aboutsummaryrefslogtreecommitdiff
path: root/sound/pci/mixart/mixart_core.c
blob: ba0027f50944fe06ad56ed0288c984c531a06e92 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
/*
 * Driver for Digigram miXart soundcards
 *
 * low level interface with interrupt handling and mail box implementation
 *
 * Copyright (c) 2003 by Digigram <alsa@digigram.com>
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 */

#include <sound/driver.h>
#include <linux/interrupt.h>
#include <asm/io.h>
#include <sound/core.h>
#include "mixart.h"
#include "mixart_hwdep.h"
#include "mixart_core.h"


#define MSG_TIMEOUT_JIFFIES         (400 * HZ) / 1000 /* 400 ms */

#define MSG_DESCRIPTOR_SIZE         0x24
#define MSG_HEADER_SIZE             (MSG_DESCRIPTOR_SIZE + 4)

#define MSG_DEFAULT_SIZE            512

#define MSG_TYPE_MASK               0x00000003    /* mask for following types */
#define MSG_TYPE_NOTIFY             0             /* embedded -> driver (only notification, do not get_msg() !) */
#define MSG_TYPE_COMMAND            1             /* driver <-> embedded (a command has no answer) */
#define MSG_TYPE_REQUEST            2             /* driver -> embedded (request will get an answer back) */
#define MSG_TYPE_ANSWER             3             /* embedded -> driver */
#define MSG_CANCEL_NOTIFY_MASK      0x80000000    /* this bit is set for a notification that has been canceled */


static int retrieve_msg_frame(mixart_mgr_t *mgr, u32 *msg_frame)
{
	/* read the message frame fifo */
	u32 headptr, tailptr;

	tailptr = readl_be(MIXART_MEM(mgr, MSG_OUTBOUND_POST_TAIL));
	headptr = readl_be(MIXART_MEM(mgr, MSG_OUTBOUND_POST_HEAD));

	if (tailptr == headptr)
		return 0; /* no message posted */

	snd_assert( tailptr >= MSG_OUTBOUND_POST_STACK, return 0); /* error */
	snd_assert( tailptr < (MSG_OUTBOUND_POST_STACK+MSG_BOUND_STACK_SIZE), return 0); /* error */

	*msg_frame = readl_be(MIXART_MEM(mgr, tailptr));

	/* increment the tail index */
	tailptr += 4;
	if( tailptr >= (MSG_OUTBOUND_POST_STACK+MSG_BOUND_STACK_SIZE) )
		tailptr = MSG_OUTBOUND_POST_STACK;
	writel_be(tailptr, MIXART_MEM(mgr, MSG_OUTBOUND_POST_TAIL));

	return 1;
}

static int get_msg(mixart_mgr_t *mgr, mixart_msg_t *resp, u32 msg_frame_address )
{
	unsigned long flags;
	u32  headptr;
	u32  size;
	int  err;
#ifndef __BIG_ENDIAN
	unsigned int i;
#endif

	spin_lock_irqsave(&mgr->msg_lock, flags);
	err = 0;

	/* copy message descriptor from miXart to driver */
	size                =  readl_be(MIXART_MEM(mgr, msg_frame_address));       /* size of descriptor + response */
	resp->message_id    =  readl_be(MIXART_MEM(mgr, msg_frame_address + 4));   /* dwMessageID */
	resp->uid.object_id =  readl_be(MIXART_MEM(mgr, msg_frame_address + 8));   /* uidDest */
	resp->uid.desc      =  readl_be(MIXART_MEM(mgr, msg_frame_address + 12));  /* */

	if( (size < MSG_DESCRIPTOR_SIZE) || (resp->size < (size - MSG_DESCRIPTOR_SIZE))) {
		err = -EINVAL;
		snd_printk(KERN_ERR "problem with response size = %d\n", size);
		goto _clean_exit;
	}
	size -= MSG_DESCRIPTOR_SIZE;

	memcpy_fromio(resp->data, MIXART_MEM(mgr, msg_frame_address + MSG_HEADER_SIZE ), size);
	resp->size = size;

