em28xx-video.c

LINUX 2.6.17.4的源码

		     (dev->state & DEV_DISCONNECTED));
		if (ret) {
			mutex_unlock(&dev->fileop_lock);
			return ret;
		}
		if (dev->state & DEV_DISCONNECTED) {
			mutex_unlock(&dev->fileop_lock);
			return -ENODEV;
		}
	}

	f = list_entry(dev->outqueue.prev, struct em28xx_frame_t, frame);

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

	em28xx_queue_unusedframes(dev);

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

	if (copy_to_user(buf, f->bufmem, count)) {
		mutex_unlock(&dev->fileop_lock);
		return -EFAULT;
	}
	*f_pos += count;

	mutex_unlock(&dev->fileop_lock);

	return count;
}

/*
 * em28xx_v4l2_poll()
 * will allocate buffers when called for the first time
 */
static unsigned int em28xx_v4l2_poll(struct file *filp, poll_table * wait)
{
	unsigned int mask = 0;
	struct em28xx *dev = filp->private_data;

	if (mutex_lock_interruptible(&dev->fileop_lock))
		return POLLERR;

	if (dev->state & DEV_DISCONNECTED) {
		em28xx_videodbg("device not present\n");
	} else if (dev->state & DEV_MISCONFIGURED) {
		em28xx_videodbg("device is misconfigured; close and open it again\n");
	} else {
		if (dev->io == IO_NONE) {
			if (!em28xx_request_buffers
			    (dev, EM28XX_NUM_READ_FRAMES)) {
				em28xx_warn
				    ("poll() failed, not enough memory\n");
			} else {
				dev->io = IO_READ;
				dev->stream = STREAM_ON;
			}
		}

		if (dev->io == IO_READ) {
			em28xx_queue_unusedframes(dev);
			poll_wait(filp, &dev->wait_frame, wait);

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

			mutex_unlock(&dev->fileop_lock);

			return mask;
		}
	}

	mutex_unlock(&dev->fileop_lock);
	return POLLERR;
}

/*
 * em28xx_vm_open()
 */
static void em28xx_vm_open(struct vm_area_struct *vma)
{
	struct em28xx_frame_t *f = vma->vm_private_data;
	f->vma_use_count++;
}

/*
 * em28xx_vm_close()
 */
static void em28xx_vm_close(struct vm_area_struct *vma)
{
	/* NOTE: buffers are not freed here */
	struct em28xx_frame_t *f = vma->vm_private_data;
	f->vma_use_count--;
}

static struct vm_operations_struct em28xx_vm_ops = {
	.open = em28xx_vm_open,
	.close = em28xx_vm_close,
};

/*
 * em28xx_v4l2_mmap()
 */
static int em28xx_v4l2_mmap(struct file *filp, struct vm_area_struct *vma)
{
	unsigned long size = vma->vm_end - vma->vm_start,
	    start = vma->vm_start;
	void *pos;
	u32 i;

	struct em28xx *dev = filp->private_data;

	if (mutex_lock_interruptible(&dev->fileop_lock))
		return -ERESTARTSYS;

	if (dev->state & DEV_DISCONNECTED) {
		em28xx_videodbg("mmap: device not present\n");
		mutex_unlock(&dev->fileop_lock);
		return -ENODEV;
	}

	if (dev->state & DEV_MISCONFIGURED) {
		em28xx_videodbg ("mmap: Device is misconfigured; close and "
						"open it again\n");
		mutex_unlock(&dev->fileop_lock);
		return -EIO;
	}

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

	for (i = 0; i < dev->num_frames; i++) {
		if ((dev->frame[i].buf.m.offset >> PAGE_SHIFT) == vma->vm_pgoff)
			break;
	}
	if (i == dev->num_frames) {
		em28xx_videodbg("mmap: user supplied mapping address is out of range\n");
		mutex_unlock(&dev->fileop_lock);
		return -EINVAL;
	}

