aboutsummaryrefslogtreecommitdiff
path: root/drivers/net/ethernet/micrel/ks8842.c
blob: 24fb049ac2f28fd7f3c71559fdb3f96559eba495 (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
/*
 * ks8842.c timberdale KS8842 ethernet driver
 * Copyright (c) 2009 Intel Corporation
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

/* Supports:
 * The Micrel KS8842 behind the timberdale FPGA
 * The genuine Micrel KS8841/42 device with ISA 16/32bit bus interface
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/ks8842.h>
#include <linux/dmaengine.h>
#include <linux/dma-mapping.h>
#include <linux/scatterlist.h>

#define DRV_NAME "ks8842"

/* Timberdale specific Registers */
#define REG_TIMB_RST		0x1c
#define REG_TIMB_FIFO		0x20
#define REG_TIMB_ISR		0x24
#define REG_TIMB_IER		0x28
#define REG_TIMB_IAR		0x2C
#define REQ_TIMB_DMA_RESUME	0x30

/* KS8842 registers */

#define REG_SELECT_BANK 0x0e

/* bank 0 registers */
#define REG_QRFCR	0x04

/* bank 2 registers */
#define REG_MARL	0x00
#define REG_MARM	0x02
#define REG_MARH	0x04

/* bank 3 registers */
#define REG_GRR		0x06

/* bank 16 registers */
#define REG_TXCR	0x00
#define REG_TXSR	0x02
#define REG_RXCR	0x04
#define REG_TXMIR	0x08
#define REG_RXMIR	0x0A

/* bank 17 registers */
#define REG_TXQCR	0x00
#define REG_RXQCR	0x02
#define REG_TXFDPR	0x04
#define REG_RXFDPR	0x06
#define REG_QMU_DATA_LO 0x08
#define REG_QMU_DATA_HI 0x0A

/* bank 18 registers */
#define REG_IER		0x00
#define IRQ_LINK_CHANGE	0x8000
#define IRQ_TX		0x4000
#define IRQ_RX		0x2000
#define IRQ_RX_OVERRUN	0x0800
#define IRQ_TX_STOPPED	0x0200
#define IRQ_RX_STOPPED	0x0100
#define IRQ_RX_ERROR	0x0080
#define ENABLED_IRQS	(IRQ_LINK_CHANGE | IRQ_TX | IRQ_RX | IRQ_RX_STOPPED | \
		IRQ_TX_STOPPED | IRQ_RX_OVERRUN | IRQ_RX_ERROR)
/* When running via timberdale in DMA mode, the RX interrupt should be
   enabled in the KS8842, but not in the FPGA IP, since the IP handles
   RX DMA internally.
   TX interrupts are not needed it is handled by the FPGA the driver is
   notified via DMA callbacks.
*/
#define ENABLED_IRQS_DMA_IP	(IRQ_LINK_CHANGE | IRQ_RX_STOPPED | \
	IRQ_TX_STOPPED | IRQ_RX_OVERRUN | IRQ_RX_ERROR)
#define ENABLED_IRQS_DMA	(ENABLED_IRQS_DMA_IP | IRQ_RX)
#define REG_ISR		0x02
#define REG_RXSR	0x04
#define RXSR_VALID	0x8000
#define RXSR_BROADCAST	0x80
#define RXSR_MULTICAST	0x40
#define RXSR_UNICAST	0x20
#define RXSR_FRAMETYPE	0x08
#define RXSR_TOO_LONG	0x04
#define RXSR_RUNT	0x02
#define RXSR_CRC_ERROR	0x01
#define RXSR_ERROR	(RXSR_TOO_LONG | RXSR_RUNT | RXSR_CRC_ERROR)

/* bank 32 registers */
#define REG_SW_ID_AND_ENABLE	0x00
#define REG_SGCR1		0x02
#define REG_SGCR2		0x04
#define REG_SGCR3		0x06

/* bank 39 registers */
#define REG_MACAR1		0x00
#define REG_MACAR2		0x02
#define REG_MACAR3		0x04

/* bank 45 registers */
#define REG_P1MBCR		0x00
#define REG_P1MBSR		0x02

/* bank 46 registers */
#define REG_P2MBCR		0x00
#define REG_P2MBSR		0x02

/* bank 48 registers */
#define REG_P1CR2		0x02

/* bank 49 registers */
#define REG_P1CR4		0x02
#define REG_P1SR		0x04

/* flags passed by platform_device for configuration */
#define	MICREL_KS884X		0x01	/* 0=Timeberdale(FPGA), 1=Micrel */
#define	KS884X_16BIT		0x02	/*  1=16bit, 0=32bit */

#define DMA_BUFFER_SIZE		2048

struct ks8842_tx_dma_ctl {
	struct dma_chan *chan;
	struct dma_async_tx_descriptor *adesc;
	void *buf;
	struct scatterlist sg;
	int channel;
};

struct ks8842_rx_dma_ctl {
	struct dma_chan *chan;
	struct dma_async_tx_descriptor *adesc;
	struct sk_buff  *skb;
	struct scatterlist sg;
	struct tasklet_struct tasklet;
	int channel;
};

