xref: /linux/sound/oss/dmasound/dmasound_core.c (revision 02680c23d7b3febe45ea3d4f9818c2b2dc89020a)
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/mutex.h>
185 #include <linux/sched/signal.h>
186 
187 #include <linux/uaccess.h>
188 
189 #include "dmasound.h"
190 
191 #define DMASOUND_CORE_REVISION 1
192 #define DMASOUND_CORE_EDITION 6
193 
194     /*
195      *  Declarations
196      */
197 
198 static DEFINE_MUTEX(dmasound_core_mutex);
199 int dmasound_catchRadius = 0;
200 module_param(dmasound_catchRadius, int, 0);
201 
202 static unsigned int numWriteBufs = DEFAULT_N_BUFFERS;
203 module_param(numWriteBufs, int, 0);
204 static unsigned int writeBufSize = DEFAULT_BUFF_SIZE ;	/* in bytes */
205 module_param(writeBufSize, int, 0);
206 
207 MODULE_LICENSE("GPL");
208 
209 #ifdef MODULE
210 static int sq_unit = -1;
211 static int mixer_unit = -1;
212 static int state_unit = -1;
213 static int irq_installed;
214 #endif /* MODULE */
215 
216 /* control over who can modify resources shared between play/record */
217 static fmode_t shared_resource_owner;
218 static int shared_resources_initialised;
219 
220     /*
221      *  Mid level stuff
222      */
223 
224 struct sound_settings dmasound = {
225 	.lock = __SPIN_LOCK_UNLOCKED(dmasound.lock)
226 };
227 
228 static inline void sound_silence(void)
229 {
230 	dmasound.mach.silence(); /* _MUST_ stop DMA */
231 }
232 
233 static inline int sound_set_format(int format)
234 {
235 	return dmasound.mach.setFormat(format);
236 }
237 
238 
239 static int sound_set_speed(int speed)
240 {
241 	if (speed < 0)
242 		return dmasound.soft.speed;
243 
244 	/* trap out-of-range speed settings.
245 	   at present we allow (arbitrarily) low rates - using soft
246 	   up-conversion - but we can't allow > max because there is
247 	   no soft down-conversion.
248 	*/
249 	if (dmasound.mach.max_dsp_speed &&
250 	   (speed > dmasound.mach.max_dsp_speed))
251 		speed = dmasound.mach.max_dsp_speed ;
252 
253 	dmasound.soft.speed = speed;
254 
255 	if (dmasound.minDev == SND_DEV_DSP)
256 		dmasound.dsp.speed = dmasound.soft.speed;
257 
258 	return dmasound.soft.speed;
259 }
260 
261 static int sound_set_stereo(int stereo)
262 {
263 	if (stereo < 0)
264 		return dmasound.soft.stereo;
265 
266 	stereo = !!stereo;    /* should be 0 or 1 now */
267 
268 	dmasound.soft.stereo = stereo;
269 	if (dmasound.minDev == SND_DEV_DSP)
270 		dmasound.dsp.stereo = stereo;
271 
272 	return stereo;
273 }
274 
275 static ssize_t sound_copy_translate(TRANS *trans, const u_char __user *userPtr,
276 				    size_t userCount, u_char frame[],
277 				    ssize_t *frameUsed, ssize_t frameLeft)
278 {
279 	ssize_t (*ct_func)(const u_char __user *, size_t, u_char *, ssize_t *, ssize_t);
280 
281 	switch (dmasound.soft.format) {
282 	    case AFMT_MU_LAW:
283 		ct_func = trans->ct_ulaw;
284 		break;
285 	    case AFMT_A_LAW:
286 		ct_func = trans->ct_alaw;
287 		break;
288 	    case AFMT_S8:
289 		ct_func = trans->ct_s8;
290 		break;
291 	    case AFMT_U8:
292 		ct_func = trans->ct_u8;
293 		break;
294 	    case AFMT_S16_BE:
295 		ct_func = trans->ct_s16be;
296 		break;
297 	    case AFMT_U16_BE:
298 		ct_func = trans->ct_u16be;
299 		break;
300 	    case AFMT_S16_LE:
301 		ct_func = trans->ct_s16le;
302 		break;
303 	    case AFMT_U16_LE:
304 		ct_func = trans->ct_u16le;
305 		break;
306 	    default:
307 		return 0;
308 	}
309 	/* if the user has requested a non-existent translation don't try
310 	   to call it but just return 0 bytes moved
311 	*/
312 	if (ct_func)
313 		return ct_func(userPtr, userCount, frame, frameUsed, frameLeft);
314 	return 0;
315 }
316 
317     /*
318      *  /dev/mixer abstraction
319      */
320 
321 static struct {
322     int busy;
323     int modify_counter;
324 } mixer;
325 
326 static int mixer_open(struct inode *inode, struct file *file)
327 {
328 	mutex_lock(&dmasound_core_mutex);
329 	if (!try_module_get(dmasound.mach.owner)) {
330 		mutex_unlock(&dmasound_core_mutex);
331 		return -ENODEV;
332 	}
333 	mixer.busy = 1;
334 	mutex_unlock(&dmasound_core_mutex);
335 	return 0;
336 }
337 
338 static int mixer_release(struct inode *inode, struct file *file)
339 {
340 	mutex_lock(&dmasound_core_mutex);
341 	mixer.busy = 0;
342 	module_put(dmasound.mach.owner);
343 	mutex_unlock(&dmasound_core_mutex);
344 	return 0;
345 }
346 
347 static int mixer_ioctl(struct file *file, u_int cmd, u_long arg)
348 {
349 	if (_SIOC_DIR(cmd) & _SIOC_WRITE)
350 	    mixer.modify_counter++;
351 	switch (cmd) {
352 	    case OSS_GETVERSION:
353 		return IOCTL_OUT(arg, SOUND_VERSION);
354 	    case SOUND_MIXER_INFO:
355 		{
356 		    mixer_info info;
357 		    memset(&info, 0, sizeof(info));
358 		    strscpy(info.id, dmasound.mach.name2, sizeof(info.id));
359 		    strscpy(info.name, dmasound.mach.name2, sizeof(info.name));
360 		    info.modify_counter = mixer.modify_counter;
361 		    if (copy_to_user((void __user *)arg, &info, sizeof(info)))
362 			    return -EFAULT;
363 		    return 0;
364 		}
365 	}
366 	if (dmasound.mach.mixer_ioctl)
367 	    return dmasound.mach.mixer_ioctl(cmd, arg);
368 	return -EINVAL;
369 }
370 
371 static long mixer_unlocked_ioctl(struct file *file, u_int cmd, u_long arg)
372 {
373 	int ret;
374 
375 	mutex_lock(&dmasound_core_mutex);
376 	ret = mixer_ioctl(file, cmd, arg);
377 	mutex_unlock(&dmasound_core_mutex);
378 
379 	return ret;
380 }
381 
382 static const struct file_operations mixer_fops =
383 {
384 	.owner		= THIS_MODULE,
385 	.llseek		= no_llseek,
386 	.unlocked_ioctl	= mixer_unlocked_ioctl,
387 	.compat_ioctl	= compat_ptr_ioctl,
388 	.open		= mixer_open,
389 	.release	= mixer_release,
390 };
391 
392 static void mixer_init(void)
393 {
394 #ifndef MODULE
395 	int mixer_unit;
396 #endif
397 	mixer_unit = register_sound_mixer(&mixer_fops, -1);
398 	if (mixer_unit < 0)
