video1394.c

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			reg_write(ohci, d->cmdPtr, 
				  virt_to_bus(&(d->ir_prg[v.buffer][0]))|0x1);
			
			/* Run IR context */
			reg_write(ohci, d->ctrlSet, 0x8000);
		}
		else {
			/* Wake up dma context if necessary */
			if (!(reg_read(ohci, d->ctrlSet) & 0x400)) {
				PRINT(KERN_INFO, ohci->id, 
				      "Waking up iso dma ctx=%d", d->ctx);
				reg_write(ohci, d->ctrlSet, 0x1000);
			}
		}
		return 0;
		
	}
	case VIDEO1394_LISTEN_WAIT_BUFFER:
	{
		struct video1394_wait v;
		struct dma_iso_ctx *d;
		int i;

		if(copy_from_user(&v, (void *)arg, sizeof(v)))
			return -EFAULT;

		i = ir_ctx_listening(video, v.channel);
		if (i<0) return -EFAULT;
		d = video->ir_context[i];

		if ((v.buffer<0) || (v.buffer>d->num_desc)) {
			PRINT(KERN_ERR, ohci->id, 
			      "buffer %d out of range",v.buffer);
			return -EFAULT;
		}

		/*
		 * I change the way it works so that it returns 
		 * the last received frame.
		 */
		spin_lock_irqsave(&d->lock, flags);
		switch(d->buffer_status[v.buffer]) {
		case VIDEO1394_BUFFER_READY:
			d->buffer_status[v.buffer]=VIDEO1394_BUFFER_FREE;
			break;
		case VIDEO1394_BUFFER_QUEUED:
#if 1
			while(d->buffer_status[v.buffer]!=
			      VIDEO1394_BUFFER_READY) {
				spin_unlock_irqrestore(&d->lock, flags);
				interruptible_sleep_on(&d->waitq);
				spin_lock_irqsave(&d->lock, flags);
				if(signal_pending(current)) {
					spin_unlock_irqrestore(&d->lock,flags);
					return -EINTR;
				}
			}
#else
			if (wait_event_interruptible(d->waitq, 
						     d->buffer_status[v.buffer]
						     == VIDEO1394_BUFFER_READY)
			    == -ERESTARTSYS)
				return -EINTR;
#endif
			d->buffer_status[v.buffer]=VIDEO1394_BUFFER_FREE;
			break;
		default:
			PRINT(KERN_ERR, ohci->id, 
			      "buffer %d is not queued",v.buffer);
			spin_unlock_irqrestore(&d->lock, flags);
			return -EFAULT;
		}

		/*
		 * Look ahead to see how many more buffers have been received
		 */
		i=0;
		while (d->buffer_status[(v.buffer+1)%d->num_desc]==
		       VIDEO1394_BUFFER_READY) {
			v.buffer=(v.buffer+1)%d->num_desc;
			i++;
		}
		spin_unlock_irqrestore(&d->lock, flags);

		v.buffer=i;
		if(copy_to_user((void *)arg, &v, sizeof(v)))
			return -EFAULT;

		return 0;
	}
	case VIDEO1394_TALK_QUEUE_BUFFER:
	{
		struct video1394_wait v;
		struct dma_iso_ctx *d;
		int i;

		if(copy_from_user(&v, (void *)arg, sizeof(v)))
			return -EFAULT;

		i = it_ctx_talking(video, v.channel);
		if (i<0) return -EFAULT;
		d = video->it_context[i];

		if ((v.buffer<0) || (v.buffer>d->num_desc)) {
			PRINT(KERN_ERR, ohci->id, 
			      "buffer %d out of range",v.buffer);
			return -EFAULT;
		}
		
		spin_lock_irqsave(&d->lock,flags);

		if (d->buffer_status[v.buffer]!=VIDEO1394_BUFFER_FREE) {
			PRINT(KERN_ERR, ohci->id, 
			      "buffer %d is already used",v.buffer);
			spin_unlock_irqrestore(&d->lock,flags);
			return -EFAULT;
		}
		
		d->buffer_status[v.buffer]=VIDEO1394_BUFFER_QUEUED;

		if (d->last_buffer>=0) {
			d->it_prg[d->last_buffer]
				[d->nb_cmd-1].end.branchAddress = 
				(virt_to_bus(&(d->it_prg[v.buffer][0].begin.control)) 
				 & 0xfffffff0) | 0x3;

			d->it_prg[d->last_buffer]
				[d->nb_cmd-1].begin.branchAddress = 
				(virt_to_bus(&(d->it_prg[v.buffer][0].begin.control)) 
				 & 0xfffffff0) | 0x3;
		}
		d->last_buffer = v.buffer;

		d->it_prg[d->last_buffer][d->nb_cmd-1].end.branchAddress = 0;

		spin_unlock_irqrestore(&d->lock,flags);

		if (!(reg_read(ohci, d->ctrlSet) & 0x8000)) 
		{
			DBGMSG(ohci->id, "Starting iso transmit DMA ctx=%d",
			       d->ctx);

