Free Electrons

Embedded Linux Experts

  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
/*
 DVB device driver for em28xx

 (c) 2008 Mauro Carvalho Chehab <mchehab@infradead.org>

 (c) 2008 Devin Heitmueller <devin.heitmueller@gmail.com>
	- Fixes for the driver to properly work with HVR-950
	- Fixes for the driver to properly work with Pinnacle PCTV HD Pro Stick
	- Fixes for the driver to properly work with AMD ATI TV Wonder HD 600

 (c) 2008 Aidan Thornton <makosoft@googlemail.com>

 Based on cx88-dvb, saa7134-dvb and videobuf-dvb originally written by:
	(c) 2004, 2005 Chris Pascoe <c.pascoe@itee.uq.edu.au>
	(c) 2004 Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]

 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.
 */

#include <linux/kernel.h>
#include <linux/usb.h>

#include "em28xx.h"
#include <media/v4l2-common.h>
#include <media/videobuf-vmalloc.h>
#include <media/tuner.h>
#include "tuner-simple.h"

#include "lgdt330x.h"
#include "zl10353.h"
#include "s5h1409.h"
#include "mt352.h"
#include "mt352_priv.h" /* FIXME */
#include "tda1002x.h"

MODULE_DESCRIPTION("driver for em28xx based DVB cards");
MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@infradead.org>");
MODULE_LICENSE("GPL");

static unsigned int debug;
module_param(debug, int, 0644);
MODULE_PARM_DESC(debug, "enable debug messages [dvb]");

DVB_DEFINE_MOD_OPT_ADAPTER_NR(adapter_nr);

#define dprintk(level, fmt, arg...) do {			\
if (debug >= level) 						\
	printk(KERN_DEBUG "%s/2-dvb: " fmt, dev->name, ## arg);	\
} while (0)

#define EM28XX_DVB_NUM_BUFS 5
#define EM28XX_DVB_MAX_PACKETS 64

struct em28xx_dvb {
	struct dvb_frontend        *frontend;

	/* feed count management */
	struct mutex               lock;
	int                        nfeeds;

	/* general boilerplate stuff */
	struct dvb_adapter         adapter;
	struct dvb_demux           demux;
	struct dmxdev              dmxdev;
	struct dmx_frontend        fe_hw;
	struct dmx_frontend        fe_mem;
	struct dvb_net             net;
};


static inline void print_err_status(struct em28xx *dev,
				     int packet, int status)
{
	char *errmsg = "Unknown";

	switch (status) {
	case -ENOENT:
		errmsg = "unlinked synchronuously";
		break;
	case -ECONNRESET:
		errmsg = "unlinked asynchronuously";
		break;
	case -ENOSR:
		errmsg = "Buffer error (overrun)";
		break;
	case -EPIPE:
		errmsg = "Stalled (device not responding)";
		break;
	case -EOVERFLOW:
		errmsg = "Babble (bad cable?)";
		break;
	case -EPROTO:
		errmsg = "Bit-stuff error (bad cable?)";
		break;
	case -EILSEQ:
		errmsg = "CRC/Timeout (could be anything)";
		break;
	case -ETIME:
		errmsg = "Device does not respond";
		break;
	}
	if (packet < 0) {
		dprintk(1, "URB status %d [%s].\n", status, errmsg);
	} else {
		dprintk(1, "URB packet %d, status %d [%s].\n",
			packet, status, errmsg);
	}
}

static inline int dvb_isoc_copy(struct em28xx *dev, struct urb *urb)
{
	int i;

	if (!dev)
		return 0;

	if ((dev->state & DEV_DISCONNECTED) || (dev->state & DEV_MISCONFIGURED))
		return 0;

	if (urb->status < 0) {
		print_err_status(dev, -1, urb->status);
		if (urb->status == -ENOENT)
			return 0;
	}

	for (i = 0; i < urb->number_of_packets; i++) {
		int status = urb->iso_frame_desc[i].status;

		if (status < 0) {
			print_err_status(dev, i, status);
			if (urb->iso_frame_desc[i].status != -EPROTO)
				continue;
		}

		dvb_dmx_swfilter(&dev->dvb->demux, urb->transfer_buffer +
				 urb->iso_frame_desc[i].offset,
				 urb->iso_frame_desc[i].actual_length);
	}

	return 0;
}

static int start_streaming(struct em28xx_dvb *dvb)
{
	int rc;
	struct em28xx *dev = dvb->adapter.priv;
	int max_dvb_packet_size;

