forked from Minki/linux
66847ef013
UVC devices transmit a device timestamp along with video frames. Convert the timestamp to a host timestamp and use it to fill the V4L2 buffer timestamp field. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
1840 lines
53 KiB
C
1840 lines
53 KiB
C
/*
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* uvc_video.c -- USB Video Class driver - Video handling
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*
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* Copyright (C) 2005-2010
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* Laurent Pinchart (laurent.pinchart@ideasonboard.com)
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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*/
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#include <linux/kernel.h>
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#include <linux/list.h>
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#include <linux/module.h>
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#include <linux/slab.h>
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#include <linux/usb.h>
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#include <linux/videodev2.h>
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#include <linux/vmalloc.h>
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#include <linux/wait.h>
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#include <linux/atomic.h>
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#include <asm/unaligned.h>
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#include <media/v4l2-common.h>
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#include "uvcvideo.h"
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/* ------------------------------------------------------------------------
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* UVC Controls
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*/
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static int __uvc_query_ctrl(struct uvc_device *dev, __u8 query, __u8 unit,
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__u8 intfnum, __u8 cs, void *data, __u16 size,
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int timeout)
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{
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__u8 type = USB_TYPE_CLASS | USB_RECIP_INTERFACE;
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unsigned int pipe;
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pipe = (query & 0x80) ? usb_rcvctrlpipe(dev->udev, 0)
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: usb_sndctrlpipe(dev->udev, 0);
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type |= (query & 0x80) ? USB_DIR_IN : USB_DIR_OUT;
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return usb_control_msg(dev->udev, pipe, query, type, cs << 8,
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unit << 8 | intfnum, data, size, timeout);
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}
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static const char *uvc_query_name(__u8 query)
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{
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switch (query) {
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case UVC_SET_CUR:
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return "SET_CUR";
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case UVC_GET_CUR:
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return "GET_CUR";
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case UVC_GET_MIN:
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return "GET_MIN";
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case UVC_GET_MAX:
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return "GET_MAX";
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case UVC_GET_RES:
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return "GET_RES";
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case UVC_GET_LEN:
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return "GET_LEN";
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case UVC_GET_INFO:
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return "GET_INFO";
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case UVC_GET_DEF:
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return "GET_DEF";
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default:
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return "<invalid>";
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}
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}
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int uvc_query_ctrl(struct uvc_device *dev, __u8 query, __u8 unit,
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__u8 intfnum, __u8 cs, void *data, __u16 size)
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{
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int ret;
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ret = __uvc_query_ctrl(dev, query, unit, intfnum, cs, data, size,
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UVC_CTRL_CONTROL_TIMEOUT);
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if (ret != size) {
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uvc_printk(KERN_ERR, "Failed to query (%s) UVC control %u on "
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"unit %u: %d (exp. %u).\n", uvc_query_name(query), cs,
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unit, ret, size);
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return -EIO;
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}
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return 0;
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}
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static void uvc_fixup_video_ctrl(struct uvc_streaming *stream,
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struct uvc_streaming_control *ctrl)
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{
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struct uvc_format *format = NULL;
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struct uvc_frame *frame = NULL;
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unsigned int i;
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for (i = 0; i < stream->nformats; ++i) {
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if (stream->format[i].index == ctrl->bFormatIndex) {
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format = &stream->format[i];
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break;
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}
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}
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if (format == NULL)
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return;
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for (i = 0; i < format->nframes; ++i) {
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if (format->frame[i].bFrameIndex == ctrl->bFrameIndex) {
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frame = &format->frame[i];
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break;
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}
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}
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if (frame == NULL)
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return;
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if (!(format->flags & UVC_FMT_FLAG_COMPRESSED) ||
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(ctrl->dwMaxVideoFrameSize == 0 &&
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stream->dev->uvc_version < 0x0110))
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ctrl->dwMaxVideoFrameSize =
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frame->dwMaxVideoFrameBufferSize;
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if (!(format->flags & UVC_FMT_FLAG_COMPRESSED) &&
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stream->dev->quirks & UVC_QUIRK_FIX_BANDWIDTH &&
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stream->intf->num_altsetting > 1) {
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u32 interval;
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u32 bandwidth;
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interval = (ctrl->dwFrameInterval > 100000)
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? ctrl->dwFrameInterval
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: frame->dwFrameInterval[0];
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/* Compute a bandwidth estimation by multiplying the frame
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* size by the number of video frames per second, divide the
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* result by the number of USB frames (or micro-frames for
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* high-speed devices) per second and add the UVC header size
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* (assumed to be 12 bytes long).
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*/
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bandwidth = frame->wWidth * frame->wHeight / 8 * format->bpp;
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bandwidth *= 10000000 / interval + 1;
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bandwidth /= 1000;
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if (stream->dev->udev->speed == USB_SPEED_HIGH)
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bandwidth /= 8;
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bandwidth += 12;
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/* The bandwidth estimate is too low for many cameras. Don't use
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* maximum packet sizes lower than 1024 bytes to try and work
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* around the problem. According to measurements done on two
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* different camera models, the value is high enough to get most
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* resolutions working while not preventing two simultaneous
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* VGA streams at 15 fps.
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*/
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bandwidth = max_t(u32, bandwidth, 1024);
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ctrl->dwMaxPayloadTransferSize = bandwidth;
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}
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}
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static int uvc_get_video_ctrl(struct uvc_streaming *stream,
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struct uvc_streaming_control *ctrl, int probe, __u8 query)
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{
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__u8 *data;
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__u16 size;
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int ret;
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size = stream->dev->uvc_version >= 0x0110 ? 34 : 26;
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if ((stream->dev->quirks & UVC_QUIRK_PROBE_DEF) &&
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query == UVC_GET_DEF)
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return -EIO;
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data = kmalloc(size, GFP_KERNEL);
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if (data == NULL)
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return -ENOMEM;
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ret = __uvc_query_ctrl(stream->dev, query, 0, stream->intfnum,
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probe ? UVC_VS_PROBE_CONTROL : UVC_VS_COMMIT_CONTROL, data,
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size, uvc_timeout_param);
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if ((query == UVC_GET_MIN || query == UVC_GET_MAX) && ret == 2) {
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/* Some cameras, mostly based on Bison Electronics chipsets,
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* answer a GET_MIN or GET_MAX request with the wCompQuality
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* field only.
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*/
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uvc_warn_once(stream->dev, UVC_WARN_MINMAX, "UVC non "
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"compliance - GET_MIN/MAX(PROBE) incorrectly "
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"supported. Enabling workaround.\n");
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memset(ctrl, 0, sizeof *ctrl);
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ctrl->wCompQuality = le16_to_cpup((__le16 *)data);
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ret = 0;
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goto out;
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} else if (query == UVC_GET_DEF && probe == 1 && ret != size) {
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/* Many cameras don't support the GET_DEF request on their
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* video probe control. Warn once and return, the caller will
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* fall back to GET_CUR.
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*/
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uvc_warn_once(stream->dev, UVC_WARN_PROBE_DEF, "UVC non "
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"compliance - GET_DEF(PROBE) not supported. "
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"Enabling workaround.\n");
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ret = -EIO;
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goto out;
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} else if (ret != size) {
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uvc_printk(KERN_ERR, "Failed to query (%u) UVC %s control : "
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"%d (exp. %u).\n", query, probe ? "probe" : "commit",
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ret, size);
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ret = -EIO;
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goto out;
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}
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ctrl->bmHint = le16_to_cpup((__le16 *)&data[0]);
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ctrl->bFormatIndex = data[2];
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ctrl->bFrameIndex = data[3];
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ctrl->dwFrameInterval = le32_to_cpup((__le32 *)&data[4]);
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ctrl->wKeyFrameRate = le16_to_cpup((__le16 *)&data[8]);
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ctrl->wPFrameRate = le16_to_cpup((__le16 *)&data[10]);
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ctrl->wCompQuality = le16_to_cpup((__le16 *)&data[12]);
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ctrl->wCompWindowSize = le16_to_cpup((__le16 *)&data[14]);
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ctrl->wDelay = le16_to_cpup((__le16 *)&data[16]);
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ctrl->dwMaxVideoFrameSize = get_unaligned_le32(&data[18]);
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ctrl->dwMaxPayloadTransferSize = get_unaligned_le32(&data[22]);
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if (size == 34) {
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ctrl->dwClockFrequency = get_unaligned_le32(&data[26]);
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ctrl->bmFramingInfo = data[30];
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ctrl->bPreferedVersion = data[31];
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ctrl->bMinVersion = data[32];
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ctrl->bMaxVersion = data[33];
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} else {
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ctrl->dwClockFrequency = stream->dev->clock_frequency;
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ctrl->bmFramingInfo = 0;
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ctrl->bPreferedVersion = 0;
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ctrl->bMinVersion = 0;
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ctrl->bMaxVersion = 0;
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}
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/* Some broken devices return null or wrong dwMaxVideoFrameSize and
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* dwMaxPayloadTransferSize fields. Try to get the value from the
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* format and frame descriptors.
