Several boards failed, but squawks/link/chell/big/elm/daisy passed : 
https://wmatrix.googleplex.com/unfiltered?suites=usb_detect&releases=57&tests=platform_SuspendResumeTiming*

https://screenshot.googleplex.com/H4n7io1BUab

Failed boards passed regular usb peripherals tests like platform_ExternalUsbPeripherals.detect.login_closelid_openlid

It's very interesting that Elm never passed ExternalUsbPeripherals.detect* tests due to missing one of the peripherals, but platform_SuspendResumeTiming* cases passed. 

log snippet: 
12/19 19:14:47.519 DEBUG|          ssh_host:0177| Running (ssh) 'lsusb'
12/19 19:14:48.258 DEBUG|        base_utils:0280| [stdout] Bus 001 Device 004: ID 0424:ec00 Standard Microsystems Corp. SMSC9512/9514 Fast Ethernet Adapter
12/19 19:14:48.259 DEBUG|        base_utils:0280| [stdout] Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
12/19 19:14:48.259 DEBUG|        base_utils:0280| [stdout] Bus 001 Device 005: ID 8087:0a2a Intel Corp. 
12/19 19:14:48.259 DEBUG|        base_utils:0280| [stdout] Bus 001 Device 003: ID 04f2:b490 Chicony Electronics Co., Ltd 
12/19 19:14:48.259 DEBUG|        base_utils:0280| [stdout] Bus 001 Device 002: ID 0424:9514 Standard Microsystems Corp. SMC9514 Hub
12/19 19:14:48.259 DEBUG|        base_utils:0280| [stdout] Bus 001 Device 006: ID 13b1:0041 Linksys 
12/19 19:14:48.259 DEBUG|        base_utils:0280| [stdout] Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
12/19 19:14:48.429 INFO |             servo:0512| Setting prtctl4_pwren to off
12/19 19:14:50.773 INFO |             servo:0512| Setting usb_mux_sel1 to dut_sees_usbkey
12/19 19:14:53.113 INFO |             servo:0512| Setting prtctl4_pwren to on
12/19 19:14:53.359 INFO |             servo:0512| Setting usb_mux_sel3 to dut_sees_usbkey
12/19 19:14:53.632 INFO |             servo:0512| Setting dut_hub1_rst1 to off
12/19 19:14:58.952 DEBUG|          ssh_host:0177| Running (ssh) 'lsusb'
12/19 19:15:09.232 DEBUG|        base_utils:0280| [stdout] Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
12/19 19:15:09.232 DEBUG|        base_utils:0280| [stdout] Bus 001 Device 005: ID 8087:0a2a Intel Corp. 
12/19 19:15:09.232 DEBUG|        base_utils:0280| [stdout] Bus 001 Device 003: ID 04f2:b490 Chicony Electronics Co., Ltd 
12/19 19:15:09.232 DEBUG|        base_utils:0280| [stdout] Bus 001 Device 011: ID 0424:9514 Standard Microsystems Corp. SMC9514 Hub
12/19 19:15:09.232 DEBUG|        base_utils:0280| [stdout] Bus 001 Device 006: ID 13b1:0041 Linksys 
12/19 19:15:09.232 DEBUG|        base_utils:0280| [stdout] Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
12/19 19:15:09.312 WARNI|              test:0606| Autotest caught exception when running test:
Traceback (most recent call last):
  File "/usr/local/autotest/client/common_lib/test.py", line 600, in _exec
    _call_test_function(self.execute, *p_args, **p_dargs)
  File "/usr/local/autotest/client/common_lib/test.py", line 804, in _call_test_function
    return func(*args, **dargs)
  File "/usr/local/autotest/client/common_lib/test.py", line 461, in execute
    dargs)
  File "/usr/local/autotest/client/common_lib/test.py", line 347, in _call_run_once_with_retry
    postprocess_profiled_run, args, dargs)
  File "/usr/local/autotest/client/common_lib/test.py", line 376, in _call_run_once
    self.run_once(*args, **dargs)
  File "/usr/local/autotest/server/site_tests/platform_SuspendResumeTiming/platform_SuspendResumeTiming.py", line 131, in run_once
    raise error.TestFail('No peripherals are connected to servo!')
TestFail: No peripherals are connected to servo!