drivers/media/pci/ttpci/dvb_filter.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/kernel.h>
   3 #include <linux/module.h>
   4 #include <linux/string.h>
   5 #include "dvb_filter.h"
   6
   7 static u32 freq[4] = {480, 441, 320, 0};
   8
   9 static unsigned int ac3_bitrates[32] =
  10     {32,40,48,56,64,80,96,112,128,160,192,224,256,320,384,448,512,576,640,
  11      0,0,0,0,0,0,0,0,0,0,0,0,0};
  12
  13 static u32 ac3_frames[3][32] =
  14     {{64,80,96,112,128,160,192,224,256,320,384,448,512,640,768,896,1024,
  15       1152,1280,0,0,0,0,0,0,0,0,0,0,0,0,0},
  16      {69,87,104,121,139,174,208,243,278,348,417,487,557,696,835,975,1114,
  17       1253,1393,0,0,0,0,0,0,0,0,0,0,0,0,0},
  18      {96,120,144,168,192,240,288,336,384,480,576,672,768,960,1152,1344,
  19       1536,1728,1920,0,0,0,0,0,0,0,0,0,0,0,0,0}};
  20
  21 int dvb_filter_get_ac3info(u8 *mbuf, int count, struct dvb_audio_info *ai, int pr)
  22 {
  23         u8 *headr;
  24         int found = 0;
  25         int c = 0;
  26         u8 frame = 0;
  27         int fr = 0;
  28
  29         while ( !found  && c < count){
  30                 u8 *b = mbuf+c;
  31
  32                 if ( b[0] == 0x0b &&  b[1] == 0x77 )
  33                         found = 1;
  34                 else {
  35                         c++;
  36                 }
  37         }
  38
  39         if (!found) return -1;
  40         if (pr)
  41                 printk(KERN_DEBUG "Audiostream: AC3");
  42
  43         ai->off = c;
  44         if (c+5 >= count) return -1;
  45
  46         ai->layer = 0;  // 0 for AC3
  47         headr = mbuf+c+2;
  48
  49         frame = (headr[2]&0x3f);
  50         ai->bit_rate = ac3_bitrates[frame >> 1]*1000;
  51
  52         if (pr)
  53                 printk(KERN_CONT "  BRate: %d kb/s", (int) ai->bit_rate/1000);
  54
  55         ai->frequency = (headr[2] & 0xc0 ) >> 6;
  56         fr = (headr[2] & 0xc0 ) >> 6;
  57         ai->frequency = freq[fr]*100;
  58         if (pr)
  59                 printk(KERN_CONT "  Freq: %d Hz\n", (int) ai->frequency);
  60
  61         ai->framesize = ac3_frames[fr][frame >> 1];
  62         if ((frame & 1) &&  (fr == 1)) ai->framesize++;
  63         ai->framesize = ai->framesize << 1;
  64         if (pr)
  65                 printk(KERN_DEBUG "  Framesize %d\n", (int) ai->framesize);
  66
  67         return 0;
  68 }
  69
  70 void dvb_filter_pes2ts_init(struct dvb_filter_pes2ts *p2ts, unsigned short pid,
  71                             dvb_filter_pes2ts_cb_t *cb, void *priv)
  72 {
  73         unsigned char *buf=p2ts->buf;
  74
  75         buf[0]=0x47;
  76         buf[1]=(pid>>8);
  77         buf[2]=pid&0xff;
  78         p2ts->cc=0;
  79         p2ts->cb=cb;
  80         p2ts->priv=priv;
  81 }
  82
  83 int dvb_filter_pes2ts(struct dvb_filter_pes2ts *p2ts, unsigned char *pes,
  84                       int len, int payload_start)
  85 {
  86         unsigned char *buf=p2ts->buf;
  87         int ret=0, rest;
  88
  89         //len=6+((pes[4]<<8)|pes[5]);
  90
  91         if (payload_start)
  92                 buf[1]|=0x40;
  93         else
  94                 buf[1]&=~0x40;
  95         while (len>=184) {
  96                 buf[3]=0x10|((p2ts->cc++)&0x0f);
  97                 memcpy(buf+4, pes, 184);
  98                 if ((ret=p2ts->cb(p2ts->priv, buf)))
  99                         return ret;
 100                 len-=184; pes+=184;
 101                 buf[1]&=~0x40;
 102         }
 103         if (!len)
 104                 return 0;
 105         buf[3]=0x30|((p2ts->cc++)&0x0f);
 106         rest=183-len;
 107         if (rest) {
 108                 buf[5]=0x00;
 109                 if (rest-1)
 110                         memset(buf+6, 0xff, rest-1);
 111         }
 112         buf[4]=rest;
 113         memcpy(buf+5+rest, pes, len);
 114         return p2ts->cb(p2ts->priv, buf);
 115 }