drivers/media/dvb/dvb-core/dvb_frontend.c

   1 /*
   2  * dvb_frontend.c: DVB frontend tuning interface/thread
   3  *
   4  *
   5  * Copyright (C) 1999-2001 Ralph  Metzler
   6  *                         Marcus Metzler
   7  *                         Holger Waechtler
   8  *                                    for convergence integrated media GmbH
   9  *
  10  * Copyright (C) 2004 Andrew de Quincey (tuning thread cleanup)
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  25  * Or, point your browser to http://www.gnu.org/copyleft/gpl.html
  26  */
  27
  28 #include <linux/string.h>
  29 #include <linux/kernel.h>
  30 #include <linux/sched.h>
  31 #include <linux/wait.h>
  32 #include <linux/slab.h>
  33 #include <linux/poll.h>
  34 #include <linux/module.h>
  35 #include <linux/moduleparam.h>
  36 #include <linux/list.h>
  37 #include <linux/suspend.h>
  38 #include <linux/jiffies.h>
  39 #include <asm/processor.h>
  40 #include <asm/semaphore.h>
  41
  42 #include "dvb_frontend.h"
  43 #include "dvbdev.h"
  44
  45 static int dvb_frontend_debug;
  46 static int dvb_shutdown_timeout = 5;
  47 static int dvb_force_auto_inversion;
  48 static int dvb_override_tune_delay;
  49 static int dvb_powerdown_on_sleep = 1;
  50
  51 module_param_named(frontend_debug, dvb_frontend_debug, int, 0644);
  52 MODULE_PARM_DESC(frontend_debug, "Turn on/off frontend core debugging (default:off).");
  53 module_param(dvb_shutdown_timeout, int, 0444);
  54 MODULE_PARM_DESC(dvb_shutdown_timeout, "wait <shutdown_timeout> seconds after close() before suspending hardware");
  55 module_param(dvb_force_auto_inversion, int, 0444);
  56 MODULE_PARM_DESC(dvb_force_auto_inversion, "0: normal (default), 1: INVERSION_AUTO forced always");
  57 module_param(dvb_override_tune_delay, int, 0444);
  58 MODULE_PARM_DESC(dvb_override_tune_delay, "0: normal (default), >0 => delay in milliseconds to wait for lock after a tune attempt");
  59 module_param(dvb_powerdown_on_sleep, int, 0444);
  60 MODULE_PARM_DESC(dvb_powerdown_on_sleep, "0: do not power down, 1: turn LNB volatage off on sleep (default)");
  61
  62 #define dprintk if (dvb_frontend_debug) printk
  63
  64 #define FESTATE_IDLE 1
  65 #define FESTATE_RETUNE 2
  66 #define FESTATE_TUNING_FAST 4
  67 #define FESTATE_TUNING_SLOW 8
  68 #define FESTATE_TUNED 16
  69 #define FESTATE_ZIGZAG_FAST 32
  70 #define FESTATE_ZIGZAG_SLOW 64
  71 #define FESTATE_DISEQC 128
  72 #define FESTATE_WAITFORLOCK (FESTATE_TUNING_FAST | FESTATE_TUNING_SLOW | FESTATE_ZIGZAG_FAST | FESTATE_ZIGZAG_SLOW | FESTATE_DISEQC)
  73 #define FESTATE_SEARCHING_FAST (FESTATE_TUNING_FAST | FESTATE_ZIGZAG_FAST)
  74 #define FESTATE_SEARCHING_SLOW (FESTATE_TUNING_SLOW | FESTATE_ZIGZAG_SLOW)
  75 #define FESTATE_LOSTLOCK (FESTATE_ZIGZAG_FAST | FESTATE_ZIGZAG_SLOW)
  76 /*
  77  * FESTATE_IDLE. No tuning parameters have been supplied and the loop is idling.
  78  * FESTATE_RETUNE. Parameters have been supplied, but we have not yet performed the first tune.
  79  * FESTATE_TUNING_FAST. Tuning parameters have been supplied and fast zigzag scan is in progress.
  80  * FESTATE_TUNING_SLOW. Tuning parameters have been supplied. Fast zigzag failed, so we're trying again, but slower.
  81  * FESTATE_TUNED. The frontend has successfully locked on.
  82  * FESTATE_ZIGZAG_FAST. The lock has been lost, and a fast zigzag has been initiated to try and regain it.
  83  * FESTATE_ZIGZAG_SLOW. The lock has been lost. Fast zigzag has been failed, so we're trying again, but slower.
  84  * FESTATE_DISEQC. A DISEQC command has just been issued.
  85  * FESTATE_WAITFORLOCK. When we're waiting for a lock.
  86  * FESTATE_SEARCHING_FAST. When we're searching for a signal using a fast zigzag scan.
  87  * FESTATE_SEARCHING_SLOW. When we're searching for a signal using a slow zigzag scan.
  88  * FESTATE_LOSTLOCK. When the lock has been lost, and we're searching it again.