	usb_set_interface(dev->udev, 0, 1);
	rc = em28xx_set_mode(dev, EM28XX_DIGITAL_MODE);
	if (rc < 0)
		return rc;

	max_dvb_packet_size = em28xx_isoc_dvb_max_packetsize(dev);

	return em28xx_init_isoc(dev, EM28XX_DVB_MAX_PACKETS,
				EM28XX_DVB_NUM_BUFS, max_dvb_packet_size,
				dvb_isoc_copy);
}

static int stop_streaming(struct em28xx_dvb *dvb)
{
	struct em28xx *dev = dvb->adapter.priv;

	em28xx_uninit_isoc(dev);

	em28xx_set_mode(dev, EM28XX_SUSPEND);

	return 0;
}

static int start_feed(struct dvb_demux_feed *feed)
{
	struct dvb_demux *demux  = feed->demux;
	struct em28xx_dvb *dvb = demux->priv;
	int rc, ret;

	if (!demux->dmx.frontend)
		return -EINVAL;

	mutex_lock(&dvb->lock);
	dvb->nfeeds++;
	rc = dvb->nfeeds;

	if (dvb->nfeeds == 1) {
		ret = start_streaming(dvb);
		if (ret < 0)
			rc = ret;
	}

	mutex_unlock(&dvb->lock);
	return rc;
}

static int stop_feed(struct dvb_demux_feed *feed)
{
	struct dvb_demux *demux  = feed->demux;
	struct em28xx_dvb *dvb = demux->priv;
	int err = 0;

	mutex_lock(&dvb->lock);
	dvb->nfeeds--;

	if (0 == dvb->nfeeds)
		err = stop_streaming(dvb);

	mutex_unlock(&dvb->lock);
	return err;
}



/* ------------------------------------------------------------------ */
static int em28xx_dvb_bus_ctrl(struct dvb_frontend *fe, int acquire)
{
	struct em28xx *dev = fe->dvb->priv;

	if (acquire)
		return em28xx_set_mode(dev, EM28XX_DIGITAL_MODE);
	else
		return em28xx_set_mode(dev, EM28XX_SUSPEND);
}

/* ------------------------------------------------------------------ */

static struct lgdt330x_config em2880_lgdt3303_dev = {
	.demod_address = 0x0e,
	.demod_chip = LGDT3303,
};

static struct zl10353_config em28xx_zl10353_with_xc3028 = {
	.demod_address = (0x1e >> 1),
	.no_tuner = 1,
	.parallel_ts = 1,
	.if2 = 45600,
};

static struct s5h1409_config em28xx_s5h1409_with_xc3028 = {
	.demod_address = 0x32 >> 1,
	.output_mode   = S5H1409_PARALLEL_OUTPUT,
	.gpio          = S5H1409_GPIO_OFF,
	.inversion     = S5H1409_INVERSION_OFF,
	.status_mode   = S5H1409_DEMODLOCKING,
	.mpeg_timing   = S5H1409_MPEGTIMING_CONTINOUS_NONINVERTING_CLOCK
};

static struct zl10353_config em28xx_zl10353_xc3028_no_i2c_gate = {
	.demod_address = (0x1e >> 1),
	.no_tuner = 1,
	.disable_i2c_gate_ctrl = 1,
	.parallel_ts = 1,
	.if2 = 45600,
};

#ifdef EM28XX_DRX397XD_SUPPORT
/* [TODO] djh - not sure yet what the device config needs to contain */
static struct drx397xD_config em28xx_drx397xD_with_xc3028 = {
	.demod_address = (0xe0 >> 1),
};
#endif

static int mt352_terratec_xs_init(struct dvb_frontend *fe)
{
	/* Values extracted from a USB trace of the Terratec Windows driver */
	static u8 clock_config[]   = { CLOCK_CTL,  0x38, 0x2c };
	static u8 reset[]          = { RESET,      0x80 };
	static u8 adc_ctl_1_cfg[]  = { ADC_CTL_1,  0x40 };
	static u8 agc_cfg[]        = { AGC_TARGET, 0x28, 0xa0 };
	static u8 input_freq_cfg[] = { INPUT_FREQ_1, 0x31, 0xb8 };
	static u8 rs_err_cfg[]     = { RS_ERR_PER_1, 0x00, 0x4d };
	static u8 capt_range_cfg[] = { CAPT_RANGE, 0x32 };
	static u8 trl_nom_cfg[]    = { TRL_NOMINAL_RATE_1, 0x64, 0x00 };
	static u8 tps_given_cfg[]  = { TPS_GIVEN_1, 0x40, 0x80, 0x50 };
	static u8 tuner_go[]       = { TUNER_GO, 0x01};

