1 /*
2  *  linux/sound/oss/dmasound/dmasound_core.c
3  *
4  *
5  *  OSS/Free compatible Atari TT/Falcon and Amiga DMA sound driver for
6  *  Linux/m68k
7  *  Extended to support Power Macintosh for Linux/ppc by Paul Mackerras
8  *
9  *  (c) 1995 by Michael Schlueter & Michael Marte
10  *
11  *  Michael Schlueter (michael@duck.syd.de) did the basic structure of the VFS
12  *  interface and the u-law to signed byte conversion.
13  *
14  *  Michael Marte (marte@informatik.uni-muenchen.de) did the sound queue,
15  *  /dev/mixer, /dev/sndstat and complemented the VFS interface. He would like
16  *  to thank:
17  *    - Michael Schlueter for initial ideas and documentation on the MFP and
18  *	the DMA sound hardware.
19  *    - Therapy? for their CD 'Troublegum' which really made me rock.
20  *
21  *  /dev/sndstat is based on code by Hannu Savolainen, the author of the
22  *  VoxWare family of drivers.
23  *
24  *  This file is subject to the terms and conditions of the GNU General Public
25  *  License.  See the file COPYING in the main directory of this archive
26  *  for more details.
27  *
28  *  History:
29  *
30  *	1995/8/25	First release
31  *
32  *	1995/9/02	Roman Hodek:
33  *			  - Fixed atari_stram_alloc() call, the timer
34  *			    programming and several race conditions
35  *	1995/9/14	Roman Hodek:
36  *			  - After some discussion with Michael Schlueter,
37  *			    revised the interrupt disabling
38  *			  - Slightly speeded up U8->S8 translation by using
39  *			    long operations where possible
40  *			  - Added 4:3 interpolation for /dev/audio
41  *
42  *	1995/9/20	Torsten Scherer:
43  *			  - Fixed a bug in sq_write and changed /dev/audio
44  *			    converting to play at 12517Hz instead of 6258Hz.
45  *
46  *	1995/9/23	Torsten Scherer:
47  *			  - Changed sq_interrupt() and sq_play() to pre-program
48  *			    the DMA for another frame while there's still one
49  *			    running. This allows the IRQ response to be
50  *			    arbitrarily delayed and playing will still continue.
51  *
52  *	1995/10/14	Guenther Kelleter, Torsten Scherer:
53  *			  - Better support for Falcon audio (the Falcon doesn't
54  *			    raise an IRQ at the end of a frame, but at the
55  *			    beginning instead!). uses 'if (codec_dma)' in lots
56  *			    of places to simply switch between Falcon and TT
57  *			    code.
58  *
59  *	1995/11/06	Torsten Scherer:
60  *			  - Started introducing a hardware abstraction scheme
61  *			    (may perhaps also serve for Amigas?)
62  *			  - Can now play samples at almost all frequencies by
63  *			    means of a more generalized expand routine
64  *			  - Takes a good deal of care to cut data only at
65  *			    sample sizes
66  *			  - Buffer size is now a kernel runtime option
67  *			  - Implemented fsync() & several minor improvements
68  *			Guenther Kelleter:
69  *			  - Useful hints and bug fixes
70  *			  - Cross-checked it for Falcons
71  *
72  *	1996/3/9	Geert Uytterhoeven:
73  *			  - Support added for Amiga, A-law, 16-bit little
74  *			    endian.
75  *			  - Unification to drivers/sound/dmasound.c.
76  *
77  *	1996/4/6	Martin Mitchell:
78  *			  - Updated to 1.3 kernel.
79  *
80  *	1996/6/13       Topi Kanerva:
81  *			  - Fixed things that were broken (mainly the amiga
82  *			    14-bit routines)
83  *			  - /dev/sndstat shows now the real hardware frequency
84  *			  - The lowpass filter is disabled by default now
85  *
86  *	1996/9/25	Geert Uytterhoeven:
87  *			  - Modularization
88  *
89  *	1998/6/10	Andreas Schwab:
90  *			  - Converted to use sound_core
91  *
92  *	1999/12/28	Richard Zidlicky:
93  *			  - Added support for Q40
94  *
95  *	2000/2/27	Geert Uytterhoeven:
96  *			  - Clean up and split the code into 4 parts:
97  *			      o dmasound_core: machine-independent code
98  *			      o dmasound_atari: Atari TT and Falcon support
99  *			      o dmasound_awacs: Apple PowerMac support
100  *			      o dmasound_paula: Amiga support
101  *
102  *	2000/3/25	Geert Uytterhoeven:
103  *			  - Integration of dmasound_q40
104  *			  - Small clean ups
105  *
106  *	2001/01/26 [1.0] Iain Sandoe
107  *			  - make /dev/sndstat show revision & edition info.
108  *			  - since dmasound.mach.sq_setup() can fail on pmac
109  *			    its type has been changed to int and the returns
110  *			    are checked.
111  *		   [1.1]  - stop missing translations from being called.
112  *	2001/02/08 [1.2]  - remove unused translation tables & move machine-
113  *			    specific tables to low-level.
114  *			  - return correct info. for SNDCTL_DSP_GETFMTS.
115  *		   [1.3]  - implement SNDCTL_DSP_GETCAPS fully.
116  *		   [1.4]  - make /dev/sndstat text length usage deterministic.
117  *			  - make /dev/sndstat call to low-level
118  *			    dmasound.mach.state_info() pass max space to ll driver.
119  *			  - tidy startup banners and output info.
120  *		   [1.5]  - tidy up a little (removed some unused #defines in
121  *			    dmasound.h)
122  *			  - fix up HAS_RECORD conditionalisation.
123  *			  - add record code in places it is missing...
124  *			  - change buf-sizes to bytes to allow < 1kb for pmac
125  *			    if user param entry is < 256 the value is taken to
126  *			    be in kb > 256 is taken to be in bytes.
127  *			  - make default buff/frag params conditional on
128  *			    machine to allow smaller values for pmac.
129  *			  - made the ioctls, read & write comply with the OSS
130  *			    rules on setting params.
131  *			  - added parsing of _setup() params for record.
132  *	2001/04/04 [1.6]  - fix bug where sample rates higher than maximum were
133  *			    being reported as OK.
134  *			  - fix open() to return -EBUSY as per OSS doc. when
135  *			    audio is in use - this is independent of O_NOBLOCK.
136  *			  - fix bug where SNDCTL_DSP_POST was blocking.
137  */
138 
139  /* Record capability notes 30/01/2001:
140   * At present these observations apply only to pmac LL driver (the only one
141   * that can do record, at present).  However, if other LL drivers for machines
142   * with record are added they may apply.
143   *
144   * The fragment parameters for the record and play channels are separate.
145   * However, if the driver is opened O_RDWR there is no way (in the current OSS
146   * API) to specify their values independently for the record and playback
147   * channels.  Since the only common factor between the input & output is the
148   * sample rate (on pmac) it should be possible to open /dev/dspX O_WRONLY and
149   * /dev/dspY O_RDONLY.  The input & output channels could then have different
150   * characteristics (other than the first that sets sample rate claiming the
151   * right to set it for ever).  As it stands, the format, channels, number of
152   * bits & sample rate are assumed to be common.  In the future perhaps these
153   * should be the responsibility of the LL driver - and then if a card really
154   * does not share items between record & playback they can be specified
155   * separately.
156 */
157 
158 /* Thread-safeness of shared_resources notes: 31/01/2001
159  * If the user opens O_RDWR and then splits record & play between two threads
160  * both of which inherit the fd - and then starts changing things from both
161  * - we will have difficulty telling.
162  *
163  * It's bad application coding - but ...
164  * TODO: think about how to sort this out... without bogging everything down in
165  * semaphores.
