xref: /freebsd/sys/dev/speaker/spkr.c (revision 5ebc7e6281887681c3a348a5a4c902e262ccd656)
1 /*
2  * spkr.c -- device driver for console speaker
3  *
4  * v1.4 by Eric S. Raymond (esr@snark.thyrsus.com) Aug 1993
5  * modified for FreeBSD by Andrew A. Chernov <ache@astral.msk.su>
6  *
7  *    $Id: spkr.c,v 1.12 1995/03/16 18:12:05 bde Exp $
8  */
9 
10 #include "speaker.h"
11 
12 #if NSPEAKER > 0
13 
14 #include <sys/param.h>
15 #include <sys/systm.h>
16 #include <sys/kernel.h>
17 #include <sys/errno.h>
18 #include <sys/buf.h>
19 #include <sys/proc.h>
20 #include <sys/uio.h>
21 #include <i386/isa/isa.h>
22 #include <i386/isa/timerreg.h>
23 #include <machine/clock.h>
24 #include <machine/speaker.h>
25 
26 /**************** MACHINE DEPENDENT PART STARTS HERE *************************
27  *
28  * This section defines a function tone() which causes a tone of given
29  * frequency and duration from the 80x86's console speaker.
30  * Another function endtone() is defined to force sound off, and there is
31  * also a rest() entry point to do pauses.
32  *
33  * Audible sound is generated using the Programmable Interval Timer (PIT) and
34  * Programmable Peripheral Interface (PPI) attached to the 80x86's speaker. The
35  * PPI controls whether sound is passed through at all; the PIT's channel 2 is
36  * used to generate clicks (a square wave) of whatever frequency is desired.
37  */
38 
39 /*
40  * PIT and PPI port addresses and control values
41  *
42  * Most of the magic is hidden in the TIMER_PREP value, which selects PIT
43  * channel 2, frequency LSB first, square-wave mode and binary encoding.
44  * The encoding is as follows:
45  *
46  * +----------+----------+---------------+-----+
47  * |  1    0  |  1    1  |  0    1    1  |  0  |
48  * | SC1  SC0 | RW1  RW0 | M2   M1   M0  | BCD |
49  * +----------+----------+---------------+-----+
50  *   Counter     Write        Mode 3      Binary
51  *  Channel 2  LSB first,  (Square Wave) Encoding
52  *             MSB second
53  */
54 #define PPI_SPKR	0x03	/* turn these PPI bits on to pass sound */
55 #define PIT_MODE	0xB6	/* set timer mode for sound generation */
56 
57 /*
58  * Magic numbers for timer control.
59  */
60 #define TIMER_CLK	1193180L	/* corresponds to 18.2 MHz tick rate */
61 
62 #define SPKRPRI PSOCK
63 static char endtone, endrest;
64 
65 static void tone(thz, ticks)
66 /* emit tone of frequency thz for given number of ticks */
67 unsigned int thz, ticks;
68 {
69     unsigned int divisor;
70     int sps;
71 
72     if (thz <= 0)
73 	return;
74 
75     divisor = TIMER_CLK / thz;
76 
77 #ifdef DEBUG
78     (void) printf("tone: thz=%d ticks=%d\n", thz, ticks);
79 #endif /* DEBUG */
80 
81     /* set timer to generate clicks at given frequency in Hertz */
82     sps = spltty();
83 
84     if (acquire_timer2(PIT_MODE)) {
85 	/* enter list of waiting procs ??? */
86 	return;
87     }
88     outb(TIMER_CNTR2, (divisor & 0xff));	/* send lo byte */
89     outb(TIMER_CNTR2, (divisor >> 8));	/* send hi byte */
90     splx(sps);
91 
92     /* turn the speaker on */
93     outb(IO_PPI, inb(IO_PPI) | PPI_SPKR);
94 
95     /*
96      * Set timeout to endtone function, then give up the timeslice.
97      * This is so other processes can execute while the tone is being
98      * emitted.
