git.oblomov.eu Git - linux-2.6/blob - drivers/media/dvb/frontends/stb6100.c

   1 /*
   2         STB6100 Silicon Tuner
   3         Copyright (C) Manu Abraham (abraham.manu@gmail.com)
   4
   5         Copyright (C) ST Microelectronics
   6
   7         This program is free software; you can redistribute it and/or modify
   8         it under the terms of the GNU General Public License as published by
   9         the Free Software Foundation; either version 2 of the License, or
  10         (at your option) any later version.
  11
  12         This program is distributed in the hope that it will be useful,
  13         but WITHOUT ANY WARRANTY; without even the implied warranty of
  14         MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15         GNU General Public License for more details.
  16
  17         You should have received a copy of the GNU General Public License
  18         along with this program; if not, write to the Free Software
  19         Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22 #include <linux/init.h>
  23 #include <linux/kernel.h>
  24 #include <linux/module.h>
  25 #include <linux/string.h>
  26
  27 #include "dvb_frontend.h"
  28 #include "stb6100.h"
  29
  30 static unsigned int verbose;
  31 module_param(verbose, int, 0644);
  32
  33
  34 #define FE_ERROR                0
  35 #define FE_NOTICE               1
  36 #define FE_INFO                 2
  37 #define FE_DEBUG                3
  38
  39 #define dprintk(x, y, z, format, arg...) do {                                           \
  40         if (z) {                                                                        \
  41                 if      ((x > FE_ERROR) && (x > y))                                     \
  42                         printk(KERN_ERR "%s: " format "\n", __func__ , ##arg);          \
  43                 else if ((x > FE_NOTICE) && (x > y))                                    \
  44                         printk(KERN_NOTICE "%s: " format "\n", __func__ , ##arg);       \
  45                 else if ((x > FE_INFO) && (x > y))                                      \
  46                         printk(KERN_INFO "%s: " format "\n", __func__ , ##arg);         \
  47                 else if ((x > FE_DEBUG) && (x > y))                                     \
  48                         printk(KERN_DEBUG "%s: " format "\n", __func__ , ##arg);        \
  49         } else {                                                                        \
  50                 if (x > y)                                                              \
  51                         printk(format, ##arg);                                          \
  52         }                                                                               \
  53 } while(0)
  54
  55 struct stb6100_lkup {
  56         u32 val_low;
  57         u32 val_high;
  58         u8   reg;
  59 };
  60
  61 static int stb6100_release(struct dvb_frontend *fe);
  62
  63 static const struct stb6100_lkup lkup[] = {
  64         {       0,  950000, 0x0a },
  65         {  950000, 1000000, 0x0a },
  66         { 1000000, 1075000, 0x0c },
  67         { 1075000, 1200000, 0x00 },
  68         { 1200000, 1300000, 0x01 },
  69         { 1300000, 1370000, 0x02 },
  70         { 1370000, 1470000, 0x04 },
  71         { 1470000, 1530000, 0x05 },
  72         { 1530000, 1650000, 0x06 },
  73         { 1650000, 1800000, 0x08 },
  74         { 1800000, 1950000, 0x0a },
  75         { 1950000, 2150000, 0x0c },
  76         { 2150000, 9999999, 0x0c },
  77         {       0,       0, 0x00 }
  78 };
  79
  80 /* Register names for easy debugging.   */
  81 static const char *stb6100_regnames[] = {
  82         [STB6100_LD]            = "LD",
  83         [STB6100_VCO]           = "VCO",
  84         [STB6100_NI]            = "NI",
  85         [STB6100_NF_LSB]        = "NF",
  86         [STB6100_K]             = "K",
  87         [STB6100_G]             = "G",
  88         [STB6100_F]             = "F",
  89         [STB6100_DLB]           = "DLB",
  90         [STB6100_TEST1]         = "TEST1",
  91         [STB6100_FCCK]          = "FCCK",
  92         [STB6100_LPEN]          = "LPEN",
  93         [STB6100_TEST3]         = "TEST3",
  94 };
  95
  96 /* Template for normalisation, i.e. setting unused or undocumented
  97  * bits as required according to the documentation.
