V4L/DVB (3266): Fix NICAM buzz on analog sound
Apparently, having the number of lines fixed at 4 reduces (or even kills) the buzz found in NICAM stereo with analog sound. Signed-off-by: Marcin Rudowski <mar_rud@poczta.onet.pl> Signed-off-by: Ricardo Cerqueira <v4l@cerqueira.org> Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
This commit is contained in:
parent
36377a19a0
commit
1b0bb68d30
1 changed files with 6 additions and 4 deletions
|
@ -787,12 +787,14 @@ static int set_pll(struct cx88_core *core, int prescale, u32 ofreq)
|
|||
|
||||
int cx88_start_audio_dma(struct cx88_core *core)
|
||||
{
|
||||
/* constant 128 made buzz in analog Nicam-stereo for bigger fifo_size */
|
||||
int bpl = cx88_sram_channels[SRAM_CH25].fifo_size/4;
|
||||
/* setup fifo + format */
|
||||
cx88_sram_channel_setup(core, &cx88_sram_channels[SRAM_CH25], 128, 0);
|
||||
cx88_sram_channel_setup(core, &cx88_sram_channels[SRAM_CH26], 128, 0);
|
||||
cx88_sram_channel_setup(core, &cx88_sram_channels[SRAM_CH25], bpl, 0);
|
||||
cx88_sram_channel_setup(core, &cx88_sram_channels[SRAM_CH26], bpl, 0);
|
||||
|
||||
cx_write(MO_AUDD_LNGTH, 128); /* fifo bpl size */
|
||||
cx_write(MO_AUDR_LNGTH, 128); /* fifo bpl size */
|
||||
cx_write(MO_AUDD_LNGTH, bpl); /* fifo bpl size */
|
||||
cx_write(MO_AUDR_LNGTH, bpl); /* fifo bpl size */
|
||||
|
||||
/* start dma */
|
||||
cx_write(MO_AUD_DMACNTRL, 0x0003); /* Up and Down fifo enable */
|
||||
|
|
Loading…
Reference in a new issue