399 		return;
400 
401 	mixer.busy = 0;
402 	dmasound.treble = 0;
403 	dmasound.bass = 0;
404 	if (dmasound.mach.mixer_init)
405 	    dmasound.mach.mixer_init();
406 }
407 
408 
409     /*
410      *  Sound queue stuff, the heart of the driver
411      */
412 
413 struct sound_queue dmasound_write_sq;
414 static void sq_reset_output(void) ;
415 
416 static int sq_allocate_buffers(struct sound_queue *sq, int num, int size)
417 {
418 	int i;
419 
420 	if (sq->buffers)
421 		return 0;
422 	sq->numBufs = num;
423 	sq->bufSize = size;
424 	sq->buffers = kmalloc_array (num, sizeof(char *), GFP_KERNEL);
425 	if (!sq->buffers)
426 		return -ENOMEM;
427 	for (i = 0; i < num; i++) {
428 		sq->buffers[i] = dmasound.mach.dma_alloc(size, GFP_KERNEL);
429 		if (!sq->buffers[i]) {
430 			while (i--)
431 				dmasound.mach.dma_free(sq->buffers[i], size);
432 			kfree(sq->buffers);
433 			sq->buffers = NULL;
434 			return -ENOMEM;
435 		}
436 	}
437 	return 0;
438 }
439 
440 static void sq_release_buffers(struct sound_queue *sq)
441 {
442 	int i;
443 
444 	if (sq->buffers) {
445 		for (i = 0; i < sq->numBufs; i++)
446 			dmasound.mach.dma_free(sq->buffers[i], sq->bufSize);
447 		kfree(sq->buffers);
448 		sq->buffers = NULL;
449 	}
450 }
451 
452 
453 static int sq_setup(struct sound_queue *sq)
454 {
455 	int (*setup_func)(void) = NULL;
456 	int hard_frame ;
457 
458 	if (sq->locked) { /* are we already set? - and not changeable */
459 #ifdef DEBUG_DMASOUND
460 printk("dmasound_core: tried to sq_setup a locked queue\n") ;
461 #endif
462 		return -EINVAL ;
463 	}
464 	sq->locked = 1 ; /* don't think we have a race prob. here _check_ */
465 
466 	/* make sure that the parameters are set up
467 	   This should have been done already...
468 	*/
469 
470 	dmasound.mach.init();
471 
472 	/* OK.  If the user has set fragment parameters explicitly, then we
473 	   should leave them alone... as long as they are valid.
474 	   Invalid user fragment params can occur if we allow the whole buffer
475 	   to be used when the user requests the fragments sizes (with no soft
476 	   x-lation) and then the user subsequently sets a soft x-lation that
477 	   requires increased internal buffering.
478 
479 	   Othwerwise (if the user did not set them) OSS says that we should
480 	   select frag params on the basis of 0.5 s output & 0.1 s input
481 	   latency. (TODO.  For now we will copy in the defaults.)
482 	*/
483 
484 	if (sq->user_frags <= 0) {
485 		sq->max_count = sq->numBufs ;
486 		sq->max_active = sq->numBufs ;
487 		sq->block_size = sq->bufSize;
488 		/* set up the user info */
489 		sq->user_frags = sq->numBufs ;
490 		sq->user_frag_size = sq->bufSize ;
491 		sq->user_frag_size *=
492 			(dmasound.soft.size * (dmasound.soft.stereo+1) ) ;
493 		sq->user_frag_size /=
494 			(dmasound.hard.size * (dmasound.hard.stereo+1) ) ;
495 	} else {
496 		/* work out requested block size */
497 		sq->block_size = sq->user_frag_size ;
498 		sq->block_size *=
499 			(dmasound.hard.size * (dmasound.hard.stereo+1) ) ;
500 		sq->block_size /=
501 			(dmasound.soft.size * (dmasound.soft.stereo+1) ) ;
502 		/* the user wants to write frag-size chunks */
503 		sq->block_size *= dmasound.hard.speed ;
504 		sq->block_size /= dmasound.soft.speed ;
505 		/* this only works for size values which are powers of 2 */
506 		hard_frame =
507 			(dmasound.hard.size * (dmasound.hard.stereo+1))/8 ;
508 		sq->block_size +=  (hard_frame - 1) ;
509 		sq->block_size &= ~(hard_frame - 1) ; /* make sure we are aligned */
510 		/* let's just check for obvious mistakes */
511 		if ( sq->block_size <= 0 || sq->block_size > sq->bufSize) {
512 #ifdef DEBUG_DMASOUND
513 printk("dmasound_core: invalid frag size (user set %d)\n", sq->user_frag_size) ;
514 #endif
515 			sq->block_size = sq->bufSize ;
516 		}
517 		if ( sq->user_frags <= sq->numBufs ) {
518 			sq->max_count = sq->user_frags ;
519 			/* if user has set max_active - then use it */
520 			sq->max_active = (sq->max_active <= sq->max_count) ?
521 				sq->max_active : sq->max_count ;
522 		} else {
523 #ifdef DEBUG_DMASOUND
524 printk("dmasound_core: invalid frag count (user set %d)\n", sq->user_frags) ;
525 #endif
526 			sq->max_count =
527 			sq->max_active = sq->numBufs ;
528 		}
529 	}
530 	sq->front = sq->count = sq->rear_size = 0;
531 	sq->syncing = 0;
532 	sq->active = 0;
533 
534 	if (sq == &write_sq) {
535 	    sq->rear = -1;
536 	    setup_func = dmasound.mach.write_sq_setup;
537 	}
538 	if (setup_func)
539 	    return setup_func();
540 	return 0 ;
541 }
542 
543 static inline void sq_play(void)
544 {
545 	dmasound.mach.play();
546 }
547 
548 static ssize_t sq_write(struct file *file, const char __user *src, size_t uLeft,
549 			loff_t *ppos)
550 {
551 	ssize_t uWritten = 0;
552 	u_char *dest;
553 	ssize_t uUsed = 0, bUsed, bLeft;
554 	unsigned long flags ;
555 
556 	/* ++TeSche: Is something like this necessary?
557 	 * Hey, that's an honest question! Or does any other part of the
558 	 * filesystem already checks this situation? I really don't know.
559 	 */
560 	if (uLeft == 0)
561 		return 0;
562 
563 	/* implement any changes we have made to the soft/hard params.
564 	   this is not satisfactory really, all we have done up to now is to
565 	   say what we would like - there hasn't been any real checking of capability
566 	*/
567 
568 	if (shared_resources_initialised == 0) {
569 		dmasound.mach.init() ;
570 		shared_resources_initialised = 1 ;
571 	}
572 
573 	/* set up the sq if it is not already done. This may seem a dumb place
574 	   to do it - but it is what OSS requires.  It means that write() can
575 	   return memory allocation errors.  To avoid this possibility use the
576 	   GETBLKSIZE or GETOSPACE ioctls (after you've fiddled with all the
577 	   params you want to change) - these ioctls also force the setup.
