drivers/media/video/em28xx/em28xx-dvb.c

   1 /*
   2  DVB device driver for em28xx
   3
   4  (c) 2008 Mauro Carvalho Chehab <mchehab@infradead.org>
   5
   6  (c) 2008 Devin Heitmueller <devin.heitmueller@gmail.com>
   7         - Fixes for the driver to properly work with HVR-950
   8         - Fixes for the driver to properly work with Pinnacle PCTV HD Pro Stick
   9         - Fixes for the driver to properly work with AMD ATI TV Wonder HD 600
  10
  11  (c) 2008 Aidan Thornton <makosoft@googlemail.com>
  12
  13  Based on cx88-dvb, saa7134-dvb and videobuf-dvb originally written by:
  14         (c) 2004, 2005 Chris Pascoe <c.pascoe@itee.uq.edu.au>
  15         (c) 2004 Gerd Knorr <kraxel@bytesex.org> [SuSE Labs]
  16
  17  This program is free software; you can redistribute it and/or modify
  18  it under the terms of the GNU General Public License as published by
  19  the Free Software Foundation; either version 2 of the License.
  20  */
  21
  22 #include <linux/kernel.h>
  23 #include <linux/usb.h>
  24
  25 #include "em28xx.h"
  26 #include <media/v4l2-common.h>
  27 #include <media/videobuf-vmalloc.h>
  28 #include <media/tuner.h>
  29 #include "tuner-simple.h"
  30
  31 #include "lgdt330x.h"
  32 #include "zl10353.h"
  33 #include "s5h1409.h"
  34 #include "mt352.h"
  35 #include "mt352_priv.h" /* FIXME */
  36
  37 MODULE_DESCRIPTION("driver for em28xx based DVB cards");
  38 MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@infradead.org>");
  39 MODULE_LICENSE("GPL");
  40
  41 static unsigned int debug;
  42 module_param(debug, int, 0644);
  43 MODULE_PARM_DESC(debug, "enable debug messages [dvb]");
  44
  45 DVB_DEFINE_MOD_OPT_ADAPTER_NR(adapter_nr);
  46
  47 #define dprintk(level, fmt, arg...) do {                        \
  48 if (debug >= level)                                             \
  49         printk(KERN_DEBUG "%s/2-dvb: " fmt, dev->name, ## arg); \
  50 } while (0)
  51
  52 #define EM28XX_DVB_NUM_BUFS 5
  53 #define EM28XX_DVB_MAX_PACKETS 64
  54
  55 struct em28xx_dvb {
  56         struct dvb_frontend        *frontend;
  57
  58         /* feed count management */
  59         struct mutex               lock;
  60         int                        nfeeds;
  61
  62         /* general boilerplate stuff */
  63         struct dvb_adapter         adapter;
  64         struct dvb_demux           demux;
  65         struct dmxdev              dmxdev;
  66         struct dmx_frontend        fe_hw;
  67         struct dmx_frontend        fe_mem;
  68         struct dvb_net             net;
  69 };
  70
  71
  72 static inline void print_err_status(struct em28xx *dev,
  73                                      int packet, int status)
  74 {
  75         char *errmsg = "Unknown";
  76
  77         switch (status) {
  78         case -ENOENT:
  79                 errmsg = "unlinked synchronuously";
  80                 break;
  81         case -ECONNRESET:
  82                 errmsg = "unlinked asynchronuously";
  83                 break;
  84         case -ENOSR:
  85                 errmsg = "Buffer error (overrun)";
  86                 break;
  87         case -EPIPE:
  88                 errmsg = "Stalled (device not responding)";
  89                 break;
  90         case -EOVERFLOW:
  91                 errmsg = "Babble (bad cable?)";
  92                 break;
  93         case -EPROTO:
  94                 errmsg = "Bit-stuff error (bad cable?)";
  95                 break;
  96         case -EILSEQ:
  97                 errmsg = "CRC/Timeout (could be anything)";
  98                 break;
  99         case -ETIME:
 100                 errmsg = "Device does not respond";
 101                 break;
 102         }
 103         if (packet < 0) {
 104                 dprintk(1, "URB status %d [%s].\n", status, errmsg);
