sound/core/seq/seq_timer.c

   1 /*
   2  *   ALSA sequencer Timer
   3  *   Copyright (c) 1998-1999 by Frank van de Pol <fvdpol@coil.demon.nl>
   4  *                              Jaroslav Kysela <perex@perex.cz>
   5  *
   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., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  20  *
  21  */
  22
  23 #include <sound/core.h>
  24 #include <linux/slab.h>
  25 #include "seq_timer.h"
  26 #include "seq_queue.h"
  27 #include "seq_info.h"
  28
  29 /* allowed sequencer timer frequencies, in Hz */
  30 #define MIN_FREQUENCY           10
  31 #define MAX_FREQUENCY           6250
  32 #define DEFAULT_FREQUENCY       1000
  33
  34 #define SKEW_BASE       0x10000 /* 16bit shift */
  35
  36 static void snd_seq_timer_set_tick_resolution(struct snd_seq_timer *tmr)
  37 {
  38         if (tmr->tempo < 1000000)
  39                 tmr->tick.resolution = (tmr->tempo * 1000) / tmr->ppq;
  40         else {
  41                 /* might overflow.. */
  42                 unsigned int s;
  43                 s = tmr->tempo % tmr->ppq;
  44                 s = (s * 1000) / tmr->ppq;
  45                 tmr->tick.resolution = (tmr->tempo / tmr->ppq) * 1000;
  46                 tmr->tick.resolution += s;
  47         }
  48         if (tmr->tick.resolution <= 0)
  49                 tmr->tick.resolution = 1;
  50         snd_seq_timer_update_tick(&tmr->tick, 0);
  51 }
  52
  53 /* create new timer (constructor) */
  54 struct snd_seq_timer *snd_seq_timer_new(void)
  55 {
  56         struct snd_seq_timer *tmr;
  57
  58         tmr = kzalloc(sizeof(*tmr), GFP_KERNEL);
  59         if (tmr == NULL) {
  60                 pr_debug("ALSA: seq: malloc failed for snd_seq_timer_new() \n");
  61                 return NULL;
  62         }
  63         spin_lock_init(&tmr->lock);
  64
  65         /* reset setup to defaults */
  66         snd_seq_timer_defaults(tmr);
  67
  68         /* reset time */
  69         snd_seq_timer_reset(tmr);
  70
  71         return tmr;
  72 }
  73
  74 /* delete timer (destructor) */
  75 void snd_seq_timer_delete(struct snd_seq_timer **tmr)
  76 {
  77         struct snd_seq_timer *t = *tmr;
  78         *tmr = NULL;
  79
  80         if (t == NULL) {
  81                 pr_debug("ALSA: seq: snd_seq_timer_delete() called with NULL timer\n");
  82                 return;
  83         }
  84         t->running = 0;
  85
  86         /* reset time */
  87         snd_seq_timer_stop(t);
  88         snd_seq_timer_reset(t);
  89
  90         kfree(t);
  91 }
  92
  93 void snd_seq_timer_defaults(struct snd_seq_timer * tmr)
  94 {
  95         /* setup defaults */
  96         tmr->ppq = 96;          /* 96 PPQ */
  97         tmr->tempo = 500000;    /* 120 BPM */
  98         snd_seq_timer_set_tick_resolution(tmr);
  99         tmr->running = 0;
 100
 101         tmr->type = SNDRV_SEQ_TIMER_ALSA;
 102         tmr->alsa_id.dev_class = seq_default_timer_class;
 103         tmr->alsa_id.dev_sclass = seq_default_timer_sclass;
 104         tmr->alsa_id.card = seq_default_timer_card;
 105         tmr->alsa_id.device = seq_default_timer_device;
 106         tmr->alsa_id.subdevice = seq_default_timer_subdevice;
 107         tmr->preferred_resolution = seq_default_timer_resolution;
 108
 109         tmr->skew = tmr->skew_base = SKEW_BASE;
 110 }
 111
 112 void snd_seq_timer_reset(struct snd_seq_timer * tmr)
 113 {
 114         unsigned long flags;
 115
 116         spin_lock_irqsave(&tmr->lock, flags);
 117
 118         /* reset time & songposition */
 119         tmr->cur_time.tv_sec = 0;
 120         tmr->cur_time.tv_nsec = 0;
 121
 122         tmr->tick.cur_tick = 0;
 123         tmr->tick.fraction = 0;
 124
 125         spin_unlock_irqrestore(&tmr->lock, flags);
 126 }
 127
 128
 129 /* called by timer interrupt routine. the period time since previous invocation is passed */
 130 static void snd_seq_timer_interrupt(struct snd_timer_instance *timeri,
