1/*
2 * sound/oss/dmabuf.c
3 *
4 * The DMA buffer manager for digitized voice applications
5 */
6/*
7 * Copyright (C) by Hannu Savolainen 1993-1997
8 *
9 * OSS/Free for Linux is distributed under the GNU GENERAL PUBLIC LICENSE (GPL)
10 * Version 2 (June 1991). See the "COPYING" file distributed with this software
11 * for more info.
12 *
13 * Thomas Sailer   : moved several static variables into struct audio_operations
14 *                   (which is grossly misnamed btw.) because they have the same
15 *                   lifetime as the rest in there and dynamic allocation saves
16 *                   12k or so
17 * Thomas Sailer   : remove {in,out}_sleep_flag. It was used for the sleeper to
18 *                   determine if it was woken up by the expiring timeout or by
19 *                   an explicit wake_up. The return value from schedule_timeout
20 *		     can be used instead; if 0, the wakeup was due to the timeout.
21 *
22 * Rob Riggs		Added persistent DMA buffers (1998/10/17)
23 */
24
25#define BE_CONSERVATIVE
26#define SAMPLE_ROUNDUP 0
27
28#include <linux/mm.h>
29#include <linux/gfp.h>
30#include "sound_config.h"
31#include "sleep.h"
32
33#define DMAP_FREE_ON_CLOSE      0
34#define DMAP_KEEP_ON_CLOSE      1
35extern int sound_dmap_flag;
36
37static void dma_reset_output(int dev);
38static void dma_reset_input(int dev);
39static int local_start_dma(struct audio_operations *adev, unsigned long physaddr, int count, int dma_mode);
40
41
42
43static int debugmem;    	/* switched off by default */
44static int dma_buffsize = DSP_BUFFSIZE;
45
46static long dmabuf_timeout(struct dma_buffparms *dmap)
47{
48	long tmout;
49
50	tmout = (dmap->fragment_size * HZ) / dmap->data_rate;
51	tmout += HZ / 5;	/* Some safety distance */
52	if (tmout < (HZ / 2))
53		tmout = HZ / 2;
54	if (tmout > 20 * HZ)
55		tmout = 20 * HZ;
56	return tmout;
57}
58
59static int sound_alloc_dmap(struct dma_buffparms *dmap)
60{
61	char *start_addr, *end_addr;
62	int dma_pagesize;
63	int sz, size;
64	struct page *page;
65
66	dmap->mapping_flags &= ~DMA_MAP_MAPPED;
67
68	if (dmap->raw_buf != NULL)
69		return 0;	/* Already done */
70	if (dma_buffsize < 4096)
71		dma_buffsize = 4096;
72	dma_pagesize = (dmap->dma < 4) ? (64 * 1024) : (128 * 1024);
73
74	/*
75	 *	Now check for the Cyrix problem.
76	 */
77
78	if(isa_dma_bridge_buggy==2)
79		dma_pagesize=32768;
80
81	dmap->raw_buf = NULL;
82	dmap->buffsize = dma_buffsize;
83	if (dmap->buffsize > dma_pagesize)
84		dmap->buffsize = dma_pagesize;
85	start_addr = NULL;
86	/*
87	 * Now loop until we get a free buffer. Try to get smaller buffer if
88	 * it fails. Don't accept smaller than 8k buffer for performance
89	 * reasons.
90	 */
91	while (start_addr == NULL && dmap->buffsize > PAGE_SIZE) {
92		for (sz = 0, size = PAGE_SIZE; size < dmap->buffsize; sz++, size <<= 1);
93		dmap->buffsize = PAGE_SIZE * (1 << sz);
94		start_addr = (char *) __get_free_pages(GFP_ATOMIC|GFP_DMA|__GFP_NOWARN, sz);
95		if (start_addr == NULL)
96			dmap->buffsize /= 2;
97	}
98
99	if (start_addr == NULL) {
100		printk(KERN_WARNING "Sound error: Couldn't allocate DMA buffer\n");
101		return -ENOMEM;
102	} else {
103		/* make some checks */
104		end_addr = start_addr + dmap->buffsize - 1;
105
106		if (debugmem)
107			printk(KERN_DEBUG "sound: start 0x%lx, end 0x%lx\n", (long) start_addr, (long) end_addr);
108
109		/* now check if it fits into the same dma-pagesize */
110
111		if (((long) start_addr & ~(dma_pagesize - 1)) != ((long) end_addr & ~(dma_pagesize - 1))
112		    || end_addr >= (char *) (MAX_DMA_ADDRESS)) {
113			printk(KERN_ERR "sound: Got invalid address 0x%lx for %db DMA-buffer\n", (long) start_addr, dmap->buffsize);
114			return -EFAULT;
115		}
116	}
117	dmap->raw_buf = start_addr;
118	dmap->raw_buf_phys = dma_map_single(NULL, start_addr, dmap->buffsize, DMA_BIDIRECTIONAL);
119
120	for (page = virt_to_page(start_addr); page <= virt_to_page(end_addr); page++)
121		SetPageReserved(page);
122	return 0;
123}
124
125static void sound_free_dmap(struct dma_buffparms *dmap)
126{
127	int sz, size;
128	struct page *page;
129	unsigned long start_addr, end_addr;
130
131	if (dmap->raw_buf == NULL)
132		return;
133	if (dmap->mapping_flags & DMA_MAP_MAPPED)
134		return;		/* Don't free mmapped buffer. Will use it next time */
135	for (sz = 0, size = PAGE_SIZE; size < dmap->buffsize; sz++, size <<= 1);
136
137	start_addr = (unsigned long) dmap->raw_buf;
138	end_addr = start_addr + dmap->buffsize;
139
140	for (page = virt_to_page(start_addr); page <= virt_to_page(end_addr); page++)
141		ClearPageReserved(page);
142
143	dma_unmap_single(NULL, dmap->raw_buf_phys, dmap->buffsize, DMA_BIDIRECTIONAL);
144	free_pages((unsigned long) dmap->raw_buf, sz);
145	dmap->raw_buf = NULL;
146}
147
148