 105         } else {
 106                 dprintk(1, "URB packet %d, status %d [%s].\n",
 107                         packet, status, errmsg);
 108         }
 109 }
 110
 111 static inline int dvb_isoc_copy(struct em28xx *dev, struct urb *urb)
 112 {
 113         int i;
 114
 115         if (!dev)
 116                 return 0;
 117
 118         if ((dev->state & DEV_DISCONNECTED) || (dev->state & DEV_MISCONFIGURED))
 119                 return 0;
 120
 121         if (urb->status < 0) {
 122                 print_err_status(dev, -1, urb->status);
 123                 if (urb->status == -ENOENT)
 124                         return 0;
 125         }
 126
 127         for (i = 0; i < urb->number_of_packets; i++) {
 128                 int status = urb->iso_frame_desc[i].status;
 129
 130                 if (status < 0) {
 131                         print_err_status(dev, i, status);
 132                         if (urb->iso_frame_desc[i].status != -EPROTO)
 133                                 continue;
 134                 }
 135
 136                 dvb_dmx_swfilter(&dev->dvb->demux, urb->transfer_buffer +
 137                                  urb->iso_frame_desc[i].offset,
 138                                  urb->iso_frame_desc[i].actual_length);
 139         }
 140
 141         return 0;
 142 }
 143
 144 static int start_streaming(struct em28xx_dvb *dvb)
 145 {
 146         int rc;
 147         struct em28xx *dev = dvb->adapter.priv;
 148         int max_dvb_packet_size;
 149
 150         usb_set_interface(dev->udev, 0, 1);
 151         rc = em28xx_set_mode(dev, EM28XX_DIGITAL_MODE);
 152         if (rc < 0)
 153                 return rc;
 154
 155         max_dvb_packet_size = em28xx_isoc_dvb_max_packetsize(dev);
 156
 157         return em28xx_init_isoc(dev, EM28XX_DVB_MAX_PACKETS,
 158                                 EM28XX_DVB_NUM_BUFS, max_dvb_packet_size,
 159                                 dvb_isoc_copy);
 160 }
 161
 162 static int stop_streaming(struct em28xx_dvb *dvb)
 163 {
 164         struct em28xx *dev = dvb->adapter.priv;
 165
 166         em28xx_uninit_isoc(dev);
 167
 168         em28xx_set_mode(dev, EM28XX_SUSPEND);
 169
 170         return 0;
 171 }
 172
 173 static int start_feed(struct dvb_demux_feed *feed)
 174 {
 175         struct dvb_demux *demux  = feed->demux;
 176         struct em28xx_dvb *dvb = demux->priv;
 177         int rc, ret;
 178
 179         if (!demux->dmx.frontend)
 180                 return -EINVAL;
 181
 182         mutex_lock(&dvb->lock);
 183         dvb->nfeeds++;
 184         rc = dvb->nfeeds;
 185
 186         if (dvb->nfeeds == 1) {
 187                 ret = start_streaming(dvb);
 188                 if (ret < 0)
 189                         rc = ret;
 190         }
 191
 192         mutex_unlock(&dvb->lock);
 193         return rc;
 194 }
 195
 196 static int stop_feed(struct dvb_demux_feed *feed)
 197 {
 198         struct dvb_demux *demux  = feed->demux;
 199         struct em28xx_dvb *dvb = demux->priv;
 200         int err = 0;
 201
 202         mutex_lock(&dvb->lock);
 203         dvb->nfeeds--;
 204
 205         if (0 == dvb->nfeeds)
 206                 err = stop_streaming(dvb);
 207
 208         mutex_unlock(&dvb->lock);
 209         return err;
 210 }
 211
 212
 213
 214 /* ------------------------------------------------------------------ */
 215 static int em28xx_dvb_bus_ctrl(struct dvb_frontend *fe, int acquire)
 216 {
 217         struct em28xx *dev = fe->dvb->priv;
 218
 219         if (acquire)
 220                 return em28xx_set_mode(dev, EM28XX_DIGITAL_MODE);
 221         else
 222                 return em28xx_set_mode(dev, EM28XX_SUSPEND);
 223 }
 224
 225 /* ------------------------------------------------------------------ */
 226
 227 static struct lgdt330x_config em2880_lgdt3303_dev = {