99      */
100     if (ticks > 0)
101 	tsleep((caddr_t)&endtone, SPKRPRI | PCATCH, "spkrtn", ticks);
102     outb(IO_PPI, inb(IO_PPI) & ~PPI_SPKR);
103     release_timer2();
104 }
105 
106 static void rest(ticks)
107 /* rest for given number of ticks */
108 int	ticks;
109 {
110     /*
111      * Set timeout to endrest function, then give up the timeslice.
112      * This is so other processes can execute while the rest is being
113      * waited out.
114      */
115 #ifdef DEBUG
116     (void) printf("rest: %d\n", ticks);
117 #endif /* DEBUG */
118     if (ticks > 0)
119 	tsleep((caddr_t)&endrest, SPKRPRI | PCATCH, "spkrrs", ticks);
120 }
121 
122 /**************** PLAY STRING INTERPRETER BEGINS HERE **********************
123  *
124  * Play string interpretation is modelled on IBM BASIC 2.0's PLAY statement;
125  * M[LNS] are missing; the ~ synonym and the _ slur mark and the octave-
126  * tracking facility are added.
127  * Requires tone(), rest(), and endtone(). String play is not interruptible
128  * except possibly at physical block boundaries.
129  */
130 
131 typedef int	bool;
132 #define TRUE	1
133 #define FALSE	0
134 
135 #define toupper(c)	((c) - ' ' * (((c) >= 'a') && ((c) <= 'z')))
136 #define isdigit(c)	(((c) >= '0') && ((c) <= '9'))
137 #define dtoi(c)		((c) - '0')
138 
139 static int octave;	/* currently selected octave */
140 static int whole;	/* whole-note time at current tempo, in ticks */
141 static int value;	/* whole divisor for note time, quarter note = 1 */
142 static int fill;	/* controls spacing of notes */
143 static bool octtrack;	/* octave-tracking on? */
144 static bool octprefix;	/* override current octave-tracking state? */
145 
146 /*
147  * Magic number avoidance...
148  */
149 #define SECS_PER_MIN	60	/* seconds per minute */
150 #define WHOLE_NOTE	4	/* quarter notes per whole note */
151 #define MIN_VALUE	64	/* the most we can divide a note by */
152 #define DFLT_VALUE	4	/* default value (quarter-note) */
153 #define FILLTIME	8	/* for articulation, break note in parts */
154 #define STACCATO	6	/* 6/8 = 3/4 of note is filled */
155 #define NORMAL		7	/* 7/8ths of note interval is filled */
156 #define LEGATO		8	/* all of note interval is filled */
157 #define DFLT_OCTAVE	4	/* default octave */
158 #define MIN_TEMPO	32	/* minimum tempo */
159 #define DFLT_TEMPO	120	/* default tempo */
160 #define MAX_TEMPO	255	/* max tempo */
161 #define NUM_MULT	3	/* numerator of dot multiplier */
162 #define DENOM_MULT	2	/* denominator of dot multiplier */
163 
164 /* letter to half-tone:  A   B  C  D  E  F  G */
165 static int notetab[8] = {9, 11, 0, 2, 4, 5, 7};
166 
167 /*
168  * This is the American Standard A440 Equal-Tempered scale with frequencies
169  * rounded to nearest integer. Thank Goddess for the good ol' CRC Handbook...
170  * our octave 0 is standard octave 2.