	/* VM_IO is eventually going to replace PageReserved altogether */
	vma->vm_flags |= VM_IO;
	vma->vm_flags |= VM_RESERVED;	/* avoid to swap out this VMA */

	pos = dev->frame[i].bufmem;
	while (size > 0) {	/* size is page-aligned */
		if (vm_insert_page(vma, start, vmalloc_to_page(pos))) {
			em28xx_videodbg("mmap: vm_insert_page failed\n");
			mutex_unlock(&dev->fileop_lock);
			return -EAGAIN;
		}
		start += PAGE_SIZE;
		pos += PAGE_SIZE;
		size -= PAGE_SIZE;
	}

	vma->vm_ops = &em28xx_vm_ops;
	vma->vm_private_data = &dev->frame[i];

	em28xx_vm_open(vma);
	mutex_unlock(&dev->fileop_lock);
	return 0;
}

/*
 * em28xx_get_ctrl()
 * return the current saturation, brightness or contrast, mute state
 */
static int em28xx_get_ctrl(struct em28xx *dev, struct v4l2_control *ctrl)
{
	switch (ctrl->id) {
	case V4L2_CID_AUDIO_MUTE:
		ctrl->value = dev->mute;
		return 0;
	case V4L2_CID_AUDIO_VOLUME:
		ctrl->value = dev->volume;
		return 0;
	default:
		return -EINVAL;
	}
}

/*
 * em28xx_set_ctrl()
 * mute or set new saturation, brightness or contrast
 */
static int em28xx_set_ctrl(struct em28xx *dev, const struct v4l2_control *ctrl)
{
	switch (ctrl->id) {
	case V4L2_CID_AUDIO_MUTE:
		if (ctrl->value != dev->mute) {
			dev->mute = ctrl->value;
			em28xx_audio_usb_mute(dev, ctrl->value);
			return em28xx_audio_analog_set(dev);
		}
		return 0;
	case V4L2_CID_AUDIO_VOLUME:
		dev->volume = ctrl->value;
		return em28xx_audio_analog_set(dev);
	default:
		return -EINVAL;
	}
}

/*
 * em28xx_stream_interrupt()
 * stops streaming
 */
static int em28xx_stream_interrupt(struct em28xx *dev)
{
	int ret = 0;

	/* stop reading from the device */

	dev->stream = STREAM_INTERRUPT;
	ret = wait_event_timeout(dev->wait_stream,
				 (dev->stream == STREAM_OFF) ||
				 (dev->state & DEV_DISCONNECTED),
				 EM28XX_URB_TIMEOUT);
	if (dev->state & DEV_DISCONNECTED)
		return -ENODEV;
	else if (ret) {
		dev->state |= DEV_MISCONFIGURED;
		em28xx_videodbg("device is misconfigured; close and "
			"open /dev/video%d again\n",
				dev->vdev->minor-MINOR_VFL_TYPE_GRABBER_MIN);
		return ret;
	}

	return 0;
}

static int em28xx_set_norm(struct em28xx *dev, int width, int height)
{
	unsigned int hscale, vscale;
	unsigned int maxh, maxw;

	maxw = norm_maxw(dev);
	maxh = norm_maxh(dev);

	/* width must even because of the YUYV format */
	/* height must be even because of interlacing */
	height &= 0xfffe;
	width &= 0xfffe;

	if (height < 32)
		height = 32;
	if (height > maxh)
		height = maxh;
	if (width < 48)
		width = 48;
	if (width > maxw)
		width = maxw;

	if ((hscale = (((unsigned long)maxw) << 12) / width - 4096L) >= 0x4000)
		hscale = 0x3fff;
	width = (((unsigned long)maxw) << 12) / (hscale + 4096L);

	if ((vscale = (((unsigned long)maxh) << 12) / height - 4096L) >= 0x4000)
		vscale = 0x3fff;
	height = (((unsigned long)maxh) << 12) / (vscale + 4096L);