#define KS8842_USE_DMA(adapter) (((adapter)->dma_tx.channel != -1) && \
	 ((adapter)->dma_rx.channel != -1))

struct ks8842_adapter {
	void __iomem	*hw_addr;
	int		irq;
	unsigned long	conf_flags;	/* copy of platform_device config */
	struct tasklet_struct	tasklet;
	spinlock_t	lock; /* spinlock to be interrupt safe */
	struct work_struct timeout_work;
	struct net_device *netdev;
	struct device *dev;
	struct ks8842_tx_dma_ctl	dma_tx;
	struct ks8842_rx_dma_ctl	dma_rx;
};

static void ks8842_dma_rx_cb(void *data);
static void ks8842_dma_tx_cb(void *data);

static inline void ks8842_resume_dma(struct ks8842_adapter *adapter)
{
	iowrite32(1, adapter->hw_addr + REQ_TIMB_DMA_RESUME);
}

static inline void ks8842_select_bank(struct ks8842_adapter *adapter, u16 bank)
{
	iowrite16(bank, adapter->hw_addr + REG_SELECT_BANK);
}

static inline void ks8842_write8(struct ks8842_adapter *adapter, u16 bank,
	u8 value, int offset)
{
	ks8842_select_bank(adapter, bank);
	iowrite8(value, adapter->hw_addr + offset);
}

static inline void ks8842_write16(struct ks8842_adapter *adapter, u16 bank,
	u16 value, int offset)
{
	ks8842_select_bank(adapter, bank);
	iowrite16(value, adapter->hw_addr + offset);
}

static inline void ks8842_enable_bits(struct ks8842_adapter *adapter, u16 bank,
	u16 bits, int offset)
{
	u16 reg;
	ks8842_select_bank(adapter, bank);
	reg = ioread16(adapter->hw_addr + offset);
	reg |= bits;
	iowrite16(reg, adapter->hw_addr + offset);
}

static inline void ks8842_clear_bits(struct ks8842_adapter *adapter, u16 bank,
	u16 bits, int offset)
{
	u16 reg;
	ks8842_select_bank(adapter, bank);
	reg = ioread16(adapter->hw_addr + offset);
	reg &= ~bits;
	iowrite16(reg, adapter->hw_addr + offset);
}

static inline void ks8842_write32(struct ks8842_adapter *adapter, u16 bank,
	u32 value, int offset)
{
	ks8842_select_bank(adapter, bank);
	iowrite32(value, adapter->hw_addr + offset);
}

static inline u8 ks8842_read8(struct ks8842_adapter *adapter, u16 bank,
	int offset)
{
	ks8842_select_bank(adapter, bank);
	return ioread8(adapter->hw_addr + offset);
}

static inline u16 ks8842_read16(struct ks8842_adapter *adapter, u16 bank,
	int offset)
{
	ks8842_select_bank(adapter, bank);
	return ioread16(adapter->hw_addr + offset);
}

static inline u32 ks8842_read32(struct ks8842_adapter *adapter, u16 bank,
	int offset)
{
	ks8842_select_bank(adapter, bank);
	return ioread32(adapter->hw_addr + offset);
}

static void ks8842_reset(struct ks8842_adapter *adapter)
{
	if (adapter->conf_flags & MICREL_KS884X) {
		ks8842_write16(adapter, 3, 1, REG_GRR);
		msleep(10);
		iowrite16(0, adapter->hw_addr + REG_GRR);
	} else {
		/* The KS8842 goes haywire when doing softare reset
		* a work around in the timberdale IP is implemented to
		* do a hardware reset instead
		ks8842_write16(adapter, 3, 1, REG_GRR);
		msleep(10);
		iowrite16(0, adapter->hw_addr + REG_GRR);
		*/
		iowrite32(0x1, adapter->hw_addr + REG_TIMB_RST);
		msleep(20);
	}
}

static void ks8842_update_link_status(struct net_device *netdev,
	struct ks8842_adapter *adapter)
{
	/* check the status of the link */
	if (ks8842_read16(adapter, 45, REG_P1MBSR) & 0x4) {
		netif_carrier_on(netdev);
		netif_wake_queue(netdev);
	} else {
		netif_stop_queue(netdev);
		netif_carrier_off(netdev);
	}
}

static void ks8842_enable_tx(struct ks8842_adapter *adapter)
{
	ks8842_enable_bits(adapter, 16, 0x01, REG_TXCR);
}

static void ks8842_disable_tx(struct ks8842_adapter *adapter)
{
	ks8842_clear_bits(adapter, 16, 0x01, REG_TXCR);
}

static void ks8842_enable_rx(struct ks8842_adapter *adapter)
{
	ks8842_enable_bits(adapter, 16, 0x01, REG_RXCR);
}

static void ks8842_disable_rx(struct ks8842_adapter *adapter)
{
	ks8842_clear_bits(adapter, 16, 0x01, REG_RXCR);
}

static void ks8842_reset_hw(struct ks8842_adapter *adapter)
{
	/* reset the HW */
	ks8842_reset(adapter);

	/* Enable QMU Transmit flow control / transmit padding / Transmit CRC */
	ks8842_write16(adapter, 16, 0x000E, REG_TXCR);

	/* enable the receiver, uni + multi + broadcast + flow ctrl
		+ crc strip */
	ks8842_write16(adapter, 16, 0x8 | 0x20 | 0x40 | 0x80 | 0x400,
		REG_RXCR);

	/* TX frame pointer autoincrement */
	ks8842_write16(adapter, 17, 0x4000, REG_TXFDPR);

	/* RX frame pointer autoincrement */
	ks8842_write16(adapter, 17, 0x4000, REG_RXFDPR);

	/* RX 2 kb high watermark */
	ks8842_write16(adapter, 0, 0x1000, REG_QRFCR);

	/* aggressive back off in half duplex */
	ks8842_enable_bits(adapter, 32, 1 << 8, REG_SGCR1);

	/* enable no excessive collison drop */
	ks8842_enable_bits(adapter, 32, 1 << 3, REG_SGCR2);

	/* Enable port 1 force flow control / back pressure / transmit / recv */
	ks8842_write16(adapter, 48, 0x1E07, REG_P1CR2);

	/* restart port auto-negotiation */
	ks8842_enable_bits(adapter, 49, 1 << 13, REG_P1CR4);

