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)
  60                 return NULL;
  61         spin_lock_init(&tmr->lock);
  62
  63         /* reset setup to defaults */
  64         snd_seq_timer_defaults(tmr);
  65
  66         /* reset time */
  67         snd_seq_timer_reset(tmr);
  68
  69         return tmr;
  70 }
  71
  72 /* delete timer (destructor) */
  73 void snd_seq_timer_delete(struct snd_seq_timer **tmr)
  74 {
  75         struct snd_seq_timer *t = *tmr;
  76         *tmr = NULL;
  77
  78         if (t == NULL) {
  79                 pr_debug("ALSA: seq: snd_seq_timer_delete() called with NULL timer\n");
  80                 return;
  81         }
  82         t->running = 0;
  83
  84         /* reset time */
  85         snd_seq_timer_stop(t);
  86         snd_seq_timer_reset(t);
  87
  88         kfree(t);
  89 }
  90
  91 void snd_seq_timer_defaults(struct snd_seq_timer * tmr)
  92 {
  93         unsigned long flags;
  94
  95         spin_lock_irqsave(&tmr->lock, flags);
  96         /* setup defaults */
  97         tmr->ppq = 96;          /* 96 PPQ */
  98         tmr->tempo = 500000;    /* 120 BPM */
  99         snd_seq_timer_set_tick_resolution(tmr);
 100         tmr->running = 0;
 101
 102         tmr->type = SNDRV_SEQ_TIMER_ALSA;
 103         tmr->alsa_id.dev_class = seq_default_timer_class;
 104         tmr->alsa_id.dev_sclass = seq_default_timer_sclass;
 105         tmr->alsa_id.card = seq_default_timer_card;
 106         tmr->alsa_id.device = seq_default_timer_device;
 107         tmr->alsa_id.subdevice = seq_default_timer_subdevice;
 108         tmr->preferred_resolution = seq_default_timer_resolution;
 109
 110         tmr->skew = tmr->skew_base = SKEW_BASE;
 111         spin_unlock_irqrestore(&tmr->lock, flags);
 112 }
 113
 114 static void seq_timer_reset(struct snd_seq_timer *tmr)
 115 {
 116         /* reset time & songposition */
 117         tmr->cur_time.tv_sec = 0;
 118         tmr->cur_time.tv_nsec = 0;
 119
 120         tmr->tick.cur_tick = 0;
 121         tmr->tick.fraction = 0;
 122 }
 123
 124 void snd_seq_timer_reset(struct snd_seq_timer *tmr)
 125 {
 126         unsigned long flags;
 127
 128         spin_lock_irqsave(&tmr->lock, flags);
 129         seq_timer_reset(tmr);
 130         spin_unlock_irqrestore(&tmr->lock, flags);
 131 }
 132
 133
 134 /* called by timer interrupt routine. the period time since previous invocation is passed */
 135 static void snd_seq_timer_interrupt(struct snd_timer_instance *timeri,
 136                                     unsigned long resolution,
 137                                     unsigned long ticks)
 138 {
 139         unsigned long flags;
 140         struct snd_seq_queue *q = timeri->callback_data;
 141         struct snd_seq_timer *tmr;
 142
 143         if (q == NULL)
 144                 return;
 145         tmr = q->timer;
 146         if (tmr == NULL)
 147                 return;
 148         spin_lock_irqsave(&tmr->lock, flags);
 149         if (!tmr->running) {
 150                 spin_unlock_irqrestore(&tmr->lock, flags);
 151                 return;
 152         }
 153
 154         resolution *= ticks;
 155         if (tmr->skew != tmr->skew_base) {
 156                 /* FIXME: assuming skew_base = 0x10000 */
 157                 resolution = (resolution >> 16) * tmr->skew +
 158                         (((resolution & 0xffff) * tmr->skew) >> 16);
 159         }
 160
 161         /* update timer */
 162         snd_seq_inc_time_nsec(&tmr->cur_time, resolution);
 163
 164         /* calculate current tick */
 165         snd_seq_timer_update_tick(&tmr->tick, resolution);
 166
 167         /* register actual time of this timer update */
 168         ktime_get_ts64(&tmr->last_update);
 169
 170         spin_unlock_irqrestore(&tmr->lock, flags);
 171
 172         /* check queues and dispatch events */