	/* set new image size */
	dev->width = width;
	dev->height = height;
	dev->frame_size = dev->width * dev->height * 2;
	dev->field_size = dev->frame_size >> 1;	/*both_fileds ? dev->frame_size>>1 : dev->frame_size; */
	dev->bytesperline = dev->width * 2;
	dev->hscale = hscale;
	dev->vscale = vscale;

	em28xx_resolution_set(dev);

	return 0;
}

static int em28xx_get_fmt(struct em28xx *dev, struct v4l2_format *format)
{
	em28xx_videodbg("VIDIOC_G_FMT: type=%s\n",
		(format->type ==V4L2_BUF_TYPE_VIDEO_CAPTURE) ?
		"V4L2_BUF_TYPE_VIDEO_CAPTURE" :
		(format->type ==V4L2_BUF_TYPE_VBI_CAPTURE) ?
		"V4L2_BUF_TYPE_VBI_CAPTURE" :
		(format->type ==V4L2_CAP_SLICED_VBI_CAPTURE) ?
		"V4L2_BUF_TYPE_SLICED_VBI_CAPTURE " :
		"not supported");

	switch (format->type) {
	case V4L2_BUF_TYPE_VIDEO_CAPTURE:
	{
		format->fmt.pix.width = dev->width;
		format->fmt.pix.height = dev->height;
		format->fmt.pix.pixelformat = V4L2_PIX_FMT_YUYV;
		format->fmt.pix.bytesperline = dev->bytesperline;
		format->fmt.pix.sizeimage = dev->frame_size;
		format->fmt.pix.colorspace = V4L2_COLORSPACE_SMPTE170M;
		format->fmt.pix.field = dev->interlaced ? V4L2_FIELD_INTERLACED : V4L2_FIELD_TOP;	/* FIXME: TOP? NONE? BOTTOM? ALTENATE? */

		em28xx_videodbg("VIDIOC_G_FMT: %dx%d\n", dev->width,
			dev->height);
		break;
	}

	case V4L2_BUF_TYPE_SLICED_VBI_CAPTURE:
	{
		format->fmt.sliced.service_set=0;

		em28xx_i2c_call_clients(dev,VIDIOC_G_FMT,format);

		if (format->fmt.sliced.service_set==0)
			return -EINVAL;

		break;
	}

	default:
		return -EINVAL;
	}
	return (0);
}

static int em28xx_set_fmt(struct em28xx *dev, unsigned int cmd, struct v4l2_format *format)
{
	u32 i;
	int ret = 0;
	int width = format->fmt.pix.width;
	int height = format->fmt.pix.height;
	unsigned int hscale, vscale;
	unsigned int maxh, maxw;

	maxw = norm_maxw(dev);
	maxh = norm_maxh(dev);

	em28xx_videodbg("%s: type=%s\n",
			cmd == VIDIOC_TRY_FMT ?
			"VIDIOC_TRY_FMT" : "VIDIOC_S_FMT",
			format->type == V4L2_BUF_TYPE_VIDEO_CAPTURE ?
			"V4L2_BUF_TYPE_VIDEO_CAPTURE" :
			format->type == V4L2_BUF_TYPE_VBI_CAPTURE ?
			"V4L2_BUF_TYPE_VBI_CAPTURE " :
			"not supported");

	if (format->type == V4L2_BUF_TYPE_SLICED_VBI_CAPTURE) {
		em28xx_i2c_call_clients(dev,VIDIOC_G_FMT,format);

		if (format->fmt.sliced.service_set==0)
			return -EINVAL;

		return 0;
	}


	if (format->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
		return -EINVAL;

	em28xx_videodbg("%s: requested %dx%d\n",
		cmd == VIDIOC_TRY_FMT ?
		"VIDIOC_TRY_FMT" : "VIDIOC_S_FMT",
		format->fmt.pix.width, format->fmt.pix.height);