  89  */
  90
  91 static DECLARE_MUTEX(frontend_mutex);
  92
  93 struct dvb_frontend_private {
  94
  95         struct dvb_device *dvbdev;
  96         struct dvb_frontend_parameters parameters;
  97         struct dvb_fe_events events;
  98         struct semaphore sem;
  99         struct list_head list_head;
 100         wait_queue_head_t wait_queue;
 101         pid_t thread_pid;
 102         unsigned long release_jiffies;
 103         int state;
 104         int bending;
 105         int lnb_drift;
 106         int inversion;
 107         int auto_step;
 108         int auto_sub_step;
 109         int started_auto_step;
 110         int min_delay;
 111         int max_drift;
 112         int step_size;
 113         int exit;
 114         int wakeup;
 115         fe_status_t status;
 116         fe_sec_tone_mode_t tone;
 117 };
 118
 119
 120 static void dvb_frontend_add_event(struct dvb_frontend *fe, fe_status_t status)
 121 {
 122         struct dvb_frontend_private *fepriv = fe->frontend_priv;
 123         struct dvb_fe_events *events = &fepriv->events;
 124         struct dvb_frontend_event *e;
 125         int wp;
 126
 127         dprintk ("%s\n", __FUNCTION__);
 128
 129         if (down_interruptible (&events->sem))
 130                 return;
 131
 132         wp = (events->eventw + 1) % MAX_EVENT;
 133
 134         if (wp == events->eventr) {
 135                 events->overflow = 1;
 136                 events->eventr = (events->eventr + 1) % MAX_EVENT;
 137         }
 138
 139         e = &events->events[events->eventw];
 140
 141         memcpy (&e->parameters, &fepriv->parameters,
 142                 sizeof (struct dvb_frontend_parameters));
 143
 144         if (status & FE_HAS_LOCK)
 145                 if (fe->ops->get_frontend)
 146                         fe->ops->get_frontend(fe, &e->parameters);
 147
 148         events->eventw = wp;
 149
 150         up (&events->sem);
 151
 152         e->status = status;
 153
 154         wake_up_interruptible (&events->wait_queue);
 155 }
 156
 157 static int dvb_frontend_get_event(struct dvb_frontend *fe,
 158                             struct dvb_frontend_event *event, int flags)
 159 {
 160         struct dvb_frontend_private *fepriv = fe->frontend_priv;
 161         struct dvb_fe_events *events = &fepriv->events;
 162
 163         dprintk ("%s\n", __FUNCTION__);
 164
 165         if (events->overflow) {
 166                 events->overflow = 0;
 167                 return -EOVERFLOW;
 168         }
 169
 170         if (events->eventw == events->eventr) {
 171                 int ret;
 172
 173                 if (flags & O_NONBLOCK)
 174                         return -EWOULDBLOCK;
 175
 176                 up(&fepriv->sem);
 177
 178                 ret = wait_event_interruptible (events->wait_queue,
 179                                                 events->eventw != events->eventr);
 180
 181                 if (down_interruptible (&fepriv->sem))
 182                         return -ERESTARTSYS;
 183
 184                 if (ret < 0)
 185                         return ret;
 186         }
 187
 188         if (down_interruptible (&events->sem))
 189                 return -ERESTARTSYS;
 190
 191         memcpy (event, &events->events[events->eventr],
 192                 sizeof(struct dvb_frontend_event));
 193
 194         events->eventr = (events->eventr + 1) % MAX_EVENT;
 195
 196         up (&events->sem);
 197
 198         return 0;
 199 }
 200
 201 static void dvb_frontend_init(struct dvb_frontend *fe)
 202 {
 203         dprintk ("DVB: initialising frontend %i (%s)...\n",
 204                  fe->dvb->num,
 205                  fe->ops->info.name);
 206
 207         if (fe->ops->init)
 208                 fe->ops->init(fe);
 209 }
 210
 211 static void update_delay(int *quality, int *delay, int min_delay, int locked)
 212 {
 213             int q2;
 214
 215             dprintk ("%s\n", __FUNCTION__);
 216
 217             if (locked)
 218                       (*quality) = (*quality * 220 + 36*256) / 256;
 219             else
 220                       (*quality) = (*quality * 220 + 0) / 256;
 221
 222             q2 = *quality - 128;
 223             q2 *= q2;
 224
 225             *delay = min_delay + q2 * HZ / (128*128);
 226 }
 227
 228 /**
 229  * Performs automatic twiddling of frontend parameters.
 230  *
 231  * @param fe The frontend concerned.
 232  * @param check_wrapped Checks if an iteration has completed. DO NOT SET ON THE FIRST ATTEMPT
 233  * @returns Number of complete iterations that have been performed.
