drivers/sound/sys_timer.c

   1 /*
   2  * sound/sys_timer.c
   3  *
   4  * The default timer for the Level 2 sequencer interface
   5  * Uses the (100HZ) timer of kernel.
   6  *
   7  * Copyright by Hannu Savolainen 1993
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions are
  11  * met: 1. Redistributions of source code must retain the above copyright
  12  * notice, this list of conditions and the following disclaimer. 2.
  13  * Redistributions in binary form must reproduce the above copyright notice,
  14  * this list of conditions and the following disclaimer in the documentation
  15  * and/or other materials provided with the distribution.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
  18  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  19  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  20  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
  21  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  23  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  24  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  */
  30
  31 #define SEQUENCER_C
  32 #include "sound_config.h"
  33
  34 #ifdef CONFIGURE_SOUNDCARD
  35
  36 #ifndef EXCLUDE_SEQUENCER
  37
  38 static volatile int opened = 0, tmr_running = 0;
  39 static volatile time_t tmr_offs, tmr_ctr;
  40 static volatile unsigned long ticks_offs;
  41 static volatile int curr_tempo, curr_timebase;
  42 static volatile unsigned long curr_ticks;
  43 static volatile unsigned long next_event_time;
  44 static unsigned long prev_event_time;
  45
  46 static void     poll_def_tmr (unsigned long dummy);
  47
  48
  49 static struct timer_list def_tmr =
  50 {NULL, NULL, 0, 0, poll_def_tmr};
  51
  52 static unsigned long
  53 tmr2ticks (int tmr_value)
  54 {
  55   /*
  56    *    Convert system timer ticks (HZ) to MIDI ticks
  57    *    (divide # of MIDI ticks/minute by # of system ticks/minute).
  58    */
  59
  60   return ((tmr_value * curr_tempo * curr_timebase) + (30 * HZ)) / (60 * HZ);
  61 }
  62
  63 static void
  64 poll_def_tmr (unsigned long dummy)
  65 {
  66
  67   if (opened)
  68     {
  69
  70       {
  71         def_tmr.expires = (1) + jiffies;
  72         add_timer (&def_tmr);
  73       };
  74
  75       if (tmr_running)
  76         {
  77           tmr_ctr++;
  78           curr_ticks = ticks_offs + tmr2ticks (tmr_ctr);
  79
  80           if (curr_ticks >= next_event_time)
  81             {
  82               next_event_time = 0xffffffff;
  83               sequencer_timer (0);
  84             }
  85         }
  86     }
  87 }
  88
  89 static void
  90 tmr_reset (void)
  91 {
  92   unsigned long   flags;
  93
  94   save_flags (flags);
  95   cli ();
  96   tmr_offs = 0;
  97   ticks_offs = 0;
  98   tmr_ctr = 0;
  99   next_event_time = 0xffffffff;
 100   prev_event_time = 0;
 101   curr_ticks = 0;
 102   restore_flags (flags);
 103 }
 104
 105 static int
 106 def_tmr_open (int dev, int mode)
 107 {
 108   if (opened)
 109     return -EBUSY;
 110
 111   tmr_reset ();
 112   curr_tempo = 60;
 113   curr_timebase = HZ;
 114   opened = 1;
 115
 116
 117   {
 118     def_tmr.expires = (1) + jiffies;
 119     add_timer (&def_tmr);
 120   };
 121
 122   return 0;
 123 }
 124
 125 static void
 126 def_tmr_close (int dev)
 127 {
 128   opened = tmr_running = 0;
 129   del_timer (&def_tmr);;
 130 }
 131
 132 static int
 133 def_tmr_event (int dev, unsigned char *event)
 134 {
 135   unsigned char   cmd = event[1];
 136   unsigned long   parm = *(int *) &event[4];
 137
 138   switch (cmd)
 139     {
 140     case TMR_WAIT_REL:
 141       parm += prev_event_time;
 142     case TMR_WAIT_ABS:
 143       if (parm > 0)
 144         {
 145           long            time;
 146
 147           if (parm <= curr_ticks)       /* It's the time */