166  *
167  * Similarly, the OSS spec says "all changes to parameters must be between
168  * open() and the first read() or write(). - and a bit later on (by
169  * implication) "between SNDCTL_DSP_RESET and the first read() or write() after
170  * it".  If the app is multi-threaded and this rule is broken between threads
171  * we will have trouble spotting it - and the fault will be rather obscure :-(
172  *
173  * We will try and put out at least a kmsg if we see it happen... but I think
174  * it will be quite hard to trap it with an -EXXX return... because we can't
175  * see the fault until after the damage is done.
176 */
177 
178 #include <linux/module.h>
179 #include <linux/slab.h>
180 #include <linux/sound.h>
181 #include <linux/init.h>
182 #include <linux/soundcard.h>
183 #include <linux/poll.h>
184 #include <linux/smp_lock.h>
185 
186 #include <asm/uaccess.h>
187 
188 #include "dmasound.h"
189 
190 #define DMASOUND_CORE_REVISION 1
191 #define DMASOUND_CORE_EDITION 6
192 
193     /*
194      *  Declarations
195      */
196 
197 int dmasound_catchRadius = 0;
198 module_param(dmasound_catchRadius, int, 0);
199 
200 static unsigned int numWriteBufs = DEFAULT_N_BUFFERS;
201 module_param(numWriteBufs, int, 0);
202 static unsigned int writeBufSize = DEFAULT_BUFF_SIZE ;	/* in bytes */
203 module_param(writeBufSize, int, 0);
204 
205 MODULE_LICENSE("GPL");
206 
207 #ifdef MODULE
208 static int sq_unit = -1;
209 static int mixer_unit = -1;
210 static int state_unit = -1;
211 static int irq_installed;
212 #endif /* MODULE */
213 
214 /* control over who can modify resources shared between play/record */
215 static fmode_t shared_resource_owner;
216 static int shared_resources_initialised;
217 
218     /*
219      *  Mid level stuff
220      */
221 
222 struct sound_settings dmasound = {
223 	.lock = __SPIN_LOCK_UNLOCKED(dmasound.lock)
224 };
225 
226 static inline void sound_silence(void)
227 {
228 	dmasound.mach.silence(); /* _MUST_ stop DMA */
229 }
230 
231 static inline int sound_set_format(int format)
232 {
233 	return dmasound.mach.setFormat(format);
234 }
235 
236 
237 static int sound_set_speed(int speed)
238 {
239 	if (speed < 0)
240 		return dmasound.soft.speed;
241 
242 	/* trap out-of-range speed settings.
243 	   at present we allow (arbitrarily) low rates - using soft
244 	   up-conversion - but we can't allow > max because there is
245 	   no soft down-conversion.
246 	*/
247 	if (dmasound.mach.max_dsp_speed &&
248 	   (speed > dmasound.mach.max_dsp_speed))
249 		speed = dmasound.mach.max_dsp_speed ;
250 
251 	dmasound.soft.speed = speed;
252 
253 	if (dmasound.minDev == SND_DEV_DSP)
254 		dmasound.dsp.speed = dmasound.soft.speed;
255 
256 	return dmasound.soft.speed;
257 }
258 
259 static int sound_set_stereo(int stereo)
260 {
261 	if (stereo < 0)
262 		return dmasound.soft.stereo;
263 
264 	stereo = !!stereo;    /* should be 0 or 1 now */
265 
266 	dmasound.soft.stereo = stereo;
267 	if (dmasound.minDev == SND_DEV_DSP)
268 		dmasound.dsp.stereo = stereo;
269 
270 	return stereo;
271 }
272 
273 static ssize_t sound_copy_translate(TRANS *trans, const u_char __user *userPtr,
274 				    size_t userCount, u_char frame[],
275 				    ssize_t *frameUsed, ssize_t frameLeft)
276 {
277 	ssize_t (*ct_func)(const u_char __user *, size_t, u_char *, ssize_t *, ssize_t);
278 
279 	switch (dmasound.soft.format) {
280 	    case AFMT_MU_LAW:
281 		ct_func = trans->ct_ulaw;
282 		break;
283 	    case AFMT_A_LAW:
284 		ct_func = trans->ct_alaw;
285 		break;
286 	    case AFMT_S8:
287 		ct_func = trans->ct_s8;
288 		break;
289 	    case AFMT_U8:
290 		ct_func = trans->ct_u8;
291 		break;
292 	    case AFMT_S16_BE:
293 		ct_func = trans->ct_s16be;
294 		break;
295 	    case AFMT_U16_BE:
296 		ct_func = trans->ct_u16be;
297 		break;
298 	    case AFMT_S16_LE:
299 		ct_func = trans->ct_s16le;
300 		break;
301 	    case AFMT_U16_LE:
302 		ct_func = trans->ct_u16le;
303 		break;
304 	    default:
305 		return 0;
306 	}
307 	/* if the user has requested a non-existent translation don't try
308 	   to call it but just return 0 bytes moved
309 	*/
310 	if (ct_func)
311 		return ct_func(userPtr, userCount, frame, frameUsed, frameLeft);
312 	return 0;
313 }
314 
315     /*
316      *  /dev/mixer abstraction
317      */
318 
319 static struct {
320     int busy;
321     int modify_counter;
322 } mixer;
323 
324 static int mixer_open(struct inode *inode, struct file *file)
325 {
326 	if (!try_module_get(dmasound.mach.owner))
327 		return -ENODEV;
328 	mixer.busy = 1;
329 	return 0;
330 }
331 
332 static int mixer_release(struct inode *inode, struct file *file)
333 {
334 	lock_kernel();
335 	mixer.busy = 0;
336 	module_put(dmasound.mach.owner);
337 	unlock_kernel();
338 	return 0;
339 }
340 static int mixer_ioctl(struct inode *inode, struct file *file, u_int cmd,
341 		       u_long arg)
342 {
343 	if (_SIOC_DIR(cmd) & _SIOC_WRITE)
344 	    mixer.modify_counter++;
345 	switch (cmd) {
346 	    case OSS_GETVERSION:
347 		return IOCTL_OUT(arg, SOUND_VERSION);
348 	    case SOUND_MIXER_INFO:
349 		{
350 		    mixer_info info;
351 		    memset(&info, 0, sizeof(info));
352 		    strlcpy(info.id, dmasound.mach.name2, sizeof(info.id));
353 		    strlcpy(info.name, dmasound.mach.name2, sizeof(info.name));
354 		    info.modify_counter = mixer.modify_counter;
355 		    if (copy_to_user((void __user *)arg, &info, sizeof(info)))
356 			    return -EFAULT;
357 		    return 0;
358 		}
359 	}
360 	if (dmasound.mach.mixer_ioctl)
361 	    return dmasound.mach.mixer_ioctl(cmd, arg);
362 	return -EINVAL;
363 }
364 
365 static const struct file_operations mixer_fops =
366 {
367 	.owner		= THIS_MODULE,
368 	.llseek		= no_llseek,
369 	.ioctl		= mixer_ioctl,
370 	.open		= mixer_open,
371 	.release	= mixer_release,
372 };
373 
374 static void mixer_init(void)
375 {
376 #ifndef MODULE
377 	int mixer_unit;
378 #endif
379 	mixer_unit = register_sound_mixer(&mixer_fops, -1);
380 	if (mixer_unit < 0)
381 		return;
382 
383 	mixer.busy = 0;
384 	dmasound.treble = 0;
385 	dmasound.bass = 0;
386 	if (dmasound.mach.mixer_init)
387 	    dmasound.mach.mixer_init();
388 }
389 
390 
391     /*
392      *  Sound queue stuff, the heart of the driver
393      */
394 
395 struct sound_queue dmasound_write_sq;
396 static void sq_reset_output(void) ;
397 
398 static int sq_allocate_buffers(struct sound_queue *sq, int num, int size)
399 {
400 	int i;
401 
402 	if (sq->buffers)
403 		return 0;
404 	sq->numBufs = num;
405 	sq->bufSize = size;
406 	sq->buffers = kmalloc (num * sizeof(char *), GFP_KERNEL);
407 	if (!sq->buffers)
408 		return -ENOMEM;
409 	for (i = 0; i < num; i++) {
410 		sq->buffers[i] = dmasound.mach.dma_alloc(size, GFP_KERNEL);
411 		if (!sq->buffers[i]) {
412 			while (i--)
413 				dmasound.mach.dma_free(sq->buffers[i], size);
414 			kfree(sq->buffers);
415 			sq->buffers = NULL;
416 			return -ENOMEM;
417 		}
418 	}
419 	return 0;
420 }
421 
422 static void sq_release_buffers(struct sound_queue *sq)
423 {
424 	int i;
425 
426 	if (sq->buffers) {
427 		for (i = 0; i < sq->numBufs; i++)
428 			dmasound.mach.dma_free(sq->buffers[i], sq->bufSize);
429 		kfree(sq->buffers);
430 		sq->buffers = NULL;
431 	}
432 }
433 
434 
435 static int sq_setup(struct sound_queue *sq)
436 {
437 	int (*setup_func)(void) = NULL;
438 	int hard_frame ;
439 
440 	if (sq->locked) { /* are we already set? - and not changeable */
441 #ifdef DEBUG_DMASOUND
442 printk("dmasound_core: tried to sq_setup a locked queue\n") ;
443 #endif
444 		return -EINVAL ;
