xref: /freebsd/sys/dev/speaker/spkr.c (revision 0c43d89a0d8e976ca494d4837f4c1f3734d2c300)
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 1.8 1994/04/21 14:21:50 sos 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/uio.h>
20 #include <i386/isa/isa.h>
21 #include <i386/isa/timerreg.h>
22 #include <machine/speaker.h>
23 
24 /**************** MACHINE DEPENDENT PART STARTS HERE *************************
25  *
26  * This section defines a function tone() which causes a tone of given
27  * frequency and duration from the 80x86's console speaker.
28  * Another function endtone() is defined to force sound off, and there is
29  * also a rest() entry point to do pauses.
30  *
31  * Audible sound is generated using the Programmable Interval Timer (PIT) and
32  * Programmable Peripheral Interface (PPI) attached to the 80x86's speaker. The
33  * PPI controls whether sound is passed through at all; the PIT's channel 2 is
34  * used to generate clicks (a square wave) of whatever frequency is desired.
35  */
36 
37 /*
38  * PIT and PPI port addresses and control values
39  *
40  * Most of the magic is hidden in the TIMER_PREP value, which selects PIT
41  * channel 2, frequency LSB first, square-wave mode and binary encoding.
42  * The encoding is as follows:
43  *
44  * +----------+----------+---------------+-----+
45  * |  1    0  |  1    1  |  0    1    1  |  0  |
46  * | SC1  SC0 | RW1  RW0 | M2   M1   M0  | BCD |
47  * +----------+----------+---------------+-----+
48  *   Counter     Write        Mode 3      Binary
49  *  Channel 2  LSB first,  (Square Wave) Encoding
50  *             MSB second
51  */
52 #define PPI_SPKR	0x03	/* turn these PPI bits on to pass sound */
53 #define PIT_MODE	0xB6	/* set timer mode for sound generation */
54 
55 /*
56  * Magic numbers for timer control.
57  */
58 #define TIMER_CLK	1193180L	/* corresponds to 18.2 MHz tick rate */
59 
60 #define SPKRPRI PSOCK
61 static char endtone, endrest;
62 
63 static void tone(thz, ticks)
64 /* emit tone of frequency thz for given number of ticks */
65 unsigned int thz, ticks;
66 {
67     unsigned int divisor = TIMER_CLK / thz;
68     int sps;
69 
70 #ifdef DEBUG
71     (void) printf("tone: thz=%d ticks=%d\n", thz, ticks);
72 #endif /* DEBUG */
73 
74     /* set timer to generate clicks at given frequency in Hertz */
75     sps = spltty();
76 
77     if (acquire_timer2(PIT_MODE)) {
78 	/* enter list of waiting procs ??? */
79 	return;
80     }
81     outb(TIMER_CNTR2, (divisor & 0xff));	/* send lo byte */
82     outb(TIMER_CNTR2, (divisor >> 8));	/* send hi byte */
83     splx(sps);
84 
85     /* turn the speaker on */
86     outb(IO_PPI, inb(IO_PPI) | PPI_SPKR);
87 
88     /*
89      * Set timeout to endtone function, then give up the timeslice.
90      * This is so other processes can execute while the tone is being
91      * emitted.
92      */
93     (void) tsleep((caddr_t)&endtone, SPKRPRI | PCATCH, "spkrtn", ticks);
94     outb(IO_PPI, inb(IO_PPI) & ~PPI_SPKR);
95     release_timer2();
96 }
97 
98 static void rest(ticks)
99 /* rest for given number of ticks */
100 int	ticks;
101 {
102     /*
103      * Set timeout to endrest function, then give up the timeslice.
104      * This is so other processes can execute while the rest is being
105      * waited out.
106      */
107 #ifdef DEBUG
108     (void) printf("rest: %d\n", ticks);
109 #endif /* DEBUG */
110     (void) tsleep((caddr_t)&endrest, SPKRPRI | PCATCH, "spkrrs", ticks);
111 }
112 
113 /**************** PLAY STRING INTERPRETER BEGINS HERE **********************
114  *
115  * Play string interpretation is modelled on IBM BASIC 2.0's PLAY statement;
116  * M[LNS] are missing; the ~ synonym and the _ slur mark and the octave-
117  * tracking facility are added.
118  * Requires tone(), rest(), and endtone(). String play is not interruptible
119  * except possibly at physical block boundaries.
120  */
121 
122 typedef int	bool;
123 #define TRUE	1
124 #define FALSE	0
125 
126 #define toupper(c)	((c) - ' ' * (((c) >= 'a') && ((c) <= 'z')))
127 #define isdigit(c)	(((c) >= '0') && ((c) <= '9'))
128 #define dtoi(c)		((c) - '0')
129 
130 static int octave;	/* currently selected octave */
131 static int whole;	/* whole-note time at current tempo, in ticks */
132 static int value;	/* whole divisor for note time, quarter note = 1 */
133 static int fill;	/* controls spacing of notes */
134 static bool octtrack;	/* octave-tracking on? */
135 static bool octprefix;	/* override current octave-tracking state? */
136 
137 /*
138  * Magic number avoidance...
