Methods and physical computer-readable storage media for initiating re-enumeration of USB 3.0 compatible devices

• US 9,864,607 B2
• Filed: 03/31/2015
• Issued: 01/09/2018
• Est. Priority Date: 09/29/2011
• Status: Active Grant

• Current Assignee: Cypress Semiconductor Corporation (Infineon Technologies AG)
• Original Assignee: Cypress Semiconductor Corporation (Infineon Technologies AG)
• Inventors: Bajpai, Pradeep, Rundell, Robert
• Primary Examiner(s): Tsai, Henry
• Assistant Examiner(s): ROCHE, JOHN B
• Application Number:
  US14/675,128
• Publication Number:
  US 20150286549A1
• Time in Patent Office: 1,015 Days
• CPC Class Codes: G06F 11/3041 where the computing system component is an input/output interface interconnection of, or transfer of information or other signals between, memories, input/output devices or central processing units G06F13/00
• CPC Class Codes: G06F 11/3055 Monitoring arrangements for monitoring the status of the computing system or of the computing system component, e.g. monitoring if the computing system is on, off, available, not available error or fault processing without redundancy G06F11/0703; error detection or correction by redundancy in data representation G06F11/08; error detection or correction by redundancy in operation G06F11/14; error detection or correction by redundancy in hardware G06F11/16
• CPC Class Codes: G06F 13/385 for adaptation of a particular data processing system to different peripheral devices
• CPC Class Codes: G06F 13/426 using an embedded synchronisation, e.g. Firewire bus, Fibre Channel bus, SSA bus
• CPC Class Codes: G06F 13/4295 using an embedded synchronisation
• CPC Class Codes: G06F 2213/0042 Universal serial bus [USB]
• CPC Class Codes: G06F 9/4411 Configuring for operating with peripheral devices; Loading of device drivers
• CPC Class Codes: G06F 9/4413 Plug-and-play [PnP]

Abstract

Methods, physical computer-readable media, and devices are provided that allow re-enumeration to be initiated on a USB 3.0-compatible device. The method includes establishing a connection with a host, transmitting an indicator from the device to the host to cause a Link Training and Status State Machine (LTSSM) of the host to move from active state (U0) to one of SS.Inactive and RX.Detect, synchronizing the device with the host, and presenting a new configuration of the device to the host.

Claims

1. A method of initiating re-enumeration of a device compatible with SuperSpeed Universal Serial Bus (USB), the method comprising:

establishing, by the device, a connection with a host over a SuperSpeed USB;

transmitting, by the device, an indicator from the device to the host over the SuperSpeed USB, the indicator being a SuperSpeed indicator identifying a condition of the device that is different than a current condition of the device, the transmitting of the indicator configured to cause a Link Training and Status State Machine (LTSSM) of the host to move from active state (U0) to one of SS.Inactive and RX.Detect in order to induce the host into performing re-enumeration on the device;

when both the host and the device are in the RX.Detect state, synchronizing by the device with the host;

receiving, by the device, a pre-generated device descriptor request from the host; and

presenting, by the device, a new configuration of the device to the host in response to the device descriptor request.

2. The method of claim 1, wherein the step of transmitting the indicator comprises transmitting a corrupt sequence number.

3. The method of claim 1, wherein the device and the host are connected by a universal serial bus (USB) and the step of transmitting the indicator comprises determining whether the USB is idle and preventing LUP transmission, if the USB is idle.

4. The method of claim 1, wherein the step of transmitting the indicator comprises preventing transmission of one or more link commands to the host.

5. The method of claim 4, wherein the one or more link commands include LGOOD and LCRD.

6. The method of claim 1, wherein the step of transmitting the indicator comprises transmitting a signal to the host indicating successful LFPS exit handshake from lower power state U1/U2/U3 to recovery.

7. The method of claim 1, wherein the step of transmitting the indicator comprises sending a signal to the host indicating initiation of recovery without detecting error.

8. A non-transitory computer-readable medium having stored thereon instructions that, when executed by a controller:

cause the device to establish a connection with a host over a SuperSpeed universal serial bus (USB);

cause the device to transmit an indicator from a device to the host over the SuperSpeed USB, the indicator being a SuperSpeed indicator identifying a condition of the device that is different than a current condition of the device, the transmitting of the indicator configured to cause a Link Training and Status State Machine (LTSSM) of the host to move from active state (U0) to one of SS.Inactive and RX.Detect in order to induce the host into performing re-enumeration on the device;

cause the device to synchronize the device with the host when both the host and the device are in the RX.Detect state; and

cause the device to present a new configuration of the device to the host in response to receiving a device descriptor request from the host.

9. The non-transitory computer-readable storage medium of claim 8, wherein:

the device and the host are connected by a universal serial bus (USB); and

the instructions, when executed by the controller, determine whether the USB is idle and preventing upstream link command (LUP) transmission, if the USB is idle.

10. The non-transitory computer-readable storage medium of claim 8, wherein the instructions, when executed by the controller, prevent transmission of one or more link commands to the host.

11. The non-transitory computer-readable storage medium of claim 8, wherein the instructions, when executed by the controller, transmit a signal to the host indicating successful LFPS exit handshake from lower power state U1/U2/U3 to recovery.

12. The non-transitory computer-readable storage medium of claim 8, wherein the instructions, when executed by the controller, send a signal to the host indicating initiation of recovery without detecting error.

13. A device comprising:

a controller; and

a memory in communication with the controller, including instructions, that when executed by the controller;

cause the device to establish a connection between a device and a host over a SuperSpeed universal serial bus (USB), cause the device to transmit an indicator from the device to the host over the SuperSpeed USB, the indicator being a SuperSpeed indicator identifying a condition of the device that is different than a current condition of the device, the transmitting of the indicator configured to cause a Link Training and Status State Machine (LTSSM) of the host to move from active state (U0) to one of SS.Inactive and RX.Detect in order to induce the host into performing re-enumeration with the device, cause the device to synchronize the device with the host when both the host and the device are in the RX.Detect state, and

cause the device to present a new configuration of the device to the host in response to receiving a device descriptor request from the host.

14. The device of claim 13, wherein the memory and the controller are implemented within a single integrated circuit (IC).

15. The device of claim 13, wherein the instructions, when executed by the controller, determine whether a universal serial bus (USB) configured to connect the peripheral device to the host is idle and prevent upstream link command (LUP) transmission, if the USB is idle.

16. The device of claim 13, wherein the instructions, when executed by the controller, prevent transmission of one or more link commands to the host.

17. The device of claim 16, wherein the one or more link commands include LGOOD and LCRD.

18. The device of claim 13, wherein the instructions, when executed by the controller, transmit a signal to the host indicating successful LFPS exit handshake from lower power state U1/U2/U3 to recovery.

19. The device of claim 13, wherein the instructions, when executed by the controller, send a signal to the host indicating initiation of recovery without detecting error.

20. The device of claim 13, wherein the device comprises a SuperSpeed USB device.