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 ppq */
 195 int snd_seq_timer_set_ppq(struct snd_seq_timer * tmr, int ppq)
 196 {
 197         unsigned long flags;
 198
 199         if (snd_BUG_ON(!tmr))
 200                 return -EINVAL;
 201         if (ppq <= 0)
 202                 return -EINVAL;
 203         spin_lock_irqsave(&tmr->lock, flags);
 204         if (tmr->running && (ppq != tmr->ppq)) {
 205                 /* refuse to change ppq on running timers */
 206                 /* because it will upset the song position (ticks) */
 207                 spin_unlock_irqrestore(&tmr->lock, flags);
 208                 pr_debug("ALSA: seq: cannot change ppq of a running timer\n");
 209                 return -EBUSY;
 210         }
 211
 212         tmr->ppq = ppq;
 213         snd_seq_timer_set_tick_resolution(tmr);
 214         spin_unlock_irqrestore(&tmr->lock, flags);
 215         return 0;
 216 }
 217
 218 /* set current tick position */
 219 int snd_seq_timer_set_position_tick(struct snd_seq_timer *tmr,
 220                                     snd_seq_tick_time_t position)
 221 {
 222         unsigned long flags;
 223
 224         if (snd_BUG_ON(!tmr))
 225                 return -EINVAL;
 226
 227         spin_lock_irqsave(&tmr->lock, flags);
 228         tmr->tick.cur_tick = position;
 229         tmr->tick.fraction = 0;
 230         spin_unlock_irqrestore(&tmr->lock, flags);
 231         return 0;
 232 }
 233
 234 /* set current real-time position */
 235 int snd_seq_timer_set_position_time(struct snd_seq_timer *tmr,
 236                                     snd_seq_real_time_t position)
 237 {
 238         unsigned long flags;
 239
 240         if (snd_BUG_ON(!tmr))
 241                 return -EINVAL;
 242
 243         snd_seq_sanity_real_time(&position);
 244         spin_lock_irqsave(&tmr->lock, flags);
 245         tmr->cur_time = position;
 246         spin_unlock_irqrestore(&tmr->lock, flags);
 247         return 0;
 248 }
 249
 250 /* set timer skew */
 251 int snd_seq_timer_set_skew(struct snd_seq_timer *tmr, unsigned int skew,
 252                            unsigned int base)
 253 {
 254         unsigned long flags;
 255
 256         if (snd_BUG_ON(!tmr))
 257                 return -EINVAL;
 258
 259         /* FIXME */
 260         if (base != SKEW_BASE) {
 261                 pr_debug("ALSA: seq: invalid skew base 0x%x\n", base);
 262                 return -EINVAL;
 263         }
 264         spin_lock_irqsave(&tmr->lock, flags);
 265         tmr->skew = skew;
 266         spin_unlock_irqrestore(&tmr->lock, flags);
 267         return 0;
 268 }
 269
 270 int snd_seq_timer_open(struct snd_seq_queue *q)
 271 {
 272         struct snd_timer_instance *t;
 273         struct snd_seq_timer *tmr;
 274         char str[32];
 275         int err;
 276
 277         tmr = q->timer;
 278         if (snd_BUG_ON(!tmr))
 279                 return -EINVAL;
 280         if (tmr->timeri)
 281                 return -EBUSY;
 282         sprintf(str, "sequencer queue %i", q->queue);
 283         if (tmr->type != SNDRV_SEQ_TIMER_ALSA)  /* standard ALSA timer */
 284                 return -EINVAL;
 285         if (tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_SLAVE)
 286                 tmr->alsa_id.dev_sclass = SNDRV_TIMER_SCLASS_SEQUENCER;
 287         err = snd_timer_open(&t, str, &tmr->alsa_id, q->queue);
 288         if (err < 0 && tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_SLAVE) {
 289                 if (tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_GLOBAL ||
