summaryrefslogtreecommitdiff
path: root/drivers/net/wireless/libertas/if_usb.c
blob: ae6f72a6cdf396d5946e5ff1de1863c18a6d0380 (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
/**
  * This file contains functions used in USB interface module.
  */
#include <linux/delay.h>
#include <linux/firmware.h>
#include <linux/netdevice.h>
#include <linux/usb.h>

#include "host.h"
#include "sbi.h"
#include "decl.h"
#include "defs.h"
#include "dev.h"
#include "if_usb.h"

#define MESSAGE_HEADER_LEN	4

static const char usbdriver_name[] = "usb8xxx";

static struct usb_device_id if_usb_table[] = {
	/* Enter the device signature inside */
	{
		USB_DEVICE(USB8388_VID_1, USB8388_PID_1),
	},
	{
		USB_DEVICE(USB8388_VID_2, USB8388_PID_2),
	},
	{}	/* Terminating entry */
};

MODULE_DEVICE_TABLE(usb, if_usb_table);

static void if_usb_receive(struct urb *urb);
static void if_usb_receive_fwload(struct urb *urb);

/**
 *  @brief  call back function to handle the status of the URB
 *  @param urb 		pointer to urb structure
 *  @return 	   	N/A
 */
static void if_usb_write_bulk_callback(struct urb *urb)
{
	wlan_private *priv = (wlan_private *) (urb->context);
	wlan_adapter *adapter = priv->adapter;
	struct net_device *dev = priv->wlan_dev.netdev;

	/* handle the transmission complete validations */

	if (urb->status != 0) {
		/* print the failure status number for debug */
		lbs_pr_info("URB in failure status\n");
	} else {
		lbs_dev_dbg(2, &urb->dev->dev, "URB status is successfull\n");
		lbs_dev_dbg(2, &urb->dev->dev, "Actual length transmitted %d\n",
		       urb->actual_length);
		priv->wlan_dev.dnld_sent = DNLD_RES_RECEIVED;
		/* Wake main thread if commands are pending */
		if (!adapter->cur_cmd)
			wake_up_interruptible(&priv->mainthread.waitq);
		if ((adapter->connect_status == libertas_connected))
			netif_wake_queue(dev);
	}

	return;
}

/**
 *  @brief  free tx/rx urb, skb and rx buffer
 *  @param cardp	pointer usb_card_rec
 *  @return 	   	N/A
 */
void if_usb_free(struct usb_card_rec *cardp)
{
	ENTER();

	/* Unlink tx & rx urb */
	usb_kill_urb(cardp->tx_urb);
	usb_kill_urb(cardp->rx_urb);

	usb_free_urb(cardp->tx_urb);
	cardp->tx_urb = NULL;

	usb_free_urb(cardp->rx_urb);
	cardp->rx_urb = NULL;

	kfree(cardp->bulk_out_buffer);
	cardp->bulk_out_buffer = NULL;

	LEAVE();
	return;
}

/**
 *  @brief sets the configuration values
 *  @param ifnum	interface number
 *  @param id		pointer to usb_device_id
 *  @return 	   	0 on success, error code on failure
 */
static int if_usb_probe(struct usb_interface *intf,
			const struct usb_device_id *id)
{
	struct usb_device *udev;
	struct usb_host_interface *iface_desc;
	struct usb_endpoint_descriptor *endpoint;
	wlan_private *pwlanpriv;
	struct usb_card_rec *usb_cardp;
	int i;

	udev = interface_to_usbdev(intf);

	usb_cardp = kzalloc(sizeof(struct usb_card_rec), GFP_KERNEL);
	if (!usb_cardp) {
		lbs_pr_err("Out of memory allocating private data.\n");
		goto error;
	}

	usb_cardp->udev = udev;
	iface_desc = intf->cur_altsetting;

	lbs_dev_dbg(1, &udev->dev, "bcdUSB = 0x%X bDeviceClass = 0x%X"
	       " bDeviceSubClass = 0x%X, bDeviceProtocol = 0x%X\n",
	       udev->descriptor.bcdUSB,
	       udev->descriptor.bDeviceClass,
	       udev->descriptor.bDeviceSubClass,
	       udev->descriptor.bDeviceProtocol);