139  */
140 #define SECS_PER_MIN	60	/* seconds per minute */
141 #define WHOLE_NOTE	4	/* quarter notes per whole note */
142 #define MIN_VALUE	64	/* the most we can divide a note by */
143 #define DFLT_VALUE	4	/* default value (quarter-note) */
144 #define FILLTIME	8	/* for articulation, break note in parts */
145 #define STACCATO	6	/* 6/8 = 3/4 of note is filled */
146 #define NORMAL		7	/* 7/8ths of note interval is filled */
147 #define LEGATO		8	/* all of note interval is filled */
148 #define DFLT_OCTAVE	4	/* default octave */
149 #define MIN_TEMPO	32	/* minimum tempo */
150 #define DFLT_TEMPO	120	/* default tempo */
151 #define MAX_TEMPO	255	/* max tempo */
152 #define NUM_MULT	3	/* numerator of dot multiplier */
153 #define DENOM_MULT	2	/* denominator of dot multiplier */
154 
155 /* letter to half-tone:  A   B  C  D  E  F  G */
156 static int notetab[8] = {9, 11, 0, 2, 4, 5, 7};
157 
158 /*
159  * This is the American Standard A440 Equal-Tempered scale with frequencies
160  * rounded to nearest integer. Thank Goddess for the good ol' CRC Handbook...
161  * our octave 0 is standard octave 2.
162  */
163 #define OCTAVE_NOTES	12	/* semitones per octave */
164 static int pitchtab[] =
165 {
166 /*        C     C#    D     D#    E     F     F#    G     G#    A     A#    B*/
167 /* 0 */   65,   69,   73,   78,   82,   87,   93,   98,  103,  110,  117,  123,
168 /* 1 */  131,  139,  147,  156,  165,  175,  185,  196,  208,  220,  233,  247,
169 /* 2 */  262,  277,  294,  311,  330,  349,  370,  392,  415,  440,  466,  494,
170 /* 3 */  523,  554,  587,  622,  659,  698,  740,  784,  831,  880,  932,  988,
171 /* 4 */ 1047, 1109, 1175, 1245, 1319, 1397, 1480, 1568, 1661, 1760, 1865, 1975,
172 /* 5 */ 2093, 2217, 2349, 2489, 2637, 2794, 2960, 3136, 3322, 3520, 3729, 3951,
173 /* 6 */ 4186, 4435, 4698, 4978, 5274, 5588, 5920, 6272, 6644, 7040, 7459, 7902,
174 };
175 
176 static void playinit()
177 {
178     octave = DFLT_OCTAVE;
179     whole = (hz * SECS_PER_MIN * WHOLE_NOTE) / DFLT_TEMPO;
180     fill = NORMAL;
181     value = DFLT_VALUE;
182     octtrack = FALSE;
183     octprefix = TRUE;	/* act as though there was an initial O(n) */
184 }
185 
186 static void playtone(pitch, value, sustain)
187 /* play tone of proper duration for current rhythm signature */
188 int	pitch, value, sustain;
189 {
190     register int	sound, silence, snum = 1, sdenom = 1;
191 
192     /* this weirdness avoids floating-point arithmetic */
193     for (; sustain; sustain--)
194     {
195 	/* See the BUGS section in the man page for discussion */
196 	snum *= NUM_MULT;
197 	sdenom *= DENOM_MULT;
198     }
199 
200     if (pitch == -1)
201 	rest(whole * snum / (value * sdenom));
202     else
203     {
204 	sound = (whole * snum) / (value * sdenom)
205 		- (whole * (FILLTIME - fill)) / (value * FILLTIME);
206 	silence = whole * (FILLTIME-fill) * snum / (FILLTIME * value * sdenom);
207 
208 #ifdef DEBUG
209 	(void) printf("playtone: pitch %d for %d ticks, rest for %d ticks\n",
210 			pitch, sound, silence);
211 #endif /* DEBUG */
212 
213 	tone(pitchtab[pitch], sound);
214 	if (fill != LEGATO)
215 	    rest(silence);
216     }
217 }
218 
219 static int abs(n)
220 int n;
221 {
222     if (n < 0)
223 	return(-n);
224     else
225 	return(n);
226 }
227 
228 static void playstring(cp, slen)
229 /* interpret and play an item from a notation string */
230 char	*cp;
231 size_t	slen;
232 {
233     int		pitch, oldfill, lastpitch = OCTAVE_NOTES * DFLT_OCTAVE;
234 
235 #define GETNUM(cp, v)	for(v=0; isdigit(cp[1]) && slen > 0; ) \
236 				{v = v * 10 + (*++cp - '0'); slen--;}
237     for (; slen--; cp++)
238     {
239 	int		sustain, timeval, tempo;
240 	register char	c = toupper(*cp);
241 
242 #ifdef DEBUG
243 	(void) printf("playstring: %c (%x)\n", c, c);
244 #endif /* DEBUG */
245 
246 	switch (c)
247 	{
248 	case 'A':  case 'B': case 'C': case 'D': case 'E': case 'F': case 'G':
249 
250 	    /* compute pitch */
251 	    pitch = notetab[c - 'A'] + octave * OCTAVE_NOTES;
252 
253 	    /* this may be followed by an accidental sign */
254 	    if (cp[1] == '#' || cp[1] == '+')
255 	    {
256 		++pitch;
257 		++cp;
258 		slen--;
259 	    }
260 	    else if (cp[1] == '-')
261 	    {
262 		--pitch;
263 		++cp;
264 		slen--;
265 	    }
266 
267 	    /*
268 	     * If octave-tracking mode is on, and there has been no octave-
269 	     * setting prefix, find the version of the current letter note
270 	     * closest to the last regardless of octave.
