dabusb.c

基于S3CEB2410平台LINUX操作系统下 USB驱动源代码

	dbg("pending_io: %d", s->pending_io.counter);

	s->pending_io.counter = 0;
	return 0;
}

static int dabusb_startrek (pdabusb_t s)
{
	if (!s->got_mem && s->state != _started) {

		dbg("dabusb_startrek");

		if (dabusb_alloc_buffers (s) < 0)
			return -ENOMEM;
		dabusb_stop (s);
		s->state = _started;
		s->readptr = 0;
	}

	if (!list_empty (&s->free_buff_list)) {
		pbuff_t end;
		int ret;
		
	while (!dabusb_add_buf_tail (s, &s->rec_buff_list, &s->free_buff_list)) {

			dbg("submitting: end:%p s->rec_buff_list:%p", s->rec_buff_list.prev, &s->rec_buff_list);

			end = list_entry (s->rec_buff_list.prev, buff_t, buff_list);

			ret = usb_submit_urb (end->purb);
			if (ret) {
				err("usb_submit_urb returned:%d", ret);
				if (dabusb_add_buf_tail (s, &s->free_buff_list, &s->rec_buff_list))
					err("startrek: dabusb_add_buf_tail failed");
				break;
			}
			else
				atomic_inc (&s->pending_io);
		}
		dbg("pending_io: %d",s->pending_io.counter);
	}

	return 0;
}

static ssize_t dabusb_read (struct file *file, char *buf, size_t count, loff_t * ppos)
{
	pdabusb_t s = (pdabusb_t) file->private_data;
	unsigned long flags;
	unsigned ret = 0;
	int rem;
	int cnt;
	pbuff_t b;
	purb_t purb = NULL;

	dbg("dabusb_read");

	if (*ppos)
		return -ESPIPE;

	if (s->remove_pending)
		return -EIO;


	if (!s->usbdev)
		return -EIO;

	while (count > 0) {
		dabusb_startrek (s);

		spin_lock_irqsave (&s->lock, flags);

		if (list_empty (&s->rec_buff_list)) {

			spin_unlock_irqrestore(&s->lock, flags);

			err("error: rec_buf_list is empty");
			goto err;
		}
		
		b = list_entry (s->rec_buff_list.next, buff_t, buff_list);
		purb = b->purb;

		spin_unlock_irqrestore(&s->lock, flags);

		if (purb->status == -EINPROGRESS) {
			if (file->f_flags & O_NONBLOCK)		// return nonblocking
			 {
				if (!ret)
					ret = -EAGAIN;
				goto err;
			}

			interruptible_sleep_on (&s->wait);

			if (signal_pending (current)) {
				if (!ret)
					ret = -ERESTARTSYS;
				goto err;
			}

			spin_lock_irqsave (&s->lock, flags);

			if (list_empty (&s->rec_buff_list)) {
				spin_unlock_irqrestore(&s->lock, flags);
				err("error: still no buffer available.");
				goto err;
			}
			spin_unlock_irqrestore(&s->lock, flags);
			s->readptr = 0;
		}
		if (s->remove_pending) {
			ret = -EIO;
			goto err;
		}

		rem = purb->actual_length - s->readptr;		// set remaining bytes to copy

		if (count >= rem)
			cnt = rem;
		else
			cnt = count;

		dbg("copy_to_user:%p %p %d",buf, purb->transfer_buffer + s->readptr, cnt);

		if (copy_to_user (buf, purb->transfer_buffer + s->readptr, cnt)) {
			err("read: copy_to_user failed");
			if (!ret)
				ret = -EFAULT;
			goto err;
		}

		s->readptr += cnt;
		count -= cnt;
		buf += cnt;
		ret += cnt;

		if (s->readptr == purb->actual_length) {
			// finished, take next buffer
			if (dabusb_add_buf_tail (s, &s->free_buff_list, &s->rec_buff_list))
				err("read: dabusb_add_buf_tail failed");
			s->readptr = 0;
		}
	}
      err:			//up(&s->mutex);
	return ret;
}

