On Mon, May 18, 2020, at 6:58 PM, Peter Chen wrote: > > > > 2. Try exactly the same script I gave you, do not try change any > > > charaters (except the position for your application) > > > > > > > > cd /sys/kernel/config/usb_gadget > > > > > cd g1 > > > > > echo "0x1d6b" > idVendor > > > > > echo "0x0105" > idProduct > > > > > mkdir /dev/usb-ffs > > > > > mkdir functions/ffs.usb > > > > > mount -t functionfs usb /dev/usb-ffs ln -s functions/ffs.usb > > > > > configs/c.1 /home/root/usb_test/ffs_test/ffs-test & /* your own > > > > > test application */ while [ ! -e /dev/usb-ffs/ep1 ] do echo "." > > > > > sleep 1; > > > > > done > > > > > > > > > > > [1]: I actually did not have CONFIG_USB_CONFIGFS_F_FS nor F_NCM/ECM > > set however the necessary code seemed to have been pulled in some other way > > and the modules were available. They were loaded, and as explained my shell- > > based configfs code worked. They are set now and the problem persists. > > > > > > > Hi, sorry I was not clear. The kernel config is fine, and > > CONFIG_USB_CONFIGFS_F_FS is set. I run your exact script (minus the ffs-test > > line) and it fails to create the functions/ffs.usb directory as I described before. I can > > create other functions just fine. > > You may enable debug at configfs.c, f_fs.c and your udc driver to see > what happened. > Thanks for your help Peter. Unfortunately I have hit a brick wall. The examples in libusbgx also fail to work, and I tried that library after a friend recommended it as perhaps having secret mojo. I enabled the userspace debug helpers in the kernel but they do not seem to offer me any insight, and there's no relevant dmesg output. My device is an Allwinner H2+, and the UDC seems to be the Inventra Highspeed Dual Role Controller. I've also got the DesignWare USB3/USB2 cores enabled from my upstream but I think they are not being loaded. If anyone can look I'd appreciate it, this is just a hobby project. It's a good chance for me to do some kernel debugging but I'm a bit lost. Thanks for the help so far.
