Bsrgvty

I had the same problem. In my case, S.M.A.R.T had been working properly on the device for years while using Ubuntu 12.04, and then under Ubuntu 14.04 it happened exactly what you tell in the question.

The problem is related to a new kernel module that was introduced in Linux Kernel 3.15 called uas (USB Attached SCSI) (see release announcement).

That module is now the responsible of managing USB Mass Storage Devices. There is a thread where people complain that uas in kernel 3.15 is causing their USB devices to fail. Another one says that it might be the cause of S.M.A.R.T problems.

Fortunately, those problems seem to be gone at kernel 3.19 (which I am using), as my device is being detected correctly. Only the S.M.A.R.T problem remains.

To fix it, you need to disable the use of uas module for the given device.

Disable uas without rebooting

First, unplug all USB devices that might be using it. Then, remove the uas and usb-storage modules:

sudo modprobe -r uas
sudo modprobe -r usb-storage

Then, load usb-storage module with a parameter that tells it to not use uas for a given device:

sudo modprobe usb-storage quirks=VendorId:ProductId:u

VendorId and ProductId must be replaced by your device vendor and product id, which can be obtained with lsusb command (they are the characters after ID).

For example, I have the following device:

Bus 002 Device 011: ID 0bc2:3320 Seagate RSS LLC SRD00F2 [Expansion Desktop Drive]

So my vendor id is 0bc2, and my product id is 3320. My command is:

sudo modprobe usb-storage quirks=0bc2:3320:u

The last u tells usb-storage to ignore uas for the device (see source).

At this point, you can insert the USB device, and it will know not to use uas, making S.M.A.R.T work properly. You will see lines like these in dmesg when inserting the USB device:

usb 2-2: UAS is blacklisted for this device, using usb-storage instead
usb-storage 2-2:1.0: USB Mass Storage device detected
usb-storage 2-2:1.0: Quirks match for vid 0bc2 pid 3320: 800000
scsi host12: usb-storage 2-2:1.0

Make the change permanent

The previous quirk will only last until you reboot the system. To make it persistent, you need to follow the steps described here, which I copy below:

First, create a file named ignore_uas.conf in the /etc/modprobe.d/ directory with the following content:

options usb-storage quirks=VendorId:ProductId:u

As before, substitute VendorId and ProductId by your device vendor and product id obtained from lsusb.

Next, regenerate your inital ramdisk:

mkinitcpio -p linux

or, on newer Ubuntu versions:

sudo update-initramfs -u

Finally, reboot your computer.

Edit:
More background on the issue, and another way to get around it without disabling uas (which has better throughput than usb-storage) can be found here: https://www.smartmontools.org/ticket/971#comment:12

It seems that kernel is blacklisting SAT ATA PASS-THROUGH on some devices when running in uas mode, as they have broken firmware.

So, the blacklisting can be disabled (at your own risk) by using the previous method I mention in the answer, but removing the final u from the quirk, ie:

quirks=VendorId:ProductId:

Please note, however, that I have not tested this approach.

External drives (via USB, I assume) are tricky with SMART. Some don't work at all. The smartmontools people posted a list of hard drives with command-line switches to add to smartctl (see fifth column).

For Seagate Expansion drives in particular, it looks like you need either -d sat or -d sat,12. Try the following:

sudo smartctl -d sat --all /dev/sdb
sudo smartctl -d sat,12 --all /dev/sdb

If one of those works, it tells you which -d switch to add to your smartctl commands.

check the table with supported USB Devices ...

the switch -d sat indicates, that it's supposed to be a drive with SATA port.

there are specific switches for certain USB bridges - lsusb might show the concrete name. if the bridge controller might have a bad implementation - just try to connect it native through SATA instead of USB.

SCSI and ATA (according to the shell output) are probably not what you are looking for :)

I had two Seagate drives connected so I modified @Terrance command to:

echo "options usb-storage quirks=$(lsusb | awk '/Seagate/ print $6":u"' | tr 'n' ',' | head -c-1)" | sudo tee -a /etc/modprobe.d/ignore_uas.conf

Which gives a correct separator (and flag repetition) for multiple elements:

options usb-storage quirks=0bc2:3320:u,0bc2:2323:u

This substitution of 'newline' characters by ',' is probably not made in the most elegant way (requires to remove the extra separator using head), but it seems to work.

Then:

sudo update-initramfs -u

And reboot as in original answer.

Just an update I am adding on to Alvaro's answer

Just tested this in Ubuntu 18.04 for an external Seagate drive that I have where I could not get smartctl to read the drive at all. It did require a reboot because I did not want to get behind my system and mess with the USB connections.

First ran lsusb and got all my info for the drive:

terrance@terrance-ubuntu:~$ lsusb
Bus 006 Device 002: ID 0bc2:a0a4 Seagate RSS LLC Backup Plus Desktop Drive
Bus 006 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 005 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 004 Device 002: ID 1532:0118 Razer USA, Ltd 
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 003: ID 046d:c215 Logitech, Inc. Extreme 3D Pro
Bus 003 Device 002: ID 1532:005b Razer USA, Ltd 
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub

As you can see my drive has the name Seagate in it, so all I had to do is to run the following line to add the info to the /etc/modprode.d/ignore_uas.conf file:

echo options usb-storage quirks=$(lsusb | awk '/Seagate/ print $6'):u | sudo tee -a /etc/modprobe.d/ignore_uas.conf

Just remember to replace Seagate with the name of your drive. Now when I look at /etc/modprode.d/ignore_uas.conf I see it as:

~$ cat /etc/modprobe.d/ignore_uas.conf 
options usb-storage quirks=0bc2:a0a4:u

Then just run the update-initramfs for the changes to become permanent:

sudo update-initramfs -u

Then reboot your system. Now the smartctl is able to read my external drive.