	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
		endpoint = &iface_desc->endpoint[i].desc;
		if ((endpoint->bEndpointAddress & USB_ENDPOINT_DIR_MASK)
		    && ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) ==
			USB_ENDPOINT_XFER_BULK)) {
			/* we found a bulk in endpoint */
			lbs_dev_dbg(1, &udev->dev, "Bulk in size is %d\n",
			       endpoint->wMaxPacketSize);
			if (!
			    (usb_cardp->rx_urb =
			     usb_alloc_urb(0, GFP_KERNEL))) {
				lbs_dev_dbg(1, &udev->dev,
				       "Rx URB allocation failed\n");
				goto dealloc;
			}
			usb_cardp->rx_urb_recall = 0;

			usb_cardp->bulk_in_size =
			    endpoint->wMaxPacketSize;
			usb_cardp->bulk_in_endpointAddr =
			    (endpoint->
			     bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
			lbs_dev_dbg(1, &udev->dev, "in_endpoint = %d\n",
			       endpoint->bEndpointAddress);
		}

		if (((endpoint->
		      bEndpointAddress & USB_ENDPOINT_DIR_MASK) ==
		     USB_DIR_OUT)
		    && ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) ==
			USB_ENDPOINT_XFER_BULK)) {
			/* We found bulk out endpoint */
			if (!
			    (usb_cardp->tx_urb =
			     usb_alloc_urb(0, GFP_KERNEL))) {
				lbs_dev_dbg(1,&udev->dev,
				       "Tx URB allocation failed\n");
				goto dealloc;
			}

			usb_cardp->bulk_out_size =
			    endpoint->wMaxPacketSize;
			lbs_dev_dbg(1, &udev->dev,
				    "Bulk out size is %d\n",
				    endpoint->wMaxPacketSize);
			usb_cardp->bulk_out_endpointAddr =
			    endpoint->bEndpointAddress;
			lbs_dev_dbg(1, &udev->dev, "out_endpoint = %d\n",
				    endpoint->bEndpointAddress);
			usb_cardp->bulk_out_buffer =
			    kmalloc(MRVDRV_ETH_TX_PACKET_BUFFER_SIZE,
				    GFP_KERNEL);

			if (!usb_cardp->bulk_out_buffer) {
				lbs_dev_dbg(1, &udev->dev,
				       "Could not allocate buffer\n");
				goto dealloc;
			}
		}
	}


	/* At this point wlan_add_card() will be called.  Don't worry
	 * about keeping pwlanpriv around since it will be set on our
	 * usb device data in -> add() -> libertas_sbi_register_dev().
	 */
	if (!(pwlanpriv = wlan_add_card(usb_cardp)))
		goto dealloc;

	usb_get_dev(udev);
	usb_set_intfdata(intf, usb_cardp);

	/*
	 * return card structure, which can be got back in the
	 * diconnect function as the ptr
	 * argument.
	 */
	return 0;

dealloc:
	if_usb_free(usb_cardp);

error:
	return -ENOMEM;
}

/**
 *  @brief free resource and cleanup
 *  @param udev		pointer to usb_device
 *  @param ptr		pointer to usb_cardp
 *  @return 	   	N/A
 */
static void if_usb_disconnect(struct usb_interface *intf)
{
	struct usb_card_rec *cardp = usb_get_intfdata(intf);
	wlan_private *priv = (wlan_private *) cardp->priv;
	wlan_adapter *adapter = NULL;

	adapter = priv->adapter;

	/*
	 * Update Surprise removed to TRUE
	 */
	adapter->surpriseremoved = 1;

	/* card is removed and we can call wlan_remove_card */
	lbs_dev_dbg(1, &cardp->udev->dev, "call remove card\n");
	wlan_remove_card(cardp);