 290                     tmr->alsa_id.device != SNDRV_TIMER_GLOBAL_SYSTEM) {
 291                         struct snd_timer_id tid;
 292                         memset(&tid, 0, sizeof(tid));
 293                         tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL;
 294                         tid.dev_sclass = SNDRV_TIMER_SCLASS_SEQUENCER;
 295                         tid.card = -1;
 296                         tid.device = SNDRV_TIMER_GLOBAL_SYSTEM;
 297                         err = snd_timer_open(&t, str, &tid, q->queue);
 298                 }
 299         }
 300         if (err < 0) {
 301                 pr_err("ALSA: seq fatal error: cannot create timer (%i)\n", err);
 302                 return err;
 303         }
 304         t->callback = snd_seq_timer_interrupt;
 305         t->callback_data = q;
 306         t->flags |= SNDRV_TIMER_IFLG_AUTO;
 307         spin_lock_irq(&tmr->lock);
 308         tmr->timeri = t;
 309         spin_unlock_irq(&tmr->lock);
 310         return 0;
 311 }
 312
 313 int snd_seq_timer_close(struct snd_seq_queue *q)
 314 {
 315         struct snd_seq_timer *tmr;
 316         struct snd_timer_instance *t;
 317
 318         tmr = q->timer;
 319         if (snd_BUG_ON(!tmr))
 320                 return -EINVAL;
 321         spin_lock_irq(&tmr->lock);
 322         t = tmr->timeri;
 323         tmr->timeri = NULL;
 324         spin_unlock_irq(&tmr->lock);
 325         if (t)
 326                 snd_timer_close(t);
 327         return 0;
 328 }
 329
 330 static int seq_timer_stop(struct snd_seq_timer *tmr)
 331 {
 332         if (! tmr->timeri)
 333                 return -EINVAL;
 334         if (!tmr->running)
 335                 return 0;
 336         tmr->running = 0;
 337         snd_timer_pause(tmr->timeri);
 338         return 0;
 339 }
 340
 341 int snd_seq_timer_stop(struct snd_seq_timer *tmr)
 342 {
 343         unsigned long flags;
 344         int err;
 345
 346         spin_lock_irqsave(&tmr->lock, flags);
 347         err = seq_timer_stop(tmr);
 348         spin_unlock_irqrestore(&tmr->lock, flags);
 349         return err;
 350 }
 351
 352 static int initialize_timer(struct snd_seq_timer *tmr)
 353 {
 354         struct snd_timer *t;
 355         unsigned long freq;
 356
 357         t = tmr->timeri->timer;
 358         if (snd_BUG_ON(!t))
 359                 return -EINVAL;
 360
 361         freq = tmr->preferred_resolution;
 362         if (!freq)
 363                 freq = DEFAULT_FREQUENCY;
 364         else if (freq < MIN_FREQUENCY)
 365                 freq = MIN_FREQUENCY;
 366         else if (freq > MAX_FREQUENCY)
 367                 freq = MAX_FREQUENCY;
 368
 369         tmr->ticks = 1;
 370         if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE)) {
 371                 unsigned long r = t->hw.resolution;
 372                 if (! r && t->hw.c_resolution)
 373                         r = t->hw.c_resolution(t);
 374                 if (r) {
 375                         tmr->ticks = (unsigned int)(1000000000uL / (r * freq));
 376                         if (! tmr->ticks)
 377                                 tmr->ticks = 1;
 378                 }
 379         }
 380         tmr->initialized = 1;
 381         return 0;
 382 }
 383
 384 static int seq_timer_start(struct snd_seq_timer *tmr)
 385 {
 386         if (! tmr->timeri)
 387                 return -EINVAL;
 388         if (tmr->running)
 389                 seq_timer_stop(tmr);
 390         seq_timer_reset(tmr);
 391         if (initialize_timer(tmr) < 0)
 392                 return -EINVAL;
 393         snd_timer_start(tmr->timeri, tmr->ticks);