  98  */
  99 struct stb6100_regmask {
 100         u8 mask;
 101         u8 set;
 102 };
 103
 104 static const struct stb6100_regmask stb6100_template[] = {
 105         [STB6100_LD]            = { 0xff, 0x00 },
 106         [STB6100_VCO]           = { 0xff, 0x00 },
 107         [STB6100_NI]            = { 0xff, 0x00 },
 108         [STB6100_NF_LSB]        = { 0xff, 0x00 },
 109         [STB6100_K]             = { 0xc7, 0x38 },
 110         [STB6100_G]             = { 0xef, 0x10 },
 111         [STB6100_F]             = { 0x1f, 0xc0 },
 112         [STB6100_DLB]           = { 0x38, 0xc4 },
 113         [STB6100_TEST1]         = { 0x00, 0x8f },
 114         [STB6100_FCCK]          = { 0x40, 0x0d },
 115         [STB6100_LPEN]          = { 0xf0, 0x0b },
 116         [STB6100_TEST3]         = { 0x00, 0xde },
 117 };
 118
 119 static void stb6100_normalise_regs(u8 regs[])
 120 {
 121         int i;
 122
 123         for (i = 0; i < STB6100_NUMREGS; i++)
 124                 regs[i] = (regs[i] & stb6100_template[i].mask) | stb6100_template[i].set;
 125 }
 126
 127 static int stb6100_read_regs(struct stb6100_state *state, u8 regs[])
 128 {
 129         int rc;
 130         struct i2c_msg msg = {
 131                 .addr   = state->config->tuner_address,
 132                 .flags  = I2C_M_RD,
 133                 .buf    = regs,
 134                 .len    = STB6100_NUMREGS
 135         };
 136
 137         if (state->frontend->ops.i2c_gate_ctrl)
 138                 if ((rc = state->frontend->ops.i2c_gate_ctrl(state->frontend, 1)) < 0)
 139                         return rc;
 140
 141         rc = i2c_transfer(state->i2c, &msg, 1);
 142         if (state->frontend->ops.i2c_gate_ctrl) {
 143                 int rc2;
 144                 if ((rc2 = state->frontend->ops.i2c_gate_ctrl(state->frontend, 0)) < 0)
 145                         return rc2;
 146         }
 147         if (unlikely(rc != 1)) {
 148                 dprintk(verbose, FE_ERROR, 1, "Read (0x%x) err, rc=[%d]",
 149                         state->config->tuner_address, rc);
 150
 151                 return -EREMOTEIO;
 152         }
 153         if (unlikely(verbose > FE_DEBUG)) {
 154                 int i;
 155
 156                 dprintk(verbose, FE_DEBUG, 1, "    Read from 0x%02x", state->config->tuner_address);
 157                 for (i = 0; i < STB6100_NUMREGS; i++)
 158                         dprintk(verbose, FE_DEBUG, 1, "        %s: 0x%02x", stb6100_regnames[i], regs[i]);
 159         }
 160         return 0;
 161 }
 162
 163 static int stb6100_read_reg(struct stb6100_state *state, u8 reg)
 164 {
 165         u8 regs[STB6100_NUMREGS];
 166         int rc;
 167
 168         if (unlikely(reg >= STB6100_NUMREGS)) {
 169                 dprintk(verbose, FE_ERROR, 1, "Invalid register offset 0x%x", reg);
 170                 return -EINVAL;
 171         }
 172         if ((rc = stb6100_read_regs(state, regs)) < 0)
 173                 return rc;
 174         return (unsigned int)regs[reg];
 175 }
 176
 177 static int stb6100_write_reg_range(struct stb6100_state *state, u8 buf[], int start, int len)
 178 {
 179         int rc;
 180         u8 cmdbuf[len + 1];
 181         struct i2c_msg msg = {
 182                 .addr   = state->config->tuner_address,
 183                 .flags  = 0,
 184                 .buf    = cmdbuf,
 185                 .len    = len + 1
 186         };
 187
 188         if (unlikely(start < 1 || start + len > STB6100_NUMREGS)) {
 189                 dprintk(verbose, FE_ERROR, 1, "Invalid register range %d:%d",
 190                         start, len);
 191                 return -EINVAL;
 192         }
 193         memcpy(&cmdbuf[1], buf, len);
