Hi,
here is a patch series to add proper resume support to USB-audio quirks. So far, the control elements created directly by quirk functions aren't resumed restore_mixer_value(). This patch series try to address it.
[PATCH RFC 01/10] ALSA: usb-audio: Refactor ignore_ctl_error checks [PATCH RFC 02/10] ALSA: usb-audio: Allow quirks to handle own resume [PATCH RFC 03/10] ALSA: usb-audio: Add audigy2nx resume support [PATCH RFC 04/10] ALSA: usb-audio: Add Emu0204 channel switch resume [PATCH RFC 05/10] ALSA: usb-audio: Add Xonar U1 resume support [PATCH RFC 06/10] ALSA: usb-audio: Add Digidesign Mbox 1 resume [PATCH RFC 07/10] ALSA: usb-audio: Add resume support for Native [PATCH RFC 08/10] ALSA: usb-audio: Add resume support for FTU [PATCH RFC 09/10] ALSA: usb-audio: Add resume support for MicroII [PATCH RFC 10/10] ALSA: usb-audio: Add resume support for Scarlett
I have only compile-tested this, so far. It'd be appreciated if anyone with such devices can test with real devices.
thanks,
Takashi