	/* Unlink and free urb */
	if_usb_free(cardp);

	usb_set_intfdata(intf, NULL);
	usb_put_dev(interface_to_usbdev(intf));

	return;
}

/**
 *  @brief  This function download FW
 *  @param priv		pointer to wlan_private
 *  @return 	   	0
 */
static int if_prog_firmware(wlan_private * priv)
{
	struct usb_card_rec *cardp = priv->wlan_dev.card;
	struct FWData *fwdata;
	struct fwheader *fwheader;
	u8 *firmware = priv->firmware->data;

	fwdata = kmalloc(sizeof(struct FWData), GFP_ATOMIC);

	if (!fwdata)
		return -1;

	fwheader = &fwdata->fwheader;

	if (!cardp->CRC_OK) {
		cardp->totalbytes = cardp->fwlastblksent;
		cardp->fwseqnum = cardp->lastseqnum - 1;
	}

	lbs_dev_dbg(2, &cardp->udev->dev, "totalbytes = %d\n",
		    cardp->totalbytes);

	memcpy(fwheader, &firmware[cardp->totalbytes],
	       sizeof(struct fwheader));

	cardp->fwlastblksent = cardp->totalbytes;
	cardp->totalbytes += sizeof(struct fwheader);

	lbs_dev_dbg(2, &cardp->udev->dev,"Copy Data\n");
	memcpy(fwdata->data, &firmware[cardp->totalbytes],
	       fwdata->fwheader.datalength);

	lbs_dev_dbg(2, &cardp->udev->dev,
		    "Data length = %d\n", fwdata->fwheader.datalength);

	cardp->fwseqnum = cardp->fwseqnum + 1;

	fwdata->seqnum = cardp->fwseqnum;
	cardp->lastseqnum = fwdata->seqnum;
	cardp->totalbytes += fwdata->fwheader.datalength;

	if (fwheader->dnldcmd == FW_HAS_DATA_TO_RECV) {
		lbs_dev_dbg(2, &cardp->udev->dev, "There is data to follow\n");
		lbs_dev_dbg(2, &cardp->udev->dev,
			    "seqnum = %d totalbytes = %d\n", cardp->fwseqnum,
			    cardp->totalbytes);
		memcpy(cardp->bulk_out_buffer, fwheader, FW_DATA_XMIT_SIZE);
		usb_tx_block(priv, cardp->bulk_out_buffer, FW_DATA_XMIT_SIZE);

	} else if (fwdata->fwheader.dnldcmd == FW_HAS_LAST_BLOCK) {
		lbs_dev_dbg(2, &cardp->udev->dev,
			    "Host has finished FW downloading\n");
		lbs_dev_dbg(2, &cardp->udev->dev,
			    "Donwloading FW JUMP BLOCK\n");
		memcpy(cardp->bulk_out_buffer, fwheader, FW_DATA_XMIT_SIZE);
		usb_tx_block(priv, cardp->bulk_out_buffer, FW_DATA_XMIT_SIZE);
		cardp->fwfinalblk = 1;
	}

	lbs_dev_dbg(2, &cardp->udev->dev,
		    "The firmware download is done size is %d\n",
		    cardp->totalbytes);

	kfree(fwdata);

	return 0;
}

static int libertas_do_reset(wlan_private *priv)
{
	int ret;
	struct usb_card_rec *cardp = priv->wlan_dev.card;

	ret = usb_reset_device(cardp->udev);
	if (!ret) {
		msleep(10);
		reset_device(priv);
		msleep(10);
	}
	return ret;
}

/**
 *  @brief This function transfer the data to the device.
 *  @param priv 	pointer to wlan_private
 *  @param payload	pointer to payload data
 *  @param nb		data length
 *  @return 	   	0 or -1
 */
int usb_tx_block(wlan_private * priv, u8 * payload, u16 nb)
{
	/* pointer to card structure */
	struct usb_card_rec *cardp = priv->wlan_dev.card;
	int ret = -1;