 194         cmdbuf[0] = start;
 195
 196         if (unlikely(verbose > FE_DEBUG)) {
 197                 int i;
 198
 199                 dprintk(verbose, FE_DEBUG, 1, "    Write @ 0x%02x: [%d:%d]", state->config->tuner_address, start, len);
 200                 for (i = 0; i < len; i++)
 201                         dprintk(verbose, FE_DEBUG, 1, "        %s: 0x%02x", stb6100_regnames[start + i], buf[i]);
 202         }
 203         if (state->frontend->ops.i2c_gate_ctrl)
 204                 if ((rc = state->frontend->ops.i2c_gate_ctrl(state->frontend, 1)) < 0)
 205                         return rc;
 206         rc = i2c_transfer(state->i2c, &msg, 1);
 207         if (state->frontend->ops.i2c_gate_ctrl) {
 208                 int rc2;
 209                 if ((rc2 = state->frontend->ops.i2c_gate_ctrl(state->frontend, 0)) < 0)
 210                         return rc2;
 211         }
 212         if (unlikely(rc != 1)) {
 213                 dprintk(verbose, FE_ERROR, 1, "(0x%x) write err [%d:%d], rc=[%d]",
 214                         (unsigned int)state->config->tuner_address, start, len, rc);
 215                 return -EREMOTEIO;
 216         }
 217         return 0;
 218 }
 219
 220 static int stb6100_write_reg(struct stb6100_state *state, u8 reg, u8 data)
 221 {
 222         if (unlikely(reg >= STB6100_NUMREGS)) {
 223                 dprintk(verbose, FE_ERROR, 1, "Invalid register offset 0x%x", reg);
 224                 return -EREMOTEIO;
 225         }
 226         data = (data & stb6100_template[reg].mask) | stb6100_template[reg].set;
 227         return stb6100_write_reg_range(state, &data, reg, 1);
 228 }
 229
 230 static int stb6100_write_regs(struct stb6100_state *state, u8 regs[])
 231 {
 232         stb6100_normalise_regs(regs);
 233         return stb6100_write_reg_range(state, &regs[1], 1, STB6100_NUMREGS - 1);
 234 }
 235
 236 static int stb6100_get_status(struct dvb_frontend *fe, u32 *status)
 237 {
 238         int rc;
 239         struct stb6100_state *state = fe->tuner_priv;
 240
 241         if ((rc = stb6100_read_reg(state, STB6100_LD)) < 0)
 242                 return rc;
 243
 244         return (rc & STB6100_LD_LOCK) ? TUNER_STATUS_LOCKED : 0;
 245 }
 246
 247 static int stb6100_get_bandwidth(struct dvb_frontend *fe, u32 *bandwidth)
 248 {
 249         int rc;
 250         u8 f;
 251         struct stb6100_state *state = fe->tuner_priv;
 252
 253         if ((rc = stb6100_read_reg(state, STB6100_F)) < 0)
 254                 return rc;
 255         f = rc & STB6100_F_F;
 256
 257         state->status.bandwidth = (f + 5) * 2000;       /* x2 for ZIF   */
 258
 259         *bandwidth = state->bandwidth = state->status.bandwidth * 1000;
 260         dprintk(verbose, FE_DEBUG, 1, "bandwidth = %u Hz", state->bandwidth);
 261         return 0;
 262 }
 263
 264 static int stb6100_set_bandwidth(struct dvb_frontend *fe, u32 bandwidth)
 265 {
 266         u32 tmp;
 267         int rc;
 268         struct stb6100_state *state = fe->tuner_priv;
 269
 270         dprintk(verbose, FE_DEBUG, 1, "set bandwidth to %u Hz", bandwidth);
 271
 272         bandwidth /= 2; /* ZIF */
 273
 274         if (bandwidth >= 36000000)      /* F[4:0] BW/2 max =31+5=36 mhz for F=31        */
 275                 tmp = 31;
 276         else if (bandwidth <= 5000000)  /* bw/2 min = 5Mhz for F=0                      */
 277                 tmp = 0;
 278         else                            /* if 5 < bw/2 < 36                             */
 279                 tmp = (bandwidth + 500000) / 1000000 - 5;
 280
 281         /* Turn on LPF bandwidth setting clock control,
 282          * set bandwidth, wait 10ms, turn off.