	/* FIXME: Move some code away from here */
	/* width must even because of the YUYV format */
	/* height must be even because of interlacing */
	height &= 0xfffe;
	width &= 0xfffe;

	if (height < 32)
		height = 32;
	if (height > maxh)
		height = maxh;
	if (width < 48)
		width = 48;
	if (width > maxw)
		width = maxw;

	if(dev->is_em2800){
		/* the em2800 can only scale down to 50% */
		if(height % (maxh / 2))
			height=maxh;
		if(width % (maxw / 2))
			width=maxw;
		/* according to empiatech support */
		/* the MaxPacketSize is to small to support */
		/* framesizes larger than 640x480 @ 30 fps */
		/* or 640x576 @ 25 fps. As this would cut */
		/* of a part of the image we prefer */
		/* 360x576 or 360x480 for now */
		if(width == maxw && height == maxh)
			width /= 2;
	}

	if ((hscale = (((unsigned long)maxw) << 12) / width - 4096L) >= 0x4000)
		hscale = 0x3fff;

	width = (((unsigned long)maxw) << 12) / (hscale + 4096L);

	if ((vscale = (((unsigned long)maxh) << 12) / height - 4096L) >= 0x4000)
		vscale = 0x3fff;

	height = (((unsigned long)maxh) << 12) / (vscale + 4096L);

	format->fmt.pix.width = width;
	format->fmt.pix.height = height;
	format->fmt.pix.pixelformat = V4L2_PIX_FMT_YUYV;
	format->fmt.pix.bytesperline = width * 2;
	format->fmt.pix.sizeimage = width * 2 * height;
	format->fmt.pix.colorspace = V4L2_COLORSPACE_SMPTE170M;
	format->fmt.pix.field = V4L2_FIELD_INTERLACED;

	em28xx_videodbg("%s: returned %dx%d (%d, %d)\n",
		cmd == VIDIOC_TRY_FMT ?
		"VIDIOC_TRY_FMT" :"VIDIOC_S_FMT",
		format->fmt.pix.width, format->fmt.pix.height, hscale, vscale);

	if (cmd == VIDIOC_TRY_FMT)
		return 0;

	for (i = 0; i < dev->num_frames; i++)
		if (dev->frame[i].vma_use_count) {
			em28xx_videodbg("VIDIOC_S_FMT failed. "
				"Unmap the buffers first.\n");
			return -EINVAL;
		}

	/* stop io in case it is already in progress */
	if (dev->stream == STREAM_ON) {
		em28xx_videodbg("VIDIOC_SET_FMT: interupting stream\n");
		if ((ret = em28xx_stream_interrupt(dev)))
			return ret;
	}

	em28xx_release_buffers(dev);
	dev->io = IO_NONE;

	/* set new image size */
	dev->width = width;
	dev->height = height;
	dev->frame_size = dev->width * dev->height * 2;
	dev->field_size = dev->frame_size >> 1;
	dev->bytesperline = dev->width * 2;
	dev->hscale = hscale;
	dev->vscale = vscale;
	em28xx_uninit_isoc(dev);
	em28xx_set_alternate(dev);
	em28xx_capture_start(dev, 1);
	em28xx_resolution_set(dev);
	em28xx_init_isoc(dev);

	return 0;
}

/*
 * em28xx_v4l2_do_ioctl()
 * This function is _not_ called directly, but from
 * em28xx_v4l2_ioctl. Userspace
 * copying is done already, arg is a kernel pointer.
 */
static int em28xx_do_ioctl(struct inode *inode, struct file *filp,
			   struct em28xx *dev, unsigned int cmd, void *arg,
			   v4l2_kioctl driver_ioctl)
{
	int ret;

	switch (cmd) {
		/* ---------- tv norms ---------- */
	case VIDIOC_ENUMSTD:
	{