171  */
172 #define OCTAVE_NOTES	12	/* semitones per octave */
173 static int pitchtab[] =
174 {
175 /*        C     C#    D     D#    E     F     F#    G     G#    A     A#    B*/
176 /* 0 */   65,   69,   73,   78,   82,   87,   93,   98,  103,  110,  117,  123,
177 /* 1 */  131,  139,  147,  156,  165,  175,  185,  196,  208,  220,  233,  247,
178 /* 2 */  262,  277,  294,  311,  330,  349,  370,  392,  415,  440,  466,  494,
179 /* 3 */  523,  554,  587,  622,  659,  698,  740,  784,  831,  880,  932,  988,
180 /* 4 */ 1047, 1109, 1175, 1245, 1319, 1397, 1480, 1568, 1661, 1760, 1865, 1975,
181 /* 5 */ 2093, 2217, 2349, 2489, 2637, 2794, 2960, 3136, 3322, 3520, 3729, 3951,
182 /* 6 */ 4186, 4435, 4698, 4978, 5274, 5588, 5920, 6272, 6644, 7040, 7459, 7902,
183 };
184 
185 static void playinit()
186 {
187     octave = DFLT_OCTAVE;
188     whole = (hz * SECS_PER_MIN * WHOLE_NOTE) / DFLT_TEMPO;
189     fill = NORMAL;
190     value = DFLT_VALUE;
191     octtrack = FALSE;
192     octprefix = TRUE;	/* act as though there was an initial O(n) */
193 }
194 
195 static void playtone(pitch, value, sustain)
196 /* play tone of proper duration for current rhythm signature */
197 int	pitch, value, sustain;
198 {
199     register int	sound, silence, snum = 1, sdenom = 1;
200 
201     /* this weirdness avoids floating-point arithmetic */
202     for (; sustain; sustain--)
203     {
204 	/* See the BUGS section in the man page for discussion */
205 	snum *= NUM_MULT;
206 	sdenom *= DENOM_MULT;
207     }
208 
209     if (value == 0 || sdenom == 0)
210 	return;
211 
212     if (pitch == -1)
213 	rest(whole * snum / (value * sdenom));
214     else
215     {
216 	sound = (whole * snum) / (value * sdenom)
217 		- (whole * (FILLTIME - fill)) / (value * FILLTIME);
218 	silence = whole * (FILLTIME-fill) * snum / (FILLTIME * value * sdenom);
219 
220 #ifdef DEBUG
221 	(void) printf("playtone: pitch %d for %d ticks, rest for %d ticks\n",
222 			pitch, sound, silence);
223 #endif /* DEBUG */
224 
225 	tone(pitchtab[pitch], sound);
226 	if (fill != LEGATO)
227 	    rest(silence);
228     }
229 }
230 
231 static int abs(n)
232 int n;
233 {
234     if (n < 0)
235 	return(-n);
236     else
237 	return(n);
238 }
239 
240 static void playstring(cp, slen)
241 /* interpret and play an item from a notation string */
242 char	*cp;
243 size_t	slen;
244 {
245     int		pitch, oldfill, lastpitch = OCTAVE_NOTES * DFLT_OCTAVE;
246 
247 #define GETNUM(cp, v)	for(v=0; isdigit(cp[1]) && slen > 0; ) \
248 				{v = v * 10 + (*++cp - '0'); slen--;}
249     for (; slen--; cp++)
250     {
251 	int		sustain, timeval, tempo;
252 	register char	c = toupper(*cp);
253 
254 #ifdef DEBUG
255 	(void) printf("playstring: %c (%x)\n", c, c);
256 #endif /* DEBUG */
257 
258 	switch (c)
259 	{
260 	case 'A':  case 'B': case 'C': case 'D': case 'E': case 'F': case 'G':
261 
262 	    /* compute pitch */
263 	    pitch = notetab[c - 'A'] + octave * OCTAVE_NOTES;
264 
265 	    /* this may be followed by an accidental sign */
266 	    if (cp[1] == '#' || cp[1] == '+')
267 	    {
268 		++pitch;
269 		++cp;
270 		slen--;
271 	    }
272 	    else if (cp[1] == '-')
273 	    {
274 		--pitch;
275 		++cp;
276 		slen--;
277 	    }
278 
279 	    /*
280 	     * If octave-tracking mode is on, and there has been no octave-
281 	     * setting prefix, find the version of the current letter note
282 	     * closest to the last regardless of octave.