 283          */
 284         if ((rc = stb6100_write_reg(state, STB6100_FCCK, 0x0d | STB6100_FCCK_FCCK)) < 0)
 285                 return rc;
 286         if ((rc = stb6100_write_reg(state, STB6100_F, 0xc0 | tmp)) < 0)
 287                 return rc;
 288         msleep(1);
 289         if ((rc = stb6100_write_reg(state, STB6100_FCCK, 0x0d)) < 0)
 290                 return rc;
 291
 292         return 0;
 293 }
 294
 295 static int stb6100_get_frequency(struct dvb_frontend *fe, u32 *frequency)
 296 {
 297         int rc;
 298         u32 nint, nfrac, fvco;
 299         int psd2, odiv;
 300         struct stb6100_state *state = fe->tuner_priv;
 301         u8 regs[STB6100_NUMREGS];
 302
 303         if ((rc = stb6100_read_regs(state, regs)) < 0)
 304                 return rc;
 305
 306         odiv = (regs[STB6100_VCO] & STB6100_VCO_ODIV) >> STB6100_VCO_ODIV_SHIFT;
 307         psd2 = (regs[STB6100_K] & STB6100_K_PSD2) >> STB6100_K_PSD2_SHIFT;
 308         nint = regs[STB6100_NI];
 309         nfrac = ((regs[STB6100_K] & STB6100_K_NF_MSB) << 8) | regs[STB6100_NF_LSB];
 310         fvco = (nfrac * state->reference >> (9 - psd2)) + (nint * state->reference << psd2);
 311         *frequency = state->frequency = fvco >> (odiv + 1);
 312
 313         dprintk(verbose, FE_DEBUG, 1,
 314                 "frequency = %u kHz, odiv = %u, psd2 = %u, fxtal = %u kHz, fvco = %u kHz, N(I) = %u, N(F) = %u",
 315                 state->frequency, odiv, psd2, state->reference, fvco, nint, nfrac);
 316         return 0;
 317 }
 318
 319
 320 static int stb6100_set_frequency(struct dvb_frontend *fe, u32 frequency)
 321 {
 322         int rc;
 323         const struct stb6100_lkup *ptr;
 324         struct stb6100_state *state = fe->tuner_priv;
 325         struct dvbfe_params params;
 326
 327         u32 srate = 0, fvco, nint, nfrac;
 328         u8 regs[STB6100_NUMREGS];
 329         u8 g, psd2, odiv;
 330
 331         if ((rc = stb6100_read_regs(state, regs)) < 0)
 332                 return rc;
 333         if (fe->ops.get_params) {
 334                 dprintk(verbose, FE_DEBUG, 1, "Get Frontend parameters");
 335                 fe->ops.get_params(fe, &params);
 336         }
 337         switch (params.delivery) {
 338         case DVBFE_DELSYS_DVBS:
 339                 srate = params.delsys.dvbs.symbol_rate;
 340                 dprintk(verbose, FE_DEBUG, 1, "Delivery system = DVB-S, Symbol Rate=[%d]", srate);
 341                 break;
 342         case DVBFE_DELSYS_DSS:
 343                 dprintk(verbose, FE_DEBUG, 1, "Delivery system = DSS, Symbol Rate=[%d]", srate);
 344                 srate = params.delsys.dss.symbol_rate;
 345                 break;
 346         case DVBFE_DELSYS_DVBS2:
 347                 dprintk(verbose, FE_DEBUG, 1, "Delivery system = DVB-S2, Symbol Rate=[%d]", srate);
 348                 srate = params.delsys.dvbs2.symbol_rate;
 349                 break;
 350         default:
 351                 dprintk(verbose, FE_NOTICE, 1, "symbol rate unknown!");
 352                 srate = 22000000; /* just a typical default value       */
 353                 break;
 354         }
 355
 356         /* Baseband gain.       */
 357         if (srate >= 15000000)
 358                 g = 8;
 359         else if (state->srate >= 5000000)
 360                 g = 12;
 361         else
 362                 g = 14;
 363         regs[STB6100_G] = (regs[STB6100_G] & ~STB6100_G_G) | g;
 364
 365         /* VCO divide ratio (LO divide ratio, VCO prescaler enable).    */
 366         if (frequency <= 1075000)
 367                 odiv = 1;
 368         else
 369                 odiv = 0;
 370         regs[STB6100_VCO] = (regs[STB6100_VCO] & ~STB6100_VCO_ODIV) | (odiv << STB6100_VCO_ODIV_SHIFT);
 371
 372         if ((frequency > 1075000) && (frequency <= 1325000))
 373                 psd2 = 0;
 374         else
 375                 psd2 = 1;
