Linux Audio

Check our new training course

Embedded Linux Audio

Check our new training course
with Creative Commons CC-BY-SA
lecture materials

Bootlin logo

Elixir Cross Referencer

Loading...
   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
/**
 * Microchip ENCX24J600 ethernet driver
 *
 * Copyright (C) 2015 Gridpoint
 * Author: Jon Ringle <jringle@gridpoint.com>
 *
 * 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/device.h>
#include <linux/errno.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/regmap.h>
#include <linux/skbuff.h>
#include <linux/spi/spi.h>

#include "encx24j600_hw.h"

#define DRV_NAME	"encx24j600"
#define DRV_VERSION	"1.0"

#define DEFAULT_MSG_ENABLE (NETIF_MSG_DRV | NETIF_MSG_PROBE | NETIF_MSG_LINK)
static int debug = -1;
module_param(debug, int, 0000);
MODULE_PARM_DESC(debug, "Debug level (0=none,...,16=all)");

/* SRAM memory layout:
 *
 * 0x0000-0x05ff TX buffers  1.5KB  (1*1536) reside in the GP area in SRAM
 * 0x0600-0x5fff RX buffers 22.5KB (15*1536) reside in the RX area in SRAM
 */
#define ENC_TX_BUF_START 0x0000U
#define ENC_RX_BUF_START 0x0600U
#define ENC_RX_BUF_END   0x5fffU
#define ENC_SRAM_SIZE    0x6000U

enum {
	RXFILTER_NORMAL,
	RXFILTER_MULTI,
	RXFILTER_PROMISC
};

struct encx24j600_priv {
	struct net_device        *ndev;
	struct mutex              lock; /* device access lock */
	struct encx24j600_context ctx;
	struct sk_buff           *tx_skb;
	struct task_struct       *kworker_task;
	struct kthread_worker     kworker;
	struct kthread_work       tx_work;
	struct kthread_work       setrx_work;
	u16                       next_packet;
	bool                      hw_enabled;
	bool                      full_duplex;
	bool                      autoneg;
	u16                       speed;
	int                       rxfilter;
	u32                       msg_enable;
};

static void dump_packet(const char *msg, int len, const char *data)
{
	pr_debug(DRV_NAME ": %s - packet len:%d\n", msg, len);
	print_hex_dump_bytes("pk data: ", DUMP_PREFIX_OFFSET, data, len);
}

static void encx24j600_dump_rsv(struct encx24j600_priv *priv, const char *msg,
				struct rsv *rsv)
{
	struct net_device *dev = priv->ndev;

	netdev_info(dev, "RX packet Len:%d\n", rsv->len);
	netdev_dbg(dev, "%s - NextPk: 0x%04x\n", msg,
		   rsv->next_packet);
	netdev_dbg(dev, "RxOK: %d, DribbleNibble: %d\n",
		   RSV_GETBIT(rsv->rxstat, RSV_RXOK),
		   RSV_GETBIT(rsv->rxstat, RSV_DRIBBLENIBBLE));
	netdev_dbg(dev, "CRCErr:%d, LenChkErr: %d, LenOutOfRange: %d\n",
		   RSV_GETBIT(rsv->rxstat, RSV_CRCERROR),
		   RSV_GETBIT(rsv->rxstat, RSV_LENCHECKERR),
		   RSV_GETBIT(rsv->rxstat, RSV_LENOUTOFRANGE));
	netdev_dbg(dev, "Multicast: %d, Broadcast: %d, LongDropEvent: %d, CarrierEvent: %d\n",
		   RSV_GETBIT(rsv->rxstat, RSV_RXMULTICAST),
		   RSV_GETBIT(rsv->rxstat, RSV_RXBROADCAST),
		   RSV_GETBIT(rsv->rxstat, RSV_RXLONGEVDROPEV),
		   RSV_GETBIT(rsv->rxstat, RSV_CARRIEREV));
	netdev_dbg(dev, "ControlFrame: %d, PauseFrame: %d, UnknownOp: %d, VLanTagFrame: %d\n",
		   RSV_GETBIT(rsv->rxstat, RSV_RXCONTROLFRAME),
		   RSV_GETBIT(rsv->rxstat, RSV_RXPAUSEFRAME),
		   RSV_GETBIT(rsv->rxstat, RSV_RXUNKNOWNOPCODE),
		   RSV_GETBIT(rsv->rxstat, RSV_RXTYPEVLAN));
}

static u16 encx24j600_read_reg(struct encx24j600_priv *priv, u8 reg)
{
	struct net_device *dev = priv->ndev;
	unsigned int val = 0;
	int ret = regmap_read(priv->ctx.regmap, reg, &val);

	if (unlikely(ret))
		netif_err(priv, drv, dev, "%s: error %d reading reg %02x\n",
			  __func__, ret, reg);
	return val;
}

static void encx24j600_write_reg(struct encx24j600_priv *priv, u8 reg, u16 val)
{
	struct net_device *dev = priv->ndev;
	int ret = regmap_write(priv->ctx.regmap, reg, val);

	if (unlikely(ret))
		netif_err(priv, drv, dev, "%s: error %d writing reg %02x=%04x\n",
			  __func__, ret, reg, val);
}