271 	     */
272 	    if (octtrack && !octprefix)
273 	    {
274 		if (abs(pitch-lastpitch) > abs(pitch+OCTAVE_NOTES-lastpitch))
275 		{
276 		    ++octave;
277 		    pitch += OCTAVE_NOTES;
278 		}
279 
280 		if (abs(pitch-lastpitch) > abs((pitch-OCTAVE_NOTES)-lastpitch))
281 		{
282 		    --octave;
283 		    pitch -= OCTAVE_NOTES;
284 		}
285 	    }
286 	    octprefix = FALSE;
287 	    lastpitch = pitch;
288 
289 	    /* ...which may in turn be followed by an override time value */
290 	    GETNUM(cp, timeval);
291 	    if (timeval <= 0 || timeval > MIN_VALUE)
292 		timeval = value;
293 
294 	    /* ...and/or sustain dots */
295 	    for (sustain = 0; cp[1] == '.'; cp++)
296 	    {
297 		slen--;
298 		sustain++;
299 	    }
300 
301 	    /* ...and/or a slur mark */
302 	    oldfill = fill;
303 	    if (cp[1] == '_')
304 	    {
305 		fill = LEGATO;
306 		++cp;
307 		slen--;
308 	    }
309 
310 	    /* time to emit the actual tone */
311 	    playtone(pitch, timeval, sustain);
312 
313 	    fill = oldfill;
314 	    break;
315 
316 	case 'O':
317 	    if (cp[1] == 'N' || cp[1] == 'n')
318 	    {
319 		octprefix = octtrack = FALSE;
320 		++cp;
321 		slen--;
322 	    }
323 	    else if (cp[1] == 'L' || cp[1] == 'l')
324 	    {
325 		octtrack = TRUE;
326 		++cp;
327 		slen--;
328 	    }
329 	    else
330 	    {
331 		GETNUM(cp, octave);
332 		if (octave >= sizeof(pitchtab) / OCTAVE_NOTES)
333 		    octave = DFLT_OCTAVE;
334 		octprefix = TRUE;
335 	    }
336 	    break;
337 
338 	case '>':
339 	    if (octave < sizeof(pitchtab) / OCTAVE_NOTES - 1)
340 		octave++;
341 	    octprefix = TRUE;
342 	    break;
343 
344 	case '<':
345 	    if (octave > 0)
346 		octave--;
347 	    octprefix = TRUE;
348 	    break;
349 
350 	case 'N':
351 	    GETNUM(cp, pitch);
352 	    for (sustain = 0; cp[1] == '.'; cp++)
353 	    {
354 		slen--;
355 		sustain++;
356 	    }
357 	    oldfill = fill;
358 	    if (cp[1] == '_')
359 	    {
360 		fill = LEGATO;
361 		++cp;
362 		slen--;
363 	    }
364 	    playtone(pitch - 1, value, sustain);
365 	    fill = oldfill;
366 	    break;
367 
368 	case 'L':
369 	    GETNUM(cp, value);
370 	    if (value <= 0 || value > MIN_VALUE)
371 		value = DFLT_VALUE;
372 	    break;
373 
374 	case 'P':
375 	case '~':
376 	    /* this may be followed by an override time value */
377 	    GETNUM(cp, timeval);
378 	    if (timeval <= 0 || timeval > MIN_VALUE)
379 		timeval = value;
380 	    for (sustain = 0; cp[1] == '.'; cp++)
381 	    {
382 		slen--;
383 		sustain++;
384 	    }
385 	    playtone(-1, timeval, sustain);
386 	    break;
387 
388 	case 'T':
389 	    GETNUM(cp, tempo);
390 	    if (tempo < MIN_TEMPO || tempo > MAX_TEMPO)
391 		tempo = DFLT_TEMPO;
392 	    whole = (hz * SECS_PER_MIN * WHOLE_NOTE) / tempo;
393 	    break;
394 
395 	case 'M':
396 	    if (cp[1] == 'N' || cp[1] == 'n')
397 	    {
398 		fill = NORMAL;
399 		++cp;
400 		slen--;
401 	    }
402 	    else if (cp[1] == 'L' || cp[1] == 'l')
403 	    {
404 		fill = LEGATO;
405 		++cp;
406 		slen--;
407 	    }
408 	    else if (cp[1] == 'S' || cp[1] == 's')
409 	    {
410 		fill = STACCATO;
411 		++cp;
412 		slen--;
413 	    }
414 	    break;
415 	}
416     }
417 }
418 
419 /******************* UNIX DRIVER HOOKS BEGIN HERE **************************
420  *
421  * This section implements driver hooks to run playstring() and the tone(),
422  * endtone(), and rest() functions defined above.