			/* Tell the controller where the first program is */
			reg_write(ohci, d->cmdPtr, 
				  virt_to_bus(&(d->it_prg[v.buffer][0]))|0x3);
			
			/* Run IT context */
			reg_write(ohci, d->ctrlSet, 0x8000);
		}
		else {
			/* Wake up dma context if necessary */
			if (!(reg_read(ohci, d->ctrlSet) & 0x400)) {
				PRINT(KERN_INFO, ohci->id, 
				      "Waking up iso transmit dma ctx=%d", 
				      d->ctx);
				reg_write(ohci, d->ctrlSet, 0x1000);
			}
		}
		return 0;
		
	}
	case VIDEO1394_TALK_WAIT_BUFFER:
	{
		struct video1394_wait v;
		struct dma_iso_ctx *d;
		int i;

		if(copy_from_user(&v, (void *)arg, sizeof(v)))
			return -EFAULT;

		i = it_ctx_talking(video, v.channel);
		if (i<0) return -EFAULT;
		d = video->it_context[i];

		if ((v.buffer<0) || (v.buffer>d->num_desc)) {
			PRINT(KERN_ERR, ohci->id, 
			      "buffer %d out of range",v.buffer);
			return -EFAULT;
		}

		switch(d->buffer_status[v.buffer]) {
		case VIDEO1394_BUFFER_READY:
			d->buffer_status[v.buffer]=VIDEO1394_BUFFER_FREE;
			return 0;
		case VIDEO1394_BUFFER_QUEUED:
#if 1
			while(d->buffer_status[v.buffer]!=
			      VIDEO1394_BUFFER_READY) {
				interruptible_sleep_on(&d->waitq);
				if(signal_pending(current)) return -EINTR;
			}
#else
			if (wait_event_interruptible(d->waitq, 
						     d->buffer_status[v.buffer]
						     == VIDEO1394_BUFFER_READY)
			    == -ERESTARTSYS)
				return -EINTR;
#endif
			d->buffer_status[v.buffer]=VIDEO1394_BUFFER_FREE;
			return 0;
		default:
			PRINT(KERN_ERR, ohci->id, 
			      "buffer %d is not queued",v.buffer);
			return -EFAULT;
		}
	}
	default:
		return -EINVAL;
	}
}

/*
 *	This maps the vmalloced and reserved buffer to user space.
 *
 *  FIXME: 
 *  - PAGE_READONLY should suffice!?
 *  - remap_page_range is kind of inefficient for page by page remapping.
 *    But e.g. pte_alloc() does not work in modules ... :-(
 */

int video1394_mmap(struct file *file, struct vm_area_struct *vma)
{
	struct video_card *video = 
		&video_cards[MINOR(file->f_dentry->d_inode->i_rdev)];
	struct ti_ohci *ohci;
	int res = -EINVAL;

	lock_kernel();
	ohci = video->ohci;
	PRINT(KERN_INFO, ohci->id, "mmap");
	if (video->current_ctx == NULL) {
		PRINT(KERN_ERR, ohci->id, "current iso context not set");
	} else
		res = do_iso_mmap(ohci, video->current_ctx, 
			   (char *)vma->vm_start, 
			   (unsigned long)(vma->vm_end-vma->vm_start));
	unlock_kernel();
	return res;
}

static int video1394_open(struct inode *inode, struct file *file)
{
	int i = MINOR(inode->i_rdev);

	if (i<0 || i>=num_of_video_cards) {
		PRINT(KERN_ERR, i, "ohci card %d not found", i);
		return -EIO;
	}

	V22_COMPAT_MOD_INC_USE_COUNT;

	PRINT(KERN_INFO, i, "open");

	return 0;
}

static int video1394_release(struct inode *inode, struct file *file)
{
	struct video_card *video = &video_cards[MINOR(inode->i_rdev)];
	struct ti_ohci *ohci= video->ohci;
	u64 mask;
	int i;

	lock_kernel();
	for (i=0;i<ohci->nb_iso_rcv_ctx-1;i++) 
		if (video->ir_context[i]) {
			mask = (u64)0x1<<video->ir_context[i]->channel;
			if (!(ohci->ISO_channel_usage & mask))
				PRINT(KERN_ERR, ohci->id, 
				      "channel %d is not being used", 
				      video->ir_context[i]->channel);
			else
				ohci->ISO_channel_usage &= ~mask;
			PRINT(KERN_INFO, ohci->id, 
			      "iso receive context %d stop listening "
			      "on channel %d", i+1, 
			      video->ir_context[i]->channel);
			free_dma_iso_ctx(&video->ir_context[i]);
		}
	
	for (i=0;i<ohci->nb_iso_xmit_ctx;i++) 
		if (video->it_context[i]) {
			mask = (u64)0x1<<video->it_context[i]->channel;
			if (!(ohci->ISO_channel_usage & mask))
				PRINT(KERN_ERR, ohci->id, 
				      "channel %d is not being used", 
				      video->it_context[i]->channel);
			else
				ohci->ISO_channel_usage &= ~mask;
			PRINT(KERN_INFO, ohci->id, 
			      "iso transmit context %d stop talking "
			      "on channel %d", i+1, 
			      video->it_context[i]->channel);
			free_dma_iso_ctx(&video->it_context[i]);
		}