 234  */
 235 static int dvb_frontend_autotune(struct dvb_frontend *fe, int check_wrapped)
 236 {
 237         int autoinversion;
 238         int ready = 0;
 239         struct dvb_frontend_private *fepriv = fe->frontend_priv;
 240         int original_inversion = fepriv->parameters.inversion;
 241         u32 original_frequency = fepriv->parameters.frequency;
 242
 243         /* are we using autoinversion? */
 244         autoinversion = ((!(fe->ops->info.caps & FE_CAN_INVERSION_AUTO)) &&
 245                          (fepriv->parameters.inversion == INVERSION_AUTO));
 246
 247         /* setup parameters correctly */
 248         while(!ready) {
 249                 /* calculate the lnb_drift */
 250                 fepriv->lnb_drift = fepriv->auto_step * fepriv->step_size;
 251
 252                 /* wrap the auto_step if we've exceeded the maximum drift */
 253                 if (fepriv->lnb_drift > fepriv->max_drift) {
 254                         fepriv->auto_step = 0;
 255                         fepriv->auto_sub_step = 0;
 256                         fepriv->lnb_drift = 0;
 257                 }
 258
 259                 /* perform inversion and +/- zigzag */
 260                 switch(fepriv->auto_sub_step) {
 261                 case 0:
 262                         /* try with the current inversion and current drift setting */
 263                         ready = 1;
 264                         break;
 265
 266                 case 1:
 267                         if (!autoinversion) break;
 268
 269                         fepriv->inversion = (fepriv->inversion == INVERSION_OFF) ? INVERSION_ON : INVERSION_OFF;
 270                         ready = 1;
 271                         break;
 272
 273                 case 2:
 274                         if (fepriv->lnb_drift == 0) break;
 275
 276                         fepriv->lnb_drift = -fepriv->lnb_drift;
 277                         ready = 1;
 278                         break;
 279
 280                 case 3:
 281                         if (fepriv->lnb_drift == 0) break;
 282                         if (!autoinversion) break;
 283
 284                         fepriv->inversion = (fepriv->inversion == INVERSION_OFF) ? INVERSION_ON : INVERSION_OFF;
 285                         fepriv->lnb_drift = -fepriv->lnb_drift;
 286                         ready = 1;
 287                         break;
 288
 289                 default:
 290                         fepriv->auto_step++;
 291                         fepriv->auto_sub_step = -1; /* it'll be incremented to 0 in a moment */
 292                         break;
 293                 }
 294
 295                 if (!ready) fepriv->auto_sub_step++;
 296         }
 297
 298         /* if this attempt would hit where we started, indicate a complete
 299          * iteration has occurred */
 300         if ((fepriv->auto_step == fepriv->started_auto_step) &&
 301             (fepriv->auto_sub_step == 0) && check_wrapped) {
 302                 return 1;
 303         }
 304
 305         dprintk("%s: drift:%i inversion:%i auto_step:%i "
 306                 "auto_sub_step:%i started_auto_step:%i\n",
 307                 __FUNCTION__, fepriv->lnb_drift, fepriv->inversion,
 308                 fepriv->auto_step, fepriv->auto_sub_step, fepriv->started_auto_step);
 309
 310         /* set the frontend itself */
 311         fepriv->parameters.frequency += fepriv->lnb_drift;
 312         if (autoinversion)
 313                 fepriv->parameters.inversion = fepriv->inversion;
 314         if (fe->ops->set_frontend)
 315                 fe->ops->set_frontend(fe, &fepriv->parameters);
 316
 317         fepriv->parameters.frequency = original_frequency;
 318         fepriv->parameters.inversion = original_inversion;
 319
 320         fepriv->auto_sub_step++;
 321         return 0;
 322 }
 323
 324 static int dvb_frontend_is_exiting(struct dvb_frontend *fe)
 325 {
 326         struct dvb_frontend_private *fepriv = fe->frontend_priv;
 327
 328         if (fepriv->exit)
 329                 return 1;
 330
 331         if (fepriv->dvbdev->writers == 1)
 332                 if (time_after(jiffies, fepriv->release_jiffies +
 333                                         dvb_shutdown_timeout * HZ))
 334                         return 1;
 335
 336         return 0;
 337 }
 338
 339 static int dvb_frontend_should_wakeup(struct dvb_frontend *fe)
 340 {
 341         struct dvb_frontend_private *fepriv = fe->frontend_priv;
 342
 343         if (fepriv->wakeup) {
 344                 fepriv->wakeup = 0;
 345                 return 1;
 346         }
 347         return dvb_frontend_is_exiting(fe);
 348 }
 349
 350 static void dvb_frontend_wakeup(struct dvb_frontend *fe)
 351 {
 352         struct dvb_frontend_private *fepriv = fe->frontend_priv;
 353
 354         fepriv->wakeup = 1;
 355         wake_up_interruptible(&fepriv->wait_queue);
 356 }
 357
 358 /*
 359  * FIXME: use linux/kthread.h
 360  */
 361 static int dvb_frontend_thread(void *data)
 362 {
 363         struct dvb_frontend *fe = data;
 364         struct dvb_frontend_private *fepriv = fe->frontend_priv;
 365         unsigned long timeout;
 366         char name [15];
 367         int quality = 0, delay = 3*HZ;
 368         fe_status_t s;
 369         int check_wrapped = 0;
 370
 371         dprintk("%s\n", __FUNCTION__);
 372
 373         snprintf (name, sizeof(name), "kdvb-fe-%i", fe->dvb->num);
 374
 375         lock_kernel();
 376         daemonize(name);
 377         sigfillset(&current->blocked);
 378         unlock_kernel();
 379
 380         fepriv->status = 0;
