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         /* thread/frontend values */
  96         struct dvb_device *dvbdev;
  97         struct dvb_frontend_parameters parameters;
  98         struct dvb_fe_events events;
  99         struct semaphore sem;
 100         struct list_head list_head;
 101         wait_queue_head_t wait_queue;
 102         pid_t thread_pid;
 103         unsigned long release_jiffies;
 104         unsigned int exit;
 105         unsigned int wakeup;
 106         fe_status_t status;
 107         unsigned long tune_mode_flags;
 108         unsigned int delay;
 109
 110         /* swzigzag values */
 111         unsigned int state;
 112         unsigned int bending;
 113         int lnb_drift;
 114         unsigned int inversion;
 115         unsigned int auto_step;
 116         unsigned int auto_sub_step;
 117         unsigned int started_auto_step;
 118         unsigned int min_delay;
 119         unsigned int max_drift;
 120         unsigned int step_size;
 121         int quality;
 122         unsigned int check_wrapped;
 123 };
 124
 125
 126 static void dvb_frontend_add_event(struct dvb_frontend *fe, fe_status_t status)
 127 {
 128         struct dvb_frontend_private *fepriv = fe->frontend_priv;
 129         struct dvb_fe_events *events = &fepriv->events;
 130         struct dvb_frontend_event *e;
 131         int wp;
 132
 133         dprintk ("%s\n", __FUNCTION__);
 134
 135         if (down_interruptible (&events->sem))
 136                 return;
 137
 138         wp = (events->eventw + 1) % MAX_EVENT;
 139
 140         if (wp == events->eventr) {
 141                 events->overflow = 1;
 142                 events->eventr = (events->eventr + 1) % MAX_EVENT;
 143         }
 144
 145         e = &events->events[events->eventw];
 146
 147         memcpy (&e->parameters, &fepriv->parameters,
 148                 sizeof (struct dvb_frontend_parameters));
 149
 150         if (status & FE_HAS_LOCK)
 151                 if (fe->ops->get_frontend)
 152                         fe->ops->get_frontend(fe, &e->parameters);
 153
 154         events->eventw = wp;
 155
 156         up (&events->sem);
 157
 158         e->status = status;
 159
 160         wake_up_interruptible (&events->wait_queue);
 161 }
 162
 163 static int dvb_frontend_get_event(struct dvb_frontend *fe,
 164                             struct dvb_frontend_event *event, int flags)
 165 {
 166         struct dvb_frontend_private *fepriv = fe->frontend_priv;
 167         struct dvb_fe_events *events = &fepriv->events;
 168
 169         dprintk ("%s\n", __FUNCTION__);
 170
 171         if (events->overflow) {
 172                 events->overflow = 0;
 173                 return -EOVERFLOW;
 174         }
 175
 176         if (events->eventw == events->eventr) {
 177                 int ret;
 178
 179                 if (flags & O_NONBLOCK)
 180                         return -EWOULDBLOCK;
 181
 182                 up(&fepriv->sem);
 183
 184                 ret = wait_event_interruptible (events->wait_queue,
 185                                                 events->eventw != events->eventr);
 186
 187                 if (down_interruptible (&fepriv->sem))
 188                         return -ERESTARTSYS;
 189
 190                 if (ret < 0)
 191                         return ret;
 192         }
 193
 194         if (down_interruptible (&events->sem))
 195                 return -ERESTARTSYS;
 196
 197         memcpy (event, &events->events[events->eventr],
 198                 sizeof(struct dvb_frontend_event));
 199
 200         events->eventr = (events->eventr + 1) % MAX_EVENT;
 201
 202         up (&events->sem);
 203
 204         return 0;
 205 }
 206
 207 static void dvb_frontend_init(struct dvb_frontend *fe)
 208 {
 209         dprintk ("DVB: initialising frontend %i (%s)...\n",
 210                  fe->dvb->num,
 211                  fe->ops->info.name);
 212
 213         if (fe->ops->init)
 214                 fe->ops->init(fe);
 215 }
 216
 217 static void dvb_frontend_swzigzag_update_delay(struct dvb_frontend_private *fepriv, int locked)
 218 {
 219         int q2;
 220
 221         dprintk ("%s\n", __FUNCTION__);
 222
 223         if (locked)
 224                 (fepriv->quality) = (fepriv->quality * 220 + 36*256) / 256;
 225         else
 226                 (fepriv->quality) = (fepriv->quality * 220 + 0) / 256;
 227
 228         q2 = fepriv->quality - 128;
 229         q2 *= q2;
 230
 231         fepriv->delay = fepriv->min_delay + q2 * HZ / (128*128);
 232 }
 233
 234 /**
 235  * Performs automatic twiddling of frontend parameters.
 236  *
 237  * @param fe The frontend concerned.
 238  * @param check_wrapped Checks if an iteration has completed. DO NOT SET ON THE FIRST ATTEMPT
 239  * @returns Number of complete iterations that have been performed.