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*/
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uvc_fixup_video_ctrl(stream, ctrl);
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ret = 0;
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out:
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kfree(data);
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return ret;
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}
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static int uvc_set_video_ctrl(struct uvc_streaming *stream,
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struct uvc_streaming_control *ctrl, int probe)
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{
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__u8 *data;
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__u16 size;
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int ret;
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size = stream->dev->uvc_version >= 0x0110 ? 34 : 26;
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data = kzalloc(size, GFP_KERNEL);
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if (data == NULL)
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return -ENOMEM;
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*(__le16 *)&data[0] = cpu_to_le16(ctrl->bmHint);
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data[2] = ctrl->bFormatIndex;
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data[3] = ctrl->bFrameIndex;
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*(__le32 *)&data[4] = cpu_to_le32(ctrl->dwFrameInterval);
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*(__le16 *)&data[8] = cpu_to_le16(ctrl->wKeyFrameRate);
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*(__le16 *)&data[10] = cpu_to_le16(ctrl->wPFrameRate);
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*(__le16 *)&data[12] = cpu_to_le16(ctrl->wCompQuality);
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*(__le16 *)&data[14] = cpu_to_le16(ctrl->wCompWindowSize);
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*(__le16 *)&data[16] = cpu_to_le16(ctrl->wDelay);
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put_unaligned_le32(ctrl->dwMaxVideoFrameSize, &data[18]);
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put_unaligned_le32(ctrl->dwMaxPayloadTransferSize, &data[22]);
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if (size == 34) {
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put_unaligned_le32(ctrl->dwClockFrequency, &data[26]);
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data[30] = ctrl->bmFramingInfo;
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data[31] = ctrl->bPreferedVersion;
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data[32] = ctrl->bMinVersion;
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data[33] = ctrl->bMaxVersion;
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}
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ret = __uvc_query_ctrl(stream->dev, UVC_SET_CUR, 0, stream->intfnum,
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probe ? UVC_VS_PROBE_CONTROL : UVC_VS_COMMIT_CONTROL, data,
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size, uvc_timeout_param);
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if (ret != size) {
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uvc_printk(KERN_ERR, "Failed to set UVC %s control : "
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"%d (exp. %u).\n", probe ? "probe" : "commit",
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ret, size);
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ret = -EIO;
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}
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kfree(data);
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return ret;
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}
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int uvc_probe_video(struct uvc_streaming *stream,
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struct uvc_streaming_control *probe)
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{
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struct uvc_streaming_control probe_min, probe_max;
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__u16 bandwidth;
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unsigned int i;
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int ret;
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/* Perform probing. The device should adjust the requested values
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* according to its capabilities. However, some devices, namely the
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* first generation UVC Logitech webcams, don't implement the Video
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* Probe control properly, and just return the needed bandwidth. For
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* that reason, if the needed bandwidth exceeds the maximum available
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* bandwidth, try to lower the quality.
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*/
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ret = uvc_set_video_ctrl(stream, probe, 1);
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if (ret < 0)
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goto done;
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/* Get the minimum and maximum values for compression settings. */
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if (!(stream->dev->quirks & UVC_QUIRK_PROBE_MINMAX)) {
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ret = uvc_get_video_ctrl(stream, &probe_min, 1, UVC_GET_MIN);
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if (ret < 0)
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goto done;
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ret = uvc_get_video_ctrl(stream, &probe_max, 1, UVC_GET_MAX);
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if (ret < 0)
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goto done;
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probe->wCompQuality = probe_max.wCompQuality;
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}
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for (i = 0; i < 2; ++i) {
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ret = uvc_set_video_ctrl(stream, probe, 1);
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if (ret < 0)
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goto done;
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ret = uvc_get_video_ctrl(stream, probe, 1, UVC_GET_CUR);
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if (ret < 0)
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goto done;
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if (stream->intf->num_altsetting == 1)
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break;
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bandwidth = probe->dwMaxPayloadTransferSize;
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if (bandwidth <= stream->maxpsize)
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break;
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if (stream->dev->quirks & UVC_QUIRK_PROBE_MINMAX) {
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ret = -ENOSPC;
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goto done;
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}
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/* TODO: negotiate compression parameters */
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probe->wKeyFrameRate = probe_min.wKeyFrameRate;
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probe->wPFrameRate = probe_min.wPFrameRate;
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probe->wCompQuality = probe_max.wCompQuality;
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probe->wCompWindowSize = probe_min.wCompWindowSize;
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}
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done:
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return ret;
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}
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static int uvc_commit_video(struct uvc_streaming *stream,
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struct uvc_streaming_control *probe)
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{
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return uvc_set_video_ctrl(stream, probe, 0);
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}
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/* -----------------------------------------------------------------------------
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* Clocks and timestamps
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*/
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static void
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uvc_video_clock_decode(struct uvc_streaming *stream, struct uvc_buffer *buf,
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const __u8 *data, int len)
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{
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struct uvc_clock_sample *sample;
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unsigned int header_size;
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bool has_pts = false;
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bool has_scr = false;
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unsigned long flags;
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struct timespec ts;
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u16 host_sof;
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u16 dev_sof;
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switch (data[1] & (UVC_STREAM_PTS | UVC_STREAM_SCR)) {
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case UVC_STREAM_PTS | UVC_STREAM_SCR:
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header_size = 12;
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has_pts = true;
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has_scr = true;
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break;
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case UVC_STREAM_PTS:
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header_size = 6;
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has_pts = true;
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break;
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case UVC_STREAM_SCR:
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header_size = 8;
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has_scr = true;
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break;
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default:
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header_size = 2;
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break;
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}
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/* Check for invalid headers. */
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if (len < header_size)
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return;
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/* Extract the timestamps:
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*
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* - store the frame PTS in the buffer structure
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* - if the SCR field is present, retrieve the host SOF counter and
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* kernel timestamps and store them with the SCR STC and SOF fields
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* in the ring buffer
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*/
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if (has_pts && buf != NULL)
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buf->pts = get_unaligned_le32(&data[2]);
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if (!has_scr)
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return;
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/* To limit the amount of data, drop SCRs with an SOF identical to the
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* previous one.
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*/
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dev_sof = get_unaligned_le16(&data[header_size - 2]);
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if (dev_sof == stream->clock.last_sof)
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return;
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stream->clock.last_sof = dev_sof;
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host_sof = usb_get_current_frame_number(stream->dev->udev);
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ktime_get_ts(&ts);
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|
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/* The UVC specification allows device implementations that can't obtain
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* the USB frame number to keep their own frame counters as long as they
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* match the size and frequency of the frame number associated with USB
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* SOF tokens. The SOF values sent by such devices differ from the USB
|
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* SOF tokens by a fixed offset that needs to be estimated and accounted
|
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* for to make timestamp recovery as accurate as possible.
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*
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* The offset is estimated the first time a device SOF value is received
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* as the difference between the host and device SOF values. As the two
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* SOF values can differ slightly due to transmission delays, consider
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* that the offset is null if the difference is not higher than 10 ms
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* (negative differences can not happen and are thus considered as an
|
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* offset). The video commit control wDelay field should be used to
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* compute a dynamic threshold instead of using a fixed 10 ms value, but
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* devices don't report reliable wDelay values.
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*
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* See uvc_video_clock_host_sof() for an explanation regarding why only
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* the 8 LSBs of the delta are kept.
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*/
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if (stream->clock.sof_offset == (u16)-1) {
|
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u16 delta_sof = (host_sof - dev_sof) & 255;
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if (delta_sof >= 10)
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stream->clock.sof_offset = delta_sof;
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else
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stream->clock.sof_offset = 0;
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}
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|
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dev_sof = (dev_sof + stream->clock.sof_offset) & 2047;
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spin_lock_irqsave(&stream->clock.lock, flags);
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sample = &stream->clock.samples[stream->clock.head];
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sample->dev_stc = get_unaligned_le32(&data[header_size - 6]);
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sample->dev_sof = dev_sof;
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sample->host_sof = host_sof;
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sample->host_ts = ts;
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|
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/* Update the sliding window head and count. */
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stream->clock.head = (stream->clock.head + 1) % stream->clock.size;
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|
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if (stream->clock.count < stream->clock.size)
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stream->clock.count++;
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|
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spin_unlock_irqrestore(&stream->clock.lock, flags);
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}
|
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|
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static int uvc_video_clock_init(struct uvc_streaming *stream)
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{
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struct uvc_clock *clock = &stream->clock;
|
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|
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spin_lock_init(&clock->lock);
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clock->head = 0;
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clock->count = 0;
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clock->size = 32;
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clock->last_sof = -1;
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clock->sof_offset = -1;
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|
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clock->samples = kmalloc(clock->size * sizeof(*clock->samples),
|
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GFP_KERNEL);
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if (clock->samples == NULL)
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return -ENOMEM;
|
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|
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return 0;
|
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}
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|
|
static void uvc_video_clock_cleanup(struct uvc_streaming *stream)
|
|
{
|
|
kfree(stream->clock.samples);
|
|
stream->clock.samples = NULL;
|
|
}
|
|
|
|
/*
|
|
* uvc_video_clock_host_sof - Return the host SOF value for a clock sample
|
|
*
|
|
* Host SOF counters reported by usb_get_current_frame_number() usually don't
|
|
* cover the whole 11-bits SOF range (0-2047) but are limited to the HCI frame
|
|
* schedule window. They can be limited to 8, 9 or 10 bits depending on the host
|
|
* controller and its configuration.
|
|
*
|
|
* We thus need to recover the SOF value corresponding to the host frame number.
|
|
* As the device and host frame numbers are sampled in a short interval, the
|
|
* difference between their values should be equal to a small delta plus an
|
|
* integer multiple of 256 caused by the host frame number limited precision.
