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_tick *tick,
  37                                               int tempo, int ppq)
  38 {
  39         if (tempo < 1000000)
  40                 tick->resolution = (tempo * 1000) / ppq;
  41         else {
  42                 /* might overflow.. */
  43                 unsigned int s;
  44                 s = tempo % ppq;
  45                 s = (s * 1000) / ppq;
  46                 tick->resolution = (tempo / ppq) * 1000;
  47                 tick->resolution += s;
  48         }
  49         if (tick->resolution <= 0)
  50                 tick->resolution = 1;
  51         snd_seq_timer_update_tick(tick, 0);
  52 }
  53
  54 /* create new timer (constructor) */
  55 struct snd_seq_timer *snd_seq_timer_new(void)
  56 {
  57         struct snd_seq_timer *tmr;
  58
  59         tmr = kzalloc(sizeof(*tmr), GFP_KERNEL);
  60         if (tmr == NULL) {
  61                 snd_printd("malloc failed for snd_seq_timer_new() \n");
  62                 return NULL;
  63         }
  64         spin_lock_init(&tmr->lock);
  65
  66         /* reset setup to defaults */
  67         snd_seq_timer_defaults(tmr);
  68
  69         /* reset time */
  70         snd_seq_timer_reset(tmr);
  71
  72         return tmr;
  73 }
  74
  75 /* delete timer (destructor) */
  76 void snd_seq_timer_delete(struct snd_seq_timer **tmr)
  77 {
  78         struct snd_seq_timer *t = *tmr;
  79         *tmr = NULL;
  80
  81         if (t == NULL) {
  82                 snd_printd("oops: snd_seq_timer_delete() called with NULL timer\n");
  83                 return;
  84         }
  85         t->running = 0;
  86
  87         /* reset time */
  88         snd_seq_timer_stop(t);
  89         snd_seq_timer_reset(t);
  90
  91         kfree(t);
  92 }
  93
  94 void snd_seq_timer_defaults(struct snd_seq_timer * tmr)
  95 {
  96         /* setup defaults */
  97         tmr->ppq = 96;          /* 96 PPQ */
  98         tmr->tempo = 500000;    /* 120 BPM */
  99         snd_seq_timer_set_tick_resolution(&tmr->tick, tmr->tempo, tmr->ppq);
 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 }
 112
 113 void snd_seq_timer_reset(struct snd_seq_timer * tmr)
 114 {
 115         unsigned long flags;
 116
 117         spin_lock_irqsave(&tmr->lock, flags);
 118
 119         /* reset time & songposition */
 120         tmr->cur_time.tv_sec = 0;
 121         tmr->cur_time.tv_nsec = 0;
 122
 123         tmr->tick.cur_tick = 0;
 124         tmr->tick.fraction = 0;
 125
 126         spin_unlock_irqrestore(&tmr->lock, flags);
 127 }
 128
 129
 130 /* called by timer interrupt routine. the period time since previous invocation is passed */
 131 static void snd_seq_timer_interrupt(struct snd_timer_instance *timeri,
 132                                     unsigned long resolution,
 133                                     unsigned long ticks)
 134 {
 135         unsigned long flags;
 136         struct snd_seq_queue *q = timeri->callback_data;
 137         struct snd_seq_timer *tmr;
 138
 139         if (q == NULL)
 140                 return;
 141         tmr = q->timer;
 142         if (tmr == NULL)
 143                 return;
 144         if (!tmr->running)
 145                 return;
 146
 147         resolution *= ticks;
 148         if (tmr->skew != tmr->skew_base) {
 149                 /* FIXME: assuming skew_base = 0x10000 */
 150                 resolution = (resolution >> 16) * tmr->skew +
 151                         (((resolution & 0xffff) * tmr->skew) >> 16);
 152         }
 153
 154         spin_lock_irqsave(&tmr->lock, flags);
 155
 156         /* update timer */
