xref: /openbmc/linux/sound/pci/mixart/mixart_core.c (revision a1e58bbd)
1 /*
2  * Driver for Digigram miXart soundcards
3  *
4  * low level interface with interrupt handling and mail box implementation
5  *
6  * Copyright (c) 2003 by Digigram <alsa@digigram.com>
7  *
8  *   This program is free software; you can redistribute it and/or modify
9  *   it under the terms of the GNU General Public License as published by
10  *   the Free Software Foundation; either version 2 of the License, or
11  *   (at your option) any later version.
12  *
13  *   This program is distributed in the hope that it will be useful,
14  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
15  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  *   GNU General Public License for more details.
17  *
18  *   You should have received a copy of the GNU General Public License
19  *   along with this program; if not, write to the Free Software
20  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
21  */
22 
23 #include <linux/interrupt.h>
24 #include <linux/mutex.h>
25 
26 #include <asm/io.h>
27 #include <sound/core.h>
28 #include "mixart.h"
29 #include "mixart_hwdep.h"
30 #include "mixart_core.h"
31 
32 
33 #define MSG_TIMEOUT_JIFFIES         (400 * HZ) / 1000 /* 400 ms */
34 
35 #define MSG_DESCRIPTOR_SIZE         0x24
36 #define MSG_HEADER_SIZE             (MSG_DESCRIPTOR_SIZE + 4)
37 
38 #define MSG_DEFAULT_SIZE            512
39 
40 #define MSG_TYPE_MASK               0x00000003    /* mask for following types */
41 #define MSG_TYPE_NOTIFY             0             /* embedded -> driver (only notification, do not get_msg() !) */
42 #define MSG_TYPE_COMMAND            1             /* driver <-> embedded (a command has no answer) */
43 #define MSG_TYPE_REQUEST            2             /* driver -> embedded (request will get an answer back) */
44 #define MSG_TYPE_ANSWER             3             /* embedded -> driver */
45 #define MSG_CANCEL_NOTIFY_MASK      0x80000000    /* this bit is set for a notification that has been canceled */
46 
47 
48 static int retrieve_msg_frame(struct mixart_mgr *mgr, u32 *msg_frame)
49 {
50 	/* read the message frame fifo */
51 	u32 headptr, tailptr;
52 
53 	tailptr = readl_be(MIXART_MEM(mgr, MSG_OUTBOUND_POST_TAIL));
54 	headptr = readl_be(MIXART_MEM(mgr, MSG_OUTBOUND_POST_HEAD));
55 
56 	if (tailptr == headptr)
57 		return 0; /* no message posted */
58 
59 	snd_assert( tailptr >= MSG_OUTBOUND_POST_STACK, return 0); /* error */
60 	snd_assert( tailptr < (MSG_OUTBOUND_POST_STACK+MSG_BOUND_STACK_SIZE), return 0); /* error */
61 
62 	*msg_frame = readl_be(MIXART_MEM(mgr, tailptr));
63 
64 	/* increment the tail index */
65 	tailptr += 4;
66 	if( tailptr >= (MSG_OUTBOUND_POST_STACK+MSG_BOUND_STACK_SIZE) )
67 		tailptr = MSG_OUTBOUND_POST_STACK;
68 	writel_be(tailptr, MIXART_MEM(mgr, MSG_OUTBOUND_POST_TAIL));
69 
70 	return 1;
71 }
72 
73 static int get_msg(struct mixart_mgr *mgr, struct mixart_msg *resp,
