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