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