	/* check if device is removed */
	if (priv->adapter->surpriseremoved) {
		lbs_dev_dbg(1, &cardp->udev->dev, "Device removed\n");
		goto tx_ret;
	}

	usb_fill_bulk_urb(cardp->tx_urb, cardp->udev,
			  usb_sndbulkpipe(cardp->udev,
					  cardp->bulk_out_endpointAddr),
			  payload, nb, if_usb_write_bulk_callback, priv);

	cardp->tx_urb->transfer_flags |= URB_ZERO_PACKET;

	if ((ret = usb_submit_urb(cardp->tx_urb, GFP_ATOMIC))) {
		/*  transfer failed */
		lbs_dev_dbg(1, &cardp->udev->dev, "usb_submit_urb failed\n");
		ret = -1;
	} else {
		lbs_dev_dbg(2, &cardp->udev->dev, "usb_submit_urb success\n");
		ret = 0;
	}

tx_ret:
	return ret;
}

static int __if_usb_submit_rx_urb(wlan_private * priv,
				  void (*callbackfn)
				  (struct urb *urb))
{
	struct usb_card_rec *cardp = priv->wlan_dev.card;
	struct sk_buff *skb;
	struct read_cb_info *rinfo = &cardp->rinfo;
	int ret = -1;

	if (!(skb = dev_alloc_skb(MRVDRV_ETH_RX_PACKET_BUFFER_SIZE))) {
		lbs_pr_err("No free skb\n");
		goto rx_ret;
	}

	rinfo->skb = skb;

	/* Fill the receive configuration URB and initialise the Rx call back */
	usb_fill_bulk_urb(cardp->rx_urb, cardp->udev,
			  usb_rcvbulkpipe(cardp->udev,
					  cardp->bulk_in_endpointAddr),
			  (void *) (skb->tail + (size_t) IPFIELD_ALIGN_OFFSET),
			  MRVDRV_ETH_RX_PACKET_BUFFER_SIZE, callbackfn,
			  rinfo);

	cardp->rx_urb->transfer_flags |= URB_ZERO_PACKET;

	lbs_dev_dbg(2, &cardp->udev->dev, "Pointer for rx_urb %p\n", cardp->rx_urb);
	if ((ret = usb_submit_urb(cardp->rx_urb, GFP_ATOMIC))) {
		/* handle failure conditions */
		lbs_dev_dbg(1, &cardp->udev->dev, "Submit Rx URB failed\n");
		ret = -1;
	} else {
		lbs_dev_dbg(2, &cardp->udev->dev, "Submit Rx URB success\n");
		ret = 0;
	}

rx_ret:
	return ret;
}

static inline int if_usb_submit_rx_urb_fwload(wlan_private * priv)
{
	return __if_usb_submit_rx_urb(priv, &if_usb_receive_fwload);
}

static inline int if_usb_submit_rx_urb(wlan_private * priv)
{
	return __if_usb_submit_rx_urb(priv, &if_usb_receive);
}

static void if_usb_receive_fwload(struct urb *urb)
{
	struct read_cb_info *rinfo = (struct read_cb_info *)urb->context;
	wlan_private *priv = rinfo->priv;
	struct sk_buff *skb = rinfo->skb;
	struct usb_card_rec *cardp = (struct usb_card_rec *)priv->wlan_dev.card;
	struct fwsyncheader *syncfwheader;
	struct bootcmdrespStr bootcmdresp;

	if (urb->status) {
		lbs_dev_dbg(1, &cardp->udev->dev,
			    "URB status is failed during fw load\n");
		kfree_skb(skb);
		return;
	}