 376         regs[STB6100_K] = (regs[STB6100_K] & ~STB6100_K_PSD2) | (psd2 << STB6100_K_PSD2_SHIFT);
 377
 378         /* OSM  */
 379         for (ptr = lkup;
 380              (ptr->val_high != 0) && !CHKRANGE(frequency, ptr->val_low, ptr->val_high);
 381              ptr++);
 382         if (ptr->val_high == 0) {
 383                 printk(KERN_ERR "%s: frequency out of range: %u kHz\n", __func__, frequency);
 384                 return -EINVAL;
 385         }
 386         regs[STB6100_VCO] = (regs[STB6100_VCO] & ~STB6100_VCO_OSM) | ptr->reg;
 387
 388         /* F(VCO) = F(LO) * (ODIV == 0 ? 2 : 4)                 */
 389         fvco = frequency << (1 + odiv);
 390         /* N(I) = floor(f(VCO) / (f(XTAL) * (PSD2 ? 2 : 1)))    */
 391         nint = fvco / (state->reference << psd2);
 392         /* N(F) = round(f(VCO) / f(XTAL) * (PSD2 ? 2 : 1) - N(I)) * 2 ^ 9       */
 393         nfrac = (((fvco - (nint * state->reference << psd2)) << (9 - psd2)) + state->reference / 2) / state->reference;
 394         dprintk(verbose, FE_DEBUG, 1,
 395                 "frequency = %u, srate = %u, g = %u, odiv = %u, psd2 = %u, fxtal = %u, osm = %u, fvco = %u, N(I) = %u, N(F) = %u",
 396                 frequency, srate, (unsigned int)g, (unsigned int)odiv,
 397                 (unsigned int)psd2, state->reference,
 398                 ptr->reg, fvco, nint, nfrac);
 399         regs[STB6100_NI] = nint;
 400         regs[STB6100_NF_LSB] = nfrac;
 401         regs[STB6100_K] = (regs[STB6100_K] & ~STB6100_K_NF_MSB) | ((nfrac >> 8) & STB6100_K_NF_MSB);
 402         regs[STB6100_VCO] |= STB6100_VCO_OSCH;          /* VCO search enabled           */
 403         regs[STB6100_VCO] |= STB6100_VCO_OCK;           /* VCO search clock off         */
 404         regs[STB6100_FCCK] |= STB6100_FCCK_FCCK;        /* LPF BW setting clock enabled */
 405         regs[STB6100_LPEN] &= ~STB6100_LPEN_LPEN;       /* PLL loop disabled            */
 406         /* Power up. */
 407         regs[STB6100_LPEN] |= STB6100_LPEN_SYNP | STB6100_LPEN_OSCP | STB6100_LPEN_BEN;
 408
 409         if ((rc = stb6100_write_regs(state, regs)) < 0)
 410                 return rc;
 411
 412         regs[STB6100_LPEN] |= STB6100_LPEN_LPEN;        /* PLL loop enabled             */
 413         if ((rc = stb6100_write_reg(state, STB6100_LPEN, regs[STB6100_LPEN])) < 0)
 414                 return rc;
 415
 416         regs[STB6100_VCO] &= ~STB6100_VCO_OCK;          /* VCO fast search              */
 417         if ((rc = stb6100_write_reg(state, STB6100_VCO, regs[STB6100_VCO])) < 0)
 418                 return rc;
 419
 420         msleep(5);                                      /* wait for LO to lock          */
 421         regs[STB6100_VCO] &= ~STB6100_VCO_OSCH;         /* vco search disabled          */
 422         regs[STB6100_VCO] |= STB6100_VCO_OCK;           /* search clock off             */
 423         if ((rc = stb6100_write_reg(state, STB6100_VCO, regs[STB6100_VCO])) < 0)
 424                 return rc;
 425         regs[STB6100_FCCK] &= ~STB6100_FCCK_FCCK;       /* LPF BW clock disabled        */
 426         if ((rc = stb6100_write_reg(state, STB6100_FCCK, regs[STB6100_FCCK])) < 0)
 427                 return rc;
 428
 429         msleep(30);
 430
 431         return 0;
 432 }
 433
 434 static int stb6100_sleep(struct dvb_frontend *fe)
 435 {
 436         /* TODO: power down     */
 437         return 0;
 438 }
 439
 440 static int stb6100_init(struct dvb_frontend *fe)
 441 {
 442         struct stb6100_state *state = fe->tuner_priv;
 443         struct tuner_state *status = &state->status;
 444
 445         status->tunerstep       = 125000;
 446         status->ifreq           = 0;
 447         status->refclock        = 27000000;     /* Hz   */
 448         status->iqsense         = 1;
 449         status->bandwidth       = 36000;        /* kHz  */
 450         state->bandwidth        = status->bandwidth * 1000;     /* MHz  */
