video1394.c

这个是uClinux下的ieee1394驱动

		d->buffer_status[v.buffer]=VIDEO1394_BUFFER_QUEUED;

		if (d->last_buffer>=0) 
			d->ir_prg[d->last_buffer][d->nb_cmd-1].branchAddress = 
				cpu_to_le32((virt_to_bus(&(d->ir_prg[v.buffer][0].control)) 
				 & 0xfffffff0) | 0x1);

		d->last_buffer = v.buffer;

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

		spin_unlock_irqrestore(&d->lock,flags);

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

			/* Tell the controller where the first program is */
			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:
	case VIDEO1394_LISTEN_POLL_BUFFER:
	{
		struct video1394_wait v;
		struct dma_iso_ctx *d;
		int i;

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

		d = find_ctx(&ctx->context_list, OHCI_ISO_RECEIVE, v.channel);

		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 (cmd == VIDEO1394_LISTEN_POLL_BUFFER) {
			    /* for polling, return error code EINTR */
			    spin_unlock_irqrestore(&d->lock, flags);
			    return -EINTR;
			}

#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;
		}

		/* set time of buffer */
		v.filltime = d->buffer_time[v.buffer];
//		printk("Buffer %d time %d\n", v.buffer, (d->buffer_time[v.buffer]).tv_usec);

		/*
		 * 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 video1394_queue_variable qv;
		struct dma_iso_ctx *d;

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

		d = find_ctx(&ctx->context_list, OHCI_ISO_TRANSMIT, v.channel);

		if ((v.buffer<0) || (v.buffer>d->num_desc)) {
			PRINT(KERN_ERR, ohci->id, 
			      "Buffer %d out of range",v.buffer);
			return -EFAULT;
		}
		
		if (d->flags & VIDEO1394_VARIABLE_PACKET_SIZE) {
			if (copy_from_user(&qv, (void *)arg, sizeof(qv))) 
				return -EFAULT;
			if (!access_ok(VERIFY_READ, qv.packet_sizes, 
				       d->nb_cmd * sizeof(unsigned int))) {
				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;
		}
		
		if (d->flags & VIDEO1394_VARIABLE_PACKET_SIZE) {
			initialize_dma_it_prg_var_packet_queue(
				d, v.buffer, qv.packet_sizes,
				ohci);
		}

		d->buffer_status[v.buffer]=VIDEO1394_BUFFER_QUEUED;

		if (d->last_buffer>=0) {
			d->it_prg[d->last_buffer]
				[ d->last_used_cmd[d->last_buffer]
					].end.branchAddress = 
				cpu_to_le32((virt_to_bus(&(d->it_prg[v.buffer][0].begin.control)) 
				 & 0xfffffff0) | 0x3);

			d->it_prg[d->last_buffer]
				[d->last_used_cmd[d->last_buffer]
					].begin.branchAddress = 
				cpu_to_le32((virt_to_bus(&(d->it_prg[v.buffer][0].begin.control)) 
				 & 0xfffffff0) | 0x3);
			d->next_buffer[d->last_buffer] = v.buffer;
		}
		d->last_buffer = v.buffer;
		d->next_buffer[d->last_buffer] = -1;

		d->it_prg[d->last_buffer][d->last_used_cmd[d->last_buffer]].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);
			put_timestamp(ohci, d, d->last_buffer);

			/* 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);
				put_timestamp(ohci, d, d->last_buffer);
				reg_write(ohci, d->ctrlSet, 0x1000);
			}
		}
		return 0;
		
	}
	case VIDEO1394_TALK_WAIT_BUFFER:
	{
		struct video1394_wait v;
		struct dma_iso_ctx *d;

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

		d = find_ctx(&ctx->context_list, OHCI_ISO_TRANSMIT, v.channel);

		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 file_ctx *ctx = (struct file_ctx *)file->private_data;
	struct video_card *video = ctx->video;
	struct ti_ohci *ohci = video->ohci;
	int res = -EINVAL;

	lock_kernel();
	ohci = video->ohci;

	if (ctx->current_ctx == NULL) {
		PRINT(KERN_ERR, ohci->id, "Current iso context not set");
	} else
		res = do_iso_mmap(ohci, ctx->current_ctx, vma);
	unlock_kernel();
	return res;
}

static int video1394_open(struct inode *inode, struct file *file)
{
	int i = ieee1394_file_to_instance(file);
	unsigned long flags;
	struct video_card *video = NULL;
	struct list_head *lh;
	struct file_ctx *ctx;

	spin_lock_irqsave(&video1394_cards_lock, flags);
	list_for_each(lh, &video1394_cards) {
		struct video_card *p = list_entry(lh, struct video_card, list);
		if (p->id == i) {
			video = p;
			break;
		}
	}
	spin_unlock_irqrestore(&video1394_cards_lock, flags);

        if (video == NULL)
                return -EIO;

	ctx = kmalloc(sizeof(struct file_ctx), GFP_KERNEL);
	if (ctx == NULL)  {
		PRINT(KERN_ERR, video->ohci->id, "Cannot malloc file_ctx");
		return -ENOMEM;
	}

	memset(ctx, 0, sizeof(struct file_ctx));
	ctx->video = video;
	INIT_LIST_HEAD(&ctx->context_list);
	ctx->current_ctx = NULL;
	file->private_data = ctx;

	return 0;
}

static int video1394_release(struct inode *inode, struct file *file)
{
	struct file_ctx *ctx = (struct file_ctx *)file->private_data;
	struct video_card *video = ctx->video;
	struct ti_ohci *ohci = video->ohci;
	struct list_head *lh, *next;
	u64 mask;

