[alsa-devel] [PATCH v3] sound/soc/codecs: add LAPIS Semiconductor ML26124

Lars-Peter Clausen lars at metafoo.de
Thu Dec 1 20:36:20 CET 2011

On 12/01/2011 08:46 AM, Tomoya MORINAGA wrote:
> 2011/11/29 Lars-Peter Clausen <lars at metafoo.de>:
>> Also this doesn't make much sense:
>> +       {"Input Mux", "Analog MIC in", "MICBIAS"},
>> +       {"Input Mux", "Digital MIC in", "MICBIAS"},
>> You have mux, but both possible settings of the mux connect to the same
>> source, which pretty much makes the mux useless.
> Yes, you are right.
> This setting was miss-settings.
> This MICBIAS supplies to external MIC as reference voltage.
> So, I think MICBIAS shouldn't appear at this setting.
> I show modified settings.
>        /* input */
>        {"Input Mux", "Analog MIC SingleEnded in", "MIN"},
>        {"Input Mux", "Analog MIC Differential in", "MIN"},
>        {"Input Mux", "Digital MIC in", "MDIN"},
>        {"ADC", "PGA", "Input Mux"},

The middle part(the control) of the path must either be a control attached to
the mixer on the left side(the sink) or a element of the mux's enum if a mux is
on the left side. If the left side is neither a mixer or a mux the middle part
is ignored.

The other problem probably is that you have one mux which lets you switch
between single-ended analog input, differential analog input and digital input.
The first two options are routed through PGA and ADC the later not.

- Lars

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