static void encx24j600_update_reg(struct encx24j600_priv *priv, u8 reg,
				  u16 mask, u16 val)
{
	struct net_device *dev = priv->ndev;
	int ret = regmap_update_bits(priv->ctx.regmap, reg, mask, val);

	if (unlikely(ret))
		netif_err(priv, drv, dev, "%s: error %d updating reg %02x=%04x~%04x\n",
			  __func__, ret, reg, val, mask);
}

static u16 encx24j600_read_phy(struct encx24j600_priv *priv, u8 reg)
{
	struct net_device *dev = priv->ndev;
	unsigned int val = 0;
	int ret = regmap_read(priv->ctx.phymap, reg, &val);

	if (unlikely(ret))
		netif_err(priv, drv, dev, "%s: error %d reading %02x\n",
			  __func__, ret, reg);
	return val;
}

static void encx24j600_write_phy(struct encx24j600_priv *priv, u8 reg, u16 val)
{
	struct net_device *dev = priv->ndev;
	int ret = regmap_write(priv->ctx.phymap, reg, val);

	if (unlikely(ret))
		netif_err(priv, drv, dev, "%s: error %d writing reg %02x=%04x\n",
			  __func__, ret, reg, val);
}

static void encx24j600_clr_bits(struct encx24j600_priv *priv, u8 reg, u16 mask)
{
	encx24j600_update_reg(priv, reg, mask, 0);
}

static void encx24j600_set_bits(struct encx24j600_priv *priv, u8 reg, u16 mask)
{
	encx24j600_update_reg(priv, reg, mask, mask);
}

static void encx24j600_cmd(struct encx24j600_priv *priv, u8 cmd)
{
	struct net_device *dev = priv->ndev;
	int ret = regmap_write(priv->ctx.regmap, cmd, 0);

	if (unlikely(ret))
		netif_err(priv, drv, dev, "%s: error %d with cmd %02x\n",
			  __func__, ret, cmd);
}

static int encx24j600_raw_read(struct encx24j600_priv *priv, u8 reg, u8 *data,
			       size_t count)
{
	int ret;

	mutex_lock(&priv->ctx.mutex);
	ret = regmap_encx24j600_spi_read(&priv->ctx, reg, data, count);
	mutex_unlock(&priv->ctx.mutex);

	return ret;
}

static int encx24j600_raw_write(struct encx24j600_priv *priv, u8 reg,
				const u8 *data, size_t count)
{
	int ret;

	mutex_lock(&priv->ctx.mutex);
	ret = regmap_encx24j600_spi_write(&priv->ctx, reg, data, count);
	mutex_unlock(&priv->ctx.mutex);

	return ret;
}

static void encx24j600_update_phcon1(struct encx24j600_priv *priv)
{
	u16 phcon1 = encx24j600_read_phy(priv, PHCON1);

	if (priv->autoneg == AUTONEG_ENABLE) {
		phcon1 |= ANEN | RENEG;
	} else {
		phcon1 &= ~ANEN;
		if (priv->speed == SPEED_100)
			phcon1 |= SPD100;
		else
			phcon1 &= ~SPD100;

		if (priv->full_duplex)
			phcon1 |= PFULDPX;
		else
			phcon1 &= ~PFULDPX;
	}
	encx24j600_write_phy(priv, PHCON1, phcon1);
}

/* Waits for autonegotiation to complete. */
static int encx24j600_wait_for_autoneg(struct encx24j600_priv *priv)
{
	struct net_device *dev = priv->ndev;
	unsigned long timeout = jiffies + msecs_to_jiffies(2000);
	u16 phstat1;
	u16 estat;
	int ret = 0;

	phstat1 = encx24j600_read_phy(priv, PHSTAT1);
	while ((phstat1 & ANDONE) == 0) {
		if (time_after(jiffies, timeout)) {
			u16 phstat3;

			netif_notice(priv, drv, dev, "timeout waiting for autoneg done\n");

			priv->autoneg = AUTONEG_DISABLE;
			phstat3 = encx24j600_read_phy(priv, PHSTAT3);
			priv->speed = (phstat3 & PHY3SPD100)
				      ? SPEED_100 : SPEED_10;
			priv->full_duplex = (phstat3 & PHY3DPX) ? 1 : 0;
			encx24j600_update_phcon1(priv);
			netif_notice(priv, drv, dev, "Using parallel detection: %s/%s",
				     priv->speed == SPEED_100 ? "100" : "10",
				     priv->full_duplex ? "Full" : "Half");

			return -ETIMEDOUT;
		}
		cpu_relax();
		phstat1 = encx24j600_read_phy(priv, PHSTAT1);
	}

	estat = encx24j600_read_reg(priv, ESTAT);
	if (estat & PHYDPX) {
		encx24j600_set_bits(priv, MACON2, FULDPX);
		encx24j600_write_reg(priv, MABBIPG, 0x15);
	} else {
		encx24j600_clr_bits(priv, MACON2, FULDPX);
		encx24j600_write_reg(priv, MABBIPG, 0x12);
		/* Max retransmittions attempt  */
		encx24j600_write_reg(priv, MACLCON, 0x370f);
	}

	return ret;
}

/* Access the PHY to determine link status */
static void encx24j600_check_link_status(struct encx24j600_priv *priv)
{
	struct net_device *dev = priv->ndev;
	u16 estat;

	estat = encx24j600_read_reg(priv, ESTAT);

	if (estat & PHYLNK) {
		if (priv->autoneg == AUTONEG_ENABLE)
			encx24j600_wait_for_autoneg(priv);

		netif_carrier_on(dev);
		netif_info(priv, ifup, dev, "link up\n");
	} else {
		netif_info(priv, ifdown, dev, "link down\n");