149/* Intel version !!!!!!!!! */
150
151static int sound_start_dma(struct dma_buffparms *dmap, unsigned long physaddr, int count, int dma_mode)
152{
153	unsigned long flags;
154	int chan = dmap->dma;
155
156	/* printk( "Start DMA%d %d, %d\n",  chan,  (int)(physaddr-dmap->raw_buf_phys),  count); */
157
158	flags = claim_dma_lock();
159	disable_dma(chan);
160	clear_dma_ff(chan);
161	set_dma_mode(chan, dma_mode);
162	set_dma_addr(chan, physaddr);
163	set_dma_count(chan, count);
164	enable_dma(chan);
165	release_dma_lock(flags);
166
167	return 0;
168}
169
170static void dma_init_buffers(struct dma_buffparms *dmap)
171{
172	dmap->qlen = dmap->qhead = dmap->qtail = dmap->user_counter = 0;
173	dmap->byte_counter = 0;
174	dmap->max_byte_counter = 8000 * 60 * 60;
175	dmap->bytes_in_use = dmap->buffsize;
176
177	dmap->dma_mode = DMODE_NONE;
178	dmap->mapping_flags = 0;
179	dmap->neutral_byte = 0x80;
180	dmap->data_rate = 8000;
181	dmap->cfrag = -1;
182	dmap->closing = 0;
183	dmap->nbufs = 1;
184	dmap->flags = DMA_BUSY;	/* Other flags off */
185}
186
187static int open_dmap(struct audio_operations *adev, int mode, struct dma_buffparms *dmap)
188{
189	int err;
190
191	if (dmap->flags & DMA_BUSY)
192		return -EBUSY;
193	if ((err = sound_alloc_dmap(dmap)) < 0)
194		return err;
195
196	if (dmap->raw_buf == NULL) {
197		printk(KERN_WARNING "Sound: DMA buffers not available\n");
198		return -ENOSPC;	/* Memory allocation failed during boot */
199	}
200	if (dmap->dma >= 0 && sound_open_dma(dmap->dma, adev->name)) {
201		printk(KERN_WARNING "Unable to grab(2) DMA%d for the audio driver\n", dmap->dma);
202		return -EBUSY;
203	}
204	dma_init_buffers(dmap);
205	spin_lock_init(&dmap->lock);
206	dmap->open_mode = mode;
207	dmap->subdivision = dmap->underrun_count = 0;
208	dmap->fragment_size = 0;
209	dmap->max_fragments = 65536;	/* Just a large value */
210	dmap->byte_counter = 0;
211	dmap->max_byte_counter = 8000 * 60 * 60;
212	dmap->applic_profile = APF_NORMAL;
213	dmap->needs_reorg = 1;
214	dmap->audio_callback = NULL;
215	dmap->callback_parm = 0;
216	return 0;
217}
218
219static void close_dmap(struct audio_operations *adev, struct dma_buffparms *dmap)
220{
221	unsigned long flags;
222
223	if (dmap->dma >= 0) {
224		sound_close_dma(dmap->dma);
225		flags=claim_dma_lock();
226		disable_dma(dmap->dma);
227		release_dma_lock(flags);
228	}
229	if (dmap->flags & DMA_BUSY)
230		dmap->dma_mode = DMODE_NONE;
231	dmap->flags &= ~DMA_BUSY;
232
233	if (sound_dmap_flag == DMAP_FREE_ON_CLOSE)
234		sound_free_dmap(dmap);
235}
236
237
238static unsigned int default_set_bits(int dev, unsigned int bits)
239{
240	mm_segment_t fs = get_fs();
241
242	set_fs(get_ds());
243	audio_devs[dev]->d->ioctl(dev, SNDCTL_DSP_SETFMT, (void __user *)&bits);
244	set_fs(fs);
245	return bits;
246}
247
248static int default_set_speed(int dev, int speed)
249{
250	mm_segment_t fs = get_fs();
251
252	set_fs(get_ds());
253	audio_devs[dev]->d->ioctl(dev, SNDCTL_DSP_SPEED, (void __user *)&speed);
254	set_fs(fs);
255	return speed;
256}
257
258static short default_set_channels(int dev, short channels)
259{
260	int c = channels;
261	mm_segment_t fs = get_fs();
262
263	set_fs(get_ds());
264	audio_devs[dev]->d->ioctl(dev, SNDCTL_DSP_CHANNELS, (void __user *)&c);
265	set_fs(fs);
266	return c;
267}
268
269static void check_driver(struct audio_driver *d)
270{
271	if (d->set_speed == NULL)
272		d->set_speed = default_set_speed;
273	if (d->set_bits == NULL)
274		d->set_bits = default_set_bits;
275	if (d->set_channels == NULL)
276		d->set_channels = default_set_channels;
277}
278
279int DMAbuf_open(int dev, int mode)
280{
281	struct audio_operations *adev = audio_devs[dev];
282	int retval;
283	struct dma_buffparms *dmap_in = NULL;
284	struct dma_buffparms *dmap_out = NULL;
285
286	if (!adev)
287		  return -ENXIO;
288	if (!(adev->flags & DMA_DUPLEX))
289		adev->dmap_in = adev->dmap_out;
290	check_driver(adev->d);
291
292	if ((retval = adev->d->open(dev, mode)) < 0)
293		return retval;
294	dmap_out = adev->dmap_out;
295	dmap_in = adev->dmap_in;
296	if (dmap_in == dmap_out)
297		adev->flags &= ~DMA_DUPLEX;
298
299	if (mode & OPEN_WRITE) {
300		if ((retval = open_dmap(adev, mode, dmap_out)) < 0) {
301			adev->d->close(dev);
302			return retval;
303		}
304	}
305	adev->enable_bits = mode;
306
307	if (mode == OPEN_READ || (mode != OPEN_WRITE && (adev->flags & DMA_DUPLEX))) {
308		if ((retval = open_dmap(adev, mode, dmap_in)) < 0) {
309			adev->d->close(dev);
310			if (mode & OPEN_WRITE)
311				close_dmap(adev, dmap_out);
312			return retval;
313		}
314	}
315	adev->open_mode = mode;
316	adev->go = 1;
317
318	adev->d->set_bits(dev, 8);
319	adev->d->set_channels(dev, 1);
320	adev->d->set_speed(dev, DSP_DEFAULT_SPEED);
321	if (adev->dmap_out->dma_mode == DMODE_OUTPUT)