578 	*/
579 
580 	if (write_sq.locked == 0) {
581 		if ((uWritten = sq_setup(&write_sq)) < 0) return uWritten ;
582 		uWritten = 0 ;
583 	}
584 
585 /* FIXME: I think that this may be the wrong behaviour when we get strapped
586 	for time and the cpu is close to being (or actually) behind in sending data.
587 	- because we've lost the time that the N samples, already in the buffer,
588 	would have given us to get here with the next lot from the user.
589 */
590 	/* The interrupt doesn't start to play the last, incomplete frame.
591 	 * Thus we can append to it without disabling the interrupts! (Note
592 	 * also that write_sq.rear isn't affected by the interrupt.)
593 	 */
594 
595 	/* as of 1.6 this behaviour changes if SNDCTL_DSP_POST has been issued:
596 	   this will mimic the behaviour of syncing and allow the sq_play() to
597 	   queue a partial fragment.  Since sq_play() may/will be called from
598 	   the IRQ handler - at least on Pmac we have to deal with it.
599 	   The strategy - possibly not optimum - is to kill _POST status if we
600 	   get here.  This seems, at least, reasonable - in the sense that POST
601 	   is supposed to indicate that we might not write before the queue
602 	   is drained - and if we get here in time then it does not apply.
603 	*/
604 
605 	spin_lock_irqsave(&dmasound.lock, flags);
606 	write_sq.syncing &= ~2 ; /* take out POST status */
607 	spin_unlock_irqrestore(&dmasound.lock, flags);
608 
609 	if (write_sq.count > 0 &&
610 	    (bLeft = write_sq.block_size-write_sq.rear_size) > 0) {
611 		dest = write_sq.buffers[write_sq.rear];
612 		bUsed = write_sq.rear_size;
613 		uUsed = sound_copy_translate(dmasound.trans_write, src, uLeft,
614 					     dest, &bUsed, bLeft);
615 		if (uUsed <= 0)
616 			return uUsed;
617 		src += uUsed;
618 		uWritten += uUsed;
619 		uLeft = (uUsed <= uLeft) ? (uLeft - uUsed) : 0 ; /* paranoia */
620 		write_sq.rear_size = bUsed;
621 	}
622 
623 	while (uLeft) {
624 		DEFINE_WAIT(wait);
625 
626 		while (write_sq.count >= write_sq.max_active) {
627 			prepare_to_wait(&write_sq.action_queue, &wait, TASK_INTERRUPTIBLE);
628 			sq_play();
629 			if (write_sq.non_blocking) {
630 				finish_wait(&write_sq.action_queue, &wait);
631 				return uWritten > 0 ? uWritten : -EAGAIN;
632 			}
633 			if (write_sq.count < write_sq.max_active)
634 				break;
635 
636 			schedule_timeout(HZ);
637 			if (signal_pending(current)) {
638 				finish_wait(&write_sq.action_queue, &wait);
639 				return uWritten > 0 ? uWritten : -EINTR;
640 			}
641 		}
642 
643 		finish_wait(&write_sq.action_queue, &wait);
644 
645 		/* Here, we can avoid disabling the interrupt by first
646 		 * copying and translating the data, and then updating
647 		 * the write_sq variables. Until this is done, the interrupt
648 		 * won't see the new frame and we can work on it
649 		 * undisturbed.
650 		 */
651 
652 		dest = write_sq.buffers[(write_sq.rear+1) % write_sq.max_count];
653 		bUsed = 0;
654 		bLeft = write_sq.block_size;
655 		uUsed = sound_copy_translate(dmasound.trans_write, src, uLeft,
656 					     dest, &bUsed, bLeft);
657 		if (uUsed <= 0)
658 			break;
659 		src += uUsed;
660 		uWritten += uUsed;
661 		uLeft = (uUsed <= uLeft) ? (uLeft - uUsed) : 0 ; /* paranoia */
662 		if (bUsed) {
663 			write_sq.rear = (write_sq.rear+1) % write_sq.max_count;
664 			write_sq.rear_size = bUsed;
665 			write_sq.count++;
666 		}
667 	} /* uUsed may have been 0 */
668 
669 	sq_play();
670 
671 	return uUsed < 0? uUsed: uWritten;
672 }
673 
674 static __poll_t sq_poll(struct file *file, struct poll_table_struct *wait)
675 {
676 	__poll_t mask = 0;
677 	int retVal;
678 
679 	if (write_sq.locked == 0) {
680 		if ((retVal = sq_setup(&write_sq)) < 0)
681 			return retVal;
682 		return 0;
683 	}
684 	if (file->f_mode & FMODE_WRITE )
685 		poll_wait(file, &write_sq.action_queue, wait);
686 	if (file->f_mode & FMODE_WRITE)
687 		if (write_sq.count < write_sq.max_active || write_sq.block_size - write_sq.rear_size > 0)
688 			mask |= EPOLLOUT | EPOLLWRNORM;
689 	return mask;
690 
691 }
692 
693 static inline void sq_init_waitqueue(struct sound_queue *sq)
694 {
695 	init_waitqueue_head(&sq->action_queue);
696 	init_waitqueue_head(&sq->open_queue);
697 	init_waitqueue_head(&sq->sync_queue);
698 	sq->busy = 0;
699 }
700 
701 #if 0 /* blocking open() */
702 static inline void sq_wake_up(struct sound_queue *sq, struct file *file,
703 			      fmode_t mode)
704 {
705 	if (file->f_mode & mode) {
706 		sq->busy = 0; /* CHECK: IS THIS OK??? */
707 		WAKE_UP(sq->open_queue);
708 	}
709 }
710 #endif
711 
712 static int sq_open2(struct sound_queue *sq, struct file *file, fmode_t mode,
713 		    int numbufs, int bufsize)
714 {
715 	int rc = 0;
716 
717 	if (file->f_mode & mode) {
718 		if (sq->busy) {
719 #if 0 /* blocking open() */
720 			rc = -EBUSY;
721 			if (file->f_flags & O_NONBLOCK)
722 				return rc;
723 			rc = -EINTR;
724 			if (wait_event_interruptible(sq->open_queue, !sq->busy))
725 				return rc;
726 			rc = 0;
727 #else
728 			/* OSS manual says we will return EBUSY regardless
729 			   of O_NOBLOCK.
730 			*/
731 			return -EBUSY ;
732 #endif
733 		}
734 		sq->busy = 1; /* Let's play spot-the-race-condition */
735 
736 		/* allocate the default number & size of buffers.
737 		   (i.e. specified in _setup() or as module params)
738 		   can't be changed at the moment - but _could_ be perhaps
739 		   in the setfragments ioctl.