	V22_COMPAT_MOD_DEC_USE_COUNT;

	PRINT(KERN_INFO, ohci->id, "release");
	unlock_kernel();
	return 0;
}

void irq_handler(int card, quadlet_t isoRecvIntEvent, 
		 quadlet_t isoXmitIntEvent)
{
	int i;
	struct video_card *video = &video_cards[card];
	
	DBGMSG(card, "Iso event Recv: %08x Xmit: %08x",
	       isoRecvIntEvent, isoXmitIntEvent);

	for (i=0;i<video->ohci->nb_iso_rcv_ctx-1;i++)
		if (isoRecvIntEvent & (1<<(i+1))) 
			wakeup_dma_ir_ctx(video->ohci,
					  video->ir_context[i]);

	for (i=0;i<video->ohci->nb_iso_xmit_ctx;i++)
		if (isoXmitIntEvent & (1<<i)) 
			wakeup_dma_it_ctx(video->ohci,
					  video->it_context[i]);
}

static struct file_operations video1394_fops=
{
        OWNER_THIS_MODULE
	ioctl:		video1394_ioctl,
	mmap:		video1394_mmap,
	open:		video1394_open,
	release:	video1394_release
};

static int video1394_init(int i, struct ti_ohci *ohci)
{
	struct video_card *video = &video_cards[i];

	if (ohci1394_register_video(ohci, &video_tmpl)<0) {
		PRINT(KERN_ERR, i, "register_video failed");
		return -1;
	}

	video->ohci = ohci;

	/* Iso receive dma contexts */
	video->ir_context = (struct dma_iso_ctx **)
		kmalloc((ohci->nb_iso_rcv_ctx-1)*
			sizeof(struct dma_iso_ctx *), GFP_KERNEL);
	if (video->ir_context) 
		memset(video->ir_context, 0,
		       (ohci->nb_iso_rcv_ctx-1)*sizeof(struct dma_iso_ctx *));
	else {
		PRINT(KERN_ERR, ohci->id, "Cannot allocate ir_context");
		return -1;
	}

	/* Iso transmit dma contexts */
	video->it_context = (struct dma_iso_ctx **)
		kmalloc(ohci->nb_iso_xmit_ctx *
			sizeof(struct dma_iso_ctx *), GFP_KERNEL);
	if (video->it_context) 
		memset(video->it_context, 0,
		       ohci->nb_iso_xmit_ctx * sizeof(struct dma_iso_ctx *));
	else {
		PRINT(KERN_ERR, ohci->id, "Cannot allocate it_context");
		return -1;
	}

	return 0;
}

static void remove_card(struct video_card *video)
{
	int i;

	ohci1394_unregister_video(video->ohci, &video_tmpl);

	/* Free the iso receive contexts */
	if (video->ir_context) {
		for (i=0;i<video->ohci->nb_iso_rcv_ctx-1;i++) {
			free_dma_iso_ctx(&video->ir_context[i]);
		}
		kfree(video->ir_context);
	}

	/* Free the iso transmit contexts */
	if (video->it_context) {
		for (i=0;i<video->ohci->nb_iso_xmit_ctx;i++) {
			free_dma_iso_ctx(&video->it_context[i]);
		}
		kfree(video->it_context);
	}
}

#ifdef MODULE

/* EXPORT_NO_SYMBOLS; */

MODULE_AUTHOR("Sebastien Rougeaux <[e-mail]>");
MODULE_DESCRIPTION("driver for digital video on OHCI board");
MODULE_SUPPORTED_DEVICE("video1394");

void cleanup_module(void)
{
	int i;
        unregister_chrdev(VIDEO1394_MAJOR, VIDEO1394_DRIVER_NAME);

	for (i=0; i<num_of_video_cards; i++)
		remove_card(&video_cards[i]);

	printk(KERN_INFO "removed " VIDEO1394_DRIVER_NAME " module\n");
}

int init_module(void)
{
	struct ti_ohci *ohci;
	int i;
	
	memset(video_cards, 0, MAX_OHCI1394_CARDS * sizeof(struct video_card));
	num_of_video_cards = 0;

	for (i=0; i<MAX_OHCI1394_CARDS; i++) {
		ohci=ohci1394_get_struct(i);
		if (ohci) {
			num_of_video_cards++;
			video1394_init(i, ohci);
		}
	}

	if (!num_of_video_cards) {
		PRINT_G(KERN_INFO, "no ohci card found... init failed");
		return -EIO;
	}

	if (register_chrdev(VIDEO1394_MAJOR, VIDEO1394_DRIVER_NAME, 
			    &video1394_fops)) {
		printk("video1394: unable to get major %d\n", 
		       VIDEO1394_MAJOR);
		return -EIO;
	}

	PRINT_G(KERN_INFO, "initialized with %d ohci cards", 
		num_of_video_cards);

	return 0;
}

#endif /* MODULE */