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         snd_assert(tmr, 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->tick, tmr->tempo, tmr->ppq);
 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         snd_assert(tmr, return -EINVAL);
 194         if (ppq <= 0)
 195                 return -EINVAL;
 196         spin_lock_irqsave(&tmr->lock, flags);
 197         if (tmr->running && (ppq != tmr->ppq)) {
 198                 /* refuse to change ppq on running timers */
 199                 /* because it will upset the song position (ticks) */
 200                 spin_unlock_irqrestore(&tmr->lock, flags);
 201                 snd_printd("seq: cannot change ppq of a running timer\n");
 202                 return -EBUSY;
 203         }
 204
 205         tmr->ppq = ppq;
 206         snd_seq_timer_set_tick_resolution(&tmr->tick, tmr->tempo, tmr->ppq);
 207         spin_unlock_irqrestore(&tmr->lock, flags);
 208         return 0;
 209 }
 210
 211 /* set current tick position */
 212 int snd_seq_timer_set_position_tick(struct snd_seq_timer *tmr,
 213                                     snd_seq_tick_time_t position)
 214 {
 215         unsigned long flags;
 216
 217         snd_assert(tmr, 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         snd_assert(tmr, return -EINVAL);
 233
 234         snd_seq_sanity_real_time(&position);
 235         spin_lock_irqsave(&tmr->lock, flags);
 236         tmr->cur_time = position;
 237         spin_unlock_irqrestore(&tmr->lock, flags);
 238         return 0;
 239 }
 240
 241 /* set timer skew */
 242 int snd_seq_timer_set_skew(struct snd_seq_timer *tmr, unsigned int skew,
 243                            unsigned int base)
 244 {
 245         unsigned long flags;
 246
 247         snd_assert(tmr, return -EINVAL);
 248
 249         /* FIXME */
 250         if (base != SKEW_BASE) {
 251                 snd_printd("invalid skew base 0x%x\n", base);
 252                 return -EINVAL;
 253         }
 254         spin_lock_irqsave(&tmr->lock, flags);
 255         tmr->skew = skew;
 256         spin_unlock_irqrestore(&tmr->lock, flags);
 257         return 0;
 258 }
 259
 260 int snd_seq_timer_open(struct snd_seq_queue *q)
 261 {
 262         struct snd_timer_instance *t;
 263         struct snd_seq_timer *tmr;
 264         char str[32];
 265         int err;
 266
 267         tmr = q->timer;
 268         snd_assert(tmr != NULL, return -EINVAL);
 269         if (tmr->timeri)
 270                 return -EBUSY;
 271         sprintf(str, "sequencer queue %i", q->queue);
 272         if (tmr->type != SNDRV_SEQ_TIMER_ALSA)  /* standard ALSA timer */
 273                 return -EINVAL;
 274         if (tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_SLAVE)
 275                 tmr->alsa_id.dev_sclass = SNDRV_TIMER_SCLASS_SEQUENCER;
 276         err = snd_timer_open(&t, str, &tmr->alsa_id, q->queue);
 277         if (err < 0 && tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_SLAVE) {
 278                 if (tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_GLOBAL ||
 279                     tmr->alsa_id.device != SNDRV_TIMER_GLOBAL_SYSTEM) {
 280                         struct snd_timer_id tid;
 281                         memset(&tid, 0, sizeof(tid));
 282                         tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL;
 283                         tid.dev_sclass = SNDRV_TIMER_SCLASS_SEQUENCER;
 284                         tid.card = -1;
 285                         tid.device = SNDRV_TIMER_GLOBAL_SYSTEM;
 286                         err = snd_timer_open(&t, str, &tid, q->queue);
 287                 }
 288                 if (err < 0) {
 289                         snd_printk(KERN_ERR "seq fatal error: cannot create timer (%i)\n", err);
 290                         return err;
 291                 }
 292         }
 293         t->callback = snd_seq_timer_interrupt;
 294         t->callback_data = q;
 295         t->flags |= SNDRV_TIMER_IFLG_AUTO;
 296         tmr->timeri = t;
 297         return 0;
 298 }
 299
 300 int snd_seq_timer_close(struct snd_seq_queue *q)
 301 {
 302         struct snd_seq_timer *tmr;
 303
 304         tmr = q->timer;
 305         snd_assert(tmr != NULL, return -EINVAL);
 306         if (tmr->timeri) {
 307                 snd_timer_stop(tmr->timeri);
 308                 snd_timer_close(tmr->timeri);
 309                 tmr->timeri = NULL;
 310         }
 311         return 0;
 312 }
 313
 314 int snd_seq_timer_stop(struct snd_seq_timer * tmr)
 315 {
 316         if (! tmr->timeri)
 317                 return -EINVAL;
 318         if (!tmr->running)
 319                 return 0;
 320         tmr->running = 0;
 321         snd_timer_pause(tmr->timeri);
