drivers/sound/midibuf.c

/* */
This source file includes following definitions.
drain_midi_queue
midi_input_intr
midi_output_intr
midi_poll
MIDIbuf_open
MIDIbuf_release
MIDIbuf_write
MIDIbuf_read
MIDIbuf_ioctl
MIDIbuf_select
MIDIbuf_init
   1 /*
   2  * sound/midibuf.c
   3  *
   4  * Device file manager for /dev/midi#
   5  *
   6  * Copyright by Hannu Savolainen 1993
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions are
  10  * met: 1. Redistributions of source code must retain the above copyright
  11  * notice, this list of conditions and the following disclaimer. 2.
  12  * Redistributions in binary form must reproduce the above copyright notice,
  13  * this list of conditions and the following disclaimer in the documentation
  14  * and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
  17  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  18  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  19  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
  20  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  22  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  23  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  *
  28  */
  29 
  30 #include "sound_config.h"
  31 
  32 #if defined(CONFIGURE_SOUNDCARD) && !defined(EXCLUDE_MIDI)
  33 
  34 /*
  35  * Don't make MAX_QUEUE_SIZE larger than 4000
  36  */
  37 
  38 #define MAX_QUEUE_SIZE  4000
  39 
  40 static struct wait_queue *midi_sleeper[MAX_MIDI_DEV] =
  41 {NULL};
  42 static volatile struct snd_wait midi_sleep_flag[MAX_MIDI_DEV] =
  43 {
  44   {0}};
  45 static struct wait_queue *input_sleeper[MAX_MIDI_DEV] =
  46 {NULL};
  47 static volatile struct snd_wait input_sleep_flag[MAX_MIDI_DEV] =
  48 {
  49   {0}};
  50 
  51 struct midi_buf
  52   {
  53     int             len, head, tail;
  54     unsigned char   queue[MAX_QUEUE_SIZE];
  55   };
  56 
  57 struct midi_parms
  58   {
  59     int             prech_timeout;      /*
  60                                          * Timeout before the first ch
  61                                          */
  62   };
  63 
  64 static struct midi_buf *midi_out_buf[MAX_MIDI_DEV] =
  65 {NULL};
  66 static struct midi_buf *midi_in_buf[MAX_MIDI_DEV] =
  67 {NULL};
  68 static struct midi_parms parms[MAX_MIDI_DEV];
  69 
  70 static void     midi_poll (unsigned long dummy);
  71 
  72 
  73 static struct timer_list poll_timer =
  74 {NULL, NULL, 0, 0, midi_poll};
  75 static volatile int open_devs = 0;
  76 
  77 #define DATA_AVAIL(q) (q->len)
  78 #define SPACE_AVAIL(q) (MAX_QUEUE_SIZE - q->len)
  79 
  80 #define QUEUE_BYTE(q, data) \
  81         if (SPACE_AVAIL(q)) \
  82         { \
  83           unsigned long flags; \
  84           save_flags(flags);cli(); \
  85           q->queue[q->tail] = (data); \
  86           q->len++; q->tail = (q->tail+1) % MAX_QUEUE_SIZE; \
  87           restore_flags(flags); \
  88         }
  89 
  90 #define REMOVE_BYTE(q, data) \
  91         if (DATA_AVAIL(q)) \
  92         { \
  93           unsigned long flags; \
  94           save_flags(flags);cli(); \
  95           data = q->queue[q->head]; \
  96           q->len--; q->head = (q->head+1) % MAX_QUEUE_SIZE; \
  97           restore_flags(flags); \
  98         }
  99 
 100 void
 101 drain_midi_queue (int dev)
     /*  */
 102 {
 103 
 104   /*
 105    * Give the Midi driver time to drain its output queues
 106    */
 107 
 108   if (midi_devs[dev]->buffer_status != NULL)
 109     while (!(current->signal & ~current->blocked) &&
 110            midi_devs[dev]->buffer_status (dev))
 111 
 112       {
 113         unsigned long   tl;
 114 
 115         if (HZ / 10)
 116           current->timeout = tl = jiffies + (HZ / 10);
 117         else
 118           tl = 0xffffffff;
 119         midi_sleep_flag[dev].mode = WK_SLEEP;
 120         interruptible_sleep_on (&midi_sleeper[dev]);
 121         if (!(midi_sleep_flag[dev].mode & WK_WAKEUP))
 122           {
 123             if (jiffies >= tl)
 124               midi_sleep_flag[dev].mode |= WK_TIMEOUT;
