[Nut-upsuser] CyberPower usbhid-ups continuously disconnects/reconnects

[nut at johnea.net]

Hello,

I've had this same model CyberPower connected to a linux server and a
freebsd server.

[root at sensor003 menon]# lsusb
Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 003 Device 004: ID 0764:0501 Cyber Power System, Inc. CP1500 AVR UPS
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

When the nut daemons start attempting to monitor the UPS, the device
begins a cycle of disconnecting and reconnecting every 20sec.

Running 'usbhid-ups -a nexups' manually, yields permissions issues:

[root at sensor003 menon]# usbhid-ups -a nexups
Network UPS Tools - Generic HID driver 0.34 (2.4.3)
USB communication driver 0.31
Using subdriver: CyberPower HID 0.3
libusb_get_report: could not claim interface 0: Device or resource busy
Got disconnected by another driver: Device or resource busy
Can't initialize data from HID UPS

[root at sensor003 network-ups-tools]# ls -l /dev/bus/usb/003/
total 0
crw-rw-r-- 1 root root 189, 256 Jun  7 10:55 001
crw-rw---- 1 root nut  189, 270 Jun  7 11:58 015

There is a udev rule to set permissions on this device:

[root at sensor003 menon]# cat /etc/udev/rules.d/91-local.rules
# set permissions for CyberPower UPS -jea 2010-06-02
SUBSYSTEM=="usb", ATTRS{idVendor}=="0764", GROUP="nut", MODE="0660"

The group and permissions show that this has been applied.

I'm not a linux-usb developer, and I don't quite get the depth of this,
but it seems the system hid driver is attaching to this device as it
enumerates, preventing the nut driver from attaching.

This device was finally attached before (nut 2.4) after applying the
patch mentioned here:

http://www.mail-archive.com/nut-upsuser@lists.alioth.debian.org/msg05550.html

This corrected for this low speed device not providing packets greater
than 8 bytes in length.

This patch didn't apply directly to the nut 2.6 source.

Can anyone confirm if this 8byte low speed device buffer size limit is
applied in 2.6?

Thank You Very Much!

johnea