445 	}
446 	sq->locked = 1 ; /* don't think we have a race prob. here _check_ */
447 
448 	/* make sure that the parameters are set up
449 	   This should have been done already...
450 	*/
451 
452 	dmasound.mach.init();
453 
454 	/* OK.  If the user has set fragment parameters explicitly, then we
455 	   should leave them alone... as long as they are valid.
456 	   Invalid user fragment params can occur if we allow the whole buffer
457 	   to be used when the user requests the fragments sizes (with no soft
458 	   x-lation) and then the user subsequently sets a soft x-lation that
459 	   requires increased internal buffering.
460 
461 	   Othwerwise (if the user did not set them) OSS says that we should
462 	   select frag params on the basis of 0.5 s output & 0.1 s input
463 	   latency. (TODO.  For now we will copy in the defaults.)
464 	*/
465 
466 	if (sq->user_frags <= 0) {
467 		sq->max_count = sq->numBufs ;
468 		sq->max_active = sq->numBufs ;
469 		sq->block_size = sq->bufSize;
470 		/* set up the user info */
471 		sq->user_frags = sq->numBufs ;
472 		sq->user_frag_size = sq->bufSize ;
473 		sq->user_frag_size *=
474 			(dmasound.soft.size * (dmasound.soft.stereo+1) ) ;
475 		sq->user_frag_size /=
476 			(dmasound.hard.size * (dmasound.hard.stereo+1) ) ;
477 	} else {
478 		/* work out requested block size */
479 		sq->block_size = sq->user_frag_size ;
480 		sq->block_size *=
481 			(dmasound.hard.size * (dmasound.hard.stereo+1) ) ;
482 		sq->block_size /=
483 			(dmasound.soft.size * (dmasound.soft.stereo+1) ) ;
484 		/* the user wants to write frag-size chunks */
485 		sq->block_size *= dmasound.hard.speed ;
486 		sq->block_size /= dmasound.soft.speed ;
487 		/* this only works for size values which are powers of 2 */
488 		hard_frame =
489 			(dmasound.hard.size * (dmasound.hard.stereo+1))/8 ;
490 		sq->block_size +=  (hard_frame - 1) ;
491 		sq->block_size &= ~(hard_frame - 1) ; /* make sure we are aligned */
492 		/* let's just check for obvious mistakes */
493 		if ( sq->block_size <= 0 || sq->block_size > sq->bufSize) {
494 #ifdef DEBUG_DMASOUND
495 printk("dmasound_core: invalid frag size (user set %d)\n", sq->user_frag_size) ;
496 #endif
497 			sq->block_size = sq->bufSize ;
498 		}
499 		if ( sq->user_frags <= sq->numBufs ) {
500 			sq->max_count = sq->user_frags ;
501 			/* if user has set max_active - then use it */
502 			sq->max_active = (sq->max_active <= sq->max_count) ?
503 				sq->max_active : sq->max_count ;
504 		} else {
505 #ifdef DEBUG_DMASOUND
506 printk("dmasound_core: invalid frag count (user set %d)\n", sq->user_frags) ;
507 #endif
508 			sq->max_count =
509 			sq->max_active = sq->numBufs ;
510 		}
511 	}
512 	sq->front = sq->count = sq->rear_size = 0;
513 	sq->syncing = 0;
514 	sq->active = 0;
515 
516 	if (sq == &write_sq) {
517 	    sq->rear = -1;
518 	    setup_func = dmasound.mach.write_sq_setup;
519 	}
520 	if (setup_func)
521 	    return setup_func();
522 	return 0 ;
523 }
524 
525 static inline void sq_play(void)
526 {
527 	dmasound.mach.play();
528 }
529 
530 static ssize_t sq_write(struct file *file, const char __user *src, size_t uLeft,
531 			loff_t *ppos)
532 {
533 	ssize_t uWritten = 0;
534 	u_char *dest;
535 	ssize_t uUsed = 0, bUsed, bLeft;
536 	unsigned long flags ;
537 
538 	/* ++TeSche: Is something like this necessary?
539 	 * Hey, that's an honest question! Or does any other part of the
540 	 * filesystem already checks this situation? I really don't know.
541 	 */
542 	if (uLeft == 0)
543 		return 0;
544 
545 	/* implement any changes we have made to the soft/hard params.
546 	   this is not satisfactory really, all we have done up to now is to
547 	   say what we would like - there hasn't been any real checking of capability
548 	*/
549 
550 	if (shared_resources_initialised == 0) {
551 		dmasound.mach.init() ;
552 		shared_resources_initialised = 1 ;
553 	}
554 
555 	/* set up the sq if it is not already done. This may seem a dumb place
556 	   to do it - but it is what OSS requires.  It means that write() can
557 	   return memory allocation errors.  To avoid this possibility use the
558 	   GETBLKSIZE or GETOSPACE ioctls (after you've fiddled with all the
559 	   params you want to change) - these ioctls also force the setup.
560 	*/
561 
562 	if (write_sq.locked == 0) {
563 		if ((uWritten = sq_setup(&write_sq)) < 0) return uWritten ;
564 		uWritten = 0 ;
565 	}
566 
567 /* FIXME: I think that this may be the wrong behaviour when we get strapped
568 	for time and the cpu is close to being (or actually) behind in sending data.
569 	- because we've lost the time that the N samples, already in the buffer,
570 	would have given us to get here with the next lot from the user.
571 */
572 	/* The interrupt doesn't start to play the last, incomplete frame.
573 	 * Thus we can append to it without disabling the interrupts! (Note
574 	 * also that write_sq.rear isn't affected by the interrupt.)
575 	 */
576 
577 	/* as of 1.6 this behaviour changes if SNDCTL_DSP_POST has been issued:
578 	   this will mimic the behaviour of syncing and allow the sq_play() to
579 	   queue a partial fragment.  Since sq_play() may/will be called from
580 	   the IRQ handler - at least on Pmac we have to deal with it.
581 	   The strategy - possibly not optimum - is to kill _POST status if we
582 	   get here.  This seems, at least, reasonable - in the sense that POST
583 	   is supposed to indicate that we might not write before the queue
584 	   is drained - and if we get here in time then it does not apply.