740 		*/
741 		if (( rc = sq_allocate_buffers(sq, numbufs, bufsize))) {
742 #if 0 /* blocking open() */
743 			sq_wake_up(sq, file, mode);
744 #else
745 			sq->busy = 0 ;
746 #endif
747 			return rc;
748 		}
749 
750 		sq->non_blocking = file->f_flags & O_NONBLOCK;
751 	}
752 	return rc;
753 }
754 
755 #define write_sq_init_waitqueue()	sq_init_waitqueue(&write_sq)
756 #if 0 /* blocking open() */
757 #define write_sq_wake_up(file)		sq_wake_up(&write_sq, file, FMODE_WRITE)
758 #endif
759 #define write_sq_release_buffers()	sq_release_buffers(&write_sq)
760 #define write_sq_open(file)	\
761 	sq_open2(&write_sq, file, FMODE_WRITE, numWriteBufs, writeBufSize )
762 
763 static int sq_open(struct inode *inode, struct file *file)
764 {
765 	int rc;
766 
767 	mutex_lock(&dmasound_core_mutex);
768 	if (!try_module_get(dmasound.mach.owner)) {
769 		mutex_unlock(&dmasound_core_mutex);
770 		return -ENODEV;
771 	}
772 
773 	rc = write_sq_open(file); /* checks the f_mode */
774 	if (rc)
775 		goto out;
776 	if (file->f_mode & FMODE_READ) {
777 		/* TODO: if O_RDWR, release any resources grabbed by write part */
778 		rc = -ENXIO ; /* I think this is what is required by open(2) */
779 		goto out;
780 	}
781 
782 	if (dmasound.mach.sq_open)
783 	    dmasound.mach.sq_open(file->f_mode);
784 
785 	/* CHECK whether this is sensible - in the case that dsp0 could be opened
786 	  O_RDONLY and dsp1 could be opened O_WRONLY
787 	*/
788 
789 	dmasound.minDev = iminor(inode) & 0x0f;
790 
791 	/* OK. - we should make some attempt at consistency. At least the H'ware
792 	   options should be set with a valid mode.  We will make it that the LL
793 	   driver must supply defaults for hard & soft params.
794 	*/
795 
796 	if (shared_resource_owner == 0) {
797 		/* you can make this AFMT_U8/mono/8K if you want to mimic old
798 		   OSS behaviour - while we still have soft translations ;-) */
799 		dmasound.soft = dmasound.mach.default_soft ;
800 		dmasound.dsp = dmasound.mach.default_soft ;
801 		dmasound.hard = dmasound.mach.default_hard ;
802 	}
803 
804 #ifndef DMASOUND_STRICT_OSS_COMPLIANCE
805 	/* none of the current LL drivers can actually do this "native" at the moment
806 	   OSS does not really require us to supply /dev/audio if we can't do it.
807 	*/
808 	if (dmasound.minDev == SND_DEV_AUDIO) {
809 		sound_set_speed(8000);
810 		sound_set_stereo(0);
811 		sound_set_format(AFMT_MU_LAW);
812 	}
813 #endif
814 	mutex_unlock(&dmasound_core_mutex);
815 	return 0;
816  out:
817 	module_put(dmasound.mach.owner);
818 	mutex_unlock(&dmasound_core_mutex);
819 	return rc;
820 }
821 
822 static void sq_reset_output(void)
823 {
824 	sound_silence(); /* this _must_ stop DMA, we might be about to lose the buffers */
825 	write_sq.active = 0;
826 	write_sq.count = 0;
827 	write_sq.rear_size = 0;
828 	/* write_sq.front = (write_sq.rear+1) % write_sq.max_count;*/
829 	write_sq.front = 0 ;
830 	write_sq.rear = -1 ; /* same as for set-up */
831 
832 	/* OK - we can unlock the parameters and fragment settings */
833 	write_sq.locked = 0 ;
834 	write_sq.user_frags = 0 ;
835 	write_sq.user_frag_size = 0 ;
836 }
837 
838 static void sq_reset(void)
839 {
840 	sq_reset_output() ;
841 	/* we could consider resetting the shared_resources_owner here... but I
842 	   think it is probably still rather non-obvious to application writer
843 	*/
844 
845 	/* we release everything else though */
846 	shared_resources_initialised = 0 ;
847 }
848 
849 static int sq_fsync(void)
850 {
851 	int rc = 0;
852 	int timeout = 5;
853 
854 	write_sq.syncing |= 1;
855 	sq_play();	/* there may be an incomplete frame waiting */
856 
857 	while (write_sq.active) {
858 		wait_event_interruptible_timeout(write_sq.sync_queue,
859 						 !write_sq.active, HZ);
860 		if (signal_pending(current)) {
861 			/* While waiting for audio output to drain, an
862 			 * interrupt occurred.  Stop audio output immediately
863 			 * and clear the queue. */
864 			sq_reset_output();
865 			rc = -EINTR;
866 			break;
867 		}
868 		if (!--timeout) {
869 			printk(KERN_WARNING "dmasound: Timeout draining output\n");
870 			sq_reset_output();
871 			rc = -EIO;
872 			break;
873 		}
874 	}
875 
876 	/* flag no sync regardless of whether we had a DSP_POST or not */
877 	write_sq.syncing = 0 ;
878 	return rc;
879 }
880 
881 static int sq_release(struct inode *inode, struct file *file)
882 {
883 	int rc = 0;
884 
885 	mutex_lock(&dmasound_core_mutex);
886 
887 	if (file->f_mode & FMODE_WRITE) {
888 		if (write_sq.busy)
889 			rc = sq_fsync();
890 
891 		sq_reset_output() ; /* make sure dma is stopped and all is quiet */
892 		write_sq_release_buffers();
893 		write_sq.busy = 0;
894 	}
895 
896 	if (file->f_mode & shared_resource_owner) { /* it's us that has them */
897 		shared_resource_owner = 0 ;
898 		shared_resources_initialised = 0 ;
899 		dmasound.hard = dmasound.mach.default_hard ;
900 	}
901 
902 	module_put(dmasound.mach.owner);
903 
904 #if 0 /* blocking open() */
905 	/* Wake up a process waiting for the queue being released.
906 	 * Note: There may be several processes waiting for a call
907 	 * to open() returning. */
908 
909 	/* Iain: hmm I don't understand this next comment ... */
910 	/* There is probably a DOS atack here. They change the mode flag. */
911 	/* XXX add check here,*/
912 	read_sq_wake_up(file); /* checks f_mode */
913 	write_sq_wake_up(file); /* checks f_mode */
914 #endif /* blocking open() */
915 
916 	mutex_unlock(&dmasound_core_mutex);
917 
918 	return rc;
919 }
920 
921 /* here we see if we have a right to modify format, channels, size and so on
922    if no-one else has claimed it already then we do...
923 
924    TODO: We might change this to mask O_RDWR such that only one or the other channel
925    is the owner - if we have problems.
926 */
927 
928 static int shared_resources_are_mine(fmode_t md)
929 {
930 	if (shared_resource_owner)
931 		return (shared_resource_owner & md) != 0;
932 	else {
933 		shared_resource_owner = md ;
934 		return 1 ;
935 	}
936 }
937 
938 /* if either queue is locked we must deny the right to change shared params
939 */
940 
941 static int queues_are_quiescent(void)
942 {
943 	if (write_sq.locked)
944 		return 0 ;
945 	return 1 ;
946 }
947 
948 /* check and set a queue's fragments per user's wishes...