static int dabusb_open (struct inode *inode, struct file *file)
{
	int devnum = MINOR (inode->i_rdev);
	pdabusb_t s;

	if (devnum < DABUSB_MINOR || devnum >= (DABUSB_MINOR + NRDABUSB))
		return -EIO;

	s = &dabusb[devnum - DABUSB_MINOR];

	dbg("dabusb_open");
	down (&s->mutex);

	while (!s->usbdev || s->opened) {
		up (&s->mutex);

		if (file->f_flags & O_NONBLOCK) {
			return -EBUSY;
		}
		schedule_timeout (HZ / 2);

		if (signal_pending (current)) {
			return -EAGAIN;
		}
		down (&s->mutex);
	}
	if (usb_set_interface (s->usbdev, _DABUSB_IF, 1) < 0) {
		err("set_interface failed");
		return -EINVAL;
	}
	s->opened = 1;
	up (&s->mutex);

	file->f_pos = 0;
	file->private_data = s;

	return 0;
}

static int dabusb_release (struct inode *inode, struct file *file)
{
	pdabusb_t s = (pdabusb_t) file->private_data;

	dbg("dabusb_release");

	lock_kernel();
	down (&s->mutex);
	dabusb_stop (s);
	dabusb_free_buffers (s);
	up (&s->mutex);

	if (!s->remove_pending) {
		if (usb_set_interface (s->usbdev, _DABUSB_IF, 0) < 0)
			err("set_interface failed");
	}
	else
		wake_up (&s->remove_ok);

	s->opened = 0;
	unlock_kernel();
	return 0;
}

static int dabusb_ioctl (struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
{
	pdabusb_t s = (pdabusb_t) file->private_data;
	pbulk_transfer_t pbulk;
	int ret = 0;
	int version = DABUSB_VERSION;

	dbg("dabusb_ioctl");

	if (s->remove_pending)
		return -EIO;

	down (&s->mutex);

	if (!s->usbdev) {
		up (&s->mutex);
		return -EIO;
	}

	switch (cmd) {

	case IOCTL_DAB_BULK:
		pbulk = (pbulk_transfer_t) kmalloc (sizeof (bulk_transfer_t), GFP_KERNEL);

		if (!pbulk) {
			ret = -ENOMEM;
			break;
		}

		if (copy_from_user (pbulk, (void *) arg, sizeof (bulk_transfer_t))) {
			ret = -EFAULT;
			kfree (pbulk);
			break;
		}

		ret=dabusb_bulk (s, pbulk);
		if(ret==0)
			ret = copy_to_user ((void *) arg, pbulk, sizeof (bulk_transfer_t));
		kfree (pbulk);
		break;

	case IOCTL_DAB_OVERRUNS:
		ret = put_user (s->overruns, (unsigned int *) arg);
		break;

	case IOCTL_DAB_VERSION:
		ret = put_user (version, (unsigned int *) arg);
		break;

	default:
		ret = -ENOIOCTLCMD;
		break;
	}
	up (&s->mutex);
	return ret;
}

static struct file_operations dabusb_fops =
{
	owner:		THIS_MODULE,
	llseek:		no_llseek,
	read:		dabusb_read,
	ioctl:		dabusb_ioctl,
	open:		dabusb_open,
	release:	dabusb_release,
};

static int dabusb_find_struct (void)
{
	int u;

	for (u = 0; u < NRDABUSB; u++) {
		pdabusb_t s = &dabusb[u];
		if (!s->usbdev)
			return u;
	}
	return -1;
}

/* --------------------------------------------------------------------- */
static void *dabusb_probe (struct usb_device *usbdev, unsigned int ifnum,
			   const struct usb_device_id *id)
{
	int devnum;
	pdabusb_t s;

	dbg("dabusb: probe: vendor id 0x%x, device id 0x%x ifnum:%d",
	  usbdev->descriptor.idVendor, usbdev->descriptor.idProduct, ifnum);