585 	*/
586 
587 	spin_lock_irqsave(&dmasound.lock, flags);
588 	write_sq.syncing &= ~2 ; /* take out POST status */
589 	spin_unlock_irqrestore(&dmasound.lock, flags);
590 
591 	if (write_sq.count > 0 &&
592 	    (bLeft = write_sq.block_size-write_sq.rear_size) > 0) {
593 		dest = write_sq.buffers[write_sq.rear];
594 		bUsed = write_sq.rear_size;
595 		uUsed = sound_copy_translate(dmasound.trans_write, src, uLeft,
596 					     dest, &bUsed, bLeft);
597 		if (uUsed <= 0)
598 			return uUsed;
599 		src += uUsed;
600 		uWritten += uUsed;
601 		uLeft = (uUsed <= uLeft) ? (uLeft - uUsed) : 0 ; /* paranoia */
602 		write_sq.rear_size = bUsed;
603 	}
604 
605 	while (uLeft) {
606 		while (write_sq.count >= write_sq.max_active) {
607 			sq_play();
608 			if (write_sq.non_blocking)
609 				return uWritten > 0 ? uWritten : -EAGAIN;
610 			SLEEP(write_sq.action_queue);
611 			if (signal_pending(current))
612 				return uWritten > 0 ? uWritten : -EINTR;
613 		}
614 
615 		/* Here, we can avoid disabling the interrupt by first
616 		 * copying and translating the data, and then updating
617 		 * the write_sq variables. Until this is done, the interrupt
618 		 * won't see the new frame and we can work on it
619 		 * undisturbed.
620 		 */
621 
622 		dest = write_sq.buffers[(write_sq.rear+1) % write_sq.max_count];
623 		bUsed = 0;
624 		bLeft = write_sq.block_size;
625 		uUsed = sound_copy_translate(dmasound.trans_write, src, uLeft,
626 					     dest, &bUsed, bLeft);
627 		if (uUsed <= 0)
628 			break;
629 		src += uUsed;
630 		uWritten += uUsed;
631 		uLeft = (uUsed <= uLeft) ? (uLeft - uUsed) : 0 ; /* paranoia */
632 		if (bUsed) {
633 			write_sq.rear = (write_sq.rear+1) % write_sq.max_count;
634 			write_sq.rear_size = bUsed;
635 			write_sq.count++;
636 		}
637 	} /* uUsed may have been 0 */
638 
639 	sq_play();
640 
641 	return uUsed < 0? uUsed: uWritten;
642 }
643 
644 static unsigned int sq_poll(struct file *file, struct poll_table_struct *wait)
645 {
646 	unsigned int mask = 0;
647 	int retVal;
648 
649 	if (write_sq.locked == 0) {
650 		if ((retVal = sq_setup(&write_sq)) < 0)
651 			return retVal;
652 		return 0;
653 	}
654 	if (file->f_mode & FMODE_WRITE )
655 		poll_wait(file, &write_sq.action_queue, wait);
656 	if (file->f_mode & FMODE_WRITE)
657 		if (write_sq.count < write_sq.max_active || write_sq.block_size - write_sq.rear_size > 0)
658 			mask |= POLLOUT | POLLWRNORM;
659 	return mask;
660 
661 }
662 
663 static inline void sq_init_waitqueue(struct sound_queue *sq)
664 {
665 	init_waitqueue_head(&sq->action_queue);
666 	init_waitqueue_head(&sq->open_queue);
667 	init_waitqueue_head(&sq->sync_queue);
668 	sq->busy = 0;
669 }
670 
671 #if 0 /* blocking open() */
672 static inline void sq_wake_up(struct sound_queue *sq, struct file *file,
673 			      fmode_t mode)
674 {
675 	if (file->f_mode & mode) {
676 		sq->busy = 0; /* CHECK: IS THIS OK??? */
677 		WAKE_UP(sq->open_queue);
678 	}
679 }
680 #endif
681 
682 static int sq_open2(struct sound_queue *sq, struct file *file, fmode_t mode,
683 		    int numbufs, int bufsize)
684 {
685 	int rc = 0;
686 
687 	if (file->f_mode & mode) {
688 		if (sq->busy) {
689 #if 0 /* blocking open() */
690 			rc = -EBUSY;
691 			if (file->f_flags & O_NONBLOCK)
692 				return rc;
693 			rc = -EINTR;
694 			while (sq->busy) {
695 				SLEEP(sq->open_queue);
696 				if (signal_pending(current))
697 					return rc;
698 			}
699 			rc = 0;
700 #else
701 			/* OSS manual says we will return EBUSY regardless
702 			   of O_NOBLOCK.
703 			*/
704 			return -EBUSY ;
705 #endif
706 		}
707 		sq->busy = 1; /* Let's play spot-the-race-condition */
708 
709 		/* allocate the default number & size of buffers.
710 		   (i.e. specified in _setup() or as module params)
711 		   can't be changed at the moment - but _could_ be perhaps
712 		   in the setfragments ioctl.
713 		*/
714 		if (( rc = sq_allocate_buffers(sq, numbufs, bufsize))) {
715 #if 0 /* blocking open() */
716 			sq_wake_up(sq, file, mode);
717 #else
718 			sq->busy = 0 ;
719 #endif
720 			return rc;
721 		}
722 
723 		sq->non_blocking = file->f_flags & O_NONBLOCK;
724 	}
725 	return rc;
726 }
727 
728 #define write_sq_init_waitqueue()	sq_init_waitqueue(&write_sq)
729 #if 0 /* blocking open() */
730 #define write_sq_wake_up(file)		sq_wake_up(&write_sq, file, FMODE_WRITE)
731 #endif
732 #define write_sq_release_buffers()	sq_release_buffers(&write_sq)
733 #define write_sq_open(file)	\
734 	sq_open2(&write_sq, file, FMODE_WRITE, numWriteBufs, writeBufSize )
735 
736 static int sq_open(struct inode *inode, struct file *file)
737 {
738 	int rc;
739 
740 	if (!try_module_get(dmasound.mach.owner))
741 		return -ENODEV;
742 
743 	rc = write_sq_open(file); /* checks the f_mode */
744 	if (rc)
745 		goto out;
746 	if (file->f_mode & FMODE_READ) {
747 		/* TODO: if O_RDWR, release any resources grabbed by write part */
748 		rc = -ENXIO ; /* I think this is what is required by open(2) */
749 		goto out;
750 	}
751 
752 	if (dmasound.mach.sq_open)
753 	    dmasound.mach.sq_open(file->f_mode);
754 
755 	/* CHECK whether this is sensible - in the case that dsp0 could be opened
756 	  O_RDONLY and dsp1 could be opened O_WRONLY
757 	*/
758 
759 	dmasound.minDev = iminor(inode) & 0x0f;
760 
761 	/* OK. - we should make some attempt at consistency. At least the H'ware
762 	   options should be set with a valid mode.  We will make it that the LL
763 	   driver must supply defaults for hard & soft params.
764 	*/
765 
766 	if (shared_resource_owner == 0) {
767 		/* you can make this AFMT_U8/mono/8K if you want to mimic old
768 		   OSS behaviour - while we still have soft translations ;-) */
769 		dmasound.soft = dmasound.mach.default_soft ;
770 		dmasound.dsp = dmasound.mach.default_soft ;
771 		dmasound.hard = dmasound.mach.default_hard ;
772 	}
773 
774 #ifndef DMASOUND_STRICT_OSS_COMPLIANCE
775 	/* none of the current LL drivers can actually do this "native" at the moment