 125           }
 126         midi_sleep_flag[dev].mode &= ~WK_SLEEP;
 127       };
 128 }
 129 
 130 static void
 131 midi_input_intr (int dev, unsigned char data)
     /*  */
 132 {
 133   if (midi_in_buf[dev] == NULL)
 134     return;
 135 
 136   if (data == 0xfe)             /*
 137                                  * Active sensing
 138                                  */
 139     return;                     /*
 140                                  * Ignore
 141                                  */
 142 
 143   if (SPACE_AVAIL (midi_in_buf[dev]))
 144     {
 145       QUEUE_BYTE (midi_in_buf[dev], data);
 146       if ((input_sleep_flag[dev].mode & WK_SLEEP))
 147         {
 148           input_sleep_flag[dev].mode = WK_WAKEUP;
 149           wake_up (&input_sleeper[dev]);
 150         };
 151     }
 152 
 153 }
 154 
 155 static void
 156 midi_output_intr (int dev)
     /*  */
 157 {
 158   /*
 159    * Currently NOP
 160    */
 161 }
 162 
 163 static void
 164 midi_poll (unsigned long dummy)
     /*  */
 165 {
 166   unsigned long   flags;
 167   int             dev;
 168 
 169   save_flags (flags);
 170   cli ();
 171   if (open_devs)
 172     {
 173       for (dev = 0; dev < num_midis; dev++)
 174         if (midi_out_buf[dev] != NULL)
 175           {
 176             while (DATA_AVAIL (midi_out_buf[dev]) &&
 177                    midi_devs[dev]->putc (dev,
 178                          midi_out_buf[dev]->queue[midi_out_buf[dev]->head]))
 179               {
 180                 midi_out_buf[dev]->head = (midi_out_buf[dev]->head + 1) % MAX_QUEUE_SIZE;
 181                 midi_out_buf[dev]->len--;
 182               }
 183 
 184             if (DATA_AVAIL (midi_out_buf[dev]) < 100 &&
 185                 (midi_sleep_flag[dev].mode & WK_SLEEP))
 186               {
 187                 midi_sleep_flag[dev].mode = WK_WAKEUP;
 188                 wake_up (&midi_sleeper[dev]);
 189               };
 190           }
 191 
 192       {
 193         poll_timer.expires = (1) + jiffies;
 194         add_timer (&poll_timer);
 195       };                        /*
 196                                    * Come back later
 197                                  */
 198     }
 199   restore_flags (flags);
 200 }
 201 
 202 int
 203 MIDIbuf_open (int dev, struct fileinfo *file)
     /*  */
 204 {
 205   int             mode, err;
 206   unsigned long   flags;
 207 
 208   dev = dev >> 4;
 209   mode = file->mode & O_ACCMODE;
 210 
 211   if (num_midis > MAX_MIDI_DEV)
 212     {
 213       printk ("Sound: FATAL ERROR: Too many midi interfaces\n");
 214       num_midis = MAX_MIDI_DEV;
 215     }
 216 
 217   if (dev < 0 || dev >= num_midis)
 218     {
 219       printk ("Sound: Nonexistent MIDI interface %d\n", dev);
 220       return -ENXIO;
 221     }
 222 
 223   /*
 224      *    Interrupts disabled. Be careful
 225    */
 226 
 227   save_flags (flags);
 228   cli ();
 229   if ((err = midi_devs[dev]->open (dev, mode,
 230                                    midi_input_intr, midi_output_intr)) < 0)
 231     {
 232       restore_flags (flags);
 233       return err;
 234     }
 235 
 236   parms[dev].prech_timeout = 0;
 237 
 238   midi_sleep_flag[dev].mode = WK_NONE;
 239   input_sleep_flag[dev].mode = WK_NONE;
 240 
 241   midi_in_buf[dev] = (struct midi_buf *) kmalloc (sizeof (struct midi_buf), GFP_KERNEL);
 242 
 243   if (midi_in_buf[dev] == NULL)
 244     {
 245       printk ("midi: Can't allocate buffer\n");
 246       midi_devs[dev]->close (dev);
 247       restore_flags (flags);
 248       return -EIO;
 249     }
 250   midi_in_buf[dev]->len = midi_in_buf[dev]->head = midi_in_buf[dev]->tail = 0;
 251 
 252   midi_out_buf[dev] = (struct midi_buf *) kmalloc (sizeof (struct midi_buf), GFP_KERNEL);
 253 
 254   if (midi_out_buf[dev] == NULL)
 255     {
 256       printk ("midi: Can't allocate buffer\n");
 257       midi_devs[dev]->close (dev);
 258       kfree (midi_in_buf[dev]);
 259       midi_in_buf[dev] = NULL;
 260       restore_flags (flags);