 381         dvb_frontend_init(fe);
 382         fepriv->wakeup = 0;
 383
 384         while (1) {
 385                 up(&fepriv->sem);           /* is locked when we enter the thread... */
 386
 387                 timeout = wait_event_interruptible_timeout(fepriv->wait_queue,
 388                                                            dvb_frontend_should_wakeup(fe),
 389                                                            delay);
 390                 if (0 != dvb_frontend_is_exiting(fe)) {
 391                         /* got signal or quitting */
 392                         break;
 393                 }
 394
 395                 try_to_freeze();
 396
 397                 if (down_interruptible(&fepriv->sem))
 398                         break;
 399
 400                 /* if we've got no parameters, just keep idling */
 401                 if (fepriv->state & FESTATE_IDLE) {
 402                         delay = 3*HZ;
 403                         quality = 0;
 404                         continue;
 405                 }
 406
 407                 /* get the frontend status */
 408                 if (fepriv->state & FESTATE_RETUNE) {
 409                         s = 0;
 410                 } else {
 411                         if (fe->ops->read_status)
 412                                 fe->ops->read_status(fe, &s);
 413                         if (s != fepriv->status) {
 414                                 dvb_frontend_add_event(fe, s);
 415                                 fepriv->status = s;
 416                         }
 417                 }
 418                 /* if we're not tuned, and we have a lock, move to the TUNED state */
 419                 if ((fepriv->state & FESTATE_WAITFORLOCK) && (s & FE_HAS_LOCK)) {
 420                         update_delay(&quality, &delay, fepriv->min_delay, s & FE_HAS_LOCK);
 421                         fepriv->state = FESTATE_TUNED;
 422
 423                         /* if we're tuned, then we have determined the correct inversion */
 424                         if ((!(fe->ops->info.caps & FE_CAN_INVERSION_AUTO)) &&
 425                             (fepriv->parameters.inversion == INVERSION_AUTO)) {
 426                                 fepriv->parameters.inversion = fepriv->inversion;
 427                         }
 428                         continue;
 429                 }
 430
 431                 /* if we are tuned already, check we're still locked */
 432                 if (fepriv->state & FESTATE_TUNED) {
 433                         update_delay(&quality, &delay, fepriv->min_delay, s & FE_HAS_LOCK);
 434
 435                         /* we're tuned, and the lock is still good... */
 436                         if (s & FE_HAS_LOCK)
 437                                 continue;
 438                         else { /* if we _WERE_ tuned, but now don't have a lock */
 439                                 fepriv->state = FESTATE_ZIGZAG_FAST;
 440                                 fepriv->started_auto_step = fepriv->auto_step;
 441                                 check_wrapped = 0;
 442                         }
 443                 }
 444
 445                 /* don't actually do anything if we're in the LOSTLOCK state,
 446                  * the frontend is set to FE_CAN_RECOVER, and the max_drift is 0 */
 447                 if ((fepriv->state & FESTATE_LOSTLOCK) &&
 448                     (fe->ops->info.caps & FE_CAN_RECOVER) && (fepriv->max_drift == 0)) {
 449                         update_delay(&quality, &delay, fepriv->min_delay, s & FE_HAS_LOCK);
 450                         continue;
 451                 }
 452
 453                 /* don't do anything if we're in the DISEQC state, since this
 454                  * might be someone with a motorized dish controlled by DISEQC.
 455                  * If its actually a re-tune, there will be a SET_FRONTEND soon enough. */
 456                 if (fepriv->state & FESTATE_DISEQC) {
 457                         update_delay(&quality, &delay, fepriv->min_delay, s & FE_HAS_LOCK);
 458                         continue;
 459                 }
 460
 461                 /* if we're in the RETUNE state, set everything up for a brand
 462                  * new scan, keeping the current inversion setting, as the next
 463                  * tune is _very_ likely to require the same */
 464                 if (fepriv->state & FESTATE_RETUNE) {
 465                         fepriv->lnb_drift = 0;
 466                         fepriv->auto_step = 0;
 467                         fepriv->auto_sub_step = 0;
 468                         fepriv->started_auto_step = 0;
 469                         check_wrapped = 0;
 470                 }
 471
 472                 /* fast zigzag. */
 473                 if ((fepriv->state & FESTATE_SEARCHING_FAST) || (fepriv->state & FESTATE_RETUNE)) {
 474                         delay = fepriv->min_delay;
 475
 476                         /* peform a tune */
 477                         if (dvb_frontend_autotune(fe, check_wrapped)) {
 478                                 /* OK, if we've run out of trials at the fast speed.
 479                                  * Drop back to slow for the _next_ attempt */
 480                                 fepriv->state = FESTATE_SEARCHING_SLOW;
 481                                 fepriv->started_auto_step = fepriv->auto_step;
 482                                 continue;
 483                         }
 484                         check_wrapped = 1;
 485
 486                         /* if we've just retuned, enter the ZIGZAG_FAST state.