|
|
*
|
|
* To obtain the recovered host SOF value, compute the small delta by masking
|
|
* the high bits of the host frame counter and device SOF difference and add it
|
|
* to the device SOF value.
|
|
*/
|
|
static u16 uvc_video_clock_host_sof(const struct uvc_clock_sample *sample)
|
|
{
|
|
/* The delta value can be negative. */
|
|
s8 delta_sof;
|
|
|
|
delta_sof = (sample->host_sof - sample->dev_sof) & 255;
|
|
|
|
return (sample->dev_sof + delta_sof) & 2047;
|
|
}
|
|
|
|
/*
|
|
* uvc_video_clock_update - Update the buffer timestamp
|
|
*
|
|
* This function converts the buffer PTS timestamp to the host clock domain by
|
|
* going through the USB SOF clock domain and stores the result in the V4L2
|
|
* buffer timestamp field.
|
|
*
|
|
* The relationship between the device clock and the host clock isn't known.
|
|
* However, the device and the host share the common USB SOF clock which can be
|
|
* used to recover that relationship.
|
|
*
|
|
* The relationship between the device clock and the USB SOF clock is considered
|
|
* to be linear over the clock samples sliding window and is given by
|
|
*
|
|
* SOF = m * PTS + p
|
|
*
|
|
* Several methods to compute the slope (m) and intercept (p) can be used. As
|
|
* the clock drift should be small compared to the sliding window size, we
|
|
* assume that the line that goes through the points at both ends of the window
|
|
* is a good approximation. Naming those points P1 and P2, we get
|
|
*
|
|
* SOF = (SOF2 - SOF1) / (STC2 - STC1) * PTS
|
|
* + (SOF1 * STC2 - SOF2 * STC1) / (STC2 - STC1)
|
|
*
|
|
* or
|
|
*
|
|
* SOF = ((SOF2 - SOF1) * PTS + SOF1 * STC2 - SOF2 * STC1) / (STC2 - STC1) (1)
|
|
*
|
|
* to avoid loosing precision in the division. Similarly, the host timestamp is
|
|
* computed with
|
|
*
|
|
* TS = ((TS2 - TS1) * PTS + TS1 * SOF2 - TS2 * SOF1) / (SOF2 - SOF1) (2)
|
|
*
|
|
* SOF values are coded on 11 bits by USB. We extend their precision with 16
|
|
* decimal bits, leading to a 11.16 coding.
|
|
*
|
|
* TODO: To avoid surprises with device clock values, PTS/STC timestamps should
|
|
* be normalized using the nominal device clock frequency reported through the
|
|
* UVC descriptors.
|
|
*
|
|
* Both the PTS/STC and SOF counters roll over, after a fixed but device
|
|
* specific amount of time for PTS/STC and after 2048ms for SOF. As long as the
|
|
* sliding window size is smaller than the rollover period, differences computed
|
|
* on unsigned integers will produce the correct result. However, the p term in
|
|
* the linear relations will be miscomputed.
|
|
*
|
|
* To fix the issue, we subtract a constant from the PTS and STC values to bring
|
|
* PTS to half the 32 bit STC range. The sliding window STC values then fit into
|
|
* the 32 bit range without any rollover.
|
|
*
|
|
* Similarly, we add 2048 to the device SOF values to make sure that the SOF
|
|
* computed by (1) will never be smaller than 0. This offset is then compensated
|
|
* by adding 2048 to the SOF values used in (2). However, this doesn't prevent
|
|
* rollovers between (1) and (2): the SOF value computed by (1) can be slightly
|
|
* lower than 4096, and the host SOF counters can have rolled over to 2048. This
|
|
* case is handled by subtracting 2048 from the SOF value if it exceeds the host
|
|
* SOF value at the end of the sliding window.
|
|
*
|
|
* Finally we subtract a constant from the host timestamps to bring the first
|
|
* timestamp of the sliding window to 1s.
|
|
*/
|
|
void uvc_video_clock_update(struct uvc_streaming *stream,
|
|
struct v4l2_buffer *v4l2_buf,
|
|
struct uvc_buffer *buf)
|
|
{
|
|
struct uvc_clock *clock = &stream->clock;
|
|
struct uvc_clock_sample *first;
|
|
struct uvc_clock_sample *last;
|
|
unsigned long flags;
|
|
struct timespec ts;
|
|
u32 delta_stc;
|
|
u32 y1, y2;
|
|
u32 x1, x2;
|
|
u32 mean;
|
|
u32 sof;
|
|
u32 div;
|
|
u32 rem;
|
|
u64 y;
|
|
|
|
spin_lock_irqsave(&clock->lock, flags);
|
|
|
|
if (clock->count < clock->size)
|
|
goto done;
|
|
|
|
first = &clock->samples[clock->head];
|
|
last = &clock->samples[(clock->head - 1) % clock->size];
|
|
|
|
/* First step, PTS to SOF conversion. */
|
|
delta_stc = buf->pts - (1UL << 31);
|
|
x1 = first->dev_stc - delta_stc;
|
|
x2 = last->dev_stc - delta_stc;
|
|
y1 = (first->dev_sof + 2048) << 16;
|
|
y2 = (last->dev_sof + 2048) << 16;
|
|
|
|
if (y2 < y1)
|
|
y2 += 2048 << 16;
|
|
|
|
y = (u64)(y2 - y1) * (1ULL << 31) + (u64)y1 * (u64)x2
|
|
- (u64)y2 * (u64)x1;
|
|
y = div_u64(y, x2 - x1);
|
|
|
|
sof = y;
|
|
|
|
uvc_trace(UVC_TRACE_CLOCK, "%s: PTS %u y %llu.%06llu SOF %u.%06llu "
|
|
"(x1 %u x2 %u y1 %u y2 %u SOF offset %u)\n",
|
|
stream->dev->name, buf->pts,
|
|
y >> 16, div_u64((y & 0xffff) * 1000000, 65536),
|
|
sof >> 16, div_u64(((u64)sof & 0xffff) * 1000000LLU, 65536),
|
|
x1, x2, y1, y2, clock->sof_offset);
|
|
|
|
/* Second step, SOF to host clock conversion. */
|
|
ts = timespec_sub(last->host_ts, first->host_ts);
|
|
x1 = (uvc_video_clock_host_sof(first) + 2048) << 16;
|
|
x2 = (uvc_video_clock_host_sof(last) + 2048) << 16;
|
|
y1 = NSEC_PER_SEC;
|
|
y2 = (ts.tv_sec + 1) * NSEC_PER_SEC + ts.tv_nsec;
|
|
|
|
if (x2 < x1)
|
|
x2 += 2048 << 16;
|
|
|
|
/* Interpolated and host SOF timestamps can wrap around at slightly
|
|
* different times. Handle this by adding or removing 2048 to or from
|
|
* the computed SOF value to keep it close to the SOF samples mean
|
|
* value.
|
|
*/
|
|
mean = (x1 + x2) / 2;
|
|
if (mean - (1024 << 16) > sof)
|
|
sof += 2048 << 16;
|
|
else if (sof > mean + (1024 << 16))
|
|
sof -= 2048 << 16;
|
|
|
|
y = (u64)(y2 - y1) * (u64)sof + (u64)y1 * (u64)x2
|
|
- (u64)y2 * (u64)x1;
|
|
y = div_u64(y, x2 - x1);
|
|
|
|
div = div_u64_rem(y, NSEC_PER_SEC, &rem);
|
|
ts.tv_sec = first->host_ts.tv_sec - 1 + div;
|
|
ts.tv_nsec = first->host_ts.tv_nsec + rem;
|
|
if (ts.tv_nsec >= NSEC_PER_SEC) {
|
|
ts.tv_sec++;
|
|
ts.tv_nsec -= NSEC_PER_SEC;
|
|
}
|
|
|
|
uvc_trace(UVC_TRACE_CLOCK, "%s: SOF %u.%06llu y %llu ts %lu.%06lu "
|
|
"buf ts %lu.%06lu (x1 %u/%u/%u x2 %u/%u/%u y1 %u y2 %u)\n",
|
|
stream->dev->name,
|
|
sof >> 16, div_u64(((u64)sof & 0xffff) * 1000000LLU, 65536),
|
|
y, ts.tv_sec, ts.tv_nsec / NSEC_PER_USEC,
|
|
v4l2_buf->timestamp.tv_sec, v4l2_buf->timestamp.tv_usec,
|
|
x1, first->host_sof, first->dev_sof,
|
|
x2, last->host_sof, last->dev_sof, y1, y2);
|
|
|
|
/* Update the V4L2 buffer. */
|
|
v4l2_buf->timestamp.tv_sec = ts.tv_sec;
|
|
v4l2_buf->timestamp.tv_usec = ts.tv_nsec / NSEC_PER_USEC;
|
|
|
|
done:
|
|
spin_unlock_irqrestore(&stream->clock.lock, flags);
|
|
}
|
|
|
|
/* ------------------------------------------------------------------------
|
|
* Stream statistics
|
|
*/
|
|
|
|
static void uvc_video_stats_decode(struct uvc_streaming *stream,
|
|
const __u8 *data, int len)
|
|
{
|
|
unsigned int header_size;
|
|
bool has_pts = false;
|
|
bool has_scr = false;
|
|
u16 uninitialized_var(scr_sof);
|
|
u32 uninitialized_var(scr_stc);
|
|
u32 uninitialized_var(pts);
|
|
|
|
if (stream->stats.stream.nb_frames == 0 &&
|
|
stream->stats.frame.nb_packets == 0)
|
|
ktime_get_ts(&stream->stats.stream.start_ts);
|
|
|
|
switch (data[1] & (UVC_STREAM_PTS | UVC_STREAM_SCR)) {
|
|
case UVC_STREAM_PTS | UVC_STREAM_SCR:
|
|
header_size = 12;
|
|
has_pts = true;
|
|
has_scr = true;
|
|
break;
|
|
case UVC_STREAM_PTS:
|
|
header_size = 6;
|
|
has_pts = true;
|
|
break;
|
|
case UVC_STREAM_SCR:
|
|
header_size = 8;
|
|
has_scr = true;
|
|
break;
|
|
default:
|
|
header_size = 2;
|
|
break;
|
|
}
|
|
|
|
/* Check for invalid headers. */
|
|
if (len < header_size || data[0] < header_size) {
|
|
stream->stats.frame.nb_invalid++;
|
|
return;
|
|
}
|
|
|
|
/* Extract the timestamps. */
|
|
if (has_pts)
|
|
pts = get_unaligned_le32(&data[2]);
|
|
|
|
if (has_scr) {
|
|
scr_stc = get_unaligned_le32(&data[header_size - 6]);
|
|
scr_sof = get_unaligned_le16(&data[header_size - 2]);
|
|
}
|
|
|
|
/* Is PTS constant through the whole frame ? */
|
|
if (has_pts && stream->stats.frame.nb_pts) {
|
|
if (stream->stats.frame.pts != pts) {
|
|
stream->stats.frame.nb_pts_diffs++;
|
|
stream->stats.frame.last_pts_diff =
|
|
stream->stats.frame.nb_packets;
|
|
}
|
|
}
|
|
|
|
if (has_pts) {
|
|
stream->stats.frame.nb_pts++;
|
|
stream->stats.frame.pts = pts;
|
|
}
|
|
|
|
/* Do all frames have a PTS in their first non-empty packet, or before
|
|
* their first empty packet ?