949    we will check against the pre-defined literals and the actual sizes.
950    This is a bit fraught - because soft translations can mess with our
951    buffer requirements *after* this call - OSS says "call setfrags first"
952 */
953 
954 /* It is possible to replace all the -EINVAL returns with an override that
955    just puts the allowable value in.  This may be what many OSS apps require
956 */
957 
958 static int set_queue_frags(struct sound_queue *sq, int bufs, int size)
959 {
960 	if (sq->locked) {
961 #ifdef DEBUG_DMASOUND
962 printk("dmasound_core: tried to set_queue_frags on a locked queue\n") ;
963 #endif
964 		return -EINVAL ;
965 	}
966 
967 	if ((size < MIN_FRAG_SIZE) || (size > MAX_FRAG_SIZE))
968 		return -EINVAL ;
969 	size = (1<<size) ; /* now in bytes */
970 	if (size > sq->bufSize)
971 		return -EINVAL ; /* this might still not work */
972 
973 	if (bufs <= 0)
974 		return -EINVAL ;
975 	if (bufs > sq->numBufs) /* the user is allowed say "don't care" with 0x7fff */
976 		bufs = sq->numBufs ;
977 
978 	/* there is, currently, no way to specify max_active separately
979 	   from max_count.  This could be a LL driver issue - I guess
980 	   if there is a requirement for these values to be different then
981 	  we will have to pass that info. up to this level.
982 	*/
983 	sq->user_frags =
984 	sq->max_active = bufs ;
985 	sq->user_frag_size = size ;
986 
987 	return 0 ;
988 }
989 
990 static int sq_ioctl(struct file *file, u_int cmd, u_long arg)
991 {
992 	int val, result;
993 	u_long fmt;
994 	int data;
995 	int size, nbufs;
996 	audio_buf_info info;
997 
998 	switch (cmd) {
999 	case SNDCTL_DSP_RESET:
1000 		sq_reset();
1001 		return 0;
1002 		break ;
1003 	case SNDCTL_DSP_GETFMTS:
1004 		fmt = dmasound.mach.hardware_afmts ; /* this is what OSS says.. */
1005 		return IOCTL_OUT(arg, fmt);
1006 		break ;
1007 	case SNDCTL_DSP_GETBLKSIZE:
1008 		/* this should tell the caller about bytes that the app can
1009 		   read/write - the app doesn't care about our internal buffers.
1010 		   We force sq_setup() here as per OSS 1.1 (which should
1011 		   compute the values necessary).
1012 		   Since there is no mechanism to specify read/write separately, for
1013 		   fds opened O_RDWR, the write_sq values will, arbitrarily, overwrite
1014 		   the read_sq ones.
1015 		*/
1016 		size = 0 ;
1017 		if (file->f_mode & FMODE_WRITE) {
1018 			if ( !write_sq.locked )
1019 				sq_setup(&write_sq) ;
1020 			size = write_sq.user_frag_size ;
1021 		}
1022 		return IOCTL_OUT(arg, size);
1023 		break ;
1024 	case SNDCTL_DSP_POST:
1025 		/* all we are going to do is to tell the LL that any
1026 		   partial frags can be queued for output.
1027 		   The LL will have to clear this flag when last output
1028 		   is queued.
1029 		*/
1030 		write_sq.syncing |= 0x2 ;
1031 		sq_play() ;
1032 		return 0 ;
1033 	case SNDCTL_DSP_SYNC:
1034 		/* This call, effectively, has the same behaviour as SNDCTL_DSP_RESET
1035 		   except that it waits for output to finish before resetting
1036 		   everything - read, however, is killed immediately.
1037 		*/
1038 		result = 0 ;
1039 		if (file->f_mode & FMODE_WRITE) {
1040 			result = sq_fsync();
1041 			sq_reset_output() ;
1042 		}
1043 		/* if we are the shared resource owner then release them */
1044 		if (file->f_mode & shared_resource_owner)
1045 			shared_resources_initialised = 0 ;
1046 		return result ;
1047 		break ;
1048 	case SOUND_PCM_READ_RATE:
1049 		return IOCTL_OUT(arg, dmasound.soft.speed);
1050 	case SNDCTL_DSP_SPEED:
1051 		/* changing this on the fly will have weird effects on the sound.
1052 		   Where there are rate conversions implemented in soft form - it
1053 		   will cause the _ctx_xxx() functions to be substituted.
1054 		   However, there doesn't appear to be any reason to dis-allow it from
1055 		   a driver pov.
1056 		*/
1057 		if (shared_resources_are_mine(file->f_mode)) {
1058 			IOCTL_IN(arg, data);
1059 			data = sound_set_speed(data) ;
1060 			shared_resources_initialised = 0 ;
1061 			return IOCTL_OUT(arg, data);
1062 		} else
1063 			return -EINVAL ;
1064 		break ;
1065 	/* OSS says these next 4 actions are undefined when the device is
1066 	   busy/active - we will just return -EINVAL.
1067 	   To be allowed to change one - (a) you have to own the right
1068 	    (b) the queue(s) must be quiescent
1069 	*/
1070 	case SNDCTL_DSP_STEREO:
1071 		if (shared_resources_are_mine(file->f_mode) &&
1072 		    queues_are_quiescent()) {
1073 			IOCTL_IN(arg, data);
1074 			shared_resources_initialised = 0 ;
1075 			return IOCTL_OUT(arg, sound_set_stereo(data));
1076 		} else
1077 			return -EINVAL ;
1078 		break ;
1079 	case SOUND_PCM_WRITE_CHANNELS:
1080 		if (shared_resources_are_mine(file->f_mode) &&
1081 		    queues_are_quiescent()) {
1082 			IOCTL_IN(arg, data);
1083 			/* the user might ask for 20 channels, we will return 1 or 2 */
1084 			shared_resources_initialised = 0 ;
1085 			return IOCTL_OUT(arg, sound_set_stereo(data-1)+1);
1086 		} else
1087 			return -EINVAL ;
1088 		break ;
1089 	case SNDCTL_DSP_SETFMT:
1090 		if (shared_resources_are_mine(file->f_mode) &&
1091 		    queues_are_quiescent()) {
1092 		    	int format;
1093 			IOCTL_IN(arg, data);
1094 			shared_resources_initialised = 0 ;
1095 			format = sound_set_format(data);
1096 			result = IOCTL_OUT(arg, format);
1097 			if (result < 0)
1098 				return result;
1099 			if (format != data && data != AFMT_QUERY)
1100 				return -EINVAL;
1101 			return 0;
1102 		} else
1103 			return -EINVAL ;
1104 	case SNDCTL_DSP_SUBDIVIDE:
1105 		return -EINVAL ;
1106 	case SNDCTL_DSP_SETFRAGMENT:
1107 		/* we can do this independently for the two queues - with the
1108 		   proviso that for fds opened O_RDWR we cannot separate the
1109 		   actions and both queues will be set per the last call.
1110 		   NOTE: this does *NOT* actually set the queue up - merely
1111 		   registers our intentions.
