mixart_core.c

linux-2.6.15.6

/*
 * Driver for Digigram miXart soundcards
 *
 * low level interface with interrupt handling and mail box implementation
 *
 * Copyright (c) 2003 by Digigram <[e-mail]>
 *
 *   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);