$ sudo smartctl -a /dev/sdf
smartctl 6.6 2016-05-31 r4324 [x86_64-linux-4.15.0-43-generic] (local build)
Copyright (C) 2002-16, Bruce Allen, Christian Franke, www.smartmontools.org

=== START OF INFORMATION SECTION ===
Model Family: Seagate Barracuda 7200.14 (AF)
Device Model: ST3000DM001-1E6166
Serial Number: W1F3DNG2
LU WWN Device Id: 5 000c50 06a323610
Firmware Version: SC47
User Capacity: 3,000,592,982,016 bytes [3.00 TB]
Sector Sizes: 512 bytes logical, 4096 bytes physical
Rotation Rate: 7200 rpm
Form Factor: 3.5 inches
Device is: In smartctl database [for details use: -P show]
ATA Version is: ATA8-ACS T13/1699-D revision 4
SATA Version is: SATA 3.0, 6.0 Gb/s (current: 3.0 Gb/s)
Local Time is: Fri Jan 11 23:07:43 2019 MST
SMART support is: Available - device has SMART capability.
SMART support is: Enabled

=== START OF READ SMART DATA SECTION ===
SMART overall-health self-assessment test result: PASSED
See vendor-specific Attribute list for marginal Attributes.

General SMART Values:
Offline data collection status: (0x00) Offline data collection activity
 was never started.
 Auto Offline Data Collection: Disabled.
Self-test execution status: ( 0) The previous self-test routine completed
 without error or no self-test has ever 
 been run.
Total time to complete Offline 
data collection: ( 592) seconds.
Offline data collection
capabilities: (0x73) SMART execute Offline immediate.
 Auto Offline data collection on/off support.
 Suspend Offline collection upon new
 command.
 No Offline surface scan supported.
 Self-test supported.
 Conveyance Self-test supported.
 Selective Self-test supported.
SMART capabilities: (0x0003) Saves SMART data before entering
 power-saving mode.
 Supports SMART auto save timer.
Error logging capability: (0x01) Error logging supported.
 General Purpose Logging supported.
Short self-test routine 
recommended polling time: ( 1) minutes.
Extended self-test routine
recommended polling time: ( 336) minutes.
Conveyance self-test routine
recommended polling time: ( 2) minutes.
SCT capabilities: (0x3081) SCT Status supported.

SMART Attributes Data Structure revision number: 10
Vendor Specific SMART Attributes with Thresholds:
ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE
 1 Raw_Read_Error_Rate 0x000f 108 099 006 Pre-fail Always - 19766104
 3 Spin_Up_Time 0x0003 094 091 000 Pre-fail Always - 0
 4 Start_Stop_Count 0x0032 097 097 020 Old_age Always - 3944
 5 Reallocated_Sector_Ct 0x0033 100 100 010 Pre-fail Always - 0
 7 Seek_Error_Rate 0x000f 052 048 030 Pre-fail Always - 231936780154
 9 Power_On_Hours 0x0032 058 058 000 Old_age Always - 36793
 10 Spin_Retry_Count 0x0013 100 100 097 Pre-fail Always - 0
 12 Power_Cycle_Count 0x0032 097 097 020 Old_age Always - 3942
183 Runtime_Bad_Block 0x0032 100 100 000 Old_age Always - 0
184 End-to-End_Error 0x0032 100 100 099 Old_age Always - 0
187 Reported_Uncorrect 0x0032 100 100 000 Old_age Always - 0
188 Command_Timeout 0x0032 100 092 000 Old_age Always - 894 897 1362
189 High_Fly_Writes 0x003a 100 100 000 Old_age Always - 0
190 Airflow_Temperature_Cel 0x0022 056 039 045 Old_age Always In_the_past 44 (Min/Max 44/44 #237)
191 G-Sense_Error_Rate 0x0032 100 100 000 Old_age Always - 0
192 Power-Off_Retract_Count 0x0032 099 099 000 Old_age Always - 3909
193 Load_Cycle_Count 0x0032 020 020 000 Old_age Always - 161838
194 Temperature_Celsius 0x0022 044 061 000 Old_age Always - 44 (0 13 0 0 0)
197 Current_Pending_Sector 0x0012 100 100 000 Old_age Always - 0
198 Offline_Uncorrectable 0x0010 100 100 000 Old_age Offline - 0
199 UDMA_CRC_Error_Count 0x003e 200 200 000 Old_age Always - 0
240 Head_Flying_Hours 0x0000 100 253 000 Old_age Offline - 8558h+07m+38.053s
241 Total_LBAs_Written 0x0000 100 253 000 Old_age Offline - 14574986552
242 Total_LBAs_Read 0x0000 100 253 000 Old_age Offline - 18776308038

SMART Error Log Version: 1
No Errors Logged

SMART Self-test log structure revision number 1
No self-tests have been logged. [To run self-tests, use: smartctl -t]

SMART Selective self-test log data structure revision number 1
 SPAN MIN_LBA MAX_LBA CURRENT_TEST_STATUS
 1 0 0 Not_testing
 2 0 0 Not_testing
 3 0 0 Not_testing
 4 0 0 Not_testing
 5 0 0 Not_testing
Selective self-test flags (0x0):
 After scanning selected spans, do NOT read-scan remainder of disk.
If Selective self-test is pending on power-up, resume after 0 minute delay.

Hope this helps!