warx, is the node still present in the output of 'cras_test_client --dump_s'?

Yes, it is still present in Input Devices list and Input Nodes list.

how about aplay -l?

Here lists the results
aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: ROCKCHIPI2S [ROCKCHIP-I2S], device 0: Audio HiFi-0 []
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 1: RockchipHDMI [RockchipHDMI], device 0: RockchipHDMI dw-hdmi-hifi-0 []
  Subdevices: 1/1
  Subdevice #0: subdevice #0



cras_test_client --dump_s
System Volume (0-100): 100 
Capture Gain (0.00 - 0.00): 0.00dB 
User muted: Muted
Output Devices:
        ID      Name
        6       ROCKCHIP-I2S: :0,0
        5       RockchipHDMI: :1,0
Output Nodes:
        Stable Id        ID      Vol   Plugged  L/R swapped           Time      Type             Name
        (79fd39ee)      6:0        81       no              no  1468604467      HEADPHONE        Headphone
        (2d5808e9)      6:1         4      yes              no  1468603747      INTERNAL_SPEAKER*Speaker
        (79401910)      5:0       100       no              no           0      HDMI             RockchipHDMI HDMI Jack
        (35ebf3cc)      5:1       100       no              no           0      HDMI             HDMI
Input Devices:
        ID      Name
        15      XI100DUSB-HDMI: USB Audio:2,0
        7       ROCKCHIP-I2S: :0,0
        4       Post DSP Loopback
        3       Post Mix Pre DSP Loopback
Input Nodes:
        Stable Id        ID     Gain   Plugged  L/R swapped           Time      Type             Name
        (d28afbb6)      15:0        0      yes              no  1468607728      USB              (default)
        (313bf2e7)      7:0         0       no              no  1468604467      MIC              ROCKCHIP-I2S Headset Jack
        (2a465a18)      7:1         0      yes              no  1468603747      INTERNAL_MIC    *Internal Mic
        (8c74f766)      4:0         0      yes              no           0      POST_DSP_LOOPBACK Post DSP Loopback
        (8a04af91)      3:0         0      yes              no           0      POST_MIX_LOOPBACK Post Mix Pre DSP Loopback
Attached clients:
        ID      pid     uid
        41      28004   0
Num active streams: 0
Last audio active time: 3212, 589455747

Sorry, should have asked for arecord -l as it's an input device.

Yes, it is there.

**** List of CAPTURE Hardware Devices ****
card 0: ROCKCHIPI2S [ROCKCHIP-I2S], device 0: Audio HiFi-0 []
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 2: XI100DUSBHDMI [XI100DUSB-HDMI], device 0: USB Audio [USB Audio]
  Subdevices: 1/1
  Subdevice #0: subdevice #0

Seems like a driver problem then.  Maybe try on a different board and your desktop Linux machine and see if it is in the core or if it is specific to a device.

Both linux desktop and chromebook pixel link are fine, no problem. I don't have more boards to test on. Please tune the owner and priority if you think are needed.

Is this on rockchip only then?  The priority is determined by if it happens on the CFM system or not.

I currently assume so because I am not able to do more tests. On my handy devices, veyron_speedy only.

You should get a CfM device, that's the only one that matters for this use case.

no problem for CFM device 

after unplug, arecord -l, still reports an ALSA device for many seconds.
 http://www.magewell.com/usb-capture-hdmi

The magewell USB capture card requires USB 3.0, does veyron_speedy support USB 3.0?  If not the device might behave strangely.

Veyron doesn't support USB 3.0 this might be an issue .

Activating. Please assign to the right owner and the appropriate priority.

This issue has been Available for over a year. If it's no longer important or seems unlikely to be fixed, please consider closing it out. If it is important, please re-triage the issue.

Sorry for the inconvenience if the bug really should have been left as Available.

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

This bug has an owner, thus, it's been triaged. Changing status to "assigned".