 240  */
 241 static int dvb_frontend_swzigzag_autotune(struct dvb_frontend *fe, int check_wrapped)
 242 {
 243         int autoinversion;
 244         int ready = 0;
 245         struct dvb_frontend_private *fepriv = fe->frontend_priv;
 246         int original_inversion = fepriv->parameters.inversion;
 247         u32 original_frequency = fepriv->parameters.frequency;
 248
 249         /* are we using autoinversion? */
 250         autoinversion = ((!(fe->ops->info.caps & FE_CAN_INVERSION_AUTO)) &&
 251                          (fepriv->parameters.inversion == INVERSION_AUTO));
 252
 253         /* setup parameters correctly */
 254         while(!ready) {
 255                 /* calculate the lnb_drift */
 256                 fepriv->lnb_drift = fepriv->auto_step * fepriv->step_size;
 257
 258                 /* wrap the auto_step if we've exceeded the maximum drift */
 259                 if (fepriv->lnb_drift > fepriv->max_drift) {
 260                         fepriv->auto_step = 0;
 261                         fepriv->auto_sub_step = 0;
 262                         fepriv->lnb_drift = 0;
 263                 }
 264
 265                 /* perform inversion and +/- zigzag */
 266                 switch(fepriv->auto_sub_step) {
 267                 case 0:
 268                         /* try with the current inversion and current drift setting */
 269                         ready = 1;
 270                         break;
 271
 272                 case 1:
 273                         if (!autoinversion) break;
 274
 275                         fepriv->inversion = (fepriv->inversion == INVERSION_OFF) ? INVERSION_ON : INVERSION_OFF;
 276                         ready = 1;
 277                         break;
 278
 279                 case 2:
 280                         if (fepriv->lnb_drift == 0) break;
 281
 282                         fepriv->lnb_drift = -fepriv->lnb_drift;
 283                         ready = 1;
 284                         break;
 285
 286                 case 3:
 287                         if (fepriv->lnb_drift == 0) break;
 288                         if (!autoinversion) break;
 289
 290                         fepriv->inversion = (fepriv->inversion == INVERSION_OFF) ? INVERSION_ON : INVERSION_OFF;
 291                         fepriv->lnb_drift = -fepriv->lnb_drift;
 292                         ready = 1;
 293                         break;
 294
 295                 default:
 296                         fepriv->auto_step++;
 297                         fepriv->auto_sub_step = -1; /* it'll be incremented to 0 in a moment */
 298                         break;
 299                 }
 300
 301                 if (!ready) fepriv->auto_sub_step++;
 302         }
 303
 304         /* if this attempt would hit where we started, indicate a complete
 305          * iteration has occurred */
 306         if ((fepriv->auto_step == fepriv->started_auto_step) &&
 307             (fepriv->auto_sub_step == 0) && check_wrapped) {
 308                 return 1;
 309         }
 310
 311         dprintk("%s: drift:%i inversion:%i auto_step:%i "
 312                 "auto_sub_step:%i started_auto_step:%i\n",
 313                 __FUNCTION__, fepriv->lnb_drift, fepriv->inversion,
 314                 fepriv->auto_step, fepriv->auto_sub_step, fepriv->started_auto_step);
 315
 316         /* set the frontend itself */
 317         fepriv->parameters.frequency += fepriv->lnb_drift;
 318         if (autoinversion)
 319                 fepriv->parameters.inversion = fepriv->inversion;
 320         if (fe->ops->set_frontend)
 321                 fe->ops->set_frontend(fe, &fepriv->parameters);
 322
 323         fepriv->parameters.frequency = original_frequency;
 324         fepriv->parameters.inversion = original_inversion;
 325
 326         fepriv->auto_sub_step++;
 327         return 0;
 328 }
 329
 330 static void dvb_frontend_swzigzag(struct dvb_frontend *fe)
 331 {
 332         fe_status_t s;
 333         struct dvb_frontend_private *fepriv = fe->frontend_priv;
 334
 335         /* if we've got no parameters, just keep idling */
 336         if (fepriv->state & FESTATE_IDLE) {
 337                 fepriv->delay = 3*HZ;
 338                 fepriv->quality = 0;
 339                 return;
 340         }
 341
 342         /* in SCAN mode, we just set the frontend when asked and leave it alone */
 343         if (fepriv->tune_mode_flags & FE_TUNE_MODE_ONESHOT) {
