uvc_v4l2.c

linux camera下的uvc driver驱动源码

		uvc_ctrl_begin(video);
		for (i = 0; i < ctrls->count; ++ctrl, ++i) {
			ret = uvc_ctrl_get(video, ctrl);
			if (ret < 0) {
				uvc_ctrl_rollback(video);
				ctrls->error_idx = i;
				return ret;
			}
		}
		ctrls->error_idx = 0;
		ret = uvc_ctrl_rollback(video);
	}
		break;

	case VIDIOC_S_EXT_CTRLS:
	case VIDIOC_TRY_EXT_CTRLS:
	{
		struct v4l2_ext_controls *ctrls = (struct v4l2_ext_controls*)arg;
		struct v4l2_ext_control *ctrl = ctrls->controls;
		unsigned int i;

		ret = uvc_ctrl_begin(video);
		if (ret < 0)
			return ret;

		for (i = 0; i < ctrls->count; ++ctrl, ++i) {
			ret = uvc_ctrl_set(video, ctrl);
			if (ret < 0) {
				uvc_ctrl_rollback(video);
				ctrls->error_idx = i;
				return ret;
			}
		}

		ctrls->error_idx = 0;

		if (cmd == VIDIOC_S_EXT_CTRLS)
			ret = uvc_ctrl_commit(video);
		else
			ret = uvc_ctrl_rollback(video);
	}
		break;

	/* Get, Set & Enum input */
	case VIDIOC_ENUMINPUT:
	{
		const struct uvc_entity *selector = video->selector;
		struct v4l2_input *input = arg;
		struct uvc_entity *iterm = NULL;
		u32 index = input->index;
		int pin = 0;

		if (selector == NULL) {
			if (index != 0)
				return -EINVAL;
			iterm = list_first_entry(&video->iterms,
					struct uvc_entity, chain);
			pin = iterm->id;
		} else if (pin < selector->selector.bNrInPins) {
			pin = selector->selector.baSourceID[index];
			list_for_each_entry(iterm, video->iterms.next, chain) {
				if (iterm->id == pin)
					break;
			}
		}

		if (iterm == NULL || iterm->id != pin)
			return -EINVAL;

		memset(input, 0, sizeof *input);
		input->index = index;
		strncpy(input->name, iterm->name, sizeof input->name);
		if (UVC_ENTITY_TYPE(iterm) == ITT_CAMERA)
			input->type = V4L2_INPUT_TYPE_CAMERA;
	}
		break;

	case VIDIOC_G_INPUT:
	{
		u8 input;

		if (video->selector == NULL) {
			*(int*)arg = 0;
			break;
		}

		ret = uvc_query_ctrl(video->dev, GET_CUR, video->selector->id,
			video->dev->intfnum, SU_INPUT_SELECT_CONTROL,
			&input, 1);
		if (ret < 0)
			return ret;

		*(int*)arg = input - 1;
	}
		break;

	case VIDIOC_S_INPUT:
	{
		u8 input = *(u32*)arg + 1;

		if ((ret = uvc_acquire_privileges(handle)) < 0)
			return ret;

		if (video->selector == NULL) {
			if (input != 1)
				return -EINVAL;
			break;
		}

		if (input > video->selector->selector.bNrInPins)
			return -EINVAL;

		return uvc_query_ctrl(video->dev, SET_CUR, video->selector->id,
			video->dev->intfnum, SU_INPUT_SELECT_CONTROL,
			&input, 1);
	}

	/* Try, Get, Set & Enum format */
	case VIDIOC_ENUM_FMT:
	{
		struct v4l2_fmtdesc *fmt = arg;
		struct uvc_format *format;

		if (fmt->type != V4L2_BUF_TYPE_VIDEO_CAPTURE ||
		    fmt->index >= video->streaming->nformats)
			return -EINVAL;

		format = &video->streaming->format[fmt->index];
		fmt->flags = 0;
		if (format->flags & UVC_FMT_FLAG_COMPRESSED)
			fmt->flags |= V4L2_FMT_FLAG_COMPRESSED;
		strncpy(fmt->description, format->name,
			sizeof fmt->description);
		fmt->description[sizeof fmt->description - 1] = 0;
		fmt->pixelformat = format->fcc;

