drivers/sound/sys

/* */
This source file includes following definitions.
tmr2ticks
poll_def_tmr
tmr_reset
def_tmr_open
def_tmr_close
def_tmr_event
def_tmr_get_time
def_tmr_ioctl
def_tmr_arm
   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 DEFINE_TIMER (def_tmr, poll_def_tmr);
  49 
  50 static unsigned long
  51 tmr2ticks (int tmr_value)
     /*  */
  52 {
  53   /*
  54  *    Convert system timer ticks (HZ) to MIDI ticks
  55  */
  56 
  57   unsigned long   tmp;
  58   unsigned long   scale;
  59 
  60   tmp = (tmr_value * 1000) / HZ;/* Convert to msecs */
  61 
  62   scale = (60 * 1000) / (curr_tempo * curr_timebase);   /* msecs per MIDI tick */
  63 
  64   return (tmp + (scale / 2)) / scale;
  65 }
  66 
  67 static void
  68 poll_def_tmr (unsigned long dummy)
     /*  */
  69 {
  70 
  71   if (opened)
  72     {
  73       ACTIVATE_TIMER (def_tmr, poll_def_tmr, 1);
  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 ();
  84             }
  85         }
  86     }
  87 }
  88 
  89 static void
  90 tmr_reset (void)
     /*  */
  91 {
  92   unsigned long   flags;
  93 
  94   DISABLE_INTR (flags);
  95   tmr_offs = 0;
  96   ticks_offs = 0;
  97   tmr_ctr = 0;
  98   next_event_time = 0xffffffff;
  99   prev_event_time = 0;
 100   curr_ticks = 0;
 101   RESTORE_INTR (flags);
 102 }
 103 
 104 static int
 105 def_tmr_open (int dev, int mode)
     /*  */
 106 {
 107   if (opened)
 108     return RET_ERROR (EBUSY);
 109 
 110   tmr_reset ();
 111   curr_tempo = 60;
 112   curr_timebase = HZ;
 113   opened = 1;
 114 
 115   ACTIVATE_TIMER (def_tmr, poll_def_tmr, 1);
 116 
 117   return 0;
 118 }
 119 
 120 static void
 121 def_tmr_close (int dev)
     /*  */
 122 {
 123   opened = tmr_running = 0;
 124 }
 125 
 126 static int
 127 def_tmr_event (int dev, unsigned char *event)
     /*  */
 128 {
 129   unsigned char   cmd = event[1];
 130   unsigned long   parm = *(int *) &event[4];
 131 
 132   switch (cmd)
 133     {
 134     case TMR_WAIT_REL:
 135       parm += prev_event_time;
 136     case TMR_WAIT_ABS:
 137       if (parm > 0)
 138         {
 139           long            time;
 140 
 141           if (parm <= curr_ticks)       /* It's the time */
 142             return TIMER_NOT_ARMED;
 143 
 144           time = parm;
 145           next_event_time = prev_event_time = time;
 146 
 147           return TIMER_ARMED;
 148         }
 149       break;
 150 
 151     case TMR_START:
 152       tmr_reset ();
 153       tmr_running = 1;
 154       break;
 155 
 156     case TMR_STOP:
 157       tmr_running = 0;
 158       break;
 159 
 160     case TMR_CONTINUE:
 161       tmr_running = 1;
 162       break;
 163 
 164     case TMR_TEMPO:
 165       if (parm)
 166         {
 167           if (parm < 8)
 168             parm = 8;
 169           if (parm > 250)
 170             parm = 250;
 171           tmr_offs = tmr_ctr;
 172           ticks_offs += tmr2ticks (tmr_ctr);
 173           tmr_ctr = 0;
 174           curr_tempo = parm;
 175         }
 176       break;
 177 
 178     case TMR_ECHO:
 179       seq_copy_to_input (event, 8);
 180       break;
 181 
 182     default:;
 183     }
 184 
 185   return TIMER_NOT_ARMED;
 186 }
 187 
 188 static unsigned long
 189 def_tmr_get_time (int dev)
     /*  */
 190 {
 191   if (!opened)
 192     return 0;
 193 
 194   return curr_ticks;
 195 }
 196 
 197 static int
 198 def_tmr_ioctl (int dev,
     /*  */
 199                unsigned int cmd, unsigned int arg)
 200 {
 201   switch (cmd)
 202     {
 203     case SNDCTL_TMR_SOURCE:
 204       return IOCTL_OUT (arg, TMR_INTERNAL);
 205       break;
 206 
 207     case SNDCTL_TMR_START:
 208       tmr_reset ();
 209       tmr_running = 1;
 210       return 0;
 211       break;
 212 
 213     case SNDCTL_TMR_STOP:
 214       tmr_running = 0;
 215       return 0;
 216       break;
 217 
 218     case SNDCTL_TMR_CONTINUE:
 219       tmr_running = 1;
 220       return 0;
 221       break;
 222 
 223     case SNDCTL_TMR_TIMEBASE:
 224       {
 225         int             val = IOCTL_IN (arg);
 226 
 227         if (val)
 228           {
 229             if (val < 1)
 230               val = 1;
 231             if (val > 1000)
 232               val = 1000;
 233             curr_timebase = val;
 234           }
 235 
 236         return IOCTL_OUT (arg, curr_timebase);
 237       }
 238       break;
 239 
 240     case SNDCTL_TMR_TEMPO:
 241       {
 242         int             val = IOCTL_IN (arg);
 243 
 244         if (val)
 245           {
 246             if (val < 8)
 247               val = 8;
 248             if (val > 250)
 249               val = 250;
 250             tmr_offs = tmr_ctr;
 251             ticks_offs += tmr2ticks (tmr_ctr);
 252             tmr_ctr = 0;
 253             curr_tempo = val;
 254           }
 255 
 256         return IOCTL_OUT (arg, curr_tempo);
 257       }
 258       break;
 259 
 260     case SNDCTL_SEQ_CTRLRATE:
 261       if (IOCTL_IN (arg) != 0)  /* Can't change */
 262         return RET_ERROR (EINVAL);
 263 
 264       return IOCTL_OUT (arg, ((curr_tempo * curr_timebase) + 30) / 60);
 265       break;
 266 
 267     case SNDCTL_TMR_METRONOME:
 268       /* NOP */
 269       break;
 270 
 271     default:;
 272     }
 273 
 274   return RET_ERROR (EINVAL);
 275 }
 276 
 277 static void
 278 def_tmr_arm (int dev, long time)
     /*  */
 279 {
 280   if (time < 0)
 281     time = curr_ticks + 1;
 282   else if (time <= curr_ticks)  /* It's the time */
 283     return;
 284 
 285   next_event_time = prev_event_time = time;
 286 
 287   return;
 288 }
 289 
 290 struct sound_timer_operations default_sound_timer =
 291 {
 292   {"System Timer", 0},
 293   0,                            /* Priority */
 294   0,                            /* Local device link */
 295   def_tmr_open,
 296   def_tmr_close,
 297   def_tmr_event,
 298   def_tmr_get_time,
 299   def_tmr_ioctl,
 300   def_tmr_arm
 301 };
 302 
 303 #endif
 304 #endif
/* */
root/drivers/sound/sys_timer.c

DEFINITIONS