74 		   u32 msg_frame_address )
75 {
76 	unsigned long flags;
77 	u32  headptr;
78 	u32  size;
79 	int  err;
80 #ifndef __BIG_ENDIAN
81 	unsigned int i;
82 #endif
83 
84 	spin_lock_irqsave(&mgr->msg_lock, flags);
85 	err = 0;
86 
87 	/* copy message descriptor from miXart to driver */
88 	size                =  readl_be(MIXART_MEM(mgr, msg_frame_address));       /* size of descriptor + response */
89 	resp->message_id    =  readl_be(MIXART_MEM(mgr, msg_frame_address + 4));   /* dwMessageID */
90 	resp->uid.object_id =  readl_be(MIXART_MEM(mgr, msg_frame_address + 8));   /* uidDest */
91 	resp->uid.desc      =  readl_be(MIXART_MEM(mgr, msg_frame_address + 12));  /* */
92 
93 	if( (size < MSG_DESCRIPTOR_SIZE) || (resp->size < (size - MSG_DESCRIPTOR_SIZE))) {
94 		err = -EINVAL;
95 		snd_printk(KERN_ERR "problem with response size = %d\n", size);
96 		goto _clean_exit;
97 	}
98 	size -= MSG_DESCRIPTOR_SIZE;
99 
100 	memcpy_fromio(resp->data, MIXART_MEM(mgr, msg_frame_address + MSG_HEADER_SIZE ), size);
101 	resp->size = size;
102 
103 	/* swap if necessary */
104 #ifndef __BIG_ENDIAN
105 	size /= 4; /* u32 size */
106 	for(i=0; i < size; i++) {
107 		((u32*)resp->data)[i] = be32_to_cpu(((u32*)resp->data)[i]);
108 	}
109 #endif
110 
111 	/*
112 	 * free message frame address
113 	 */
114 	headptr = readl_be(MIXART_MEM(mgr, MSG_OUTBOUND_FREE_HEAD));
115 
116 	if( (headptr < MSG_OUTBOUND_FREE_STACK) || ( headptr >= (MSG_OUTBOUND_FREE_STACK+MSG_BOUND_STACK_SIZE))) {
117 		err = -EINVAL;
118 		goto _clean_exit;
119 	}
120 
121 	/* give address back to outbound fifo */
122 	writel_be(msg_frame_address, MIXART_MEM(mgr, headptr));
123 
124 	/* increment the outbound free head */
125 	headptr += 4;
126 	if( headptr >= (MSG_OUTBOUND_FREE_STACK+MSG_BOUND_STACK_SIZE) )
127 		headptr = MSG_OUTBOUND_FREE_STACK;
128 
129 	writel_be(headptr, MIXART_MEM(mgr, MSG_OUTBOUND_FREE_HEAD));
130 
131  _clean_exit:
132 	spin_unlock_irqrestore(&mgr->msg_lock, flags);
133 
134 	return err;
135 }
136 
137 
138 /*
139  * send a message to miXart. return: the msg_frame used for this message
140  */
141 /* call with mgr->msg_lock held! */
142 static int send_msg( struct mixart_mgr *mgr,
143 		     struct mixart_msg *msg,
144 		     int max_answersize,
145 		     int mark_pending,
146 		     u32 *msg_event)
147 {
148 	u32 headptr, tailptr;
149 	u32 msg_frame_address;
150 	int err, i;
151 
152 	snd_assert(msg->size % 4 == 0, return -EINVAL);
153 
154 	err = 0;
155 
156 	/* get message frame address */
157 	tailptr = readl_be(MIXART_MEM(mgr, MSG_INBOUND_FREE_TAIL));
158 	headptr = readl_be(MIXART_MEM(mgr, MSG_INBOUND_FREE_HEAD));
159 
160 	if (tailptr == headptr) {
161 		snd_printk(KERN_ERR "error: no message frame available\n");
162 		return -EBUSY;
163 	}
164 
165 	if( (tailptr < MSG_INBOUND_FREE_STACK) || (tailptr >= (MSG_INBOUND_FREE_STACK+MSG_BOUND_STACK_SIZE))) {
166 		return -EINVAL;
167 	}
168 
169 	msg_frame_address = readl_be(MIXART_MEM(mgr, tailptr));