	/* Enable the transmitter */
	ks8842_enable_tx(adapter);

	/* Enable the receiver */
	ks8842_enable_rx(adapter);

	/* clear all interrupts */
	ks8842_write16(adapter, 18, 0xffff, REG_ISR);

	/* enable interrupts */
	if (KS8842_USE_DMA(adapter)) {
		/* When running in DMA Mode the RX interrupt is not enabled in
		   timberdale because RX data is received by DMA callbacks
		   it must still be enabled in the KS8842 because it indicates
		   to timberdale when there is RX data for it's DMA FIFOs */
		iowrite16(ENABLED_IRQS_DMA_IP, adapter->hw_addr + REG_TIMB_IER);
		ks8842_write16(adapter, 18, ENABLED_IRQS_DMA, REG_IER);
	} else {
		if (!(adapter->conf_flags & MICREL_KS884X))
			iowrite16(ENABLED_IRQS,
				adapter->hw_addr + REG_TIMB_IER);
		ks8842_write16(adapter, 18, ENABLED_IRQS, REG_IER);
	}
	/* enable the switch */
	ks8842_write16(adapter, 32, 0x1, REG_SW_ID_AND_ENABLE);
}

static void ks8842_read_mac_addr(struct ks8842_adapter *adapter, u8 *dest)
{
	int i;
	u16 mac;

	for (i = 0; i < ETH_ALEN; i++)
		dest[ETH_ALEN - i - 1] = ks8842_read8(adapter, 2, REG_MARL + i);

	if (adapter->conf_flags & MICREL_KS884X) {
		/*
		the sequence of saving mac addr between MAC and Switch is
		different.
		*/

		mac = ks8842_read16(adapter, 2, REG_MARL);
		ks8842_write16(adapter, 39, mac, REG_MACAR3);
		mac = ks8842_read16(adapter, 2, REG_MARM);
		ks8842_write16(adapter, 39, mac, REG_MACAR2);
		mac = ks8842_read16(adapter, 2, REG_MARH);
		ks8842_write16(adapter, 39, mac, REG_MACAR1);
	} else {

		/* make sure the switch port uses the same MAC as the QMU */
		mac = ks8842_read16(adapter, 2, REG_MARL);
		ks8842_write16(adapter, 39, mac, REG_MACAR1);
		mac = ks8842_read16(adapter, 2, REG_MARM);
		ks8842_write16(adapter, 39, mac, REG_MACAR2);
		mac = ks8842_read16(adapter, 2, REG_MARH);
		ks8842_write16(adapter, 39, mac, REG_MACAR3);
	}
}

static void ks8842_write_mac_addr(struct ks8842_adapter *adapter, u8 *mac)
{
	unsigned long flags;
	unsigned i;

	spin_lock_irqsave(&adapter->lock, flags);
	for (i = 0; i < ETH_ALEN; i++) {
		ks8842_write8(adapter, 2, mac[ETH_ALEN - i - 1], REG_MARL + i);
		if (!(adapter->conf_flags & MICREL_KS884X))
			ks8842_write8(adapter, 39, mac[ETH_ALEN - i - 1],
				REG_MACAR1 + i);
	}

	if (adapter->conf_flags & MICREL_KS884X) {
		/*
		the sequence of saving mac addr between MAC and Switch is
		different.
		*/

		u16 mac;

		mac = ks8842_read16(adapter, 2, REG_MARL);
		ks8842_write16(adapter, 39, mac, REG_MACAR3);
		mac = ks8842_read16(adapter, 2, REG_MARM);
		ks8842_write16(adapter, 39, mac, REG_MACAR2);
		mac = ks8842_read16(adapter, 2, REG_MARH);
		ks8842_write16(adapter, 39, mac, REG_MACAR1);
	}
	spin_unlock_irqrestore(&adapter->lock, flags);
}

static inline u16 ks8842_tx_fifo_space(struct ks8842_adapter *adapter)
{
	return ks8842_read16(adapter, 16, REG_TXMIR) & 0x1fff;
}

static int ks8842_tx_frame_dma(struct sk_buff *skb, struct net_device *netdev)
{
	struct ks8842_adapter *adapter = netdev_priv(netdev);
	struct ks8842_tx_dma_ctl *ctl = &adapter->dma_tx;
	u8 *buf = ctl->buf;

	if (ctl->adesc) {
		netdev_dbg(netdev, "%s: TX ongoing\n", __func__);
		/* transfer ongoing */
		return NETDEV_TX_BUSY;
	}

	sg_dma_len(&ctl->sg) = skb->len + sizeof(u32);

	/* copy data to the TX buffer */
	/* the control word, enable IRQ, port 1 and the length */
	*buf++ = 0x00;
	*buf++ = 0x01; /* Port 1 */
	*buf++ = skb->len & 0xff;
	*buf++ = (skb->len >> 8) & 0xff;
	skb_copy_from_linear_data(skb, buf, skb->len);

	dma_sync_single_range_for_device(adapter->dev,
		sg_dma_address(&ctl->sg), 0, sg_dma_len(&ctl->sg),
		DMA_TO_DEVICE);