		/* Re-enable autoneg since we won't know what we might be
		 * connected to when the link is brought back up again.
		 */
		priv->autoneg  = AUTONEG_ENABLE;
		priv->full_duplex = true;
		priv->speed = SPEED_100;
		netif_carrier_off(dev);
	}
}

static void encx24j600_int_link_handler(struct encx24j600_priv *priv)
{
	struct net_device *dev = priv->ndev;

	netif_dbg(priv, intr, dev, "%s", __func__);
	encx24j600_check_link_status(priv);
	encx24j600_clr_bits(priv, EIR, LINKIF);
}

static void encx24j600_tx_complete(struct encx24j600_priv *priv, bool err)
{
	struct net_device *dev = priv->ndev;

	if (!priv->tx_skb) {
		BUG();
		return;
	}

	mutex_lock(&priv->lock);

	if (err)
		dev->stats.tx_errors++;
	else
		dev->stats.tx_packets++;

	dev->stats.tx_bytes += priv->tx_skb->len;

	encx24j600_clr_bits(priv, EIR, TXIF | TXABTIF);

	netif_dbg(priv, tx_done, dev, "TX Done%s\n", err ? ": Err" : "");

	dev_kfree_skb(priv->tx_skb);
	priv->tx_skb = NULL;

	netif_wake_queue(dev);

	mutex_unlock(&priv->lock);
}

static int encx24j600_receive_packet(struct encx24j600_priv *priv,
				     struct rsv *rsv)
{
	struct net_device *dev = priv->ndev;
	struct sk_buff *skb = netdev_alloc_skb(dev, rsv->len + NET_IP_ALIGN);

	if (!skb) {
		pr_err_ratelimited("RX: OOM: packet dropped\n");
		dev->stats.rx_dropped++;
		return -ENOMEM;
	}
	skb_reserve(skb, NET_IP_ALIGN);
	encx24j600_raw_read(priv, RRXDATA, skb_put(skb, rsv->len), rsv->len);

	if (netif_msg_pktdata(priv))
		dump_packet("RX", skb->len, skb->data);

	skb->dev = dev;
	skb->protocol = eth_type_trans(skb, dev);
	skb->ip_summed = CHECKSUM_COMPLETE;

	/* Maintain stats */
	dev->stats.rx_packets++;
	dev->stats.rx_bytes += rsv->len;

	netif_rx(skb);

	return 0;
}

static void encx24j600_rx_packets(struct encx24j600_priv *priv, u8 packet_count)
{
	struct net_device *dev = priv->ndev;

	while (packet_count--) {
		struct rsv rsv;
		u16 newrxtail;

		encx24j600_write_reg(priv, ERXRDPT, priv->next_packet);
		encx24j600_raw_read(priv, RRXDATA, (u8 *)&rsv, sizeof(rsv));

		if (netif_msg_rx_status(priv))
			encx24j600_dump_rsv(priv, __func__, &rsv);

		if (!RSV_GETBIT(rsv.rxstat, RSV_RXOK) ||
		    (rsv.len > MAX_FRAMELEN)) {
			netif_err(priv, rx_err, dev, "RX Error %04x\n",
				  rsv.rxstat);
			dev->stats.rx_errors++;

			if (RSV_GETBIT(rsv.rxstat, RSV_CRCERROR))
				dev->stats.rx_crc_errors++;
			if (RSV_GETBIT(rsv.rxstat, RSV_LENCHECKERR))
				dev->stats.rx_frame_errors++;
			if (rsv.len > MAX_FRAMELEN)
				dev->stats.rx_over_errors++;
		} else {
			encx24j600_receive_packet(priv, &rsv);
		}

		priv->next_packet = rsv.next_packet;

		newrxtail = priv->next_packet - 2;
		if (newrxtail == ENC_RX_BUF_START)
			newrxtail = SRAM_SIZE - 2;

		encx24j600_cmd(priv, SETPKTDEC);
		encx24j600_write_reg(priv, ERXTAIL, newrxtail);
	}
}

static irqreturn_t encx24j600_isr(int irq, void *dev_id)
{
	struct encx24j600_priv *priv = dev_id;
	struct net_device *dev = priv->ndev;
	int eir;