170 	writel(0, MIXART_MEM(mgr, tailptr)); /* set address to zero on this fifo position */
171 
172 	/* increment the inbound free tail */
173 	tailptr += 4;
174 	if( tailptr >= (MSG_INBOUND_FREE_STACK+MSG_BOUND_STACK_SIZE) )
175 		tailptr = MSG_INBOUND_FREE_STACK;
176 
177 	writel_be(tailptr, MIXART_MEM(mgr, MSG_INBOUND_FREE_TAIL));
178 
179 	/* TODO : use memcpy_toio() with intermediate buffer to copy the message */
180 
181 	/* copy message descriptor to card memory */
182 	writel_be( msg->size + MSG_DESCRIPTOR_SIZE,      MIXART_MEM(mgr, msg_frame_address) );      /* size of descriptor + request */
183 	writel_be( msg->message_id ,                     MIXART_MEM(mgr, msg_frame_address + 4) );  /* dwMessageID */
184 	writel_be( msg->uid.object_id,                   MIXART_MEM(mgr, msg_frame_address + 8) );  /* uidDest */
185 	writel_be( msg->uid.desc,                        MIXART_MEM(mgr, msg_frame_address + 12) ); /* */
186 	writel_be( MSG_DESCRIPTOR_SIZE,                  MIXART_MEM(mgr, msg_frame_address + 16) ); /* SizeHeader */
187 	writel_be( MSG_DESCRIPTOR_SIZE,                  MIXART_MEM(mgr, msg_frame_address + 20) ); /* OffsetDLL_T16 */
188 	writel_be( msg->size,                            MIXART_MEM(mgr, msg_frame_address + 24) ); /* SizeDLL_T16 */
189 	writel_be( MSG_DESCRIPTOR_SIZE,                  MIXART_MEM(mgr, msg_frame_address + 28) ); /* OffsetDLL_DRV */
190 	writel_be( 0,                                    MIXART_MEM(mgr, msg_frame_address + 32) ); /* SizeDLL_DRV */
191 	writel_be( MSG_DESCRIPTOR_SIZE + max_answersize, MIXART_MEM(mgr, msg_frame_address + 36) ); /* dwExpectedAnswerSize */
192 
193 	/* copy message data to card memory */
194 	for( i=0; i < msg->size; i+=4 ) {
195 		writel_be( *(u32*)(msg->data + i), MIXART_MEM(mgr, MSG_HEADER_SIZE + msg_frame_address + i)  );
196 	}
197 
198 	if( mark_pending ) {
199 		if( *msg_event ) {
200 			/* the pending event is the notification we wait for ! */
201 			mgr->pending_event = *msg_event;
202 		}
203 		else {
204 			/* the pending event is the answer we wait for (same address than the request)! */
205 			mgr->pending_event = msg_frame_address;
206 
207 			/* copy address back to caller */
208 			*msg_event = msg_frame_address;
209 		}
210 	}
211 
212 	/* mark the frame as a request (will have an answer) */
213 	msg_frame_address |= MSG_TYPE_REQUEST;
214 
215 	/* post the frame */
216 	headptr = readl_be(MIXART_MEM(mgr, MSG_INBOUND_POST_HEAD));
217 
218 	if( (headptr < MSG_INBOUND_POST_STACK) || (headptr >= (MSG_INBOUND_POST_STACK+MSG_BOUND_STACK_SIZE))) {
219 		return -EINVAL;
220 	}
221 
222 	writel_be(msg_frame_address, MIXART_MEM(mgr, headptr));
223 
224 	/* increment the inbound post head */
225 	headptr += 4;
226 	if( headptr >= (MSG_INBOUND_POST_STACK+MSG_BOUND_STACK_SIZE) )
227 		headptr = MSG_INBOUND_POST_STACK;
228 
229 	writel_be(headptr, MIXART_MEM(mgr, MSG_INBOUND_POST_HEAD));
230 
231 	return 0;
232 }
233 
234 