	if (cardp->bootcmdresp == 0) {
		memcpy (&bootcmdresp, skb->data + IPFIELD_ALIGN_OFFSET,
			sizeof(bootcmdresp));
		if (cardp->udev->descriptor.bcdDevice < 0x3106) {
			kfree_skb(skb);
			if_usb_submit_rx_urb_fwload(priv);
			cardp->bootcmdresp = 1;
			lbs_dev_dbg(1, &cardp->udev->dev,
				    "Received valid boot command response\n");
			return;
		}
		if (bootcmdresp.u32magicnumber != BOOT_CMD_MAGIC_NUMBER) {
			lbs_pr_info(
				"boot cmd response wrong magic number (0x%x)\n",
				bootcmdresp.u32magicnumber);
		} else if (bootcmdresp.u8cmd_tag != BOOT_CMD_FW_BY_USB) {
			lbs_pr_info(
				"boot cmd response cmd_tag error (%d)\n",
				bootcmdresp.u8cmd_tag);
		} else if (bootcmdresp.u8result != BOOT_CMD_RESP_OK) {
			lbs_pr_info(
				"boot cmd response result error (%d)\n",
				bootcmdresp.u8result);
		} else {
			cardp->bootcmdresp = 1;
			lbs_dev_dbg(1, &cardp->udev->dev,
				    "Received valid boot command response\n");
		}
		kfree_skb(skb);
		if_usb_submit_rx_urb_fwload(priv);
		return;
	}

	syncfwheader = kmalloc(sizeof(struct fwsyncheader), GFP_ATOMIC);
	if (!syncfwheader) {
		lbs_dev_dbg(1, &cardp->udev->dev, "Failure to allocate syncfwheader\n");
		kfree_skb(skb);
		return;
	}

	memcpy(syncfwheader, skb->data + IPFIELD_ALIGN_OFFSET,
			sizeof(struct fwsyncheader));

	if (!syncfwheader->cmd) {
		lbs_dev_dbg(2, &cardp->udev->dev,
			    "FW received Blk with correct CRC\n");
		lbs_dev_dbg(2, &cardp->udev->dev,
			    "FW received Blk seqnum = %d\n",
		       syncfwheader->seqnum);
		cardp->CRC_OK = 1;
	} else {
		lbs_dev_dbg(1, &cardp->udev->dev,
			    "FW received Blk with CRC error\n");
		cardp->CRC_OK = 0;
	}

	kfree_skb(skb);

	if (cardp->fwfinalblk) {
		cardp->fwdnldover = 1;
		goto exit;
	}

	if_prog_firmware(priv);

	if_usb_submit_rx_urb_fwload(priv);
exit:
	kfree(syncfwheader);

	return;

}

#define MRVDRV_MIN_PKT_LEN	30

static inline void process_cmdtypedata(int recvlength, struct sk_buff *skb,
				       struct usb_card_rec *cardp,
				       wlan_private *priv)
{
	if (recvlength > MRVDRV_ETH_RX_PACKET_BUFFER_SIZE +
	    MESSAGE_HEADER_LEN || recvlength < MRVDRV_MIN_PKT_LEN) {
		lbs_dev_dbg(1, &cardp->udev->dev,
			    "Packet length is Invalid\n");
		kfree_skb(skb);
		return;
	}

	skb_reserve(skb, IPFIELD_ALIGN_OFFSET);
	skb_put(skb, recvlength);
	skb_pull(skb, MESSAGE_HEADER_LEN);
	libertas_process_rxed_packet(priv, skb);
	priv->wlan_dev.upld_len = (recvlength - MESSAGE_HEADER_LEN);
}

static inline void process_cmdrequest(int recvlength, u8 *recvbuff,
				      struct sk_buff *skb,
				      struct usb_card_rec *cardp,
				      wlan_private *priv)
{
	u8 *cmdbuf;
	if (recvlength > MRVDRV_SIZE_OF_CMD_BUFFER) {
		lbs_dev_dbg(1, &cardp->udev->dev,
			    "The receive buffer is too large\n");
		kfree_skb(skb);
		return;
	}

	if (!in_interrupt())
		BUG();

	spin_lock(&priv->adapter->driver_lock);
	/* take care of cur_cmd = NULL case by reading the
	 * data to clear the interrupt */
	if (!priv->adapter->cur_cmd) {
		cmdbuf = priv->wlan_dev.upld_buf;
		priv->adapter->hisregcpy &= ~his_cmdupldrdy;
	} else
		cmdbuf = priv->adapter->cur_cmd->bufvirtualaddr;

