umodem0, Cisco USB serial console, and quirks

[Hans Petter Selasky]

On 09/19/17 18:15, Mike Andrews wrote:
> <OPEN|TRANSFERRING|STARTED|SHORT_XFER_OK|BDMA_ENABLE|BDMA_NO_POST_SYNC|BDMA_SETUP|CAN_CANCEL_IMMED|DOING_CALLBACK|0> 
> 
> 12:03:37.726830 usbus4.3 SUBM-BULK-EP=00000082,SPD=FULL,NFR=1,SLEN=0,IVAL=0
>   frame[0] READ 1024 bytes
>   flags 0xa <SHORT_XFER_OK|PIPE_BOF|0>
>   status 0xcf023

Hi,

Look for:

XXXX-BULK-EP=00000082

This is the USB read transfer. The other side is not returning any data, 
so neither is "cu" printing anything. Maybe you can try to get a similar 
trace from the system where it works?

Looks to me like some kind of protocol error, that the Cisco USB serial 
console needs some kind of activation.

--HPS