st->back, IIO_BACKEND_CAP_CALIBRATION)) {
			ret = iio_backend_debugfs_print_chan_status(st->back,
								    chan->idx,
								    buf + len,
								    sizeof(buf) - len);
			if (ret < 0)
				return ret;
			len += ret;
		}
	} else if (chan->mode == AN877_ADC_TESTMODE_OFF) {
		len = scnprintf(buf, sizeof(buf), "No test Running...\n");
	} else {
		len = scnprintf(buf, sizeof(buf), "Running \"%s\" Test on CH:%u\n",
				ad9467_test_modes[chan->mode], chan->idx);
	}

	return simple_read_from_buffer(userbuf, count, ppos, buf, len);
}

static ssize_t ad9467_chan_test_mode_write(struct file *file,
					   const char __user *userbuf,
					   size_t count, loff_t *ppos)
{
	struct ad9467_chan_test_mode *chan = file->private_data;
	struct ad9467_state *st = chan->st;
	char test_mode[32] = {0};
	unsigned int mode;
	int ret;

	ret = simple_write_to_buffer(test_mode, sizeof(test_mode) - 1, ppos,
				     userbuf, count);
	if (ret < 0)
		return ret;

	for_each_set_bit(mode, &st->info->test_mask, st->info->test_mask_len) {
		if (sysfs_streq(test_mode, ad9467_test_modes[mode]))
			break;
	}

	if (mode == st->info->test_mask_len)
		return -EINVAL;

	guard(mutex)(&st->lock);

	if (mode == AN877_ADC_TESTMODE_OFF) {
		unsigned int out_mode;

		if (iio_backend_has_caps(st->back, IIO_BACKEND_CAP_CALIBRATION)) {
			if (chan->mode == AN877_ADC_TESTMODE_PN9_SEQ ||
			    chan->mode == AN877_ADC_TESTMODE_PN23_SEQ) {
				ret = ad9467_backend_testmode_off(st, chan->idx);
				if (ret)
					return ret;
			}
		}

		ret = ad9467_testmode_set(st, chan->idx, mode);
		if (ret)
			return ret;

		out_mode = st->info->default_output_mode;
		ret = ad9467_outputmode_set(st, out_mode);
		if (ret)
			return ret;
	} else {
		unsigned int cmode;

		cmode = st->info->default_output_mode;
		FIELD_MODIFY(AN877_ADC_OUTPUT_MODE_MASK, &cmode,
			     AN877_ADC_OUTPUT_MODE_OFFSET_BINARY);
		ret = ad9467_outputmode_set(st, cmode);
		if (ret)
			return ret;

		ret = ad9467_testmode_set(st, chan->idx, mode);
		if (ret)
			return ret;

		/*  some patterns have a backend matching monitoring block */
		if (iio_backend_has_caps(st->back, IIO_BACKEND_CAP_CALIBRATION)) {
			if (mode == AN877_ADC_TESTMODE_PN9_SEQ) {
				ret = ad9467_backend_testmode_on(st, chan->idx,
							 IIO_BACKEND_ADI_PRBS_9A);
				if (ret)
					return ret;
			} else if (mode == AN877_ADC_TESTMODE_PN23_SEQ) {
				ret = ad9467_backend_testmode_on(st, chan->idx,
							 IIO_BACKEND_ADI_PRBS_23A);
				if (ret)
					return ret;
			}
		}
	}

	chan->mode = mode;

	return count;
}

static const struct file_operations ad9467_chan_test_mode_fops = {
	.open = simple_open,
	.read = ad9467_chan_test_mode_read,
	.write = ad9467_chan_test_mode_write,
	.llseek = default_llseek,
	.owner = THIS_MODULE,
};

static ssize_t ad9467_dump_calib_table(struct file *file,
				       char __user *userbuf,
				       size_t count, loff_t *ppos)
{
	struct ad9467_state *st = file->private_data;
	unsigned int bit;
	/* +2 for the newline and +1 for the string termination */
	unsigned char map[AD9647_MAX_TEST_POINTS * 2 + 3];
	ssize_t len = 0;

	guard(mutex)(&st->lock);
	if (*ppos)
		goto out_read;

	for (bit = 0; bit < st->calib_map_size; bit++) {
		if (AD9467_CAN_INVERT(st) && bit == st->calib_map_size / 2)
			len += scnprintf(map + len, sizeof(map) - len, "\n");

		len += scnprintf(map + len, sizeof(map) - len, "%c",
				 test_bit(bit, st->calib_map) ? 'x' : 'o');
	}

	len += scnprintf(map + len, sizeof(map) - len, "\n");
out_read:
	return simple_read_from_buffer(userbuf, count, ppos, map, len);
}

static const struct file_operations ad9467_calib_table_fops = {
	.open = simple_open,
	.read = ad9467_dump_calib_table,
	.llseek = default_llseek,
	.owner = THIS_MODULE,
};

static void ad9467_debugfs_init(struct iio_dev *indio_dev)
{
	struct dentry *d = iio_get_debugfs_dentry(indio_dev);
	struct ad9467_state *st = iio_priv(indio_dev);
	char attr_name[32];
	unsigned int chan;

	if (!IS_ENABLED(CONFIG_DEBUG_FS))
		return;

	st->chan_test = devm_kcalloc(&st->spi->dev, st->info->num_channels,
				     sizeof(*st->chan_test), GFP_KERNEL);
	if (!st->chan_test)
		return;