	cardp->usb_int_cause |= his_cmdupldrdy;
	priv->wlan_dev.upld_len = (recvlength - MESSAGE_HEADER_LEN);
	memcpy(cmdbuf, recvbuff + MESSAGE_HEADER_LEN,
	       priv->wlan_dev.upld_len);

	kfree_skb(skb);
	libertas_interrupt(priv->wlan_dev.netdev);
	spin_unlock(&priv->adapter->driver_lock);

	lbs_dev_dbg(1, &cardp->udev->dev,
		    "Wake up main thread to handle cmd response\n");

	return;
}

/**
 *  @brief This function reads of the packet into the upload buff,
 *  wake up the main thread and initialise the Rx callack.
 *
 *  @param urb		pointer to struct urb
 *  @return 	   	N/A
 */
static void if_usb_receive(struct urb *urb)
{
	struct read_cb_info *rinfo = (struct read_cb_info *)urb->context;
	wlan_private *priv = rinfo->priv;
	struct sk_buff *skb = rinfo->skb;
	struct usb_card_rec *cardp = (struct usb_card_rec *)priv->wlan_dev.card;

	int recvlength = urb->actual_length;
	u8 *recvbuff = NULL;
	u32 recvtype;

	ENTER();

	if (recvlength) {
		if (urb->status) {
			lbs_dev_dbg(1, &cardp->udev->dev,
				    "URB status is failed\n");
			kfree_skb(skb);
			goto setup_for_next;
		}

		recvbuff = skb->data + IPFIELD_ALIGN_OFFSET;
		memcpy(&recvtype, recvbuff, sizeof(u32));
		lbs_dev_dbg(1, &cardp->udev->dev,
			    "Recv length = 0x%x\n", recvlength);
		lbs_dev_dbg(1, &cardp->udev->dev,
			    "Receive type = 0x%X\n", recvtype);
		recvtype = le32_to_cpu(recvtype);
		lbs_dev_dbg(1, &cardp->udev->dev,
			    "Receive type after = 0x%X\n", recvtype);
	} else if (urb->status)
		goto rx_exit;


	switch (recvtype) {
	case CMD_TYPE_DATA:
		process_cmdtypedata(recvlength, skb, cardp, priv);
		break;

	case CMD_TYPE_REQUEST:
		process_cmdrequest(recvlength, recvbuff, skb, cardp, priv);
		break;

	case CMD_TYPE_INDICATION:
		/* Event cause handling */
		spin_lock(&priv->adapter->driver_lock);
		cardp->usb_event_cause = *(u32 *) (recvbuff + MESSAGE_HEADER_LEN);
		lbs_dev_dbg(1, &cardp->udev->dev,"**EVENT** 0x%X\n",
			    cardp->usb_event_cause);
		if (cardp->usb_event_cause & 0xffff0000) {
			libertas_send_tx_feedback(priv);
			spin_unlock(&priv->adapter->driver_lock);
			break;
		}
		cardp->usb_event_cause = le32_to_cpu(cardp->usb_event_cause) << 3;
		cardp->usb_int_cause |= his_cardevent;
		kfree_skb(skb);
		libertas_interrupt(priv->wlan_dev.netdev);
		spin_unlock(&priv->adapter->driver_lock);
		goto rx_exit;
	default:
		kfree_skb(skb);
		break;
	}

setup_for_next:
	if_usb_submit_rx_urb(priv);
rx_exit:
	LEAVE();
	return;
}

/**
 *  @brief This function downloads data to FW
 *  @param priv		pointer to wlan_private structure
 *  @param type		type of data
 *  @param buf		pointer to data buffer
 *  @param len		number of bytes
 *  @return 	   	0 or -1
 */
int libertas_sbi_host_to_card(wlan_private * priv, u8 type, u8 * payload, u16 nb)
{
	int ret = -1;
	u32 tmp;
	struct usb_card_rec *cardp = (struct usb_card_rec *)priv->wlan_dev.card;

	lbs_dev_dbg(1, &cardp->udev->dev,"*** type = %u\n", type);
	lbs_dev_dbg(1, &cardp->udev->dev,"size after = %d\n", nb);

	if (type == MVMS_CMD) {
		tmp = cpu_to_le32(CMD_TYPE_REQUEST);
		priv->wlan_dev.dnld_sent = DNLD_CMD_SENT;
		memcpy(cardp->bulk_out_buffer, (u8 *) & tmp,
		       MESSAGE_HEADER_LEN);