	/* Clear interrupts */
	encx24j600_cmd(priv, CLREIE);

	eir = encx24j600_read_reg(priv, EIR);

	if (eir & LINKIF)
		encx24j600_int_link_handler(priv);

	if (eir & TXIF)
		encx24j600_tx_complete(priv, false);

	if (eir & TXABTIF)
		encx24j600_tx_complete(priv, true);

	if (eir & RXABTIF) {
		if (eir & PCFULIF) {
			/* Packet counter is full */
			netif_err(priv, rx_err, dev, "Packet counter full\n");
		}
		dev->stats.rx_dropped++;
		encx24j600_clr_bits(priv, EIR, RXABTIF);
	}

	if (eir & PKTIF) {
		u8 packet_count;

		mutex_lock(&priv->lock);

		packet_count = encx24j600_read_reg(priv, ESTAT) & 0xff;
		while (packet_count) {
			encx24j600_rx_packets(priv, packet_count);
			packet_count = encx24j600_read_reg(priv, ESTAT) & 0xff;
		}

		mutex_unlock(&priv->lock);
	}

	/* Enable interrupts */
	encx24j600_cmd(priv, SETEIE);

	return IRQ_HANDLED;
}

static int encx24j600_soft_reset(struct encx24j600_priv *priv)
{
	int ret = 0;
	int timeout;
	u16 eudast;

	/* Write and verify a test value to EUDAST */
	regcache_cache_bypass(priv->ctx.regmap, true);
	timeout = 10;
	do {
		encx24j600_write_reg(priv, EUDAST, EUDAST_TEST_VAL);
		eudast = encx24j600_read_reg(priv, EUDAST);
		usleep_range(25, 100);
	} while ((eudast != EUDAST_TEST_VAL) && --timeout);
	regcache_cache_bypass(priv->ctx.regmap, false);

	if (timeout == 0) {
		ret = -ETIMEDOUT;
		goto err_out;
	}

	/* Wait for CLKRDY to become set */
	timeout = 10;
	while (!(encx24j600_read_reg(priv, ESTAT) & CLKRDY) && --timeout)
		usleep_range(25, 100);

	if (timeout == 0) {
		ret = -ETIMEDOUT;
		goto err_out;
	}

	/* Issue a System Reset command */
	encx24j600_cmd(priv, SETETHRST);
	usleep_range(25, 100);

	/* Confirm that EUDAST has 0000h after system reset */
	if (encx24j600_read_reg(priv, EUDAST) != 0) {
		ret = -EINVAL;
		goto err_out;
	}

	/* Wait for PHY register and status bits to become available */
	usleep_range(256, 1000);

err_out:
	return ret;
}

static int encx24j600_hw_reset(struct encx24j600_priv *priv)
{
	int ret;

	mutex_lock(&priv->lock);
	ret = encx24j600_soft_reset(priv);
	mutex_unlock(&priv->lock);

	return ret;
}

static void encx24j600_reset_hw_tx(struct encx24j600_priv *priv)
{
	encx24j600_set_bits(priv, ECON2, TXRST);
	encx24j600_clr_bits(priv, ECON2, TXRST);
}

static void encx24j600_hw_init_tx(struct encx24j600_priv *priv)
{
	/* Reset TX */
	encx24j600_reset_hw_tx(priv);

	/* Clear the TXIF flag if were previously set */
	encx24j600_clr_bits(priv, EIR, TXIF | TXABTIF);

	/* Write the Tx Buffer pointer */
	encx24j600_write_reg(priv, EGPWRPT, ENC_TX_BUF_START);
}

static void encx24j600_hw_init_rx(struct encx24j600_priv *priv)
{
	encx24j600_cmd(priv, DISABLERX);

	/* Set up RX packet start address in the SRAM */
	encx24j600_write_reg(priv, ERXST, ENC_RX_BUF_START);

	/* Preload the RX Data pointer to the beginning of the RX area */
	encx24j600_write_reg(priv, ERXRDPT, ENC_RX_BUF_START);

	priv->next_packet = ENC_RX_BUF_START;

	/* Set up RX end address in the SRAM */
	encx24j600_write_reg(priv, ERXTAIL, ENC_SRAM_SIZE - 2);

	/* Reset the  user data pointers    */
	encx24j600_write_reg(priv, EUDAST, ENC_SRAM_SIZE);
	encx24j600_write_reg(priv, EUDAND, ENC_SRAM_SIZE + 1);

	/* Set Max Frame length */
	encx24j600_write_reg(priv, MAMXFL, MAX_FRAMELEN);
}

static void encx24j600_dump_config(struct encx24j600_priv *priv,
				   const char *msg)
{
	pr_info(DRV_NAME ": %s\n", msg);

	/* CHIP configuration */
	pr_info(DRV_NAME " ECON1:   %04X\n", encx24j600_read_reg(priv, ECON1));
	pr_info(DRV_NAME " ECON2:   %04X\n", encx24j600_read_reg(priv, ECON2));
	pr_info(DRV_NAME " ERXFCON: %04X\n", encx24j600_read_reg(priv,
								 ERXFCON));
	pr_info(DRV_NAME " ESTAT:   %04X\n", encx24j600_read_reg(priv, ESTAT));
	pr_info(DRV_NAME " EIR:     %04X\n", encx24j600_read_reg(priv, EIR));
	pr_info(DRV_NAME " EIDLED:  %04X\n", encx24j600_read_reg(priv, EIDLED));

