Apparatus and method for supporting selective suspend mode of USB network-device

A method configured to support a selective suspend mode of a Universal Serial Bus (USB) network-device in a host, the method comprising:

• delivering a host suspend mode notification message, by a power manager, to a status manager when there is a transition to a host suspend mode;
• delivering, by the status manager, a status transition message of instructing a normal status (D0) transition to a USB driver upon receiving the host suspend mode notification message;
• transiting, by the USB driver, a power status of the USB network-device transit to a normal status (D0) in response to the status transition message;
• notifying, by the USB driver the power manager of the status transition to the normal status (D0);
• and
• transiting, by the USB driver, the power status of the USB network-device transit from the normal status (D0) to a power off status (D3) upon receiving a SetPower notification message resulting from the host suspend mode transition from the power manager.

A method for an operation of a power manager in a host equipped with a Universal Serial Bus (USB) network-device, the method comprising:

• sending a host suspend mode notification message to a status manager when there is a transition to a host suspend mode, the status manager instructing a USB driver to perform a normal status (D0) transition in response to the host suspend mode notification message;
• receiving a report that a power status of the USB network-device is equal to a normal status (D0), from the USB driver;
• and
• sending a SetPower notification message to the USB driver, and making the power status of the USB network-device transit to a power off status (D3).