|
|
*/
|
|
if (stream->stats.frame.size == 0) {
|
|
if (len > header_size)
|
|
stream->stats.frame.has_initial_pts = has_pts;
|
|
if (len == header_size && has_pts)
|
|
stream->stats.frame.has_early_pts = true;
|
|
}
|
|
|
|
/* Do the SCR.STC and SCR.SOF fields vary through the frame ? */
|
|
if (has_scr && stream->stats.frame.nb_scr) {
|
|
if (stream->stats.frame.scr_stc != scr_stc)
|
|
stream->stats.frame.nb_scr_diffs++;
|
|
}
|
|
|
|
if (has_scr) {
|
|
/* Expand the SOF counter to 32 bits and store its value. */
|
|
if (stream->stats.stream.nb_frames > 0 ||
|
|
stream->stats.frame.nb_scr > 0)
|
|
stream->stats.stream.scr_sof_count +=
|
|
(scr_sof - stream->stats.stream.scr_sof) % 2048;
|
|
stream->stats.stream.scr_sof = scr_sof;
|
|
|
|
stream->stats.frame.nb_scr++;
|
|
stream->stats.frame.scr_stc = scr_stc;
|
|
stream->stats.frame.scr_sof = scr_sof;
|
|
|
|
if (scr_sof < stream->stats.stream.min_sof)
|
|
stream->stats.stream.min_sof = scr_sof;
|
|
if (scr_sof > stream->stats.stream.max_sof)
|
|
stream->stats.stream.max_sof = scr_sof;
|
|
}
|
|
|
|
/* Record the first non-empty packet number. */
|
|
if (stream->stats.frame.size == 0 && len > header_size)
|
|
stream->stats.frame.first_data = stream->stats.frame.nb_packets;
|
|
|
|
/* Update the frame size. */
|
|
stream->stats.frame.size += len - header_size;
|
|
|
|
/* Update the packets counters. */
|
|
stream->stats.frame.nb_packets++;
|
|
if (len > header_size)
|
|
stream->stats.frame.nb_empty++;
|
|
|
|
if (data[1] & UVC_STREAM_ERR)
|
|
stream->stats.frame.nb_errors++;
|
|
}
|
|
|
|
static void uvc_video_stats_update(struct uvc_streaming *stream)
|
|
{
|
|
struct uvc_stats_frame *frame = &stream->stats.frame;
|
|
|
|
uvc_trace(UVC_TRACE_STATS, "frame %u stats: %u/%u/%u packets, "
|
|
"%u/%u/%u pts (%searly %sinitial), %u/%u scr, "
|
|
"last pts/stc/sof %u/%u/%u\n",
|
|
stream->sequence, frame->first_data,
|
|
frame->nb_packets - frame->nb_empty, frame->nb_packets,
|
|
frame->nb_pts_diffs, frame->last_pts_diff, frame->nb_pts,
|
|
frame->has_early_pts ? "" : "!",
|
|
frame->has_initial_pts ? "" : "!",
|
|
frame->nb_scr_diffs, frame->nb_scr,
|
|
frame->pts, frame->scr_stc, frame->scr_sof);
|
|
|
|
stream->stats.stream.nb_frames++;
|
|
stream->stats.stream.nb_packets += stream->stats.frame.nb_packets;
|
|
stream->stats.stream.nb_empty += stream->stats.frame.nb_empty;
|
|
stream->stats.stream.nb_errors += stream->stats.frame.nb_errors;
|
|
stream->stats.stream.nb_invalid += stream->stats.frame.nb_invalid;
|
|
|
|
if (frame->has_early_pts)
|
|
stream->stats.stream.nb_pts_early++;
|
|
if (frame->has_initial_pts)
|
|
stream->stats.stream.nb_pts_initial++;
|
|
if (frame->last_pts_diff <= frame->first_data)
|
|
stream->stats.stream.nb_pts_constant++;
|
|
if (frame->nb_scr >= frame->nb_packets - frame->nb_empty)
|
|
stream->stats.stream.nb_scr_count_ok++;
|
|
if (frame->nb_scr_diffs + 1 == frame->nb_scr)
|
|
stream->stats.stream.nb_scr_diffs_ok++;
|
|
|
|
memset(&stream->stats.frame, 0, sizeof(stream->stats.frame));
|
|
}
|
|
|
|
size_t uvc_video_stats_dump(struct uvc_streaming *stream, char *buf,
|
|
size_t size)
|
|
{
|
|
unsigned int scr_sof_freq;
|
|
unsigned int duration;
|
|
struct timespec ts;
|
|
size_t count = 0;
|
|
|
|
ts.tv_sec = stream->stats.stream.stop_ts.tv_sec
|
|
- stream->stats.stream.start_ts.tv_sec;
|
|
ts.tv_nsec = stream->stats.stream.stop_ts.tv_nsec
|
|
- stream->stats.stream.start_ts.tv_nsec;
|
|
if (ts.tv_nsec < 0) {
|
|
ts.tv_sec--;
|
|
ts.tv_nsec += 1000000000;
|
|
}
|
|
|
|
/* Compute the SCR.SOF frequency estimate. At the nominal 1kHz SOF
|
|
* frequency this will not overflow before more than 1h.
|
|
*/
|
|
duration = ts.tv_sec * 1000 + ts.tv_nsec / 1000000;
|
|
if (duration != 0)
|
|
scr_sof_freq = stream->stats.stream.scr_sof_count * 1000
|
|
/ duration;
|
|
else
|
|
scr_sof_freq = 0;
|
|
|
|
count += scnprintf(buf + count, size - count,
|
|
"frames: %u\npackets: %u\nempty: %u\n"
|
|
"errors: %u\ninvalid: %u\n",
|
|
stream->stats.stream.nb_frames,
|
|
stream->stats.stream.nb_packets,
|
|
stream->stats.stream.nb_empty,
|
|
stream->stats.stream.nb_errors,
|
|
stream->stats.stream.nb_invalid);
|
|
count += scnprintf(buf + count, size - count,
|
|
"pts: %u early, %u initial, %u ok\n",
|
|
stream->stats.stream.nb_pts_early,
|
|
stream->stats.stream.nb_pts_initial,
|
|
stream->stats.stream.nb_pts_constant);
|
|
count += scnprintf(buf + count, size - count,
|
|
"scr: %u count ok, %u diff ok\n",
|
|
stream->stats.stream.nb_scr_count_ok,
|
|
stream->stats.stream.nb_scr_diffs_ok);
|
|
count += scnprintf(buf + count, size - count,
|
|
"sof: %u <= sof <= %u, freq %u.%03u kHz\n",
|
|
stream->stats.stream.min_sof,
|
|
stream->stats.stream.max_sof,
|
|
scr_sof_freq / 1000, scr_sof_freq % 1000);
|
|
|
|
return count;
|
|
}
|
|
|
|
static void uvc_video_stats_start(struct uvc_streaming *stream)
|
|
{
|
|
memset(&stream->stats, 0, sizeof(stream->stats));
|
|
stream->stats.stream.min_sof = 2048;
|
|
}
|
|
|
|
static void uvc_video_stats_stop(struct uvc_streaming *stream)
|
|
{
|
|
ktime_get_ts(&stream->stats.stream.stop_ts);
|
|
}
|
|
|
|
/* ------------------------------------------------------------------------
|
|
* Video codecs
|
|
*/
|
|
|
|
/* Video payload decoding is handled by uvc_video_decode_start(),
|
|
* uvc_video_decode_data() and uvc_video_decode_end().