776 	   OSS does not really require us to supply /dev/audio if we can't do it.
777 	*/
778 	if (dmasound.minDev == SND_DEV_AUDIO) {
779 		sound_set_speed(8000);
780 		sound_set_stereo(0);
781 		sound_set_format(AFMT_MU_LAW);
782 	}
783 #endif
784 
785 	return 0;
786  out:
787 	module_put(dmasound.mach.owner);
788 	return rc;
789 }
790 
791 static void sq_reset_output(void)
792 {
793 	sound_silence(); /* this _must_ stop DMA, we might be about to lose the buffers */
794 	write_sq.active = 0;
795 	write_sq.count = 0;
796 	write_sq.rear_size = 0;
797 	/* write_sq.front = (write_sq.rear+1) % write_sq.max_count;*/
798 	write_sq.front = 0 ;
799 	write_sq.rear = -1 ; /* same as for set-up */
800 
801 	/* OK - we can unlock the parameters and fragment settings */
802 	write_sq.locked = 0 ;
803 	write_sq.user_frags = 0 ;
804 	write_sq.user_frag_size = 0 ;
805 }
806 
807 static void sq_reset(void)
808 {
809 	sq_reset_output() ;
810 	/* we could consider resetting the shared_resources_owner here... but I
811 	   think it is probably still rather non-obvious to application writer
812 	*/
813 
814 	/* we release everything else though */
815 	shared_resources_initialised = 0 ;
816 }
817 
818 static int sq_fsync(struct file *filp, struct dentry *dentry)
819 {
820 	int rc = 0;
821 	int timeout = 5;
822 
823 	write_sq.syncing |= 1;
824 	sq_play();	/* there may be an incomplete frame waiting */
825 
826 	while (write_sq.active) {
827 		SLEEP(write_sq.sync_queue);
828 		if (signal_pending(current)) {
829 			/* While waiting for audio output to drain, an
830 			 * interrupt occurred.  Stop audio output immediately
831 			 * and clear the queue. */
832 			sq_reset_output();
833 			rc = -EINTR;
834 			break;
835 		}
836 		if (!--timeout) {
837 			printk(KERN_WARNING "dmasound: Timeout draining output\n");
838 			sq_reset_output();
839 			rc = -EIO;
840 			break;
841 		}
842 	}
843 
844 	/* flag no sync regardless of whether we had a DSP_POST or not */
845 	write_sq.syncing = 0 ;
846 	return rc;
847 }
848 
849 static int sq_release(struct inode *inode, struct file *file)
850 {
851 	int rc = 0;
852 
853 	lock_kernel();
854 
855 	if (file->f_mode & FMODE_WRITE) {
856 		if (write_sq.busy)
857 			rc = sq_fsync(file, file->f_path.dentry);
858 
859 		sq_reset_output() ; /* make sure dma is stopped and all is quiet */
860 		write_sq_release_buffers();
861 		write_sq.busy = 0;
862 	}
863 
864 	if (file->f_mode & shared_resource_owner) { /* it's us that has them */
865 		shared_resource_owner = 0 ;
866 		shared_resources_initialised = 0 ;
867 		dmasound.hard = dmasound.mach.default_hard ;
868 	}
869 
870 	module_put(dmasound.mach.owner);
871 
872 #if 0 /* blocking open() */
873 	/* Wake up a process waiting for the queue being released.
874 	 * Note: There may be several processes waiting for a call
875 	 * to open() returning. */
876 
877 	/* Iain: hmm I don't understand this next comment ... */
878 	/* There is probably a DOS atack here. They change the mode flag. */
879 	/* XXX add check here,*/
880 	read_sq_wake_up(file); /* checks f_mode */
881 	write_sq_wake_up(file); /* checks f_mode */
882 #endif /* blocking open() */
883 
884 	unlock_kernel();
885 
886 	return rc;
887 }
888 
889 /* here we see if we have a right to modify format, channels, size and so on
890    if no-one else has claimed it already then we do...
891 
892    TODO: We might change this to mask O_RDWR such that only one or the other channel
893    is the owner - if we have problems.
894 */
895 
896 static int shared_resources_are_mine(fmode_t md)
897 {
898 	if (shared_resource_owner)
899 		return (shared_resource_owner & md) != 0;
900 	else {
901 		shared_resource_owner = md ;
902 		return 1 ;
903 	}
904 }
905 
906 /* if either queue is locked we must deny the right to change shared params
907 */
908 
909 static int queues_are_quiescent(void)
910 {
911 	if (write_sq.locked)
912 		return 0 ;
913 	return 1 ;
914 }
915 
916 /* check and set a queue's fragments per user's wishes...
917    we will check against the pre-defined literals and the actual sizes.
918    This is a bit fraught - because soft translations can mess with our
919    buffer requirements *after* this call - OSS says "call setfrags first"
920 */
921 
922 /* It is possible to replace all the -EINVAL returns with an override that
923    just puts the allowable value in.  This may be what many OSS apps require
924 */
925 
926 static int set_queue_frags(struct sound_queue *sq, int bufs, int size)
927 {
928 	if (sq->locked) {
929 #ifdef DEBUG_DMASOUND
930 printk("dmasound_core: tried to set_queue_frags on a locked queue\n") ;
931 #endif
932 		return -EINVAL ;
933 	}
934 
935 	if ((size < MIN_FRAG_SIZE) || (size > MAX_FRAG_SIZE))
936 		return -EINVAL ;
937 	size = (1<<size) ; /* now in bytes */
938 	if (size > sq->bufSize)
939 		return -EINVAL ; /* this might still not work */
940 
941 	if (bufs <= 0)
942 		return -EINVAL ;
943 	if (bufs > sq->numBufs) /* the user is allowed say "don't care" with 0x7fff */
944 		bufs = sq->numBufs ;
945 
946 	/* there is, currently, no way to specify max_active separately
947 	   from max_count.  This could be a LL driver issue - I guess
948 	   if there is a requirement for these values to be different then
949 	  we will have to pass that info. up to this level.
950 	*/
951 	sq->user_frags =
952 	sq->max_active = bufs ;
953 	sq->user_frag_size = size ;
954 
955 	return 0 ;
956 }
957 
958 static int sq_ioctl(struct inode *inode, struct file *file, u_int cmd,
959 		    u_long arg)
960 {
961 	int val, result;
962 	u_long fmt;
963 	int data;
964 	int size, nbufs;
965 	audio_buf_info info;
966 
967 	switch (cmd) {
968 	case SNDCTL_DSP_RESET:
969 		sq_reset();
970 		return 0;
971 		break ;
972 	case SNDCTL_DSP_GETFMTS:
973 		fmt = dmasound.mach.hardware_afmts ; /* this is what OSS says.. */
974 		return IOCTL_OUT(arg, fmt);
975 		break ;
976 	case SNDCTL_DSP_GETBLKSIZE:
977 		/* this should tell the caller about bytes that the app can
978 		   read/write - the app doesn't care about our internal buffers.
979 		   We force sq_setup() here as per OSS 1.1 (which should
980 		   compute the values necessary).
981 		   Since there is no mechanism to specify read/write separately, for
982 		   fds opened O_RDWR, the write_sq values will, arbitrarily, overwrite
983 		   the read_sq ones.
984 		*/
985 		size = 0 ;
986 		if (file->f_mode & FMODE_WRITE) {
987 			if ( !write_sq.locked )
988 				sq_setup(&write_sq) ;
989 			size = write_sq.user_frag_size ;
990 		}
991 		return IOCTL_OUT(arg, size);
992 		break ;
993 	case SNDCTL_DSP_POST:
994 		/* all we are going to do is to tell the LL that any
995 		   partial frags can be queued for output.
996 		   The LL will have to clear this flag when last output
997 		   is queued.
998 		*/
999 		write_sq.syncing |= 0x2 ;
1000 		sq_play() ;
1001 		return 0 ;
1002 	case SNDCTL_DSP_SYNC:
1003 		/* This call, effectively, has the same behaviour as SNDCTL_DSP_RESET
1004 		   except that it waits for output to finish before resetting
1005 		   everything - read, however, is killed imediately.
1006 		*/
1007 		result = 0 ;
1008 		if (file->f_mode & FMODE_WRITE) {
1009 			result = sq_fsync(file, file->f_path.dentry);
1010 			sq_reset_output() ;
1011 		}
1012 		/* if we are the shared resource owner then release them */
1013 		if (file->f_mode & shared_resource_owner)
1014 			shared_resources_initialised = 0 ;
1015 		return result ;
1016 		break ;
1017 	case SOUND_PCM_READ_RATE:
1018 		return IOCTL_OUT(arg, dmasound.soft.speed);
1019 	case SNDCTL_DSP_SPEED:
1020 		/* changing this on the fly will have weird effects on the sound.