322		memset(adev->dmap_out->raw_buf, adev->dmap_out->neutral_byte,
323		       adev->dmap_out->bytes_in_use);
324	return 0;
325}
326/* MUST not hold the spinlock */
327void DMAbuf_reset(int dev)
328{
329	if (audio_devs[dev]->open_mode & OPEN_WRITE)
330		dma_reset_output(dev);
331
332	if (audio_devs[dev]->open_mode & OPEN_READ)
333		dma_reset_input(dev);
334}
335
336static void dma_reset_output(int dev)
337{
338	struct audio_operations *adev = audio_devs[dev];
339	unsigned long flags,f ;
340	struct dma_buffparms *dmap = adev->dmap_out;
341
342	if (!(dmap->flags & DMA_STARTED))	/* DMA is not active */
343		return;
344
345	/*
346	 *	First wait until the current fragment has been played completely
347	 */
348	spin_lock_irqsave(&dmap->lock,flags);
349	adev->dmap_out->flags |= DMA_SYNCING;
350
351	adev->dmap_out->underrun_count = 0;
352	if (!signal_pending(current) && adev->dmap_out->qlen &&
353	    adev->dmap_out->underrun_count == 0){
354		spin_unlock_irqrestore(&dmap->lock,flags);
355		oss_broken_sleep_on(&adev->out_sleeper, dmabuf_timeout(dmap));
356		spin_lock_irqsave(&dmap->lock,flags);
357	}
358	adev->dmap_out->flags &= ~(DMA_SYNCING | DMA_ACTIVE);
359
360	/*
361	 *	Finally shut the device off
362	 */
363	if (!(adev->flags & DMA_DUPLEX) || !adev->d->halt_output)
364		adev->d->halt_io(dev);
365	else
366		adev->d->halt_output(dev);
367	adev->dmap_out->flags &= ~DMA_STARTED;
368
369	f=claim_dma_lock();
370	clear_dma_ff(dmap->dma);
371	disable_dma(dmap->dma);
372	release_dma_lock(f);
373
374	dmap->byte_counter = 0;
375	reorganize_buffers(dev, adev->dmap_out, 0);
376	dmap->qlen = dmap->qhead = dmap->qtail = dmap->user_counter = 0;
377	spin_unlock_irqrestore(&dmap->lock,flags);
378}
379
380static void dma_reset_input(int dev)
381{
382        struct audio_operations *adev = audio_devs[dev];
383	unsigned long flags;
384	struct dma_buffparms *dmap = adev->dmap_in;
385
386	spin_lock_irqsave(&dmap->lock,flags);
387	if (!(adev->flags & DMA_DUPLEX) || !adev->d->halt_input)
388		adev->d->halt_io(dev);
389	else
390		adev->d->halt_input(dev);
391	adev->dmap_in->flags &= ~DMA_STARTED;
392
393	dmap->qlen = dmap->qhead = dmap->qtail = dmap->user_counter = 0;
394	dmap->byte_counter = 0;
395	reorganize_buffers(dev, adev->dmap_in, 1);
396	spin_unlock_irqrestore(&dmap->lock,flags);
397}
398/* MUST be called with holding the dmap->lock */
399void DMAbuf_launch_output(int dev, struct dma_buffparms *dmap)
400{
401	struct audio_operations *adev = audio_devs[dev];
402
403	if (!((adev->enable_bits * adev->go) & PCM_ENABLE_OUTPUT))
404		return;		/* Don't start DMA yet */
405	dmap->dma_mode = DMODE_OUTPUT;
406
407	if (!(dmap->flags & DMA_ACTIVE) || !(adev->flags & DMA_AUTOMODE) || (dmap->flags & DMA_NODMA)) {
408		if (!(dmap->flags & DMA_STARTED)) {
409			reorganize_buffers(dev, dmap, 0);
410			if (adev->d->prepare_for_output(dev, dmap->fragment_size, dmap->nbufs))
411				return;
412			if (!(dmap->flags & DMA_NODMA))
413				local_start_dma(adev, dmap->raw_buf_phys, dmap->bytes_in_use,DMA_MODE_WRITE);
414			dmap->flags |= DMA_STARTED;
415		}
416		if (dmap->counts[dmap->qhead] == 0)
417			dmap->counts[dmap->qhead] = dmap->fragment_size;
418		dmap->dma_mode = DMODE_OUTPUT;
419		adev->d->output_block(dev, dmap->raw_buf_phys + dmap->qhead * dmap->fragment_size,
420				      dmap->counts[dmap->qhead], 1);
421		if (adev->d->trigger)
422			adev->d->trigger(dev,adev->enable_bits * adev->go);
423	}
424	dmap->flags |= DMA_ACTIVE;
425}
426
427int DMAbuf_sync(int dev)
428{
429	struct audio_operations *adev = audio_devs[dev];
430	unsigned long flags;
431	int n = 0;
432	struct dma_buffparms *dmap;
433
434	if (!adev->go && !(adev->enable_bits & PCM_ENABLE_OUTPUT))
435		return 0;
436
437	if (adev->dmap_out->dma_mode == DMODE_OUTPUT) {
438		dmap = adev->dmap_out;
439		spin_lock_irqsave(&dmap->lock,flags);
440		if (dmap->qlen > 0 && !(dmap->flags & DMA_ACTIVE))
441			DMAbuf_launch_output(dev, dmap);
442		adev->dmap_out->flags |= DMA_SYNCING;
443		adev->dmap_out->underrun_count = 0;
444		while (!signal_pending(current) && n++ < adev->dmap_out->nbufs &&
445		       adev->dmap_out->qlen && adev->dmap_out->underrun_count == 0) {
446			long t = dmabuf_timeout(dmap);
447			spin_unlock_irqrestore(&dmap->lock,flags);
448			/* FIXME: not safe may miss events */
449			t = oss_broken_sleep_on(&adev->out_sleeper, t);
450			spin_lock_irqsave(&dmap->lock,flags);
451			if (!t) {
452				adev->dmap_out->flags &= ~DMA_SYNCING;
453				spin_unlock_irqrestore(&dmap->lock,flags);
454				return adev->dmap_out->qlen;
455			}
456		}
457		adev->dmap_out->flags &= ~(DMA_SYNCING | DMA_ACTIVE);
458
459		/*
460		 * Some devices such as GUS have huge amount of on board RAM for the
461		 * audio data. We have to wait until the device has finished playing.