 157         snd_seq_inc_time_nsec(&tmr->cur_time, resolution);
 158
 159         /* calculate current tick */
 160         snd_seq_timer_update_tick(&tmr->tick, resolution);
 161
 162         /* register actual time of this timer update */
 163         do_gettimeofday(&tmr->last_update);
 164
 165         spin_unlock_irqrestore(&tmr->lock, flags);
 166
 167         /* check queues and dispatch events */
 168         snd_seq_check_queue(q, 1, 0);
 169 }
 170
 171 /* set current tempo */
 172 int snd_seq_timer_set_tempo(struct snd_seq_timer * tmr, int tempo)
 173 {
 174         unsigned long flags;
 175
 176         if (snd_BUG_ON(!tmr))
 177                 return -EINVAL;
 178         if (tempo <= 0)
 179                 return -EINVAL;
 180         spin_lock_irqsave(&tmr->lock, flags);
 181         if ((unsigned int)tempo != tmr->tempo) {
 182                 tmr->tempo = tempo;
 183                 snd_seq_timer_set_tick_resolution(&tmr->tick, tmr->tempo, tmr->ppq);
 184         }
 185         spin_unlock_irqrestore(&tmr->lock, flags);
 186         return 0;
 187 }
 188
 189 /* set current ppq */
 190 int snd_seq_timer_set_ppq(struct snd_seq_timer * tmr, int ppq)
 191 {
 192         unsigned long flags;
 193
 194         if (snd_BUG_ON(!tmr))
 195                 return -EINVAL;
 196         if (ppq <= 0)
 197                 return -EINVAL;
 198         spin_lock_irqsave(&tmr->lock, flags);
 199         if (tmr->running && (ppq != tmr->ppq)) {
 200                 /* refuse to change ppq on running timers */
 201                 /* because it will upset the song position (ticks) */
 202                 spin_unlock_irqrestore(&tmr->lock, flags);
 203                 snd_printd("seq: cannot change ppq of a running timer\n");
 204                 return -EBUSY;
 205         }
 206
 207         tmr->ppq = ppq;
 208         snd_seq_timer_set_tick_resolution(&tmr->tick, tmr->tempo, tmr->ppq);
 209         spin_unlock_irqrestore(&tmr->lock, flags);
 210         return 0;
 211 }
 212
 213 /* set current tick position */
 214 int snd_seq_timer_set_position_tick(struct snd_seq_timer *tmr,
 215                                     snd_seq_tick_time_t position)
 216 {
 217         unsigned long flags;
 218
 219         if (snd_BUG_ON(!tmr))
 220                 return -EINVAL;
 221
 222         spin_lock_irqsave(&tmr->lock, flags);
 223         tmr->tick.cur_tick = position;
 224         tmr->tick.fraction = 0;
 225         spin_unlock_irqrestore(&tmr->lock, flags);
 226         return 0;
 227 }
 228
 229 /* set current real-time position */
 230 int snd_seq_timer_set_position_time(struct snd_seq_timer *tmr,
 231                                     snd_seq_real_time_t position)
 232 {
 233         unsigned long flags;
 234
 235         if (snd_BUG_ON(!tmr))
 236                 return -EINVAL;
 237
 238         snd_seq_sanity_real_time(&position);
 239         spin_lock_irqsave(&tmr->lock, flags);
 240         tmr->cur_time = position;
 241         spin_unlock_irqrestore(&tmr->lock, flags);
 242         return 0;
 243 }
 244
 245 /* set timer skew */
 246 int snd_seq_timer_set_skew(struct snd_seq_timer *tmr, unsigned int skew,
 247                            unsigned int base)
 248 {
 249         unsigned long flags;
 250
 251         if (snd_BUG_ON(!tmr))
 252                 return -EINVAL;
 253
 254         /* FIXME */
 255         if (base != SKEW_BASE) {
 256                 snd_printd("invalid skew base 0x%x\n", base);
 257                 return -EINVAL;
 258         }
 259         spin_lock_irqsave(&tmr->lock, flags);
 260         tmr->skew = skew;
 261         spin_unlock_irqrestore(&tmr->lock, flags);
 262         return 0;
 263 }
 264