	lock_kernel();
	list_for_each_safe(lh, next, &ctx->context_list) {
		struct dma_iso_ctx *d;
		d = list_entry(lh, struct dma_iso_ctx, link);
		mask = (u64) 1 << d->channel;
		
		if (!(ohci->ISO_channel_usage & mask))
			PRINT(KERN_ERR, ohci->id, "On release: Channel %d "
			      "is not being used", d->channel);
		else
			ohci->ISO_channel_usage &= ~mask;
		PRINT(KERN_INFO, ohci->id, "On release: Iso %s context "
		      "%d stop listening on channel %d",
		      d->type == OHCI_ISO_RECEIVE ? "receive" : "transmit",
		      d->ctx, d->channel);
		free_dma_iso_ctx(d);
	}

	kfree(ctx);
	file->private_data = NULL;
	
	unlock_kernel();
	return 0;
}

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(struct ti_ohci *ohci)
{
	struct video_card *video;
	unsigned long flags;
	char name[16];
	int minor;

	video = kmalloc(sizeof(struct video_card), GFP_KERNEL);
	if (video == NULL) {
		PRINT(KERN_ERR, ohci->id, "Cannot allocate video_card");
		return -1;
	}

	memset(video, 0, sizeof(struct video_card));

	spin_lock_irqsave(&video1394_cards_lock, flags);
	INIT_LIST_HEAD(&video->list);
	list_add_tail(&video->list, &video1394_cards);
	spin_unlock_irqrestore(&video1394_cards_lock, flags);

	video->id = ohci->id;
	video->ohci = ohci;

	sprintf(name, "%d", video->id);
	minor = IEEE1394_MINOR_BLOCK_VIDEO1394 * 16 + video->id;
	video->devfs = devfs_register(devfs_handle, name,
				      DEVFS_FL_AUTO_OWNER,
				      IEEE1394_MAJOR, minor,
				      S_IFCHR | S_IRUSR | S_IWUSR,
				      &video1394_fops, NULL);

	return 0;
}

/* Must be called under spinlock */
static void remove_card(struct video_card *video)
{
	devfs_unregister(video->devfs);
	list_del(&video->list);

	kfree(video);
}

static void video1394_remove_host (struct hpsb_host *host)
{
	struct ti_ohci *ohci;
	unsigned long flags;
	struct list_head *lh, *next;
	struct video_card *p;

	/* We only work with the OHCI-1394 driver */
	if (strcmp(host->driver->name, OHCI1394_DRIVER_NAME))
		return;

	ohci = (struct ti_ohci *)host->hostdata;

        spin_lock_irqsave(&video1394_cards_lock, flags);
	list_for_each_safe(lh, next, &video1394_cards) {
		p = list_entry(lh, struct video_card, list);
		if (p->ohci == ohci) {
			remove_card(p);
			break;
		}
	}
	spin_unlock_irqrestore(&video1394_cards_lock, flags);

	return;
}

static void video1394_add_host (struct hpsb_host *host)
{
	struct ti_ohci *ohci;

	/* We only work with the OHCI-1394 driver */
	if (strcmp(host->driver->name, OHCI1394_DRIVER_NAME))
		return;

	ohci = (struct ti_ohci *)host->hostdata;

	video1394_init(ohci);
	
	return;
}

static struct hpsb_highlevel_ops hl_ops = {
	.add_host =	video1394_add_host,
	.remove_host =	video1394_remove_host,
};

MODULE_AUTHOR("Sebastien Rougeaux <[e-mail]>");
MODULE_DESCRIPTION("driver for digital video on OHCI board");
MODULE_SUPPORTED_DEVICE(VIDEO1394_DRIVER_NAME);
MODULE_LICENSE("GPL");

static void __exit video1394_exit_module (void)
{
	hpsb_unregister_highlevel (hl_handle);

	devfs_unregister(devfs_handle);
	ieee1394_unregister_chardev(IEEE1394_MINOR_BLOCK_VIDEO1394);
	
	PRINT_G(KERN_INFO, "Removed " VIDEO1394_DRIVER_NAME " module");
}

static int __init video1394_init_module (void)
{
	if (ieee1394_register_chardev(IEEE1394_MINOR_BLOCK_VIDEO1394,
				      THIS_MODULE, &video1394_fops)) {
		PRINT_G(KERN_ERR, "video1394: unable to get minor device block");
 		return -EIO;
 	}
	
#if LINUX_VERSION_CODE < KERNEL_VERSION(2,3,0)
	devfs_handle = devfs_mk_dir(NULL, VIDEO1394_DRIVER_NAME,
			strlen(VIDEO1394_DRIVER_NAME), NULL);
#else
	devfs_handle = devfs_mk_dir(NULL, VIDEO1394_DRIVER_NAME, NULL);
#endif

	hl_handle = hpsb_register_highlevel (VIDEO1394_DRIVER_NAME, &hl_ops);
	if (hl_handle == NULL) {
		PRINT_G(KERN_ERR, "No more memory for driver\n");
		devfs_unregister(devfs_handle);
		ieee1394_unregister_chardev(IEEE1394_MINOR_BLOCK_VIDEO1394);
		return -ENOMEM;
	}

	PRINT_G(KERN_INFO, "Installed " VIDEO1394_DRIVER_NAME " module");
	return 0;
}

module_init(video1394_init_module);
module_exit(video1394_exit_module);