	/* make sure the length is a multiple of 4 */
	if (sg_dma_len(&ctl->sg) % 4)
		sg_dma_len(&ctl->sg) += 4 - sg_dma_len(&ctl->sg) % 4;

	ctl->adesc = dmaengine_prep_slave_sg(ctl->chan,
		&ctl->sg, 1, DMA_MEM_TO_DEV,
		DMA_PREP_INTERRUPT | DMA_COMPL_SKIP_SRC_UNMAP);
	if (!ctl->adesc)
		return NETDEV_TX_BUSY;

	ctl->adesc->callback_param = netdev;
	ctl->adesc->callback = ks8842_dma_tx_cb;
	ctl->adesc->tx_submit(ctl->adesc);

	netdev->stats.tx_bytes += skb->len;

	dev_kfree_skb(skb);

	return NETDEV_TX_OK;
}

static int ks8842_tx_frame(struct sk_buff *skb, struct net_device *netdev)
{
	struct ks8842_adapter *adapter = netdev_priv(netdev);
	int len = skb->len;

	netdev_dbg(netdev, "%s: len %u head %p data %p tail %p end %p\n",
		__func__, skb->len, skb->head, skb->data,
		skb_tail_pointer(skb), skb_end_pointer(skb));

	/* check FIFO buffer space, we need space for CRC and command bits */
	if (ks8842_tx_fifo_space(adapter) < len + 8)
		return NETDEV_TX_BUSY;

	if (adapter->conf_flags & KS884X_16BIT) {
		u16 *ptr16 = (u16 *)skb->data;
		ks8842_write16(adapter, 17, 0x8000 | 0x100, REG_QMU_DATA_LO);
		ks8842_write16(adapter, 17, (u16)len, REG_QMU_DATA_HI);
		netdev->stats.tx_bytes += len;

		/* copy buffer */
		while (len > 0) {
			iowrite16(*ptr16++, adapter->hw_addr + REG_QMU_DATA_LO);
			iowrite16(*ptr16++, adapter->hw_addr + REG_QMU_DATA_HI);
			len -= sizeof(u32);
		}
	} else {

		u32 *ptr = (u32 *)skb->data;
		u32 ctrl;
		/* the control word, enable IRQ, port 1 and the length */
		ctrl = 0x8000 | 0x100 | (len << 16);
		ks8842_write32(adapter, 17, ctrl, REG_QMU_DATA_LO);

		netdev->stats.tx_bytes += len;

		/* copy buffer */
		while (len > 0) {
			iowrite32(*ptr, adapter->hw_addr + REG_QMU_DATA_LO);
			len -= sizeof(u32);
			ptr++;
		}
	}

	/* enqueue packet */
	ks8842_write16(adapter, 17, 1, REG_TXQCR);

	dev_kfree_skb(skb);

	return NETDEV_TX_OK;
}

static void ks8842_update_rx_err_counters(struct net_device *netdev, u32 status)
{
	netdev_dbg(netdev, "RX error, status: %x\n", status);

	netdev->stats.rx_errors++;
	if (status & RXSR_TOO_LONG)
		netdev->stats.rx_length_errors++;
	if (status & RXSR_CRC_ERROR)
		netdev->stats.rx_crc_errors++;
	if (status & RXSR_RUNT)
		netdev->stats.rx_frame_errors++;
}

static void ks8842_update_rx_counters(struct net_device *netdev, u32 status,
	int len)
{
	netdev_dbg(netdev, "RX packet, len: %d\n", len);

	netdev->stats.rx_packets++;
	netdev->stats.rx_bytes += len;
	if (status & RXSR_MULTICAST)
		netdev->stats.multicast++;
}

static int __ks8842_start_new_rx_dma(struct net_device *netdev)
{
	struct ks8842_adapter *adapter = netdev_priv(netdev);
	struct ks8842_rx_dma_ctl *ctl = &adapter->dma_rx;
	struct scatterlist *sg = &ctl->sg;
	int err;

	ctl->skb = netdev_alloc_skb(netdev, DMA_BUFFER_SIZE);
	if (ctl->skb) {
		sg_init_table(sg, 1);
		sg_dma_address(sg) = dma_map_single(adapter->dev,
			ctl->skb->data, DMA_BUFFER_SIZE, DMA_FROM_DEVICE);
		err = dma_mapping_error(adapter->dev, sg_dma_address(sg));
		if (unlikely(err)) {
			sg_dma_address(sg) = 0;
			goto out;
		}

		sg_dma_len(sg) = DMA_BUFFER_SIZE;

		ctl->adesc = dmaengine_prep_slave_sg(ctl->chan,
			sg, 1, DMA_DEV_TO_MEM,
			DMA_PREP_INTERRUPT | DMA_COMPL_SKIP_SRC_UNMAP);

		if (!ctl->adesc)
			goto out;

		ctl->adesc->callback_param = netdev;
		ctl->adesc->callback = ks8842_dma_rx_cb;
		ctl->adesc->tx_submit(ctl->adesc);
	} else {
		err = -ENOMEM;
		sg_dma_address(sg) = 0;
		goto out;
	}

	return err;
out:
	if (sg_dma_address(sg))
		dma_unmap_single(adapter->dev, sg_dma_address(sg),
			DMA_BUFFER_SIZE, DMA_FROM_DEVICE);
	sg_dma_address(sg) = 0;
	if (ctl->skb)
		dev_kfree_skb(ctl->skb);

	ctl->skb = NULL;

	printk(KERN_ERR DRV_NAME": Failed to start RX DMA: %d\n", err);
	return err;
}

static void ks8842_rx_frame_dma_tasklet(unsigned long arg)
{
	struct net_device *netdev = (struct net_device *)arg;
	struct ks8842_adapter *adapter = netdev_priv(netdev);
	struct ks8842_rx_dma_ctl *ctl = &adapter->dma_rx;
	struct sk_buff *skb = ctl->skb;
	dma_addr_t addr = sg_dma_address(&ctl->sg);
	u32 status;

	ctl->adesc = NULL;

	/* kick next transfer going */
	__ks8842_start_new_rx_dma(netdev);