 344                 if (fepriv->state & FESTATE_RETUNE) {
 345                         if (fe->ops->set_frontend)
 346                                 fe->ops->set_frontend(fe, &fepriv->parameters);
 347                         fepriv->state = FESTATE_TUNED;
 348                 }
 349                 fepriv->delay = 3*HZ;
 350                 fepriv->quality = 0;
 351                 return;
 352         }
 353
 354         /* get the frontend status */
 355         if (fepriv->state & FESTATE_RETUNE) {
 356                 s = 0;
 357         } else {
 358                 if (fe->ops->read_status)
 359                         fe->ops->read_status(fe, &s);
 360                 if (s != fepriv->status) {
 361                         dvb_frontend_add_event(fe, s);
 362                         fepriv->status = s;
 363                 }
 364         }
 365
 366         /* if we're not tuned, and we have a lock, move to the TUNED state */
 367         if ((fepriv->state & FESTATE_WAITFORLOCK) && (s & FE_HAS_LOCK)) {
 368                 dvb_frontend_swzigzag_update_delay(fepriv, s & FE_HAS_LOCK);
 369                 fepriv->state = FESTATE_TUNED;
 370
 371                 /* if we're tuned, then we have determined the correct inversion */
 372                 if ((!(fe->ops->info.caps & FE_CAN_INVERSION_AUTO)) &&
 373                     (fepriv->parameters.inversion == INVERSION_AUTO)) {
 374                         fepriv->parameters.inversion = fepriv->inversion;
 375                 }
 376                 return;
 377         }
 378
 379         /* if we are tuned already, check we're still locked */
 380         if (fepriv->state & FESTATE_TUNED) {
 381                 dvb_frontend_swzigzag_update_delay(fepriv, s & FE_HAS_LOCK);
 382
 383                 /* we're tuned, and the lock is still good... */
 384                 if (s & FE_HAS_LOCK) {
 385                         return;
 386                 } else { /* if we _WERE_ tuned, but now don't have a lock */
 387                         fepriv->state = FESTATE_ZIGZAG_FAST;
 388                         fepriv->started_auto_step = fepriv->auto_step;
 389                         fepriv->check_wrapped = 0;
 390                 }
 391         }
 392
 393         /* don't actually do anything if we're in the LOSTLOCK state,
 394          * the frontend is set to FE_CAN_RECOVER, and the max_drift is 0 */
 395         if ((fepriv->state & FESTATE_LOSTLOCK) &&
 396             (fe->ops->info.caps & FE_CAN_RECOVER) && (fepriv->max_drift == 0)) {
 397                 dvb_frontend_swzigzag_update_delay(fepriv, s & FE_HAS_LOCK);
 398                 return;
 399         }
 400
 401         /* don't do anything if we're in the DISEQC state, since this
 402          * might be someone with a motorized dish controlled by DISEQC.
 403          * If its actually a re-tune, there will be a SET_FRONTEND soon enough. */
 404         if (fepriv->state & FESTATE_DISEQC) {
 405                 dvb_frontend_swzigzag_update_delay(fepriv, s & FE_HAS_LOCK);
 406                 return;
 407         }
 408
 409         /* if we're in the RETUNE state, set everything up for a brand
 410          * new scan, keeping the current inversion setting, as the next
 411          * tune is _very_ likely to require the same */
 412         if (fepriv->state & FESTATE_RETUNE) {
 413                 fepriv->lnb_drift = 0;
 414                 fepriv->auto_step = 0;
 415                 fepriv->auto_sub_step = 0;
 416                 fepriv->started_auto_step = 0;
 417                 fepriv->check_wrapped = 0;
 418         }
 419
 420         /* fast zigzag. */
 421         if ((fepriv->state & FESTATE_SEARCHING_FAST) || (fepriv->state & FESTATE_RETUNE)) {
 422                 fepriv->delay = fepriv->min_delay;
 423
 424                 /* peform a tune */
 425                 if (dvb_frontend_swzigzag_autotune(fe, fepriv->check_wrapped)) {
 426                         /* OK, if we've run out of trials at the fast speed.
 427                          * Drop back to slow for the _next_ attempt */
 428                         fepriv->state = FESTATE_SEARCHING_SLOW;
 429                         fepriv->started_auto_step = fepriv->auto_step;
 430                         return;
 431                 }
 432                 fepriv->check_wrapped = 1;
 433
 434                 /* if we've just retuned, enter the ZIGZAG_FAST state.
