Open maxnet opened 5 years ago
Problem is related to the serial part, and only happens if nothing is connected on the Pi side to the serial. If as a workaround I attach a getty to it ("systemctl start serial-getty@ttyGS0.service"), errors no longer appear.
Seems that the pc side (running Ubuntu) wants to set parameters on the serial as soon as it detects the USB device, judging from messages on the pc side:
[40571.121868] cdc_acm 1-2:1.2: failed to set dtr/rts
[40576.242050] cdc_acm 1-2:1.2: failed to set dtr/rts
[40593.137657] cdc_acm 1-2:1.2: failed to set dtr/rts
And that does not work if the port is not open on the gadget side. Still should not react this badly to this, to the point that MSD and Ethernet also do not work.
Describe the bug
Playing with USB gadget functions using Linux 4.19.34 on a Pi 3+ model A.
To reproduce
Connect USB port of Pi 3+ model A, to your PC.
Execute on Pi:
Expected behaviour
Expect to have working mass storage + Ethernet USB functionality exposed to host PC..
Actual behaviour
Ethernet and mass storage does appear on the host pc, but is not functional, and dmesg gives:
If doing "modprobe g_multi file=/tmp/test stall=0" instead the stalled lines no longer appear, but the timeouts do, and not functional either.