Linux kernel: 2.6.35
Build system: Timesys Factory
Processor: Freescale i.MX53
Build target: custom board (based on i.MX53 Quick Start Board)
Three USB “ports”: Host1, Host3 and Device. Host3 and Device ports are exposed externally.
- A custom Kernel configuration was created to enable the operation of USB Host3 port.
- A composite CDC USB device (serial + Ethernet + mass-storage) driver is attached to the Device port (note: this driver is compiled into the kernel and is not a kernel module).
- When the USB device port is plugged into a PC during boot, the host PC system port sometimes fails to enumerate the Device. On some PC host systems this happens fairly consistently. On other systems, this is a rare occurrence (i.e. 1 time in 20 or more attempts). Re-plugging the cable into USB Device port does not result in the port working.
- When certain USB mass-storage devices are plugged into the USB Host3 port on boot, the port will stop working, such that “dmesg” reports nothing when the device is unplugged and re-plugged.
We are looking for solutions or a work-around to these issues. While rebooting the system without the Host and Device ports plugged in, works around the issue; rebooting is not a viable workaround for us.