 487                          * This ensures we cannot return from an
 488                          * FE_SET_FRONTEND ioctl before the first frontend tune
 489                          * occurs */
 490                         if (fepriv->state & FESTATE_RETUNE) {
 491                                 fepriv->state = FESTATE_TUNING_FAST;
 492                         }
 493                 }
 494
 495                 /* slow zigzag */
 496                 if (fepriv->state & FESTATE_SEARCHING_SLOW) {
 497                         update_delay(&quality, &delay, fepriv->min_delay, s & FE_HAS_LOCK);
 498
 499                         /* Note: don't bother checking for wrapping; we stay in this
 500                          * state until we get a lock */
 501                         dvb_frontend_autotune(fe, 0);
 502                 }
 503         }
 504
 505         if (dvb_shutdown_timeout) {
 506                 if (dvb_powerdown_on_sleep)
 507                         if (fe->ops->set_voltage)
 508                                 fe->ops->set_voltage(fe, SEC_VOLTAGE_OFF);
 509                 if (fe->ops->sleep)
 510                         fe->ops->sleep(fe);
 511         }
 512
 513         fepriv->thread_pid = 0;
 514         mb();
 515
 516         dvb_frontend_wakeup(fe);
 517         return 0;
 518 }
 519
 520 static void dvb_frontend_stop(struct dvb_frontend *fe)
 521 {
 522         unsigned long ret;
 523         struct dvb_frontend_private *fepriv = fe->frontend_priv;
 524
 525         dprintk ("%s\n", __FUNCTION__);
 526
 527         fepriv->exit = 1;
 528         mb();
 529
 530         if (!fepriv->thread_pid)
 531                 return;
 532
 533         /* check if the thread is really alive */
 534         if (kill_proc(fepriv->thread_pid, 0, 1) == -ESRCH) {
 535                 printk("dvb_frontend_stop: thread PID %d already died\n",
 536                                 fepriv->thread_pid);
 537                 /* make sure the mutex was not held by the thread */
 538                 init_MUTEX (&fepriv->sem);
 539                 return;
 540         }
 541
 542         /* wake up the frontend thread, so it notices that fe->exit == 1 */
 543         dvb_frontend_wakeup(fe);
 544
 545         /* wait until the frontend thread has exited */
 546         ret = wait_event_interruptible(fepriv->wait_queue,0 == fepriv->thread_pid);
 547         if (-ERESTARTSYS != ret) {
 548                 fepriv->state = FESTATE_IDLE;
 549                 return;
 550         }
 551         fepriv->state = FESTATE_IDLE;
 552
 553         /* paranoia check in case a signal arrived */
 554         if (fepriv->thread_pid)
 555                 printk("dvb_frontend_stop: warning: thread PID %d won't exit\n",
 556                                 fepriv->thread_pid);
 557 }
 558
 559 s32 timeval_usec_diff(struct timeval lasttime, struct timeval curtime)
 560 {
 561         return ((curtime.tv_usec < lasttime.tv_usec) ?
 562                 1000000 - lasttime.tv_usec + curtime.tv_usec :
 563                 curtime.tv_usec - lasttime.tv_usec);
 564 }
 565 EXPORT_SYMBOL(timeval_usec_diff);
 566
 567 static inline void timeval_usec_add(struct timeval *curtime, u32 add_usec)
 568 {
 569         curtime->tv_usec += add_usec;
 570         if (curtime->tv_usec >= 1000000) {
 571                 curtime->tv_usec -= 1000000;
 572                 curtime->tv_sec++;
 573         }
 574 }
 575
 576 /*
 577  * Sleep until gettimeofday() > waketime + add_usec
 578  * This needs to be as precise as possible, but as the delay is
 579  * usually between 2ms and 32ms, it is done using a scheduled msleep
 580  * followed by usleep (normally a busy-wait loop) for the remainder
 581  */
 582 void dvb_frontend_sleep_until(struct timeval *waketime, u32 add_usec)
 583 {
 584         struct timeval lasttime;
 585         s32 delta, newdelta;
 586
 587         timeval_usec_add(waketime, add_usec);
 588
 589         do_gettimeofday(&lasttime);
 590         delta = timeval_usec_diff(lasttime, *waketime);
 591         if (delta > 2500) {
 592                 msleep((delta - 1500) / 1000);
 593                 do_gettimeofday(&lasttime);
 594                 newdelta = timeval_usec_diff(lasttime, *waketime);
 595                 delta = (newdelta > delta) ? 0 : newdelta;
 596         }
 597         if (delta > 0)
 598                 udelay(delta);
 599 }
 600 EXPORT_SYMBOL(dvb_frontend_sleep_until);
 601
 602 static int dvb_frontend_start(struct dvb_frontend *fe)
 603 {
 604         int ret;
 605         struct dvb_frontend_private *fepriv = fe->frontend_priv;
 606
 607         dprintk ("%s\n", __FUNCTION__);
 608
 609         if (fepriv->thread_pid) {
 610                 if (!fepriv->exit)
 611                         return 0;
 612                 else
 613                         dvb_frontend_stop (fe);
 614         }
 615
 616         if (signal_pending(current))
 617                 return -EINTR;
 618         if (down_interruptible (&fepriv->sem))
 619                 return -EINTR;
 620
 621         fepriv->state = FESTATE_IDLE;
 622         fepriv->exit = 0;
 623         fepriv->thread_pid = 0;
 624         mb();
 625
 626         ret = kernel_thread (dvb_frontend_thread, fe, 0);
 627
 628         if (ret < 0) {
 629                 printk("dvb_frontend_start: failed to start kernel_thread (%d)\n", ret);
 630                 up(&fepriv->sem);
 631                 return ret;
 632         }
 633         fepriv->thread_pid = ret;
 634
 635         return 0;
 636 }
 637
 638 static int dvb_frontend_ioctl(struct inode *inode, struct file *file,
 639                         unsigned int cmd, void *parg)