462		 */
463
464		/* still holding the lock */
465		if (adev->d->local_qlen) {   /* Device has hidden buffers */
466			while (!signal_pending(current) &&
467			       adev->d->local_qlen(dev)){
468				spin_unlock_irqrestore(&dmap->lock,flags);
469				oss_broken_sleep_on(&adev->out_sleeper,
470							       dmabuf_timeout(dmap));
471				spin_lock_irqsave(&dmap->lock,flags);
472			}
473		}
474		spin_unlock_irqrestore(&dmap->lock,flags);
475	}
476	adev->dmap_out->dma_mode = DMODE_NONE;
477	return adev->dmap_out->qlen;
478}
479
480int DMAbuf_release(int dev, int mode)
481{
482	struct audio_operations *adev = audio_devs[dev];
483	struct dma_buffparms *dmap;
484	unsigned long flags;
485
486	dmap = adev->dmap_out;
487	if (adev->open_mode & OPEN_WRITE)
488		adev->dmap_out->closing = 1;
489
490	if (adev->open_mode & OPEN_READ){
491		adev->dmap_in->closing = 1;
492		dmap = adev->dmap_in;
493	}
494	if (adev->open_mode & OPEN_WRITE)
495		if (!(adev->dmap_out->mapping_flags & DMA_MAP_MAPPED))
496			if (!signal_pending(current) && (adev->dmap_out->dma_mode == DMODE_OUTPUT))
497				DMAbuf_sync(dev);
498	if (adev->dmap_out->dma_mode == DMODE_OUTPUT)
499		memset(adev->dmap_out->raw_buf, adev->dmap_out->neutral_byte, adev->dmap_out->bytes_in_use);
500
501	DMAbuf_reset(dev);
502	spin_lock_irqsave(&dmap->lock,flags);
503	adev->d->close(dev);
504
505	if (adev->open_mode & OPEN_WRITE)
506		close_dmap(adev, adev->dmap_out);
507
508	if (adev->open_mode == OPEN_READ ||
509	    (adev->open_mode != OPEN_WRITE &&
510	     (adev->flags & DMA_DUPLEX)))
511		close_dmap(adev, adev->dmap_in);
512	adev->open_mode = 0;
513	spin_unlock_irqrestore(&dmap->lock,flags);
514	return 0;
515}
516/* called with dmap->lock dold */
517int DMAbuf_activate_recording(int dev, struct dma_buffparms *dmap)
518{
519	struct audio_operations *adev = audio_devs[dev];
520	int  err;
521
522	if (!(adev->open_mode & OPEN_READ))
523		return 0;
524	if (!(adev->enable_bits & PCM_ENABLE_INPUT))
525		return 0;
526	if (dmap->dma_mode == DMODE_OUTPUT) {	/* Direction change */
527		/* release lock - it's not recursive */
528		spin_unlock_irq(&dmap->lock);
529		DMAbuf_sync(dev);
530		DMAbuf_reset(dev);
531		spin_lock_irq(&dmap->lock);
532		dmap->dma_mode = DMODE_NONE;
533	}
534	if (!dmap->dma_mode) {
535		reorganize_buffers(dev, dmap, 1);
536		if ((err = adev->d->prepare_for_input(dev,
537				dmap->fragment_size, dmap->nbufs)) < 0)
538			return err;
539		dmap->dma_mode = DMODE_INPUT;
540	}
541	if (!(dmap->flags & DMA_ACTIVE)) {
542		if (dmap->needs_reorg)
543			reorganize_buffers(dev, dmap, 0);
544		local_start_dma(adev, dmap->raw_buf_phys, dmap->bytes_in_use, DMA_MODE_READ);
545		adev->d->start_input(dev, dmap->raw_buf_phys + dmap->qtail * dmap->fragment_size,
546				     dmap->fragment_size, 0);
547		dmap->flags |= DMA_ACTIVE;
548		if (adev->d->trigger)
549			adev->d->trigger(dev, adev->enable_bits * adev->go);
550	}
551	return 0;
552}
553/* acquires lock */
554int DMAbuf_getrdbuffer(int dev, char **buf, int *len, int dontblock)
555{
556	struct audio_operations *adev = audio_devs[dev];
557	unsigned long flags;
558	int err = 0, n = 0;
559	struct dma_buffparms *dmap = adev->dmap_in;
560
561	if (!(adev->open_mode & OPEN_READ))
562		return -EIO;
563	spin_lock_irqsave(&dmap->lock,flags);
564	if (dmap->needs_reorg)
565		reorganize_buffers(dev, dmap, 0);
566	if (adev->dmap_in->mapping_flags & DMA_MAP_MAPPED) {
567/*		  printk(KERN_WARNING "Sound: Can't read from mmapped device (1)\n");*/
568		  spin_unlock_irqrestore(&dmap->lock,flags);
569		  return -EINVAL;
570	} else while (dmap->qlen <= 0 && n++ < 10) {
571		long timeout = MAX_SCHEDULE_TIMEOUT;
572		if (!(adev->enable_bits & PCM_ENABLE_INPUT) || !adev->go) {
573			spin_unlock_irqrestore(&dmap->lock,flags);
574			return -EAGAIN;
575		}
576		if ((err = DMAbuf_activate_recording(dev, dmap)) < 0) {
577			spin_unlock_irqrestore(&dmap->lock,flags);
578			return err;
579		}
580		/* Wait for the next block */
581
582		if (dontblock) {
583			spin_unlock_irqrestore(&dmap->lock,flags);
584			return -EAGAIN;
585		}
586		if (adev->go)
587			timeout = dmabuf_timeout(dmap);
588
589		spin_unlock_irqrestore(&dmap->lock,flags);
590		timeout = oss_broken_sleep_on(&adev->in_sleeper, timeout);
591		if (!timeout) {
592			/* FIXME: include device name */
593			err = -EIO;
594			printk(KERN_WARNING "Sound: DMA (input) timed out - IRQ/DRQ config error?\n");
595			dma_reset_input(dev);
596		} else
597			err = -EINTR;
598		spin_lock_irqsave(&dmap->lock,flags);
599	}
600	spin_unlock_irqrestore(&dmap->lock,flags);
601
602	if (dmap->qlen <= 0)
603		return err ? err : -EINTR;
604	*buf = &dmap->raw_buf[dmap->qhead * dmap->fragment_size + dmap->counts[dmap->qhead]];
605	*len = dmap->fragment_size - dmap->counts[dmap->qhead];
606
607	return dmap->qhead;
608}
609
610int DMAbuf_rmchars(int dev, int buff_no, int c)
611{
612	struct audio_operations *adev = audio_devs[dev];
613	struct dma_buffparms *dmap = adev->dmap_in;
614	int p = dmap->counts[dmap->qhead] + c;
615
616	if (dmap->mapping_flags & DMA_MAP_MAPPED)
617	{
618/*		  printk("Sound: Can't read from mmapped device (2)\n");*/
619		return -EINVAL;
620	}
621	else if (dmap->qlen <= 0)
622		return -EIO;
623	else if (p >= dmap->fragment_size) {  /* This buffer is completely empty */
624		dmap->counts[dmap->qhead] = 0;
625		dmap->qlen--;
626		dmap->qhead = (dmap->qhead + 1) % dmap->nbufs;
627	}
628	else dmap->counts[dmap->qhead] = p;
629
630	return 0;
631}
632/* MUST be called with dmap->lock hold */
633int DMAbuf_get_buffer_pointer(int dev, struct dma_buffparms *dmap, int direction)
634{
635	/*
636	 *	Try to approximate the active byte position of the DMA pointer within the
637	 *	buffer area as well as possible.
