1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* Linux driver for Philips webcam 3 Decompression frontend. 4 (C) 1999-2003 Nemosoft Unv. 5 (C) 2004-2006 Luc Saillard (luc@saillard.org) 6 7 NOTE: this version of pwc is an unofficial (modified) release of pwc & pcwx 8 driver and thus may have bugs that are not present in the original version. 9 Please send bug reports and support requests to <luc@saillard.org>. 10 The decompression routines have been implemented by reverse-engineering the 11 Nemosoft binary pwcx module. Caveat emptor. 12 13 14 vim: set ts=8: 15 */ 16 17 #include <asm/current.h> 18 #include <asm/types.h> 19 20 #include "pwc.h" 21 #include "pwc-dec1.h" 22 #include "pwc-dec23.h" 23 24 int pwc_decompress(struct pwc_device *pdev, struct pwc_frame_buf *fbuf) 25 { 26 int n, line, col; 27 void *yuv, *image; 28 u16 *src; 29 u16 *dsty, *dstu, *dstv; 30 31 image = vb2_plane_vaddr(&fbuf->vb.vb2_buf, 0); 32 33 yuv = fbuf->data + pdev->frame_header_size; /* Skip header */ 34 35 /* Raw format; that's easy... */ 36 if (pdev->pixfmt != V4L2_PIX_FMT_YUV420) 37 { 38 struct pwc_raw_frame *raw_frame = image; 39 raw_frame->type = cpu_to_le16(pdev->type); 40 raw_frame->vbandlength = cpu_to_le16(pdev->vbandlength); 41 /* cmd_buf is always 4 bytes, but sometimes, only the 42 * first 3 bytes is filled (Nala case). We can 43 * determine this using the type of the webcam */ 44 memcpy(raw_frame->cmd, pdev->cmd_buf, 4); 45 memcpy(raw_frame+1, yuv, pdev->frame_size); 46 vb2_set_plane_payload(&fbuf->vb.vb2_buf, 0, 47 pdev->frame_size + sizeof(struct pwc_raw_frame)); 48 return 0; 49 } 50 51 vb2_set_plane_payload(&fbuf->vb.vb2_buf, 0, 52 pdev->width * pdev->height * 3 / 2); 53 54 if (pdev->vbandlength == 0) { 55 /* Uncompressed mode. 56 * 57 * We do some byte shuffling here to go from the 58 * native format to YUV420P. 59 */ 60 src = (u16 *)yuv; 61 n = pdev->width * pdev->height; 62 dsty = (u16 *)(image); 63 dstu = (u16 *)(image + n); 64 dstv = (u16 *)(image + n + n / 4); 65 66 for (line = 0; line < pdev->height; line++) { 67 for (col = 0; col < pdev->width; col += 4) { 68 *dsty++ = *src++; 69 *dsty++ = *src++; 70 if (line & 1) 71 *dstv++ = *src++; 72 else 73 *dstu++ = *src++; 74 } 75 } 76 77 return 0; 78 } 79 80 /* 81 * Compressed; 82 * the decompressor routines will write the data in planar format 83 * immediately. 84 */ 85 if (DEVICE_USE_CODEC1(pdev->type)) { 86 87 /* TODO & FIXME */ 88 PWC_ERROR("This chipset is not supported for now\n"); 89 return -ENXIO; /* No such device or address: missing decompressor */ 90 91 } else { 92 pwc_dec23_decompress(pdev, yuv, image); 93 } 94 return 0; 95 } 96