kipade

I think i got the first step, I should turn the otg role to gadget mode. Just write 2 into otg_role after insert the gadget driver： echo "2" >/sys/bus/platform/devices/sunxi_usb_udc/otg_role after that, the host linux can detect new storage inserted. But, I still can't access it, I do not know why, as so far.

I use "./compile.sh BRANCH=default BOARD=orangepilite KERNEL_ONLY=no PROGRESS_DISPLAY=plain RELEASE=xenial" to build the whole booting image for my orangepi lite, it works very good as the official prebuilt armbian image. Here, the usb otg port seems configured as peripheral mode already( g_searial module works as gadget in fact), I can use it as usb seraial well. However, I want to make it works as a usb storage, so, I though the g_mass_storage was the right module. I loaded it using following command: insmode g_mass_storage.ko file=/dev/mmcblk0p1 removable=1 then, I got kernel message like: [ 194.842091] usb open backing file: /dev/mmcblk0p1, 0xd442c400 [ 194.842441] g_mass_storage gadget: Mass Storage Function, version: 2009/09/11 [ 194.842470] g_mass_storage gadget: Number of LUNs=1 [ 194.842505] lun0: LUN: removable file: /dev/mmcblk0p1 [ 194.842566] ep_matches, wrn: endpoint already claimed, ep(0xc097b2ec, 0xbf2c28f4, ep1in-bulk) [ 194.842603] g_mass_storage gadget: Mass Storage Gadget, version: 2009/09/11 [ 194.842634] g_mass_storage gadget: userspace failed to provide iSerialNumber [ 194.842673] g_mass_storage gadget: g_mass_storage ready But, I got nothing at the remote host linux, no device, no usb attaching message as g_serial. So, what should I do to make the storage gadget work? Any hints will be very very appreciated.

I can found that module at /lib/modules/3.4.113-sun8i/kernel/drivers/usb/gadget/ I use default build script, and it can be loaded on my orangepi lite. However, it can't be found by my host linux. I don't know why.