 228         .demod_address = 0x0e,
 229         .demod_chip = LGDT3303,
 230 };
 231
 232 static struct zl10353_config em28xx_zl10353_with_xc3028 = {
 233         .demod_address = (0x1e >> 1),
 234         .no_tuner = 1,
 235         .parallel_ts = 1,
 236         .if2 = 45600,
 237 };
 238
 239 static struct s5h1409_config em28xx_s5h1409_with_xc3028 = {
 240         .demod_address = 0x32 >> 1,
 241         .output_mode   = S5H1409_PARALLEL_OUTPUT,
 242         .gpio          = S5H1409_GPIO_OFF,
 243         .inversion     = S5H1409_INVERSION_OFF,
 244         .status_mode   = S5H1409_DEMODLOCKING,
 245         .mpeg_timing   = S5H1409_MPEGTIMING_CONTINOUS_NONINVERTING_CLOCK
 246 };
 247
 248 static struct zl10353_config em28xx_zl10353_xc3028_no_i2c_gate = {
 249         .demod_address = (0x1e >> 1),
 250         .no_tuner = 1,
 251         .disable_i2c_gate_ctrl = 1,
 252         .parallel_ts = 1,
 253         .if2 = 45600,
 254 };
 255
 256 #ifdef EM28XX_DRX397XD_SUPPORT
 257 /* [TODO] djh - not sure yet what the device config needs to contain */
 258 static struct drx397xD_config em28xx_drx397xD_with_xc3028 = {
 259         .demod_address = (0xe0 >> 1),
 260 };
 261 #endif
 262
 263 static int mt352_terratec_xs_init(struct dvb_frontend *fe)
 264 {
 265         /* Values extracted from a USB trace of the Terratec Windows driver */
 266         static u8 clock_config[]   = { CLOCK_CTL,  0x38, 0x2c };
 267         static u8 reset[]          = { RESET,      0x80 };
 268         static u8 adc_ctl_1_cfg[]  = { ADC_CTL_1,  0x40 };
 269         static u8 agc_cfg[]        = { AGC_TARGET, 0x28, 0xa0 };
 270         static u8 input_freq_cfg[] = { INPUT_FREQ_1, 0x31, 0xb8 };
 271         static u8 rs_err_cfg[]     = { RS_ERR_PER_1, 0x00, 0x4d };
 272         static u8 capt_range_cfg[] = { CAPT_RANGE, 0x32 };
 273         static u8 trl_nom_cfg[]    = { TRL_NOMINAL_RATE_1, 0x64, 0x00 };
 274         static u8 tps_given_cfg[]  = { TPS_GIVEN_1, 0x40, 0x80, 0x50 };
 275         static u8 tuner_go[]       = { TUNER_GO, 0x01};
 276
 277         mt352_write(fe, clock_config,   sizeof(clock_config));
 278         udelay(200);
 279         mt352_write(fe, reset,          sizeof(reset));
 280         mt352_write(fe, adc_ctl_1_cfg,  sizeof(adc_ctl_1_cfg));
 281         mt352_write(fe, agc_cfg,        sizeof(agc_cfg));
 282         mt352_write(fe, input_freq_cfg, sizeof(input_freq_cfg));
 283         mt352_write(fe, rs_err_cfg,     sizeof(rs_err_cfg));
 284         mt352_write(fe, capt_range_cfg, sizeof(capt_range_cfg));
 285         mt352_write(fe, trl_nom_cfg,    sizeof(trl_nom_cfg));
 286         mt352_write(fe, tps_given_cfg,  sizeof(tps_given_cfg));
 287         mt352_write(fe, tuner_go,       sizeof(tuner_go));
 288         return 0;
 289 }
 290
 291 static struct mt352_config terratec_xs_mt352_cfg = {
 292         .demod_address = (0x1e >> 1),
 293         .no_tuner = 1,
 294         .if2 = 45600,
 295         .demod_init = mt352_terratec_xs_init,
 296 };
 297
 298 /* ------------------------------------------------------------------ */
 299
 300 static int attach_xc3028(u8 addr, struct em28xx *dev)
 301 {
 302         struct dvb_frontend *fe;
 303         struct xc2028_config cfg;
 304
 305         memset(&cfg, 0, sizeof(cfg));
 306         cfg.i2c_adap  = &dev->i2c_adap;
 307         cfg.i2c_addr  = addr;
 308
 309         if (!dev->dvb->frontend) {
 310                 printk(KERN_ERR "%s/2: dvb frontend not attached. "
 311                                 "Can't attach xc3028\n",
 312                        dev->name);
 313                 return -EINVAL;
 314         }
 315
 316         fe = dvb_attach(xc2028_attach, dev->dvb->frontend, &cfg);
 317         if (!fe) {
 318                 printk(KERN_ERR "%s/2: xc3028 attach failed\n",
 319                        dev->name);
