2

My Epson WF-7525 works perfectly with Ubuntu 15.04, but I have a very specific annoyance: whenever I resume my machine or plug in a USB device, the scanner comes alive as if it's briefly scanning, then stops.

It's rather noisy, and plugging in a phone nearly always triggers it. The printer-scanner seems to come out of its low power state, and I've found that I can only stop it by turning the WF-7525 off completely. This also happens for other Ubuntu machines that have the printer installed, but not for Windows or Mac machines.

I get the impression that Ubuntu is polling devices, and this is how the Workforce happens to respond to it, but I couldn't figure out which process is responsible or how to prevent it from doing so.

Is there any way to troubleshoot what's causing this, or how to disable it?

Paul Lammertsma
  • 4,256

1 Answers1

1

This question was also asked on Ask Ubuntu, which has some instructions to diagnose the problem.

For posterity, the recommendation from the only answer is:

I had a similar problem with an Epson network printer. To find out what was causing it, I used netstat to monitor the network connections while inserting a USB device:

sudo netstat -t -u -a -p -c

One connection appeared a few moments after the device was inserted: a UDP connection by colord-sane. This binary is part of colord, a "system service to manage device colour profiles".

Unfortunately, disabling this service (at least on 15.04) is more difficult than it would seem. colord is not started directly by the init system systemd. Instead, dbus starts colord, or is asked to start colord by some other service (at least not the printer service cupsd). One way to prevent this is by renaming the relevant service file:

cd /usr/share/dbus-1/system-services/
sudo mv org.freedesktop.ColorManager.service org.freedesktop.ColorManager.service.disabled

I don't know what side-effects this action might have. Another possibility is to uninstall colord completely, using

sudo apt-get remove colord

As I don't really need colour profile functionality on my Ubuntu device, I didn't investigate what exactly colord does to "activate" the printer, or how to teach it not to do so.

Community
  • 1
Paul Lammertsma
  • 4,256