	/* MAC layer configuration */
	pr_info(DRV_NAME " MACON1:  %04X\n", encx24j600_read_reg(priv, MACON1));
	pr_info(DRV_NAME " MACON2:  %04X\n", encx24j600_read_reg(priv, MACON2));
	pr_info(DRV_NAME " MAIPG:   %04X\n", encx24j600_read_reg(priv, MAIPG));
	pr_info(DRV_NAME " MACLCON: %04X\n", encx24j600_read_reg(priv,
								 MACLCON));
	pr_info(DRV_NAME " MABBIPG: %04X\n", encx24j600_read_reg(priv,
								 MABBIPG));

	/* PHY configuation */
	pr_info(DRV_NAME " PHCON1:  %04X\n", encx24j600_read_phy(priv, PHCON1));
	pr_info(DRV_NAME " PHCON2:  %04X\n", encx24j600_read_phy(priv, PHCON2));
	pr_info(DRV_NAME " PHANA:   %04X\n", encx24j600_read_phy(priv, PHANA));
	pr_info(DRV_NAME " PHANLPA: %04X\n", encx24j600_read_phy(priv,
								 PHANLPA));
	pr_info(DRV_NAME " PHANE:   %04X\n", encx24j600_read_phy(priv, PHANE));
	pr_info(DRV_NAME " PHSTAT1: %04X\n", encx24j600_read_phy(priv,
								 PHSTAT1));
	pr_info(DRV_NAME " PHSTAT2: %04X\n", encx24j600_read_phy(priv,
								 PHSTAT2));
	pr_info(DRV_NAME " PHSTAT3: %04X\n", encx24j600_read_phy(priv,
								 PHSTAT3));
}

static void encx24j600_set_rxfilter_mode(struct encx24j600_priv *priv)
{
	switch (priv->rxfilter) {
	case RXFILTER_PROMISC:
		encx24j600_set_bits(priv, MACON1, PASSALL);
		encx24j600_write_reg(priv, ERXFCON, UCEN | MCEN | NOTMEEN);
		break;
	case RXFILTER_MULTI:
		encx24j600_clr_bits(priv, MACON1, PASSALL);
		encx24j600_write_reg(priv, ERXFCON, UCEN | CRCEN | BCEN | MCEN);
		break;
	case RXFILTER_NORMAL:
	default:
		encx24j600_clr_bits(priv, MACON1, PASSALL);
		encx24j600_write_reg(priv, ERXFCON, UCEN | CRCEN | BCEN);
		break;
	}
}

static int encx24j600_hw_init(struct encx24j600_priv *priv)
{
	int ret = 0;
	u16 macon2;

	priv->hw_enabled = false;

	/* PHY Leds: link status,
	 * LEDA: Link State + collision events
	 * LEDB: Link State + transmit/receive events
	 */
	encx24j600_update_reg(priv, EIDLED, 0xff00, 0xcb00);

	/* Loopback disabled */
	encx24j600_write_reg(priv, MACON1, 0x9);

	/* interpacket gap value */
	encx24j600_write_reg(priv, MAIPG, 0x0c12);

	/* Write the auto negotiation pattern */
	encx24j600_write_phy(priv, PHANA, PHANA_DEFAULT);

	encx24j600_update_phcon1(priv);
	encx24j600_check_link_status(priv);

	macon2 = MACON2_RSV1 | TXCRCEN | PADCFG0 | PADCFG2 | MACON2_DEFER;
	if ((priv->autoneg == AUTONEG_DISABLE) && priv->full_duplex)
		macon2 |= FULDPX;

	encx24j600_set_bits(priv, MACON2, macon2);

	priv->rxfilter = RXFILTER_NORMAL;
	encx24j600_set_rxfilter_mode(priv);

	/* Program the Maximum frame length */
	encx24j600_write_reg(priv, MAMXFL, MAX_FRAMELEN);

	/* Init Tx pointers */
	encx24j600_hw_init_tx(priv);

	/* Init Rx pointers */
	encx24j600_hw_init_rx(priv);

	if (netif_msg_hw(priv))
		encx24j600_dump_config(priv, "Hw is initialized");

	return ret;
}

static void encx24j600_hw_enable(struct encx24j600_priv *priv)
{
	/* Clear the interrupt flags in case was set */
	encx24j600_clr_bits(priv, EIR, (PCFULIF | RXABTIF | TXABTIF | TXIF |
					PKTIF | LINKIF));

	/* Enable the interrupts */
	encx24j600_write_reg(priv, EIE, (PCFULIE | RXABTIE | TXABTIE | TXIE |
					 PKTIE | LINKIE | INTIE));

	/* Enable RX */
	encx24j600_cmd(priv, ENABLERX);

	priv->hw_enabled = true;
}

static void encx24j600_hw_disable(struct encx24j600_priv *priv)
{
	/* Disable all interrupts */
	encx24j600_write_reg(priv, EIE, 0);