235 int snd_mixart_send_msg(struct mixart_mgr *mgr, struct mixart_msg *request, int max_resp_size, void *resp_data)
236 {
237 	struct mixart_msg resp;
238 	u32 msg_frame = 0; /* set to 0, so it's no notification to wait for, but the answer */
239 	int err;
240 	wait_queue_t wait;
241 	long timeout;
242 
243 	mutex_lock(&mgr->msg_mutex);
244 
245 	init_waitqueue_entry(&wait, current);
246 
247 	spin_lock_irq(&mgr->msg_lock);
248 	/* send the message */
249 	err = send_msg(mgr, request, max_resp_size, 1, &msg_frame);  /* send and mark the answer pending */
250 	if (err) {
251 		spin_unlock_irq(&mgr->msg_lock);
252 		mutex_unlock(&mgr->msg_mutex);
253 		return err;
254 	}
255 
256 	set_current_state(TASK_UNINTERRUPTIBLE);
257 	add_wait_queue(&mgr->msg_sleep, &wait);
258 	spin_unlock_irq(&mgr->msg_lock);
259 	timeout = schedule_timeout(MSG_TIMEOUT_JIFFIES);
260 	remove_wait_queue(&mgr->msg_sleep, &wait);
261 
262 	if (! timeout) {
263 		/* error - no ack */
264 		mutex_unlock(&mgr->msg_mutex);
265 		snd_printk(KERN_ERR "error: no reponse on msg %x\n", msg_frame);
266 		return -EIO;
267 	}
268 
269 	/* retrieve the answer into the same struct mixart_msg */
270 	resp.message_id = 0;
271 	resp.uid = (struct mixart_uid){0,0};
272 	resp.data = resp_data;
273 	resp.size = max_resp_size;
274 
275 	err = get_msg(mgr, &resp, msg_frame);
276 
277 	if( request->message_id != resp.message_id )
278 		snd_printk(KERN_ERR "REPONSE ERROR!\n");
279 
280 	mutex_unlock(&mgr->msg_mutex);
281 	return err;
282 }
283 
284 
285 int snd_mixart_send_msg_wait_notif(struct mixart_mgr *mgr,
286 				   struct mixart_msg *request, u32 notif_event)
287 {
288 	int err;
289 	wait_queue_t wait;
290 	long timeout;
291 
292 	snd_assert(notif_event != 0, return -EINVAL);
293 	snd_assert((notif_event & MSG_TYPE_MASK) == MSG_TYPE_NOTIFY, return -EINVAL);
294 	snd_assert((notif_event & MSG_CANCEL_NOTIFY_MASK) == 0, return -EINVAL);
295 
296 	mutex_lock(&mgr->msg_mutex);
297 
298 	init_waitqueue_entry(&wait, current);
299 
300 	spin_lock_irq(&mgr->msg_lock);
301 	/* send the message */
302 	err = send_msg(mgr, request, MSG_DEFAULT_SIZE, 1, &notif_event);  /* send and mark the notification event pending */
303 	if(err) {
304 		spin_unlock_irq(&mgr->msg_lock);
305 		mutex_unlock(&mgr->msg_mutex);
306 		return err;
307 	}
308 
309 	set_current_state(TASK_UNINTERRUPTIBLE);
310 	add_wait_queue(&mgr->msg_sleep, &wait);
311 	spin_unlock_irq(&mgr->msg_lock);
312 	timeout = schedule_timeout(MSG_TIMEOUT_JIFFIES);
313 	remove_wait_queue(&mgr->msg_sleep, &wait);
314 
315 	if (! timeout) {
316 		/* error - no ack */
317 		mutex_unlock(&mgr->msg_mutex);
318 		snd_printk(KERN_ERR "error: notification %x not received\n", notif_event);
319 		return -EIO;
320 	}
321 
322 	mutex_unlock(&mgr->msg_mutex);
323 	return 0;
324 }
325 
326 
327 int snd_mixart_send_msg_nonblock(struct mixart_mgr *mgr, struct mixart_msg *request)
328 {
329 	u32 message_frame;
330 	unsigned long flags;
331 	int err;
332 