 640 {
 641         struct dvb_device *dvbdev = file->private_data;
 642         struct dvb_frontend *fe = dvbdev->priv;
 643         struct dvb_frontend_private *fepriv = fe->frontend_priv;
 644         int err = -EOPNOTSUPP;
 645
 646         dprintk ("%s\n", __FUNCTION__);
 647
 648         if (!fe || fepriv->exit)
 649                 return -ENODEV;
 650
 651         if ((file->f_flags & O_ACCMODE) == O_RDONLY &&
 652             (_IOC_DIR(cmd) != _IOC_READ || cmd == FE_GET_EVENT ||
 653              cmd == FE_DISEQC_RECV_SLAVE_REPLY))
 654                 return -EPERM;
 655
 656         if (down_interruptible (&fepriv->sem))
 657                 return -ERESTARTSYS;
 658
 659         switch (cmd) {
 660         case FE_GET_INFO: {
 661                 struct dvb_frontend_info* info = parg;
 662                 memcpy(info, &fe->ops->info, sizeof(struct dvb_frontend_info));
 663
 664                 /* Force the CAN_INVERSION_AUTO bit on. If the frontend doesn't
 665                  * do it, it is done for it. */
 666                 info->caps |= FE_CAN_INVERSION_AUTO;
 667                 err = 0;
 668                 break;
 669         }
 670
 671         case FE_READ_STATUS: {
 672                 fe_status_t* status = parg;
 673
 674                 /* if retune was requested but hasn't occured yet, prevent
 675                  * that user get signal state from previous tuning */
 676                 if(fepriv->state == FESTATE_RETUNE) {
 677                         err=0;
 678                         *status = 0;
 679                         break;
 680                 }
 681
 682                 if (fe->ops->read_status)
 683                         err = fe->ops->read_status(fe, status);
 684                 break;
 685         }
 686         case FE_READ_BER:
 687                 if (fe->ops->read_ber)
 688                         err = fe->ops->read_ber(fe, (__u32*) parg);
 689                 break;
 690
 691         case FE_READ_SIGNAL_STRENGTH:
 692                 if (fe->ops->read_signal_strength)
 693                         err = fe->ops->read_signal_strength(fe, (__u16*) parg);
 694                 break;
 695
 696         case FE_READ_SNR:
 697                 if (fe->ops->read_snr)
 698                         err = fe->ops->read_snr(fe, (__u16*) parg);
 699                 break;
 700
 701         case FE_READ_UNCORRECTED_BLOCKS:
 702                 if (fe->ops->read_ucblocks)
 703                         err = fe->ops->read_ucblocks(fe, (__u32*) parg);
 704                 break;
 705
 706
 707         case FE_DISEQC_RESET_OVERLOAD:
 708                 if (fe->ops->diseqc_reset_overload) {
 709                         err = fe->ops->diseqc_reset_overload(fe);
 710                         fepriv->state = FESTATE_DISEQC;
 711                         fepriv->status = 0;
 712                 }
 713                 break;
 714
 715         case FE_DISEQC_SEND_MASTER_CMD:
 716                 if (fe->ops->diseqc_send_master_cmd) {
 717                         err = fe->ops->diseqc_send_master_cmd(fe, (struct dvb_diseqc_master_cmd*) parg);
 718                         fepriv->state = FESTATE_DISEQC;
 719                         fepriv->status = 0;
 720                 }
 721                 break;
 722
 723         case FE_DISEQC_SEND_BURST:
 724                 if (fe->ops->diseqc_send_burst) {
 725                         err = fe->ops->diseqc_send_burst(fe, (fe_sec_mini_cmd_t) parg);
 726                         fepriv->state = FESTATE_DISEQC;
 727                         fepriv->status = 0;
 728                 }
 729                 break;
 730
 731         case FE_SET_TONE:
 732                 if (fe->ops->set_tone) {
 733                         err = fe->ops->set_tone(fe, (fe_sec_tone_mode_t) parg);
 734                         fepriv->state = FESTATE_DISEQC;
 735                         fepriv->status = 0;
 736                         fepriv->tone = (fe_sec_tone_mode_t) parg;
 737                 }
 738                 break;
 739
 740         case FE_SET_VOLTAGE:
 741                 if (fe->ops->set_voltage) {
 742                         err = fe->ops->set_voltage(fe, (fe_sec_voltage_t) parg);
 743                         fepriv->state = FESTATE_DISEQC;
 744                         fepriv->status = 0;
 745                 }
 746                 break;
 747
 748         case FE_DISHNETWORK_SEND_LEGACY_CMD:
 749                 if (fe->ops->dishnetwork_send_legacy_command) {
 750                         err = fe->ops->dishnetwork_send_legacy_command(fe, (unsigned int) parg);
 751                         fepriv->state = FESTATE_DISEQC;
 752                         fepriv->status = 0;
 753                 } else if (fe->ops->set_voltage) {
 754                         /*
 755                          * NOTE: This is a fallback condition.  Some frontends
 756                          * (stv0299 for instance) take longer than 8msec to
 757                          * respond to a set_voltage command.  Those switches
 758                          * need custom routines to switch properly.  For all
 759                          * other frontends, the following shoule work ok.
 760                          * Dish network legacy switches (as used by Dish500)
 761                          * are controlled by sending 9-bit command words
 762                          * spaced 8msec apart.
 763                          * the actual command word is switch/port dependant
 764                          * so it is up to the userspace application to send
 765                          * the right command.