	/* Disable RX */
	encx24j600_cmd(priv, DISABLERX);

	priv->hw_enabled = false;
}

static int encx24j600_setlink(struct net_device *dev, u8 autoneg, u16 speed,
			      u8 duplex)
{
	struct encx24j600_priv *priv = netdev_priv(dev);
	int ret = 0;

	if (!priv->hw_enabled) {
		/* link is in low power mode now; duplex setting
		 * will take effect on next encx24j600_hw_init()
		 */
		if (speed == SPEED_10 || speed == SPEED_100) {
			priv->autoneg = (autoneg == AUTONEG_ENABLE);
			priv->full_duplex = (duplex == DUPLEX_FULL);
			priv->speed = (speed == SPEED_100);
		} else {
			netif_warn(priv, link, dev, "unsupported link speed setting\n");
			/*speeds other than SPEED_10 and SPEED_100 */
			/*are not supported by chip */
			ret = -EOPNOTSUPP;
		}
	} else {
		netif_warn(priv, link, dev, "Warning: hw must be disabled to set link mode\n");
		ret = -EBUSY;
	}
	return ret;
}

static void encx24j600_hw_get_macaddr(struct encx24j600_priv *priv,
				      unsigned char *ethaddr)
{
	unsigned short val;

	val = encx24j600_read_reg(priv, MAADR1);

	ethaddr[0] = val & 0x00ff;
	ethaddr[1] = (val & 0xff00) >> 8;

	val = encx24j600_read_reg(priv, MAADR2);

	ethaddr[2] = val & 0x00ffU;
	ethaddr[3] = (val & 0xff00U) >> 8;

	val = encx24j600_read_reg(priv, MAADR3);

	ethaddr[4] = val & 0x00ffU;
	ethaddr[5] = (val & 0xff00U) >> 8;
}

/* Program the hardware MAC address from dev->dev_addr.*/
static int encx24j600_set_hw_macaddr(struct net_device *dev)
{
	struct encx24j600_priv *priv = netdev_priv(dev);

	if (priv->hw_enabled) {
		netif_info(priv, drv, dev, "Hardware must be disabled to set Mac address\n");
		return -EBUSY;
	}

	mutex_lock(&priv->lock);

	netif_info(priv, drv, dev, "%s: Setting MAC address to %pM\n",
		   dev->name, dev->dev_addr);

	encx24j600_write_reg(priv, MAADR3, (dev->dev_addr[4] |
			     dev->dev_addr[5] << 8));
	encx24j600_write_reg(priv, MAADR2, (dev->dev_addr[2] |
			     dev->dev_addr[3] << 8));
	encx24j600_write_reg(priv, MAADR1, (dev->dev_addr[0] |
			     dev->dev_addr[1] << 8));

	mutex_unlock(&priv->lock);

	return 0;
}

/* Store the new hardware address in dev->dev_addr, and update the MAC.*/
static int encx24j600_set_mac_address(struct net_device *dev, void *addr)
{
	struct sockaddr *address = addr;

	if (netif_running(dev))
		return -EBUSY;
	if (!is_valid_ether_addr(address->sa_data))
		return -EADDRNOTAVAIL;

	memcpy(dev->dev_addr, address->sa_data, dev->addr_len);
	return encx24j600_set_hw_macaddr(dev);
}

static int encx24j600_open(struct net_device *dev)
{
	struct encx24j600_priv *priv = netdev_priv(dev);

	int ret = request_threaded_irq(priv->ctx.spi->irq, NULL, encx24j600_isr,
				       IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
				       DRV_NAME, priv);
	if (unlikely(ret < 0)) {
		netdev_err(dev, "request irq %d failed (ret = %d)\n",
			   priv->ctx.spi->irq, ret);
		return ret;
	}

	encx24j600_hw_disable(priv);
	encx24j600_hw_init(priv);
	encx24j600_hw_enable(priv);
	netif_start_queue(dev);

	return 0;
}

static int encx24j600_stop(struct net_device *dev)
{
	struct encx24j600_priv *priv = netdev_priv(dev);

	netif_stop_queue(dev);
	free_irq(priv->ctx.spi->irq, priv);
	return 0;
}

static void encx24j600_setrx_proc(struct kthread_work *ws)
{
	struct encx24j600_priv *priv =
			container_of(ws, struct encx24j600_priv, setrx_work);

	mutex_lock(&priv->lock);
	encx24j600_set_rxfilter_mode(priv);
	mutex_unlock(&priv->lock);
}

static void encx24j600_set_multicast_list(struct net_device *dev)
{
	struct encx24j600_priv *priv = netdev_priv(dev);
	int oldfilter = priv->rxfilter;

	if (dev->flags & IFF_PROMISC) {
		netif_dbg(priv, link, dev, "promiscuous mode\n");
		priv->rxfilter = RXFILTER_PROMISC;
	} else if ((dev->flags & IFF_ALLMULTI) || !netdev_mc_empty(dev)) {
		netif_dbg(priv, link, dev, "%smulticast mode\n",
			  (dev->flags & IFF_ALLMULTI) ? "all-" : "");
		priv->rxfilter = RXFILTER_MULTI;
	} else {
		netif_dbg(priv, link, dev, "normal mode\n");
		priv->rxfilter = RXFILTER_NORMAL;
	}

	if (oldfilter != priv->rxfilter)
		kthread_queue_work(&priv->kworker, &priv->setrx_work);
}

static void encx24j600_hw_tx(struct encx24j600_priv *priv)
{
	struct net_device *dev = priv->ndev;

	netif_info(priv, tx_queued, dev, "TX Packet Len:%d\n",
		   priv->tx_skb->len);

	if (netif_msg_pktdata(priv))
		dump_packet("TX", priv->tx_skb->len, priv->tx_skb->data);

	if (encx24j600_read_reg(priv, EIR) & TXABTIF)
		/* Last transmition aborted due to error. Reset TX interface */
		encx24j600_reset_hw_tx(priv);