 131                                     unsigned long resolution,
 132                                     unsigned long ticks)
 133 {
 134         unsigned long flags;
 135         struct snd_seq_queue *q = timeri->callback_data;
 136         struct snd_seq_timer *tmr;
 137
 138         if (q == NULL)
 139                 return;
 140         tmr = q->timer;
 141         if (tmr == NULL)
 142                 return;
 143         if (!tmr->running)
 144                 return;
 145
 146         resolution *= ticks;
 147         if (tmr->skew != tmr->skew_base) {
 148                 /* FIXME: assuming skew_base = 0x10000 */
 149                 resolution = (resolution >> 16) * tmr->skew +
 150                         (((resolution & 0xffff) * tmr->skew) >> 16);
 151         }
 152
 153         spin_lock_irqsave(&tmr->lock, flags);
 154
 155         /* update timer */
 156         snd_seq_inc_time_nsec(&tmr->cur_time, resolution);
 157
 158         /* calculate current tick */
 159         snd_seq_timer_update_tick(&tmr->tick, resolution);
 160
 161         /* register actual time of this timer update */
 162         do_gettimeofday(&tmr->last_update);
 163
 164         spin_unlock_irqrestore(&tmr->lock, flags);
 165
 166         /* check queues and dispatch events */
 167         snd_seq_check_queue(q, 1, 0);
 168 }
 169
 170 /* set current tempo */
 171 int snd_seq_timer_set_tempo(struct snd_seq_timer * tmr, int tempo)
 172 {
 173         unsigned long flags;
 174
 175         if (snd_BUG_ON(!tmr))
 176                 return -EINVAL;
 177         if (tempo <= 0)
 178                 return -EINVAL;
 179         spin_lock_irqsave(&tmr->lock, flags);
 180         if ((unsigned int)tempo != tmr->tempo) {
 181                 tmr->tempo = tempo;
 182                 snd_seq_timer_set_tick_resolution(tmr);
 183         }
 184         spin_unlock_irqrestore(&tmr->lock, flags);
 185         return 0;
 186 }
 187
 188 /* set current ppq */
 189 int snd_seq_timer_set_ppq(struct snd_seq_timer * tmr, int ppq)
 190 {
 191         unsigned long flags;
 192
 193         if (snd_BUG_ON(!tmr))
 194                 return -EINVAL;
 195         if (ppq <= 0)
 196                 return -EINVAL;
 197         spin_lock_irqsave(&tmr->lock, flags);
 198         if (tmr->running && (ppq != tmr->ppq)) {
 199                 /* refuse to change ppq on running timers */
 200                 /* because it will upset the song position (ticks) */
 201                 spin_unlock_irqrestore(&tmr->lock, flags);
 202                 pr_debug("ALSA: seq: cannot change ppq of a running timer\n");
 203                 return -EBUSY;
 204         }
 205
 206         tmr->ppq = ppq;
 207         snd_seq_timer_set_tick_resolution(tmr);
 208         spin_unlock_irqrestore(&tmr->lock, flags);
 209         return 0;
 210 }
 211
 212 /* set current tick position */
 213 int snd_seq_timer_set_position_tick(struct snd_seq_timer *tmr,
 214                                     snd_seq_tick_time_t position)
 215 {
 216         unsigned long flags;
 217
 218         if (snd_BUG_ON(!tmr))
 219                 return -EINVAL;
 220
 221         spin_lock_irqsave(&tmr->lock, flags);
 222         tmr->tick.cur_tick = position;
 223         tmr->tick.fraction = 0;
 224         spin_unlock_irqrestore(&tmr->lock, flags);
 225         return 0;
 226 }
 227
 228 /* set current real-time position */
 229 int snd_seq_timer_set_position_time(struct snd_seq_timer *tmr,
 230                                     snd_seq_real_time_t position)
 231 {
 232         unsigned long flags;
 233
 234         if (snd_BUG_ON(!tmr))
 235                 return -EINVAL;
 236
 237         snd_seq_sanity_real_time(&position);
 238         spin_lock_irqsave(&tmr->lock, flags);
 239         tmr->cur_time = position;
 240         spin_unlock_irqrestore(&tmr->lock, flags);
 241         return 0;
 242 }
 243
 244 /* set timer skew */