 173         snd_seq_check_queue(q, 1, 0);
 174 }
 175
 176 /* set current tempo */
 177 int snd_seq_timer_set_tempo(struct snd_seq_timer * tmr, int tempo)
 178 {
 179         unsigned long flags;
 180
 181         if (snd_BUG_ON(!tmr))
 182                 return -EINVAL;
 183         if (tempo <= 0)
 184                 return -EINVAL;
 185         spin_lock_irqsave(&tmr->lock, flags);
 186         if ((unsigned int)tempo != tmr->tempo) {
 187                 tmr->tempo = tempo;
 188                 snd_seq_timer_set_tick_resolution(tmr);
 189         }
 190         spin_unlock_irqrestore(&tmr->lock, flags);
 191         return 0;
 192 }
 193
 194 /* set current tempo and ppq in a shot */
 195 int snd_seq_timer_set_tempo_ppq(struct snd_seq_timer *tmr, int tempo, int ppq)
 196 {
 197         int changed;
 198         unsigned long flags;
 199
 200         if (snd_BUG_ON(!tmr))
 201                 return -EINVAL;
 202         if (tempo <= 0 || ppq <= 0)
 203                 return -EINVAL;
 204         spin_lock_irqsave(&tmr->lock, flags);
 205         if (tmr->running && (ppq != tmr->ppq)) {
 206                 /* refuse to change ppq on running timers */
 207                 /* because it will upset the song position (ticks) */
 208                 spin_unlock_irqrestore(&tmr->lock, flags);
 209                 pr_debug("ALSA: seq: cannot change ppq of a running timer\n");
 210                 return -EBUSY;
 211         }
 212         changed = (tempo != tmr->tempo) || (ppq != tmr->ppq);
 213         tmr->tempo = tempo;
 214         tmr->ppq = ppq;
 215         if (changed)
 216                 snd_seq_timer_set_tick_resolution(tmr);
 217         spin_unlock_irqrestore(&tmr->lock, flags);
 218         return 0;
 219 }
 220
 221 /* set current tick position */
 222 int snd_seq_timer_set_position_tick(struct snd_seq_timer *tmr,
 223                                     snd_seq_tick_time_t position)
 224 {
 225         unsigned long flags;
 226
 227         if (snd_BUG_ON(!tmr))
 228                 return -EINVAL;
 229
 230         spin_lock_irqsave(&tmr->lock, flags);
 231         tmr->tick.cur_tick = position;
 232         tmr->tick.fraction = 0;
 233         spin_unlock_irqrestore(&tmr->lock, flags);
 234         return 0;
 235 }
 236
 237 /* set current real-time position */
 238 int snd_seq_timer_set_position_time(struct snd_seq_timer *tmr,
 239                                     snd_seq_real_time_t position)
 240 {
 241         unsigned long flags;
 242
 243         if (snd_BUG_ON(!tmr))
 244                 return -EINVAL;
 245
 246         snd_seq_sanity_real_time(&position);
 247         spin_lock_irqsave(&tmr->lock, flags);
 248         tmr->cur_time = position;
 249         spin_unlock_irqrestore(&tmr->lock, flags);
 250         return 0;
 251 }
 252
 253 /* set timer skew */
 254 int snd_seq_timer_set_skew(struct snd_seq_timer *tmr, unsigned int skew,
 255                            unsigned int base)
 256 {
 257         unsigned long flags;
 258
 259         if (snd_BUG_ON(!tmr))
 260                 return -EINVAL;
 261
 262         /* FIXME */
 263         if (base != SKEW_BASE) {
 264                 pr_debug("ALSA: seq: invalid skew base 0x%x\n", base);
 265                 return -EINVAL;
 266         }
 267         spin_lock_irqsave(&tmr->lock, flags);
 268         tmr->skew = skew;
 269         spin_unlock_irqrestore(&tmr->lock, flags);
 270         return 0;
 271 }
 272
 273 int snd_seq_timer_open(struct snd_seq_queue *q)
 274 {
 275         struct snd_timer_instance *t;
 276         struct snd_seq_timer *tmr;
 277         char str[32];
 278         int err;
 279
 280         tmr = q->timer;
 281         if (snd_BUG_ON(!tmr))
 282                 return -EINVAL;
 283         if (tmr->timeri)
 284                 return -EBUSY;
 285         sprintf(str, "sequencer queue %i", q->queue);
