This patch is originally from Alan Stern (as557). It has been re-diffed
against a current tree, and I also corrected a minor merging error.
Some time ago we introduced a delay before device scanning, because many
devices do not like to receive SCSI commands right after enumeration.
Now it turns out there's a device that doesn't like to receive
Get-Max-LUN right after enumeration either. Accordingly this patch
delays the Get-Max-LUN request until the beginning of the scanning
procedure. This fixes Bugzilla entry #5010.
Three things are worth noting. First, I removed the locking code from
usb_stor_acquire_resources. It's not needed, because the locking is to
protect against disconnect events and acquire_resources is only called
during probe (so the disconnect routine can't be called). Second, I
initialized to 0 the buffer used for the Get-Max-LUN response. It's not
really necessary, but it will prevent random values from showing up in
the debugging log when the request fails. Third, I added a test against
the SINGLE_LUN flag. This will allow us to use the flag to indicate
Bulk-only devices that can't handle Get-Max-LUN.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Matthew Dharm <mdharm-usb@one-eyed-alien.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
b876aef7f8