	/* now handle the data we got */
	dma_unmap_single(adapter->dev, addr, DMA_BUFFER_SIZE, DMA_FROM_DEVICE);

	status = *((u32 *)skb->data);

	netdev_dbg(netdev, "%s - rx_data: status: %x\n",
		__func__, status & 0xffff);

	/* check the status */
	if ((status & RXSR_VALID) && !(status & RXSR_ERROR)) {
		int len = (status >> 16) & 0x7ff;

		ks8842_update_rx_counters(netdev, status, len);

		/* reserve 4 bytes which is the status word */
		skb_reserve(skb, 4);
		skb_put(skb, len);

		skb->protocol = eth_type_trans(skb, netdev);
		netif_rx(skb);
	} else {
		ks8842_update_rx_err_counters(netdev, status);
		dev_kfree_skb(skb);
	}
}

static void ks8842_rx_frame(struct net_device *netdev,
	struct ks8842_adapter *adapter)
{
	u32 status;
	int len;

	if (adapter->conf_flags & KS884X_16BIT) {
		status = ks8842_read16(adapter, 17, REG_QMU_DATA_LO);
		len = ks8842_read16(adapter, 17, REG_QMU_DATA_HI);
		netdev_dbg(netdev, "%s - rx_data: status: %x\n",
			   __func__, status);
	} else {
		status = ks8842_read32(adapter, 17, REG_QMU_DATA_LO);
		len = (status >> 16) & 0x7ff;
		status &= 0xffff;
		netdev_dbg(netdev, "%s - rx_data: status: %x\n",
			   __func__, status);
	}

	/* check the status */
	if ((status & RXSR_VALID) && !(status & RXSR_ERROR)) {
		struct sk_buff *skb = netdev_alloc_skb_ip_align(netdev, len + 3);

		if (skb) {

			ks8842_update_rx_counters(netdev, status, len);

			if (adapter->conf_flags & KS884X_16BIT) {
				u16 *data16 = (u16 *)skb_put(skb, len);
				ks8842_select_bank(adapter, 17);
				while (len > 0) {
					*data16++ = ioread16(adapter->hw_addr +
						REG_QMU_DATA_LO);
					*data16++ = ioread16(adapter->hw_addr +
						REG_QMU_DATA_HI);
					len -= sizeof(u32);
				}
			} else {
				u32 *data = (u32 *)skb_put(skb, len);

				ks8842_select_bank(adapter, 17);
				while (len > 0) {
					*data++ = ioread32(adapter->hw_addr +
						REG_QMU_DATA_LO);
					len -= sizeof(u32);
				}
			}
			skb->protocol = eth_type_trans(skb, netdev);
			netif_rx(skb);
		} else
			netdev->stats.rx_dropped++;
	} else
		ks8842_update_rx_err_counters(netdev, status);

	/* set high watermark to 3K */
	ks8842_clear_bits(adapter, 0, 1 << 12, REG_QRFCR);

	/* release the frame */
	ks8842_write16(adapter, 17, 0x01, REG_RXQCR);

	/* set high watermark to 2K */
	ks8842_enable_bits(adapter, 0, 1 << 12, REG_QRFCR);
}

void ks8842_handle_rx(struct net_device *netdev, struct ks8842_adapter *adapter)
{
	u16 rx_data = ks8842_read16(adapter, 16, REG_RXMIR) & 0x1fff;
	netdev_dbg(netdev, "%s Entry - rx_data: %d\n", __func__, rx_data);
	while (rx_data) {
		ks8842_rx_frame(netdev, adapter);
		rx_data = ks8842_read16(adapter, 16, REG_RXMIR) & 0x1fff;
	}
}

void ks8842_handle_tx(struct net_device *netdev, struct ks8842_adapter *adapter)
{
	u16 sr = ks8842_read16(adapter, 16, REG_TXSR);
	netdev_dbg(netdev, "%s - entry, sr: %x\n", __func__, sr);
	netdev->stats.tx_packets++;
	if (netif_queue_stopped(netdev))
		netif_wake_queue(netdev);
}

void ks8842_handle_rx_overrun(struct net_device *netdev,
	struct ks8842_adapter *adapter)
{
	netdev_dbg(netdev, "%s: entry\n", __func__);
	netdev->stats.rx_errors++;
	netdev->stats.rx_fifo_errors++;
}

void ks8842_tasklet(unsigned long arg)
{
	struct net_device *netdev = (struct net_device *)arg;
	struct ks8842_adapter *adapter = netdev_priv(netdev);
	u16 isr;
	unsigned long flags;
	u16 entry_bank;

	/* read current bank to be able to set it back */
	spin_lock_irqsave(&adapter->lock, flags);
	entry_bank = ioread16(adapter->hw_addr + REG_SELECT_BANK);
	spin_unlock_irqrestore(&adapter->lock, flags);

	isr = ks8842_read16(adapter, 18, REG_ISR);
	netdev_dbg(netdev, "%s - ISR: 0x%x\n", __func__, isr);

	/* when running in DMA mode, do not ack RX interrupts, it is handled
	   internally by timberdale, otherwise it's DMA FIFO:s would stop
	*/
	if (KS8842_USE_DMA(adapter))
		isr &= ~IRQ_RX;

	/* Ack */
	ks8842_write16(adapter, 18, isr, REG_ISR);

	if (!(adapter->conf_flags & MICREL_KS884X))
		/* Ack in the timberdale IP as well */
		iowrite32(0x1, adapter->hw_addr + REG_TIMB_IAR);

	if (!netif_running(netdev))
		return;

	if (isr & IRQ_LINK_CHANGE)
		ks8842_update_link_status(netdev, adapter);

	/* should not get IRQ_RX when running DMA mode */
	if (isr & (IRQ_RX | IRQ_RX_ERROR) && !KS8842_USE_DMA(adapter))
		ks8842_handle_rx(netdev, adapter);