1112 		*/
1113 		IOCTL_IN(arg, data);
1114 		result = 0 ;
1115 		nbufs = (data >> 16) & 0x7fff ; /* 0x7fff is 'use maximum' */
1116 		size = data & 0xffff;
1117 		if (file->f_mode & FMODE_WRITE) {
1118 			result = set_queue_frags(&write_sq, nbufs, size) ;
1119 			if (result)
1120 				return result ;
1121 		}
1122 		/* NOTE: this return value is irrelevant - OSS specifically says that
1123 		   the value is 'random' and that the user _must_ check the actual
1124 		   frags values using SNDCTL_DSP_GETBLKSIZE or similar */
1125 		return IOCTL_OUT(arg, data);
1126 		break ;
1127 	case SNDCTL_DSP_GETOSPACE:
1128 		/*
1129 		*/
1130 		if (file->f_mode & FMODE_WRITE) {
1131 			if ( !write_sq.locked )
1132 				sq_setup(&write_sq) ;
1133 			info.fragments = write_sq.max_active - write_sq.count;
1134 			info.fragstotal = write_sq.max_active;
1135 			info.fragsize = write_sq.user_frag_size;
1136 			info.bytes = info.fragments * info.fragsize;
1137 			if (copy_to_user((void __user *)arg, &info, sizeof(info)))
1138 				return -EFAULT;
1139 			return 0;
1140 		} else
1141 			return -EINVAL ;
1142 		break ;
1143 	case SNDCTL_DSP_GETCAPS:
1144 		val = dmasound.mach.capabilities & 0xffffff00;
1145 		return IOCTL_OUT(arg,val);
1146 
1147 	default:
1148 		return mixer_ioctl(file, cmd, arg);
1149 	}
1150 	return -EINVAL;
1151 }
1152 
1153 static long sq_unlocked_ioctl(struct file *file, u_int cmd, u_long arg)
1154 {
1155 	int ret;
1156 
1157 	mutex_lock(&dmasound_core_mutex);
1158 	ret = sq_ioctl(file, cmd, arg);
1159 	mutex_unlock(&dmasound_core_mutex);
1160 
1161 	return ret;
1162 }
1163 
1164 static const struct file_operations sq_fops =
1165 {
1166 	.owner		= THIS_MODULE,
1167 	.llseek		= no_llseek,
1168 	.write		= sq_write,
1169 	.poll		= sq_poll,
1170 	.unlocked_ioctl	= sq_unlocked_ioctl,
1171 	.compat_ioctl	= compat_ptr_ioctl,
1172 	.open		= sq_open,
1173 	.release	= sq_release,
1174 };
1175 
1176 static int sq_init(void)
1177 {
1178 	const struct file_operations *fops = &sq_fops;
1179 #ifndef MODULE
1180 	int sq_unit;
1181 #endif
1182 
1183 	sq_unit = register_sound_dsp(fops, -1);
1184 	if (sq_unit < 0) {
1185 		printk(KERN_ERR "dmasound_core: couldn't register fops\n") ;
1186 		return sq_unit ;
1187 	}
1188 
1189 	write_sq_init_waitqueue();
1190 
1191 	/* These parameters will be restored for every clean open()
1192 	 * in the case of multiple open()s (e.g. dsp0 & dsp1) they
1193 	 * will be set so long as the shared resources have no owner.
1194 	 */
1195 
1196 	if (shared_resource_owner == 0) {
1197 		dmasound.soft = dmasound.mach.default_soft ;
1198 		dmasound.hard = dmasound.mach.default_hard ;
1199 		dmasound.dsp = dmasound.mach.default_soft ;
1200 		shared_resources_initialised = 0 ;
1201 	}
1202 	return 0 ;
1203 }
1204 
1205 
1206     /*
1207      *  /dev/sndstat
1208      */
1209 
1210 /* we allow more space for record-enabled because there are extra output lines.
1211    the number here must include the amount we are prepared to give to the low-level
1212    driver.
1213 */
1214 
1215 #define STAT_BUFF_LEN 768
1216 
1217 /* this is how much space we will allow the low-level driver to use
1218    in the stat buffer.  Currently, 2 * (80 character line + <NL>).
1219    We do not police this (it is up to the ll driver to be honest).
1220 */
1221 
1222 #define LOW_LEVEL_STAT_ALLOC 162
1223 
1224 static struct {
1225     int busy;
1226     char buf[STAT_BUFF_LEN];	/* state.buf should not overflow! */
1227     int len, ptr;
1228 } state;
1229 
1230 /* publish this function for use by low-level code, if required */
1231 
1232 static char *get_afmt_string(int afmt)
1233 {
1234         switch(afmt) {
1235             case AFMT_MU_LAW:
1236                 return "mu-law";
1237                 break;
1238             case AFMT_A_LAW:
1239                 return "A-law";
1240                 break;
1241             case AFMT_U8:
1242                 return "unsigned 8 bit";
1243                 break;
1244             case AFMT_S8:
1245                 return "signed 8 bit";
1246                 break;
1247             case AFMT_S16_BE:
1248                 return "signed 16 bit BE";
1249                 break;
1250             case AFMT_U16_BE:
1251                 return "unsigned 16 bit BE";
1252                 break;
1253             case AFMT_S16_LE:
1254                 return "signed 16 bit LE";
1255                 break;
1256             case AFMT_U16_LE:
1257                 return "unsigned 16 bit LE";
1258                 break;
1259 	    case 0:
1260 		return "format not set" ;
1261 		break ;
1262             default:
1263                 break ;
1264         }
1265         return "ERROR: Unsupported AFMT_XXXX code" ;
1266 }
1267 
1268 static int state_open(struct inode *inode, struct file *file)
1269 {
1270 	char *buffer = state.buf;
1271 	int len = 0;
1272 	int ret;
1273 
1274 	mutex_lock(&dmasound_core_mutex);
1275 	ret = -EBUSY;
1276 	if (state.busy)
1277 		goto out;
1278 
1279 	ret = -ENODEV;
1280 	if (!try_module_get(dmasound.mach.owner))
1281 		goto out;
1282 
1283 	state.ptr = 0;
1284 	state.busy = 1;
1285 
1286 	len += sprintf(buffer+len, "%sDMA sound driver rev %03d :\n",
1287 		dmasound.mach.name, (DMASOUND_CORE_REVISION<<4) +
1288 		((dmasound.mach.version>>8) & 0x0f));
1289 	len += sprintf(buffer+len,
1290 		"Core driver edition %02d.%02d : %s driver edition %02d.%02d\n",
1291 		DMASOUND_CORE_REVISION, DMASOUND_CORE_EDITION, dmasound.mach.name2,
1292 		(dmasound.mach.version >> 8), (dmasound.mach.version & 0xff)) ;
1293 
1294 	/* call the low-level module to fill in any stat info. that it has
1295 	   if present.  Maximum buffer usage is specified.
1296 	*/
1297 
1298 	if (dmasound.mach.state_info)
1299 		len += dmasound.mach.state_info(buffer+len,
1300 			(size_t) LOW_LEVEL_STAT_ALLOC) ;
1301 
1302 	/* make usage of the state buffer as deterministic as poss.
1303 	   exceptional conditions could cause overrun - and this is flagged as
1304 	   a kernel error.