 394         tmr->running = 1;
 395         ktime_get_ts64(&tmr->last_update);
 396         return 0;
 397 }
 398
 399 int snd_seq_timer_start(struct snd_seq_timer *tmr)
 400 {
 401         unsigned long flags;
 402         int err;
 403
 404         spin_lock_irqsave(&tmr->lock, flags);
 405         err = seq_timer_start(tmr);
 406         spin_unlock_irqrestore(&tmr->lock, flags);
 407         return err;
 408 }
 409
 410 static int seq_timer_continue(struct snd_seq_timer *tmr)
 411 {
 412         if (! tmr->timeri)
 413                 return -EINVAL;
 414         if (tmr->running)
 415                 return -EBUSY;
 416         if (! tmr->initialized) {
 417                 seq_timer_reset(tmr);
 418                 if (initialize_timer(tmr) < 0)
 419                         return -EINVAL;
 420         }
 421         snd_timer_start(tmr->timeri, tmr->ticks);
 422         tmr->running = 1;
 423         ktime_get_ts64(&tmr->last_update);
 424         return 0;
 425 }
 426
 427 int snd_seq_timer_continue(struct snd_seq_timer *tmr)
 428 {
 429         unsigned long flags;
 430         int err;
 431
 432         spin_lock_irqsave(&tmr->lock, flags);
 433         err = seq_timer_continue(tmr);
 434         spin_unlock_irqrestore(&tmr->lock, flags);
 435         return err;
 436 }
 437
 438 /* return current 'real' time. use timeofday() to get better granularity. */
 439 snd_seq_real_time_t snd_seq_timer_get_cur_time(struct snd_seq_timer *tmr)
 440 {
 441         snd_seq_real_time_t cur_time;
 442         unsigned long flags;
 443
 444         spin_lock_irqsave(&tmr->lock, flags);
 445         cur_time = tmr->cur_time;
 446         if (tmr->running) {
 447                 struct timespec64 tm;
 448
 449                 ktime_get_ts64(&tm);
 450                 tm = timespec64_sub(tm, tmr->last_update);
 451                 cur_time.tv_nsec += tm.tv_nsec;
 452                 cur_time.tv_sec += tm.tv_sec;
 453                 snd_seq_sanity_real_time(&cur_time);
 454         }
 455         spin_unlock_irqrestore(&tmr->lock, flags);
 456         return cur_time;
 457 }
 458
 459 /* TODO: use interpolation on tick queue (will only be useful for very
 460  high PPQ values) */
 461 snd_seq_tick_time_t snd_seq_timer_get_cur_tick(struct snd_seq_timer *tmr)
 462 {
 463         return tmr->tick.cur_tick;
 464 }
 465
 466
 467 #ifdef CONFIG_SND_PROC_FS
 468 /* exported to seq_info.c */
 469 void snd_seq_info_timer_read(struct snd_info_entry *entry,
 470                              struct snd_info_buffer *buffer)
 471 {
 472         int idx;
 473         struct snd_seq_queue *q;
 474         struct snd_seq_timer *tmr;
 475         struct snd_timer_instance *ti;
 476         unsigned long resolution;
 477
 478         for (idx = 0; idx < SNDRV_SEQ_MAX_QUEUES; idx++) {
 479                 q = queueptr(idx);
 480                 if (q == NULL)
 481                         continue;
 482                 if ((tmr = q->timer) == NULL ||
 483                     (ti = tmr->timeri) == NULL) {
 484                         queuefree(q);
 485                         continue;
 486                 }
 487                 snd_iprintf(buffer, "Timer for queue %i : %s\n", q->queue, ti->timer->name);
 488                 resolution = snd_timer_resolution(ti) * tmr->ticks;
 489                 snd_iprintf(buffer, "  Period time : %lu.%09lu\n", resolution / 1000000000, resolution % 1000000000);
 490                 snd_iprintf(buffer, "  Skew : %u / %u\n", tmr->skew, tmr->skew_base);
 491                 queuefree(q);
 492         }
 493 }
 494 #endif /* CONFIG_SND_PROC_FS */
 495