Method and apparatus for SATA hot unplug

1. A method for providing serial advanced technology attachment (SATA) hot unplug, the method comprising the acts of:

detecting a physical connection of a SATA storage device to a host interface;

monitoring physical (PHY) layer signals of SATA communication lines between the host interface and the SATA storage device, by a controller of the host interface;

monitoring a phase locked loop (PLL) lock state of the PHY layer signals;

detecting physical disconnection of the SATA storage device based on the monitored PLL lock state of the PHY layer signals;

outputting a notification, by the controller, when the monitored PLL lock state of the PHY layer signals indicates that the SATA storage device has been physically disconnected; and

low pass filtering a PLL lock signal corresponding to the PLL lock state to avoid false notification that the SATA storage device has been physical disconnected.

2. The method of claim 1 , wherein detecting a connection of a SATA device relates to coupling of one or more of a SATA storage device and eSATA storage device to a host computer.

3. The method of claim 1 , wherein monitoring the PLL lock state of the PHY layer signals includes detecting unlock of a PLL response for a predetermined period of time.

4. The method of claim 1 , wherein outputting a notification relates to output on a communication bus of a host device.

5. The method of claim 1 , wherein monitoring PHY layer signals comprises detecting clock synchronization patterns embedded within the PHY layer signals.

6. The method of claim 1 , wherein monitoring PHY layer signals comprises monitoring the SATA communication lines independent of power terminals of the SATA storage device.

7. A serial advanced technology attachment (SATA) interface configured to provide hot unplug of a SATA storage device, the interface comprising:

an input interface configured to receive one or more SATA drives; and

a controller coupled to the input interface, the controller configured to:

detect a physical connection of the SATA storage device to a host interface;

monitor physical (PHY) layer signals of SATA communication lines between the host interface and the SATA storage device;

monitor a phase locked loop (PLL) lock state of the PHY layer signals;

detect physical disconnection of the SATA storage device based on the monitored PLL lock state of the PHY layer signals;

output a notification when the monitored PLL lock state of the PHY layer signals indicates that the SATA storage device has been physically disconnected; and

low pass filtering a PLL lock signal corresponding to the PLL lock state to avoid false notification that the SATA storage device has been physical disconnected.

8. The interface of claim 7 , wherein detection of a connection of a SATA device, by the controller, relates to coupling of one or more of a SATA storage device and eSATA storage device to a host computer.

9. The interface of claim 7 , wherein monitoring the PLL lock state of the PHY layer signals includes detection, by the controller, of PLL response unlock for a predetermined period of time.

10. The interface of claim 7 , wherein the controller is further configured output a notification that relates to output on a communication bus of a host device.

11. The interface of claim 7 , wherein the controller is further configured to monitor PHY layer signals by detecting clock synchronization patterns embedded within the PHY layer signals.

12. The interface of claim 7 , wherein the controller is further configured to monitor PHY layer signals by monitoring the SATA communication lines independent of power terminals of the SATA storage device.

13. A non-transitory computer program product comprising:

a computer storage medium having computer executable program code tangibly embodied therein to provide a serial advanced technology attachment (SATA) interface configured to provide hot unplug of a SATA storage device, the computer storage medium having:

computer executable program code to detect a physical connection of the SATA storage device to a host interface;

computer executable program code to monitor physical (PHY) layer signals of SATA communication lines between the host interface and the SATA storage device;

computer executable program code to monitor a phase locked loop (PLL) lock state of the PHY layer signals;

computer executable program code to detect physical disconnection of the SATA storage device based on the monitored PLL lock state of the PHY layer signals; and

computer executable program code to output a notification when the monitored PLL lock state of the PHY layer signals indicates that the SATA storage device has been physically disconnected,

low pass filtering a PLL lock signal corresponding to the PLL lock state to avoid false notification that the SATA storage device has been physical disconnected.

14. The computer program product of claim 13 , wherein detection of a connection of a SATA device, by the controller, relates to coupling of one or more of a SATA storage device and eSATA storage device to a host computer.

15. The computer program product of claim 13 , wherein computer executable program code to monitor the PLL lock state of the PHY layer signals includes computer executable program code to detect unlock of a PLL response for a predetermined period of time.

16. The computer program product of claim 13 , wherein the computer executable program code to output a notification provides output on a communication bus of a host device.

17. The computer program product of claim 13 , further comprising computer executable program code to monitor PHY layer signals by detecting clock synchronization patterns embedded within the PHY layer signals.

18. The computer program product of claim 13 , further comprising computer executable program code to monitor PHY layer signals by monitoring the SATA communication lines independent of power terminals of the SATA storage device.