	/* swap if necessary */
#ifndef __BIG_ENDIAN
	size /= 4; /* u32 size */
	for(i=0; i < size; i++) {
		((u32*)resp->data)[i] = be32_to_cpu(((u32*)resp->data)[i]);
	}
#endif

	/*
	 * free message frame address
	 */
	headptr = readl_be(MIXART_MEM(mgr, MSG_OUTBOUND_FREE_HEAD));

	if( (headptr < MSG_OUTBOUND_FREE_STACK) || ( headptr >= (MSG_OUTBOUND_FREE_STACK+MSG_BOUND_STACK_SIZE))) {
		err = -EINVAL;
		goto _clean_exit;
	}

	/* give address back to outbound fifo */
	writel_be(msg_frame_address, MIXART_MEM(mgr, headptr));

	/* increment the outbound free head */
	headptr += 4;
	if( headptr >= (MSG_OUTBOUND_FREE_STACK+MSG_BOUND_STACK_SIZE) )
		headptr = MSG_OUTBOUND_FREE_STACK;

	writel_be(headptr, MIXART_MEM(mgr, MSG_OUTBOUND_FREE_HEAD));

 _clean_exit:
	spin_unlock_irqrestore(&mgr->msg_lock, flags);

	return err;
}


/*
 * send a message to miXart. return: the msg_frame used for this message
 */
/* call with mgr->msg_lock held! */
static int send_msg( mixart_mgr_t *mgr,
		     mixart_msg_t *msg,
		     int max_answersize,
		     int mark_pending,
		     u32 *msg_event)
{
	u32 headptr, tailptr;
	u32 msg_frame_address;
	int err, i;

	snd_assert(msg->size % 4 == 0, return -EINVAL);

	err = 0;

	/* get message frame address */
	tailptr = readl_be(MIXART_MEM(mgr, MSG_INBOUND_FREE_TAIL));
	headptr = readl_be(MIXART_MEM(mgr, MSG_INBOUND_FREE_HEAD));

	if (tailptr == headptr) {
		snd_printk(KERN_ERR "error: no message frame available\n");
		return -EBUSY;
	}

	if( (tailptr < MSG_INBOUND_FREE_STACK) || (tailptr >= (MSG_INBOUND_FREE_STACK+MSG_BOUND_STACK_SIZE))) {
		return -EINVAL;
	}

	msg_frame_address = readl_be(MIXART_MEM(mgr, tailptr));
	writel(0, MIXART_MEM(mgr, tailptr)); /* set address to zero on this fifo position */

	/* increment the inbound free tail */
	tailptr += 4;
	if( tailptr >= (MSG_INBOUND_FREE_STACK+MSG_BOUND_STACK_SIZE) )
		tailptr = MSG_INBOUND_FREE_STACK;

	writel_be(tailptr, MIXART_MEM(mgr, MSG_INBOUND_FREE_TAIL));

	/* TODO : use memcpy_toio() with intermediate buffer to copy the message */

	/* copy message descriptor to card memory */
	writel_be( msg->size + MSG_DESCRIPTOR_SIZE,      MIXART_MEM(mgr, msg_frame_address) );      /* size of descriptor + request */
	writel_be( msg->message_id ,                     MIXART_MEM(mgr, msg_frame_address + 4) );  /* dwMessageID */
	writel_be( msg->uid.object_id,                   MIXART_MEM(mgr, msg_frame_address + 8) );  /* uidDest */
	writel_be( msg->uid.desc,                        MIXART_MEM(mgr, msg_frame_address + 12) ); /* */
	writel_be( MSG_DESCRIPTOR_SIZE,                  MIXART_MEM(mgr, msg_frame_address + 16) ); /* SizeHeader */
	writel_be( MSG_DESCRIPTOR_SIZE,                  MIXART_MEM(mgr, msg_frame_address + 20) ); /* OffsetDLL_T16 */
	writel_be( msg->size,                            MIXART_MEM(mgr, msg_frame_address + 24) ); /* SizeDLL_T16 */
	writel_be( MSG_DESCRIPTOR_SIZE,                  MIXART_MEM(mgr, msg_frame_address + 28) ); /* OffsetDLL_DRV */
	writel_be( 0,                                    MIXART_MEM(mgr, msg_frame_address + 32) ); /* SizeDLL_DRV */
	writel_be( MSG_DESCRIPTOR_SIZE + max_answersize, MIXART_MEM(mgr, msg_frame_address + 36) ); /* dwExpectedAnswerSize */