 435                  * This ensures we cannot return from an
 436                  * FE_SET_FRONTEND ioctl before the first frontend tune
 437                  * occurs */
 438                 if (fepriv->state & FESTATE_RETUNE) {
 439                         fepriv->state = FESTATE_TUNING_FAST;
 440                 }
 441         }
 442
 443         /* slow zigzag */
 444         if (fepriv->state & FESTATE_SEARCHING_SLOW) {
 445                 dvb_frontend_swzigzag_update_delay(fepriv, s & FE_HAS_LOCK);
 446
 447                 /* Note: don't bother checking for wrapping; we stay in this
 448                  * state until we get a lock */
 449                 dvb_frontend_swzigzag_autotune(fe, 0);
 450         }
 451 }
 452
 453 static int dvb_frontend_is_exiting(struct dvb_frontend *fe)
 454 {
 455         struct dvb_frontend_private *fepriv = fe->frontend_priv;
 456
 457         if (fepriv->exit)
 458                 return 1;
 459
 460         if (fepriv->dvbdev->writers == 1)
 461                 if (time_after(jiffies, fepriv->release_jiffies +
 462                                   dvb_shutdown_timeout * HZ))
 463                         return 1;
 464
 465         return 0;
 466 }
 467
 468 static int dvb_frontend_should_wakeup(struct dvb_frontend *fe)
 469 {
 470         struct dvb_frontend_private *fepriv = fe->frontend_priv;
 471
 472         if (fepriv->wakeup) {
 473                 fepriv->wakeup = 0;
 474                 return 1;
 475         }
 476         return dvb_frontend_is_exiting(fe);
 477 }
 478
 479 static void dvb_frontend_wakeup(struct dvb_frontend *fe)
 480 {
 481         struct dvb_frontend_private *fepriv = fe->frontend_priv;
 482
 483         fepriv->wakeup = 1;
 484         wake_up_interruptible(&fepriv->wait_queue);
 485 }
 486
 487 static int dvb_frontend_thread(void *data)
 488 {
 489         struct dvb_frontend *fe = data;
 490         struct dvb_frontend_private *fepriv = fe->frontend_priv;
 491         unsigned long timeout;
 492         char name [15];
 493         fe_status_t s;
 494         struct dvb_frontend_parameters *params;
 495
 496         dprintk("%s\n", __FUNCTION__);
 497
 498         snprintf (name, sizeof(name), "kdvb-fe-%i", fe->dvb->num);
 499
 500         lock_kernel();
 501         daemonize(name);
 502         sigfillset(&current->blocked);
 503         unlock_kernel();
 504
 505         fepriv->check_wrapped = 0;
 506         fepriv->quality = 0;
 507         fepriv->delay = 3*HZ;
 508         fepriv->status = 0;
 509         dvb_frontend_init(fe);
 510         fepriv->wakeup = 0;
 511
 512         while (1) {
 513                 up(&fepriv->sem);           /* is locked when we enter the thread... */
 514
 515                 timeout = wait_event_interruptible_timeout(fepriv->wait_queue,
 516                                                            dvb_frontend_should_wakeup(fe),
 517                                                            fepriv->delay);
 518                 if (0 != dvb_frontend_is_exiting(fe)) {
 519                         /* got signal or quitting */
 520                         break;
 521                 }
 522
 523                 try_to_freeze();
 524
 525                 if (down_interruptible(&fepriv->sem))
 526                         break;
 527
 528                 /* do an iteration of the tuning loop */
 529                 if (fe->ops->tune) {
 530                         /* have we been asked to retune? */
 531                         params = NULL;
 532                         if (fepriv->state & FESTATE_RETUNE) {
 533                                 params = &fepriv->parameters;
 534                                 fepriv->state = FESTATE_TUNED;
 535                         }
 536
 537                         fe->ops->tune(fe, params, fepriv->tune_mode_flags, &fepriv->delay, &s);
 538                         if (s != fepriv->status) {
 539                                 dvb_frontend_add_event(fe, s);
 540                                 fepriv->status = s;
 541                         }
 542                 } else {
 543                         dvb_frontend_swzigzag(fe);
 544                 }
 545         }
 546
 547         if (dvb_shutdown_timeout) {
 548                 if (dvb_powerdown_on_sleep)
 549                         if (fe->ops->set_voltage)
 550                                 fe->ops->set_voltage(fe, SEC_VOLTAGE_OFF);
 551                 if (fe->ops->sleep)
 552                         fe->ops->sleep(fe);
 553         }
 554
 555         fepriv->thread_pid = 0;
 556         mb();
 557
 558         dvb_frontend_wakeup(fe);
 559         return 0;
 560 }
 561
 562 static void dvb_frontend_stop(struct dvb_frontend *fe)
 563 {
 564         unsigned long ret;
 565         struct dvb_frontend_private *fepriv = fe->frontend_priv;
 566
 567         dprintk ("%s\n", __FUNCTION__);
 568
 569         fepriv->exit = 1;
 570         mb();
 571
 572         if (!fepriv->thread_pid)
 573                 return;
 574
 575         /* check if the thread is really alive */
 576         if (kill_proc(fepriv->thread_pid, 0, 1) == -ESRCH) {
 577                 printk("dvb_frontend_stop: thread PID %d already died\n",
 578                                 fepriv->thread_pid);
 579                 /* make sure the mutex was not held by the thread */
 580                 init_MUTEX (&fepriv->sem);
 581                 return;
 582         }
 583
 584         /* wake up the frontend thread, so it notices that fe->exit == 1 */
 585         dvb_frontend_wakeup(fe);
 586
 587         /* wait until the frontend thread has exited */
 588         ret = wait_event_interruptible(fepriv->wait_queue,0 == fepriv->thread_pid);
 589         if (-ERESTARTSYS != ret) {
 590                 fepriv->state = FESTATE_IDLE;
 591                 return;
 592         }
 593         fepriv->state = FESTATE_IDLE;
 594
 595         /* paranoia check in case a signal arrived */
 596         if (fepriv->thread_pid)
 597                 printk("dvb_frontend_stop: warning: thread PID %d won't exit\n",
 598                                 fepriv->thread_pid);
 599 }
 600
 601 s32 timeval_usec_diff(struct timeval lasttime, struct timeval curtime)
 602 {
 603         return ((curtime.tv_usec < lasttime.tv_usec) ?