 286         if (tmr->type != SNDRV_SEQ_TIMER_ALSA)  /* standard ALSA timer */
 287                 return -EINVAL;
 288         if (tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_SLAVE)
 289                 tmr->alsa_id.dev_sclass = SNDRV_TIMER_SCLASS_SEQUENCER;
 290         err = snd_timer_open(&t, str, &tmr->alsa_id, q->queue);
 291         if (err < 0 && tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_SLAVE) {
 292                 if (tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_GLOBAL ||
 293                     tmr->alsa_id.device != SNDRV_TIMER_GLOBAL_SYSTEM) {
 294                         struct snd_timer_id tid;
 295                         memset(&tid, 0, sizeof(tid));
 296                         tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL;
 297                         tid.dev_sclass = SNDRV_TIMER_SCLASS_SEQUENCER;
 298                         tid.card = -1;
 299                         tid.device = SNDRV_TIMER_GLOBAL_SYSTEM;
 300                         err = snd_timer_open(&t, str, &tid, q->queue);
 301                 }
 302         }
 303         if (err < 0) {
 304                 pr_err("ALSA: seq fatal error: cannot create timer (%i)\n", err);
 305                 return err;
 306         }
 307         t->callback = snd_seq_timer_interrupt;
 308         t->callback_data = q;
 309         t->flags |= SNDRV_TIMER_IFLG_AUTO;
 310         spin_lock_irq(&tmr->lock);
 311         tmr->timeri = t;
 312         spin_unlock_irq(&tmr->lock);
 313         return 0;
 314 }
 315
 316 int snd_seq_timer_close(struct snd_seq_queue *q)
 317 {
 318         struct snd_seq_timer *tmr;
 319         struct snd_timer_instance *t;
 320
 321         tmr = q->timer;
 322         if (snd_BUG_ON(!tmr))
 323                 return -EINVAL;
 324         spin_lock_irq(&tmr->lock);
 325         t = tmr->timeri;
 326         tmr->timeri = NULL;
 327         spin_unlock_irq(&tmr->lock);
 328         if (t)
 329                 snd_timer_close(t);
 330         return 0;
 331 }
 332
 333 static int seq_timer_stop(struct snd_seq_timer *tmr)
 334 {
 335         if (! tmr->timeri)
 336                 return -EINVAL;
 337         if (!tmr->running)
 338                 return 0;
 339         tmr->running = 0;
 340         snd_timer_pause(tmr->timeri);
 341         return 0;
 342 }
 343
 344 int snd_seq_timer_stop(struct snd_seq_timer *tmr)
 345 {
 346         unsigned long flags;
 347         int err;
 348
 349         spin_lock_irqsave(&tmr->lock, flags);
 350         err = seq_timer_stop(tmr);
 351         spin_unlock_irqrestore(&tmr->lock, flags);
 352         return err;
 353 }
 354
 355 static int initialize_timer(struct snd_seq_timer *tmr)
 356 {
 357         struct snd_timer *t;
 358         unsigned long freq;
 359
 360         t = tmr->timeri->timer;
 361         if (!t)
 362                 return -EINVAL;
 363
 364         freq = tmr->preferred_resolution;
 365         if (!freq)
 366                 freq = DEFAULT_FREQUENCY;
 367         else if (freq < MIN_FREQUENCY)
 368                 freq = MIN_FREQUENCY;
 369         else if (freq > MAX_FREQUENCY)
 370                 freq = MAX_FREQUENCY;
 371
 372         tmr->ticks = 1;
 373         if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE)) {
 374                 unsigned long r = t->hw.resolution;
 375                 if (! r && t->hw.c_resolution)
 376                         r = t->hw.c_resolution(t);
 377                 if (r) {
 378                         tmr->ticks = (unsigned int)(1000000000uL / (r * freq));
 379                         if (! tmr->ticks)
 380                                 tmr->ticks = 1;
 381                 }
 382         }
 383         tmr->initialized = 1;
 384         return 0;
 385 }
 386
 387 static int seq_timer_start(struct snd_seq_timer *tmr)
 388 {
 389         if (! tmr->timeri)
