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