 604                 1000000 - lasttime.tv_usec + curtime.tv_usec :
 605                 curtime.tv_usec - lasttime.tv_usec);
 606 }
 607 EXPORT_SYMBOL(timeval_usec_diff);
 608
 609 static inline void timeval_usec_add(struct timeval *curtime, u32 add_usec)
 610 {
 611         curtime->tv_usec += add_usec;
 612         if (curtime->tv_usec >= 1000000) {
 613                 curtime->tv_usec -= 1000000;
 614                 curtime->tv_sec++;
 615         }
 616 }
 617
 618 /*
 619  * Sleep until gettimeofday() > waketime + add_usec
 620  * This needs to be as precise as possible, but as the delay is
 621  * usually between 2ms and 32ms, it is done using a scheduled msleep
 622  * followed by usleep (normally a busy-wait loop) for the remainder
 623  */
 624 void dvb_frontend_sleep_until(struct timeval *waketime, u32 add_usec)
 625 {
 626         struct timeval lasttime;
 627         s32 delta, newdelta;
 628
 629         timeval_usec_add(waketime, add_usec);
 630
 631         do_gettimeofday(&lasttime);
 632         delta = timeval_usec_diff(lasttime, *waketime);
 633         if (delta > 2500) {
 634                 msleep((delta - 1500) / 1000);
 635                 do_gettimeofday(&lasttime);
 636                 newdelta = timeval_usec_diff(lasttime, *waketime);
 637                 delta = (newdelta > delta) ? 0 : newdelta;
 638         }
 639         if (delta > 0)
 640                 udelay(delta);
 641 }
 642 EXPORT_SYMBOL(dvb_frontend_sleep_until);
 643
 644 static int dvb_frontend_start(struct dvb_frontend *fe)
 645 {
 646         int ret;
 647         struct dvb_frontend_private *fepriv = fe->frontend_priv;
 648
 649         dprintk ("%s\n", __FUNCTION__);
 650
 651         if (fepriv->thread_pid) {
 652                 if (!fepriv->exit)
 653                         return 0;
 654                 else
 655                         dvb_frontend_stop (fe);
 656         }
 657
 658         if (signal_pending(current))
 659                 return -EINTR;
 660         if (down_interruptible (&fepriv->sem))
 661                 return -EINTR;
 662
 663         fepriv->state = FESTATE_IDLE;
 664         fepriv->exit = 0;
 665         fepriv->thread_pid = 0;
 666         mb();
 667
 668         ret = kernel_thread (dvb_frontend_thread, fe, 0);
 669
 670         if (ret < 0) {
 671                 printk("dvb_frontend_start: failed to start kernel_thread (%d)\n", ret);
 672                 up(&fepriv->sem);
 673                 return ret;
 674         }
 675         fepriv->thread_pid = ret;
 676
 677         return 0;
 678 }
 679
 680 static int dvb_frontend_ioctl(struct inode *inode, struct file *file,
 681                         unsigned int cmd, void *parg)
 682 {
 683         struct dvb_device *dvbdev = file->private_data;
 684         struct dvb_frontend *fe = dvbdev->priv;
 685         struct dvb_frontend_private *fepriv = fe->frontend_priv;
 686         int err = -EOPNOTSUPP;
 687
 688         dprintk ("%s\n", __FUNCTION__);
 689
 690         if (!fe || fepriv->exit)
 691                 return -ENODEV;
 692
 693         if ((file->f_flags & O_ACCMODE) == O_RDONLY &&
 694             (_IOC_DIR(cmd) != _IOC_READ || cmd == FE_GET_EVENT ||
 695              cmd == FE_DISEQC_RECV_SLAVE_REPLY))
 696                 return -EPERM;
 697
 698         if (down_interruptible (&fepriv->sem))
 699                 return -ERESTARTSYS;
 700
 701         switch (cmd) {
 702         case FE_GET_INFO: {
 703                 struct dvb_frontend_info* info = parg;
 704                 memcpy(info, &fe->ops->info, sizeof(struct dvb_frontend_info));
 705
 706                 /* Force the CAN_INVERSION_AUTO bit on. If the frontend doesn't
 707                  * do it, it is done for it. */
 708                 info->caps |= FE_CAN_INVERSION_AUTO;
 709                 err = 0;
 710                 break;
 711         }
 712
 713         case FE_READ_STATUS: {
 714                 fe_status_t* status = parg;
 715
 716                 /* if retune was requested but hasn't occured yet, prevent
 717                  * that user get signal state from previous tuning */
 718                 if(fepriv->state == FESTATE_RETUNE) {
 719                         err=0;
 720                         *status = 0;
 721                         break;
 722                 }
 723
 724                 if (fe->ops->read_status)
 725                         err = fe->ops->read_status(fe, status);
 726                 break;
 727         }
 728         case FE_READ_BER:
 729                 if (fe->ops->read_ber)
 730                         err = fe->ops->read_ber(fe, (__u32*) parg);
 731                 break;
 732
 733         case FE_READ_SIGNAL_STRENGTH:
 734                 if (fe->ops->read_signal_strength)
 735                         err = fe->ops->read_signal_strength(fe, (__u16*) parg);
 736                 break;
 737
 738         case FE_READ_SNR:
 739                 if (fe->ops->read_snr)
 740                         err = fe->ops->read_snr(fe, (__u16*) parg);
 741                 break;
