Arch Linux

https://bbs.archlinux.org/viewtopic.php?pid=1512876

It also happens to me. It also happens to an a4tech mouse. It is easily reproduceable by simply moving the mouse or by typing for 5 seconds.

This problem also affects my Logitech Touchpad T650 and renders it unusable. Strangely, the device is still registered in dmesg and many configuration programs without error, and if I "$cat /dev/input/mouse1", the touchpad can be seen to be sending input events, but the mouse on-screen does not respond.

The Logitech K800 keyboard connected through the Unifying was working without any problems but since kernel 3.19.2-1 I am unable to enter my cryptsetup password. The keyboard is working in the BIOS, Grub2 Menu, and after I use the keyboard on my laptop to enter the cryptsetup password I am also able to log into the system and the keyboards functions as it should.
I only see the "Invalid Device Descriptor" error while the crypsetup password prompt is waiting for input and I insert the Unifying receiver into a USB port.

In /etc/mkinitcpio.conf the module is explicitly loaded:
MODULES="hid-generic hid-logitech-dj hid-microsoft"
The hid-microsoft is their because at work I use a different keyboard.

Found the solution!
Added hid_logitech_hidpp to /etc/mkinitcpio.conf "MODULES=", it now reads:
MODULES="hid-generic hid-logitech-dj hid_logitech_hidpp hid-microsoft"
Ran:
$ mkinitcpio -p linux
And check the included modules in the new initramfs-linux.img:
$ lsinitcpio -a /boot/initramfs-linux
Now it shows, "hid-logitech-hidpp [explicit]"
Reboot and I was able to enter the cryptsetup password with my Logitech K800 again.

With the information about /etc/mkinitcpio.conf I already was half way. Because I use this laptop at different locations and not all with Logitech Unifying wireless keyboards and mice I use the explicit loading of modules. Apparently I updated to 3.19.2 kernel at a location without the Logitech Unifying so mkinitcpio autodetect hook did find the hid-logitech-hidpp modules to be loaded, which is perfectly correct, lsmod will also now show the module. If I had updated to kernel 3.19.2 at the location where my Logitech K800 was attached the /boot/initramfs-linux.img image would have contained the hid-logitech-hidpp module. So lesson learned first check the currently loaded modules with lsmod and compare them with the modules in /boot/initramfs-linux.img. ;-)

The above fix didn't do anything for me since my problem is not a problem at boot-time, but during the entirety of uptime. I'd like to also note that mouse click events *are* being sent from the T650 TouchPad if I use the hardware mouse click, but it no longer does other mouse events (movement, tapping of any kind). Rolling back to an earlier kernel did fix the problem.

I am having the same issue with the T650 TouchPad. The touch gestures don't work, so I can't move the cursor, but the hardware click works.

With Lekensteyn's help, I fixed this a while ago by adding a file to /etc/modprobe.d, but forgot to comment.
The hid_logitech_hidpp driver requires an extra argument to re-enable touch events from the T650.

The file I added contains just the line:
options hid_logitech_hidpp disable_raw_mode=1

After a reboot or removing the kernel module and modprobing with the correct args, the T650 is fully functional again.

is this issue still valid?