I've bought a PQI 7-in-1 USB flash reader and after adding few quirks
it attaches like this:

umass0 at uhub0 port 1 configuration 1 interface 0
umass0: Neodio Multi-format Flash Controller, rev 1.10/1.00, addr 2
umass0: using SCSI over Bulk-Only
scsibus0 at umass0: 2 targets, 4 luns per target
scsibus0: waiting 2 seconds for devices to settle...
sd0 at scsibus0 target 1 lun 0: <Generic, USB Storage-SMC, 0090> SCSI0 0/direct removable
sd0(umass0:0:1:0):  Check Condition on CDB: 0x25 00 00 00 00 00 00 00 00 00
    SENSE KEY:  Not Ready
     ASC/ASCQ:  Medium Not Present

sd0(umass0:0:1:0): could not get size
sd0: 0, 0 cyl, 64 head, 32 sec, 512 bytes/sect x 0 sectors
sd1 at scsibus0 target 1 lun 1: <Generic, USB Storage-CFC, 0090> SCSI0 0/direct removable
sd1: 14656 KB, 14 cyl, 64 head, 32 sec, 512 bytes/sect x 29313 sectors
sd2 at scsibus0 target 1 lun 2: <Generic, USB Storage-MMC, 0090> SCSI0 0/direct removable
sd2(umass0:0:1:2):  Check Condition on CDB: 0x25 40 00 00 00 00 00 00 00 00
    SENSE KEY:  Not Ready
     ASC/ASCQ:  Medium Not Present

sd2(umass0:0:1:2): could not get size
sd2: 0, 0 cyl, 64 head, 32 sec, 512 bytes/sect x 0 sectors
sd3 at scsibus0 target 1 lun 3: <Generic, USB Storage-MSC, 0090> SCSI0 0/direct removable
sd3: 3952 KB, 3 cyl, 64 head, 32 sec, 512 bytes/sect x 7904 sectors


Is it possible to convince the kernel not to attach sdN that don't
have a flash card plugged in (sd0 and sd2 in this case), i.e. when
device reports that medium is not present?

SY, Uwe
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