|
|
*
|
|
* uvc_video_decode_start is called with URB data at the start of a bulk or
|
|
* isochronous payload. It processes header data and returns the header size
|
|
* in bytes if successful. If an error occurs, it returns a negative error
|
|
* code. The following error codes have special meanings.
|
|
*
|
|
* - EAGAIN informs the caller that the current video buffer should be marked
|
|
* as done, and that the function should be called again with the same data
|
|
* and a new video buffer. This is used when end of frame conditions can be
|
|
* reliably detected at the beginning of the next frame only.
|
|
*
|
|
* If an error other than -EAGAIN is returned, the caller will drop the current
|
|
* payload. No call to uvc_video_decode_data and uvc_video_decode_end will be
|
|
* made until the next payload. -ENODATA can be used to drop the current
|
|
* payload if no other error code is appropriate.
|
|
*
|
|
* uvc_video_decode_data is called for every URB with URB data. It copies the
|
|
* data to the video buffer.
|
|
*
|
|
* uvc_video_decode_end is called with header data at the end of a bulk or
|
|
* isochronous payload. It performs any additional header data processing and
|
|
* returns 0 or a negative error code if an error occurred. As header data have
|
|
* already been processed by uvc_video_decode_start, this functions isn't
|
|
* required to perform sanity checks a second time.
|
|
*
|
|
* For isochronous transfers where a payload is always transferred in a single
|
|
* URB, the three functions will be called in a row.
|
|
*
|
|
* To let the decoder process header data and update its internal state even
|
|
* when no video buffer is available, uvc_video_decode_start must be prepared
|
|
* to be called with a NULL buf parameter. uvc_video_decode_data and
|
|
* uvc_video_decode_end will never be called with a NULL buffer.
|
|
*/
|
|
static int uvc_video_decode_start(struct uvc_streaming *stream,
|
|
struct uvc_buffer *buf, const __u8 *data, int len)
|
|
{
|
|
__u8 fid;
|
|
|
|
/* Sanity checks:
|
|
* - packet must be at least 2 bytes long
|
|
* - bHeaderLength value must be at least 2 bytes (see above)
|
|
* - bHeaderLength value can't be larger than the packet size.
|
|
*/
|
|
if (len < 2 || data[0] < 2 || data[0] > len) {
|
|
stream->stats.frame.nb_invalid++;
|
|
return -EINVAL;
|
|
}
|
|
|
|
fid = data[1] & UVC_STREAM_FID;
|
|
|
|
/* Increase the sequence number regardless of any buffer states, so
|
|
* that discontinuous sequence numbers always indicate lost frames.
|
|
*/
|
|
if (stream->last_fid != fid) {
|
|
stream->sequence++;
|
|
if (stream->sequence)
|
|
uvc_video_stats_update(stream);
|
|
}
|
|
|
|
uvc_video_clock_decode(stream, buf, data, len);
|
|
uvc_video_stats_decode(stream, data, len);
|
|
|
|
/* Store the payload FID bit and return immediately when the buffer is
|
|
* NULL.
|
|
*/
|
|
if (buf == NULL) {
|
|
stream->last_fid = fid;
|
|
return -ENODATA;
|
|
}
|
|
|
|
/* Mark the buffer as bad if the error bit is set. */
|
|
if (data[1] & UVC_STREAM_ERR) {
|
|
uvc_trace(UVC_TRACE_FRAME, "Marking buffer as bad (error bit "
|
|
"set).\n");
|
|
buf->error = 1;
|
|
}
|
|
|
|
/* Synchronize to the input stream by waiting for the FID bit to be
|
|
* toggled when the the buffer state is not UVC_BUF_STATE_ACTIVE.
|
|
* stream->last_fid is initialized to -1, so the first isochronous
|
|
* frame will always be in sync.
|
|
*
|
|
* If the device doesn't toggle the FID bit, invert stream->last_fid
|
|
* when the EOF bit is set to force synchronisation on the next packet.
|
|
*/
|
|
if (buf->state != UVC_BUF_STATE_ACTIVE) {
|
|
struct timespec ts;
|
|
|
|
if (fid == stream->last_fid) {
|
|
uvc_trace(UVC_TRACE_FRAME, "Dropping payload (out of "
|
|
"sync).\n");
|
|
if ((stream->dev->quirks & UVC_QUIRK_STREAM_NO_FID) &&
|
|
(data[1] & UVC_STREAM_EOF))
|
|
stream->last_fid ^= UVC_STREAM_FID;
|
|
return -ENODATA;
|
|
}
|
|
|
|
if (uvc_clock_param == CLOCK_MONOTONIC)
|
|
ktime_get_ts(&ts);
|
|
else
|
|
ktime_get_real_ts(&ts);
|
|
|
|
buf->buf.v4l2_buf.sequence = stream->sequence;
|
|
buf->buf.v4l2_buf.timestamp.tv_sec = ts.tv_sec;
|
|
buf->buf.v4l2_buf.timestamp.tv_usec =
|
|
ts.tv_nsec / NSEC_PER_USEC;
|
|
|
|
/* TODO: Handle PTS and SCR. */
|
|
buf->state = UVC_BUF_STATE_ACTIVE;
|
|
}
|
|
|
|
/* Mark the buffer as done if we're at the beginning of a new frame.
|
|
* End of frame detection is better implemented by checking the EOF
|
|
* bit (FID bit toggling is delayed by one frame compared to the EOF
|
|
* bit), but some devices don't set the bit at end of frame (and the
|
|
* last payload can be lost anyway). We thus must check if the FID has
|
|
* been toggled.
|
|
*
|
|
* stream->last_fid is initialized to -1, so the first isochronous
|
|
* frame will never trigger an end of frame detection.
|
|
*
|
|
* Empty buffers (bytesused == 0) don't trigger end of frame detection
|
|
* as it doesn't make sense to return an empty buffer. This also
|
|
* avoids detecting end of frame conditions at FID toggling if the
|
|
* previous payload had the EOF bit set.
|
|
*/
|
|
if (fid != stream->last_fid && buf->bytesused != 0) {
|
|
uvc_trace(UVC_TRACE_FRAME, "Frame complete (FID bit "
|
|
"toggled).\n");
|
|
buf->state = UVC_BUF_STATE_READY;
|
|
return -EAGAIN;
|
|
}
|
|
|
|
stream->last_fid = fid;
|
|
|
|
return data[0];
|
|
}
|
|
|
|
static void uvc_video_decode_data(struct uvc_streaming *stream,
|
|
struct uvc_buffer *buf, const __u8 *data, int len)
|
|
{
|
|
unsigned int maxlen, nbytes;
|
|
void *mem;
|
|
|
|
if (len <= 0)
|
|
return;
|
|
|
|
/* Copy the video data to the buffer. */
|
|
maxlen = buf->length - buf->bytesused;
|
|
mem = buf->mem + buf->bytesused;
|
|
nbytes = min((unsigned int)len, maxlen);
|
|
memcpy(mem, data, nbytes);
|
|
buf->bytesused += nbytes;
|
|
|
|
/* Complete the current frame if the buffer size was exceeded. */
|
|
if (len > maxlen) {
|
|
uvc_trace(UVC_TRACE_FRAME, "Frame complete (overflow).\n");
|
|
buf->state = UVC_BUF_STATE_READY;
|
|
}
|
|
}
|
|
|
|
static void uvc_video_decode_end(struct uvc_streaming *stream,
|
|
struct uvc_buffer *buf, const __u8 *data, int len)
|
|
{
|
|
/* Mark the buffer as done if the EOF marker is set. */
|
|
if (data[1] & UVC_STREAM_EOF && buf->bytesused != 0) {
|
|
uvc_trace(UVC_TRACE_FRAME, "Frame complete (EOF found).\n");
|
|
if (data[0] == len)
|
|
uvc_trace(UVC_TRACE_FRAME, "EOF in empty payload.\n");
|
|
buf->state = UVC_BUF_STATE_READY;
|
|
if (stream->dev->quirks & UVC_QUIRK_STREAM_NO_FID)
|
|
stream->last_fid ^= UVC_STREAM_FID;
|
|
}
|
|
}
|
|
|
|
/* Video payload encoding is handled by uvc_video_encode_header() and
|
|
* uvc_video_encode_data(). Only bulk transfers are currently supported.
|
|
*
|
|
* uvc_video_encode_header is called at the start of a payload. It adds header
|
|
* data to the transfer buffer and returns the header size. As the only known
|
|
* UVC output device transfers a whole frame in a single payload, the EOF bit
|
|
* is always set in the header.
|
|
*
|
|
* uvc_video_encode_data is called for every URB and copies the data from the
|
|
* video buffer to the transfer buffer.
