path: root/drivers/media/video/uvc/uvc_video.c

/*
 *      uvc_video.c  --  USB Video Class driver - Video handling
 *
 *      Copyright (C) 2005-2008
 *          Laurent Pinchart (laurent.pinchart@skynet.be)
 *
 *      This program is free software; you can redistribute it and/or modify
 *      it under the terms of the GNU General Public License as published by
 *      the Free Software Foundation; either version 2 of the License, or
 *      (at your option) any later version.
 *
 */

#include <linux/kernel.h>
#include <linux/version.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/usb.h>
#include <linux/videodev2.h>
#include <linux/vmalloc.h>
#include <linux/wait.h>
#include <asm/atomic.h>
#include <asm/unaligned.h>

#include <media/v4l2-common.h>

#include "uvcvideo.h"

/* ------------------------------------------------------------------------
 * UVC Controls
 */

static int __uvc_query_ctrl(struct uvc_device *dev, __u8 query, __u8 unit,
			__u8 intfnum, __u8 cs, void *data, __u16 size,
			int timeout)
{
	__u8 type = USB_TYPE_CLASS | USB_RECIP_INTERFACE;
	unsigned int pipe;
	int ret;

	pipe = (query & 0x80) ? usb_rcvctrlpipe(dev->udev, 0)
			      : usb_sndctrlpipe(dev->udev, 0);
	type |= (query & 0x80) ? USB_DIR_IN : USB_DIR_OUT;

	ret = usb_control_msg(dev->udev, pipe, query, type, cs << 8,
			unit << 8 | intfnum, data, size, timeout);

	if (ret != size) {
		uvc_printk(KERN_ERR, "Failed to query (%u) UVC control %u "
			"(unit %u) : %d (exp. %u).\n", query, cs, unit, ret,
			size);
		return -EIO;
	}

	return 0;
}

int uvc_query_ctrl(struct uvc_device *dev, __u8 query, __u8 unit,
			__u8 intfnum, __u8 cs, void *data, __u16 size)
{
	return __uvc_query_ctrl(dev, query, unit, intfnum, cs, data, size,
				UVC_CTRL_CONTROL_TIMEOUT);
}

static void uvc_fixup_buffer_size(struct uvc_video_device *video,
	struct uvc_streaming_control *ctrl)
{
	struct uvc_format *format;
	struct uvc_frame *frame;

	if (ctrl->bFormatIndex <= 0 ||
	    ctrl->bFormatIndex > video->streaming->nformats)
		return;

	format = &video->streaming->format[ctrl->bFormatIndex - 1];

	if (ctrl->bFrameIndex <= 0 ||
	    ctrl->bFrameIndex > format->nframes)
		return;

	frame = &format->frame[ctrl->bFrameIndex - 1];

	if (!(format->flags & UVC_FMT_FLAG_COMPRESSED) ||
	     (ctrl->dwMaxVideoFrameSize == 0 &&
	      video->dev->uvc_version < 0x0110))
		ctrl->dwMaxVideoFrameSize =
			frame->dwMaxVideoFrameBufferSize;
}

static int uvc_get_video_ctrl(struct uvc_video_device *video,
	struct uvc_streaming_control *ctrl, int probe, __u8 query)
{
	__u8 *data;
	__u16 size;
	int ret;

	size = video->dev->uvc_version >= 0x0110 ? 34 : 26;
	data = kmalloc(size, GFP_KERNEL);
	if (data == NULL)
		return -ENOMEM;

	ret = __uvc_query_ctrl(video->dev, query, 0, video->streaming->intfnum,
		probe ? VS_PROBE_CONTROL : VS_COMMIT_CONTROL, data, size,
		UVC_CTRL_STREAMING_TIMEOUT);
	if (ret < 0)
		goto out;

	ctrl->bmHint = le16_to_cpup((__le16 *)&data[0]);
	ctrl->bFormatIndex = data[2];
	ctrl->bFrameIndex = data[3];
	ctrl->dwFrameInterval = le32_to_cpup((__le32 *)&data[4]);
	ctrl->wKeyFrameRate = le16_to_cpup((__le16 *)&data[8]);
	ctrl->wPFrameRate = le16_to_cpup((__le16 *)&data[10]);
	ctrl->wCompQuality = le16_to_cpup((__le16 *)&data[12]);
	ctrl->wCompWindowSize = le16_to_cpup((__le16 *)&data[14]);
	ctrl->wDelay = le16_to_cpup((__le16 *)&data[16]);
	ctrl->dwMaxVideoFrameSize =
		le32_to_cpu(get_unaligned((