	/* copy message data to card memory */
	for( i=0; i < msg->size; i+=4 ) {
		writel_be( *(u32*)(msg->data + i), MIXART_MEM(mgr, MSG_HEADER_SIZE + msg_frame_address + i)  );
	}

	if( mark_pending ) {
		if( *msg_event ) {
			/* the pending event is the notification we wait for ! */
			mgr->pending_event = *msg_event;
		}
		else {
			/* the pending event is the answer we wait for (same address than the request)! */
			mgr->pending_event = msg_frame_address;

			/* copy address back to caller */
			*msg_event = msg_frame_address;
		}
	}

	/* mark the frame as a request (will have an answer) */
	msg_frame_address |= MSG_TYPE_REQUEST;

	/* post the frame */
	headptr = readl_be(MIXART_MEM(mgr, MSG_INBOUND_POST_HEAD));

	if( (headptr < MSG_INBOUND_POST_STACK) || (headptr >= (MSG_INBOUND_POST_STACK+MSG_BOUND_STACK_SIZE))) {
		return -EINVAL;
	}

	writel_be(msg_frame_address, MIXART_MEM(mgr, headptr));

	/* increment the inbound post head */
	headptr += 4;
	if( headptr >= (MSG_INBOUND_POST_STACK+MSG_BOUND_STACK_SIZE) )
		headptr = MSG_INBOUND_POST_STACK;

	writel_be(headptr, MIXART_MEM(mgr, MSG_INBOUND_POST_HEAD));

	return 0;
}


int snd_mixart_send_msg(mixart_mgr_t *mgr, mixart_msg_t *request, int max_resp_size, void *resp_data)
{
	mixart_msg_t resp;
	u32 msg_frame = 0; /* set to 0, so it's no notification to wait for, but the answer */
	int err;
	wait_queue_t wait;
	long timeout;

	down(&mgr->msg_mutex);

	init_waitqueue_entry(&wait, current);

	spin_lock_irq(&mgr->msg_lock);
	/* send the message */
	err = send_msg(mgr, request, max_resp_size, 1, &msg_frame);  /* send and mark the answer pending */
	if (err) {
		spin_unlock_irq(&mgr->msg_lock);
		up(&mgr->msg_mutex);
		return err;
	}

	set_current_state(TASK_UNINTERRUPTIBLE);
	add_wait_queue(&mgr->msg_sleep, &wait);
	spin_unlock_irq(&mgr->msg_lock);
	timeout = schedule_timeout(MSG_TIMEOUT_JIFFIES);
	remove_wait_queue(&mgr->msg_sleep, &wait);

	if (! timeout) {
		/* error - no ack */
		up(&mgr->msg_mutex);
		snd_printk(KERN_ERR "error: no reponse on msg %x\n", msg_frame);
		return -EIO;
	}

	/* retrieve the answer into the same mixart_msg_t */
	resp.message_id = 0;
	resp.uid = (mixart_uid_t){0,0};
	resp.data = resp_data;
	resp.size = max_resp_size;

	err = get_msg(mgr, &resp, msg_frame);

	if( request->message_id != resp.message_id )
		snd_printk(KERN_ERR "REPONSE ERROR!\n");

	up(&mgr->msg_mutex);
	return err;
}


int snd_mixart_send_msg_wait_notif(mixart_mgr_t *mgr, mixart_msg_t *request, u32 notif_event)
{
	int err;
	wait_queue_t wait;
	long timeout;

	snd_assert(notif_event != 0, return -EINVAL);
	snd_assert((notif_event & MSG_TYPE_MASK) == MSG_TYPE_NOTIFY, return -EINVAL);
	snd_assert((notif_event & MSG_CANCEL_NOTIFY_MASK) == 0, return -EINVAL);

