How to stop attached USB device / send IRP_MN_REMOVE_DEVICE?

Sven Hazejager sven-freebsd at hazejager.nl
Tue Aug 14 07:14:18 PDT 2007


>>> So, the question really is: how to send a IRP_MN_REMOVE_DEVICE
>>> command?
>>
>> `camcontrol da? stop` seemed to do the trick before (5.2.1-R, AFAIR),
>> but now I'm not sure (looks like it doesn't)
>
> sorry, I meant to say that `camcontrol da? stop` does not power down
> the device anymore; nonetheless, it is probably safe to disconnect it

No, camcontrol does not support this over USB. Windows XP demonstrates it 
is technically possible, and I do not believe it is fully safe to 
disconnect the drive (even when unmounted), as the drive then is not able 
to park its heads, which it DOES do under XP.

So, we come back to the original question: how to send an 
IRP_MN_REMOVE_DEVICE event?

Regards,

Sven



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