 742
 743         case FE_READ_UNCORRECTED_BLOCKS:
 744                 if (fe->ops->read_ucblocks)
 745                         err = fe->ops->read_ucblocks(fe, (__u32*) parg);
 746                 break;
 747
 748
 749         case FE_DISEQC_RESET_OVERLOAD:
 750                 if (fe->ops->diseqc_reset_overload) {
 751                         err = fe->ops->diseqc_reset_overload(fe);
 752                         fepriv->state = FESTATE_DISEQC;
 753                         fepriv->status = 0;
 754                 }
 755                 break;
 756
 757         case FE_DISEQC_SEND_MASTER_CMD:
 758                 if (fe->ops->diseqc_send_master_cmd) {
 759                         err = fe->ops->diseqc_send_master_cmd(fe, (struct dvb_diseqc_master_cmd*) parg);
 760                         fepriv->state = FESTATE_DISEQC;
 761                         fepriv->status = 0;
 762                 }
 763                 break;
 764
 765         case FE_DISEQC_SEND_BURST:
 766                 if (fe->ops->diseqc_send_burst) {
 767                         err = fe->ops->diseqc_send_burst(fe, (fe_sec_mini_cmd_t) parg);
 768                         fepriv->state = FESTATE_DISEQC;
 769                         fepriv->status = 0;
 770                 }
 771                 break;
 772
 773         case FE_SET_TONE:
 774                 if (fe->ops->set_tone) {
 775                         err = fe->ops->set_tone(fe, (fe_sec_tone_mode_t) parg);
 776                         fepriv->state = FESTATE_DISEQC;
 777                         fepriv->status = 0;
 778                 }
 779                 break;
 780
 781         case FE_SET_VOLTAGE:
 782                 if (fe->ops->set_voltage) {
 783                         err = fe->ops->set_voltage(fe, (fe_sec_voltage_t) parg);
 784                         fepriv->state = FESTATE_DISEQC;
 785                         fepriv->status = 0;
 786                 }
 787                 break;
 788
 789         case FE_DISHNETWORK_SEND_LEGACY_CMD:
 790                 if (fe->ops->dishnetwork_send_legacy_command) {
 791                         err = fe->ops->dishnetwork_send_legacy_command(fe, (unsigned long) parg);
 792                         fepriv->state = FESTATE_DISEQC;
 793                         fepriv->status = 0;
 794                 } else if (fe->ops->set_voltage) {
 795                         /*
 796                          * NOTE: This is a fallback condition.  Some frontends
 797                          * (stv0299 for instance) take longer than 8msec to
 798                          * respond to a set_voltage command.  Those switches
 799                          * need custom routines to switch properly.  For all
 800                          * other frontends, the following shoule work ok.
 801                          * Dish network legacy switches (as used by Dish500)
 802                          * are controlled by sending 9-bit command words
 803                          * spaced 8msec apart.
 804                          * the actual command word is switch/port dependant
 805                          * so it is up to the userspace application to send
 806                          * the right command.
 807                          * The command must always start with a '0' after
 808                          * initialization, so parg is 8 bits and does not
 809                          * include the initialization or start bit
 810                          */
 811                         unsigned long cmd = ((unsigned long) parg) << 1;
 812                         struct timeval nexttime;
 813                         struct timeval tv[10];
 814                         int i;
 815                         u8 last = 1;
 816                         if (dvb_frontend_debug)
 817                                 printk("%s switch command: 0x%04lx\n", __FUNCTION__, cmd);
 818                         do_gettimeofday(&nexttime);
 819                         if (dvb_frontend_debug)
 820                                 memcpy(&tv[0], &nexttime, sizeof(struct timeval));
 821                         /* before sending a command, initialize by sending
 822                          * a 32ms 18V to the switch
 823                          */
 824                         fe->ops->set_voltage(fe, SEC_VOLTAGE_18);
 825                         dvb_frontend_sleep_until(&nexttime, 32000);
 826
 827                         for (i = 0; i < 9; i++) {
 828                                 if (dvb_frontend_debug)
 829                                         do_gettimeofday(&tv[i + 1]);
 830                                 if ((cmd & 0x01) != last) {
 831                                         /* set voltage to (last ? 13V : 18V) */
 832                                         fe->ops->set_voltage(fe, (last) ? SEC_VOLTAGE_13 : SEC_VOLTAGE_18);
 833                                         last = (last) ? 0 : 1;
 834                                 }
 835                                 cmd = cmd >> 1;
 836                                 if (i != 8)