 451         state->reference        = status->refclock / 1000;      /* kHz  */
 452
 453         /* Set default bandwidth.       */
 454         return stb6100_set_bandwidth(fe, status->bandwidth);
 455 }
 456
 457 static int stb6100_get_state(struct dvb_frontend *fe,
 458                              enum tuner_param param,
 459                              struct tuner_state *state)
 460 {
 461         switch (param) {
 462         case DVBFE_TUNER_FREQUENCY:
 463                 stb6100_get_frequency(fe, &state->frequency);
 464                 break;
 465         case DVBFE_TUNER_TUNERSTEP:
 466                 break;
 467         case DVBFE_TUNER_IFFREQ:
 468                 break;
 469         case DVBFE_TUNER_BANDWIDTH:
 470                 stb6100_get_bandwidth(fe, &state->bandwidth);
 471                 break;
 472         case DVBFE_TUNER_REFCLOCK:
 473                 break;
 474         default:
 475                 break;
 476         }
 477
 478         return 0;
 479 }
 480
 481 static int stb6100_set_state(struct dvb_frontend *fe,
 482                              enum tuner_param param,
 483                              struct tuner_state *state)
 484 {
 485         struct stb6100_state *tstate = fe->tuner_priv;
 486
 487         switch (param) {
 488         case DVBFE_TUNER_FREQUENCY:
 489                 stb6100_set_frequency(fe, state->frequency);
 490                 tstate->frequency = state->frequency;
 491                 break;
 492         case DVBFE_TUNER_TUNERSTEP:
 493                 break;
 494         case DVBFE_TUNER_IFFREQ:
 495                 break;
 496         case DVBFE_TUNER_BANDWIDTH:
 497                 stb6100_set_bandwidth(fe, state->bandwidth);
 498                 tstate->bandwidth = state->bandwidth;
 499                 break;
 500         case DVBFE_TUNER_REFCLOCK:
 501                 break;
 502         default:
 503                 break;
 504         }
 505
 506         return 0;
 507 }
 508
 509 static struct dvb_tuner_ops stb6100_ops = {
 510         .info = {
 511                 .name                   = "STB6100 Silicon Tuner",
 512                 .frequency_min          = 950000,
 513                 .frequency_max          = 2150000,
 514                 .frequency_step         = 0,
 515         },
 516
 517         .init           = stb6100_init,
 518         .sleep          = stb6100_sleep,
 519         .get_status     = stb6100_get_status,
 520         .get_state      = stb6100_get_state,
 521         .set_state      = stb6100_set_state,
 522         .release        = stb6100_release
 523 };
 524
 525 struct dvb_frontend *stb6100_attach(struct dvb_frontend *fe,
 526                                     struct stb6100_config *config,
 527                                     struct i2c_adapter *i2c)
 528 {
 529         struct stb6100_state *state = NULL;
 530
 531         state = kzalloc(sizeof (struct stb6100_state), GFP_KERNEL);
 532         if (state == NULL)
 533                 goto error;
 534
 535         state->config           = config;
 536         state->i2c              = i2c;
 537         state->frontend         = fe;
 538         state->reference        = config->refclock / 1000; /* kHz */
 539         fe->tuner_priv          = state;
 540         fe->ops.tuner_ops       = stb6100_ops;
 541
 542         printk("%s: Attaching STB6100 \n", __func__);
 543         return fe;
 544
 545 error:
 546         kfree(state);
 547         return NULL;
 548 }
 549
 550 static int stb6100_release(struct dvb_frontend *fe)
 551 {
 552         struct stb6100_state *state = fe->tuner_priv;
 553
 554         fe->tuner_priv = NULL;
 555         kfree(state);
 556
 557         return 0;
 558 }
 559
 560 EXPORT_SYMBOL(stb6100_attach);
 561 MODULE_PARM_DESC(verbose, "Set Verbosity level");
 562
 563 MODULE_AUTHOR("Manu Abraham");
 564 MODULE_DESCRIPTION("STB6100 Silicon tuner");
 565 MODULE_LICENSE("GPL");