|
|
*/
|
|
static int uvc_video_encode_header(struct uvc_streaming *stream,
|
|
struct uvc_buffer *buf, __u8 *data, int len)
|
|
{
|
|
data[0] = 2; /* Header length */
|
|
data[1] = UVC_STREAM_EOH | UVC_STREAM_EOF
|
|
| (stream->last_fid & UVC_STREAM_FID);
|
|
return 2;
|
|
}
|
|
|
|
static int uvc_video_encode_data(struct uvc_streaming *stream,
|
|
struct uvc_buffer *buf, __u8 *data, int len)
|
|
{
|
|
struct uvc_video_queue *queue = &stream->queue;
|
|
unsigned int nbytes;
|
|
void *mem;
|
|
|
|
/* Copy video data to the URB buffer. */
|
|
mem = buf->mem + queue->buf_used;
|
|
nbytes = min((unsigned int)len, buf->bytesused - queue->buf_used);
|
|
nbytes = min(stream->bulk.max_payload_size - stream->bulk.payload_size,
|
|
nbytes);
|
|
memcpy(data, mem, nbytes);
|
|
|
|
queue->buf_used += nbytes;
|
|
|
|
return nbytes;
|
|
}
|
|
|
|
/* ------------------------------------------------------------------------
|
|
* URB handling
|
|
*/
|
|
|
|
/*
|
|
* Completion handler for video URBs.
|
|
*/
|
|
static void uvc_video_decode_isoc(struct urb *urb, struct uvc_streaming *stream,
|
|
struct uvc_buffer *buf)
|
|
{
|
|
u8 *mem;
|
|
int ret, i;
|
|
|
|
for (i = 0; i < urb->number_of_packets; ++i) {
|
|
if (urb->iso_frame_desc[i].status < 0) {
|
|
uvc_trace(UVC_TRACE_FRAME, "USB isochronous frame "
|
|
"lost (%d).\n", urb->iso_frame_desc[i].status);
|
|
/* Mark the buffer as faulty. */
|
|
if (buf != NULL)
|
|
buf->error = 1;
|
|
continue;
|
|
}
|
|
|
|
/* Decode the payload header. */
|
|
mem = urb->transfer_buffer + urb->iso_frame_desc[i].offset;
|
|
do {
|
|
ret = uvc_video_decode_start(stream, buf, mem,
|
|
urb->iso_frame_desc[i].actual_length);
|
|
if (ret == -EAGAIN)
|
|
buf = uvc_queue_next_buffer(&stream->queue,
|
|
buf);
|
|
} while (ret == -EAGAIN);
|
|
|
|
if (ret < 0)
|
|
continue;
|
|
|
|
/* Decode the payload data. */
|
|
uvc_video_decode_data(stream, buf, mem + ret,
|
|
urb->iso_frame_desc[i].actual_length - ret);
|
|
|
|
/* Process the header again. */
|
|
uvc_video_decode_end(stream, buf, mem,
|
|
urb->iso_frame_desc[i].actual_length);
|
|
|
|
if (buf->state == UVC_BUF_STATE_READY) {
|
|
if (buf->length != buf->bytesused &&
|
|
!(stream->cur_format->flags &
|
|
UVC_FMT_FLAG_COMPRESSED))
|
|
buf->error = 1;
|
|
|
|
buf = uvc_queue_next_buffer(&stream->queue, buf);
|
|
}
|
|
}
|
|
}
|
|
|
|
static void uvc_video_decode_bulk(struct urb *urb, struct uvc_streaming *stream,
|
|
struct uvc_buffer *buf)
|
|
{
|
|
u8 *mem;
|
|
int len, ret;
|
|
|
|
if (urb->actual_length == 0)
|
|
return;
|
|
|
|
mem = urb->transfer_buffer;
|
|
len = urb->actual_length;
|
|
stream->bulk.payload_size += len;
|
|
|
|
/* If the URB is the first of its payload, decode and save the
|
|
* header.
|
|
*/
|
|
if (stream->bulk.header_size == 0 && !stream->bulk.skip_payload) {
|
|
do {
|
|
ret = uvc_video_decode_start(stream, buf, mem, len);
|
|
if (ret == -EAGAIN)
|
|
buf = uvc_queue_next_buffer(&stream->queue,
|
|
buf);
|
|
} while (ret == -EAGAIN);
|
|
|
|
/* If an error occurred skip the rest of the payload. */
|
|
if (ret < 0 || buf == NULL) {
|
|
stream->bulk.skip_payload = 1;
|
|
} else {
|
|
memcpy(stream->bulk.header, mem, ret);
|
|
stream->bulk.header_size = ret;
|
|
|
|
mem += ret;
|
|
len -= ret;
|
|
}
|
|
}
|
|
|
|
/* The buffer queue might have been cancelled while a bulk transfer
|
|
* was in progress, so we can reach here with buf equal to NULL. Make
|
|
* sure buf is never dereferenced if NULL.
|
|
*/
|
|
|
|
/* Process video data. */
|
|
if (!stream->bulk.skip_payload && buf != NULL)
|
|
uvc_video_decode_data(stream, buf, mem, len);
|
|
|
|
/* Detect the payload end by a URB smaller than the maximum size (or
|
|
* a payload size equal to the maximum) and process the header again.
|
|
*/
|
|
if (urb->actual_length < urb->transfer_buffer_length ||
|
|
stream->bulk.payload_size >= stream->bulk.max_payload_size) {
|
|
if (!stream->bulk.skip_payload && buf != NULL) {
|
|
uvc_video_decode_end(stream, buf, stream->bulk.header,
|
|
stream->bulk.payload_size);
|
|
if (buf->state == UVC_BUF_STATE_READY)
|
|
buf = uvc_queue_next_buffer(&stream->queue,
|
|
buf);
|
|
}
|
|
|
|
stream->bulk.header_size = 0;
|
|
stream->bulk.skip_payload = 0;
|
|
stream->bulk.payload_size = 0;
|
|
}
|
|
}
|
|
|
|
static void uvc_video_encode_bulk(struct urb *urb, struct uvc_streaming *stream,
|
|
struct uvc_buffer *buf)
|
|
{
|
|
u8 *mem = urb->transfer_buffer;
|
|
int len = stream->urb_size, ret;
|
|
|
|
if (buf == NULL) {
|
|
urb->transfer_buffer_length = 0;
|
|
return;
|
|
}
|
|
|
|
/* If the URB is the first of its payload, add the header. */
|
|
if (stream->bulk.header_size == 0) {
|
|
ret = uvc_video_encode_header(stream, buf, mem, len);
|
|
stream->bulk.header_size = ret;
|
|
stream->bulk.payload_size += ret;
|
|
mem += ret;
|
|
len -= ret;
|
|
}
|
|
|
|
/* Process video data. */
|
|
ret = uvc_video_encode_data(stream, buf, mem, len);
|
|
|
|
stream->bulk.payload_size += ret;
|
|
len -= ret;
|
|
|
|
if (buf->bytesused == stream->queue.buf_used ||
|
|
stream->bulk.payload_size == stream->bulk.max_payload_size) {
|
|
if (buf->bytesused == stream->queue.buf_used) {
|
|
stream->queue.buf_used = 0;
|
|
buf->state = UVC_BUF_STATE_READY;
|
|
buf->buf.v4l2_buf.sequence = ++stream->sequence;
|
|
uvc_queue_next_buffer(&stream->queue, buf);
|
|
stream->last_fid ^= UVC_STREAM_FID;
|
|
}
|
|
|
|
stream->bulk.header_size = 0;
|
|
stream->bulk.payload_size = 0;
|
|
}
|
|
|
|
urb->transfer_buffer_length = stream->urb_size - len;
|
|
}
|
|
|
|
static void uvc_video_complete(struct urb *urb)
|
|
{
|
|
struct uvc_streaming *stream = urb->context;
|
|
struct uvc_video_queue *queue = &stream->queue;
|
|
struct uvc_buffer *buf = NULL;
|
|
unsigned long flags;
|
|
int ret;
|
|
|
|
switch (urb->status) {
|
|
case 0:
|
|
break;
|
|
|
|
default:
|
|
uvc_printk(KERN_WARNING, "Non-zero status (%d) in video "
|
|
"completion handler.\n", urb->status);
|
|
|
|
case -ENOENT: /* usb_kill_urb() called. */
|
|
if (stream->frozen)
|
|
return;
|
|
|
|
case -ECONNRESET: /* usb_unlink_urb() called. */
|
|
case -ESHUTDOWN: /* The endpoint is being disabled. */
|
|
uvc_queue_cancel(queue, urb->status == -ESHUTDOWN);
|
|
return;
|
|
}
|
|
|
|
spin_lock_irqsave(&queue->irqlock, flags);
|
|
if (!list_empty(&queue->irqqueue))
|
|
buf = list_first_entry(&queue->irqqueue, struct uvc_buffer,
|
|
queue);
|
|
spin_unlock_irqrestore(&queue->irqlock, flags);
|
|
|
|
stream->decode(urb, stream, buf);
|
|
|
|
if ((ret = usb_submit_urb(urb, GFP_ATOMIC)) < 0) {
|
|
uvc_printk(KERN_ERR, "Failed to resubmit video URB (%d).\n",
|
|
ret);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Free transfer buffers.
|
|
*/
|
|
static void uvc_free_urb_buffers(struct uvc_streaming *stream)
|
|
{
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < UVC_URBS; ++i) {
|
|
if (stream->urb_buffer[i]) {
|
|
#ifndef CONFIG_DMA_NONCOHERENT
|
|
usb_free_coherent(stream->dev->udev, stream->urb_size,
|
|
stream->urb_buffer[i], stream->urb_dma[i]);
|
|
#else
|
|
kfree(stream->urb_buffer[i]);
|
|
#endif
|
|
stream->urb_buffer[i] = NULL;
|
|
}
|
|
}
|
|
|
|
stream->urb_size = 0;
|
|
}
|
|
|
|
/*
|
|
* Allocate transfer buffers. This function can be called with buffers
|
|
* already allocated when resuming from suspend, in which case it will
|
|
* return without touching the buffers.
