sn9c102_core.c

优龙2410linux2.6.8内核源代码

	kfree(cam->control_buffer);
}

/*****************************************************************************/

static int sn9c102_open(struct inode* inode, struct file* filp)
{
	struct sn9c102_device* cam;
	int err = 0;

	/* This the only safe way to prevent race conditions with disconnect */
	if (!down_read_trylock(&sn9c102_disconnect))
		return -ERESTARTSYS;

	cam = video_get_drvdata(video_devdata(filp));

	if (down_interruptible(&cam->dev_sem)) {
		up_read(&sn9c102_disconnect);
		return -ERESTARTSYS;
	}

	if (cam->users) {
		DBG(2, "Device /dev/video%d is busy...", cam->v4ldev->minor)
		if ((filp->f_flags & O_NONBLOCK) ||
		    (filp->f_flags & O_NDELAY)) {
			err = -EWOULDBLOCK;
			goto out;
		}
		up(&cam->dev_sem);
		err = wait_event_interruptible_exclusive(cam->open,
		                                  cam->state & DEV_DISCONNECTED
		                                         || !cam->users);
		if (err) {
			up_read(&sn9c102_disconnect);
			return err;
		}
		if (cam->state & DEV_DISCONNECTED) {
			up_read(&sn9c102_disconnect);
			return -ENODEV;
		}
		down(&cam->dev_sem);
	}


	if (cam->state & DEV_MISCONFIGURED) {
		err = sn9c102_init(cam);
		if (err) {
			DBG(1, "Initialization failed again. "
			       "I will retry on next open().")
			goto out;
		}
		cam->state &= ~DEV_MISCONFIGURED;
	}

	if ((err = sn9c102_start_transfer(cam)))
		goto out;

	filp->private_data = cam;
	cam->users++;
	cam->io = IO_NONE;
	cam->stream = STREAM_OFF;
	cam->nbuffers = 0;
	cam->frame_count = 0;
	sn9c102_empty_framequeues(cam);

	DBG(3, "Video device /dev/video%d is open", cam->v4ldev->minor)

out:
	up(&cam->dev_sem);
	up_read(&sn9c102_disconnect);
	return err;
}


static int sn9c102_release(struct inode* inode, struct file* filp)
{
	struct sn9c102_device* cam = video_get_drvdata(video_devdata(filp));

	down(&cam->dev_sem); /* prevent disconnect() to be called */

	sn9c102_stop_transfer(cam);

	sn9c102_release_buffers(cam);

	if (cam->state & DEV_DISCONNECTED) {
		sn9c102_release_resources(cam);
		up(&cam->dev_sem);
		kfree(cam);
		return 0;
	}

	cam->users--;
	wake_up_interruptible_nr(&cam->open, 1);

	DBG(3, "Video device /dev/video%d closed", cam->v4ldev->minor)

	up(&cam->dev_sem);

	return 0;
}


static ssize_t
sn9c102_read(struct file* filp, char __user * buf, size_t count, loff_t* f_pos)
{
	struct sn9c102_device* cam = video_get_drvdata(video_devdata(filp));
	struct sn9c102_frame_t* f, * i;
	unsigned long lock_flags;
	int err = 0;

	if (down_interruptible(&cam->fileop_sem))
		return -ERESTARTSYS;

	if (cam->state & DEV_DISCONNECTED) {
		DBG(1, "Device not present")
		up(&cam->fileop_sem);
		return -ENODEV;
	}

	if (cam->state & DEV_MISCONFIGURED) {
		DBG(1, "The camera is misconfigured. Close and open it again.")
		up(&cam->fileop_sem);
		return -EIO;
	}

	if (cam->io == IO_MMAP) {
		DBG(3, "Close and open the device again to choose "
		       "the read method")
		up(&cam->fileop_sem);
		return -EINVAL;
	}

	if (cam->io == IO_NONE) {
		if (!sn9c102_request_buffers(cam, 2)) {
			DBG(1, "read() failed, not enough memory")
			up(&cam->fileop_sem);
			return -ENOMEM;
		}
		cam->io = IO_READ;
		cam->stream = STREAM_ON;
		sn9c102_queue_unusedframes(cam);
	}

	if (!count) {
		up(&cam->fileop_sem);
		return 0;
	}

	if (list_empty(&cam->outqueue)) {
		if (filp->f_flags & O_NONBLOCK) {
			up(&cam->fileop_sem);
			return -EAGAIN;
		}
		err = wait_event_interruptible
		      ( cam->wait_frame, 
		        (!list_empty(&cam->outqueue)) ||
		        (cam->state & DEV_DISCONNECTED) );
		if (err) {
			up(&cam->fileop_sem);
			return err;
		}
		if (cam->state & DEV_DISCONNECTED) {
			up(&cam->fileop_sem);
			return -ENODEV;
		}
	}