 265 int snd_seq_timer_open(struct snd_seq_queue *q)
 266 {
 267         struct snd_timer_instance *t;
 268         struct snd_seq_timer *tmr;
 269         char str[32];
 270         int err;
 271
 272         tmr = q->timer;
 273         if (snd_BUG_ON(!tmr))
 274                 return -EINVAL;
 275         if (tmr->timeri)
 276                 return -EBUSY;
 277         sprintf(str, "sequencer queue %i", q->queue);
 278         if (tmr->type != SNDRV_SEQ_TIMER_ALSA)  /* standard ALSA timer */
 279                 return -EINVAL;
 280         if (tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_SLAVE)
 281                 tmr->alsa_id.dev_sclass = SNDRV_TIMER_SCLASS_SEQUENCER;
 282         err = snd_timer_open(&t, str, &tmr->alsa_id, q->queue);
 283         if (err < 0 && tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_SLAVE) {
 284                 if (tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_GLOBAL ||
 285                     tmr->alsa_id.device != SNDRV_TIMER_GLOBAL_SYSTEM) {
 286                         struct snd_timer_id tid;
 287                         memset(&tid, 0, sizeof(tid));
 288                         tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL;
 289                         tid.dev_sclass = SNDRV_TIMER_SCLASS_SEQUENCER;
 290                         tid.card = -1;
 291                         tid.device = SNDRV_TIMER_GLOBAL_SYSTEM;
 292                         err = snd_timer_open(&t, str, &tid, q->queue);
 293                 }
 294                 if (err < 0) {
 295                         snd_printk(KERN_ERR "seq fatal error: cannot create timer (%i)\n", err);
 296                         return err;
 297                 }
 298         }
 299         t->callback = snd_seq_timer_interrupt;
 300         t->callback_data = q;
 301         t->flags |= SNDRV_TIMER_IFLG_AUTO;
 302         tmr->timeri = t;
 303         return 0;
 304 }
 305
 306 int snd_seq_timer_close(struct snd_seq_queue *q)
 307 {
 308         struct snd_seq_timer *tmr;
 309
 310         tmr = q->timer;
 311         if (snd_BUG_ON(!tmr))
 312                 return -EINVAL;
 313         if (tmr->timeri) {
 314                 snd_timer_stop(tmr->timeri);
 315                 snd_timer_close(tmr->timeri);
 316                 tmr->timeri = NULL;
 317         }
 318         return 0;
 319 }
 320
 321 int snd_seq_timer_stop(struct snd_seq_timer * tmr)
 322 {
 323         if (! tmr->timeri)
 324                 return -EINVAL;
 325         if (!tmr->running)
 326                 return 0;
 327         tmr->running = 0;
 328         snd_timer_pause(tmr->timeri);
 329         return 0;
 330 }
 331
 332 static int initialize_timer(struct snd_seq_timer *tmr)
 333 {
 334         struct snd_timer *t;
 335         unsigned long freq;
 336
 337         t = tmr->timeri->timer;
 338         if (snd_BUG_ON(!t))
 339                 return -EINVAL;
 340
 341         freq = tmr->preferred_resolution;
 342         if (!freq)
 343                 freq = DEFAULT_FREQUENCY;
 344         else if (freq < MIN_FREQUENCY)
 345                 freq = MIN_FREQUENCY;
 346         else if (freq > MAX_FREQUENCY)
 347                 freq = MAX_FREQUENCY;
 348
 349         tmr->ticks = 1;
 350         if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE)) {
 351                 unsigned long r = t->hw.resolution;
 352                 if (! r && t->hw.c_resolution)
 353                         r = t->hw.c_resolution(t);
 354                 if (r) {
 355                         tmr->ticks = (unsigned int)(1000000000uL / (r * freq));
 356                         if (! tmr->ticks)
 357                                 tmr->ticks = 1;
