We can configure the DWC3 core to modify maximum speed by the command dynamically.
/* super-speed */
echo super > /sys/devices/platform/soc/a600000.ssusb/speed
/* high-speed */
echo high > /sys/devices/platform/soc/a600000.ssusb/speed
/* full-speed */
echo full > /sys/devices/platform/soc/a600000.ssusb/speed