	} else {
		tmp = cpu_to_le32(CMD_TYPE_DATA);
		priv->wlan_dev.dnld_sent = DNLD_DATA_SENT;
		memcpy(cardp->bulk_out_buffer, (u8 *) & tmp,
		       MESSAGE_HEADER_LEN);
	}

	memcpy((cardp->bulk_out_buffer + MESSAGE_HEADER_LEN), payload, nb);

	ret =
	    usb_tx_block(priv, cardp->bulk_out_buffer, nb + MESSAGE_HEADER_LEN);

	return ret;
}

/* called with adapter->driver_lock held */
int libertas_sbi_get_int_status(wlan_private * priv, u8 * ireg)
{
	struct usb_card_rec *cardp = priv->wlan_dev.card;

	*ireg = cardp->usb_int_cause;
	cardp->usb_int_cause = 0;

	lbs_dev_dbg(1, &cardp->udev->dev,"Int cause is 0x%X\n", *ireg);

	return 0;
}

int libertas_sbi_read_event_cause(wlan_private * priv)
{
	struct usb_card_rec *cardp = priv->wlan_dev.card;
	priv->adapter->eventcause = cardp->usb_event_cause;
	/* Re-submit rx urb here to avoid event lost issue */
	if_usb_submit_rx_urb(priv);
	return 0;
}

int reset_device(wlan_private *priv)
{
	int ret;

	ret = libertas_prepare_and_send_command(priv, cmd_802_11_reset,
				    cmd_act_halt, 0, 0, NULL);
	msleep_interruptible(10);

	return ret;
}

int libertas_sbi_unregister_dev(wlan_private * priv)
{
	int ret = 0;

	/* Need to send a Reset command to device before USB resources freed
	 * and wlan_remove_card() called, then device can handle FW download
	 * again.
	 */
	if (priv)
		reset_device(priv);

	return ret;
}


/**
 *  @brief  This function register usb device and initialize parameter
 *  @param		priv pointer to wlan_private
 *  @return		0 or -1
 */
int libertas_sbi_register_dev(wlan_private * priv)
{

	struct usb_card_rec *cardp = (struct usb_card_rec *)priv->wlan_dev.card;
	ENTER();

	cardp->priv = priv;
	cardp->eth_dev = priv->wlan_dev.netdev;
	priv->hotplug_device = &(cardp->udev->dev);

	SET_NETDEV_DEV(cardp->eth_dev, &(cardp->udev->dev));

	lbs_dev_dbg(1, &cardp->udev->dev, "udev pointer is at %p\n",
		    cardp->udev);

	LEAVE();
	return 0;
}



int libertas_sbi_prog_firmware(wlan_private * priv)
{
	struct usb_card_rec *cardp = priv->wlan_dev.card;
	int i = 0;
	static int reset_count = 10;

	ENTER();

	cardp->rinfo.priv = priv;

restart:
	if (if_usb_submit_rx_urb_fwload(priv) < 0) {
		lbs_dev_dbg(1, &cardp->udev->dev, "URB submission is failed\n");
		LEAVE();
		return -1;
	}

	cardp->bootcmdresp = 0;
	do {
		int j = 0;
		i++;
		/* Issue Boot command = 1, Boot from Download-FW */
		if_usb_issue_boot_command(priv, BOOT_CMD_FW_BY_USB);
		/* wait for command response */
		do {
			j++;
			msleep_interruptible(100);
		} while (cardp->bootcmdresp == 0 && j < 10);
	} while (cardp->bootcmdresp == 0 && i < 5);

