TASCAM US-16x08 mixer support for kernel driver snd-usb-audio

**IMPORTANT**: This code was [merged upstream](https://github.com/torvalds/linux/blob/master/sound/usb/mixer_us16x08.c) in Linux 4.11.

How to apply this patch.

Download the current kernel sources and required ssl library
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sudo apt-get install libssl-dev
cd /usr/src
sudo apt-get source linux-image-$(uname -r)


Prepare kernel sources for module compilation
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cd /usr/src/<your kernel version>
cp /boot/config-$(uname -r) .config
cp /usr/src/linux-headers-$(uname -r)/Module.symvers .
make prepare
make scripts


Apply patch file
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patch --strip=1 < us16x08.path 


Compile module
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make M=sound/usb


Save original and installation
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cp /lib/modules/$(uname -r)/kernel/sound/usb/snd-usb-audio.ko <any-save-folder>
cp sound/usb/snd-usb-audio.ko /lib/modules/$(uname -r)/kernel/sound/usb/
reboot


After reboot you should be able to control the Tascam DSP (EQ/Compressor) via e.g. alsamixer/gnome-alsamixer.


Change log
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Jan-05 2017:
- added new Tascam firmware v2.00 feature DSP bypass switch.
- fixed EQ initial disabled.
- fixed Comp Release initial value to 10ms.

Jan-07 2017:
- change compressor meter poll. Poll only values for channels with actice compressor.

Jul-27 2017:
- update patch file to follow version contained in kernel version 4.12