638	 */
639
640	int pos;
641	unsigned long f;
642
643	if (!(dmap->flags & DMA_ACTIVE))
644		pos = 0;
645	else {
646		int chan = dmap->dma;
647
648		f=claim_dma_lock();
649		clear_dma_ff(chan);
650
651		if(!isa_dma_bridge_buggy)
652			disable_dma(dmap->dma);
653
654		pos = get_dma_residue(chan);
655
656		pos = dmap->bytes_in_use - pos;
657
658		if (!(dmap->mapping_flags & DMA_MAP_MAPPED)) {
659			if (direction == DMODE_OUTPUT) {
660				if (dmap->qhead == 0)
661					if (pos > dmap->fragment_size)
662						pos = 0;
663			} else {
664				if (dmap->qtail == 0)
665					if (pos > dmap->fragment_size)
666						pos = 0;
667			}
668		}
669		if (pos < 0)
670			pos = 0;
671		if (pos >= dmap->bytes_in_use)
672			pos = 0;
673
674		if(!isa_dma_bridge_buggy)
675			enable_dma(dmap->dma);
676
677		release_dma_lock(f);
678	}
679	/* printk( "%04x ",  pos); */
680
681	return pos;
682}
683
684/*
685 *	DMAbuf_start_devices() is called by the /dev/music driver to start
686 *	one or more audio devices at desired moment.
687 */
688
689void DMAbuf_start_devices(unsigned int devmask)
690{
691	struct audio_operations *adev;
692	int dev;
693
694	for (dev = 0; dev < num_audiodevs; dev++) {
695		if (!(devmask & (1 << dev)))
696			continue;
697		if (!(adev = audio_devs[dev]))
698			continue;
699		if (adev->open_mode == 0)
700			continue;
701		if (adev->go)
702			continue;
703		/* OK to start the device */
704		adev->go = 1;
705		if (adev->d->trigger)
706			adev->d->trigger(dev,adev->enable_bits * adev->go);
707	}
708}
709/* via poll called without a lock ?*/
710int DMAbuf_space_in_queue(int dev)
711{
712	struct audio_operations *adev = audio_devs[dev];
713	int len, max, tmp;
714	struct dma_buffparms *dmap = adev->dmap_out;
715	int lim = dmap->nbufs;
716
717	if (lim < 2)
718		lim = 2;
719
720	if (dmap->qlen >= lim)	/* No space at all */
721		return 0;
722
723	/*
724	 *	Verify that there are no more pending buffers than the limit
725	 *	defined by the process.
726	 */
727
728	max = dmap->max_fragments;
729	if (max > lim)
730		max = lim;
731	len = dmap->qlen;
732
733	if (adev->d->local_qlen) {
734		tmp = adev->d->local_qlen(dev);
735		if (tmp && len)
736			tmp--;	/* This buffer has been counted twice */
737		len += tmp;
738	}
739	if (dmap->byte_counter % dmap->fragment_size)	/* There is a partial fragment */
740		len = len + 1;
741
742	if (len >= max)
743		return 0;
744	return max - len;
745}
746/* MUST not hold the spinlock  - this function may sleep */
747static int output_sleep(int dev, int dontblock)
748{
749	struct audio_operations *adev = audio_devs[dev];
750	int err = 0;
751	struct dma_buffparms *dmap = adev->dmap_out;
752	long timeout;
753	long timeout_value;
754
755	if (dontblock)
756		return -EAGAIN;
757	if (!(adev->enable_bits & PCM_ENABLE_OUTPUT))
758		return -EAGAIN;
759
760	/*
761	 * Wait for free space
762	 */
763	if (signal_pending(current))
764		return -EINTR;
765	timeout = (adev->go && !(dmap->flags & DMA_NOTIMEOUT));
766	if (timeout)
767		timeout_value = dmabuf_timeout(dmap);
768	else
769		timeout_value = MAX_SCHEDULE_TIMEOUT;
770	timeout_value = oss_broken_sleep_on(&adev->out_sleeper, timeout_value);
771	if (timeout != MAX_SCHEDULE_TIMEOUT && !timeout_value) {
772		printk(KERN_WARNING "Sound: DMA (output) timed out - IRQ/DRQ config error?\n");
773		dma_reset_output(dev);
774	} else {
775		if (signal_pending(current))
776			err = -EINTR;
777	}
778	return err;
779}
780/* called with the lock held */
781static int find_output_space(int dev, char **buf, int *size)
782{
783	struct audio_operations *adev = audio_devs[dev];
784	struct dma_buffparms *dmap = adev->dmap_out;
785	unsigned long active_offs;
786	long len, offs;
787	int maxfrags;
788	int occupied_bytes = (dmap->user_counter % dmap->fragment_size);
789
790	*buf = dmap->raw_buf;
791	if (!(maxfrags = DMAbuf_space_in_queue(dev)) && !occupied_bytes)
792		return 0;
793
794#ifdef BE_CONSERVATIVE
795	active_offs = dmap->byte_counter + dmap->qhead * dmap->fragment_size;
796#else
797	active_offs = max(DMAbuf_get_buffer_pointer(dev, dmap, DMODE_OUTPUT), 0);
798	/* Check for pointer wrapping situation */
799	if (active_offs >= dmap->bytes_in_use)
800		active_offs = 0;
801	active_offs += dmap->byte_counter;
802#endif
803
804	offs = (dmap->user_counter % dmap->bytes_in_use) & ~SAMPLE_ROUNDUP;
805	if (offs < 0 || offs >= dmap->bytes_in_use) {
806		printk(KERN_ERR "Sound: Got unexpected offs %ld. Giving up.\n", offs);
807		printk("Counter = %ld, bytes=%d\n", dmap->user_counter, dmap->bytes_in_use);
808		return 0;
809	}
810	*buf = dmap->raw_buf + offs;
811
812	len = active_offs + dmap->bytes_in_use - dmap->user_counter;	/* Number of unused bytes in buffer */
813
814	if ((offs + len) > dmap->bytes_in_use)
815		len = dmap->bytes_in_use - offs;
816	if (len < 0) {
817		return 0;
818	}
819	if (len > ((maxfrags * dmap->fragment_size) - occupied_bytes))
820		len = (maxfrags * dmap->fragment_size) - occupied_bytes;