283 	     */
284 	    if (octtrack && !octprefix)
285 	    {
286 		if (abs(pitch-lastpitch) > abs(pitch+OCTAVE_NOTES-lastpitch))
287 		{
288 		    ++octave;
289 		    pitch += OCTAVE_NOTES;
290 		}
291 
292 		if (abs(pitch-lastpitch) > abs((pitch-OCTAVE_NOTES)-lastpitch))
293 		{
294 		    --octave;
295 		    pitch -= OCTAVE_NOTES;
296 		}
297 	    }
298 	    octprefix = FALSE;
299 	    lastpitch = pitch;
300 
301 	    /* ...which may in turn be followed by an override time value */
302 	    GETNUM(cp, timeval);
303 	    if (timeval <= 0 || timeval > MIN_VALUE)
304 		timeval = value;
305 
306 	    /* ...and/or sustain dots */
307 	    for (sustain = 0; cp[1] == '.'; cp++)
308 	    {
309 		slen--;
310 		sustain++;
311 	    }
312 
313 	    /* ...and/or a slur mark */
314 	    oldfill = fill;
315 	    if (cp[1] == '_')
316 	    {
317 		fill = LEGATO;
318 		++cp;
319 		slen--;
320 	    }
321 
322 	    /* time to emit the actual tone */
323 	    playtone(pitch, timeval, sustain);
324 
325 	    fill = oldfill;
326 	    break;
327 
328 	case 'O':
329 	    if (cp[1] == 'N' || cp[1] == 'n')
330 	    {
331 		octprefix = octtrack = FALSE;
332 		++cp;
333 		slen--;
334 	    }
335 	    else if (cp[1] == 'L' || cp[1] == 'l')
336 	    {
337 		octtrack = TRUE;
338 		++cp;
339 		slen--;
340 	    }
341 	    else
342 	    {
343 		GETNUM(cp, octave);
344 		if (octave >= sizeof(pitchtab) / sizeof(pitchtab[0]) / OCTAVE_NOTES)
345 		    octave = DFLT_OCTAVE;
346 		octprefix = TRUE;
347 	    }
348 	    break;
349 
350 	case '>':
351 	    if (octave < sizeof(pitchtab) / sizeof(pitchtab[0]) / OCTAVE_NOTES - 1)
352 		octave++;
353 	    octprefix = TRUE;
354 	    break;
355 
356 	case '<':
357 	    if (octave > 0)
358 		octave--;
359 	    octprefix = TRUE;
360 	    break;
361 
362 	case 'N':
363 	    GETNUM(cp, pitch);
364 	    for (sustain = 0; cp[1] == '.'; cp++)
365 	    {
366 		slen--;
367 		sustain++;
368 	    }
369 	    oldfill = fill;
370 	    if (cp[1] == '_')
371 	    {
372 		fill = LEGATO;
373 		++cp;
374 		slen--;
375 	    }
376 	    playtone(pitch - 1, value, sustain);
377 	    fill = oldfill;
378 	    break;
379 
380 	case 'L':
381 	    GETNUM(cp, value);
382 	    if (value <= 0 || value > MIN_VALUE)
383 		value = DFLT_VALUE;
384 	    break;
385 
386 	case 'P':
387 	case '~':
388 	    /* this may be followed by an override time value */
389 	    GETNUM(cp, timeval);
390 	    if (timeval <= 0 || timeval > MIN_VALUE)
391 		timeval = value;
392 	    for (sustain = 0; cp[1] == '.'; cp++)
393 	    {
394 		slen--;
395 		sustain++;
396 	    }
397 	    playtone(-1, timeval, sustain);
398 	    break;
399 
400 	case 'T':
401 	    GETNUM(cp, tempo);
402 	    if (tempo < MIN_TEMPO || tempo > MAX_TEMPO)
403 		tempo = DFLT_TEMPO;
404 	    whole = (hz * SECS_PER_MIN * WHOLE_NOTE) / tempo;
405 	    break;
406 
407 	case 'M':
408 	    if (cp[1] == 'N' || cp[1] == 'n')
409 	    {
410 		fill = NORMAL;
411 		++cp;
412 		slen--;
413 	    }
414 	    else if (cp[1] == 'L' || cp[1] == 'l')
415 	    {
416 		fill = LEGATO;
417 		++cp;
418 		slen--;
419 	    }
420 	    else if (cp[1] == 'S' || cp[1] == 's')
421 	    {
422 		fill = STACCATO;
423 		++cp;
424 		slen--;
425 	    }
426 	    break;
427 	}
428     }
429 }
430 
431 /******************* UNIX DRIVER HOOKS BEGIN HERE **************************
432  *
433  * This section implements driver hooks to run playstring() and the tone(),
434  * endtone(), and rest() functions defined above.