1021 		   Where there are rate conversions implemented in soft form - it
1022 		   will cause the _ctx_xxx() functions to be substituted.
1023 		   However, there doesn't appear to be any reason to dis-allow it from
1024 		   a driver pov.
1025 		*/
1026 		if (shared_resources_are_mine(file->f_mode)) {
1027 			IOCTL_IN(arg, data);
1028 			data = sound_set_speed(data) ;
1029 			shared_resources_initialised = 0 ;
1030 			return IOCTL_OUT(arg, data);
1031 		} else
1032 			return -EINVAL ;
1033 		break ;
1034 	/* OSS says these next 4 actions are undefined when the device is
1035 	   busy/active - we will just return -EINVAL.
1036 	   To be allowed to change one - (a) you have to own the right
1037 	    (b) the queue(s) must be quiescent
1038 	*/
1039 	case SNDCTL_DSP_STEREO:
1040 		if (shared_resources_are_mine(file->f_mode) &&
1041 		    queues_are_quiescent()) {
1042 			IOCTL_IN(arg, data);
1043 			shared_resources_initialised = 0 ;
1044 			return IOCTL_OUT(arg, sound_set_stereo(data));
1045 		} else
1046 			return -EINVAL ;
1047 		break ;
1048 	case SOUND_PCM_WRITE_CHANNELS:
1049 		if (shared_resources_are_mine(file->f_mode) &&
1050 		    queues_are_quiescent()) {
1051 			IOCTL_IN(arg, data);
1052 			/* the user might ask for 20 channels, we will return 1 or 2 */
1053 			shared_resources_initialised = 0 ;
1054 			return IOCTL_OUT(arg, sound_set_stereo(data-1)+1);
1055 		} else
1056 			return -EINVAL ;
1057 		break ;
1058 	case SNDCTL_DSP_SETFMT:
1059 		if (shared_resources_are_mine(file->f_mode) &&
1060 		    queues_are_quiescent()) {
1061 		    	int format;
1062 			IOCTL_IN(arg, data);
1063 			shared_resources_initialised = 0 ;
1064 			format = sound_set_format(data);
1065 			result = IOCTL_OUT(arg, format);
1066 			if (result < 0)
1067 				return result;
1068 			if (format != data && data != AFMT_QUERY)
1069 				return -EINVAL;
1070 			return 0;
1071 		} else
1072 			return -EINVAL ;
1073 	case SNDCTL_DSP_SUBDIVIDE:
1074 		return -EINVAL ;
1075 	case SNDCTL_DSP_SETFRAGMENT:
1076 		/* we can do this independently for the two queues - with the
1077 		   proviso that for fds opened O_RDWR we cannot separate the
1078 		   actions and both queues will be set per the last call.
1079 		   NOTE: this does *NOT* actually set the queue up - merely
1080 		   registers our intentions.
1081 		*/
1082 		IOCTL_IN(arg, data);
1083 		result = 0 ;
1084 		nbufs = (data >> 16) & 0x7fff ; /* 0x7fff is 'use maximum' */
1085 		size = data & 0xffff;
1086 		if (file->f_mode & FMODE_WRITE) {
1087 			result = set_queue_frags(&write_sq, nbufs, size) ;
1088 			if (result)
1089 				return result ;
1090 		}
1091 		/* NOTE: this return value is irrelevant - OSS specifically says that
1092 		   the value is 'random' and that the user _must_ check the actual
1093 		   frags values using SNDCTL_DSP_GETBLKSIZE or similar */
1094 		return IOCTL_OUT(arg, data);
1095 		break ;
1096 	case SNDCTL_DSP_GETOSPACE:
1097 		/*
1098 		*/
1099 		if (file->f_mode & FMODE_WRITE) {
1100 			if ( !write_sq.locked )
1101 				sq_setup(&write_sq) ;
1102 			info.fragments = write_sq.max_active - write_sq.count;
1103 			info.fragstotal = write_sq.max_active;
1104 			info.fragsize = write_sq.user_frag_size;
1105 			info.bytes = info.fragments * info.fragsize;
1106 			if (copy_to_user((void __user *)arg, &info, sizeof(info)))
1107 				return -EFAULT;
1108 			return 0;
1109 		} else
1110 			return -EINVAL ;
1111 		break ;
1112 	case SNDCTL_DSP_GETCAPS:
1113 		val = dmasound.mach.capabilities & 0xffffff00;
1114 		return IOCTL_OUT(arg,val);
1115 
1116 	default:
1117 		return mixer_ioctl(inode, file, cmd, arg);
1118 	}
1119 	return -EINVAL;
1120 }
1121 
1122 static const struct file_operations sq_fops =
1123 {
1124 	.owner		= THIS_MODULE,
1125 	.llseek		= no_llseek,
1126 	.write		= sq_write,
1127 	.poll		= sq_poll,
1128 	.ioctl		= sq_ioctl,
1129 	.open		= sq_open,
1130 	.release	= sq_release,
1131 };
1132 
1133 static int sq_init(void)
1134 {
1135 	const struct file_operations *fops = &sq_fops;
1136 #ifndef MODULE
1137 	int sq_unit;
1138 #endif
1139 
1140 	sq_unit = register_sound_dsp(fops, -1);
1141 	if (sq_unit < 0) {
1142 		printk(KERN_ERR "dmasound_core: couldn't register fops\n") ;
1143 		return sq_unit ;
1144 	}
1145 
1146 	write_sq_init_waitqueue();
1147 
1148 	/* These parameters will be restored for every clean open()
1149 	 * in the case of multiple open()s (e.g. dsp0 & dsp1) they
1150 	 * will be set so long as the shared resources have no owner.
1151 	 */
1152 
1153 	if (shared_resource_owner == 0) {
1154 		dmasound.soft = dmasound.mach.default_soft ;
1155 		dmasound.hard = dmasound.mach.default_hard ;
1156 		dmasound.dsp = dmasound.mach.default_soft ;
1157 		shared_resources_initialised = 0 ;
1158 	}
1159 	return 0 ;
1160 }
1161 
1162 
1163     /*
1164      *  /dev/sndstat
1165      */
1166 
1167 /* we allow more space for record-enabled because there are extra output lines.
1168    the number here must include the amount we are prepared to give to the low-level
1169    driver.
1170 */
1171 
1172 #define STAT_BUFF_LEN 768
1173 
1174 /* this is how much space we will allow the low-level driver to use
1175    in the stat buffer.  Currently, 2 * (80 character line + <NL>).
