Hello everyone I am using IMX6D chip and Linux3.14.52 operating system. In the process of using, we expanded 4 serial ports through eim bus + ST16C554 chip. During normal use, if we plug in a USB device, the ST16C554 chip will lose data. The reason for the lost data is because the IMX6D did not take the data from the ST16C554 chip in time. The ST16C554 chip tells the IMX6D whether there is data through an external interrupt. According to the phenomenon, when IMX6 is plugged into a USB device, it seems that it does not respond to external interrupts in time. Is there any solution to this phenomenon? We are using USB2.0 now. Is it possible to solve the problem by setting the bus to USB1.0? If yes, how can I change USB2.0 to USB1.0