	mt352_write(fe, clock_config,   sizeof(clock_config));
	udelay(200);
	mt352_write(fe, reset,          sizeof(reset));
	mt352_write(fe, adc_ctl_1_cfg,  sizeof(adc_ctl_1_cfg));
	mt352_write(fe, agc_cfg,        sizeof(agc_cfg));
	mt352_write(fe, input_freq_cfg, sizeof(input_freq_cfg));
	mt352_write(fe, rs_err_cfg,     sizeof(rs_err_cfg));
	mt352_write(fe, capt_range_cfg, sizeof(capt_range_cfg));
	mt352_write(fe, trl_nom_cfg,    sizeof(trl_nom_cfg));
	mt352_write(fe, tps_given_cfg,  sizeof(tps_given_cfg));
	mt352_write(fe, tuner_go,       sizeof(tuner_go));
	return 0;
}

static struct mt352_config terratec_xs_mt352_cfg = {
	.demod_address = (0x1e >> 1),
	.no_tuner = 1,
	.if2 = 45600,
	.demod_init = mt352_terratec_xs_init,
};

static struct tda10023_config em28xx_tda10023_config = {
	.demod_address = 0x0c,
	.invert = 1,
};

/* ------------------------------------------------------------------ */

static int attach_xc3028(u8 addr, struct em28xx *dev)
{
	struct dvb_frontend *fe;
	struct xc2028_config cfg;

	memset(&cfg, 0, sizeof(cfg));
	cfg.i2c_adap  = &dev->i2c_adap;
	cfg.i2c_addr  = addr;

	if (!dev->dvb->frontend) {
		printk(KERN_ERR "%s/2: dvb frontend not attached. "
				"Can't attach xc3028\n",
		       dev->name);
		return -EINVAL;
	}

	fe = dvb_attach(xc2028_attach, dev->dvb->frontend, &cfg);
	if (!fe) {
		printk(KERN_ERR "%s/2: xc3028 attach failed\n",
		       dev->name);
		dvb_frontend_detach(dev->dvb->frontend);
		dev->dvb->frontend = NULL;
		return -EINVAL;
	}

	printk(KERN_INFO "%s/2: xc3028 attached\n", dev->name);

	return 0;
}

/* ------------------------------------------------------------------ */

static int register_dvb(struct em28xx_dvb *dvb,
		 struct module *module,
		 struct em28xx *dev,
		 struct device *device)
{
	int result;

	mutex_init(&dvb->lock);

	/* register adapter */
	result = dvb_register_adapter(&dvb->adapter, dev->name, module, device,
				      adapter_nr);
	if (result < 0) {
		printk(KERN_WARNING "%s: dvb_register_adapter failed (errno = %d)\n",
		       dev->name, result);
		goto fail_adapter;
	}

	/* Ensure all frontends negotiate bus access */
	dvb->frontend->ops.ts_bus_ctrl = em28xx_dvb_bus_ctrl;

	dvb->adapter.priv = dev;

	/* register frontend */
	result = dvb_register_frontend(&dvb->adapter, dvb->frontend);
	if (result < 0) {
		printk(KERN_WARNING "%s: dvb_register_frontend failed (errno = %d)\n",
		       dev->name, result);
		goto fail_frontend;
	}

	/* register demux stuff */
	dvb->demux.dmx.capabilities =
		DMX_TS_FILTERING | DMX_SECTION_FILTERING |
		DMX_MEMORY_BASED_FILTERING;
	dvb->demux.priv       = dvb;
	dvb->demux.filternum  = 256;
	dvb->demux.feednum    = 256;
	dvb->demux.start_feed = start_feed;
	dvb->demux.stop_feed  = stop_feed;

	result = dvb_dmx_init(&dvb->demux);
	if (result < 0) {
		printk(KERN_WARNING "%s: dvb_dmx_init failed (errno = %d)\n",
		       dev->name, result);
		goto fail_dmx;
	}

	dvb->dmxdev.filternum    = 256;
	dvb->dmxdev.demux        = &dvb->demux.dmx;
	dvb->dmxdev.capabilities = 0;
	result = dvb_dmxdev_init(&dvb->dmxdev, &dvb->adapter);
	if (result < 0) {
		printk(KERN_WARNING "%s: dvb_dmxdev_init failed (errno = %d)\n",
		       dev->name, result);
		goto fail_dmxdev;
	}