 261       return -EIO;
 262     }
 263   midi_out_buf[dev]->len = midi_out_buf[dev]->head = midi_out_buf[dev]->tail = 0;
 264   if (!open_devs)
 265 
 266     {
 267       poll_timer.expires = (1) + jiffies;
 268       add_timer (&poll_timer);
 269     };                          /*
 270                                    * Come back later
 271                                  */
 272   open_devs++;
 273   restore_flags (flags);
 274 
 275   return err;
 276 }
 277 
 278 void
 279 MIDIbuf_release (int dev, struct fileinfo *file)
     /*  */
 280 {
 281   int             mode;
 282   unsigned long   flags;
 283 
 284   dev = dev >> 4;
 285   mode = file->mode & O_ACCMODE;
 286 
 287   save_flags (flags);
 288   cli ();
 289 
 290   /*
 291      * Wait until the queue is empty
 292    */
 293 
 294   if (mode != OPEN_READ)
 295     {
 296       midi_devs[dev]->putc (dev, 0xfe);         /*
 297                                                    * Active sensing to shut the
 298                                                    * devices
 299                                                  */
 300 
 301       while (!(current->signal & ~current->blocked) &&
 302              DATA_AVAIL (midi_out_buf[dev]))
 303 
 304         {
 305           unsigned long   tl;
 306 
 307           if (0)
 308             current->timeout = tl = jiffies + (0);
 309           else
 310             tl = 0xffffffff;
 311           midi_sleep_flag[dev].mode = WK_SLEEP;
 312           interruptible_sleep_on (&midi_sleeper[dev]);
 313           if (!(midi_sleep_flag[dev].mode & WK_WAKEUP))
 314             {
 315               if (jiffies >= tl)
 316                 midi_sleep_flag[dev].mode |= WK_TIMEOUT;
 317             }
 318           midi_sleep_flag[dev].mode &= ~WK_SLEEP;
 319         };                      /*
 320                                    * Sync
 321                                  */
 322 
 323       drain_midi_queue (dev);   /*
 324                                  * Ensure the output queues are empty
 325                                  */
 326     }
 327 
 328   midi_devs[dev]->close (dev);
 329   kfree (midi_in_buf[dev]);
 330   kfree (midi_out_buf[dev]);
 331   midi_in_buf[dev] = NULL;
 332   midi_out_buf[dev] = NULL;
 333   open_devs--;
 334   del_timer (&poll_timer);;
 335   restore_flags (flags);
 336 }
 337 
 338 int
 339 MIDIbuf_write (int dev, struct fileinfo *file, const snd_rw_buf * buf, int count)
     /*  */
 340 {
 341   unsigned long   flags;
 342   int             c, n, i;
 343   unsigned char   tmp_data;
 344 
 345   dev = dev >> 4;
 346 
 347   if (!count)
 348     return 0;
 349 
 350   save_flags (flags);
 351   cli ();
 352 
 353   c = 0;
 354 
 355   while (c < count)
 356     {
 357       n = SPACE_AVAIL (midi_out_buf[dev]);
 358 
 359       if (n == 0)               /*
 360                                  * No space just now. We have to sleep
 361                                  */
 362         {
 363 
 364           {
 365             unsigned long   tl;
 366 
 367             if (0)
 368               current->timeout = tl = jiffies + (0);
 369             else
 370               tl = 0xffffffff;
 371             midi_sleep_flag[dev].mode = WK_SLEEP;
 372             interruptible_sleep_on (&midi_sleeper[dev]);
 373             if (!(midi_sleep_flag[dev].mode & WK_WAKEUP))
 374               {
 375                 if (jiffies >= tl)
 376                   midi_sleep_flag[dev].mode |= WK_TIMEOUT;
 377               }
 378             midi_sleep_flag[dev].mode &= ~WK_SLEEP;
 379           };
 380           if ((current->signal & ~current->blocked))
 381             {
 382               restore_flags (flags);
 383               return -EINTR;
 384             }
 385 
 386           n = SPACE_AVAIL (midi_out_buf[dev]);
 387         }
 388 
 389       if (n > (count - c))
 390         n = count - c;
 391 
 392       for (i = 0; i < n; i++)
 393         {
 394           memcpy_fromfs ((char *) &tmp_data, &((buf)[c]), 1);