 837                                         dvb_frontend_sleep_until(&nexttime, 8000);
 838                         }
 839                         if (dvb_frontend_debug) {
 840                                 printk("%s(%d): switch delay (should be 32k followed by all 8k\n",
 841                                         __FUNCTION__, fe->dvb->num);
 842                                 for (i = 1; i < 10; i++)
 843                                         printk("%d: %d\n", i, timeval_usec_diff(tv[i-1] , tv[i]));
 844                         }
 845                         err = 0;
 846                         fepriv->state = FESTATE_DISEQC;
 847                         fepriv->status = 0;
 848                 }
 849                 break;
 850
 851         case FE_DISEQC_RECV_SLAVE_REPLY:
 852                 if (fe->ops->diseqc_recv_slave_reply)
 853                         err = fe->ops->diseqc_recv_slave_reply(fe, (struct dvb_diseqc_slave_reply*) parg);
 854                 break;
 855
 856         case FE_ENABLE_HIGH_LNB_VOLTAGE:
 857                 if (fe->ops->enable_high_lnb_voltage)
 858                         err = fe->ops->enable_high_lnb_voltage(fe, (long) parg);
 859                 break;
 860
 861         case FE_SET_FRONTEND: {
 862                 struct dvb_frontend_tune_settings fetunesettings;
 863
 864                 memcpy (&fepriv->parameters, parg,
 865                         sizeof (struct dvb_frontend_parameters));
 866
 867                 memset(&fetunesettings, 0, sizeof(struct dvb_frontend_tune_settings));
 868                 memcpy(&fetunesettings.parameters, parg,
 869                        sizeof (struct dvb_frontend_parameters));
 870
 871                 /* force auto frequency inversion if requested */
 872                 if (dvb_force_auto_inversion) {
 873                         fepriv->parameters.inversion = INVERSION_AUTO;
 874                         fetunesettings.parameters.inversion = INVERSION_AUTO;
 875                 }
 876                 if (fe->ops->info.type == FE_OFDM) {
 877                         /* without hierachical coding code_rate_LP is irrelevant,
 878                          * so we tolerate the otherwise invalid FEC_NONE setting */
 879                         if (fepriv->parameters.u.ofdm.hierarchy_information == HIERARCHY_NONE &&
 880                             fepriv->parameters.u.ofdm.code_rate_LP == FEC_NONE)
 881                                 fepriv->parameters.u.ofdm.code_rate_LP = FEC_AUTO;
 882                 }
 883
 884                 /* get frontend-specific tuning settings */
 885                 if (fe->ops->get_tune_settings && (fe->ops->get_tune_settings(fe, &fetunesettings) == 0)) {
 886                         fepriv->min_delay = (fetunesettings.min_delay_ms * HZ) / 1000;
 887                         fepriv->max_drift = fetunesettings.max_drift;
 888                         fepriv->step_size = fetunesettings.step_size;
 889                 } else {
 890                         /* default values */
 891                         switch(fe->ops->info.type) {
 892                         case FE_QPSK:
 893                                 fepriv->min_delay = HZ/20;
 894                                 fepriv->step_size = fepriv->parameters.u.qpsk.symbol_rate / 16000;
 895                                 fepriv->max_drift = fepriv->parameters.u.qpsk.symbol_rate / 2000;
 896                                 break;
 897
 898                         case FE_QAM:
 899                                 fepriv->min_delay = HZ/20;
 900                                 fepriv->step_size = 0; /* no zigzag */
 901                                 fepriv->max_drift = 0;
 902                                 break;
 903
 904                         case FE_OFDM:
 905                                 fepriv->min_delay = HZ/20;
 906                                 fepriv->step_size = fe->ops->info.frequency_stepsize * 2;
 907                                 fepriv->max_drift = (fe->ops->info.frequency_stepsize * 2) + 1;
 908                                 break;
 909                         case FE_ATSC:
 910                                 printk("dvb-core: FE_ATSC not handled yet.\n");
 911                                 break;
 912                         }
 913                 }
 914                 if (dvb_override_tune_delay > 0)
 915                         fepriv->min_delay = (dvb_override_tune_delay * HZ) / 1000;
 916
 917                 fepriv->state = FESTATE_RETUNE;
 918                 dvb_frontend_wakeup(fe);
 919                 dvb_frontend_add_event(fe, 0);
 920                 fepriv->status = 0;
 921                 err = 0;
 922                 break;
 923         }
 924
 925         case FE_GET_EVENT:
 926                 err = dvb_frontend_get_event (fe, parg, file->f_flags);
 927                 break;
 928
 929         case FE_GET_FRONTEND:
 930                 if (fe->ops->get_frontend) {
 931                         memcpy (parg, &fepriv->parameters, sizeof (struct dvb_frontend_parameters));
