Ippon Back Power Pro LCD connection flickers

[Hans Petter Selasky]

On 05/23/17 16:37, Lev Serebryakov wrote:
> On 22.05.2017 15:57, Hans Petter Selasky wrote:
> 
>> What is the occurrence rate of this IOERROR? Once per attach/detach.
>>
>> Did you try to connect the USB device to a different port and/or USB HUB.
>>
>> It might also be that the user-space driver tries to reset the device
>> when it sees this error. To figure that out you'll need to enable
>> debugging in the UPS software package.
>   Hans, as here are some evidences, that Linux doesn't have this problem,
> I want to track down it and help you to fix it, if it is fixable on
> FreeBSD side (maybe, with some kludge for such devices).
> 
>   I know next to nothing about Linux and USB internals, but I'm ready to
> test patches, get any dumps, try to boot Linux on this hardware and get
> dumps there, etc.

Hi,

You might try to plug the device to Linux and install the same software 
package and see what happens.

Linux has a tool similar to usbdump, that capture all USB traffic. Maybe 
this device needs some magic hint to not re-attach all the time.

Linux usually have more quirks than we do in FreeBSD. Try searching the 
internet for the idVendor and idProduct values.

--HPS