Disabling (auto suspending) USB not working

Already asked, but no answer and so again:

Output from lsusb:

Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 010: ID 20b1:2023 XMOS Ltd
Bus 001 Device 002: ID 2109:3431 VIA Labs, Inc. Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

I’ve activated in advanced USB Auto Suspend, but it’s not working.

[root@HoerraumLuminare 1-1.2]# pwd
[root@HoerraumLuminare 1-1.2]# cat manufacturer
[root@HoerraumLuminare 1-1.2]#
[root@HoerraumLuminare 1-1.2]# cat power/*

Acticating usb auto suspend (after deactivating it) shows:

[root@HoerraumLuminare ~]# /opt/RoPieee/lib/enable_usb_auto_suspend
found USB DAC!
id: 20b1:2023
devpath: /sys/bus/usb/devices/1-1.2
auto suspend enabled!

Any hint?

There’s a reason why USB auto suspend is disabled by default: many devices don’t support it.
I suspect your device is one of them.

Thanks, so I can’t do anything?

@spockfish Harry does this actually send some USB command to the DAC or does it drop power to the USB interface for all USB ports?

No this is per port. And it is basically a request. So it’s optional and most devices do not support this.

The whole idea is that a device can act upon it and power down itself. That means if you use a DAC as pre-amp for example, that does support auto suspend, the pre-amp can power down after some time not being used. And in turn the pre-amp can power down your power amps etc. etc.

If it works it’s a very nice way of controlling power in your system. Only for the ‘if’ … :wink:

Any “known” dacs that this works with?

So, there isn’t any solution for my problem?
I’m using here an AudioValve Luminare with the DAC from Penning included.
The USB input is here sharing an analogue input. To use this analogue input, I’ve to shutdown the RPi with Ropieee or remove the USB cable.