	if (cardp->bootcmdresp == 0) {
		if (--reset_count >= 0) {
			libertas_do_reset(priv);
			goto restart;
		}
		return -1;
	}

	i = 0;
	priv->adapter->fw_ready = 0;

	cardp->totalbytes = 0;
	cardp->fwlastblksent = 0;
	cardp->CRC_OK = 1;
	cardp->fwdnldover = 0;
	cardp->fwseqnum = -1;
	cardp->totalbytes = 0;
	cardp->fwfinalblk = 0;

	if_prog_firmware(priv);

	do {
		lbs_dev_dbg(1, &cardp->udev->dev,"Wlan sched timeout\n");
		i++;
		msleep_interruptible(100);
		if (priv->adapter->surpriseremoved || i >= 20)
			break;
	} while (!cardp->fwdnldover);

	if (!cardp->fwdnldover) {
		lbs_pr_info("failed to load fw, resetting device!\n");
		if (--reset_count >= 0) {
			libertas_do_reset(priv);
			goto restart;
		}

		lbs_pr_info("FW download failure, time = %d ms\n", i * 100);
		LEAVE();
		return -1;
	}

	if_usb_submit_rx_urb(priv);

	/* Delay 200 ms to waiting for the FW ready */
	msleep_interruptible(200);

	priv->adapter->fw_ready = 1;

	LEAVE();
	return 0;
}

/**
 *  @brief Given a usb_card_rec return its wlan_private
 *  @param card		pointer to a usb_card_rec
 *  @return 	   	pointer to wlan_private
 */
wlan_private *libertas_sbi_get_priv(void *card)
{
	struct usb_card_rec *cardp = card;
	return cardp->priv;
}

#ifdef ENABLE_PM
int libertas_sbi_suspend(wlan_private * priv)
{
	return 0;
}

int libertas_sbi_resume(wlan_private * priv)
{
	return 0;
}
#endif

#ifdef CONFIG_PM
static int if_usb_suspend(struct usb_interface *intf, pm_message_t message)
{
	struct usb_card_rec *cardp = usb_get_intfdata(intf);
	wlan_private *priv = cardp->priv;

	ENTER();

	if (priv->adapter->psstate != PS_STATE_FULL_POWER)
		return -1;

	netif_device_detach(cardp->eth_dev);

	/* Unlink tx & rx urb */
	usb_kill_urb(cardp->tx_urb);
	usb_kill_urb(cardp->rx_urb);

	cardp->rx_urb_recall = 1;

	LEAVE();
	return 0;
}

static int if_usb_resume(struct usb_interface *intf)
{
	struct usb_card_rec *cardp = usb_get_intfdata(intf);

	ENTER();

	cardp->rx_urb_recall = 0;

	if_usb_submit_rx_urb(cardp->priv);

	netif_device_attach(cardp->eth_dev);

	LEAVE();
	return 0;
}
#else
#define if_usb_suspend NULL
#define if_usb_resume NULL
#endif

static struct usb_driver if_usb_driver = {
	/* driver name */
	.name = usbdriver_name,
	/* probe function name */
	.probe = if_usb_probe,
	/* disconnect function  name */
	.disconnect = if_usb_disconnect,
	/* device signature table */
	.id_table = if_usb_table,
	.suspend = if_usb_suspend,
	.resume = if_usb_resume,
};

/**
 *  @brief This function registers driver.
 *  @param add		pointer to add_card callback function
 *  @param remove	pointer to remove card callback function
 *  @param arg		pointer to call back function parameter
 *  @return 	   	dummy success variable
 */
int libertas_sbi_register(void)
{
	/*
	 * API registers the Marvell USB driver
	 * to the USB system
	 */
	usb_register(&if_usb_driver);

	/* Return success to wlan layer */
	return 0;
}

/**
 *  @brief This function removes usb driver.
 *  @return 	   	N/A
 */
void libertas_sbi_unregister(void)
{
	/* API unregisters the driver from USB subsystem */
	usb_deregister(&if_usb_driver);
	return;
}