V4L/DVB (3293): Added digital support for cx88 (cx88-alsa)

- This module is co-authored by  Ricardo Cerqueira <v4l@cerqueira.org>.

- Added digital audio support for cx88-based boards that have function
  01 enabled. These boards can be identified by having PCI id 1471:8801
  or 1471:8811.

- Increased DMA buffer from 512 to 4096 seems to fix audio distortion.

- Existing audio DMA uses conflict with cx88-alsa. Should be disabled when
  cx88-alsa module is compiled.

Signed-off-by: Ricardo Cerqueira <v4l@cerqueira.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@brturbo.com.br>

1 files changed, 4 insertions, 0 deletions

diff --git a/drivers/media/video/cx88/cx88-tvaudio.c b/drivers/media/video/cx88/cx88-tvaudio.c
index 00051a4c1dc2..24118e43e73a 100644
--- a/drivers/media/video/cx88/cx88-tvaudio.c
+++ b/drivers/media/video/cx88/cx88-tvaudio.c
@@ -132,10 +132,14 @@ static void set_audio_finish(struct cx88_core *core, u32 ctl)
 {
         u32 volume;
 
+#ifndef USING_CX88_ALSA
         /* restart dma; This avoids buzz in NICAM and is good in others  */
         cx88_stop_audio_dma(core);
+#endif
         cx_write(AUD_RATE_THRES_DMD, 0x000000C0);
+#ifndef USING_CX88_ALSA
         cx88_start_audio_dma(core);
+#endif
 
         if (cx88_boards[core->board].blackbird) {
                 /* sets sound input from external adc */