 358                 }
 359         }
 360         tmr->initialized = 1;
 361         return 0;
 362 }
 363
 364 int snd_seq_timer_start(struct snd_seq_timer * tmr)
 365 {
 366         if (! tmr->timeri)
 367                 return -EINVAL;
 368         if (tmr->running)
 369                 snd_seq_timer_stop(tmr);
 370         snd_seq_timer_reset(tmr);
 371         if (initialize_timer(tmr) < 0)
 372                 return -EINVAL;
 373         snd_timer_start(tmr->timeri, tmr->ticks);
 374         tmr->running = 1;
 375         do_gettimeofday(&tmr->last_update);
 376         return 0;
 377 }
 378
 379 int snd_seq_timer_continue(struct snd_seq_timer * tmr)
 380 {
 381         if (! tmr->timeri)
 382                 return -EINVAL;
 383         if (tmr->running)
 384                 return -EBUSY;
 385         if (! tmr->initialized) {
 386                 snd_seq_timer_reset(tmr);
 387                 if (initialize_timer(tmr) < 0)
 388                         return -EINVAL;
 389         }
 390         snd_timer_start(tmr->timeri, tmr->ticks);
 391         tmr->running = 1;
 392         do_gettimeofday(&tmr->last_update);
 393         return 0;
 394 }
 395
 396 /* return current 'real' time. use timeofday() to get better granularity. */
 397 snd_seq_real_time_t snd_seq_timer_get_cur_time(struct snd_seq_timer *tmr)
 398 {
 399         snd_seq_real_time_t cur_time;
 400
 401         cur_time = tmr->cur_time;
 402         if (tmr->running) {
 403                 struct timeval tm;
 404                 int usec;
 405                 do_gettimeofday(&tm);
 406                 usec = (int)(tm.tv_usec - tmr->last_update.tv_usec);
 407                 if (usec < 0) {
 408                         cur_time.tv_nsec += (1000000 + usec) * 1000;
 409                         cur_time.tv_sec += tm.tv_sec - tmr->last_update.tv_sec - 1;
 410                 } else {
 411                         cur_time.tv_nsec += usec * 1000;
 412                         cur_time.tv_sec += tm.tv_sec - tmr->last_update.tv_sec;
 413                 }
 414                 snd_seq_sanity_real_time(&cur_time);
 415         }
 416
 417         return cur_time;
 418 }
 419
 420 /* TODO: use interpolation on tick queue (will only be useful for very
 421  high PPQ values) */
 422 snd_seq_tick_time_t snd_seq_timer_get_cur_tick(struct snd_seq_timer *tmr)
 423 {
 424         return tmr->tick.cur_tick;
 425 }
 426
 427
 428 #ifdef CONFIG_PROC_FS
 429 /* exported to seq_info.c */
 430 void snd_seq_info_timer_read(struct snd_info_entry *entry,
 431                              struct snd_info_buffer *buffer)
 432 {
 433         int idx;
 434         struct snd_seq_queue *q;
 435         struct snd_seq_timer *tmr;
 436         struct snd_timer_instance *ti;
 437         unsigned long resolution;
 438
 439         for (idx = 0; idx < SNDRV_SEQ_MAX_QUEUES; idx++) {
 440                 q = queueptr(idx);
 441                 if (q == NULL)
 442                         continue;
 443                 if ((tmr = q->timer) == NULL ||
 444                     (ti = tmr->timeri) == NULL) {
 445                         queuefree(q);
 446                         continue;
 447                 }
 448                 snd_iprintf(buffer, "Timer for queue %i : %s\n", q->queue, ti->timer->name);
 449                 resolution = snd_timer_resolution(ti) * tmr->ticks;
 450                 snd_iprintf(buffer, "  Period time : %lu.%09lu\n", resolution / 1000000000, resolution % 1000000000);
 451                 snd_iprintf(buffer, "  Skew : %u / %u\n", tmr->skew, tmr->skew_base);
 452                 queuefree(q);
 453         }
 454 }
 455 #endif /* CONFIG_PROC_FS */
 456