1176    We do not police this (it is up to the ll driver to be honest).
1177 */
1178 
1179 #define LOW_LEVEL_STAT_ALLOC 162
1180 
1181 static struct {
1182     int busy;
1183     char buf[STAT_BUFF_LEN];	/* state.buf should not overflow! */
1184     int len, ptr;
1185 } state;
1186 
1187 /* publish this function for use by low-level code, if required */
1188 
1189 static char *get_afmt_string(int afmt)
1190 {
1191         switch(afmt) {
1192             case AFMT_MU_LAW:
1193                 return "mu-law";
1194                 break;
1195             case AFMT_A_LAW:
1196                 return "A-law";
1197                 break;
1198             case AFMT_U8:
1199                 return "unsigned 8 bit";
1200                 break;
1201             case AFMT_S8:
1202                 return "signed 8 bit";
1203                 break;
1204             case AFMT_S16_BE:
1205                 return "signed 16 bit BE";
1206                 break;
1207             case AFMT_U16_BE:
1208                 return "unsigned 16 bit BE";
1209                 break;
1210             case AFMT_S16_LE:
1211                 return "signed 16 bit LE";
1212                 break;
1213             case AFMT_U16_LE:
1214                 return "unsigned 16 bit LE";
1215                 break;
1216 	    case 0:
1217 		return "format not set" ;
1218 		break ;
1219             default:
1220                 break ;
1221         }
1222         return "ERROR: Unsupported AFMT_XXXX code" ;
1223 }
1224 
1225 static int state_open(struct inode *inode, struct file *file)
1226 {
1227 	char *buffer = state.buf;
1228 	int len = 0;
1229 
1230 	if (state.busy)
1231 		return -EBUSY;
1232 
1233 	if (!try_module_get(dmasound.mach.owner))
1234 		return -ENODEV;
1235 	state.ptr = 0;
1236 	state.busy = 1;
1237 
1238 	len += sprintf(buffer+len, "%sDMA sound driver rev %03d :\n",
1239 		dmasound.mach.name, (DMASOUND_CORE_REVISION<<4) +
1240 		((dmasound.mach.version>>8) & 0x0f));
1241 	len += sprintf(buffer+len,
1242 		"Core driver edition %02d.%02d : %s driver edition %02d.%02d\n",
1243 		DMASOUND_CORE_REVISION, DMASOUND_CORE_EDITION, dmasound.mach.name2,
1244 		(dmasound.mach.version >> 8), (dmasound.mach.version & 0xff)) ;
1245 
1246 	/* call the low-level module to fill in any stat info. that it has
1247 	   if present.  Maximum buffer usage is specified.
1248 	*/
1249 
1250 	if (dmasound.mach.state_info)
1251 		len += dmasound.mach.state_info(buffer+len,
1252 			(size_t) LOW_LEVEL_STAT_ALLOC) ;
1253 
1254 	/* make usage of the state buffer as deterministic as poss.
1255 	   exceptional conditions could cause overrun - and this is flagged as
1256 	   a kernel error.
1257 	*/
1258 
1259 	/* formats and settings */
1260 
1261 	len += sprintf(buffer+len,"\t\t === Formats & settings ===\n") ;
1262 	len += sprintf(buffer+len,"Parameter %20s%20s\n","soft","hard") ;
1263 	len += sprintf(buffer+len,"Format   :%20s%20s\n",
1264 		get_afmt_string(dmasound.soft.format),
1265 		get_afmt_string(dmasound.hard.format));
1266 
1267 	len += sprintf(buffer+len,"Samp Rate:%14d s/sec%14d s/sec\n",
1268 		       dmasound.soft.speed, dmasound.hard.speed);
1269 
1270 	len += sprintf(buffer+len,"Channels :%20s%20s\n",
1271 		       dmasound.soft.stereo ? "stereo" : "mono",
1272 		       dmasound.hard.stereo ? "stereo" : "mono" );
1273 
1274 	/* sound queue status */
1275 
1276 	len += sprintf(buffer+len,"\t\t === Sound Queue status ===\n");
1277 	len += sprintf(buffer+len,"Allocated:%8s%6s\n","Buffers","Size") ;
1278 	len += sprintf(buffer+len,"%9s:%8d%6d\n",
1279 		"write", write_sq.numBufs, write_sq.bufSize) ;
1280 	len += sprintf(buffer+len,
1281 		"Current  : MaxFrg FragSiz MaxAct Frnt Rear "
1282 		"Cnt RrSize A B S L  xruns\n") ;
1283 	len += sprintf(buffer+len,"%9s:%7d%8d%7d%5d%5d%4d%7d%2d%2d%2d%2d%7d\n",
1284 		"write", write_sq.max_count, write_sq.block_size,
1285 		write_sq.max_active, write_sq.front, write_sq.rear,
1286 		write_sq.count, write_sq.rear_size, write_sq.active,
1287 		write_sq.busy, write_sq.syncing, write_sq.locked, write_sq.xruns) ;
1288 #ifdef DEBUG_DMASOUND
1289 printk("dmasound: stat buffer used %d bytes\n", len) ;
1290 #endif
1291 
1292 	if (len >= STAT_BUFF_LEN)
1293 		printk(KERN_ERR "dmasound_core: stat buffer overflowed!\n");
1294 
1295 	state.len = len;
1296 	return 0;
1297 }
1298 
1299 static int state_release(struct inode *inode, struct file *file)
1300 {
1301 	lock_kernel();
1302 	state.busy = 0;
1303 	module_put(dmasound.mach.owner);
1304 	unlock_kernel();
1305 	return 0;
1306 }
1307 
1308 static ssize_t state_read(struct file *file, char __user *buf, size_t count,
1309 			  loff_t *ppos)
1310 {
1311 	int n = state.len - state.ptr;
1312 	if (n > count)
1313 		n = count;
1314 	if (n <= 0)
1315 		return 0;
1316 	if (copy_to_user(buf, &state.buf[state.ptr], n))
1317 		return -EFAULT;
1318 	state.ptr += n;
1319 	return n;
1320 }
1321 
1322 static const struct file_operations state_fops = {
1323 	.owner		= THIS_MODULE,
1324 	.llseek		= no_llseek,
1325 	.read		= state_read,
1326 	.open		= state_open,
1327 	.release	= state_release,
1328 };
1329 
1330 static int state_init(void)
1331 {
1332 #ifndef MODULE
1333 	int state_unit;
1334 #endif
1335 	state_unit = register_sound_special(&state_fops, SND_DEV_STATUS);
1336 	if (state_unit < 0)
1337 		return state_unit ;
1338 	state.busy = 0;
1339 	return 0 ;
1340 }
1341 
1342 
1343     /*
1344      *  Config & Setup
1345      *
1346      *  This function is called by _one_ chipset-specific driver
1347      */
1348 
1349 int dmasound_init(void)
1350 {
1351 	int res ;
1352 #ifdef MODULE
1353 	if (irq_installed)
1354 		return -EBUSY;
1355 #endif
1356 
1357 	/* Set up sound queue, /dev/audio and /dev/dsp. */
1358 
1359 	/* Set default settings. */
1360 	if ((res = sq_init()) < 0)
1361 		return res ;
1362 
1363 	/* Set up /dev/sndstat. */
1364 	if ((res = state_init()) < 0)
1365 		return res ;
1366 
1367 	/* Set up /dev/mixer. */
1368 	mixer_init();
1369 
1370 	if (!dmasound.mach.irqinit()) {
1371 		printk(KERN_ERR "DMA sound driver: Interrupt initialization failed\n");
1372 		return -ENODEV;
1373 	}
1374 #ifdef MODULE
1375 	irq_installed = 1;
1376 #endif
1377 
1378 	printk(KERN_INFO "%s DMA sound driver rev %03d installed\n",
1379 		dmasound.mach.name, (DMASOUND_CORE_REVISION<<4) +
1380 		((dmasound.mach.version>>8) & 0x0f));
1381 	printk(KERN_INFO
1382 		"Core driver edition %02d.%02d : %s driver edition %02d.%02d\n",
1383 		DMASOUND_CORE_REVISION, DMASOUND_CORE_EDITION, dmasound.mach.name2,
1384 		(dmasound.mach.version >> 8), (dmasound.mach.version & 0xff)) ;
1385 	printk(KERN_INFO "Write will use %4d fragments of %7d bytes as default\n",
1386 		numWriteBufs, writeBufSize) ;
1387 	return 0;
1388 }
1389 
1390 #ifdef MODULE
1391 
1392 void dmasound_deinit(void)
1393 {
1394 	if (irq_installed) {
1395 		sound_silence();
1396 		dmasound.mach.irqcleanup();
1397 		irq_installed = 0;
1398 	}
1399 
1400 	write_sq_release_buffers();
1401 
1402 	if (mixer_unit >= 0)
1403 		unregister_sound_mixer(mixer_unit);
1404 	if (state_unit >= 0)
1405 		unregister_sound_special(state_unit);
1406 	if (sq_unit >= 0)
1407 		unregister_sound_dsp(sq_unit);
1408 }
1409 
1410 #else /* !MODULE */
1411 
1412 static int dmasound_setup(char *str)
1413 {
1414 	int ints[6], size;
1415 
1416 	str = get_options(str, ARRAY_SIZE(ints), ints);
1417 
1418 	/* check the bootstrap parameter for "dmasound=" */
1419 
1420 	/* FIXME: other than in the most naive of cases there is no sense in these
1421 	 *	  buffers being other than powers of two.  This is not checked yet.
