USB permission on chrome book. User allows, but system blocks

[Tom Lee]

Hi All,

I have developed an Application that uses a USB card reader. The Chrome app successfully allows the USB device to be accessed on Windows and the Mac. However on a chrome book, even though the user allows permission we cannot gain access to the USB device. I looked in the system log and I see the following...

017-03-28T15:59:37.150275-05:00 INFO permission_broker[822]: ProcessPath(/dev/bus/usb/001/002)

2017-03-28T15:59:37.192680-05:00 INFO permission_broker[822]:   AllowUsbDeviceRule: ALLOW

2017-03-28T15:59:37.192697-05:00 INFO permission_broker[822]:   AllowTtyDeviceRule: IGNORE

2017-03-28T15:59:37.239417-05:00 INFO permission_broker[822]:   DenyClaimedUsbDeviceRule: DENY

2017-03-28T15:59:37.239486-05:00 INFO permission_broker[822]: Verdict for /dev/bus/usb/001/002: DENY

2017-03-28T15:59:37.239560-05:00 ERR permission_broker[822]: OpenPath(...): Domain=permission_broker, Code=permission_denied, Message=Permission to open '/dev/bus/usb/001/002' denied

I have no clue why we cannot open the device on the Chromebook. Does anybody have any clue as to what is going on?

Thanks,

Tom

[Tom Lee]

More information. We are able to use this device on other Chromebooks. But I have two Chromebooks that will not allow us to open a USB connection to this device.

Both faulty boxes have the DenyClaimedUsbDeviceRule: DENY flag set.

So we can 

1) Get permissions to the device

2) we can querty that device (chrome.usb.getDevices)

3) we cannot open the device (chrome.usb.openDevice)

Is there anyway to set the disable the DenyClaimedUsbDeviceRule rule?

[Albert Bodenhamer]

I've seen similar issues when the device ends up getting bound to some other driver on the system.  It may be getting detected as a keyboard or similar.

+Xiyuan Xia and +Rahul Chaturvedi any thoughts?

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[Tom Lee]

Thanks for responding.

I think you could be on to something. When I call GetDevices I see the correct product and vendor ID's, plus the correct manufacturer name. BUT the product name comes back as "USB Keyboard".  I also have a wireless mouse and keyboard on the usb port. I do not know if that is the cause of this or not. When I  swap out chromeboxes I get the exact same data. Strange.

It is ironic that both my Chrome Boxes show the same symptoms, but my fellow developer does not have any issues.

I am not very savvy with the Linux operating system and I am not sure how to change this.

Any suggestions would be greatly appreciated.