[PATCH 02/16] Fix NICAM buzz on analog sound

[mchehab@infradead.org]

From: Marcin Rudowski <mar_rud@poczta.onet.pl>

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>
---

 drivers/media/video/cx88/cx88-core.c |   10 ++++++----
 1 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/media/video/cx88/cx88-core.c b/drivers/media/video/cx88/cx88-core.c
index 8d6d6a6..3720f24 100644
--- a/drivers/media/video/cx88/cx88-core.c
+++ b/drivers/media/video/cx88/cx88-core.c
@@ -787,12 +787,14 @@ static int set_pll(struct cx88_core *cor
 
 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 */

-
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