linux_dsm_epyc7002/drivers/media/usb/uvc/uvc_isight.c
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00

135 lines
3.6 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* uvc_isight.c -- USB Video Class driver - iSight support
*
* Copyright (C) 2006-2007
* Ivan N. Zlatev <contact@i-nz.net>
* Copyright (C) 2008-2009
* Laurent Pinchart <laurent.pinchart@ideasonboard.com>
*/
#include <linux/usb.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include "uvcvideo.h"
/* Built-in iSight webcams implements most of UVC 1.0 except a
* different packet format. Instead of sending a header at the
* beginning of each isochronous transfer payload, the webcam sends a
* single header per image (on its own in a packet), followed by
* packets containing data only.
*
* Offset Size (bytes) Description
* ------------------------------------------------------------------
* 0x00 1 Header length
* 0x01 1 Flags (UVC-compliant)
* 0x02 4 Always equal to '11223344'
* 0x06 8 Always equal to 'deadbeefdeadface'
* 0x0e 16 Unknown
*
* The header can be prefixed by an optional, unknown-purpose byte.
*/
static int isight_decode(struct uvc_video_queue *queue, struct uvc_buffer *buf,
const u8 *data, unsigned int len)
{
static const u8 hdr[] = {
0x11, 0x22, 0x33, 0x44,
0xde, 0xad, 0xbe, 0xef,
0xde, 0xad, 0xfa, 0xce
};
unsigned int maxlen, nbytes;
u8 *mem;
int is_header = 0;
if (buf == NULL)
return 0;
if ((len >= 14 && memcmp(&data[2], hdr, 12) == 0) ||
(len >= 15 && memcmp(&data[3], hdr, 12) == 0)) {
uvc_trace(UVC_TRACE_FRAME, "iSight header found\n");
is_header = 1;
}
/* Synchronize to the input stream by waiting for a header packet. */
if (buf->state != UVC_BUF_STATE_ACTIVE) {
if (!is_header) {
uvc_trace(UVC_TRACE_FRAME, "Dropping packet (out of "
"sync).\n");
return 0;
}
buf->state = UVC_BUF_STATE_ACTIVE;
}
/* Mark the buffer as done if we're at the beginning of a new frame.
*
* Empty buffers (bytesused == 0) don't trigger end of frame detection
* as it doesn't make sense to return an empty buffer.
*/
if (is_header && buf->bytesused != 0) {
buf->state = UVC_BUF_STATE_DONE;
return -EAGAIN;
}
/* Copy the video data to the buffer. Skip header packets, as they
* contain no data.
*/
if (!is_header) {
maxlen = buf->length - buf->bytesused;
mem = buf->mem + buf->bytesused;
nbytes = min(len, maxlen);
memcpy(mem, data, nbytes);
buf->bytesused += nbytes;
if (len > maxlen || buf->bytesused == buf->length) {
uvc_trace(UVC_TRACE_FRAME, "Frame complete "
"(overflow).\n");
buf->state = UVC_BUF_STATE_DONE;
}
}
return 0;
}
void uvc_video_decode_isight(struct uvc_urb *uvc_urb, struct uvc_buffer *buf,
struct uvc_buffer *meta_buf)
{
struct urb *urb = uvc_urb->urb;
struct uvc_streaming *stream = uvc_urb->stream;
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);
}
/* Decode the payload packet.
* uvc_video_decode is entered twice when a frame transition
* has been detected because the end of frame can only be
* reliably detected when the first packet of the new frame
* is processed. The first pass detects the transition and
* closes the previous frame's buffer, the second pass
* processes the data of the first payload of the new frame.
*/
do {
ret = isight_decode(&stream->queue, buf,
urb->transfer_buffer +
urb->iso_frame_desc[i].offset,
urb->iso_frame_desc[i].actual_length);
if (buf == NULL)
break;
if (buf->state == UVC_BUF_STATE_DONE ||
buf->state == UVC_BUF_STATE_ERROR)
buf = uvc_queue_next_buffer(&stream->queue,
buf);
} while (ret == -EAGAIN);
}
}