 932                         err = fe->ops->get_frontend(fe, (struct dvb_frontend_parameters*) parg);
 933                 }
 934                 break;
 935
 936         case FE_SET_FRONTEND_TUNE_MODE:
 937                 fepriv->tune_mode_flags = (unsigned long) parg;
 938                 break;
 939         };
 940
 941         up (&fepriv->sem);
 942         return err;
 943 }
 944
 945 static unsigned int dvb_frontend_poll(struct file *file, struct poll_table_struct *wait)
 946 {
 947         struct dvb_device *dvbdev = file->private_data;
 948         struct dvb_frontend *fe = dvbdev->priv;
 949         struct dvb_frontend_private *fepriv = fe->frontend_priv;
 950
 951         dprintk ("%s\n", __FUNCTION__);
 952
 953         poll_wait (file, &fepriv->events.wait_queue, wait);
 954
 955         if (fepriv->events.eventw != fepriv->events.eventr)
 956                 return (POLLIN | POLLRDNORM | POLLPRI);
 957
 958         return 0;
 959 }
 960
 961 static int dvb_frontend_open(struct inode *inode, struct file *file)
 962 {
 963         struct dvb_device *dvbdev = file->private_data;
 964         struct dvb_frontend *fe = dvbdev->priv;
 965         struct dvb_frontend_private *fepriv = fe->frontend_priv;
 966         int ret;
 967
 968         dprintk ("%s\n", __FUNCTION__);
 969
 970         if ((ret = dvb_generic_open (inode, file)) < 0)
 971                 return ret;
 972
 973         if ((file->f_flags & O_ACCMODE) != O_RDONLY) {
 974                 ret = dvb_frontend_start (fe);
 975                 if (ret)
 976                         dvb_generic_release (inode, file);
 977
 978                 /*  empty event queue */
 979                 fepriv->events.eventr = fepriv->events.eventw = 0;
 980
 981                 /* normal tune mode when opened R/W */
 982                 fepriv->tune_mode_flags &= ~FE_TUNE_MODE_ONESHOT;
 983         }
 984
 985         return ret;
 986 }
 987
 988 static int dvb_frontend_release(struct inode *inode, struct file *file)
 989 {
 990         struct dvb_device *dvbdev = file->private_data;
 991         struct dvb_frontend *fe = dvbdev->priv;
 992         struct dvb_frontend_private *fepriv = fe->frontend_priv;
 993
 994         dprintk ("%s\n", __FUNCTION__);
 995
 996         if ((file->f_flags & O_ACCMODE) != O_RDONLY)
 997                 fepriv->release_jiffies = jiffies;
 998
 999         return dvb_generic_release (inode, file);
1000 }
1001
1002 static struct file_operations dvb_frontend_fops = {
1003         .owner          = THIS_MODULE,
1004         .ioctl          = dvb_generic_ioctl,
1005         .poll           = dvb_frontend_poll,
1006         .open           = dvb_frontend_open,
1007         .release        = dvb_frontend_release
1008 };
1009
1010 int dvb_register_frontend(struct dvb_adapter* dvb,
1011                           struct dvb_frontend* fe)
1012 {
1013         struct dvb_frontend_private *fepriv;
1014         static const struct dvb_device dvbdev_template = {
1015                 .users = ~0,
1016                 .writers = 1,
1017                 .readers = (~0)-1,
1018                 .fops = &dvb_frontend_fops,
1019                 .kernel_ioctl = dvb_frontend_ioctl
1020         };
1021
1022         dprintk ("%s\n", __FUNCTION__);
1023
1024         if (down_interruptible (&frontend_mutex))
1025                 return -ERESTARTSYS;
1026
1027         fe->frontend_priv = kzalloc(sizeof(struct dvb_frontend_private), GFP_KERNEL);
1028         if (fe->frontend_priv == NULL) {
1029                 up(&frontend_mutex);
1030                 return -ENOMEM;
1031         }
1032         fepriv = fe->frontend_priv;
1033
1034         init_MUTEX (&fepriv->sem);
1035         init_waitqueue_head (&fepriv->wait_queue);
1036         init_waitqueue_head (&fepriv->events.wait_queue);
1037         init_MUTEX (&fepriv->events.sem);
1038         fe->dvb = dvb;
1039         fepriv->inversion = INVERSION_OFF;
1040
1041         printk ("DVB: registering frontend %i (%s)...\n",
1042                 fe->dvb->num,
1043                 fe->ops->info.name);
1044
1045         dvb_register_device (fe->dvb, &fepriv->dvbdev, &dvbdev_template,
1046                              fe, DVB_DEVICE_FRONTEND);
1047
1048         up (&frontend_mutex);
1049         return 0;
1050 }
1051 EXPORT_SYMBOL(dvb_register_frontend);
1052
1053 int dvb_unregister_frontend(struct dvb_frontend* fe)
1054 {
1055         struct dvb_frontend_private *fepriv = fe->frontend_priv;
1056         dprintk ("%s\n", __FUNCTION__);
1057
1058         down (&frontend_mutex);
1059         dvb_unregister_device (fepriv->dvbdev);
1060         dvb_frontend_stop (fe);
1061         if (fe->ops->release)
1062                 fe->ops->release(fe);
1063         else
1064                 printk("dvb_frontend: Demodulator (%s) does not have a release callback!\n", fe->ops->info.name);
1065         /* fe is invalid now */
1066         kfree(fepriv);
1067         up (&frontend_mutex);
1068         return 0;
1069 }
1070 EXPORT_SYMBOL(dvb_unregister_frontend);