333 	/* just send the message (do not mark it as a pending one) */
334 	spin_lock_irqsave(&mgr->msg_lock, flags);
335 	err = send_msg(mgr, request, MSG_DEFAULT_SIZE, 0, &message_frame);
336 	spin_unlock_irqrestore(&mgr->msg_lock, flags);
337 
338 	/* the answer will be handled by snd_struct mixart_msgasklet()  */
339 	atomic_inc(&mgr->msg_processed);
340 
341 	return err;
342 }
343 
344 
345 /* common buffer of tasklet and interrupt to send/receive messages */
346 static u32 mixart_msg_data[MSG_DEFAULT_SIZE / 4];
347 
348 
349 void snd_mixart_msg_tasklet(unsigned long arg)
350 {
351 	struct mixart_mgr *mgr = ( struct mixart_mgr*)(arg);
352 	struct mixart_msg resp;
353 	u32 msg, addr, type;
354 	int err;
355 
356 	spin_lock(&mgr->lock);
357 
358 	while (mgr->msg_fifo_readptr != mgr->msg_fifo_writeptr) {
359 		msg = mgr->msg_fifo[mgr->msg_fifo_readptr];
360 		mgr->msg_fifo_readptr++;
361 		mgr->msg_fifo_readptr %= MSG_FIFO_SIZE;
362 
363 		/* process the message ... */
364 		addr = msg & ~MSG_TYPE_MASK;
365 		type = msg & MSG_TYPE_MASK;
366 
367 		switch (type) {
368 		case MSG_TYPE_ANSWER:
369 			/* answer to a message on that we did not wait for (send_msg_nonblock) */
370 			resp.message_id = 0;
371 			resp.data = mixart_msg_data;
372 			resp.size = sizeof(mixart_msg_data);
373 			err = get_msg(mgr, &resp, addr);
374 			if( err < 0 ) {
375 				snd_printk(KERN_ERR "tasklet: error(%d) reading mf %x\n", err, msg);
376 				break;
377 			}
378 
379 			switch(resp.message_id) {
380 			case MSG_STREAM_START_INPUT_STAGE_PACKET:
381 			case MSG_STREAM_START_OUTPUT_STAGE_PACKET:
382 			case MSG_STREAM_STOP_INPUT_STAGE_PACKET:
383 			case MSG_STREAM_STOP_OUTPUT_STAGE_PACKET:
384 				if(mixart_msg_data[0])
385 					snd_printk(KERN_ERR "tasklet : error MSG_STREAM_ST***_***PUT_STAGE_PACKET status=%x\n", mixart_msg_data[0]);
386 				break;
387 			default:
388 				snd_printdd("tasklet received mf(%x) : msg_id(%x) uid(%x, %x) size(%zd)\n",
389 					   msg, resp.message_id, resp.uid.object_id, resp.uid.desc, resp.size);
390 				break;
391 			}
392 			break;
393  		case MSG_TYPE_NOTIFY:
394 			/* msg contains no address ! do not get_msg() ! */
395 		case MSG_TYPE_COMMAND:
396 			/* get_msg() necessary */
397 		default:
398 			snd_printk(KERN_ERR "tasklet doesn't know what to do with message %x\n", msg);
399 		} /* switch type */
400 
401 		/* decrement counter */
402 		atomic_dec(&mgr->msg_processed);
403 
404 	} /* while there is a msg in fifo */
405 
406 	spin_unlock(&mgr->lock);
407 }
408 
409 
410 irqreturn_t snd_mixart_interrupt(int irq, void *dev_id)
411 {
412 	struct mixart_mgr *mgr = dev_id;
413 	int err;
414 	struct mixart_msg resp;
415 
416 	u32 msg;
417 	u32 it_reg;
418 
419 	spin_lock(&mgr->lock);
420 
421 	it_reg = readl_le(MIXART_REG(mgr, MIXART_PCI_OMISR_OFFSET));
422 	if( !(it_reg & MIXART_OIDI) ) {
423 		/* this device did not cause the interrupt */
424 		spin_unlock(&mgr->lock);
425 		return IRQ_NONE;
426 	}
427 
