# USB device not initializing properly



## denverh (May 17, 2011)

Hello,

I have a USB device, an e-book reader, that I'm having a little trouble with.  The reader normally reports 4 LUNs: 0 is the main memory area, 1 and 2 are for expansion memory, and 3 is a read only section containing a Windows application launcher.  The problem I'm having is that whenever I plug it into my 8.2-STABLE system, LUN 0 is not ready and can't be mounted.  The information from dmesg indicates that it's reporting "not ready" and "medium not present".  LUNs 1 and 2 look exactly the same, but that's because I have no expansion memory installed.  If I rescan with *camcontrol rescan all*, then LUN 0 reports "ready" plus its correct capacity, and I can start using it.

If I check the dmesg information I get from plugging in a different device, a SanDisk drive, I see that the SanDisk initially reports "unit attention" with "medium not present". The unit attention status apparently prompts the system into doing retries of the TUR command, because I can see that same status repeated several times, until it finally returns "ready".

So it looks like the e-book reader that doesn't work properly is initially reporting "not ready", and the system does not do any retries.  The SanDisk initially reports "unit attention" instead, and the system retries the TUR, with the result that the SanDisk eventually returns "ready".

I tried to find a quirk that might take care of this, but there doesn't seem to be one.  I also searched this forum, but didn't find anything that might help me fix this.  If I missed something obvious, then forgive my poor searching skills.

Although the rescan will get the e-book reader into a working state, and I can get that done with devd.conf, I'm not sure that's the best way to take care of this.  Anybody have any better ideas?

Thanks,

Denver


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## pbd (Jun 1, 2011)

Sorry not to offer any alternative, but IMHO rescan using *devd* is the best option.


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## denverh (Jun 5, 2011)

Yes, thanks, that's what I've been doing.


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