	}
		break;

	case VIDIOC_TRY_FMT:
	{
		struct uvc_streaming_control probe;

		if ((ret = uvc_acquire_privileges(handle)) < 0)
			return ret;

		return uvc_v4l2_try_format(video, (struct v4l2_format*)arg,
						&probe, NULL, NULL);
	}

	case VIDIOC_S_FMT:
		if ((ret = uvc_acquire_privileges(handle)) < 0)
			return ret;

		return uvc_v4l2_set_format(video, (struct v4l2_format*)arg);

	case VIDIOC_G_FMT:
		return uvc_v4l2_get_format(video, (struct v4l2_format*)arg);

	/* Frame size enumeration */
	case VIDIOC_ENUM_FRAMESIZES:
	{
		struct v4l2_frmsizeenum *fsize = arg;
		struct uvc_format *format = NULL;
		struct uvc_frame *frame;
		int i;

		/* Look for the given pixel format */
		for (i = 0; i < video->streaming->nformats; i++) {
			if (video->streaming->format[i].fcc == fsize->pixel_format) {
				format = &video->streaming->format[i];
				break;
			}
		}
		if (format == NULL)
			return -EINVAL;

		if (fsize->index >= format->nframes)
			return -EINVAL;

		frame = &format->frame[fsize->index];
		fsize->type = V4L2_FRMSIZE_TYPE_DISCRETE;
		fsize->discrete.width = frame->wWidth;
		fsize->discrete.height = frame->wHeight;
	}
		break;

	/* Frame interval enumeration */
	case VIDIOC_ENUM_FRAMEINTERVALS:
	{
		struct v4l2_frmivalenum *fival = arg;
		struct uvc_format *format;
		struct uvc_frame *frame = NULL;
		int i, j;

		/* Look for the given pixel format and frame size */
		for (i = 0; i < video->streaming->nformats; i++) {
			if (video->streaming->format[i].fcc == fival->pixel_format) {
				format = &video->streaming->format[i];
				for (j = 0; j < format->nframes; j++) {
					if (format->frame[j].wWidth == fival->width &&
					    format->frame[j].wHeight == fival->height) {
						frame = &format->frame[j];
						break;
					}
				}
				break;	/* Each format should occur only once. */
			}
		}
		if (frame == NULL)
			return -EINVAL;

		if (frame->bFrameIntervalType) {
			if (fival->index >= frame->bFrameIntervalType)
				return -EINVAL;

			fival->type = V4L2_FRMIVAL_TYPE_DISCRETE;
			fival->discrete.numerator = frame->dwFrameInterval[fival->index];
			fival->discrete.denominator = 10000000;
			uvc_simplify_fraction(&fival->discrete.numerator,
					&fival->discrete.denominator, 8, 333);
		} else {
			fival->type = V4L2_FRMIVAL_TYPE_STEPWISE;
			fival->stepwise.min.numerator = frame->dwFrameInterval[0];
			fival->stepwise.min.denominator = 10000000;
			fival->stepwise.max.numerator = frame->dwFrameInterval[1];
			fival->stepwise.max.denominator = 10000000;
			fival->stepwise.step.numerator = frame->dwFrameInterval[2];
			fival->stepwise.step.denominator = 10000000;
			uvc_simplify_fraction(&fival->stepwise.min.numerator,
					&fival->stepwise.min.denominator, 8, 333);
			uvc_simplify_fraction(&fival->stepwise.max.numerator,
					&fival->stepwise.max.denominator, 8, 333);
			uvc_simplify_fraction(&fival->stepwise.step.numerator,
					&fival->stepwise.step.denominator, 8, 333);
		}
	}
		break;

	/* Get & Set streaming parameters */
	case VIDIOC_G_PARM:
		return uvc_v4l2_get_streamparm(video, (struct v4l2_streamparm*)arg);

	case VIDIOC_S_PARM:
		if ((ret = uvc_acquire_privileges(handle)) < 0)
			return ret;

		return uvc_v4l2_set_streamparm(video, (struct v4l2_streamparm*)arg);

	/* Cropping and scaling */
	case VIDIOC_CROPCAP:
	{
		struct v4l2_cropcap *ccap = arg;
		struct uvc_frame *frame = video->streaming->cur_frame;

