Am Mi., 30. Juni 2021 um 11:28 Uhr schrieb Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx>: > On Wed, Jun 30, 2021 at 10:55:04AM +0200, Benjamin Marty wrote: > > On the iMX8 device `Linux imx8mm-var-dart 5.4.3-g050b21f4b394 #1 SMP > > PREEMPT Fri Oct 9 11:36:53 PDT 2020 aarch64 GNU/Linux` and on the > > Raspberry Pi device `Linux raspberry 5.10.17-v7l+ #1403 SMP Mon Feb 22 > > 11:33:35 GMT 2021 armv7l GNU/Linux`. > > I do not understand, which is the host and which is the gadget here? I use both as Gadget, two different HW platforms to rule out a Hardware related issue. As Host, I've tried multiple normal Intel computers. I was able to reproduce this issue with all HW Combinations > > File write to `/dev/hidg0` starts to hang when there was high mass > > storage traffic. It also doesn't recover itself. There is no `complete > > kernel lockup`. > > File write on the host or gadget? File write on the gadget to the gadget HID device `/dev/hidg0` > If things are not locked up, what is stalled? The File write to the gadget HID device is stalled. > > I haven't used usbmon yet but if I don't have high traffic scenarios > > on the mass storage then the mass storage and HID device works as > > expected. So I'm confident that I send the correct data. > > That's fine, but it is good to use usbmon to see what the errors are as > well when things go wrong. Unfortunately both Kernel Versions don't have the usbmon module, need to recompile the Kernel first. > > Also saw that I'm getting this error in dmesg on both devices: > > [ 1895.677053] configfs-gadget gadget: End Point Request ERROR: -108 > > Ah, is your userspace code on the gadget not handling this properly? > What userspace code is running on the gadget for your USB device > emulation? Yes, my userspace code is on the gadget. It runs after I've setup the gadget HID + gadget Mass Storage. But it starts to fail after High Traffic scenarios to the gadget Mass Storage. To replicate the issue, I wrote a simple Bash script which just wiggles the gadget HID (Mouse) every 50ms: while true; do if [ -e "/dev/hidg0" ]; then echo write0 echo \\x00\\xff\\xff\\x00\\xff\\xff > /dev/hidg0 sleep 0.05 echo write1 echo \\x00\\xff\\xff\\x00\\xff\\x00 > /dev/hidg0 sleep 0.05 fi done Do I need to check something before writing to the gadget HID device? Or should this usage of the gadget HID device be fine? Thanks Benjamin
