saa7134 - размер FIFO

Ну вот такие строчки там есть, их и надо менять.

        /* RAM FIFO config */
        saa_writel(SAA7134_FIFO_SIZE, 0x08070503);
        saa_writel(SAA7134_THRESHOULD,0x02020202);

FIFO configuration
A0h       31:28    -    -  Reserved. Should be set to zero.
          27:24    ERA4 8h End of Ram Area 4. Hardwired to 8h. Read only.
          23:20    -    -  Reserved. Should be set to zero.
          19:16    ERA3 7h End of Ram Area 3. Equals begin of RAM area 4. Do not change
                           this value if any channel is active! Make sure that ERA3 is greater
                           equal than ERA2 and smaller or equal than ERA4!
          15:12    -    -  Reserved. Should be set to zero.
          11:8     ERA2 7h End of Ram Area 2. Equals begin of RAM area 3. Do not change
                           this value if any channel is active! Make sure that ERA2 is greater
                           equal than ERA1 and smaller or equal than ERA3!
          7:4      -    -  Reserved. Should be set to zero.
          3:0      ERA1 7h End of Ram Area1. Equals begin of RAM area 2. Do not change th
                           value if any channel is active! Make sure that ERA1 is smaller or
                           equal than ERA2!
A4h       31:26    -    -  Reserved. Should be set to zero.
          25:24    THR4 2h Threshold for RAM area 4
          23:18    -    -  Reserved. Should be set to zero.
          17:16    THR3 2h Threshold for RAM area 3
          15:10    -    -  Reserved. Should be set to zero.
          9:8      THR2 2h Threshold for RAM area 2
          7:2      -    -  Reserved. Should be set to zero.
          1:0      THR1 1h Threshold for RAM area 1