Suspend - Resume

All devices and device drivers are required to support system suspend mode. This mode is also known as stand-by or sleep mode.

After the device is attached to the system, the system may go into suspend mode. If the device is transmitting data, it must either stop transmitting data and pass the suspend request or it must reject the suspend request. If idle, the device driver must pass the suspend request.

While the system is in this sleep mode, there are a number of ways to wake-up the system. One is a host initiated resume command. The USB device, device driver, and application software must be able operate after the host initiated resume command.