	/* should only happen when in PIO mode */
	if (isr & IRQ_TX)
		ks8842_handle_tx(netdev, adapter);

	if (isr & IRQ_RX_OVERRUN)
		ks8842_handle_rx_overrun(netdev, adapter);

	if (isr & IRQ_TX_STOPPED) {
		ks8842_disable_tx(adapter);
		ks8842_enable_tx(adapter);
	}

	if (isr & IRQ_RX_STOPPED) {
		ks8842_disable_rx(adapter);
		ks8842_enable_rx(adapter);
	}

	/* re-enable interrupts, put back the bank selection register */
	spin_lock_irqsave(&adapter->lock, flags);
	if (KS8842_USE_DMA(adapter))
		ks8842_write16(adapter, 18, ENABLED_IRQS_DMA, REG_IER);
	else
		ks8842_write16(adapter, 18, ENABLED_IRQS, REG_IER);
	iowrite16(entry_bank, adapter->hw_addr + REG_SELECT_BANK);

	/* Make sure timberdale continues DMA operations, they are stopped while
	   we are handling the ks8842 because we might change bank */
	if (KS8842_USE_DMA(adapter))
		ks8842_resume_dma(adapter);

	spin_unlock_irqrestore(&adapter->lock, flags);
}

static irqreturn_t ks8842_irq(int irq, void *devid)
{
	struct net_device *netdev = devid;
	struct ks8842_adapter *adapter = netdev_priv(netdev);
	u16 isr;
	u16 entry_bank = ioread16(adapter->hw_addr + REG_SELECT_BANK);
	irqreturn_t ret = IRQ_NONE;

	isr = ks8842_read16(adapter, 18, REG_ISR);
	netdev_dbg(netdev, "%s - ISR: 0x%x\n", __func__, isr);

	if (isr) {
		if (KS8842_USE_DMA(adapter))
			/* disable all but RX IRQ, since the FPGA relies on it*/
			ks8842_write16(adapter, 18, IRQ_RX, REG_IER);
		else
			/* disable IRQ */
			ks8842_write16(adapter, 18, 0x00, REG_IER);

		/* schedule tasklet */
		tasklet_schedule(&adapter->tasklet);

		ret = IRQ_HANDLED;
	}

	iowrite16(entry_bank, adapter->hw_addr + REG_SELECT_BANK);

	/* After an interrupt, tell timberdale to continue DMA operations.
	   DMA is disabled while we are handling the ks8842 because we might
	   change bank */
	ks8842_resume_dma(adapter);

	return ret;
}

static void ks8842_dma_rx_cb(void *data)
{
	struct net_device	*netdev = data;
	struct ks8842_adapter	*adapter = netdev_priv(netdev);

	netdev_dbg(netdev, "RX DMA finished\n");
	/* schedule tasklet */
	if (adapter->dma_rx.adesc)
		tasklet_schedule(&adapter->dma_rx.tasklet);
}

static void ks8842_dma_tx_cb(void *data)
{
	struct net_device		*netdev = data;
	struct ks8842_adapter		*adapter = netdev_priv(netdev);
	struct ks8842_tx_dma_ctl	*ctl = &adapter->dma_tx;

	netdev_dbg(netdev, "TX DMA finished\n");

	if (!ctl->adesc)
		return;

	netdev->stats.tx_packets++;
	ctl->adesc = NULL;

	if (netif_queue_stopped(netdev))
		netif_wake_queue(netdev);
}

static void ks8842_stop_dma(struct ks8842_adapter *adapter)
{
	struct ks8842_tx_dma_ctl *tx_ctl = &adapter->dma_tx;
	struct ks8842_rx_dma_ctl *rx_ctl = &adapter->dma_rx;

	tx_ctl->adesc = NULL;
	if (tx_ctl->chan)
		tx_ctl->chan->device->device_control(tx_ctl->chan,
			DMA_TERMINATE_ALL, 0);

	rx_ctl->adesc = NULL;
	if (rx_ctl->chan)
		rx_ctl->chan->device->device_control(rx_ctl->chan,
			DMA_TERMINATE_ALL, 0);

	if (sg_dma_address(&rx_ctl->sg))
		dma_unmap_single(adapter->dev, sg_dma_address(&rx_ctl->sg),
			DMA_BUFFER_SIZE, DMA_FROM_DEVICE);
	sg_dma_address(&rx_ctl->sg) = 0;

	dev_kfree_skb(rx_ctl->skb);
	rx_ctl->skb = NULL;
}

static void ks8842_dealloc_dma_bufs(struct ks8842_adapter *adapter)
{
	struct ks8842_tx_dma_ctl *tx_ctl = &adapter->dma_tx;
	struct ks8842_rx_dma_ctl *rx_ctl = &adapter->dma_rx;

	ks8842_stop_dma(adapter);

	if (tx_ctl->chan)
		dma_release_channel(tx_ctl->chan);
	tx_ctl->chan = NULL;

	if (rx_ctl->chan)
		dma_release_channel(rx_ctl->chan);
	rx_ctl->chan = NULL;

	tasklet_kill(&rx_ctl->tasklet);

	if (sg_dma_address(&tx_ctl->sg))
		dma_unmap_single(adapter->dev, sg_dma_address(&tx_ctl->sg),
			DMA_BUFFER_SIZE, DMA_TO_DEVICE);
	sg_dma_address(&tx_ctl->sg) = 0;

	kfree(tx_ctl->buf);
	tx_ctl->buf = NULL;
}

static bool ks8842_dma_filter_fn(struct dma_chan *chan, void *filter_param)
{
	return chan->chan_id == (long)filter_param;
}

static int ks8842_alloc_dma_bufs(struct net_device *netdev)
{
	struct ks8842_adapter *adapter = netdev_priv(netdev);
	struct ks8842_tx_dma_ctl *tx_ctl = &adapter->dma_tx;
	struct ks8842_rx_dma_ctl *rx_ctl = &adapter->dma_rx;
	int err;

	dma_cap_mask_t mask;

	dma_cap_zero(mask);
	dma_cap_set(DMA_SLAVE, mask);
	dma_cap_set(DMA_PRIVATE, mask);

	sg_init_table(&tx_ctl->sg, 1);

	tx_ctl->chan = dma_request_channel(mask, ks8842_dma_filter_fn,
					   (void *)(long)tx_ctl->channel);
	if (!tx_ctl->chan) {
		err = -ENODEV;
		goto err;
	}

