Method and system for progressive power reduction of inactive device while maintaining ready status with host

• US 8,417,979 B2
• Filed: 12/23/2010
• Issued: 04/09/2013
• Est. Priority Date: 12/23/2010
• Status: Active Grant

• Current Assignee: JP Morgan Chase Bank, N.A. (JP Morgan Chase & Co)
• Original Assignee: Western Digital Technologies Incorporated (Western Digital Corporation)
• Inventors: Maroney, John E.
• Primary Examiner(s): Wang, Albert
• Application Number:
  US12/978,376
• Publication Number:
  US 20120166828A1
• Time in Patent Office: 838 Days
• Field of Search: 710/18.19, 713/320, 713/323, 713/324
• US Class Current: 713/323
• CPC Class Codes: G06F 1/3268 Power saving in hard disk drive
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

The embodiments provide a system and method for device power control. In particular, the embodiments enable a device, such as a direct attached storage device coupled to a host, to enter into a mode that consumes less power. In one embodiment, the mode is self-initiated and triggered based on a preset timeout of non-use or other condition. Alternatively, this reduced power mode may be initiated based on a request by the host. During the reduced power mode of operation, the device may continue to appear active or on-line to its host. However, if its non-use persists, the device may employ a progression of power saving actions. If needed by the host, the direct attached storage device is configured to respond as if it were on-line and reverse one or more of the progression of power saving actions.

Claims

1. A method of controlling power consumption by a device, said method comprising:

determining when a device coupled to a host is eligible for reduced power consumption;

initiating a reduced power mode of operation by the device that consumes less power than a ready mode of operation, wherein the device continues to maintain a ready status with a host after initiating the reduced power mode; and

selectively initiating, during continued inactivity of the device, a progression of actions to reduce power consumption by the device while the device continues to maintain the ready status with the host for at least a portion of the progression of actions.

2. The method of claim 1, wherein determining when the device is eligible for reduced power consumption comprises determining when a period of inactivity by the device has exceeded a predetermined threshold.

3. The method of claim 2, wherein determining when the period of inactivity by the device has exceeded a predetermined threshold is based on a standby timer maintained by the device.

4. The method of claim 1, wherein initiating the reduced power mode of operation by the device is initiated based on a request from the host.

5. The method of claim 1, wherein initiating the reduced power mode of operation by the device is based on a self-initiated action by the device.

6. The method of claim 1, wherein initiating the reduced power mode of operation comprises providing, by the device, a universal serial bus drive identification.

7. The method of claim 1, wherein selectively initiating the progression of actions comprises spinning down a drive of the device and entering a standby state of power operation.

8. The method of claim 1, wherein selectively initiating the progression of actions comprises turning off power to a drive of the device.

9. The method of claim 1, wherein selectively initiating the progression of actions comprises disabling an internal serial ATA PHY logic of the device.

10. The method of claim 1, wherein selectively initiating the progression of actions comprises idling bridge circuitry of the device.

11. The method of claim 1, wherein selectively initiating the progression of actions comprises shutting down at least a portion of interfaces and buses of the device while maintaining an interface with the host.

12. A storage device configured to selectively reduce its power consumption, said storage device comprising:

a storage medium drive;

an interface configured to communicate a host and provide storage services for information stored on the storage medium drive; and

a controller configured to determine when the device is eligible for reduced power consumption, initiate a reduced power mode of operation by the device that consumes less power than a ready mode of operation, wherein the device continues to maintain a ready status with a host after initiating the reduced power mode, and selectively initiate, during continued inactivity of the device, a progression of actions to reduce power consumption by the device while the device continues to maintain the ready status with the host for at least a portion of the progression of actions.

13. The device of claim 12, wherein the device is a direct attached storage device and wherein the interface is a universal serial bus interface.

14. The device of claim 12, wherein the controller is configured to consume less than about 0.5 W while in the reduced power consumption mode.

15. The device of claim 12, wherein the device is configured to consume less than about 1 W from an AC main power delivered to the device.

16. The device of claim 12, wherein the device comprises an AC adapter that is compliant with an EuP standard.

17. A computing system configured to reduce its power consumption, said system comprising:

a host device;

a direct attached storage device coupled to the host device via a universal serial bus interface, wherein the direct attached storage device comprises a storage medium drive and

a controller configured to determine when the device is eligible for reduced power consumption, initiate a reduced power mode of operation by the device that consumes less power than a ready mode of operation, wherein the device continues to maintain a ready status with a host after initiating the reduced power mode, and selectively initiate, during continued inactivity of the device, a progression of actions to reduce power consumption by the device while the device continues to maintain the ready status with the host for at least a portion of the progression of actions.

18. The system of claim 17, wherein the host device is configured to initiate the reduced power mode of operation of the direct attached storage device.

19. The system of claim 17, wherein, during the reduced power mode of operation, the direct attached storage device provides a universal serial bus drive identification in response to request from the host device.

20. The system of claim 19, wherein, during the reduced power mode of operation, the direct attached storage device provides immediately with information indicating an identification of the storage medium drive, PIDs, and VIDs in response to an access request by the host device.

21. The system of claim 20, wherein in response to the access request by the host device, the direct attached storage device reverses at least some of the actions to reduce power consumption.