 320                 dvb_frontend_detach(dev->dvb->frontend);
 321                 dev->dvb->frontend = NULL;
 322                 return -EINVAL;
 323         }
 324
 325         printk(KERN_INFO "%s/2: xc3028 attached\n", dev->name);
 326
 327         return 0;
 328 }
 329
 330 /* ------------------------------------------------------------------ */
 331
 332 static int register_dvb(struct em28xx_dvb *dvb,
 333                  struct module *module,
 334                  struct em28xx *dev,
 335                  struct device *device)
 336 {
 337         int result;
 338
 339         mutex_init(&dvb->lock);
 340
 341         /* register adapter */
 342         result = dvb_register_adapter(&dvb->adapter, dev->name, module, device,
 343                                       adapter_nr);
 344         if (result < 0) {
 345                 printk(KERN_WARNING "%s: dvb_register_adapter failed (errno = %d)\n",
 346                        dev->name, result);
 347                 goto fail_adapter;
 348         }
 349
 350         /* Ensure all frontends negotiate bus access */
 351         dvb->frontend->ops.ts_bus_ctrl = em28xx_dvb_bus_ctrl;
 352
 353         dvb->adapter.priv = dev;
 354
 355         /* register frontend */
 356         result = dvb_register_frontend(&dvb->adapter, dvb->frontend);
 357         if (result < 0) {
 358                 printk(KERN_WARNING "%s: dvb_register_frontend failed (errno = %d)\n",
 359                        dev->name, result);
 360                 goto fail_frontend;
 361         }
 362
 363         /* register demux stuff */
 364         dvb->demux.dmx.capabilities =
 365                 DMX_TS_FILTERING | DMX_SECTION_FILTERING |
 366                 DMX_MEMORY_BASED_FILTERING;
 367         dvb->demux.priv       = dvb;
 368         dvb->demux.filternum  = 256;
 369         dvb->demux.feednum    = 256;
 370         dvb->demux.start_feed = start_feed;
 371         dvb->demux.stop_feed  = stop_feed;
 372
 373         result = dvb_dmx_init(&dvb->demux);
 374         if (result < 0) {
 375                 printk(KERN_WARNING "%s: dvb_dmx_init failed (errno = %d)\n",
 376                        dev->name, result);
 377                 goto fail_dmx;
 378         }
 379
 380         dvb->dmxdev.filternum    = 256;
 381         dvb->dmxdev.demux        = &dvb->demux.dmx;
 382         dvb->dmxdev.capabilities = 0;
 383         result = dvb_dmxdev_init(&dvb->dmxdev, &dvb->adapter);
 384         if (result < 0) {
 385                 printk(KERN_WARNING "%s: dvb_dmxdev_init failed (errno = %d)\n",
 386                        dev->name, result);
 387                 goto fail_dmxdev;
 388         }
 389
 390         dvb->fe_hw.source = DMX_FRONTEND_0;
 391         result = dvb->demux.dmx.add_frontend(&dvb->demux.dmx, &dvb->fe_hw);
 392         if (result < 0) {
 393                 printk(KERN_WARNING "%s: add_frontend failed (DMX_FRONTEND_0, errno = %d)\n",
 394                        dev->name, result);
 395                 goto fail_fe_hw;
 396         }
 397
 398         dvb->fe_mem.source = DMX_MEMORY_FE;
 399         result = dvb->demux.dmx.add_frontend(&dvb->demux.dmx, &dvb->fe_mem);
 400         if (result < 0) {
 401                 printk(KERN_WARNING "%s: add_frontend failed (DMX_MEMORY_FE, errno = %d)\n",
 402                        dev->name, result);
 403                 goto fail_fe_mem;
 404         }
 405
 406         result = dvb->demux.dmx.connect_frontend(&dvb->demux.dmx, &dvb->fe_hw);
 407         if (result < 0) {
 408                 printk(KERN_WARNING "%s: connect_frontend failed (errno = %d)\n",
 409                        dev->name, result);
 410                 goto fail_fe_conn;
 411         }
 412
 413         /* register network adapter */
 414         dvb_net_init(&dvb->adapter, &dvb->net, &dvb->demux.dmx);