	dvb->fe_hw.source = DMX_FRONTEND_0;
	result = dvb->demux.dmx.add_frontend(&dvb->demux.dmx, &dvb->fe_hw);
	if (result < 0) {
		printk(KERN_WARNING "%s: add_frontend failed (DMX_FRONTEND_0, errno = %d)\n",
		       dev->name, result);
		goto fail_fe_hw;
	}

	dvb->fe_mem.source = DMX_MEMORY_FE;
	result = dvb->demux.dmx.add_frontend(&dvb->demux.dmx, &dvb->fe_mem);
	if (result < 0) {
		printk(KERN_WARNING "%s: add_frontend failed (DMX_MEMORY_FE, errno = %d)\n",
		       dev->name, result);
		goto fail_fe_mem;
	}

	result = dvb->demux.dmx.connect_frontend(&dvb->demux.dmx, &dvb->fe_hw);
	if (result < 0) {
		printk(KERN_WARNING "%s: connect_frontend failed (errno = %d)\n",
		       dev->name, result);
		goto fail_fe_conn;
	}

	/* register network adapter */
	dvb_net_init(&dvb->adapter, &dvb->net, &dvb->demux.dmx);
	return 0;

fail_fe_conn:
	dvb->demux.dmx.remove_frontend(&dvb->demux.dmx, &dvb->fe_mem);
fail_fe_mem:
	dvb->demux.dmx.remove_frontend(&dvb->demux.dmx, &dvb->fe_hw);
fail_fe_hw:
	dvb_dmxdev_release(&dvb->dmxdev);
fail_dmxdev:
	dvb_dmx_release(&dvb->demux);
fail_dmx:
	dvb_unregister_frontend(dvb->frontend);
fail_frontend:
	dvb_frontend_detach(dvb->frontend);
	dvb_unregister_adapter(&dvb->adapter);
fail_adapter:
	return result;
}

static void unregister_dvb(struct em28xx_dvb *dvb)
{
	dvb_net_release(&dvb->net);
	dvb->demux.dmx.remove_frontend(&dvb->demux.dmx, &dvb->fe_mem);
	dvb->demux.dmx.remove_frontend(&dvb->demux.dmx, &dvb->fe_hw);
	dvb_dmxdev_release(&dvb->dmxdev);
	dvb_dmx_release(&dvb->demux);
	dvb_unregister_frontend(dvb->frontend);
	dvb_frontend_detach(dvb->frontend);
	dvb_unregister_adapter(&dvb->adapter);
}


static int dvb_init(struct em28xx *dev)
{
	int result = 0;
	struct em28xx_dvb *dvb;

	if (!dev->board.has_dvb) {
		/* This device does not support the extension */
		return 0;
	}

	dvb = kzalloc(sizeof(struct em28xx_dvb), GFP_KERNEL);

	if (dvb == NULL) {
		printk(KERN_INFO "em28xx_dvb: memory allocation failed\n");
		return -ENOMEM;
	}
	dev->dvb = dvb;

	em28xx_set_mode(dev, EM28XX_DIGITAL_MODE);
	/* init frontend */
	switch (dev->model) {
	case EM2883_BOARD_HAUPPAUGE_WINTV_HVR_850:
	case EM2883_BOARD_HAUPPAUGE_WINTV_HVR_950:
	case EM2880_BOARD_PINNACLE_PCTV_HD_PRO:
	case EM2880_BOARD_AMD_ATI_TV_WONDER_HD_600:
		dvb->frontend = dvb_attach(lgdt330x_attach,
					   &em2880_lgdt3303_dev,
					   &dev->i2c_adap);
		if (attach_xc3028(0x61, dev) < 0) {
			result = -EINVAL;
			goto out_free;
		}
		break;
	case EM2880_BOARD_KWORLD_DVB_310U:
		dvb->frontend = dvb_attach(zl10353_attach,
					   &em28xx_zl10353_with_xc3028,
					   &dev->i2c_adap);
		if (attach_xc3028(0x61, dev) < 0) {
			result = -EINVAL;
			goto out_free;
		}
		break;
	case EM2880_BOARD_HAUPPAUGE_WINTV_HVR_900:
	case EM2880_BOARD_EMPIRE_DUAL_TV:
		dvb->frontend = dvb_attach(zl10353_attach,
					   &em28xx_zl10353_xc3028_no_i2c_gate,
					   &dev->i2c_adap);
		if (attach_xc3028(0x61, dev) < 0) {
			result = -EINVAL;
			goto out_free;
		}
		break;
	case EM2880_BOARD_TERRATEC_HYBRID_XS:
	case EM2881_BOARD_PINNACLE_HYBRID_PRO:
		dvb->frontend = dvb_attach(zl10353_attach,
					   &em28xx_zl10353_xc3028_no_i2c_gate,
					   &dev->i2c_adap);
		if (dvb->frontend == NULL) {
			/* This board could have either a zl10353 or a mt352.
			   If the chip id isn't for zl10353, try mt352 */
			dvb->frontend = dvb_attach(mt352_attach,
						   &terratec_xs_mt352_cfg,
						   &dev->i2c_adap);
		}