 148             return TIMER_NOT_ARMED;
 149
 150           time = parm;
 151           next_event_time = prev_event_time = time;
 152
 153           return TIMER_ARMED;
 154         }
 155       break;
 156
 157     case TMR_START:
 158       tmr_reset ();
 159       tmr_running = 1;
 160       break;
 161
 162     case TMR_STOP:
 163       tmr_running = 0;
 164       break;
 165
 166     case TMR_CONTINUE:
 167       tmr_running = 1;
 168       break;
 169
 170     case TMR_TEMPO:
 171       if (parm)
 172         {
 173           if (parm < 8)
 174             parm = 8;
 175           if (parm > 360)
 176             parm = 360;
 177           tmr_offs = tmr_ctr;
 178           ticks_offs += tmr2ticks (tmr_ctr);
 179           tmr_ctr = 0;
 180           curr_tempo = parm;
 181         }
 182       break;
 183
 184     case TMR_ECHO:
 185       seq_copy_to_input (event, 8);
 186       break;
 187
 188     default:;
 189     }
 190
 191   return TIMER_NOT_ARMED;
 192 }
 193
 194 static unsigned long
 195 def_tmr_get_time (int dev)
 196 {
 197   if (!opened)
 198     return 0;
 199
 200   return curr_ticks;
 201 }
 202
 203 static int
 204 def_tmr_ioctl (int dev,
 205                unsigned int cmd, ioctl_arg arg)
 206 {
 207   switch (cmd)
 208     {
 209     case SNDCTL_TMR_SOURCE:
 210       return snd_ioctl_return ((int *) arg, TMR_INTERNAL);
 211       break;
 212
 213     case SNDCTL_TMR_START:
 214       tmr_reset ();
 215       tmr_running = 1;
 216       return 0;
 217       break;
 218
 219     case SNDCTL_TMR_STOP:
 220       tmr_running = 0;
 221       return 0;
 222       break;
 223
 224     case SNDCTL_TMR_CONTINUE:
 225       tmr_running = 1;
 226       return 0;
 227       break;
 228
 229     case SNDCTL_TMR_TIMEBASE:
 230       {
 231         int             val = get_fs_long ((long *) arg);
 232
 233         if (val)
 234           {
 235             if (val < 1)
 236               val = 1;
 237             if (val > 1000)
 238               val = 1000;
 239             curr_timebase = val;
 240           }
 241
 242         return snd_ioctl_return ((int *) arg, curr_timebase);
 243       }
 244       break;
 245
 246     case SNDCTL_TMR_TEMPO:
 247       {
 248         int             val = get_fs_long ((long *) arg);
 249
 250         if (val)
 251           {
 252             if (val < 8)
 253               val = 8;
 254             if (val > 250)
 255               val = 250;
 256             tmr_offs = tmr_ctr;
 257             ticks_offs += tmr2ticks (tmr_ctr);
 258             tmr_ctr = 0;
 259             curr_tempo = val;
 260           }
 261
 262         return snd_ioctl_return ((int *) arg, curr_tempo);
 263       }
 264       break;
 265
 266     case SNDCTL_SEQ_CTRLRATE:
 267       if (get_fs_long ((long *) arg) != 0)      /* Can't change */
 268         return -EINVAL;
 269
 270       return snd_ioctl_return ((int *) arg, ((curr_tempo * curr_timebase) + 30) / 60);
 271       break;
 272
 273     case SNDCTL_TMR_METRONOME:
 274       /* NOP */
 275       break;
 276
 277     default:;
 278     }
 279
 280   return -EINVAL;
 281 }
 282
 283 static void
 284 def_tmr_arm (int dev, long time)
 285 {
 286   if (time < 0)
 287     time = curr_ticks + 1;
 288   else if (time <= curr_ticks)  /* It's the time */
 289     return;
 290
 291   next_event_time = prev_event_time = time;
 292
 293   return;
 294 }
 295
 296 struct sound_timer_operations default_sound_timer =
 297 {
 298   {"System clock", 0},
 299   0,                            /* Priority */
 300   0,                            /* Local device link */
 301   def_tmr_open,
 302   def_tmr_close,
 303   def_tmr_event,
 304   def_tmr_get_time,
 305   def_tmr_ioctl,
 306   def_tmr_arm
 307 };
 308
 309 #endif
 310 #endif