 415         return 0;
 416
 417 fail_fe_conn:
 418         dvb->demux.dmx.remove_frontend(&dvb->demux.dmx, &dvb->fe_mem);
 419 fail_fe_mem:
 420         dvb->demux.dmx.remove_frontend(&dvb->demux.dmx, &dvb->fe_hw);
 421 fail_fe_hw:
 422         dvb_dmxdev_release(&dvb->dmxdev);
 423 fail_dmxdev:
 424         dvb_dmx_release(&dvb->demux);
 425 fail_dmx:
 426         dvb_unregister_frontend(dvb->frontend);
 427 fail_frontend:
 428         dvb_frontend_detach(dvb->frontend);
 429         dvb_unregister_adapter(&dvb->adapter);
 430 fail_adapter:
 431         return result;
 432 }
 433
 434 static void unregister_dvb(struct em28xx_dvb *dvb)
 435 {
 436         dvb_net_release(&dvb->net);
 437         dvb->demux.dmx.remove_frontend(&dvb->demux.dmx, &dvb->fe_mem);
 438         dvb->demux.dmx.remove_frontend(&dvb->demux.dmx, &dvb->fe_hw);
 439         dvb_dmxdev_release(&dvb->dmxdev);
 440         dvb_dmx_release(&dvb->demux);
 441         dvb_unregister_frontend(dvb->frontend);
 442         dvb_frontend_detach(dvb->frontend);
 443         dvb_unregister_adapter(&dvb->adapter);
 444 }
 445
 446
 447 static int dvb_init(struct em28xx *dev)
 448 {
 449         int result = 0;
 450         struct em28xx_dvb *dvb;
 451
 452         if (!dev->board.has_dvb) {
 453                 /* This device does not support the extension */
 454                 return 0;
 455         }
 456
 457         dvb = kzalloc(sizeof(struct em28xx_dvb), GFP_KERNEL);
 458
 459         if (dvb == NULL) {
 460                 printk(KERN_INFO "em28xx_dvb: memory allocation failed\n");
 461                 return -ENOMEM;
 462         }
 463         dev->dvb = dvb;
 464
 465         em28xx_set_mode(dev, EM28XX_DIGITAL_MODE);
 466         /* init frontend */
 467         switch (dev->model) {
 468         case EM2883_BOARD_HAUPPAUGE_WINTV_HVR_850:
 469         case EM2883_BOARD_HAUPPAUGE_WINTV_HVR_950:
 470         case EM2880_BOARD_PINNACLE_PCTV_HD_PRO:
 471         case EM2880_BOARD_AMD_ATI_TV_WONDER_HD_600:
 472                 dvb->frontend = dvb_attach(lgdt330x_attach,
 473                                            &em2880_lgdt3303_dev,
 474                                            &dev->i2c_adap);
 475                 if (attach_xc3028(0x61, dev) < 0) {
 476                         result = -EINVAL;
 477                         goto out_free;
 478                 }
 479                 break;
 480         case EM2880_BOARD_KWORLD_DVB_310U:
 481                 dvb->frontend = dvb_attach(zl10353_attach,
 482                                            &em28xx_zl10353_with_xc3028,
 483                                            &dev->i2c_adap);
 484                 if (attach_xc3028(0x61, dev) < 0) {
 485                         result = -EINVAL;
 486                         goto out_free;
 487                 }
 488                 break;
 489         case EM2880_BOARD_HAUPPAUGE_WINTV_HVR_900:
 490         case EM2880_BOARD_EMPIRE_DUAL_TV:
 491                 dvb->frontend = dvb_attach(zl10353_attach,
 492                                            &em28xx_zl10353_xc3028_no_i2c_gate,
 493                                            &dev->i2c_adap);
 494                 if (attach_xc3028(0x61, dev) < 0) {
 495                         result = -EINVAL;
 496                         goto out_free;
 497                 }
 498                 break;
 499         case EM2880_BOARD_TERRATEC_HYBRID_XS:
 500         case EM2881_BOARD_PINNACLE_HYBRID_PRO:
 501                 dvb->frontend = dvb_attach(zl10353_attach,
 502                                            &em28xx_zl10353_xc3028_no_i2c_gate,
 503                                            &dev->i2c_adap);
 504                 if (dvb->frontend == NULL) {
 505                         /* This board could have either a zl10353 or a mt352.