 322         return 0;
 323 }
 324
 325 static int initialize_timer(struct snd_seq_timer *tmr)
 326 {
 327         struct snd_timer *t;
 328         unsigned long freq;
 329
 330         t = tmr->timeri->timer;
 331         snd_assert(t, return -EINVAL);
 332
 333         freq = tmr->preferred_resolution;
 334         if (!freq)
 335                 freq = DEFAULT_FREQUENCY;
 336         else if (freq < MIN_FREQUENCY)
 337                 freq = MIN_FREQUENCY;
 338         else if (freq > MAX_FREQUENCY)
 339                 freq = MAX_FREQUENCY;
 340
 341         tmr->ticks = 1;
 342         if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE)) {
 343                 unsigned long r = t->hw.resolution;
 344                 if (! r && t->hw.c_resolution)
 345                         r = t->hw.c_resolution(t);
 346                 if (r) {
 347                         tmr->ticks = (unsigned int)(1000000000uL / (r * freq));
 348                         if (! tmr->ticks)
 349                                 tmr->ticks = 1;
 350                 }
 351         }
 352         tmr->initialized = 1;
 353         return 0;
 354 }
 355
 356 int snd_seq_timer_start(struct snd_seq_timer * tmr)
 357 {
 358         if (! tmr->timeri)
 359                 return -EINVAL;
 360         if (tmr->running)
 361                 snd_seq_timer_stop(tmr);
 362         snd_seq_timer_reset(tmr);
 363         if (initialize_timer(tmr) < 0)
 364                 return -EINVAL;
 365         snd_timer_start(tmr->timeri, tmr->ticks);
 366         tmr->running = 1;
 367         do_gettimeofday(&tmr->last_update);
 368         return 0;
 369 }
 370
 371 int snd_seq_timer_continue(struct snd_seq_timer * tmr)
 372 {
 373         if (! tmr->timeri)
 374                 return -EINVAL;
 375         if (tmr->running)
 376                 return -EBUSY;
 377         if (! tmr->initialized) {
 378                 snd_seq_timer_reset(tmr);
 379                 if (initialize_timer(tmr) < 0)
 380                         return -EINVAL;
 381         }
 382         snd_timer_start(tmr->timeri, tmr->ticks);
 383         tmr->running = 1;
 384         do_gettimeofday(&tmr->last_update);
 385         return 0;
 386 }
 387
 388 /* return current 'real' time. use timeofday() to get better granularity. */
 389 snd_seq_real_time_t snd_seq_timer_get_cur_time(struct snd_seq_timer *tmr)
 390 {
 391         snd_seq_real_time_t cur_time;
 392
 393         cur_time = tmr->cur_time;
 394         if (tmr->running) {
 395                 struct timeval tm;
 396                 int usec;
 397                 do_gettimeofday(&tm);
 398                 usec = (int)(tm.tv_usec - tmr->last_update.tv_usec);
 399                 if (usec < 0) {
 400                         cur_time.tv_nsec += (1000000 + usec) * 1000;
 401                         cur_time.tv_sec += tm.tv_sec - tmr->last_update.tv_sec - 1;
 402                 } else {
 403                         cur_time.tv_nsec += usec * 1000;
 404                         cur_time.tv_sec += tm.tv_sec - tmr->last_update.tv_sec;
 405                 }
 406                 snd_seq_sanity_real_time(&cur_time);
 407         }
 408
 409         return cur_time;
 410 }
 411
 412 /* TODO: use interpolation on tick queue (will only be useful for very
 413  high PPQ values) */
 414 snd_seq_tick_time_t snd_seq_timer_get_cur_tick(struct snd_seq_timer *tmr)
 415 {
 416         return tmr->tick.cur_tick;
 417 }
 418
 419
 420 #ifdef CONFIG_PROC_FS
 421 /* exported to seq_info.c */
 422 void snd_seq_info_timer_read(struct snd_info_entry *entry,
 423                              struct snd_info_buffer *buffer)
 424 {
 425         int idx;
 426         struct snd_seq_queue *q;
 427         struct snd_seq_timer *tmr;
 428         struct snd_timer_instance *ti;
 429         unsigned long resolution;
 430
 431         for (idx = 0; idx < SNDRV_SEQ_MAX_QUEUES; idx++) {
 432                 q = queueptr(idx);
 433                 if (q == NULL)
 434                         continue;
 435                 if ((tmr = q->timer) == NULL ||
 436                     (ti = tmr->timeri) == NULL) {
 437                         queuefree(q);
 438                         continue;
 439                 }
 440                 snd_iprintf(buffer, "Timer for queue %i : %s\n", q->queue, ti->timer->name);
 441                 resolution = snd_timer_resolution(ti) * tmr->ticks;
 442                 snd_iprintf(buffer, "  Period time : %lu.%09lu\n", resolution / 1000000000, resolution % 1000000000);
 443                 snd_iprintf(buffer, "  Skew : %u / %u\n", tmr->skew, tmr->skew_base);
 444                 queuefree(q);
 445         }
 446 }
 447 #endif /* CONFIG_PROC_FS */
 448