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

		ccap->bounds.left = 0;
		ccap->bounds.top = 0;
		ccap->bounds.width = frame->wWidth;
		ccap->bounds.height = frame->wHeight;

		ccap->defrect = ccap->bounds;

		ccap->pixelaspect.numerator = 1;
		ccap->pixelaspect.denominator = 1;
	}
		break;

	case VIDIOC_G_CROP:
	case VIDIOC_S_CROP:
		return -EINVAL;

	/* Buffers & streaming */
	case VIDIOC_REQBUFS:
	{
		struct v4l2_requestbuffers *rb = arg;
		unsigned int bufsize = video->streaming->ctrl.dwMaxVideoFrameSize;

		if (rb->type != V4L2_BUF_TYPE_VIDEO_CAPTURE ||
		    rb->memory != V4L2_MEMORY_MMAP)
			return -EINVAL;

		if ((ret = uvc_acquire_privileges(handle)) < 0)
			return ret;

		if ((ret = uvc_alloc_buffers(&video->queue, rb->count, bufsize)) < 0)
			return ret;

		rb->count = ret;
		ret = 0;
	}
		break;

	case VIDIOC_QUERYBUF:
	{
		struct v4l2_buffer *buf = arg;

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

		if (!uvc_has_privileges(handle))
			return -EBUSY;

		return uvc_query_buffer(&video->queue, buf);
	}

	case VIDIOC_QBUF:
		if (!uvc_has_privileges(handle))
			return -EBUSY;

		return uvc_queue_buffer(&video->queue,
			(struct v4l2_buffer*)arg);

	case VIDIOC_DQBUF:
		if (!uvc_has_privileges(handle))
			return -EBUSY;

		return uvc_dequeue_buffer(&video->queue,
			(struct v4l2_buffer*)arg, file->f_flags & O_NONBLOCK);

	case VIDIOC_STREAMON:
	{
		int *type = arg;

		if (*type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
			return -EINVAL;

		if (!uvc_has_privileges(handle))
			return -EBUSY;

		if ((ret = uvc_video_enable(video, 1)) < 0)
			return ret;
	}
		break;

	case VIDIOC_STREAMOFF:
	{
		int *type = arg;

		if (*type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
			return -EINVAL;

		if (!uvc_has_privileges(handle))
			return -EBUSY;

		return uvc_video_enable(video, 0);
	}

	/* Analog video standards make no sense for digital cameras. */
	case VIDIOC_ENUMSTD:
	case VIDIOC_QUERYSTD:
	case VIDIOC_G_STD:
	case VIDIOC_S_STD:

	case VIDIOC_OVERLAY:

	case VIDIOC_ENUMAUDIO:
	case VIDIOC_ENUMAUDOUT:

	case VIDIOC_ENUMOUTPUT:
		uvc_trace(UVC_TRACE_IOCTL, "Unsupported ioctl 0x%08x\n", cmd);
		return -EINVAL;

	/* Dynamic controls. */
	case UVCIOC_CTRL_ADD:
	{
		struct uvc_xu_control_info *xinfo = arg;
		struct uvc_control_info *info;

		info = kmalloc(sizeof *info, GFP_KERNEL);
		if (info == NULL)
			return -ENOMEM;

		memcpy(info->entity, xinfo->entity, sizeof info->entity);
		info->index = xinfo->index;
		info->selector = xinfo->selector;
		info->size = xinfo->size;
		info->flags = xinfo->flags;

		info->flags |= UVC_CONTROL_GET_MIN | UVC_CONTROL_GET_MAX |
				UVC_CONTROL_GET_RES | UVC_CONTROL_GET_DEF;

		ret = uvc_ctrl_add_info(info);
		if (ret < 0)
			kfree(info);
	}
		break;

	case UVCIOC_CTRL_MAP:
	{
		struct uvc_xu_control_mapping *xmap = arg;
		struct uvc_control_mapping *map;

		map = kmalloc(sizeof *map, GFP_KERNEL);
		if (map == NULL)
			return -ENOMEM;

		map->id = xmap->id;
		memcpy(map->name, xmap->name, sizeof map->name);
		memcpy(map->entity, xmap->entity, sizeof map->entity);
		map->selector = xmap->selector;
		map->size = xmap->size;
		map->offset = xmap->offset;
		map->v4l2_type = xmap->v4l2_type;
		map->data_type = xmap->data_type;

		ret = uvc_ctrl_add_mapping(map);
		if (ret < 0)
			kfree(map);
	}
		break;