	/* allocate DMA buffer */
	tx_ctl->buf = kmalloc(DMA_BUFFER_SIZE, GFP_KERNEL);
	if (!tx_ctl->buf) {
		err = -ENOMEM;
		goto err;
	}

	sg_dma_address(&tx_ctl->sg) = dma_map_single(adapter->dev,
		tx_ctl->buf, DMA_BUFFER_SIZE, DMA_TO_DEVICE);
	err = dma_mapping_error(adapter->dev,
		sg_dma_address(&tx_ctl->sg));
	if (err) {
		sg_dma_address(&tx_ctl->sg) = 0;
		goto err;
	}

	rx_ctl->chan = dma_request_channel(mask, ks8842_dma_filter_fn,
					   (void *)(long)rx_ctl->channel);
	if (!rx_ctl->chan) {
		err = -ENODEV;
		goto err;
	}

	tasklet_init(&rx_ctl->tasklet, ks8842_rx_frame_dma_tasklet,
		(unsigned long)netdev);

	return 0;
err:
	ks8842_dealloc_dma_bufs(adapter);
	return err;
}

/* Netdevice operations */

static int ks8842_open(struct net_device *netdev)
{
	struct ks8842_adapter *adapter = netdev_priv(netdev);
	int err;

	netdev_dbg(netdev, "%s - entry\n", __func__);

	if (KS8842_USE_DMA(adapter)) {
		err = ks8842_alloc_dma_bufs(netdev);

		if (!err) {
			/* start RX dma */
			err = __ks8842_start_new_rx_dma(netdev);
			if (err)
				ks8842_dealloc_dma_bufs(adapter);
		}

		if (err) {
			printk(KERN_WARNING DRV_NAME
				": Failed to initiate DMA, running PIO\n");
			ks8842_dealloc_dma_bufs(adapter);
			adapter->dma_rx.channel = -1;
			adapter->dma_tx.channel = -1;
		}
	}

	/* reset the HW */
	ks8842_reset_hw(adapter);

	ks8842_write_mac_addr(adapter, netdev->dev_addr);

	ks8842_update_link_status(netdev, adapter);

	err = request_irq(adapter->irq, ks8842_irq, IRQF_SHARED, DRV_NAME,
		netdev);
	if (err) {
		pr_err("Failed to request IRQ: %d: %d\n", adapter->irq, err);
		return err;
	}

	return 0;
}

static int ks8842_close(struct net_device *netdev)
{
	struct ks8842_adapter *adapter = netdev_priv(netdev);

	netdev_dbg(netdev, "%s - entry\n", __func__);

	cancel_work_sync(&adapter->timeout_work);

	if (KS8842_USE_DMA(adapter))
		ks8842_dealloc_dma_bufs(adapter);

	/* free the irq */
	free_irq(adapter->irq, netdev);

	/* disable the switch */
	ks8842_write16(adapter, 32, 0x0, REG_SW_ID_AND_ENABLE);

	return 0;
}

static netdev_tx_t ks8842_xmit_frame(struct sk_buff *skb,
				     struct net_device *netdev)
{
	int ret;
	struct ks8842_adapter *adapter = netdev_priv(netdev);

	netdev_dbg(netdev, "%s: entry\n", __func__);

	if (KS8842_USE_DMA(adapter)) {
		unsigned long flags;
		ret = ks8842_tx_frame_dma(skb, netdev);
		/* for now only allow one transfer at the time */
		spin_lock_irqsave(&adapter->lock, flags);
		if (adapter->dma_tx.adesc)
			netif_stop_queue(netdev);
		spin_unlock_irqrestore(&adapter->lock, flags);
		return ret;
	}

	ret = ks8842_tx_frame(skb, netdev);

	if (ks8842_tx_fifo_space(adapter) <  netdev->mtu + 8)
		netif_stop_queue(netdev);

	return ret;
}

static int ks8842_set_mac(struct net_device *netdev, void *p)
{
	struct ks8842_adapter *adapter = netdev_priv(netdev);
	struct sockaddr *addr = p;
	char *mac = (u8 *)addr->sa_data;

	netdev_dbg(netdev, "%s: entry\n", __func__);

	if (!is_valid_ether_addr(addr->sa_data))
		return -EADDRNOTAVAIL;

	netdev->addr_assign_type &= ~NET_ADDR_RANDOM;
	memcpy(netdev->dev_addr, mac, netdev->addr_len);

	ks8842_write_mac_addr(adapter, mac);
	return 0;
}

static void ks8842_tx_timeout_work(struct work_struct *work)
{
	struct ks8842_adapter *adapter =
		container_of(work, struct ks8842_adapter, timeout_work);
	struct net_device *netdev = adapter->netdev;
	unsigned long flags;

	netdev_dbg(netdev, "%s: entry\n", __func__);

	spin_lock_irqsave(&adapter->lock, flags);

	if (KS8842_USE_DMA(adapter))
		ks8842_stop_dma(adapter);

