[alsa-devel] Regression caused by "ASoC: core: Rework SOC_DOUBLE_R_SX_TLV add SOC_SINGLE_SX_TLV"
michael at amarulasolutions.com
Mon Feb 17 16:03:28 CET 2014
On Mon, Feb 17, 2014 at 3:59 PM, Michael Trimarchi
<michael at amarulasolutions.com> wrote:
> On Mon, Feb 17, 2014 at 2:14 PM, Thomas Petazzoni
> <thomas.petazzoni at free-electrons.com> wrote:
>> Dear Mark Brown,
>> On Fri, 14 Feb 2014 20:17:09 +0000, Mark Brown wrote:
>>> On Mon, Feb 10, 2014 at 03:22:44PM +0100, Thomas Petazzoni wrote:
>>> > On Thu, 30 Jan 2014 11:23:57 -0600, Brian Austin wrote:
>>> > > Once I get it figured out, I'll CC you on the submission for your review
>>> > > and test.
>>> > Any news about this volume control problem on cs42l51 ?
>>> What does the datasheet say about these bitfields? It should be
>>> straightforward to figure out how to fix them, it seems clear that the
>>> original code only worked by accident.
>> For the PCMA and PCMB registers (addresses 0x10 and 0x11), the
>> datasheet says that bits 0 to 6 contain the volume, and bit 7 contains
>> the mute/unmute attribute.
>> The volume can be adjusted in 0.5 dB increments, with the following
>> values described in the datasheet:
>> 001 1000 +12.0 dB
>> ........ ........
>> 000 0000 0 dB
>> 111 1111 -0.5 dB
>> 111 1110 -1.0 dB
>> ........ ........
>> 001 1001 -51.5 dB
>> Note that I haven't looked myself in details at the code of the audio
>> codec. I simply noticed there was a volume control problem and that
>> reverting Brian's patch made the volume control work again. I have not
>> investigated at all to fix the codec code, as I was suspecting that
>> Brian may have immediately an idea on what could be wrong. If he
>> doesn't have the time to look into this, I can certainly spend a bit of
>> time to investigate what's going on.
> why you don't just use regmap and check what happen on registers?
should be /sys/kernel/debug/regmap/...
>> Thomas Petazzoni, CTO, Free Electrons
>> Embedded Linux, Kernel and Android engineering
>> Alsa-devel mailing list
>> Alsa-devel at alsa-project.org
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