821	*size = len & ~SAMPLE_ROUNDUP;
822	return (*size > 0);
823}
824/* acquires lock  */
825int DMAbuf_getwrbuffer(int dev, char **buf, int *size, int dontblock)
826{
827	struct audio_operations *adev = audio_devs[dev];
828	unsigned long flags;
829	int err = -EIO;
830	struct dma_buffparms *dmap = adev->dmap_out;
831
832	if (dmap->mapping_flags & DMA_MAP_MAPPED) {
833/*		printk(KERN_DEBUG "Sound: Can't write to mmapped device (3)\n");*/
834		return -EINVAL;
835	}
836	spin_lock_irqsave(&dmap->lock,flags);
837	if (dmap->needs_reorg)
838		reorganize_buffers(dev, dmap, 0);
839
840	if (dmap->dma_mode == DMODE_INPUT) {	/* Direction change */
841		spin_unlock_irqrestore(&dmap->lock,flags);
842		DMAbuf_reset(dev);
843		spin_lock_irqsave(&dmap->lock,flags);
844	}
845	dmap->dma_mode = DMODE_OUTPUT;
846
847	while (find_output_space(dev, buf, size) <= 0) {
848		spin_unlock_irqrestore(&dmap->lock,flags);
849		if ((err = output_sleep(dev, dontblock)) < 0) {
850			return err;
851		}
852		spin_lock_irqsave(&dmap->lock,flags);
853	}
854
855	spin_unlock_irqrestore(&dmap->lock,flags);
856	return 0;
857}
858/* has to acquire dmap->lock */
859int DMAbuf_move_wrpointer(int dev, int l)
860{
861	struct audio_operations *adev = audio_devs[dev];
862	struct dma_buffparms *dmap = adev->dmap_out;
863	unsigned long ptr;
864	unsigned long end_ptr, p;
865	int post;
866	unsigned long flags;
867
868	spin_lock_irqsave(&dmap->lock,flags);
869	post= (dmap->flags & DMA_POST);
870	ptr = (dmap->user_counter / dmap->fragment_size) * dmap->fragment_size;
871
872	dmap->flags &= ~DMA_POST;
873	dmap->cfrag = -1;
874	dmap->user_counter += l;
875	dmap->flags |= DMA_DIRTY;
876
877	if (dmap->byte_counter >= dmap->max_byte_counter) {
878		/* Wrap the byte counters */
879		long decr = dmap->byte_counter;
880		dmap->byte_counter = (dmap->byte_counter % dmap->bytes_in_use);
881		decr -= dmap->byte_counter;
882		dmap->user_counter -= decr;
883	}
884	end_ptr = (dmap->user_counter / dmap->fragment_size) * dmap->fragment_size;
885
886	p = (dmap->user_counter - 1) % dmap->bytes_in_use;
887	dmap->neutral_byte = dmap->raw_buf[p];
888
889	/* Update the fragment based bookkeeping too */
890	while (ptr < end_ptr) {
891		dmap->counts[dmap->qtail] = dmap->fragment_size;
892		dmap->qtail = (dmap->qtail + 1) % dmap->nbufs;
893		dmap->qlen++;
894		ptr += dmap->fragment_size;
895	}
896
897	dmap->counts[dmap->qtail] = dmap->user_counter - ptr;
898
899	/*
900	 *	Let the low level driver perform some postprocessing to
901	 *	the written data.
902	 */
903	if (adev->d->postprocess_write)
904		adev->d->postprocess_write(dev);
905
906	if (!(dmap->flags & DMA_ACTIVE))
907		if (dmap->qlen > 1 || (dmap->qlen > 0 && (post || dmap->qlen >= dmap->nbufs - 1)))
908			DMAbuf_launch_output(dev, dmap);
909
910	spin_unlock_irqrestore(&dmap->lock,flags);
911	return 0;
912}
913
914int DMAbuf_start_dma(int dev, unsigned long physaddr, int count, int dma_mode)
915{
916	struct audio_operations *adev = audio_devs[dev];
917	struct dma_buffparms *dmap = (dma_mode == DMA_MODE_WRITE) ? adev->dmap_out : adev->dmap_in;
918
919	if (dmap->raw_buf == NULL) {
920		printk(KERN_ERR "sound: DMA buffer(1) == NULL\n");
921		printk("Device %d, chn=%s\n", dev, (dmap == adev->dmap_out) ? "out" : "in");
922		return 0;
923	}
924	if (dmap->dma < 0)
925		return 0;
926	sound_start_dma(dmap, physaddr, count, dma_mode);
927	return count;
928}
929EXPORT_SYMBOL(DMAbuf_start_dma);
930
931static int local_start_dma(struct audio_operations *adev, unsigned long physaddr, int count, int dma_mode)
932{
933	struct dma_buffparms *dmap = (dma_mode == DMA_MODE_WRITE) ? adev->dmap_out : adev->dmap_in;
934
935	if (dmap->raw_buf == NULL) {
936		printk(KERN_ERR "sound: DMA buffer(2) == NULL\n");
937		printk(KERN_ERR "Device %s, chn=%s\n", adev->name, (dmap == adev->dmap_out) ? "out" : "in");
938		return 0;
939	}
940	if (dmap->flags & DMA_NODMA)
941		return 1;
942	if (dmap->dma < 0)
943		return 0;
944	sound_start_dma(dmap, dmap->raw_buf_phys, dmap->bytes_in_use, dma_mode | DMA_AUTOINIT);
945	dmap->flags |= DMA_STARTED;
946	return count;
947}
948
949static void finish_output_interrupt(int dev, struct dma_buffparms *dmap)
950{
951	struct audio_operations *adev = audio_devs[dev];
952
953	if (dmap->audio_callback != NULL)
954		dmap->audio_callback(dev, dmap->callback_parm);
955	wake_up(&adev->out_sleeper);
956	wake_up(&adev->poll_sleeper);
957}
958/* called with dmap->lock held in irq context*/
959static void do_outputintr(int dev, int dummy)
960{
961	struct audio_operations *adev = audio_devs[dev];
962	struct dma_buffparms *dmap = adev->dmap_out;
963	int this_fragment;
964
965	if (dmap->raw_buf == NULL) {
966		printk(KERN_ERR "Sound: Error. Audio interrupt (%d) after freeing buffers.\n", dev);
967		return;
968	}
969	if (dmap->mapping_flags & DMA_MAP_MAPPED) {	/* Virtual memory mapped access */
970		/* mmapped access */
971		dmap->qhead = (dmap->qhead + 1) % dmap->nbufs;
