drivers/media/platform/coda/coda-h264.c

   1 /*
   2  * Coda multi-standard codec IP - H.264 helper functions
   3  *
   4  * Copyright (C) 2012 Vista Silicon S.L.
   5  *    Javier Martin, <javier.martin@vista-silicon.com>
   6  *    Xavier Duret
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  */
  13
  14 #include <linux/kernel.h>
  15 #include <linux/string.h>
  16 #include <coda.h>
  17
  18 static const u8 coda_filler_nal[14] = { 0x00, 0x00, 0x00, 0x01, 0x0c, 0xff,
  19                         0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x80 };
  20 static const u8 coda_filler_size[8] = { 0, 7, 14, 13, 12, 11, 10, 9 };
  21
  22 int coda_h264_padding(int size, char *p)
  23 {
  24         int nal_size;
  25         int diff;
  26
  27         diff = size - (size & ~0x7);
  28         if (diff == 0)
  29                 return 0;
  30
  31         nal_size = coda_filler_size[diff];
  32         memcpy(p, coda_filler_nal, nal_size);
  33
  34         /* Add rbsp stop bit and trailing at the end */
  35         *(p + nal_size - 1) = 0x80;
  36
  37         return nal_size;
  38 }