	case UVCIOC_CTRL_GET:
		return uvc_xu_ctrl_query(video, (struct uvc_xu_control*)arg, 0);

	case UVCIOC_CTRL_SET:
		return uvc_xu_ctrl_query(video, (struct uvc_xu_control*)arg, 1);

	default:
		if ((ret = v4l_compat_translate_ioctl(inode, file, cmd, arg,
			uvc_v4l2_do_ioctl)) == -ENOIOCTLCMD)
			uvc_trace(UVC_TRACE_IOCTL, "Unknown ioctl 0x%08x\n", cmd);
		return ret;
	}

	return ret;
}

static int uvc_v4l2_ioctl(struct inode *inode, struct file *file,
		     unsigned int cmd, unsigned long arg)
{
	uvc_trace(UVC_TRACE_CALLS, "uvc_v4l2_ioctl\n");
	return video_usercopy(inode, file, cmd, arg, uvc_v4l2_do_ioctl);
}

static ssize_t uvc_v4l2_read(struct file *file, char __user *data,
		    size_t count, loff_t *ppos)
{
	uvc_trace(UVC_TRACE_CALLS, "uvc_v4l2_read: not implemented.\n");
	return -ENODEV;
}

/*
 * VMA operations.
 */
static void uvc_vm_open(struct vm_area_struct *vma)
{
	struct uvc_buffer *buffer = vma->vm_private_data;
	buffer->vma_use_count++;
}

static void uvc_vm_close(struct vm_area_struct *vma)
{
	struct uvc_buffer *buffer = vma->vm_private_data;
	buffer->vma_use_count--;
}

static struct vm_operations_struct uvc_vm_ops = {
	.open		= uvc_vm_open,
	.close		= uvc_vm_close,
};

static int uvc_v4l2_mmap(struct file *file, struct vm_area_struct *vma)
{
	struct video_device *vdev = video_devdata(file);
	struct uvc_video_device *video = video_get_drvdata(vdev);
	struct uvc_buffer *buffer = NULL;
	struct page *page;
	unsigned long addr, start, size;
	unsigned int i;
	int ret = 0;

	uvc_trace(UVC_TRACE_CALLS, "uvc_v4l2_mmap\n");

	start = vma->vm_start;
	size = vma->vm_end - vma->vm_start;

	mutex_lock(&video->queue.mutex);

	for (i = 0; i < video->queue.count; ++i) {
		if ((video->queue.buffer[i].buf.m.offset >> PAGE_SHIFT) == vma->vm_pgoff) {
			buffer = &video->queue.buffer[i];
			break;
		}
	}

	if (buffer == NULL || size != video->queue.buf_size) {
		ret = -EINVAL;
		goto done;
	}

	/*
	 * VM_IO marks the area as being an mmaped region for I/O to a
	 * device. It also prevents the region from being core dumped.
	 */
	vma->vm_flags |= VM_IO;

	addr = (unsigned long)video->queue.mem + buffer->buf.m.offset;
	while (size > 0) {
		page = vmalloc_to_page((void*)addr);
		if ((ret = vm_insert_page(vma, start, page)) < 0)
			goto done;

		start += PAGE_SIZE;
		addr += PAGE_SIZE;
		size -= PAGE_SIZE;
	}

	vma->vm_ops = &uvc_vm_ops;
	vma->vm_private_data = buffer;
	uvc_vm_open(vma);

done:
	mutex_unlock(&video->queue.mutex);
	return ret;
}

static unsigned int uvc_v4l2_poll(struct file *file, poll_table *wait)
{
	struct video_device *vdev = video_devdata(file);
	struct uvc_video_device *video = video_get_drvdata(vdev);

	uvc_trace(UVC_TRACE_CALLS, "uvc_v4l2_poll\n");

	return uvc_queue_poll(&video->queue, file, wait);
}

struct file_operations uvc_fops = {
	.owner		= THIS_MODULE,
	.open		= uvc_v4l2_open,
	.release	= uvc_v4l2_release,
	.ioctl		= uvc_v4l2_ioctl,
#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,15)
	.compat_ioctl	= v4l_compat_ioctl32,
#endif
	.llseek		= no_llseek,
	.read		= uvc_v4l2_read,
	.mmap		= uvc_v4l2_mmap,
	.poll		= uvc_v4l2_poll,
};