 766                          * The command must always start with a '0' after
 767                          * initialization, so parg is 8 bits and does not
 768                          * include the initialization or start bit
 769                          */
 770                         unsigned int cmd = ((unsigned int) parg) << 1;
 771                         struct timeval nexttime;
 772                         struct timeval tv[10];
 773                         int i;
 774                         u8 last = 1;
 775                         if (dvb_frontend_debug)
 776                                 printk("%s switch command: 0x%04x\n", __FUNCTION__, cmd);
 777                         do_gettimeofday(&nexttime);
 778                         if (dvb_frontend_debug)
 779                                 memcpy(&tv[0], &nexttime, sizeof(struct timeval));
 780                         /* before sending a command, initialize by sending
 781                          * a 32ms 18V to the switch
 782                          */
 783                         fe->ops->set_voltage(fe, SEC_VOLTAGE_18);
 784                         dvb_frontend_sleep_until(&nexttime, 32000);
 785
 786                         for (i = 0; i < 9; i++) {
 787                                 if (dvb_frontend_debug)
 788                                         do_gettimeofday(&tv[i + 1]);
 789                                 if ((cmd & 0x01) != last) {
 790                                         /* set voltage to (last ? 13V : 18V) */
 791                                         fe->ops->set_voltage(fe, (last) ? SEC_VOLTAGE_13 : SEC_VOLTAGE_18);
 792                                         last = (last) ? 0 : 1;
 793                                 }
 794                                 cmd = cmd >> 1;
 795                                 if (i != 8)
 796                                         dvb_frontend_sleep_until(&nexttime, 8000);
 797                         }
 798                         if (dvb_frontend_debug) {
 799                                 printk("%s(%d): switch delay (should be 32k followed by all 8k\n",
 800                                         __FUNCTION__, fe->dvb->num);
 801                                 for (i = 1; i < 10; i++)
 802                                         printk("%d: %d\n", i, timeval_usec_diff(tv[i-1] , tv[i]));
 803                         }
 804                         err = 0;
 805                         fepriv->state = FESTATE_DISEQC;
 806                         fepriv->status = 0;
 807                 }
 808                 break;
 809
 810         case FE_DISEQC_RECV_SLAVE_REPLY:
 811                 if (fe->ops->diseqc_recv_slave_reply)
 812                         err = fe->ops->diseqc_recv_slave_reply(fe, (struct dvb_diseqc_slave_reply*) parg);
 813                 break;
 814
 815         case FE_ENABLE_HIGH_LNB_VOLTAGE:
 816                 if (fe->ops->enable_high_lnb_voltage)
 817                         err = fe->ops->enable_high_lnb_voltage(fe, (int) parg);
 818                 break;
 819
 820         case FE_SET_FRONTEND: {
 821                 struct dvb_frontend_tune_settings fetunesettings;
 822
 823                 memcpy (&fepriv->parameters, parg,
 824                         sizeof (struct dvb_frontend_parameters));
 825
 826                 memset(&fetunesettings, 0, sizeof(struct dvb_frontend_tune_settings));
 827                 memcpy(&fetunesettings.parameters, parg,
 828                        sizeof (struct dvb_frontend_parameters));
 829
 830                 /* force auto frequency inversion if requested */
 831                 if (dvb_force_auto_inversion) {
 832                         fepriv->parameters.inversion = INVERSION_AUTO;
 833                         fetunesettings.parameters.inversion = INVERSION_AUTO;
 834                 }
 835                 if (fe->ops->info.type == FE_OFDM) {
 836                         /* without hierachical coding code_rate_LP is irrelevant,
 837                          * so we tolerate the otherwise invalid FEC_NONE setting */
 838                         if (fepriv->parameters.u.ofdm.hierarchy_information == HIERARCHY_NONE &&
 839                             fepriv->parameters.u.ofdm.code_rate_LP == FEC_NONE)
 840                                 fepriv->parameters.u.ofdm.code_rate_LP = FEC_AUTO;
 841                 }
 842
 843                 /* get frontend-specific tuning settings */
 844                 if (fe->ops->get_tune_settings && (fe->ops->get_tune_settings(fe, &fetunesettings) == 0)) {
 845                         fepriv->min_delay = (fetunesettings.min_delay_ms * HZ) / 1000;
 846                         fepriv->max_drift = fetunesettings.max_drift;
 847                         fepriv->step_size = fetunesettings.step_size;
 848                 } else {
 849                         /* default values */
 850                         switch(fe->ops->info.type) {
 851                         case FE_QPSK:
 852                                 fepriv->min_delay = HZ/20;
 853                                 fepriv->step_size = fepriv->parameters.u.qpsk.symbol_rate / 16000;
 854                                 fepriv->max_drift = fepriv->parameters.u.qpsk.symbol_rate / 2000;
 855                                 break;
 856
 857                         case FE_QAM:
 858                                 fepriv->min_delay = HZ/20;
 859                                 fepriv->step_size = 0; /* no zigzag */
 860                                 fepriv->max_drift = 0;
 861                                 break;
 862
 863                         case FE_OFDM:
 864                                 fepriv->min_delay = HZ/20;
 865                                 fepriv->step_size = fe->ops->info.frequency_stepsize * 2;
 866                                 fepriv->max_drift = (fe->ops->info.frequency_stepsize * 2) + 1;
