linux-zen-server/drivers/media/usb/pwc/pwc-uncompress.c

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2023-08-30 17:53:23 +02:00
// SPDX-License-Identifier: GPL-2.0-or-later
/* Linux driver for Philips webcam
Decompression frontend.
(C) 1999-2003 Nemosoft Unv.
(C) 2004-2006 Luc Saillard (luc@saillard.org)
NOTE: this version of pwc is an unofficial (modified) release of pwc & pcwx
driver and thus may have bugs that are not present in the original version.
Please send bug reports and support requests to <luc@saillard.org>.
The decompression routines have been implemented by reverse-engineering the
Nemosoft binary pwcx module. Caveat emptor.
*/
#include <asm/current.h>
#include <asm/types.h>
#include "pwc.h"
#include "pwc-dec1.h"
#include "pwc-dec23.h"
int pwc_decompress(struct pwc_device *pdev, struct pwc_frame_buf *fbuf)
{
int n, line, col;
void *yuv, *image;
u16 *src;
u16 *dsty, *dstu, *dstv;
image = vb2_plane_vaddr(&fbuf->vb.vb2_buf, 0);
yuv = fbuf->data + pdev->frame_header_size; /* Skip header */
/* Raw format; that's easy... */
if (pdev->pixfmt != V4L2_PIX_FMT_YUV420)
{
struct pwc_raw_frame *raw_frame = image;
raw_frame->type = cpu_to_le16(pdev->type);
raw_frame->vbandlength = cpu_to_le16(pdev->vbandlength);
/* cmd_buf is always 4 bytes, but sometimes, only the
* first 3 bytes is filled (Nala case). We can
* determine this using the type of the webcam */
memcpy(raw_frame->cmd, pdev->cmd_buf, 4);
memcpy(raw_frame->rawframe, yuv, pdev->frame_size);
vb2_set_plane_payload(&fbuf->vb.vb2_buf, 0,
struct_size(raw_frame, rawframe, pdev->frame_size));
return 0;
}
vb2_set_plane_payload(&fbuf->vb.vb2_buf, 0,
pdev->width * pdev->height * 3 / 2);
if (pdev->vbandlength == 0) {
/* Uncompressed mode.
*
* We do some byte shuffling here to go from the
* native format to YUV420P.
*/
src = (u16 *)yuv;
n = pdev->width * pdev->height;
dsty = (u16 *)(image);
dstu = (u16 *)(image + n);
dstv = (u16 *)(image + n + n / 4);
for (line = 0; line < pdev->height; line++) {
for (col = 0; col < pdev->width; col += 4) {
*dsty++ = *src++;
*dsty++ = *src++;
if (line & 1)
*dstv++ = *src++;
else
*dstu++ = *src++;
}
}
return 0;
}
/*
* Compressed;
* the decompressor routines will write the data in planar format
* immediately.
*/
if (DEVICE_USE_CODEC1(pdev->type)) {
/* TODO & FIXME */
PWC_ERROR("This chipset is not supported for now\n");
return -ENXIO; /* No such device or address: missing decompressor */
} else {
pwc_dec23_decompress(pdev, yuv, image);
}
return 0;
}