sound/pci/mixart/mixart_core.c - linux - Git at Google

 /*
  * 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 <linux/mutex.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(struct mixart_mgr *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(struct mixart_mgr *mgr, struct mixart_msg *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( struct mixart_mgr *mgr,
 		     struct mixart_msg *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(struct mixart_mgr *mgr, struct mixart_msg *request, int max_resp_size, void *resp_data)
 {
 	struct mixart_msg 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;

 	mutex_lock(&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);
 		mutex_unlock(&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 */
 		mutex_unlock(&mgr->msg_mutex);
 		snd_printk(KERN_ERR "error: no reponse on msg %x\n", msg_frame);
 		return -EIO;
 	}

 	/* retrieve the answer into the same struct mixart_msg */
 	resp.message_id = 0;
 	resp.uid = (struct mixart_uid){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");

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


 int snd_mixart_send_msg_wait_notif(struct mixart_mgr *mgr,
 				   struct mixart_msg *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);

 	mutex_lock(&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);
 		mutex_unlock(&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 */
 		mutex_unlock(&mgr->msg_mutex);
 		snd_printk(KERN_ERR "error: notification %x not received\n", notif_event);
 		return -EIO;
 	}

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


 int snd_mixart_send_msg_nonblock(struct mixart_mgr *mgr, struct mixart_msg *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_struct mixart_msgasklet()  */
 	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)
 {
 	struct mixart_mgr *mgr = ( struct mixart_mgr*)(arg);
 	struct mixart_msg 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 mixart_mgr *mgr = dev_id;
 	int err;
 	struct mixart_msg 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;
 				struct mixart_timer_notify *notify;
 				notify = (struct mixart_timer_notify *)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 */

 					struct snd_mixart *chip  = mgr->chip[chip_number];
 					struct mixart_stream *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)) {
 						struct snd_pcm_runtime *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(struct mixart_mgr *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(struct mixart_mgr *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(struct mixart_mgr *mgr)
 {
 	/* reset miXart */
 	writel_be( 1, MIXART_REG(mgr, MIXART_BA1_BRUTAL_RESET_OFFSET) );
 	return;
 }
	/*
	* 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 <linux/mutex.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(struct mixart_mgr 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(struct mixart_mgr mgr, struct mixart_msg 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( struct mixart_mgr *mgr,
	struct mixart_msg *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(struct mixart_mgr mgr, struct mixart_msg request, int max_resp_size, void *resp_data)
	{
	struct mixart_msg 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;

	mutex_lock(&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);
	mutex_unlock(&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 */
	mutex_unlock(&mgr->msg_mutex);
	snd_printk(KERN_ERR "error: no reponse on msg %x\n", msg_frame);
	return -EIO;
	}

	/* retrieve the answer into the same struct mixart_msg */
	resp.message_id = 0;
	resp.uid = (struct mixart_uid){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");

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


	int snd_mixart_send_msg_wait_notif(struct mixart_mgr *mgr,
	struct mixart_msg *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);

	mutex_lock(&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);
	mutex_unlock(&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 */
	mutex_unlock(&mgr->msg_mutex);
	snd_printk(KERN_ERR "error: notification %x not received\n", notif_event);
	return -EIO;
	}

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


	int snd_mixart_send_msg_nonblock(struct mixart_mgr mgr, struct mixart_msg 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_struct mixart_msgasklet() */
	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)
	{
	struct mixart_mgr mgr = ( struct mixart_mgr)(arg);
	struct mixart_msg 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 mixart_mgr *mgr = dev_id;
	int err;
	struct mixart_msg 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;
	struct mixart_timer_notify *notify;
	notify = (struct mixart_timer_notify *)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 */

	struct snd_mixart *chip = mgr->chip[chip_number];
	struct mixart_stream *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)) {
	struct snd_pcm_runtime *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(struct mixart_mgr *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(struct mixart_mgr *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(struct mixart_mgr *mgr)
	{
	/* reset miXart */
	writel_be( 1, MIXART_REG(mgr, MIXART_BA1_BRUTAL_RESET_OFFSET) );
	return;
	}