	if (iio_backend_has_caps(st->back, IIO_BACKEND_CAP_CALIBRATION))
		debugfs_create_file("calibration_table_dump", 0400, d, st,
				    &ad9467_calib_table_fops);

	for (chan = 0; chan < st->info->num_channels; chan++) {
		snprintf(attr_name, sizeof(attr_name), "in_voltage%u_test_mode",
			 chan);
		st->chan_test[chan].idx = chan;
		st->chan_test[chan].st = st;
		debugfs_create_file(attr_name, 0600, d, &st->chan_test[chan],
				    &ad9467_chan_test_mode_fops);
	}

	debugfs_create_file("in_voltage_test_mode_available", 0400, d, st,
			    &ad9467_test_mode_available_fops);

	iio_backend_debugfs_add(st->back, indio_dev);
}

static int ad9467_probe(struct spi_device *spi)
{
	struct device *dev = &spi->dev;
	struct iio_dev *indio_dev;
	struct ad9467_state *st;
	unsigned int id;
	int ret;

	indio_dev = devm_iio_device_alloc(dev, sizeof(*st));
	if (!indio_dev)
		return -ENOMEM;

	st = iio_priv(indio_dev);
	st->spi = spi;

	st->info = spi_get_device_match_data(spi);
	if (!st->info)
		return -ENODEV;

	st->calib_map_size = st->info->test_points;
	if (AD9467_CAN_INVERT(st))
		st->calib_map_size *= 2;

	st->clk = devm_clk_get_enabled(dev, "adc-clk");
	if (IS_ERR(st->clk))
		return PTR_ERR(st->clk);

	st->pwrdown_gpio = devm_gpiod_get_optional(dev, "powerdown", GPIOD_OUT_LOW);
	if (IS_ERR(st->pwrdown_gpio))
		return PTR_ERR(st->pwrdown_gpio);

	ret = ad9467_reset(dev);
	if (ret)
		return ret;

	ret = ad9467_scale_fill(st);
	if (ret)
		return ret;

	id = ad9467_spi_read(st, AN877_ADC_REG_CHIP_ID);
	if (id != st->info->id)
		return dev_err_probe(dev, -ENODEV,
				     "Mismatch CHIP_ID, got 0x%X, expected 0x%X\n",
				     id, st->info->id);

	if (st->info->num_scales > 1)
		indio_dev->info = &ad9467_info;
	else
		indio_dev->info = &ad9467_info_no_read_avail;
	indio_dev->name = st->info->name;
	indio_dev->channels = st->info->channels;
	indio_dev->num_channels = st->info->num_channels;

	ret = ad9467_iio_backend_get(st);
	if (ret)
		return ret;

	if (iio_backend_has_caps(st->back, IIO_BACKEND_CAP_BUFFER)) {
		ret = devm_iio_backend_request_buffer(dev, st->back, indio_dev);
		if (ret)
			return ret;
	}

	if (iio_backend_has_caps(st->back, IIO_BACKEND_CAP_ENABLE)) {
		ret = devm_iio_backend_enable(dev, st->back);
		if (ret)
			return ret;
	}

	if (iio_backend_has_caps(st->back, IIO_BACKEND_CAP_CALIBRATION)) {
		ret = ad9467_calibrate(st);
		if (ret)
			return ret;
	}

	ret = devm_iio_device_register(dev, indio_dev);
	if (ret)
		return ret;

	ad9467_debugfs_init(indio_dev);

	return 0;
}

static const struct of_device_id ad9467_of_match[] = {
	{ .compatible = "adi,ad9211", .data = &ad9211_chip_tbl, },
	{ .compatible = "adi,ad9265", .data = &ad9265_chip_tbl, },
	{ .compatible = "adi,ad9434", .data = &ad9434_chip_tbl, },
	{ .compatible = "adi,ad9467", .data = &ad9467_chip_tbl, },
	{ .compatible = "adi,ad9643", .data = &ad9643_chip_tbl, },
	{ .compatible = "adi,ad9649", .data = &ad9649_chip_tbl, },
	{ .compatible = "adi,ad9652", .data = &ad9652_chip_tbl, },
	{ }
};
MODULE_DEVICE_TABLE(of, ad9467_of_match);

static const struct spi_device_id ad9467_ids[] = {
	{ .name = "ad9211", .driver_data = (kernel_ulong_t)&ad9211_chip_tbl },
	{ .name = "ad9265", .driver_data = (kernel_ulong_t)&ad9265_chip_tbl },
	{ .name = "ad9434", .driver_data = (kernel_ulong_t)&ad9434_chip_tbl },
	{ .name = "ad9467", .driver_data = (kernel_ulong_t)&ad9467_chip_tbl },
	{ .name = "ad9643", .driver_data = (kernel_ulong_t)&ad9643_chip_tbl },
	{ .name = "ad9649", .driver_data = (kernel_ulong_t)&ad9649_chip_tbl },
	{ .name = "ad9652", .driver_data = (kernel_ulong_t)&ad9652_chip_tbl },
	{ }
};
MODULE_DEVICE_TABLE(spi, ad9467_ids);

static struct spi_driver ad9467_driver = {
	.driver = {
		.name = "ad9467",
		.of_match_table = ad9467_of_match,
	},
	.probe = ad9467_probe,
	.id_table = ad9467_ids,
};
module_spi_driver(ad9467_driver);

MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
MODULE_DESCRIPTION("Analog Devices AD9467 ADC driver");
MODULE_LICENSE("GPL v2");
MODULE_IMPORT_NS("IIO_BACKEND");