428 	/* mask all interrupts */
429 	writel_le(MIXART_HOST_ALL_INTERRUPT_MASKED, MIXART_REG(mgr, MIXART_PCI_OMIMR_OFFSET));
430 
431 	/* outdoorbell register clear */
432 	it_reg = readl(MIXART_REG(mgr, MIXART_PCI_ODBR_OFFSET));
433 	writel(it_reg, MIXART_REG(mgr, MIXART_PCI_ODBR_OFFSET));
434 
435 	/* clear interrupt */
436 	writel_le( MIXART_OIDI, MIXART_REG(mgr, MIXART_PCI_OMISR_OFFSET) );
437 
438 	/* process interrupt */
439 	while (retrieve_msg_frame(mgr, &msg)) {
440 
441 		switch (msg & MSG_TYPE_MASK) {
442 		case MSG_TYPE_COMMAND:
443 			resp.message_id = 0;
444 			resp.data = mixart_msg_data;
445 			resp.size = sizeof(mixart_msg_data);
446 			err = get_msg(mgr, &resp, msg & ~MSG_TYPE_MASK);
447 			if( err < 0 ) {
448 				snd_printk(KERN_ERR "interrupt: error(%d) reading mf %x\n", err, msg);
449 				break;
450 			}
451 
452 			if(resp.message_id == MSG_SERVICES_TIMER_NOTIFY) {
453 				int i;
454 				struct mixart_timer_notify *notify;
455 				notify = (struct mixart_timer_notify *)mixart_msg_data;
456 
457 				for(i=0; i<notify->stream_count; i++) {
458 
459 					u32 buffer_id = notify->streams[i].buffer_id;
460 					unsigned int chip_number =  (buffer_id & MIXART_NOTIFY_CARD_MASK) >> MIXART_NOTIFY_CARD_OFFSET; /* card0 to 3 */
461 					unsigned int pcm_number  =  (buffer_id & MIXART_NOTIFY_PCM_MASK ) >> MIXART_NOTIFY_PCM_OFFSET;  /* pcm0 to 3  */
462 					unsigned int sub_number  =   buffer_id & MIXART_NOTIFY_SUBS_MASK;             /* 0 to MIXART_PLAYBACK_STREAMS */
463 					unsigned int is_capture  = ((buffer_id & MIXART_NOTIFY_CAPT_MASK) != 0);      /* playback == 0 / capture == 1 */
464 
465 					struct snd_mixart *chip  = mgr->chip[chip_number];
466 					struct mixart_stream *stream;
467 
468 					if ((chip_number >= mgr->num_cards) || (pcm_number >= MIXART_PCM_TOTAL) || (sub_number >= MIXART_PLAYBACK_STREAMS)) {
469 						snd_printk(KERN_ERR "error MSG_SERVICES_TIMER_NOTIFY buffer_id (%x) pos(%d)\n",
470 							   buffer_id, notify->streams[i].sample_pos_low_part);
471 						break;
472 					}
473 
474 					if (is_capture)
475 						stream = &chip->capture_stream[pcm_number];
476 					else
477 						stream = &chip->playback_stream[pcm_number][sub_number];
478 
479 					if (stream->substream && (stream->status == MIXART_STREAM_STATUS_RUNNING)) {
480 						struct snd_pcm_runtime *runtime = stream->substream->runtime;
481 						int elapsed = 0;
482 						u64 sample_count = ((u64)notify->streams[i].sample_pos_high_part) << 32;
483 						sample_count |= notify->streams[i].sample_pos_low_part;
484 
485 						while (1) {
486 							u64 new_elapse_pos = stream->abs_period_elapsed +  runtime->period_size;
487 
488 							if (new_elapse_pos > sample_count) {
489 								break; /* while */
490 							}
491 							else {
492 								elapsed = 1;
493 								stream->buf_periods++;
494 								if (stream->buf_periods >= runtime->periods)
495 									stream->buf_periods = 0;
496 
497 								stream->abs_period_elapsed = new_elapse_pos;