|
|
*
|
|
* Limit the buffer size to UVC_MAX_PACKETS bulk/isochronous packets. If the
|
|
* system is too low on memory try successively smaller numbers of packets
|
|
* until allocation succeeds.
|
|
*
|
|
* Return the number of allocated packets on success or 0 when out of memory.
|
|
*/
|
|
static int uvc_alloc_urb_buffers(struct uvc_streaming *stream,
|
|
unsigned int size, unsigned int psize, gfp_t gfp_flags)
|
|
{
|
|
unsigned int npackets;
|
|
unsigned int i;
|
|
|
|
/* Buffers are already allocated, bail out. */
|
|
if (stream->urb_size)
|
|
return stream->urb_size / psize;
|
|
|
|
/* Compute the number of packets. Bulk endpoints might transfer UVC
|
|
* payloads across multiple URBs.
|
|
*/
|
|
npackets = DIV_ROUND_UP(size, psize);
|
|
if (npackets > UVC_MAX_PACKETS)
|
|
npackets = UVC_MAX_PACKETS;
|
|
|
|
/* Retry allocations until one succeed. */
|
|
for (; npackets > 1; npackets /= 2) {
|
|
for (i = 0; i < UVC_URBS; ++i) {
|
|
stream->urb_size = psize * npackets;
|
|
#ifndef CONFIG_DMA_NONCOHERENT
|
|
stream->urb_buffer[i] = usb_alloc_coherent(
|
|
stream->dev->udev, stream->urb_size,
|
|
gfp_flags | __GFP_NOWARN, &stream->urb_dma[i]);
|
|
#else
|
|
stream->urb_buffer[i] =
|
|
kmalloc(stream->urb_size, gfp_flags | __GFP_NOWARN);
|
|
#endif
|
|
if (!stream->urb_buffer[i]) {
|
|
uvc_free_urb_buffers(stream);
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (i == UVC_URBS) {
|
|
uvc_trace(UVC_TRACE_VIDEO, "Allocated %u URB buffers "
|
|
"of %ux%u bytes each.\n", UVC_URBS, npackets,
|
|
psize);
|
|
return npackets;
|
|
}
|
|
}
|
|
|
|
uvc_trace(UVC_TRACE_VIDEO, "Failed to allocate URB buffers (%u bytes "
|
|
"per packet).\n", psize);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Uninitialize isochronous/bulk URBs and free transfer buffers.
|
|
*/
|
|
static void uvc_uninit_video(struct uvc_streaming *stream, int free_buffers)
|
|
{
|
|
struct urb *urb;
|
|
unsigned int i;
|
|
|
|
uvc_video_stats_stop(stream);
|
|
|
|
for (i = 0; i < UVC_URBS; ++i) {
|
|
urb = stream->urb[i];
|
|
if (urb == NULL)
|
|
continue;
|
|
|
|
usb_kill_urb(urb);
|
|
usb_free_urb(urb);
|
|
stream->urb[i] = NULL;
|
|
}
|
|
|
|
if (free_buffers)
|
|
uvc_free_urb_buffers(stream);
|
|
|
|
uvc_video_clock_cleanup(stream);
|
|
}
|
|
|
|
/*
|
|
* Initialize isochronous URBs and allocate transfer buffers. The packet size
|
|
* is given by the endpoint.
|
|
*/
|
|
static int uvc_init_video_isoc(struct uvc_streaming *stream,
|
|
struct usb_host_endpoint *ep, gfp_t gfp_flags)
|
|
{
|
|
struct urb *urb;
|
|
unsigned int npackets, i, j;
|
|
u16 psize;
|
|
u32 size;
|
|
|
|
psize = le16_to_cpu(ep->desc.wMaxPacketSize);
|
|
psize = (psize & 0x07ff) * (1 + ((psize >> 11) & 3));
|
|
size = stream->ctrl.dwMaxVideoFrameSize;
|
|
|
|
npackets = uvc_alloc_urb_buffers(stream, size, psize, gfp_flags);
|
|
if (npackets == 0)
|
|
return -ENOMEM;
|
|
|
|
size = npackets * psize;
|
|
|
|
for (i = 0; i < UVC_URBS; ++i) {
|
|
urb = usb_alloc_urb(npackets, gfp_flags);
|
|
if (urb == NULL) {
|
|
uvc_uninit_video(stream, 1);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
urb->dev = stream->dev->udev;
|
|
urb->context = stream;
|
|
urb->pipe = usb_rcvisocpipe(stream->dev->udev,
|
|
ep->desc.bEndpointAddress);
|
|
#ifndef CONFIG_DMA_NONCOHERENT
|
|
urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP;
|
|
urb->transfer_dma = stream->urb_dma[i];
|
|
#else
|
|
urb->transfer_flags = URB_ISO_ASAP;
|
|
#endif
|
|
urb->interval = ep->desc.bInterval;
|
|
urb->transfer_buffer = stream->urb_buffer[i];
|
|
urb->complete = uvc_video_complete;
|
|
urb->number_of_packets = npackets;
|
|
urb->transfer_buffer_length = size;
|
|
|
|
for (j = 0; j < npackets; ++j) {
|
|
urb->iso_frame_desc[j].offset = j * psize;
|
|
urb->iso_frame_desc[j].length = psize;
|
|
}
|
|
|
|
stream->urb[i] = urb;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Initialize bulk URBs and allocate transfer buffers. The packet size is
|
|
* given by the endpoint.
|
|
*/
|
|
static int uvc_init_video_bulk(struct uvc_streaming *stream,
|
|
struct usb_host_endpoint *ep, gfp_t gfp_flags)
|
|
{
|
|
struct urb *urb;
|
|
unsigned int npackets, pipe, i;
|
|
u16 psize;
|
|
u32 size;
|
|
|
|
psize = le16_to_cpu(ep->desc.wMaxPacketSize) & 0x07ff;
|
|
size = stream->ctrl.dwMaxPayloadTransferSize;
|
|
stream->bulk.max_payload_size = size;
|
|
|
|
npackets = uvc_alloc_urb_buffers(stream, size, psize, gfp_flags);
|
|
if (npackets == 0)
|
|
return -ENOMEM;
|
|
|
|
size = npackets * psize;
|
|
|
|
if (usb_endpoint_dir_in(&ep->desc))
|
|
pipe = usb_rcvbulkpipe(stream->dev->udev,
|
|
ep->desc.bEndpointAddress);
|
|
else
|
|
pipe = usb_sndbulkpipe(stream->dev->udev,
|
|
ep->desc.bEndpointAddress);
|
|
|
|
if (stream->type == V4L2_BUF_TYPE_VIDEO_OUTPUT)
|
|
size = 0;
|
|
|
|
for (i = 0; i < UVC_URBS; ++i) {
|
|
urb = usb_alloc_urb(0, gfp_flags);
|
|
if (urb == NULL) {
|
|
uvc_uninit_video(stream, 1);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
usb_fill_bulk_urb(urb, stream->dev->udev, pipe,
|
|
stream->urb_buffer[i], size, uvc_video_complete,
|
|
stream);
|
|
#ifndef CONFIG_DMA_NONCOHERENT
|
|
urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
|
|
urb->transfer_dma = stream->urb_dma[i];
|
|
#endif
|
|
|
|
stream->urb[i] = urb;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Initialize isochronous/bulk URBs and allocate transfer buffers.