1305 	*/
1306 
1307 	/* formats and settings */
1308 
1309 	len += sprintf(buffer+len,"\t\t === Formats & settings ===\n") ;
1310 	len += sprintf(buffer+len,"Parameter %20s%20s\n","soft","hard") ;
1311 	len += sprintf(buffer+len,"Format   :%20s%20s\n",
1312 		get_afmt_string(dmasound.soft.format),
1313 		get_afmt_string(dmasound.hard.format));
1314 
1315 	len += sprintf(buffer+len,"Samp Rate:%14d s/sec%14d s/sec\n",
1316 		       dmasound.soft.speed, dmasound.hard.speed);
1317 
1318 	len += sprintf(buffer+len,"Channels :%20s%20s\n",
1319 		       dmasound.soft.stereo ? "stereo" : "mono",
1320 		       dmasound.hard.stereo ? "stereo" : "mono" );
1321 
1322 	/* sound queue status */
1323 
1324 	len += sprintf(buffer+len,"\t\t === Sound Queue status ===\n");
1325 	len += sprintf(buffer+len,"Allocated:%8s%6s\n","Buffers","Size") ;
1326 	len += sprintf(buffer+len,"%9s:%8d%6d\n",
1327 		"write", write_sq.numBufs, write_sq.bufSize) ;
1328 	len += sprintf(buffer+len,
1329 		"Current  : MaxFrg FragSiz MaxAct Frnt Rear "
1330 		"Cnt RrSize A B S L  xruns\n") ;
1331 	len += sprintf(buffer+len,"%9s:%7d%8d%7d%5d%5d%4d%7d%2d%2d%2d%2d%7d\n",
1332 		"write", write_sq.max_count, write_sq.block_size,
1333 		write_sq.max_active, write_sq.front, write_sq.rear,
1334 		write_sq.count, write_sq.rear_size, write_sq.active,
1335 		write_sq.busy, write_sq.syncing, write_sq.locked, write_sq.xruns) ;
1336 #ifdef DEBUG_DMASOUND
1337 printk("dmasound: stat buffer used %d bytes\n", len) ;
1338 #endif
1339 
1340 	if (len >= STAT_BUFF_LEN)
1341 		printk(KERN_ERR "dmasound_core: stat buffer overflowed!\n");
1342 
1343 	state.len = len;
1344 	ret = 0;
1345 out:
1346 	mutex_unlock(&dmasound_core_mutex);
1347 	return ret;
1348 }
1349 
1350 static int state_release(struct inode *inode, struct file *file)
1351 {
1352 	mutex_lock(&dmasound_core_mutex);
1353 	state.busy = 0;
1354 	module_put(dmasound.mach.owner);
1355 	mutex_unlock(&dmasound_core_mutex);
1356 	return 0;
1357 }
1358 
1359 static ssize_t state_read(struct file *file, char __user *buf, size_t count,
1360 			  loff_t *ppos)
1361 {
1362 	int n = state.len - state.ptr;
1363 	if (n > count)
1364 		n = count;
1365 	if (n <= 0)
1366 		return 0;
1367 	if (copy_to_user(buf, &state.buf[state.ptr], n))
1368 		return -EFAULT;
1369 	state.ptr += n;
1370 	return n;
1371 }
1372 
1373 static const struct file_operations state_fops = {
1374 	.owner		= THIS_MODULE,
1375 	.llseek		= no_llseek,
1376 	.read		= state_read,
1377 	.open		= state_open,
1378 	.release	= state_release,
1379 };
1380 
1381 static int state_init(void)
1382 {
1383 #ifndef MODULE
1384 	int state_unit;
1385 #endif
1386 	state_unit = register_sound_special(&state_fops, SND_DEV_STATUS);
1387 	if (state_unit < 0)
1388 		return state_unit ;
1389 	state.busy = 0;
1390 	return 0 ;
1391 }
1392 
1393 
1394     /*
1395      *  Config & Setup
1396      *
1397      *  This function is called by _one_ chipset-specific driver
1398      */
1399 
1400 int dmasound_init(void)
1401 {
1402 	int res ;
1403 #ifdef MODULE
1404 	if (irq_installed)
1405 		return -EBUSY;
1406 #endif
1407 
1408 	/* Set up sound queue, /dev/audio and /dev/dsp. */
1409 
1410 	/* Set default settings. */
1411 	if ((res = sq_init()) < 0)
1412 		return res ;
1413 
1414 	/* Set up /dev/sndstat. */
1415 	if ((res = state_init()) < 0)
1416 		return res ;
1417 
1418 	/* Set up /dev/mixer. */
1419 	mixer_init();
1420 
1421 	if (!dmasound.mach.irqinit()) {
1422 		printk(KERN_ERR "DMA sound driver: Interrupt initialization failed\n");
1423 		return -ENODEV;
1424 	}
1425 #ifdef MODULE
1426 	irq_installed = 1;
1427 #endif
1428 
1429 	printk(KERN_INFO "%s DMA sound driver rev %03d installed\n",
1430 		dmasound.mach.name, (DMASOUND_CORE_REVISION<<4) +
1431 		((dmasound.mach.version>>8) & 0x0f));
1432 	printk(KERN_INFO
1433 		"Core driver edition %02d.%02d : %s driver edition %02d.%02d\n",
1434 		DMASOUND_CORE_REVISION, DMASOUND_CORE_EDITION, dmasound.mach.name2,
1435 		(dmasound.mach.version >> 8), (dmasound.mach.version & 0xff)) ;
1436 	printk(KERN_INFO "Write will use %4d fragments of %7d bytes as default\n",
1437 		numWriteBufs, writeBufSize) ;
1438 	return 0;
1439 }
1440 
1441 #ifdef MODULE
1442 
1443 void dmasound_deinit(void)
1444 {
1445 	if (irq_installed) {
1446 		sound_silence();
1447 		dmasound.mach.irqcleanup();
1448 		irq_installed = 0;
1449 	}
1450 
1451 	write_sq_release_buffers();
1452 
1453 	if (mixer_unit >= 0)
1454 		unregister_sound_mixer(mixer_unit);
1455 	if (state_unit >= 0)
1456 		unregister_sound_special(state_unit);
1457 	if (sq_unit >= 0)
1458 		unregister_sound_dsp(sq_unit);
1459 }
1460 
1461 #else /* !MODULE */
1462 
1463 static int dmasound_setup(char *str)
1464 {
1465 	int ints[6], size;
1466 
1467 	str = get_options(str, ARRAY_SIZE(ints), ints);
1468 
1469 	/* check the bootstrap parameter for "dmasound=" */
1470 
1471 	/* FIXME: other than in the most naive of cases there is no sense in these
1472 	 *	  buffers being other than powers of two.  This is not checked yet.