 867                                 break;
 868                         case FE_ATSC:
 869                                 printk("dvb-core: FE_ATSC not handled yet.\n");
 870                                 break;
 871                         }
 872                 }
 873                 if (dvb_override_tune_delay > 0)
 874                         fepriv->min_delay = (dvb_override_tune_delay * HZ) / 1000;
 875
 876                 fepriv->state = FESTATE_RETUNE;
 877                 dvb_frontend_wakeup(fe);
 878                 dvb_frontend_add_event(fe, 0);
 879                 fepriv->status = 0;
 880                 err = 0;
 881                 break;
 882         }
 883
 884         case FE_GET_EVENT:
 885                 err = dvb_frontend_get_event (fe, parg, file->f_flags);
 886                 break;
 887
 888         case FE_GET_FRONTEND:
 889                 if (fe->ops->get_frontend) {
 890                         memcpy (parg, &fepriv->parameters, sizeof (struct dvb_frontend_parameters));
 891                         err = fe->ops->get_frontend(fe, (struct dvb_frontend_parameters*) parg);
 892                 }
 893                 break;
 894         };
 895
 896         up (&fepriv->sem);
 897         return err;
 898 }
 899
 900 static unsigned int dvb_frontend_poll(struct file *file, struct poll_table_struct *wait)
 901 {
 902         struct dvb_device *dvbdev = file->private_data;
 903         struct dvb_frontend *fe = dvbdev->priv;
 904         struct dvb_frontend_private *fepriv = fe->frontend_priv;
 905
 906         dprintk ("%s\n", __FUNCTION__);
 907
 908         poll_wait (file, &fepriv->events.wait_queue, wait);
 909
 910         if (fepriv->events.eventw != fepriv->events.eventr)
 911                 return (POLLIN | POLLRDNORM | POLLPRI);
 912
 913         return 0;
 914 }
 915
 916 static int dvb_frontend_open(struct inode *inode, struct file *file)
 917 {
 918         struct dvb_device *dvbdev = file->private_data;
 919         struct dvb_frontend *fe = dvbdev->priv;
 920         struct dvb_frontend_private *fepriv = fe->frontend_priv;
 921         int ret;
 922
 923         dprintk ("%s\n", __FUNCTION__);
 924
 925         if ((ret = dvb_generic_open (inode, file)) < 0)
 926                 return ret;
 927
 928         if ((file->f_flags & O_ACCMODE) != O_RDONLY) {
 929                 ret = dvb_frontend_start (fe);
 930                 if (ret)
 931                         dvb_generic_release (inode, file);
 932
 933                 /*  empty event queue */
 934                 fepriv->events.eventr = fepriv->events.eventw = 0;
 935         }
 936
 937         return ret;
 938 }
 939
 940 static int dvb_frontend_release(struct inode *inode, struct file *file)
 941 {
 942         struct dvb_device *dvbdev = file->private_data;
 943         struct dvb_frontend *fe = dvbdev->priv;
 944         struct dvb_frontend_private *fepriv = fe->frontend_priv;
 945
 946         dprintk ("%s\n", __FUNCTION__);
 947
 948         if ((file->f_flags & O_ACCMODE) != O_RDONLY)
 949                 fepriv->release_jiffies = jiffies;
 950
 951         return dvb_generic_release (inode, file);
 952 }
 953
 954 static struct file_operations dvb_frontend_fops = {
 955         .owner          = THIS_MODULE,
 956         .ioctl          = dvb_generic_ioctl,
 957         .poll           = dvb_frontend_poll,
 958         .open           = dvb_frontend_open,
 959         .release        = dvb_frontend_release
 960 };
 961
 962 int dvb_register_frontend(struct dvb_adapter* dvb,
 963                           struct dvb_frontend* fe)
 964 {
 965         struct dvb_frontend_private *fepriv;
 966         static const struct dvb_device dvbdev_template = {
 967                 .users = ~0,
 968                 .writers = 1,
 969                 .readers = (~0)-1,
 970                 .fops = &dvb_frontend_fops,
 971                 .kernel_ioctl = dvb_frontend_ioctl
 972         };
 973
 974         dprintk ("%s\n", __FUNCTION__);
 975
 976         if (down_interruptible (&frontend_mutex))
 977                 return -ERESTARTSYS;
 978
 979         fe->frontend_priv = kmalloc(sizeof(struct dvb_frontend_private), GFP_KERNEL);
 980         if (fe->frontend_priv == NULL) {
 981                 up(&frontend_mutex);
 982                 return -ENOMEM;
 983         }
 984         fepriv = fe->frontend_priv;
 985         memset(fe->frontend_priv, 0, sizeof(struct dvb_frontend_private));
 986
 987         init_MUTEX (&fepriv->sem);
 988         init_waitqueue_head (&fepriv->wait_queue);
 989         init_waitqueue_head (&fepriv->events.wait_queue);
 990         init_MUTEX (&fepriv->events.sem);
 991         fe->dvb = dvb;
 992         fepriv->inversion = INVERSION_OFF;
 993         fepriv->tone = SEC_TONE_OFF;
 994
 995         printk ("DVB: registering frontend %i (%s)...\n",
 996                 fe->dvb->num,
 997                 fe->ops->info.name);
 998
 999         dvb_register_device (fe->dvb, &fepriv->dvbdev, &dvbdev_template,
1000                              fe, DVB_DEVICE_FRONTEND);
1001
1002         up (&frontend_mutex);
1003         return 0;
1004 }
1005 EXPORT_SYMBOL(dvb_register_frontend);
1006
1007 int dvb_unregister_frontend(struct dvb_frontend* fe)
1008 {
1009         struct dvb_frontend_private *fepriv = fe->frontend_priv;
1010         dprintk ("%s\n", __FUNCTION__);
1011
1012         down (&frontend_mutex);
1013         dvb_unregister_device (fepriv->dvbdev);
1014         dvb_frontend_stop (fe);
1015         if (fe->ops->release)
1016                 fe->ops->release(fe);
1017         else
1018                 printk("dvb_frontend: Demodulator (%s) does not have a release callback!\n", fe->ops->info.name);
1019         /* fe is invalid now */
1020         kfree(fepriv);
1021         up (&frontend_mutex);
1022         return 0;
1023 }
1024 EXPORT_SYMBOL(dvb_unregister_frontend);