		if (attach_xc3028(0x61, dev) < 0) {
			result = -EINVAL;
			goto out_free;
		}
		break;
	case EM2883_BOARD_KWORLD_HYBRID_330U:
	case EM2882_BOARD_EVGA_INDTUBE:
		dvb->frontend = dvb_attach(s5h1409_attach,
					   &em28xx_s5h1409_with_xc3028,
					   &dev->i2c_adap);
		if (attach_xc3028(0x61, dev) < 0) {
			result = -EINVAL;
			goto out_free;
		}
		break;
	case EM2882_BOARD_KWORLD_ATSC_315U:
		dvb->frontend = dvb_attach(lgdt330x_attach,
					   &em2880_lgdt3303_dev,
					   &dev->i2c_adap);
		if (dvb->frontend != NULL) {
			if (!dvb_attach(simple_tuner_attach, dvb->frontend,
				&dev->i2c_adap, 0x61, TUNER_THOMSON_DTT761X)) {
				result = -EINVAL;
				goto out_free;
			}
		}
		break;
	case EM2880_BOARD_HAUPPAUGE_WINTV_HVR_900_R2:
#ifdef EM28XX_DRX397XD_SUPPORT
		/* We don't have the config structure properly populated, so
		   this is commented out for now */
		dvb->frontend = dvb_attach(drx397xD_attach,
					   &em28xx_drx397xD_with_xc3028,
					   &dev->i2c_adap);
		if (attach_xc3028(0x61, dev) < 0) {
			result = -EINVAL;
			goto out_free;
		}
		break;
#endif
	case EM2870_BOARD_REDDO_DVB_C_USB_BOX:
		/* Philips CU1216L NIM (Philips TDA10023 + Infineon TUA6034) */
		dvb->frontend = dvb_attach(tda10023_attach,
			&em28xx_tda10023_config,
			&dev->i2c_adap, 0x48);
		if (dvb->frontend) {
			if (!dvb_attach(simple_tuner_attach, dvb->frontend,
				&dev->i2c_adap, 0x60, TUNER_PHILIPS_CU1216L)) {
				result = -EINVAL;
				goto out_free;
			}
		}
		break;
	default:
		printk(KERN_ERR "%s/2: The frontend of your DVB/ATSC card"
				" isn't supported yet\n",
		       dev->name);
		break;
	}
	if (NULL == dvb->frontend) {
		printk(KERN_ERR
		       "%s/2: frontend initialization failed\n",
		       dev->name);
		result = -EINVAL;
		goto out_free;
	}
	/* define general-purpose callback pointer */
	dvb->frontend->callback = em28xx_tuner_callback;

	/* register everything */
	result = register_dvb(dvb, THIS_MODULE, dev, &dev->udev->dev);

	if (result < 0)
		goto out_free;

	em28xx_set_mode(dev, EM28XX_SUSPEND);
	printk(KERN_INFO "Successfully loaded em28xx-dvb\n");
	return 0;

out_free:
	em28xx_set_mode(dev, EM28XX_SUSPEND);
	kfree(dvb);
	dev->dvb = NULL;
	return result;
}

static int dvb_fini(struct em28xx *dev)
{
	if (!dev->board.has_dvb) {
		/* This device does not support the extension */
		return 0;
	}

	if (dev->dvb) {
		unregister_dvb(dev->dvb);
		kfree(dev->dvb);
		dev->dvb = NULL;
	}

	return 0;
}

static struct em28xx_ops dvb_ops = {
	.id   = EM28XX_DVB,
	.name = "Em28xx dvb Extension",
	.init = dvb_init,
	.fini = dvb_fini,
};

static int __init em28xx_dvb_register(void)
{
	return em28xx_register_extension(&dvb_ops);
}

static void __exit em28xx_dvb_unregister(void)
{
	em28xx_unregister_extension(&dvb_ops);
}

module_init(em28xx_dvb_register);
module_exit(em28xx_dvb_unregister);