 390                 return -EINVAL;
 391         if (tmr->running)
 392                 seq_timer_stop(tmr);
 393         seq_timer_reset(tmr);
 394         if (initialize_timer(tmr) < 0)
 395                 return -EINVAL;
 396         snd_timer_start(tmr->timeri, tmr->ticks);
 397         tmr->running = 1;
 398         ktime_get_ts64(&tmr->last_update);
 399         return 0;
 400 }
 401
 402 int snd_seq_timer_start(struct snd_seq_timer *tmr)
 403 {
 404         unsigned long flags;
 405         int err;
 406
 407         spin_lock_irqsave(&tmr->lock, flags);
 408         err = seq_timer_start(tmr);
 409         spin_unlock_irqrestore(&tmr->lock, flags);
 410         return err;
 411 }
 412
 413 static int seq_timer_continue(struct snd_seq_timer *tmr)
 414 {
 415         if (! tmr->timeri)
 416                 return -EINVAL;
 417         if (tmr->running)
 418                 return -EBUSY;
 419         if (! tmr->initialized) {
 420                 seq_timer_reset(tmr);
 421                 if (initialize_timer(tmr) < 0)
 422                         return -EINVAL;
 423         }
 424         snd_timer_start(tmr->timeri, tmr->ticks);
 425         tmr->running = 1;
 426         ktime_get_ts64(&tmr->last_update);
 427         return 0;
 428 }
 429
 430 int snd_seq_timer_continue(struct snd_seq_timer *tmr)
 431 {
 432         unsigned long flags;
 433         int err;
 434
 435         spin_lock_irqsave(&tmr->lock, flags);
 436         err = seq_timer_continue(tmr);
 437         spin_unlock_irqrestore(&tmr->lock, flags);
 438         return err;
 439 }
 440
 441 /* return current 'real' time. use timeofday() to get better granularity. */
 442 snd_seq_real_time_t snd_seq_timer_get_cur_time(struct snd_seq_timer *tmr)
 443 {
 444         snd_seq_real_time_t cur_time;
 445         unsigned long flags;
 446
 447         spin_lock_irqsave(&tmr->lock, flags);
 448         cur_time = tmr->cur_time;
 449         if (tmr->running) {
 450                 struct timespec64 tm;
 451
 452                 ktime_get_ts64(&tm);
 453                 tm = timespec64_sub(tm, tmr->last_update);
 454                 cur_time.tv_nsec += tm.tv_nsec;
 455                 cur_time.tv_sec += tm.tv_sec;
 456                 snd_seq_sanity_real_time(&cur_time);
 457         }
 458         spin_unlock_irqrestore(&tmr->lock, flags);
 459         return cur_time;
 460 }
 461
 462 /* TODO: use interpolation on tick queue (will only be useful for very
 463  high PPQ values) */
 464 snd_seq_tick_time_t snd_seq_timer_get_cur_tick(struct snd_seq_timer *tmr)
 465 {
 466         return tmr->tick.cur_tick;
 467 }
 468
 469
 470 #ifdef CONFIG_SND_PROC_FS
 471 /* exported to seq_info.c */
 472 void snd_seq_info_timer_read(struct snd_info_entry *entry,
 473                              struct snd_info_buffer *buffer)
 474 {
 475         int idx;
 476         struct snd_seq_queue *q;
 477         struct snd_seq_timer *tmr;
 478         struct snd_timer_instance *ti;
 479         unsigned long resolution;
 480
 481         for (idx = 0; idx < SNDRV_SEQ_MAX_QUEUES; idx++) {
 482                 q = queueptr(idx);
 483                 if (q == NULL)
 484                         continue;
 485                 if ((tmr = q->timer) == NULL ||
 486                     (ti = tmr->timeri) == NULL) {
 487                         queuefree(q);
 488                         continue;
 489                 }
 490                 snd_iprintf(buffer, "Timer for queue %i : %s\n", q->queue, ti->timer->name);
 491                 resolution = snd_timer_resolution(ti) * tmr->ticks;
 492                 snd_iprintf(buffer, "  Period time : %lu.%09lu\n", resolution / 1000000000, resolution % 1000000000);
 493                 snd_iprintf(buffer, "  Skew : %u / %u\n", tmr->skew, tmr->skew_base);
 494                 queuefree(q);
 495         }
 496 }
 497 #endif /* CONFIG_SND_PROC_FS */
 498