[alsa-devel] [PATCH 11/21] ASoC: Optimise configuration of WM8903 DC servo

Mark Brown broonie at opensource.wolfsonmicro.com
Thu Apr 23 21:55:45 CEST 2009


Modify the default startup sequence in the chip to set the DC servo
dither level for optimal performance.

Signed-off-by: Mark Brown <broonie at opensource.wolfsonmicro.com>
---
 sound/soc/codecs/wm8903.c |    5 +++++
 1 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/sound/soc/codecs/wm8903.c b/sound/soc/codecs/wm8903.c
index 27c8b94..de0a585 100644
--- a/sound/soc/codecs/wm8903.c
+++ b/sound/soc/codecs/wm8903.c
@@ -978,6 +978,11 @@ static int wm8903_set_bias_level(struct snd_soc_codec *codec,
 			wm8903_write(codec, WM8903_CLOCK_RATES_2,
 				     WM8903_CLK_SYS_ENA);
 
+			/* Change DC servo dither level in startup sequence */
+			wm8903_write(codec, WM8903_WRITE_SEQUENCER_0, 0x11);
+			wm8903_write(codec, WM8903_WRITE_SEQUENCER_1, 0x1257);
+			wm8903_write(codec, WM8903_WRITE_SEQUENCER_2, 0x2);
+
 			wm8903_run_sequence(codec, 0);
 			wm8903_sync_reg_cache(codec, codec->reg_cache);
 
-- 
1.5.6.3



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