	/* disable interrupts */
	ks8842_write16(adapter, 18, 0, REG_IER);
	ks8842_write16(adapter, 18, 0xFFFF, REG_ISR);

	netif_stop_queue(netdev);

	spin_unlock_irqrestore(&adapter->lock, flags);

	ks8842_reset_hw(adapter);

	ks8842_write_mac_addr(adapter, netdev->dev_addr);

	ks8842_update_link_status(netdev, adapter);

	if (KS8842_USE_DMA(adapter))
		__ks8842_start_new_rx_dma(netdev);
}

static void ks8842_tx_timeout(struct net_device *netdev)
{
	struct ks8842_adapter *adapter = netdev_priv(netdev);

	netdev_dbg(netdev, "%s: entry\n", __func__);

	schedule_work(&adapter->timeout_work);
}

static const struct net_device_ops ks8842_netdev_ops = {
	.ndo_open		= ks8842_open,
	.ndo_stop		= ks8842_close,
	.ndo_start_xmit		= ks8842_xmit_frame,
	.ndo_set_mac_address	= ks8842_set_mac,
	.ndo_tx_timeout 	= ks8842_tx_timeout,
	.ndo_validate_addr	= eth_validate_addr
};

static const struct ethtool_ops ks8842_ethtool_ops = {
	.get_link		= ethtool_op_get_link,
};

static int __devinit ks8842_probe(struct platform_device *pdev)
{
	int err = -ENOMEM;
	struct resource *iomem;
	struct net_device *netdev;
	struct ks8842_adapter *adapter;
	struct ks8842_platform_data *pdata = pdev->dev.platform_data;
	u16 id;
	unsigned i;

	iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!request_mem_region(iomem->start, resource_size(iomem), DRV_NAME))
		goto err_mem_region;

	netdev = alloc_etherdev(sizeof(struct ks8842_adapter));
	if (!netdev)
		goto err_alloc_etherdev;

	SET_NETDEV_DEV(netdev, &pdev->dev);

	adapter = netdev_priv(netdev);
	adapter->netdev = netdev;
	INIT_WORK(&adapter->timeout_work, ks8842_tx_timeout_work);
	adapter->hw_addr = ioremap(iomem->start, resource_size(iomem));
	adapter->conf_flags = iomem->flags;

	if (!adapter->hw_addr)
		goto err_ioremap;

	adapter->irq = platform_get_irq(pdev, 0);
	if (adapter->irq < 0) {
		err = adapter->irq;
		goto err_get_irq;
	}

	adapter->dev = (pdev->dev.parent) ? pdev->dev.parent : &pdev->dev;

	/* DMA is only supported when accessed via timberdale */
	if (!(adapter->conf_flags & MICREL_KS884X) && pdata &&
		(pdata->tx_dma_channel != -1) &&
		(pdata->rx_dma_channel != -1)) {
		adapter->dma_rx.channel = pdata->rx_dma_channel;
		adapter->dma_tx.channel = pdata->tx_dma_channel;
	} else {
		adapter->dma_rx.channel = -1;
		adapter->dma_tx.channel = -1;
	}

	tasklet_init(&adapter->tasklet, ks8842_tasklet, (unsigned long)netdev);
	spin_lock_init(&adapter->lock);

	netdev->netdev_ops = &ks8842_netdev_ops;
	netdev->ethtool_ops = &ks8842_ethtool_ops;

	/* Check if a mac address was given */
	i = netdev->addr_len;
	if (pdata) {
		for (i = 0; i < netdev->addr_len; i++)
			if (pdata->macaddr[i] != 0)
				break;

		if (i < netdev->addr_len)
			/* an address was passed, use it */
			memcpy(netdev->dev_addr, pdata->macaddr,
				netdev->addr_len);
	}

	if (i == netdev->addr_len) {
		ks8842_read_mac_addr(adapter, netdev->dev_addr);

		if (!is_valid_ether_addr(netdev->dev_addr))
			eth_hw_addr_random(netdev);
	}

	id = ks8842_read16(adapter, 32, REG_SW_ID_AND_ENABLE);

	strcpy(netdev->name, "eth%d");
	err = register_netdev(netdev);
	if (err)
		goto err_register;

	platform_set_drvdata(pdev, netdev);

	pr_info("Found chip, family: 0x%x, id: 0x%x, rev: 0x%x\n",
		(id >> 8) & 0xff, (id >> 4) & 0xf, (id >> 1) & 0x7);

	return 0;

err_register:
err_get_irq:
	iounmap(adapter->hw_addr);
err_ioremap:
	free_netdev(netdev);
err_alloc_etherdev:
	release_mem_region(iomem->start, resource_size(iomem));
err_mem_region:
	return err;
}

static int __devexit ks8842_remove(struct platform_device *pdev)
{
	struct net_device *netdev = platform_get_drvdata(pdev);
	struct ks8842_adapter *adapter = netdev_priv(netdev);
	struct resource *iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);

	unregister_netdev(netdev);
	tasklet_kill(&adapter->tasklet);
	iounmap(adapter->hw_addr);
	free_netdev(netdev);
	release_mem_region(iomem->start, resource_size(iomem));
	platform_set_drvdata(pdev, NULL);
	return 0;
}


static struct platform_driver ks8842_platform_driver = {
	.driver = {
		.name	= DRV_NAME,
		.owner	= THIS_MODULE,
	},
	.probe		= ks8842_probe,
	.remove		= __devexit_p(ks8842_remove),
};

module_platform_driver(ks8842_platform_driver);

MODULE_DESCRIPTION("Timberdale KS8842 ethernet driver");
MODULE_AUTHOR("Mocean Laboratories <info@mocean-labs.com>");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:ks8842");