972		if (dmap->qhead == 0) {	    /* Wrapped */
973			dmap->byte_counter += dmap->bytes_in_use;
974			if (dmap->byte_counter >= dmap->max_byte_counter) {	/* Overflow */
975				long decr = dmap->byte_counter;
976				dmap->byte_counter = (dmap->byte_counter % dmap->bytes_in_use);
977				decr -= dmap->byte_counter;
978				dmap->user_counter -= decr;
979			}
980		}
981		dmap->qlen++;	/* Yes increment it (don't decrement) */
982		if (!(adev->flags & DMA_AUTOMODE))
983			dmap->flags &= ~DMA_ACTIVE;
984		dmap->counts[dmap->qhead] = dmap->fragment_size;
985		DMAbuf_launch_output(dev, dmap);
986		finish_output_interrupt(dev, dmap);
987		return;
988	}
989
990	dmap->qlen--;
991	this_fragment = dmap->qhead;
992	dmap->qhead = (dmap->qhead + 1) % dmap->nbufs;
993
994	if (dmap->qhead == 0) {	/* Wrapped */
995		dmap->byte_counter += dmap->bytes_in_use;
996		if (dmap->byte_counter >= dmap->max_byte_counter) {	/* Overflow */
997			long decr = dmap->byte_counter;
998			dmap->byte_counter = (dmap->byte_counter % dmap->bytes_in_use);
999			decr -= dmap->byte_counter;
1000			dmap->user_counter -= decr;
1001		}
1002	}
1003	if (!(adev->flags & DMA_AUTOMODE))
1004		dmap->flags &= ~DMA_ACTIVE;
1005
1006	/*
1007	 *	This is  dmap->qlen <= 0 except when closing when
1008	 *	dmap->qlen < 0
1009	 */
1010
1011	while (dmap->qlen <= -dmap->closing) {
1012		dmap->underrun_count++;
1013		dmap->qlen++;
1014		if ((dmap->flags & DMA_DIRTY) && dmap->applic_profile != APF_CPUINTENS) {
1015			dmap->flags &= ~DMA_DIRTY;
1016			memset(adev->dmap_out->raw_buf, adev->dmap_out->neutral_byte,
1017			       adev->dmap_out->buffsize);
1018		}
1019		dmap->user_counter += dmap->fragment_size;
1020		dmap->qtail = (dmap->qtail + 1) % dmap->nbufs;
1021	}
1022	if (dmap->qlen > 0)
1023		DMAbuf_launch_output(dev, dmap);
1024	finish_output_interrupt(dev, dmap);
1025}
1026/* called in irq context */
1027void DMAbuf_outputintr(int dev, int notify_only)
1028{
1029	struct audio_operations *adev = audio_devs[dev];
1030	unsigned long flags;
1031	struct dma_buffparms *dmap = adev->dmap_out;
1032
1033	spin_lock_irqsave(&dmap->lock,flags);
1034	if (!(dmap->flags & DMA_NODMA)) {
1035		int chan = dmap->dma, pos, n;
1036		unsigned long f;
1037
1038		f=claim_dma_lock();
1039
1040		if(!isa_dma_bridge_buggy)
1041			disable_dma(dmap->dma);
1042		clear_dma_ff(chan);
1043		pos = dmap->bytes_in_use - get_dma_residue(chan);
1044		if(!isa_dma_bridge_buggy)
1045			enable_dma(dmap->dma);
1046		release_dma_lock(f);
1047
1048		pos = pos / dmap->fragment_size;	/* Actual qhead */
1049		if (pos < 0 || pos >= dmap->nbufs)
1050			pos = 0;
1051		n = 0;
1052		while (dmap->qhead != pos && n++ < dmap->nbufs)
1053			do_outputintr(dev, notify_only);
1054	}
1055	else
1056		do_outputintr(dev, notify_only);
1057	spin_unlock_irqrestore(&dmap->lock,flags);
1058}
1059EXPORT_SYMBOL(DMAbuf_outputintr);
1060
1061/* called with dmap->lock held in irq context */
1062static void do_inputintr(int dev)
1063{
1064	struct audio_operations *adev = audio_devs[dev];
1065	struct dma_buffparms *dmap = adev->dmap_in;
1066
1067	if (dmap->raw_buf == NULL) {
1068		printk(KERN_ERR "Sound: Fatal error. Audio interrupt after freeing buffers.\n");
1069		return;
1070	}
1071	if (dmap->mapping_flags & DMA_MAP_MAPPED) {
1072		dmap->qtail = (dmap->qtail + 1) % dmap->nbufs;
1073		if (dmap->qtail == 0) {		/* Wrapped */
1074			dmap->byte_counter += dmap->bytes_in_use;
1075			if (dmap->byte_counter >= dmap->max_byte_counter) {	/* Overflow */
1076				long decr = dmap->byte_counter;
1077				dmap->byte_counter = (dmap->byte_counter % dmap->bytes_in_use) + dmap->bytes_in_use;
1078				decr -= dmap->byte_counter;
1079				dmap->user_counter -= decr;
1080			}
1081		}
1082		dmap->qlen++;
1083
1084		if (!(adev->flags & DMA_AUTOMODE)) {
1085			if (dmap->needs_reorg)
1086				reorganize_buffers(dev, dmap, 0);
1087			local_start_dma(adev, dmap->raw_buf_phys, dmap->bytes_in_use,DMA_MODE_READ);
1088			adev->d->start_input(dev, dmap->raw_buf_phys + dmap->qtail * dmap->fragment_size,
1089					     dmap->fragment_size, 1);
1090			if (adev->d->trigger)
1091				adev->d->trigger(dev, adev->enable_bits * adev->go);
1092		}
1093		dmap->flags |= DMA_ACTIVE;
1094	} else if (dmap->qlen >= (dmap->nbufs - 1)) {
1095		printk(KERN_WARNING "Sound: Recording overrun\n");
1096		dmap->underrun_count++;
1097
1098		/* Just throw away the oldest fragment but keep the engine running */
1099		dmap->qhead = (dmap->qhead + 1) % dmap->nbufs;
1100		dmap->qtail = (dmap->qtail + 1) % dmap->nbufs;
1101	} else if (dmap->qlen >= 0 && dmap->qlen < dmap->nbufs) {
1102		dmap->qlen++;
1103		dmap->qtail = (dmap->qtail + 1) % dmap->nbufs;
1104		if (dmap->qtail == 0) {		/* Wrapped */
1105			dmap->byte_counter += dmap->bytes_in_use;
1106			if (dmap->byte_counter >= dmap->max_byte_counter) {	/* Overflow */
1107				long decr = dmap->byte_counter;
1108				dmap->byte_counter = (dmap->byte_counter % dmap->bytes_in_use) + dmap->bytes_in_use;