	f = list_entry(cam->outqueue.prev, struct sn9c102_frame_t, frame);

	spin_lock_irqsave(&cam->queue_lock, lock_flags);
	list_for_each_entry(i, &cam->outqueue, frame)
		i->state = F_UNUSED;
	INIT_LIST_HEAD(&cam->outqueue);
	spin_unlock_irqrestore(&cam->queue_lock, lock_flags);

	sn9c102_queue_unusedframes(cam);

	if (count > f->buf.length)
		count = f->buf.length;

	if (copy_to_user(buf, f->bufmem, count)) {
		up(&cam->fileop_sem);
		return -EFAULT;
	}
	*f_pos += count;

	PDBGG("Frame #%lu, bytes read: %zu", (unsigned long)f->buf.index,count)

	up(&cam->fileop_sem);

	return count;
}


static unsigned int sn9c102_poll(struct file *filp, poll_table *wait)
{
	struct sn9c102_device* cam = video_get_drvdata(video_devdata(filp));
	unsigned int mask = 0;

	if (down_interruptible(&cam->fileop_sem))
		return POLLERR;

	if (cam->state & DEV_DISCONNECTED) {
		DBG(1, "Device not present")
		goto error;
	}

	if (cam->state & DEV_MISCONFIGURED) {
		DBG(1, "The camera is misconfigured. Close and open it again.")
		goto error;
	}

	if (cam->io == IO_NONE) {
		if (!sn9c102_request_buffers(cam, 2)) {
			DBG(1, "poll() failed, not enough memory")
			goto error;
		}
		cam->io = IO_READ;
		cam->stream = STREAM_ON;
	}

	if (cam->io == IO_READ)
		sn9c102_queue_unusedframes(cam);

	poll_wait(filp, &cam->wait_frame, wait);

	if (!list_empty(&cam->outqueue))
		mask |= POLLIN | POLLRDNORM;

	up(&cam->fileop_sem);

	return mask;

error:
	up(&cam->fileop_sem);
	return POLLERR;
}


static void sn9c102_vm_open(struct vm_area_struct* vma)
{
	struct sn9c102_frame_t* f = vma->vm_private_data;
	f->vma_use_count++;
}


static void sn9c102_vm_close(struct vm_area_struct* vma)
{
	/* NOTE: buffers are not freed here */
	struct sn9c102_frame_t* f = vma->vm_private_data;
	f->vma_use_count--;
}


static struct vm_operations_struct sn9c102_vm_ops = {
	.open = sn9c102_vm_open,
	.close = sn9c102_vm_close,
};


static int sn9c102_mmap(struct file* filp, struct vm_area_struct *vma)
{
	struct sn9c102_device* cam = video_get_drvdata(video_devdata(filp));
	unsigned long size = vma->vm_end - vma->vm_start,
	              start = vma->vm_start,
	              pos,
	              page;
	u32 i;

	if (down_interruptible(&cam->fileop_sem))
		return -ERESTARTSYS;

	if (cam->state & DEV_DISCONNECTED) {
		DBG(1, "Device not present")
		up(&cam->fileop_sem);
		return -ENODEV;
	}

	if (cam->state & DEV_MISCONFIGURED) {
		DBG(1, "The camera is misconfigured. Close and open it again.")
		up(&cam->fileop_sem);
		return -EIO;
	}

	if (cam->io != IO_MMAP || !(vma->vm_flags & VM_WRITE) ||
	    size != PAGE_ALIGN(cam->frame[0].buf.length)) {
		up(&cam->fileop_sem);
		return -EINVAL;
	}

	for (i = 0; i < cam->nbuffers; i++) {
		if ((cam->frame[i].buf.m.offset>>PAGE_SHIFT) == vma->vm_pgoff)
			break;
	}
	if (i == cam->nbuffers) {
		up(&cam->fileop_sem);
		return -EINVAL;
	}

	pos = (unsigned long)cam->frame[i].bufmem;
	while (size > 0) { /* size is page-aligned */
		page = kvirt_to_pa(pos);
		if (remap_page_range(vma, start, page, PAGE_SIZE, 
		                     vma->vm_page_prot)) {
			up(&cam->fileop_sem);
			return -EAGAIN;
		}
		start += PAGE_SIZE;
		pos += PAGE_SIZE;
		size -= PAGE_SIZE;
	}

