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Subject: Re: [edk2-devel] EFI_AUDIO_OUTPUT_PROTOCOL: assistance with VirtIO initialization
To: devel@edk2.groups.io, harlydavidsen@gmail.com
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From: "Michael Brown" <mcb30@ipxe.org>
Message-ID: <f81fc950-d368-15be-92ea-56c251ee597f@ipxe.org>
Date: Thu, 1 Jul 2021 15:15:47 +0100
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On 01/07/2021 00:01, Ethin Probst wrote:
> So Leif and I have been working on USB Audio but we've run into a snag. 
> We've encountered a problem -- neither of us knows enough about USB to 
> figure out how to get the class-specific AC interface descriptors, and 
> those contain vital information that I need to be able to control the 
> audio device.

Do you mean that you can't figure out how to retrieve the descriptors 
via the UEFI APIs, or that you don't know how to interpret the 
descriptors after retrieval?

Thanks,

Michael