	/* We don't handle multiple configurations */
	if (usbdev->descriptor.bNumConfigurations != 1)
		return NULL;

	if (ifnum != _DABUSB_IF && usbdev->descriptor.idProduct == 0x9999)
		return NULL;

	devnum = dabusb_find_struct ();
	if (devnum == -1)
		return NULL;

	s = &dabusb[devnum];

	down (&s->mutex);
	s->remove_pending = 0;
	s->usbdev = usbdev;

	if (usb_set_configuration (usbdev, usbdev->config[0].bConfigurationValue) < 0) {
		err("set_configuration failed");
		goto reject;
	}
	if (usbdev->descriptor.idProduct == 0x2131) {
		dabusb_loadmem (s, NULL);
		goto reject;
	}
	else {
		dabusb_fpga_download (s, NULL);

		if (usb_set_interface (s->usbdev, _DABUSB_IF, 0) < 0) {
			err("set_interface failed");
			goto reject;
		}
	}
	dbg("bound to interface: %d", ifnum);
	up (&s->mutex);
	MOD_INC_USE_COUNT;
	return s;

      reject:
	up (&s->mutex);
	s->usbdev = NULL;
	return NULL;
}

static void dabusb_disconnect (struct usb_device *usbdev, void *ptr)
{
	pdabusb_t s = (pdabusb_t) ptr;

	dbg("dabusb_disconnect");

	s->remove_pending = 1;
	wake_up (&s->wait);
	if (s->state == _started)
		sleep_on (&s->remove_ok);
	s->usbdev = NULL;
	s->overruns = 0;
	MOD_DEC_USE_COUNT;
}

static struct usb_device_id dabusb_ids [] = {
	{ USB_DEVICE(0x0547, 0x2131) },
	{ USB_DEVICE(0x0547, 0x9999) },
	{ }						/* Terminating entry */
};

MODULE_DEVICE_TABLE (usb, dabusb_ids);

static struct usb_driver dabusb_driver =
{
	name:		"dabusb",
	probe:		dabusb_probe,
	disconnect:	dabusb_disconnect,
	fops:		&dabusb_fops,
	minor:		DABUSB_MINOR,
	id_table:	dabusb_ids,
};

/* --------------------------------------------------------------------- */

static int __init dabusb_init (void)
{
	unsigned u;

	/* initialize struct */
	for (u = 0; u < NRDABUSB; u++) {
		pdabusb_t s = &dabusb[u];
		memset (s, 0, sizeof (dabusb_t));
		init_MUTEX (&s->mutex);
		s->usbdev = NULL;
		s->total_buffer_size = buffers;
		init_waitqueue_head (&s->wait);
		init_waitqueue_head (&s->remove_ok);
		spin_lock_init (&s->lock);
		INIT_LIST_HEAD (&s->free_buff_list);
		INIT_LIST_HEAD (&s->rec_buff_list);
	}

	/* register misc device */
	if (usb_register(&dabusb_driver))
		return -1;

	dbg("dabusb_init: driver registered");

	info(DRIVER_VERSION ":" DRIVER_DESC);

	return 0;
}

static void __exit dabusb_cleanup (void)
{
	dbg("dabusb_cleanup");

	usb_deregister (&dabusb_driver);
}

/* --------------------------------------------------------------------- */

MODULE_AUTHOR( DRIVER_AUTHOR );
MODULE_DESCRIPTION( DRIVER_DESC );
MODULE_LICENSE("GPL");

MODULE_PARM (buffers, "i");
MODULE_PARM_DESC (buffers, "Number of buffers (default=256)");

module_init (dabusb_init);
module_exit (dabusb_cleanup);

/* --------------------------------------------------------------------- */