1422 	 */
1423 
1424 	switch (ints[0]) {
1425 	case 3:
1426 		if ((ints[3] < 0) || (ints[3] > MAX_CATCH_RADIUS))
1427 			printk("dmasound_setup: invalid catch radius, using default = %d\n", catchRadius);
1428 		else
1429 			catchRadius = ints[3];
1430 		/* fall through */
1431 	case 2:
1432 		if (ints[1] < MIN_BUFFERS)
1433 			printk("dmasound_setup: invalid number of buffers, using default = %d\n", numWriteBufs);
1434 		else
1435 			numWriteBufs = ints[1];
1436 		/* fall through */
1437 	case 1:
1438 		if ((size = ints[2]) < 256) /* check for small buffer specs */
1439 			size <<= 10 ;
1440                 if (size < MIN_BUFSIZE || size > MAX_BUFSIZE)
1441                         printk("dmasound_setup: invalid write buffer size, using default = %d\n", writeBufSize);
1442                 else
1443                         writeBufSize = size;
1444 	case 0:
1445 		break;
1446 	default:
1447 		printk("dmasound_setup: invalid number of arguments\n");
1448 		return 0;
1449 	}
1450 	return 1;
1451 }
1452 
1453 __setup("dmasound=", dmasound_setup);
1454 
1455 #endif /* !MODULE */
1456 
1457     /*
1458      *  Conversion tables
1459      */
1460 
1461 #ifdef HAS_8BIT_TABLES
1462 /* 8 bit mu-law */
1463 
1464 char dmasound_ulaw2dma8[] = {
1465 	-126,	-122,	-118,	-114,	-110,	-106,	-102,	-98,
1466 	-94,	-90,	-86,	-82,	-78,	-74,	-70,	-66,
1467 	-63,	-61,	-59,	-57,	-55,	-53,	-51,	-49,
1468 	-47,	-45,	-43,	-41,	-39,	-37,	-35,	-33,
1469 	-31,	-30,	-29,	-28,	-27,	-26,	-25,	-24,
1470 	-23,	-22,	-21,	-20,	-19,	-18,	-17,	-16,
1471 	-16,	-15,	-15,	-14,	-14,	-13,	-13,	-12,
1472 	-12,	-11,	-11,	-10,	-10,	-9,	-9,	-8,
1473 	-8,	-8,	-7,	-7,	-7,	-7,	-6,	-6,
1474 	-6,	-6,	-5,	-5,	-5,	-5,	-4,	-4,
1475 	-4,	-4,	-4,	-4,	-3,	-3,	-3,	-3,
1476 	-3,	-3,	-3,	-3,	-2,	-2,	-2,	-2,
1477 	-2,	-2,	-2,	-2,	-2,	-2,	-2,	-2,
1478 	-1,	-1,	-1,	-1,	-1,	-1,	-1,	-1,
1479 	-1,	-1,	-1,	-1,	-1,	-1,	-1,	-1,
1480 	-1,	-1,	-1,	-1,	-1,	-1,	-1,	0,
1481 	125,	121,	117,	113,	109,	105,	101,	97,
1482 	93,	89,	85,	81,	77,	73,	69,	65,
1483 	62,	60,	58,	56,	54,	52,	50,	48,
1484 	46,	44,	42,	40,	38,	36,	34,	32,
1485 	30,	29,	28,	27,	26,	25,	24,	23,
1486 	22,	21,	20,	19,	18,	17,	16,	15,
1487 	15,	14,	14,	13,	13,	12,	12,	11,
1488 	11,	10,	10,	9,	9,	8,	8,	7,
1489 	7,	7,	6,	6,	6,	6,	5,	5,
1490 	5,	5,	4,	4,	4,	4,	3,	3,
1491 	3,	3,	3,	3,	2,	2,	2,	2,
1492 	2,	2,	2,	2,	1,	1,	1,	1,
1493 	1,	1,	1,	1,	1,	1,	1,	1,
1494 	0,	0,	0,	0,	0,	0,	0,	0,
1495 	0,	0,	0,	0,	0,	0,	0,	0,
1496 	0,	0,	0,	0,	0,	0,	0,	0
1497 };
1498 
1499 /* 8 bit A-law */
1500 
1501 char dmasound_alaw2dma8[] = {
1502 	-22,	-21,	-24,	-23,	-18,	-17,	-20,	-19,
1503 	-30,	-29,	-32,	-31,	-26,	-25,	-28,	-27,
1504 	-11,	-11,	-12,	-12,	-9,	-9,	-10,	-10,
1505 	-15,	-15,	-16,	-16,	-13,	-13,	-14,	-14,
1506 	-86,	-82,	-94,	-90,	-70,	-66,	-78,	-74,
1507 	-118,	-114,	-126,	-122,	-102,	-98,	-110,	-106,
1508 	-43,	-41,	-47,	-45,	-35,	-33,	-39,	-37,
1509 	-59,	-57,	-63,	-61,	-51,	-49,	-55,	-53,
1510 	-2,	-2,	-2,	-2,	-2,	-2,	-2,	-2,
1511 	-2,	-2,	-2,	-2,	-2,	-2,	-2,	-2,
1512 	-1,	-1,	-1,	-1,	-1,	-1,	-1,	-1,
1513 	-1,	-1,	-1,	-1,	-1,	-1,	-1,	-1,
1514 	-6,	-6,	-6,	-6,	-5,	-5,	-5,	-5,
1515 	-8,	-8,	-8,	-8,	-7,	-7,	-7,	-7,
1516 	-3,	-3,	-3,	-3,	-3,	-3,	-3,	-3,
1517 	-4,	-4,	-4,	-4,	-4,	-4,	-4,	-4,
1518 	21,	20,	23,	22,	17,	16,	19,	18,
1519 	29,	28,	31,	30,	25,	24,	27,	26,
1520 	10,	10,	11,	11,	8,	8,	9,	9,
1521 	14,	14,	15,	15,	12,	12,	13,	13,
1522 	86,	82,	94,	90,	70,	66,	78,	74,
1523 	118,	114,	126,	122,	102,	98,	110,	106,
1524 	43,	41,	47,	45,	35,	33,	39,	37,
1525 	59,	57,	63,	61,	51,	49,	55,	53,
1526 	1,	1,	1,	1,	1,	1,	1,	1,
1527 	1,	1,	1,	1,	1,	1,	1,	1,
1528 	0,	0,	0,	0,	0,	0,	0,	0,
1529 	0,	0,	0,	0,	0,	0,	0,	0,
1530 	5,	5,	5,	5,	4,	4,	4,	4,
1531 	7,	7,	7,	7,	6,	6,	6,	6,
1532 	2,	2,	2,	2,	2,	2,	2,	2,
1533 	3,	3,	3,	3,	3,	3,	3,	3
1534 };
1535 #endif /* HAS_8BIT_TABLES */
1536 
1537     /*
1538      *  Visible symbols for modules
1539      */
1540 
1541 EXPORT_SYMBOL(dmasound);
1542 EXPORT_SYMBOL(dmasound_init);
1543 #ifdef MODULE
1544 EXPORT_SYMBOL(dmasound_deinit);
1545 #endif
1546 EXPORT_SYMBOL(dmasound_write_sq);
1547 EXPORT_SYMBOL(dmasound_catchRadius);
1548 #ifdef HAS_8BIT_TABLES
1549 EXPORT_SYMBOL(dmasound_ulaw2dma8);
1550 EXPORT_SYMBOL(dmasound_alaw2dma8);
1551 #endif
1552