435  */
436 
437 static int spkr_active = FALSE; /* exclusion flag */
438 static struct buf *spkr_inbuf;  /* incoming buf */
439 
440 int spkropen(dev)
441 dev_t	dev;
442 {
443 #ifdef DEBUG
444     (void) printf("spkropen: entering with dev = %x\n", dev);
445 #endif /* DEBUG */
446 
447     if (minor(dev) != 0)
448 	return(ENXIO);
449     else if (spkr_active)
450 	return(EBUSY);
451     else
452     {
453 #ifdef DEBUG
454 	(void) printf("spkropen: about to perform play initialization\n");
455 #endif /* DEBUG */
456 	playinit();
457 	spkr_inbuf = geteblk(DEV_BSIZE);
458 	spkr_active = TRUE;
459 	return(0);
460     }
461 }
462 
463 int spkrwrite(dev, uio)
464 dev_t		dev;
465 struct uio	*uio;
466 {
467 #ifdef DEBUG
468     printf("spkrwrite: entering with dev = %x, count = %d\n",
469 		dev, uio->uio_resid);
470 #endif /* DEBUG */
471 
472     if (minor(dev) != 0)
473 	return(ENXIO);
474     else if (uio->uio_resid > DEV_BSIZE)     /* prevent system crashes */
475 	return(E2BIG);
476     else
477     {
478 	unsigned n;
479 	char *cp;
480 	int error;
481 
482 	n = uio->uio_resid;
483 	cp = spkr_inbuf->b_un.b_addr;
484 	if (!(error = uiomove(cp, n, uio)))
485 		playstring(cp, n);
486 	return(error);
487     }
488 }
489 
490 int spkrclose(dev)
491 dev_t	dev;
492 {
493 #ifdef DEBUG
494     (void) printf("spkrclose: entering with dev = %x\n", dev);
495 #endif /* DEBUG */
496 
497     if (minor(dev) != 0)
498 	return(ENXIO);
499     else
500     {
501 	wakeup((caddr_t)&endtone);
502 	wakeup((caddr_t)&endrest);
503 	brelse(spkr_inbuf);
504 	spkr_active = FALSE;
505 	return(0);
506     }
507 }
508 
509 int spkrioctl(dev, cmd, cmdarg)
510 dev_t	dev;
511 int	cmd;
512 caddr_t	cmdarg;
513 {
514 #ifdef DEBUG
515     (void) printf("spkrioctl: entering with dev = %x, cmd = %x\n");
516 #endif /* DEBUG */
517 
518     if (minor(dev) != 0)
519 	return(ENXIO);
520     else if (cmd == SPKRTONE)
521     {
522 	tone_t	*tp = (tone_t *)cmdarg;
523 
524 	if (tp->frequency == 0)
525 	    rest(tp->duration);
526 	else
527 	    tone(tp->frequency, tp->duration);
528 	return 0;
529     }
530     else if (cmd == SPKRTUNE)
531     {
532 	tone_t  *tp = (tone_t *)(*(caddr_t *)cmdarg);
533 	tone_t ttp;
534 	int error;
535 
536 	for (; ; tp++) {
537 	    error = copyin(tp, &ttp, sizeof(tone_t));
538 	    if (error)
539 		    return(error);
540 	    if (ttp.duration == 0)
541 		    break;
542 	    if (ttp.frequency == 0)
543 		 rest(ttp.duration);
544 	    else
545 		 tone(ttp.frequency, ttp.duration);
546 	}
547 	return(0);
548     }
549     return(EINVAL);
550 }
551 
552 #endif  /* NSPEAKER > 0 */
553 /* spkr.c ends here */
554