	/* Clear the TXIF flag if were previously set */
	encx24j600_clr_bits(priv, EIR, TXIF);

	/* Set the data pointer to the TX buffer address in the SRAM */
	encx24j600_write_reg(priv, EGPWRPT, ENC_TX_BUF_START);

	/* Copy the packet into the SRAM */
	encx24j600_raw_write(priv, WGPDATA, (u8 *)priv->tx_skb->data,
			     priv->tx_skb->len);

	/* Program the Tx buffer start pointer */
	encx24j600_write_reg(priv, ETXST, ENC_TX_BUF_START);

	/* Program the packet length */
	encx24j600_write_reg(priv, ETXLEN, priv->tx_skb->len);

	/* Start the transmission */
	encx24j600_cmd(priv, SETTXRTS);
}

static void encx24j600_tx_proc(struct kthread_work *ws)
{
	struct encx24j600_priv *priv =
			container_of(ws, struct encx24j600_priv, tx_work);

	mutex_lock(&priv->lock);
	encx24j600_hw_tx(priv);
	mutex_unlock(&priv->lock);
}

static netdev_tx_t encx24j600_tx(struct sk_buff *skb, struct net_device *dev)
{
	struct encx24j600_priv *priv = netdev_priv(dev);

	netif_stop_queue(dev);

	/* save the timestamp */
	netif_trans_update(dev);

	/* Remember the skb for deferred processing */
	priv->tx_skb = skb;

	kthread_queue_work(&priv->kworker, &priv->tx_work);

	return NETDEV_TX_OK;
}

/* Deal with a transmit timeout */
static void encx24j600_tx_timeout(struct net_device *dev)
{
	struct encx24j600_priv *priv = netdev_priv(dev);

	netif_err(priv, tx_err, dev, "TX timeout at %ld, latency %ld\n",
		  jiffies, jiffies - dev_trans_start(dev));

	dev->stats.tx_errors++;
	netif_wake_queue(dev);
}

static int encx24j600_get_regs_len(struct net_device *dev)
{
	return SFR_REG_COUNT;
}

static void encx24j600_get_regs(struct net_device *dev,
				struct ethtool_regs *regs, void *p)
{
	struct encx24j600_priv *priv = netdev_priv(dev);
	u16 *buff = p;
	u8 reg;

	regs->version = 1;
	mutex_lock(&priv->lock);
	for (reg = 0; reg < SFR_REG_COUNT; reg += 2) {
		unsigned int val = 0;
		/* ignore errors for unreadable registers */
		regmap_read(priv->ctx.regmap, reg, &val);
		buff[reg] = val & 0xffff;
	}
	mutex_unlock(&priv->lock);
}

static void encx24j600_get_drvinfo(struct net_device *dev,
				   struct ethtool_drvinfo *info)
{
	strlcpy(info->driver, DRV_NAME, sizeof(info->driver));
	strlcpy(info->version, DRV_VERSION, sizeof(info->version));
	strlcpy(info->bus_info, dev_name(dev->dev.parent),
		sizeof(info->bus_info));
}

static int encx24j600_get_link_ksettings(struct net_device *dev,
					 struct ethtool_link_ksettings *cmd)
{
	struct encx24j600_priv *priv = netdev_priv(dev);
	u32 supported;

	supported = SUPPORTED_10baseT_Half | SUPPORTED_10baseT_Full |
			 SUPPORTED_100baseT_Half | SUPPORTED_100baseT_Full |
			 SUPPORTED_Autoneg | SUPPORTED_TP;

	ethtool_convert_legacy_u32_to_link_mode(cmd->link_modes.supported,
						supported);

	cmd->base.speed = priv->speed;
	cmd->base.duplex = priv->full_duplex ? DUPLEX_FULL : DUPLEX_HALF;
	cmd->base.port = PORT_TP;
	cmd->base.autoneg = priv->autoneg ? AUTONEG_ENABLE : AUTONEG_DISABLE;

	return 0;
}

static int
encx24j600_set_link_ksettings(struct net_device *dev,
			      const struct ethtool_link_ksettings *cmd)
{
	return encx24j600_setlink(dev, cmd->base.autoneg,
				  cmd->base.speed, cmd->base.duplex);
}

static u32 encx24j600_get_msglevel(struct net_device *dev)
{
	struct encx24j600_priv *priv = netdev_priv(dev);

	return priv->msg_enable;
}

static void encx24j600_set_msglevel(struct net_device *dev, u32 val)
{
	struct encx24j600_priv *priv = netdev_priv(dev);