	vma->vm_ops = &sn9c102_vm_ops;
	vma->vm_flags &= ~VM_IO; /* not I/O memory */
	vma->vm_flags |= VM_RESERVED; /* avoid to swap out this VMA */
	vma->vm_private_data = &cam->frame[i];

	sn9c102_vm_open(vma);

	up(&cam->fileop_sem);

	return 0;
}


static int sn9c102_v4l2_ioctl(struct inode* inode, struct file* filp,
                              unsigned int cmd, void __user * arg)
{
	struct sn9c102_device* cam = video_get_drvdata(video_devdata(filp));

	switch (cmd) {

	case VIDIOC_QUERYCAP:
	{
		struct v4l2_capability cap = {
			.driver = "sn9c102",
			.version = SN9C102_MODULE_VERSION_CODE,
			.capabilities = V4L2_CAP_VIDEO_CAPTURE | 
			                V4L2_CAP_READWRITE |
		 	                V4L2_CAP_STREAMING,
		};

		strlcpy(cap.card, cam->v4ldev->name, sizeof(cap.card));
		strlcpy(cap.bus_info, cam->dev.bus_id, sizeof(cap.bus_info));

		if (copy_to_user(arg, &cap, sizeof(cap)))
			return -EFAULT;

		return 0;
	}

	case VIDIOC_ENUMINPUT:
	{
		struct v4l2_input i;

		if (copy_from_user(&i, arg, sizeof(i)))
			return -EFAULT;

		if (i.index)
			return -EINVAL;

		memset(&i, 0, sizeof(i));
		strcpy(i.name, "USB");

		if (copy_to_user(arg, &i, sizeof(i)))
			return -EFAULT;

		return 0;
	}

	case VIDIOC_G_INPUT:
	case VIDIOC_S_INPUT:
	{
		int index;

		if (copy_from_user(&index, arg, sizeof(index)))
			return -EFAULT;

		if (index != 0)
			return -EINVAL;

		return 0;
	}

	case VIDIOC_QUERYCTRL:
	{
		struct sn9c102_sensor* s = cam->sensor;
		struct v4l2_queryctrl qc;
		u8 i, n;

		if (copy_from_user(&qc, arg, sizeof(qc)))
			return -EFAULT;

		n = sizeof(s->qctrl) / sizeof(s->qctrl[0]);
		for (i = 0; i < n; i++)
			if (qc.id && qc.id == s->qctrl[i].id) {
				memcpy(&qc, &(s->qctrl[i]), sizeof(qc));
				if (copy_to_user(arg, &qc, sizeof(qc)))
					return -EFAULT;
				return 0;
			}

		return -EINVAL;
	}

	case VIDIOC_G_CTRL:
	{
		struct sn9c102_sensor* s = cam->sensor;
		struct v4l2_control ctrl;
		int err = 0;

		if (!s->get_ctrl)
			return -EINVAL;

		if (copy_from_user(&ctrl, arg, sizeof(ctrl)))
			return -EFAULT;

		err = s->get_ctrl(cam, &ctrl);

		if (copy_to_user(arg, &ctrl, sizeof(ctrl)))
			return -EFAULT;

		return err;
	}

	case VIDIOC_S_CTRL:
	{
		struct sn9c102_sensor* s = cam->sensor;
		struct v4l2_control ctrl;
		u8 i, n;
		int err = 0;

		if (!s->set_ctrl)
			return -EINVAL;

		if (copy_from_user(&ctrl, arg, sizeof(ctrl)))
			return -EFAULT;

		if ((err = s->set_ctrl(cam, &ctrl)))
			return err;

		n = sizeof(s->qctrl) / sizeof(s->qctrl[0]);
		for (i = 0; i < n; i++)
			if (ctrl.id == s->qctrl[i].id) {
				s->_qctrl[i].default_value = ctrl.value;
				break;
			}

		return 0;
	}

	case VIDIOC_CROPCAP:
	{
		struct v4l2_cropcap* cc = &(cam->sensor->cropcap);

		cc->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
		cc->pixelaspect.numerator = 1;
		cc->pixelaspect.denominator = 1;

		if (copy_to_user(arg, cc, sizeof(*cc)))
			return -EFAULT;

		return 0;
	}

	case VIDIOC_G_CROP:
	{
		struct sn9c102_sensor* s = cam->sensor;
		struct v4l2_crop crop = {
			.type = V4L2_BUF_TYPE_VIDEO_CAPTURE,
		};

		memcpy(&(crop.c), &(s->_rect), sizeof(struct v4l2_rect));