 245 int snd_seq_timer_set_skew(struct snd_seq_timer *tmr, unsigned int skew,
 246                            unsigned int base)
 247 {
 248         unsigned long flags;
 249
 250         if (snd_BUG_ON(!tmr))
 251                 return -EINVAL;
 252
 253         /* FIXME */
 254         if (base != SKEW_BASE) {
 255                 pr_debug("ALSA: seq: invalid skew base 0x%x\n", base);
 256                 return -EINVAL;
 257         }
 258         spin_lock_irqsave(&tmr->lock, flags);
 259         tmr->skew = skew;
 260         spin_unlock_irqrestore(&tmr->lock, flags);
 261         return 0;
 262 }
 263
 264 int snd_seq_timer_open(struct snd_seq_queue *q)
 265 {
 266         struct snd_timer_instance *t;
 267         struct snd_seq_timer *tmr;
 268         char str[32];
 269         int err;
 270
 271         tmr = q->timer;
 272         if (snd_BUG_ON(!tmr))
 273                 return -EINVAL;
 274         if (tmr->timeri)
 275                 return -EBUSY;
 276         sprintf(str, "sequencer queue %i", q->queue);
 277         if (tmr->type != SNDRV_SEQ_TIMER_ALSA)  /* standard ALSA timer */
 278                 return -EINVAL;
 279         if (tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_SLAVE)
 280                 tmr->alsa_id.dev_sclass = SNDRV_TIMER_SCLASS_SEQUENCER;
 281         err = snd_timer_open(&t, str, &tmr->alsa_id, q->queue);
 282         if (err < 0 && tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_SLAVE) {
 283                 if (tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_GLOBAL ||
 284                     tmr->alsa_id.device != SNDRV_TIMER_GLOBAL_SYSTEM) {
 285                         struct snd_timer_id tid;
 286                         memset(&tid, 0, sizeof(tid));
 287                         tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL;
 288                         tid.dev_sclass = SNDRV_TIMER_SCLASS_SEQUENCER;
 289                         tid.card = -1;
 290                         tid.device = SNDRV_TIMER_GLOBAL_SYSTEM;
 291                         err = snd_timer_open(&t, str, &tid, q->queue);
 292                 }
 293         }
 294         if (err < 0) {
 295                 pr_err("ALSA: seq fatal error: cannot create timer (%i)\n", err);
 296                 return err;
 297         }
 298         t->callback = snd_seq_timer_interrupt;
 299         t->callback_data = q;
 300         t->flags |= SNDRV_TIMER_IFLG_AUTO;
 301         tmr->timeri = t;
 302         return 0;
 303 }
 304
 305 int snd_seq_timer_close(struct snd_seq_queue *q)
 306 {
 307         struct snd_seq_timer *tmr;
 308
 309         tmr = q->timer;
 310         if (snd_BUG_ON(!tmr))
 311                 return -EINVAL;
 312         if (tmr->timeri) {
 313                 snd_timer_stop(tmr->timeri);
 314                 snd_timer_close(tmr->timeri);
 315                 tmr->timeri = NULL;
 316         }
 317         return 0;
 318 }
 319
 320 int snd_seq_timer_stop(struct snd_seq_timer * tmr)
 321 {
 322         if (! tmr->timeri)
 323                 return -EINVAL;
 324         if (!tmr->running)
 325                 return 0;
 326         tmr->running = 0;
 327         snd_timer_pause(tmr->timeri);
 328         return 0;
 329 }
 330
 331 static int initialize_timer(struct snd_seq_timer *tmr)
 332 {
 333         struct snd_timer *t;
 334         unsigned long freq;
 335
 336         t = tmr->timeri->timer;
 337         if (snd_BUG_ON(!t))
 338                 return -EINVAL;
 339
 340         freq = tmr->preferred_resolution;
 341         if (!freq)
 342                 freq = DEFAULT_FREQUENCY;
 343         else if (freq < MIN_FREQUENCY)
 344                 freq = MIN_FREQUENCY;
 345         else if (freq > MAX_FREQUENCY)
 346                 freq = MAX_FREQUENCY;
 347
 348         tmr->ticks = 1;
 349         if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE)) {
 350                 unsigned long r = t->hw.resolution;
 351                 if (! r && t->hw.c_resolution)