	priv->msg_enable = val;
}

static const struct ethtool_ops encx24j600_ethtool_ops = {
	.get_drvinfo = encx24j600_get_drvinfo,
	.get_msglevel = encx24j600_get_msglevel,
	.set_msglevel = encx24j600_set_msglevel,
	.get_regs_len = encx24j600_get_regs_len,
	.get_regs = encx24j600_get_regs,
	.get_link_ksettings = encx24j600_get_link_ksettings,
	.set_link_ksettings = encx24j600_set_link_ksettings,
};

static const struct net_device_ops encx24j600_netdev_ops = {
	.ndo_open = encx24j600_open,
	.ndo_stop = encx24j600_stop,
	.ndo_start_xmit = encx24j600_tx,
	.ndo_set_rx_mode = encx24j600_set_multicast_list,
	.ndo_set_mac_address = encx24j600_set_mac_address,
	.ndo_tx_timeout = encx24j600_tx_timeout,
	.ndo_validate_addr = eth_validate_addr,
};

static int encx24j600_spi_probe(struct spi_device *spi)
{
	int ret;

	struct net_device *ndev;
	struct encx24j600_priv *priv;
	u16 eidled;

	ndev = alloc_etherdev(sizeof(struct encx24j600_priv));

	if (!ndev) {
		ret = -ENOMEM;
		goto error_out;
	}

	priv = netdev_priv(ndev);
	spi_set_drvdata(spi, priv);
	dev_set_drvdata(&spi->dev, priv);
	SET_NETDEV_DEV(ndev, &spi->dev);

	priv->msg_enable = netif_msg_init(debug, DEFAULT_MSG_ENABLE);
	priv->ndev = ndev;

	/* Default configuration PHY configuration */
	priv->full_duplex = true;
	priv->autoneg = AUTONEG_ENABLE;
	priv->speed = SPEED_100;

	priv->ctx.spi = spi;
	devm_regmap_init_encx24j600(&spi->dev, &priv->ctx);
	ndev->irq = spi->irq;
	ndev->netdev_ops = &encx24j600_netdev_ops;

	mutex_init(&priv->lock);

	/* Reset device and check if it is connected */
	if (encx24j600_hw_reset(priv)) {
		netif_err(priv, probe, ndev,
			  DRV_NAME ": Chip is not detected\n");
		ret = -EIO;
		goto out_free;
	}

	/* Initialize the device HW to the consistent state */
	if (encx24j600_hw_init(priv)) {
		netif_err(priv, probe, ndev,
			  DRV_NAME ": HW initialization error\n");
		ret = -EIO;
		goto out_free;
	}

	kthread_init_worker(&priv->kworker);
	kthread_init_work(&priv->tx_work, encx24j600_tx_proc);
	kthread_init_work(&priv->setrx_work, encx24j600_setrx_proc);

	priv->kworker_task = kthread_run(kthread_worker_fn, &priv->kworker,
					 "encx24j600");

	if (IS_ERR(priv->kworker_task)) {
		ret = PTR_ERR(priv->kworker_task);
		goto out_free;
	}

	/* Get the MAC address from the chip */
	encx24j600_hw_get_macaddr(priv, ndev->dev_addr);

	ndev->ethtool_ops = &encx24j600_ethtool_ops;

	ret = register_netdev(ndev);
	if (unlikely(ret)) {
		netif_err(priv, probe, ndev, "Error %d initializing card encx24j600 card\n",
			  ret);
		goto out_free;
	}

	eidled = encx24j600_read_reg(priv, EIDLED);
	if (((eidled & DEVID_MASK) >> DEVID_SHIFT) != ENCX24J600_DEV_ID) {
		ret = -EINVAL;
		goto out_unregister;
	}

	netif_info(priv, probe, ndev, "Silicon rev ID: 0x%02x\n",
		   (eidled & REVID_MASK) >> REVID_SHIFT);

	netif_info(priv, drv, priv->ndev, "MAC address %pM\n", ndev->dev_addr);

	return ret;

out_unregister:
	unregister_netdev(priv->ndev);
out_free:
	free_netdev(ndev);

error_out:
	return ret;
}

static int encx24j600_spi_remove(struct spi_device *spi)
{
	struct encx24j600_priv *priv = dev_get_drvdata(&spi->dev);

	unregister_netdev(priv->ndev);

	free_netdev(priv->ndev);

	return 0;
}

static const struct spi_device_id encx24j600_spi_id_table[] = {
	{ .name = "encx24j600" },
	{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(spi, encx24j600_spi_id_table);

static struct spi_driver encx24j600_spi_net_driver = {
	.driver = {
		.name	= DRV_NAME,
		.owner	= THIS_MODULE,
		.bus	= &spi_bus_type,
	},
	.probe		= encx24j600_spi_probe,
	.remove		= encx24j600_spi_remove,
	.id_table	= encx24j600_spi_id_table,
};

static int __init encx24j600_init(void)
{
	return spi_register_driver(&encx24j600_spi_net_driver);
}
module_init(encx24j600_init);

static void encx24j600_exit(void)
{
	spi_unregister_driver(&encx24j600_spi_net_driver);
}
module_exit(encx24j600_exit);

MODULE_DESCRIPTION(DRV_NAME " ethernet driver");
MODULE_AUTHOR("Jon Ringle <jringle@gridpoint.com>");
MODULE_LICENSE("GPL");
MODULE_ALIAS("spi:" DRV_NAME);