[alsa-devel] [PATCH] ASoC: tlv320dac33: Use codec defaults for LOM/LOP and DAC power
Do not change the codec defaults for the following registers: 0x40, 0x41: Line output gains, do not use amplification 0x42: LOM/LOP Voltage hold, and selection 0x44: LOM inversion control
It has been found, that the values configured to these registers can cause amplification, which can make the output of DAC33 distorted.
The codec reset values are considered safe in all environmnts.
Signed-off-by: Peter Ujfalusi peter.ujfalusi@nokia.com ---
If there is a need for user control over these, than additional kcontrols can be invented for the settings. But sorting out the meaning, and naming of such controls could take considerable time. At the moment, it is safer to use the codec defaults for these instead of the original values.
sound/soc/codecs/tlv320dac33.c | 11 ----------- 1 files changed, 0 insertions(+), 11 deletions(-)
diff --git a/sound/soc/codecs/tlv320dac33.c b/sound/soc/codecs/tlv320dac33.c index 68b7ccb..ad5e263 100644 --- a/sound/soc/codecs/tlv320dac33.c +++ b/sound/soc/codecs/tlv320dac33.c @@ -303,21 +303,10 @@ static void dac33_init_chip(struct snd_soc_codec *codec) /* C : (defaults) */ dac33_write(codec, DAC33_DAC_CTRL_C, 0x00);
- /* 64-65 : L&R DAC power control - Line In -> OUT 1V/V Gain, DAC -> OUT 4V/V Gain*/ - dac33_write(codec, DAC33_LDAC_PWR_CTRL, DAC33_LROUT_GAIN(2)); - dac33_write(codec, DAC33_RDAC_PWR_CTRL, DAC33_LROUT_GAIN(2)); - /* 73 : volume soft stepping control, clock source = internal osc (?) */ dac33_write(codec, DAC33_ANA_VOL_SOFT_STEP_CTRL, DAC33_VOLCLKEN);
- /* 66 : LOP/LOM Modes */ - dac33_write(codec, DAC33_OUT_AMP_CM_CTRL, 0xff); - - /* 68 : LOM inverted from LOP */ - dac33_write(codec, DAC33_OUT_AMP_CTRL, (3<<2)); - dac33_write(codec, DAC33_PWR_CTRL, DAC33_PDNALLB);
/* Restore only selected registers (gains mostly) */
On Thu, May 06, 2010 at 12:04:25PM +0300, Peter Ujfalusi wrote:
Do not change the codec defaults for the following registers: 0x40, 0x41: Line output gains, do not use amplification 0x42: LOM/LOP Voltage hold, and selection 0x44: LOM inversion control
It has been found, that the values configured to these registers can cause amplification, which can make the output of DAC33 distorted.
The codec reset values are considered safe in all environmnts.
Signed-off-by: Peter Ujfalusi peter.ujfalusi@nokia.com
Acked-by: Mark Brown broonie@opensource.wolfsonmicro.com
On Thu, 2010-05-06 at 12:04 +0300, Peter Ujfalusi wrote:
Do not change the codec defaults for the following registers: 0x40, 0x41: Line output gains, do not use amplification 0x42: LOM/LOP Voltage hold, and selection 0x44: LOM inversion control
It has been found, that the values configured to these registers can cause amplification, which can make the output of DAC33 distorted.
The codec reset values are considered safe in all environmnts.
Signed-off-by: Peter Ujfalusi peter.ujfalusi@nokia.com
Applied.
Thanks
Liam
participants (3)
-
Liam Girdwood
-
Mark Brown
-
Peter Ujfalusi