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AEC / DSP code on Wolfson audio card for Pi

Former Member

I have successfully compiled the Kernel and have the Wolfson audio card for Pi up and running. Took some time but I am quite happy with the audio quality.

 

Now, I would like to use the WM5102 with acoustic echo cancellation. According to the data sheet this can be enabled. Page 156, in the WM5102 documentation says:

"The WM5102 incorporates loopback signal path, which is ideally suited as a reference for Acoustic Echo Cancellation (AEC) processing. Any of the output signal paths may be selected as the AEC loopback source. When configured with suitable DSP firmware, the WM5102 can provide an integrated AEC capability."

 

My question is, does anyone know where "suitable DSP firmware" can be found and where/how it is possible to write code for the DSP?

 

I assume page 108 in the data sheet is a hint on that this must be licensed separately , it says:

"Note that the WISCETM evaluation board control software provides support for easy loading of Program, Coefficient and Data content onto the WM5102. Please contact your local Wolfson representative for more details of the WISCETM evaluation board control software."

 

Best Regards,

Joacim

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  • 0

    Hi Joacim,


    Did you make any progress in this area?  I've also just started looking into this area.  I looked at the driver source code in wm5102.c and came to the conclusion that the AEC Loopback path setting is properly configured but the AEC enable bit is never set.  Specifically, in wm5100.h, you can find the register map and the WM5100_AEC_LOOPBACK_ENA register is defined yet not used anywhere in the actual drive source code.


    I also confirmed this by dumping the wm5102 registers from debugfs and can see that only the upper bits (i.e., source select) are modified through the ALSA driver.


    Whether or not the DSP firmware actually does anything with the AEC observation path is another question, but the driver doesn't seem to support the feature fully yet.


    Modifying the driver the to actually enable the observation path would be straightforward.


    Thanks,

    Liam.


Reply
  • 0

    Hi Joacim,


    Did you make any progress in this area?  I've also just started looking into this area.  I looked at the driver source code in wm5102.c and came to the conclusion that the AEC Loopback path setting is properly configured but the AEC enable bit is never set.  Specifically, in wm5100.h, you can find the register map and the WM5100_AEC_LOOPBACK_ENA register is defined yet not used anywhere in the actual drive source code.


    I also confirmed this by dumping the wm5102 registers from debugfs and can see that only the upper bits (i.e., source select) are modified through the ALSA driver.


    Whether or not the DSP firmware actually does anything with the AEC observation path is another question, but the driver doesn't seem to support the feature fully yet.


    Modifying the driver the to actually enable the observation path would be straightforward.


    Thanks,

    Liam.


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