1109				decr -= dmap->byte_counter;
1110				dmap->user_counter -= decr;
1111			}
1112		}
1113	}
1114	if (!(adev->flags & DMA_AUTOMODE) || (dmap->flags & DMA_NODMA)) {
1115		local_start_dma(adev, dmap->raw_buf_phys, dmap->bytes_in_use, DMA_MODE_READ);
1116		adev->d->start_input(dev, dmap->raw_buf_phys + dmap->qtail * dmap->fragment_size, dmap->fragment_size, 1);
1117		if (adev->d->trigger)
1118			adev->d->trigger(dev,adev->enable_bits * adev->go);
1119	}
1120	dmap->flags |= DMA_ACTIVE;
1121	if (dmap->qlen > 0)
1122	{
1123		wake_up(&adev->in_sleeper);
1124		wake_up(&adev->poll_sleeper);
1125	}
1126}
1127/* called in irq context */
1128void DMAbuf_inputintr(int dev)
1129{
1130	struct audio_operations *adev = audio_devs[dev];
1131	struct dma_buffparms *dmap = adev->dmap_in;
1132	unsigned long flags;
1133
1134	spin_lock_irqsave(&dmap->lock,flags);
1135
1136	if (!(dmap->flags & DMA_NODMA)) {
1137		int chan = dmap->dma, pos, n;
1138		unsigned long f;
1139
1140		f=claim_dma_lock();
1141		if(!isa_dma_bridge_buggy)
1142			disable_dma(dmap->dma);
1143		clear_dma_ff(chan);
1144		pos = dmap->bytes_in_use - get_dma_residue(chan);
1145		if(!isa_dma_bridge_buggy)
1146			enable_dma(dmap->dma);
1147		release_dma_lock(f);
1148
1149		pos = pos / dmap->fragment_size;	/* Actual qhead */
1150		if (pos < 0 || pos >= dmap->nbufs)
1151			pos = 0;
1152
1153		n = 0;
1154		while (dmap->qtail != pos && ++n < dmap->nbufs)
1155			do_inputintr(dev);
1156	} else
1157		do_inputintr(dev);
1158	spin_unlock_irqrestore(&dmap->lock,flags);
1159}
1160EXPORT_SYMBOL(DMAbuf_inputintr);
1161
1162void DMAbuf_init(int dev, int dma1, int dma2)
1163{
1164	struct audio_operations *adev = audio_devs[dev];
1165	/*
1166	 * NOTE! This routine could be called several times.
1167	 */
1168
1169	if (adev && adev->dmap_out == NULL) {
1170		if (adev->d == NULL)
1171			panic("OSS: audio_devs[%d]->d == NULL\n", dev);
1172
1173		if (adev->parent_dev) {	 /* Use DMA map of the parent dev */
1174			int parent = adev->parent_dev - 1;
1175			adev->dmap_out = audio_devs[parent]->dmap_out;
1176			adev->dmap_in = audio_devs[parent]->dmap_in;
1177		} else {
1178			adev->dmap_out = adev->dmap_in = &adev->dmaps[0];
1179			adev->dmap_out->dma = dma1;
1180			if (adev->flags & DMA_DUPLEX) {
1181				adev->dmap_in = &adev->dmaps[1];
1182				adev->dmap_in->dma = dma2;
1183			}
1184		}
1185		/* Persistent DMA buffers allocated here */
1186		if (sound_dmap_flag == DMAP_KEEP_ON_CLOSE) {
1187			if (adev->dmap_in->raw_buf == NULL)
1188				sound_alloc_dmap(adev->dmap_in);
1189			if (adev->dmap_out->raw_buf == NULL)
1190				sound_alloc_dmap(adev->dmap_out);
1191		}
1192	}
1193}
1194
1195/* No kernel lock - DMAbuf_activate_recording protected by global cli/sti */
1196static unsigned int poll_input(struct file * file, int dev, poll_table *wait)
1197{
1198	struct audio_operations *adev = audio_devs[dev];
1199	struct dma_buffparms *dmap = adev->dmap_in;
1200
1201	if (!(adev->open_mode & OPEN_READ))
1202		return 0;
1203	if (dmap->mapping_flags & DMA_MAP_MAPPED) {
1204		if (dmap->qlen)
1205			return POLLIN | POLLRDNORM;
1206		return 0;
1207	}
1208	if (dmap->dma_mode != DMODE_INPUT) {
1209		if (dmap->dma_mode == DMODE_NONE &&
1210		    adev->enable_bits & PCM_ENABLE_INPUT &&
1211		    !dmap->qlen && adev->go) {
1212			unsigned long flags;
1213
1214			spin_lock_irqsave(&dmap->lock,flags);
1215			DMAbuf_activate_recording(dev, dmap);
1216			spin_unlock_irqrestore(&dmap->lock,flags);
1217		}
1218		return 0;
1219	}
1220	if (!dmap->qlen)
1221		return 0;
1222	return POLLIN | POLLRDNORM;
1223}
1224
1225static unsigned int poll_output(struct file * file, int dev, poll_table *wait)
1226{
1227	struct audio_operations *adev = audio_devs[dev];
1228	struct dma_buffparms *dmap = adev->dmap_out;
1229
1230	if (!(adev->open_mode & OPEN_WRITE))
1231		return 0;
1232	if (dmap->mapping_flags & DMA_MAP_MAPPED) {
1233		if (dmap->qlen)
1234			return POLLOUT | POLLWRNORM;
1235		return 0;
1236	}
1237	if (dmap->dma_mode == DMODE_INPUT)
1238		return 0;
1239	if (dmap->dma_mode == DMODE_NONE)
1240		return POLLOUT | POLLWRNORM;
1241	if (!DMAbuf_space_in_queue(dev))
1242		return 0;
1243	return POLLOUT | POLLWRNORM;
1244}
1245
1246unsigned int DMAbuf_poll(struct file * file, int dev, poll_table *wait)
1247{
1248	struct audio_operations *adev = audio_devs[dev];
1249	poll_wait(file, &adev->poll_sleeper, wait);
1250	return poll_input(file, dev, wait) | poll_output(file, dev, wait);
1251}
1252
1253void DMAbuf_deinit(int dev)
1254{
1255	struct audio_operations *adev = audio_devs[dev];
1256	/* This routine is called when driver is being unloaded */
1257	if (!adev)
1258		return;
1259
1260	/* Persistent DMA buffers deallocated here */
1261	if (sound_dmap_flag == DMAP_KEEP_ON_CLOSE) {
1262		sound_free_dmap(adev->dmap_out);
1263		if (adev->flags & DMA_DUPLEX)
1264			sound_free_dmap(adev->dmap_in);
1265	}
1266}
1267