	down(&mgr->msg_mutex);

	init_waitqueue_entry(&wait, current);

	spin_lock_irq(&mgr->msg_lock);
	/* send the message */
	err = send_msg(mgr, request, MSG_DEFAULT_SIZE, 1, &notif_event);  /* send and mark the notification event pending */
	if(err) {
		spin_unlock_irq(&mgr->msg_lock);
		up(&mgr->msg_mutex);
		return err;
	}

	set_current_state(TASK_UNINTERRUPTIBLE);
	add_wait_queue(&mgr->msg_sleep, &wait);
	spin_unlock_irq(&mgr->msg_lock);
	timeout = schedule_timeout(MSG_TIMEOUT_JIFFIES);
	remove_wait_queue(&mgr->msg_sleep, &wait);

	if (! timeout) {
		/* error - no ack */
		up(&mgr->msg_mutex);
		snd_printk(KERN_ERR "error: notification %x not received\n", notif_event);
		return -EIO;
	}

	up(&mgr->msg_mutex);
	return 0;
}


int snd_mixart_send_msg_nonblock(mixart_mgr_t *mgr, mixart_msg_t *request)
{
	u32 message_frame;
	unsigned long flags;
	int err;

	/* just send the message (do not mark it as a pending one) */
	spin_lock_irqsave(&mgr->msg_lock, flags);
	err = send_msg(mgr, request, MSG_DEFAULT_SIZE, 0, &message_frame);
	spin_unlock_irqrestore(&mgr->msg_lock, flags);

	/* the answer will be handled by snd_mixart_msg_tasklet()  */
	atomic_inc(&mgr->msg_processed);

	return err;
}


/* common buffer of tasklet and interrupt to send/receive messages */
static u32 mixart_msg_data[MSG_DEFAULT_SIZE / 4];


void snd_mixart_msg_tasklet( unsigned long arg)
{
	mixart_mgr_t *mgr = ( mixart_mgr_t*)(arg);
	mixart_msg_t resp;
	u32 msg, addr, type;
	int err;

	spin_lock(&mgr->lock);

	while (mgr->msg_fifo_readptr != mgr->msg_fifo_writeptr) {
		msg = mgr->msg_fifo[mgr->msg_fifo_readptr];
		mgr->msg_fifo_readptr++;
		mgr->msg_fifo_readptr %= MSG_FIFO_SIZE;

		/* process the message ... */
		addr = msg & ~MSG_TYPE_MASK;
		type = msg & MSG_TYPE_MASK;

		switch (type) {
		case MSG_TYPE_ANSWER:
			/* answer to a message on that we did not wait for (send_msg_nonblock) */
			resp.message_id = 0;
			resp.data = mixart_msg_data;
			resp.size = sizeof(mixart_msg_data);
			err = get_msg(mgr, &resp, addr);
			if( err < 0 ) {
				snd_printk(KERN_ERR "tasklet: error(%d) reading mf %x\n", err, msg);
				break;
			}

			switch(resp.message_id) {
			case MSG_STREAM_START_INPUT_STAGE_PACKET:
			case MSG_STREAM_START_OUTPUT_STAGE_PACKET:
			case MSG_STREAM_STOP_INPUT_STAGE_PACKET:
			case MSG_STREAM_STOP_OUTPUT_STAGE_PACKET:
				if(mixart_msg_data[0])
					snd_printk(KERN_ERR "tasklet : error MSG_STREAM_ST***_***PUT_STAGE_PACKET status=%x\n", mixart_msg_data[0]);
				break;
			default:
				snd_printdd("tasklet received mf(%x) : msg_id(%x) uid(%x, %x) size(%zd)\n",
					   msg, resp.message_id, resp.uid.object_id, resp.uid.desc, resp.size);
				break;
			}
			break;
 		case MSG_TYPE_NOTIFY:
			/* msg contains no address ! do not get_msg() ! */
		case MSG_TYPE_COMMAND:
			/* get_msg() necessary */
		default:
			snd_printk(KERN_ERR "tasklet doesn't know what to do with message %x\n", msg);
		} /* switch type */