423  */
424 
425 static int spkr_active = FALSE; /* exclusion flag */
426 static struct buf *spkr_inbuf;  /* incoming buf */
427 
428 int spkropen(dev)
429 dev_t	dev;
430 {
431 #ifdef DEBUG
432     (void) printf("spkropen: entering with dev = %x\n", dev);
433 #endif /* DEBUG */
434 
435     if (minor(dev) != 0)
436 	return(ENXIO);
437     else if (spkr_active)
438 	return(EBUSY);
439     else
440     {
441 #ifdef DEBUG
442 	(void) printf("spkropen: about to perform play initialization\n");
443 #endif /* DEBUG */
444 	playinit();
445 	spkr_inbuf = geteblk(DEV_BSIZE);
446 	spkr_active = TRUE;
447 	return(0);
448     }
449 }
450 
451 int spkrwrite(dev, uio)
452 dev_t		dev;
453 struct uio	*uio;
454 {
455 #ifdef DEBUG
456     printf("spkrwrite: entering with dev = %x, count = %d\n",
457 		dev, uio->uio_resid);
458 #endif /* DEBUG */
459 
460     if (minor(dev) != 0)
461 	return(ENXIO);
462     else if (uio->uio_resid > DEV_BSIZE)     /* prevent system crashes */
463 	return(E2BIG);
464     else
465     {
466 	unsigned n;
467 	char *cp;
468 	int error;
469 
470 	n = uio->uio_resid;
471 	cp = spkr_inbuf->b_un.b_addr;
472 	if (!(error = uiomove(cp, n, uio)))
473 		playstring(cp, n);
474 	return(error);
475     }
476 }
477 
478 int spkrclose(dev)
479 dev_t	dev;
480 {
481 #ifdef DEBUG
482     (void) printf("spkrclose: entering with dev = %x\n", dev);
483 #endif /* DEBUG */
484 
485     if (minor(dev) != 0)
486 	return(ENXIO);
487     else
488     {
489 	wakeup((caddr_t)&endtone);
490 	wakeup((caddr_t)&endrest);
491 	brelse(spkr_inbuf);
492 	spkr_active = FALSE;
493 	return(0);
494     }
495 }
496 
497 int spkrioctl(dev, cmd, cmdarg)
498 dev_t	dev;
499 int	cmd;
500 caddr_t	cmdarg;
501 {
502 #ifdef DEBUG
503     (void) printf("spkrioctl: entering with dev = %x, cmd = %x\n");
504 #endif /* DEBUG */
505 
506     if (minor(dev) != 0)
507 	return(ENXIO);
508     else if (cmd == SPKRTONE)
509     {
510 	tone_t	*tp = (tone_t *)cmdarg;
511 
512 	if (tp->frequency == 0)
513 	    rest(tp->duration);
514 	else
515 	    tone(tp->frequency, tp->duration);
516 	return 0;
517     }
518     else if (cmd == SPKRTUNE)
519     {
520 	tone_t  *tp = (tone_t *)(*(caddr_t *)cmdarg);
521 	tone_t ttp;
522 	int error;
523 
524 	for (; ; tp++) {
525 	    error = copyin(tp, &ttp, sizeof(tone_t));
526 	    if (error)
527 		    return(error);
528 	    if (ttp.duration == 0)
529 		    break;
530 	    if (ttp.frequency == 0)
531 		 rest(ttp.duration);
532 	    else
533 		 tone(ttp.frequency, ttp.duration);
534 	}
535 	return(0);
536     }
537     return(EINVAL);
538 }
539 
540 #endif  /* NSPEAKER > 0 */
541 /* spkr.c ends here */
542