Power managed USB for computing applications using a controller

A method, comprising:

• placing a Universal Serial Bus (USB) device in a low power state;
• sending a sideband signal to the USB device from a computer controller coupled to a computer system comprising a central processing unit to trigger the USB device to enter a normal power state, wherein the USB device is external to the computer system, wherein said sending is performed over a first medium;
• and
• wherein the USB device enters the normal power state after receiving the sideband signal, wherein data to be sent to the USB device after sending the sideband signal but before the USB device entered the normal power state is buffered;
• after the USB device enters the normal power state, performing USB communications between the USB device and said central processing unit over a second medium that is different than the first medium, wherein the computer system sending the buffered data to the USB device when the USB device is in the normal power state.

A method, comprising:

• providing a computer system having a central processing unit and a controller coupled with the central processing system;
• sending a sideband signal to the controller from a Universal Serial Bus (USB) device to trigger the computer system to enter a normal power state from a low power state, wherein the USB device is external to the computer system, and wherein said sending the sideband signal is performed over a first medium;
• wherein the computer system enters the normal power state after receiving the sideband signal;
• after the computer system enters the normal power state, performing USB communication with the computer system over a second medium that is different than the first medium;
• the USB device buffering data to send to the computer system while the computer system is in the low power state;
• and
• the USB device sending the buffered data to the computer system when the computer system enters the normal power state.

An apparatus, comprising:

• a computer system, comprising:
• a processor;
• a computer controller coupled to the processor;
• and
• a memory medium coupled to the processor;
• a Universal Serial Bus (USB) communication medium coupled to the computer system, wherein the USB communication medium is operable to transmit USB signals from the computer system to a USB device, wherein the USB device is external to the computer system;
• a sideband signal line coupled to the computer controller, wherein the sideband signal line is a separate communication medium than the USB communication medium and wherein the sideband signal line is operable to communicate a sideband signal to the USB device from the computer controller;
• and
• wherein the memory medium is operable to buffer data to send from the computer system to the USB device when the USB device is in a low power state;
• and
• wherein the computer system is operable to send the buffered data to the USB device after the USB device enters a normal power state;
• wherein the computer system is operable to trigger the USB device to enter the normal power state from the low power state by sending the USB device a sideband signal over the sideband signal line.