		/* decrement counter */
		atomic_dec(&mgr->msg_processed);

	} /* while there is a msg in fifo */

	spin_unlock(&mgr->lock);
}


irqreturn_t snd_mixart_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
	mixart_mgr_t *mgr = dev_id;
	int err;
	mixart_msg_t resp;

	u32 msg;
	u32 it_reg;

	spin_lock(&mgr->lock);

	it_reg = readl_le(MIXART_REG(mgr, MIXART_PCI_OMISR_OFFSET));
	if( !(it_reg & MIXART_OIDI) ) {
		/* this device did not cause the interrupt */
		spin_unlock(&mgr->lock);
		return IRQ_NONE;
	}

	/* mask all interrupts */
	writel_le(MIXART_HOST_ALL_INTERRUPT_MASKED, MIXART_REG(mgr, MIXART_PCI_OMIMR_OFFSET));

	/* outdoorbell register clear */
	it_reg = readl(MIXART_REG(mgr, MIXART_PCI_ODBR_OFFSET));
	writel(it_reg, MIXART_REG(mgr, MIXART_PCI_ODBR_OFFSET));

	/* clear interrupt */
	writel_le( MIXART_OIDI, MIXART_REG(mgr, MIXART_PCI_OMISR_OFFSET) );

	/* process interrupt */
	while (retrieve_msg_frame(mgr, &msg)) {

		switch (msg & MSG_TYPE_MASK) {
		case MSG_TYPE_COMMAND:
			resp.message_id = 0;
			resp.data = mixart_msg_data;
			resp.size = sizeof(mixart_msg_data);
			err = get_msg(mgr, &resp, msg & ~MSG_TYPE_MASK);
			if( err < 0 ) {
				snd_printk(KERN_ERR "interrupt: error(%d) reading mf %x\n", err, msg);
				break;
			}

			if(resp.message_id == MSG_SERVICES_TIMER_NOTIFY) {
				int i;
				mixart_timer_notify_t *notify = (mixart_timer_notify_t*)mixart_msg_data;

				for(i=0; i<notify->stream_count; i++) {

					u32 buffer_id = notify->streams[i].buffer_id;
					unsigned int chip_number =  (buffer_id & MIXART_NOTIFY_CARD_MASK) >> MIXART_NOTIFY_CARD_OFFSET; /* card0 to 3 */
					unsigned int pcm_number  =  (buffer_id & MIXART_NOTIFY_PCM_MASK ) >> MIXART_NOTIFY_PCM_OFFSET;  /* pcm0 to 3  */
					unsigned int sub_number  =   buffer_id & MIXART_NOTIFY_SUBS_MASK;             /* 0 to MIXART_PLAYBACK_STREAMS */
					unsigned int is_capture  = ((buffer_id & MIXART_NOTIFY_CAPT_MASK) != 0);      /* playback == 0 / capture == 1 */

					mixart_t *chip  = mgr->chip[chip_number];
					mixart_stream_t *stream;

					if ((chip_number >= mgr->num_cards) || (pcm_number >= MIXART_PCM_TOTAL) || (sub_number >= MIXART_PLAYBACK_STREAMS)) {
						snd_printk(KERN_ERR "error MSG_SERVICES_TIMER_NOTIFY buffer_id (%x) pos(%d)\n",
							   buffer_id, notify->streams[i].sample_pos_low_part);
						break;
					}

					if (is_capture)
						stream = &chip->capture_stream[pcm_number];
					else
						stream = &chip->playback_stream[pcm_number][sub_number];

					if (stream->substream && (stream->status == MIXART_STREAM_STATUS_RUNNING)) {
						snd_pcm_runtime_t *runtime = stream->substream->runtime;
						int elapsed = 0;
						u64 sample_count = ((u64)notify->streams[i].sample_pos_high_part) << 32;
						sample_count |= notify->streams[i].sample_pos_low_part;