1473 	 */
1474 
1475 	switch (ints[0]) {
1476 	case 3:
1477 		if ((ints[3] < 0) || (ints[3] > MAX_CATCH_RADIUS))
1478 			printk("dmasound_setup: invalid catch radius, using default = %d\n", catchRadius);
1479 		else
1480 			catchRadius = ints[3];
1481 		fallthrough;
1482 	case 2:
1483 		if (ints[1] < MIN_BUFFERS)
1484 			printk("dmasound_setup: invalid number of buffers, using default = %d\n", numWriteBufs);
1485 		else
1486 			numWriteBufs = ints[1];
1487 		fallthrough;
1488 	case 1:
1489 		if ((size = ints[2]) < 256) /* check for small buffer specs */
1490 			size <<= 10 ;
1491                 if (size < MIN_BUFSIZE || size > MAX_BUFSIZE)
1492                         printk("dmasound_setup: invalid write buffer size, using default = %d\n", writeBufSize);
1493                 else
1494                         writeBufSize = size;
1495 	case 0:
1496 		break;
1497 	default:
1498 		printk("dmasound_setup: invalid number of arguments\n");
1499 		return 0;
1500 	}
1501 	return 1;
1502 }
1503 
1504 __setup("dmasound=", dmasound_setup);
1505 
1506 #endif /* !MODULE */
1507 
1508     /*
1509      *  Conversion tables
1510      */
1511 
1512 #ifdef HAS_8BIT_TABLES
1513 /* 8 bit mu-law */
1514 
1515 char dmasound_ulaw2dma8[] = {
1516 	-126,	-122,	-118,	-114,	-110,	-106,	-102,	-98,
1517 	-94,	-90,	-86,	-82,	-78,	-74,	-70,	-66,
1518 	-63,	-61,	-59,	-57,	-55,	-53,	-51,	-49,
1519 	-47,	-45,	-43,	-41,	-39,	-37,	-35,	-33,
1520 	-31,	-30,	-29,	-28,	-27,	-26,	-25,	-24,
1521 	-23,	-22,	-21,	-20,	-19,	-18,	-17,	-16,
1522 	-16,	-15,	-15,	-14,	-14,	-13,	-13,	-12,
1523 	-12,	-11,	-11,	-10,	-10,	-9,	-9,	-8,
1524 	-8,	-8,	-7,	-7,	-7,	-7,	-6,	-6,
1525 	-6,	-6,	-5,	-5,	-5,	-5,	-4,	-4,
1526 	-4,	-4,	-4,	-4,	-3,	-3,	-3,	-3,
1527 	-3,	-3,	-3,	-3,	-2,	-2,	-2,	-2,
1528 	-2,	-2,	-2,	-2,	-2,	-2,	-2,	-2,
1529 	-1,	-1,	-1,	-1,	-1,	-1,	-1,	-1,
1530 	-1,	-1,	-1,	-1,	-1,	-1,	-1,	-1,
1531 	-1,	-1,	-1,	-1,	-1,	-1,	-1,	0,
1532 	125,	121,	117,	113,	109,	105,	101,	97,
1533 	93,	89,	85,	81,	77,	73,	69,	65,
1534 	62,	60,	58,	56,	54,	52,	50,	48,
1535 	46,	44,	42,	40,	38,	36,	34,	32,
1536 	30,	29,	28,	27,	26,	25,	24,	23,
1537 	22,	21,	20,	19,	18,	17,	16,	15,
1538 	15,	14,	14,	13,	13,	12,	12,	11,
1539 	11,	10,	10,	9,	9,	8,	8,	7,
1540 	7,	7,	6,	6,	6,	6,	5,	5,
1541 	5,	5,	4,	4,	4,	4,	3,	3,
1542 	3,	3,	3,	3,	2,	2,	2,	2,
1543 	2,	2,	2,	2,	1,	1,	1,	1,
1544 	1,	1,	1,	1,	1,	1,	1,	1,
1545 	0,	0,	0,	0,	0,	0,	0,	0,
1546 	0,	0,	0,	0,	0,	0,	0,	0,
1547 	0,	0,	0,	0,	0,	0,	0,	0
1548 };
1549 
1550 /* 8 bit A-law */
1551 
1552 char dmasound_alaw2dma8[] = {
1553 	-22,	-21,	-24,	-23,	-18,	-17,	-20,	-19,
1554 	-30,	-29,	-32,	-31,	-26,	-25,	-28,	-27,
1555 	-11,	-11,	-12,	-12,	-9,	-9,	-10,	-10,
1556 	-15,	-15,	-16,	-16,	-13,	-13,	-14,	-14,
1557 	-86,	-82,	-94,	-90,	-70,	-66,	-78,	-74,
1558 	-118,	-114,	-126,	-122,	-102,	-98,	-110,	-106,
1559 	-43,	-41,	-47,	-45,	-35,	-33,	-39,	-37,
1560 	-59,	-57,	-63,	-61,	-51,	-49,	-55,	-53,
1561 	-2,	-2,	-2,	-2,	-2,	-2,	-2,	-2,
1562 	-2,	-2,	-2,	-2,	-2,	-2,	-2,	-2,
1563 	-1,	-1,	-1,	-1,	-1,	-1,	-1,	-1,
1564 	-1,	-1,	-1,	-1,	-1,	-1,	-1,	-1,
1565 	-6,	-6,	-6,	-6,	-5,	-5,	-5,	-5,
1566 	-8,	-8,	-8,	-8,	-7,	-7,	-7,	-7,
1567 	-3,	-3,	-3,	-3,	-3,	-3,	-3,	-3,
1568 	-4,	-4,	-4,	-4,	-4,	-4,	-4,	-4,
1569 	21,	20,	23,	22,	17,	16,	19,	18,
1570 	29,	28,	31,	30,	25,	24,	27,	26,
1571 	10,	10,	11,	11,	8,	8,	9,	9,
1572 	14,	14,	15,	15,	12,	12,	13,	13,
1573 	86,	82,	94,	90,	70,	66,	78,	74,
1574 	118,	114,	126,	122,	102,	98,	110,	106,
1575 	43,	41,	47,	45,	35,	33,	39,	37,
1576 	59,	57,	63,	61,	51,	49,	55,	53,
1577 	1,	1,	1,	1,	1,	1,	1,	1,
1578 	1,	1,	1,	1,	1,	1,	1,	1,
1579 	0,	0,	0,	0,	0,	0,	0,	0,
1580 	0,	0,	0,	0,	0,	0,	0,	0,
1581 	5,	5,	5,	5,	4,	4,	4,	4,
1582 	7,	7,	7,	7,	6,	6,	6,	6,
1583 	2,	2,	2,	2,	2,	2,	2,	2,
1584 	3,	3,	3,	3,	3,	3,	3,	3
1585 };
1586 #endif /* HAS_8BIT_TABLES */
1587 
1588     /*
1589      *  Visible symbols for modules
1590      */
1591 
1592 EXPORT_SYMBOL(dmasound);
1593 EXPORT_SYMBOL(dmasound_init);
1594 #ifdef MODULE
1595 EXPORT_SYMBOL(dmasound_deinit);
1596 #endif
1597 EXPORT_SYMBOL(dmasound_write_sq);
1598 EXPORT_SYMBOL(dmasound_catchRadius);
1599 #ifdef HAS_8BIT_TABLES
1600 EXPORT_SYMBOL(dmasound_ulaw2dma8);
1601 EXPORT_SYMBOL(dmasound_alaw2dma8);
1602 #endif
1603