For more information about this issue, see
https://askubuntu.com/a/1106020/50254

TL;DR: Linux kernel disables 12 and 16 bit SATA Commands over UAS when
used with Seagate HDD enclosures. This usb_storage quirk is "t" instead
of "u" which forces the device into USB BOT mode. The only way to make
S.M.A.R.T. to work with USB HDD enclosure is to use UAS without
limitations - that is, no quirk of any kind.

Note that full UAS support has been disabled on all Seagate enclosures
by default because Seagate had such a poor track record with multiple
products. The quirk "t" is enough to avoid the issue and it will not
cause equal performance slowdown as the "u" quirk. Note that if you
disable all quirks with known-bad Seagate enclosure the S.M.A.R.T. will
work but you risk random data corruption if you write any data on the
disk. I guess remounting the disk read-only, disabling the "t" quirk,
doing S.M.A.R.T. query, re-enable the "t" quirk and remounting read-
write could be considered a safe workaround if you really need the
S.M.A.R.T. data.

More details about possible usb_storage.quirks:
https://www.kernel.org/doc/Documentation/admin-guide/kernel-parameters.txt

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https://bugs.launchpad.net/bugs/1810215

Title:
  for Seagate USB drive enclosures, SAT (e.g. smartmontools, hdparm)
  works on kernel 4.13 but not on 4.15

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