498 							}
499 						}
500 						stream->buf_period_frag = (u32)( sample_count - stream->abs_period_elapsed );
501 
502 						if(elapsed) {
503 							spin_unlock(&mgr->lock);
504 							snd_pcm_period_elapsed(stream->substream);
505 							spin_lock(&mgr->lock);
506 						}
507 					}
508 				}
509 				break;
510 			}
511 			if(resp.message_id == MSG_SERVICES_REPORT_TRACES) {
512 				if(resp.size > 1) {
513 #ifndef __BIG_ENDIAN
514 					/* Traces are text: the swapped msg_data has to be swapped back ! */
515 					int i;
516 					for(i=0; i<(resp.size/4); i++) {
517 						(mixart_msg_data)[i] = cpu_to_be32((mixart_msg_data)[i]);
518 					}
519 #endif
520 					((char*)mixart_msg_data)[resp.size - 1] = 0;
521 					snd_printdd("MIXART TRACE : %s\n", (char*)mixart_msg_data);
522 				}
523 				break;
524 			}
525 
526 			snd_printdd("command %x not handled\n", resp.message_id);
527 			break;
528 
529 		case MSG_TYPE_NOTIFY:
530 			if(msg & MSG_CANCEL_NOTIFY_MASK) {
531 				msg &= ~MSG_CANCEL_NOTIFY_MASK;
532 				snd_printk(KERN_ERR "canceled notification %x !\n", msg);
533 			}
534 			/* no break, continue ! */
535 		case MSG_TYPE_ANSWER:
536 			/* answer or notification to a message we are waiting for*/
537 			spin_lock(&mgr->msg_lock);
538 			if( (msg & ~MSG_TYPE_MASK) == mgr->pending_event ) {
539 				wake_up(&mgr->msg_sleep);
540 				mgr->pending_event = 0;
541 			}
542 			/* answer to a message we did't want to wait for */
543 			else {
544 				mgr->msg_fifo[mgr->msg_fifo_writeptr] = msg;
545 				mgr->msg_fifo_writeptr++;
546 				mgr->msg_fifo_writeptr %= MSG_FIFO_SIZE;
547 				tasklet_hi_schedule(&mgr->msg_taskq);
548 			}
549 			spin_unlock(&mgr->msg_lock);
550 			break;
551 		case MSG_TYPE_REQUEST:
552 		default:
553 			snd_printdd("interrupt received request %x\n", msg);
554 			/* TODO : are there things to do here ? */
555 			break;
556 		} /* switch on msg type */
557 	} /* while there are msgs */
558 
559 	/* allow interrupt again */
560 	writel_le( MIXART_ALLOW_OUTBOUND_DOORBELL, MIXART_REG( mgr, MIXART_PCI_OMIMR_OFFSET));
561 
562 	spin_unlock(&mgr->lock);
563 
564 	return IRQ_HANDLED;
565 }
566 
567 
568 void snd_mixart_init_mailbox(struct mixart_mgr *mgr)
569 {
570 	writel( 0, MIXART_MEM( mgr, MSG_HOST_RSC_PROTECTION ) );
571 	writel( 0, MIXART_MEM( mgr, MSG_AGENT_RSC_PROTECTION ) );
572 
573 	/* allow outbound messagebox to generate interrupts */
574 	if(mgr->irq >= 0) {
575 		writel_le( MIXART_ALLOW_OUTBOUND_DOORBELL, MIXART_REG( mgr, MIXART_PCI_OMIMR_OFFSET));
576 	}
577 	return;
578 }
579 
580 void snd_mixart_exit_mailbox(struct mixart_mgr *mgr)
581 {
582 	/* no more interrupts on outbound messagebox */
583 	writel_le( MIXART_HOST_ALL_INTERRUPT_MASKED, MIXART_REG( mgr, MIXART_PCI_OMIMR_OFFSET));
584 	return;
585 }
586 
587 void snd_mixart_reset_board(struct mixart_mgr *mgr)
588 {
589 	/* reset miXart */
590 	writel_be( 1, MIXART_REG(mgr, MIXART_BA1_BRUTAL_RESET_OFFSET) );
591 	return;
592 }
593