						while (1) {
							u64 new_elapse_pos = stream->abs_period_elapsed +  runtime->period_size;

							if (new_elapse_pos > sample_count) {
								break; /* while */
							}
							else {
								elapsed = 1;
								stream->buf_periods++;
								if (stream->buf_periods >= runtime->periods)
									stream->buf_periods = 0;

								stream->abs_period_elapsed = new_elapse_pos;
							}
						}
						stream->buf_period_frag = (u32)( sample_count - stream->abs_period_elapsed );

						if(elapsed) {
							spin_unlock(&mgr->lock);
							snd_pcm_period_elapsed(stream->substream);
							spin_lock(&mgr->lock);
						}
					}
				}
				break;
			}
			if(resp.message_id == MSG_SERVICES_REPORT_TRACES) {
				if(resp.size > 1) {
#ifndef __BIG_ENDIAN
					/* Traces are text: the swapped msg_data has to be swapped back ! */
					int i;
					for(i=0; i<(resp.size/4); i++) {
						(mixart_msg_data)[i] = cpu_to_be32((mixart_msg_data)[i]);
					}
#endif
					((char*)mixart_msg_data)[resp.size - 1] = 0;
					snd_printdd("MIXART TRACE : %s\n", (char*)mixart_msg_data);
				}
				break;
			}

			snd_printdd("command %x not handled\n", resp.message_id);
			break;

		case MSG_TYPE_NOTIFY:
			if(msg & MSG_CANCEL_NOTIFY_MASK) {
				msg &= ~MSG_CANCEL_NOTIFY_MASK;
				snd_printk(KERN_ERR "canceled notification %x !\n", msg);
			}
			/* no break, continue ! */
		case MSG_TYPE_ANSWER:
			/* answer or notification to a message we are waiting for*/
			spin_lock(&mgr->msg_lock);
			if( (msg & ~MSG_TYPE_MASK) == mgr->pending_event ) {
				wake_up(&mgr->msg_sleep);
				mgr->pending_event = 0;
			}
			/* answer to a message we did't want to wait for */
			else {
				mgr->msg_fifo[mgr->msg_fifo_writeptr] = msg;
				mgr->msg_fifo_writeptr++;
				mgr->msg_fifo_writeptr %= MSG_FIFO_SIZE;
				tasklet_hi_schedule(&mgr->msg_taskq);
			}
			spin_unlock(&mgr->msg_lock);
			break;
		case MSG_TYPE_REQUEST:
		default:
			snd_printdd("interrupt received request %x\n", msg);
			/* TODO : are there things to do here ? */
			break;
		} /* switch on msg type */
	} /* while there are msgs */

	/* allow interrupt again */
	writel_le( MIXART_ALLOW_OUTBOUND_DOORBELL, MIXART_REG( mgr, MIXART_PCI_OMIMR_OFFSET));

	spin_unlock(&mgr->lock);

	return IRQ_HANDLED;
}


void snd_mixart_init_mailbox(mixart_mgr_t *mgr)
{
	writel( 0, MIXART_MEM( mgr, MSG_HOST_RSC_PROTECTION ) );
	writel( 0, MIXART_MEM( mgr, MSG_AGENT_RSC_PROTECTION ) );

	/* allow outbound messagebox to generate interrupts */
	if(mgr->irq >= 0) {
		writel_le( MIXART_ALLOW_OUTBOUND_DOORBELL, MIXART_REG( mgr, MIXART_PCI_OMIMR_OFFSET));
	}
	return;
}

void snd_mixart_exit_mailbox(mixart_mgr_t *mgr)
{
	/* no more interrupts on outbound messagebox */
	writel_le( MIXART_HOST_ALL_INTERRUPT_MASKED, MIXART_REG( mgr, MIXART_PCI_OMIMR_OFFSET));
	return;
}

void snd_mixart_reset_board(mixart_mgr_t *mgr)
{
	/* reset miXart */
	writel_be( 1, MIXART_REG(mgr, MIXART_BA1_BRUTAL_RESET_OFFSET) );
	return;
}