 395           QUEUE_BYTE (midi_out_buf[dev], tmp_data);
 396           c++;
 397         }
 398     }
 399 
 400   restore_flags (flags);
 401 
 402   return c;
 403 }
 404 
 405 
 406 int
 407 MIDIbuf_read (int dev, struct fileinfo *file, snd_rw_buf * buf, int count)
     /*  */
 408 {
 409   int             n, c = 0;
 410   unsigned long   flags;
 411   unsigned char   tmp_data;
 412 
 413   dev = dev >> 4;
 414 
 415   save_flags (flags);
 416   cli ();
 417 
 418   if (!DATA_AVAIL (midi_in_buf[dev]))   /*
 419                                          * No data yet, wait
 420                                          */
 421     {
 422 
 423       {
 424         unsigned long   tl;
 425 
 426         if (parms[dev].prech_timeout)
 427           current->timeout = tl = jiffies + (parms[dev].prech_timeout);
 428         else
 429           tl = 0xffffffff;
 430         input_sleep_flag[dev].mode = WK_SLEEP;
 431         interruptible_sleep_on (&input_sleeper[dev]);
 432         if (!(input_sleep_flag[dev].mode & WK_WAKEUP))
 433           {
 434             if (jiffies >= tl)
 435               input_sleep_flag[dev].mode |= WK_TIMEOUT;
 436           }
 437         input_sleep_flag[dev].mode &= ~WK_SLEEP;
 438       };
 439       if ((current->signal & ~current->blocked))
 440         c = -EINTR;             /*
 441                                    * The user is getting restless
 442                                  */
 443     }
 444 
 445   if (c == 0 && DATA_AVAIL (midi_in_buf[dev]))  /*
 446                                                  * Got some bytes
 447                                                  */
 448     {
 449       n = DATA_AVAIL (midi_in_buf[dev]);
 450       if (n > count)
 451         n = count;
 452       c = 0;
 453 
 454       while (c < n)
 455         {
 456           REMOVE_BYTE (midi_in_buf[dev], tmp_data);
 457           memcpy_tofs (&((buf)[c]), (char *) &tmp_data, 1);
 458           c++;
 459         }
 460     }
 461 
 462   restore_flags (flags);
 463 
 464   return c;
 465 }
 466 
 467 int
 468 MIDIbuf_ioctl (int dev, struct fileinfo *file,
     /*  */
 469                unsigned int cmd, ioctl_arg arg)
 470 {
 471   int             val;
 472 
 473   dev = dev >> 4;
 474 
 475   if (((cmd >> 8) & 0xff) == 'C')
 476     {
 477       if (midi_devs[dev]->coproc)       /* Coprocessor ioctl */
 478         return midi_devs[dev]->coproc->ioctl (midi_devs[dev]->coproc->devc, cmd, arg, 0);
 479       else
 480         printk ("/dev/midi%d: No coprocessor for this device\n", dev);
 481 
 482       return -ENXIO;
 483     }
 484   else
 485     switch (cmd)
 486       {
 487 
 488       case SNDCTL_MIDI_PRETIME:
 489         val = (int) get_fs_long ((long *) arg);
 490         if (val < 0)
 491           val = 0;
 492 
 493         val = (HZ * val) / 10;
 494         parms[dev].prech_timeout = val;
 495         return snd_ioctl_return ((int *) arg, val);
 496         break;
 497 
 498       default:
 499         return midi_devs[dev]->ioctl (dev, cmd, arg);
 500       }
 501 }
 502 
 503 int
 504 MIDIbuf_select (int dev, struct fileinfo *file, int sel_type, select_table * wait)
     /*  */
 505 {
 506   dev = dev >> 4;
 507 
 508   switch (sel_type)
 509     {
 510     case SEL_IN:
 511       if (!DATA_AVAIL (midi_in_buf[dev]))
 512         {
 513           input_sleep_flag[dev].mode = WK_SLEEP;
 514           select_wait (&input_sleeper[dev], wait);
 515           return 0;
 516         }
 517       return 1;
 518       break;
 519 
 520     case SEL_OUT:
 521       if (SPACE_AVAIL (midi_out_buf[dev]))
 522         {
 523           midi_sleep_flag[dev].mode = WK_SLEEP;
 524           select_wait (&midi_sleeper[dev], wait);
 525           return 0;
 526         }
 527       return 1;
 528       break;
 529 
 530     case SEL_EX:
 531       return 0;
 532     }
 533 
 534   return 0;
 535 }
 536 
 537 
 538 long
 539 MIDIbuf_init (long mem_start)
     /*  */
 540 {
 541   return mem_start;
 542 }
 543 
 544 #endif
/* */
root/drivers/sound/midibuf.c

DEFINITIONS