|
|
*/
|
|
static int uvc_init_video(struct uvc_streaming *stream, gfp_t gfp_flags)
|
|
{
|
|
struct usb_interface *intf = stream->intf;
|
|
struct usb_host_endpoint *ep;
|
|
unsigned int i;
|
|
int ret;
|
|
|
|
stream->sequence = -1;
|
|
stream->last_fid = -1;
|
|
stream->bulk.header_size = 0;
|
|
stream->bulk.skip_payload = 0;
|
|
stream->bulk.payload_size = 0;
|
|
|
|
uvc_video_stats_start(stream);
|
|
|
|
ret = uvc_video_clock_init(stream);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
if (intf->num_altsetting > 1) {
|
|
struct usb_host_endpoint *best_ep = NULL;
|
|
unsigned int best_psize = 3 * 1024;
|
|
unsigned int bandwidth;
|
|
unsigned int uninitialized_var(altsetting);
|
|
int intfnum = stream->intfnum;
|
|
|
|
/* Isochronous endpoint, select the alternate setting. */
|
|
bandwidth = stream->ctrl.dwMaxPayloadTransferSize;
|
|
|
|
if (bandwidth == 0) {
|
|
uvc_trace(UVC_TRACE_VIDEO, "Device requested null "
|
|
"bandwidth, defaulting to lowest.\n");
|
|
bandwidth = 1;
|
|
} else {
|
|
uvc_trace(UVC_TRACE_VIDEO, "Device requested %u "
|
|
"B/frame bandwidth.\n", bandwidth);
|
|
}
|
|
|
|
for (i = 0; i < intf->num_altsetting; ++i) {
|
|
struct usb_host_interface *alts;
|
|
unsigned int psize;
|
|
|
|
alts = &intf->altsetting[i];
|
|
ep = uvc_find_endpoint(alts,
|
|
stream->header.bEndpointAddress);
|
|
if (ep == NULL)
|
|
continue;
|
|
|
|
/* Check if the bandwidth is high enough. */
|
|
psize = le16_to_cpu(ep->desc.wMaxPacketSize);
|
|
psize = (psize & 0x07ff) * (1 + ((psize >> 11) & 3));
|
|
if (psize >= bandwidth && psize <= best_psize) {
|
|
altsetting = i;
|
|
best_psize = psize;
|
|
best_ep = ep;
|
|
}
|
|
}
|
|
|
|
if (best_ep == NULL) {
|
|
uvc_trace(UVC_TRACE_VIDEO, "No fast enough alt setting "
|
|
"for requested bandwidth.\n");
|
|
return -EIO;
|
|
}
|
|
|
|
uvc_trace(UVC_TRACE_VIDEO, "Selecting alternate setting %u "
|
|
"(%u B/frame bandwidth).\n", altsetting, best_psize);
|
|
|
|
ret = usb_set_interface(stream->dev->udev, intfnum, altsetting);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
ret = uvc_init_video_isoc(stream, best_ep, gfp_flags);
|
|
} else {
|
|
/* Bulk endpoint, proceed to URB initialization. */
|
|
ep = uvc_find_endpoint(&intf->altsetting[0],
|
|
stream->header.bEndpointAddress);
|
|
if (ep == NULL)
|
|
return -EIO;
|
|
|
|
ret = uvc_init_video_bulk(stream, ep, gfp_flags);
|
|
}
|
|
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
/* Submit the URBs. */
|
|
for (i = 0; i < UVC_URBS; ++i) {
|
|
ret = usb_submit_urb(stream->urb[i], gfp_flags);
|
|
if (ret < 0) {
|
|
uvc_printk(KERN_ERR, "Failed to submit URB %u "
|
|
"(%d).\n", i, ret);
|
|
uvc_uninit_video(stream, 1);
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* --------------------------------------------------------------------------
|
|
* Suspend/resume
|
|
*/
|
|
|
|
/*
|
|
* Stop streaming without disabling the video queue.
|
|
*
|
|
* To let userspace applications resume without trouble, we must not touch the
|
|
* video buffers in any way. We mark the device as frozen to make sure the URB
|
|
* completion handler won't try to cancel the queue when we kill the URBs.
|
|
*/
|
|
int uvc_video_suspend(struct uvc_streaming *stream)
|
|
{
|
|
if (!uvc_queue_streaming(&stream->queue))
|
|
return 0;
|
|
|
|
stream->frozen = 1;
|
|
uvc_uninit_video(stream, 0);
|
|
usb_set_interface(stream->dev->udev, stream->intfnum, 0);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Reconfigure the video interface and restart streaming if it was enabled
|
|
* before suspend.
|
|
*
|
|
* If an error occurs, disable the video queue. This will wake all pending
|
|
* buffers, making sure userspace applications are notified of the problem
|
|
* instead of waiting forever.
|
|
*/
|
|
int uvc_video_resume(struct uvc_streaming *stream, int reset)
|
|
{
|
|
int ret;
|
|
|
|
/* If the bus has been reset on resume, set the alternate setting to 0.
|
|
* This should be the default value, but some devices crash or otherwise
|
|
* misbehave if they don't receive a SET_INTERFACE request before any
|
|
* other video control request.
|
|
*/
|
|
if (reset)
|
|
usb_set_interface(stream->dev->udev, stream->intfnum, 0);
|
|
|
|
stream->frozen = 0;
|
|
|
|
ret = uvc_commit_video(stream, &stream->ctrl);
|
|
if (ret < 0) {
|
|
uvc_queue_enable(&stream->queue, 0);
|
|
return ret;
|
|
}
|
|
|
|
if (!uvc_queue_streaming(&stream->queue))
|
|
return 0;
|
|
|
|
ret = uvc_init_video(stream, GFP_NOIO);
|
|
if (ret < 0)
|
|
uvc_queue_enable(&stream->queue, 0);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* ------------------------------------------------------------------------
|
|
* Video device
|
|
*/
|
|
|
|
/*
|
|
* Initialize the UVC video device by switching to alternate setting 0 and
|
|
* retrieve the default format.
|
|
*
|
|
* Some cameras (namely the Fuji Finepix) set the format and frame
|
|
* indexes to zero. The UVC standard doesn't clearly make this a spec
|
|
* violation, so try to silently fix the values if possible.
|
|
*
|
|
* This function is called before registering the device with V4L.
|
|
*/
|
|
int uvc_video_init(struct uvc_streaming *stream)
|
|
{
|
|
struct uvc_streaming_control *probe = &stream->ctrl;
|
|
struct uvc_format *format = NULL;
|
|
struct uvc_frame *frame = NULL;
|
|
unsigned int i;
|
|
int ret;
|
|
|
|
if (stream->nformats == 0) {
|
|
uvc_printk(KERN_INFO, "No supported video formats found.\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
atomic_set(&stream->active, 0);
|
|
|
|
/* Initialize the video buffers queue. */
|
|
uvc_queue_init(&stream->queue, stream->type, !uvc_no_drop_param);
|
|
|
|
/* Alternate setting 0 should be the default, yet the XBox Live Vision
|
|
* Cam (and possibly other devices) crash or otherwise misbehave if
|
|
* they don't receive a SET_INTERFACE request before any other video
|
|
* control request.
|
|
*/
|
|
usb_set_interface(stream->dev->udev, stream->intfnum, 0);
|
|
|
|
/* Set the streaming probe control with default streaming parameters
|
|
* retrieved from the device. Webcams that don't suport GET_DEF
|
|
* requests on the probe control will just keep their current streaming
|
|
* parameters.
|
|
*/
|
|
if (uvc_get_video_ctrl(stream, probe, 1, UVC_GET_DEF) == 0)
|
|
uvc_set_video_ctrl(stream, probe, 1);
|
|
|
|
/* Initialize the streaming parameters with the probe control current
|
|
* value. This makes sure SET_CUR requests on the streaming commit
|
|
* control will always use values retrieved from a successful GET_CUR
|
|
* request on the probe control, as required by the UVC specification.
|
|
*/
|
|
ret = uvc_get_video_ctrl(stream, probe, 1, UVC_GET_CUR);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
/* Check if the default format descriptor exists. Use the first
|
|
* available format otherwise.
|
|
*/
|
|
for (i = stream->nformats; i > 0; --i) {
|
|
format = &stream->format[i-1];
|
|
if (format->index == probe->bFormatIndex)
|
|
break;
|
|
}
|
|
|
|
if (format->nframes == 0) {
|
|
uvc_printk(KERN_INFO, "No frame descriptor found for the "
|
|
"default format.\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* Zero bFrameIndex might be correct. Stream-based formats (including
|
|
* MPEG-2 TS and DV) do not support frames but have a dummy frame
|
|
* descriptor with bFrameIndex set to zero. If the default frame
|
|
* descriptor is not found, use the first available frame.
|
|
*/
|
|
for (i = format->nframes; i > 0; --i) {
|
|
frame = &format->frame[i-1];
|
|
if (frame->bFrameIndex == probe->bFrameIndex)
|
|
break;
|
|
}
|
|
|
|
probe->bFormatIndex = format->index;
|
|
probe->bFrameIndex = frame->bFrameIndex;
|
|
|
|
stream->cur_format = format;
|
|
stream->cur_frame = frame;
|
|
|
|
/* Select the video decoding function */
|
|
if (stream->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) {
|
|
if (stream->dev->quirks & UVC_QUIRK_BUILTIN_ISIGHT)
|
|
stream->decode = uvc_video_decode_isight;
|
|
else if (stream->intf->num_altsetting > 1)
|
|
stream->decode = uvc_video_decode_isoc;
|
|
else
|
|
stream->decode = uvc_video_decode_bulk;
|
|
} else {
|
|
if (stream->intf->num_altsetting == 1)
|
|
stream->decode = uvc_video_encode_bulk;
|
|
else {
|
|
uvc_printk(KERN_INFO, "Isochronous endpoints are not "
|
|
"supported for video output devices.\n");
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Enable or disable the video stream.
|
|
*/
|
|
int uvc_video_enable(struct uvc_streaming *stream, int enable)
|
|
{
|
|
int ret;
|
|
|
|
if (!enable) {
|
|
uvc_uninit_video(stream, 1);
|
|
usb_set_interface(stream->dev->udev, stream->intfnum, 0);
|
|
uvc_queue_enable(&stream->queue, 0);
|
|
return 0;
|
|
}
|
|
|
|
ret = uvc_queue_enable(&stream->queue, 1);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
/* Commit the streaming parameters. */
|
|
ret = uvc_commit_video(stream, &stream->ctrl);
|
|
if (ret < 0) {
|
|
uvc_queue_enable(&stream->queue, 0);
|
|
return ret;
|
|
}
|
|
|
|
ret = uvc_init_video(stream, GFP_KERNEL);
|
|
if (ret < 0) {
|
|
usb_set_interface(stream->dev->udev, stream->intfnum, 0);
|
|
uvc_queue_enable(&stream->queue, 0);
|
|
}
|
|
|
|
return ret;
|
|
}
|