 506                            If the chip id isn't for zl10353, try mt352 */
 507                         dvb->frontend = dvb_attach(mt352_attach,
 508                                                    &terratec_xs_mt352_cfg,
 509                                                    &dev->i2c_adap);
 510                 }
 511
 512                 if (attach_xc3028(0x61, dev) < 0) {
 513                         result = -EINVAL;
 514                         goto out_free;
 515                 }
 516                 break;
 517         case EM2883_BOARD_KWORLD_HYBRID_330U:
 518         case EM2882_BOARD_EVGA_INDTUBE:
 519                 dvb->frontend = dvb_attach(s5h1409_attach,
 520                                            &em28xx_s5h1409_with_xc3028,
 521                                            &dev->i2c_adap);
 522                 if (attach_xc3028(0x61, dev) < 0) {
 523                         result = -EINVAL;
 524                         goto out_free;
 525                 }
 526                 break;
 527         case EM2882_BOARD_KWORLD_ATSC_315U:
 528                 dvb->frontend = dvb_attach(lgdt330x_attach,
 529                                            &em2880_lgdt3303_dev,
 530                                            &dev->i2c_adap);
 531                 if (dvb->frontend != NULL) {
 532                         if (!dvb_attach(simple_tuner_attach, dvb->frontend,
 533                                 &dev->i2c_adap, 0x61, TUNER_THOMSON_DTT761X)) {
 534                                 result = -EINVAL;
 535                                 goto out_free;
 536                         }
 537                 }
 538                 break;
 539         case EM2880_BOARD_HAUPPAUGE_WINTV_HVR_900_R2:
 540 #ifdef EM28XX_DRX397XD_SUPPORT
 541                 /* We don't have the config structure properly populated, so
 542                    this is commented out for now */
 543                 dvb->frontend = dvb_attach(drx397xD_attach,
 544                                            &em28xx_drx397xD_with_xc3028,
 545                                            &dev->i2c_adap);
 546                 if (attach_xc3028(0x61, dev) < 0) {
 547                         result = -EINVAL;
 548                         goto out_free;
 549                 }
 550                 break;
 551 #endif
 552         default:
 553                 printk(KERN_ERR "%s/2: The frontend of your DVB/ATSC card"
 554                                 " isn't supported yet\n",
 555                        dev->name);
 556                 break;
 557         }
 558         if (NULL == dvb->frontend) {
 559                 printk(KERN_ERR
 560                        "%s/2: frontend initialization failed\n",
 561                        dev->name);
 562                 result = -EINVAL;
 563                 goto out_free;
 564         }
 565         /* define general-purpose callback pointer */
 566         dvb->frontend->callback = em28xx_tuner_callback;
 567
 568         /* register everything */
 569         result = register_dvb(dvb, THIS_MODULE, dev, &dev->udev->dev);
 570
 571         if (result < 0)
 572                 goto out_free;
 573
 574         em28xx_set_mode(dev, EM28XX_SUSPEND);
 575         printk(KERN_INFO "Successfully loaded em28xx-dvb\n");
 576         return 0;
 577
 578 out_free:
 579         em28xx_set_mode(dev, EM28XX_SUSPEND);
 580         kfree(dvb);
 581         dev->dvb = NULL;
 582         return result;
 583 }
 584
 585 static int dvb_fini(struct em28xx *dev)
 586 {
 587         if (!dev->board.has_dvb) {
 588                 /* This device does not support the extension */
 589                 return 0;
 590         }
 591
 592         if (dev->dvb) {
 593                 unregister_dvb(dev->dvb);
 594                 dev->dvb = NULL;
 595         }
 596
 597         return 0;
 598 }
 599
 600 static struct em28xx_ops dvb_ops = {
 601         .id   = EM28XX_DVB,
 602         .name = "Em28xx dvb Extension",
 603         .init = dvb_init,
 604         .fini = dvb_fini,
 605 };
 606
 607 static int __init em28xx_dvb_register(void)
 608 {
 609         return em28xx_register_extension(&dvb_ops);
 610 }
 611
 612 static void __exit em28xx_dvb_unregister(void)
 613 {
 614         em28xx_unregister_extension(&dvb_ops);
 615 }
 616
 617 module_init(em28xx_dvb_register);
 618 module_exit(em28xx_dvb_unregister);