		if (copy_to_user(arg, &crop, sizeof(crop)))
			return -EFAULT;

		return 0;
	}

	case VIDIOC_S_CROP:
	{
		struct sn9c102_sensor* s = cam->sensor;
		struct v4l2_crop crop;
		struct v4l2_rect* rect;
		struct v4l2_rect* bounds = &(s->cropcap.bounds);
		struct v4l2_pix_format* pix_format = &(s->pix_format);
		u8 scale;
		const enum sn9c102_stream_state stream = cam->stream;
		const u32 nbuffers = cam->nbuffers;
		u32 i;
		int err = 0;

		if (copy_from_user(&crop, arg, sizeof(crop)))
			return -EFAULT;

		rect = &(crop.c);

		if (crop.type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
			return -EINVAL;

		for (i = 0; i < cam->nbuffers; i++)
			if (cam->frame[i].vma_use_count) {
				DBG(3, "VIDIOC_S_CROP failed. "
				       "Unmap the buffers first.")
				return -EINVAL;
			}

		if (rect->width < 16)
			rect->width = 16;
		if (rect->height < 16)
			rect->height = 16;
		if (rect->width > bounds->width)
			rect->width = bounds->width;
		if (rect->height > bounds->height)
			rect->height = bounds->height;
		if (rect->left < bounds->left)
			rect->left = bounds->left;
		if (rect->top < bounds->top)
			rect->top = bounds->top;
		if (rect->left + rect->width > bounds->left + bounds->width)
			rect->left = bounds->left+bounds->width - rect->width;
		if (rect->top + rect->height > bounds->top + bounds->height)
			rect->top = bounds->top+bounds->height - rect->height;

		rect->width &= ~15L;
		rect->height &= ~15L;

		{ /* calculate the scaling factor */
			u32 a, b;
			a = rect->width * rect->height;
			b = pix_format->width * pix_format->height;
			scale = b ? (u8)((a / b) <= 1 ? 1 : ((a / b) == 3 ? 2 :
			            ((a / b) > 4 ? 4 : (a / b)))) : 1;
		}

		if (cam->stream == STREAM_ON) {
			cam->stream = STREAM_INTERRUPT;
			err = wait_event_interruptible
			      ( cam->wait_stream, 
			        (cam->stream == STREAM_OFF) ||
			        (cam->state & DEV_DISCONNECTED) );
			if (err) {
				cam->state |= DEV_MISCONFIGURED;
				DBG(1, "The camera is misconfigured. To use "
				       "it, close and open /dev/video%d "
				       "again.", cam->v4ldev->minor)
				return err;
			}
			if (cam->state & DEV_DISCONNECTED)
				return -ENODEV;
		}

		if (copy_to_user(arg, &crop, sizeof(crop))) {
			cam->stream = stream;
			return -EFAULT;
		}

		sn9c102_release_buffers(cam);

		err = sn9c102_set_crop(cam, rect);
		if (s->set_crop)
			err += s->set_crop(cam, rect);
		err += sn9c102_set_scale(cam, scale);

		if (err) { /* atomic, no rollback in ioctl() */
			cam->state |= DEV_MISCONFIGURED;
			DBG(1, "VIDIOC_S_CROP failed because of hardware "
			       "problems. To use the camera, close and open "
			       "/dev/video%d again.", cam->v4ldev->minor)
			return err;
		}

		s->pix_format.width = rect->width/scale;
		s->pix_format.height = rect->height/scale;
		memcpy(&(s->_rect), rect, sizeof(*rect));

		if (nbuffers != sn9c102_request_buffers(cam, nbuffers)) {
			cam->state |= DEV_MISCONFIGURED;
			DBG(1, "VIDIOC_S_CROP failed because of not enough "
			       "memory. To use the camera, close and open "
			       "/dev/video%d again.", cam->v4ldev->minor)
			return -ENOMEM;
		}

		cam->stream = stream;

		return 0;
	}

	case VIDIOC_ENUM_FMT:
	{
		struct sn9c102_sensor* s = cam->sensor;
		struct v4l2_fmtdesc fmtd;

		if (copy_from_user(&fmtd, arg, sizeof(fmtd)))
			return -EFAULT;

		if (fmtd.index != 0)
			return -EINVAL;

		memset(&fmtd, 0, sizeof(fmtd));

		fmtd.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
		strcpy(fmtd.description, "bayer rgb");
		fmtd.pixelformat = s->pix_format.pixelformat;

		if (copy_to_user(arg, &fmtd, sizeof(fmtd)))
			return -EFAULT;