 352                         r = t->hw.c_resolution(t);
 353                 if (r) {
 354                         tmr->ticks = (unsigned int)(1000000000uL / (r * freq));
 355                         if (! tmr->ticks)
 356                                 tmr->ticks = 1;
 357                 }
 358         }
 359         tmr->initialized = 1;
 360         return 0;
 361 }
 362
 363 int snd_seq_timer_start(struct snd_seq_timer * tmr)
 364 {
 365         if (! tmr->timeri)
 366                 return -EINVAL;
 367         if (tmr->running)
 368                 snd_seq_timer_stop(tmr);
 369         snd_seq_timer_reset(tmr);
 370         if (initialize_timer(tmr) < 0)
 371                 return -EINVAL;
 372         snd_timer_start(tmr->timeri, tmr->ticks);
 373         tmr->running = 1;
 374         do_gettimeofday(&tmr->last_update);
 375         return 0;
 376 }
 377
 378 int snd_seq_timer_continue(struct snd_seq_timer * tmr)
 379 {
 380         if (! tmr->timeri)
 381                 return -EINVAL;
 382         if (tmr->running)
 383                 return -EBUSY;
 384         if (! tmr->initialized) {
 385                 snd_seq_timer_reset(tmr);
 386                 if (initialize_timer(tmr) < 0)
 387                         return -EINVAL;
 388         }
 389         snd_timer_start(tmr->timeri, tmr->ticks);
 390         tmr->running = 1;
 391         do_gettimeofday(&tmr->last_update);
 392         return 0;
 393 }
 394
 395 /* return current 'real' time. use timeofday() to get better granularity. */
 396 snd_seq_real_time_t snd_seq_timer_get_cur_time(struct snd_seq_timer *tmr)
 397 {
 398         snd_seq_real_time_t cur_time;
 399
 400         cur_time = tmr->cur_time;
 401         if (tmr->running) {
 402                 struct timeval tm;
 403                 int usec;
 404                 do_gettimeofday(&tm);
 405                 usec = (int)(tm.tv_usec - tmr->last_update.tv_usec);
 406                 if (usec < 0) {
 407                         cur_time.tv_nsec += (1000000 + usec) * 1000;
 408                         cur_time.tv_sec += tm.tv_sec - tmr->last_update.tv_sec - 1;
 409                 } else {
 410                         cur_time.tv_nsec += usec * 1000;
 411                         cur_time.tv_sec += tm.tv_sec - tmr->last_update.tv_sec;
 412                 }
 413                 snd_seq_sanity_real_time(&cur_time);
 414         }
 415
 416         return cur_time;
 417 }
 418
 419 /* TODO: use interpolation on tick queue (will only be useful for very
 420  high PPQ values) */
 421 snd_seq_tick_time_t snd_seq_timer_get_cur_tick(struct snd_seq_timer *tmr)
 422 {
 423         return tmr->tick.cur_tick;
 424 }
 425
 426
 427 #ifdef CONFIG_PROC_FS
 428 /* exported to seq_info.c */
 429 void snd_seq_info_timer_read(struct snd_info_entry *entry,
 430                              struct snd_info_buffer *buffer)
 431 {
 432         int idx;
 433         struct snd_seq_queue *q;
 434         struct snd_seq_timer *tmr;
 435         struct snd_timer_instance *ti;
 436         unsigned long resolution;
 437
 438         for (idx = 0; idx < SNDRV_SEQ_MAX_QUEUES; idx++) {
 439                 q = queueptr(idx);
 440                 if (q == NULL)
 441                         continue;
 442                 if ((tmr = q->timer) == NULL ||
 443                     (ti = tmr->timeri) == NULL) {
 444                         queuefree(q);
 445                         continue;
 446                 }
 447                 snd_iprintf(buffer, "Timer for queue %i : %s\n", q->queue, ti->timer->name);
 448                 resolution = snd_timer_resolution(ti) * tmr->ticks;
 449                 snd_iprintf(buffer, "  Period time : %lu.%09lu\n", resolution / 1000000000, resolution % 1000000000);
 450                 snd_iprintf(buffer, "  Skew : %u / %u\n", tmr->skew, tmr->skew_base);
 451                 queuefree(q);
 452         }
 453 }
 454 #endif /* CONFIG_PROC_FS */
 455