Comment 9 for bug 1068804

Analysis of the RT5640 part of things:

>diff -Nur playback-notworking2/tegra-rt5640/rt5640.4-001c/codec_reg playback-working2/tegra-rt5640/rt5640.4-001c/codec_reg
>--- playback-notworking2/tegra-rt5640/rt5640.4-001c/codec_reg 2012-11-07 16:59:10.000000000 +0100
>+++ playback-working2/tegra-rt5640/rt5640.4-001c/codec_reg 2012-11-07 17:02:23.000000000 +0100
>@@ -64,9 +64,9 @@
>-008e: 0004
>+008e: 0084

RT5640_DEPOP_M1

>-0090: 0646
>+0090: 0636

RT5640_DEPOP_M3

These two registers seem to be involved with headphone plug-unplug. But we have no sound from speaker either, so...?

>-00bf: 0100
>+00bf: 0180

RT5640_INT_IRQ_ST

This register is never set in code, nor is its individual bits documented.

>-00c4: 0025
>+00c4: 3fd2

RT5640_DSP_CTRL1

>-00c6: 2000
>+00c6: 253b

RT5640_DSP_CTRL3

"The DSP can be controlled through DSP command format (0xfc), addr (0xc4), data (0xc5) and cmd (0xc6) register.". As far as I know, we don't use the DSP. But I might be wrong.

>-00fc: 0000
>+00fc: 00e0

RT5640_DUMMY3

Despite its name, this register seems also related to the DSP.