Method and system for a reduced USB polling rate to save power on a bluetooth host
View Patent ↗A Bluetooth host in a normal mode is enabled to monitor activities at USB endpoints. A Bluetooth USB radio has one or more active Bluetooth connections with peer Bluetooth radios. When each of the Bluetooth connections is in sniff mode, the Bluetooth host enables cancellation of normal USB activities at USB endpoints to enter a low power mode. The Bluetooth connections are still alive while the Bluetooth host is in the low power mode. In the low power mode, the Bluetooth host is enabled not to poll the bulk endpoint and to poll a USB interrupt endpoint in extended intervals for Bluetooth data received from the Bluetooth USB radio. The Bluetooth host is enabled to switch from the low power mode to the normal mode to process the received Bluetooth data over the bulk endpoint when a specific HCI event is received over the interrupt endpoint.
1. A system, comprising:
a host processor in a Bluetooth enabled device, the host processor being configured to:
determine whether all active Bluetooth connections of a Bluetooth Universal Serial Bus (USB) radio are in a particular Bluetooth mode of operation, the Bluetooth USB radio having at least one active Bluetooth connection; and
enter a low power mode in response to determining that all of the active Bluetooth connections of the Bluetooth USB radio are in the particular Bluetooth mode of operation.
2. The system of claim 1 , wherein the host processor is configured to enter a normal power mode from the low power mode in response to determining that at least one previously active Bluetooth connection of the Bluetooth USB radio has become disconnected.
3. The system of claim 1 , wherein the host processor is configured to enter a normal power mode from the low power mode in response to determining that at least one active Bluetooth connection of the Bluetooth USB radio has exited the particular Bluetooth mode of operation.
4. The system of claim 1 , wherein the host processor is configured to enter a normal power mode from the low power mode in response to determining that data has been received by the Bluetooth USB radio over at least one active Bluetooth connection.
5. The system of claim 4 , wherein the host processor is configured to:
poll a USB bulk endpoint of the Bluetooth USB radio, subsequently to entering the normal power mode from the low power mode, for the data that has been received by the Bluetooth USB radio over the at least one active Bluetooth connection;
obtain, over the USB bulk endpoint, the data that has been received by the Bluetooth USB radio over the at least one active Bluetooth connection; and
process the data obtained over the USB bulk endpoint.
6. The system of claim 1 , wherein the particular Bluetooth mode of operation is a Bluetooth sniff mode.
7. The system of claim 1 , wherein the host processor is further configured to cancel normal USB activities of at least one USB endpoint of the Bluetooth USB radio in response to determining that all of the active Bluetooth connections of the Bluetooth USB radio are in the particular Bluetooth mode of operation.
8. The system of claim 1 , wherein the low power mode is selected from the group consisting of: a sleep mode, a deep sleep mode, and a deeper sleep mode.
9. The system of claim 1 , wherein, in response to entering the low power mode, the host processor is configured not to poll a USB bulk endpoint of the Bluetooth USB radio.
10. The system of claim 1 , wherein, in response to entering the low power mode, the host processor is configured to poll a USB interrupt endpoint of the Bluetooth USB radio at extended polling intervals.
11. A method, comprising the steps of:
determining, by a host processor in a Bluetooth enabled device, whether all active Bluetooth connections of a Bluetooth Universal Serial Bus (USB) radio are in a particular Bluetooth mode of operation, the Bluetooth USB radio having at least one active Bluetooth connection; and
entering a low power mode by the host processor in response to determining that all of the active Bluetooth connections of the Bluetooth USB radio are in the particular Bluetooth mode of operation.
12. The method of claim 11 , further comprising the step of entering a normal power mode from the low power mode by the host processor in response to determining that at least one previously active Bluetooth connection of the Bluetooth USB radio has become disconnected.
13. The method of claim 11 , further comprising the step of entering a normal power mode from the low power mode by the host processor in response to determining that at least one active Bluetooth connection of the Bluetooth USB radio has exited the particular Bluetooth mode of operation.
14. The method of claim 11 , further comprising the step of entering a normal power mode from the low power mode by the host processor in response to determining that data has been received by the Bluetooth USB radio over at least one active Bluetooth connection.
15. The method of claim 14 , further comprising the steps of:
polling a USB bulk endpoint of the Bluetooth USB radio by the host processor, subsequently to entering the normal power mode from the low power mode, for the data that has been received by the Bluetooth USB radio over the at least one active Bluetooth connection;
obtaining, over the USB bulk endpoint by the host processor, the data that has been received by the Bluetooth USB radio over the at least one active Bluetooth connection; and
processing by the host processor the data obtained over the USB bulk endpoint.
16. The method of claim 11 , wherein the particular Bluetooth mode of operation is a Bluetooth sniff mode.
17. The method of claim 11 , further comprising the step of cancelling by the host processor normal USB activities of at least one USB endpoint of the Bluetooth USB radio in response to determining that all of the active Bluetooth connections of the Bluetooth USB radio are in the particular Bluetooth mode of operation.
18. The method of claim 11 , wherein, in response to entering the low power mode, the host processor is configured not to poll a USB bulk endpoint of the Bluetooth USB radio.
19. The method of claim 11 , wherein, in response to entering the low power mode, the host processor is configured to poll a USB interrupt endpoint of the Bluetooth USB radio at extended polling intervals.
20. A system, comprising:
means for determining in a Bluetooth enabled device, whether all active Bluetooth connections of a Bluetooth Universal Serial Bus (USB) radio are in a particular Bluetooth mode of operation, the Bluetooth USB radio having at least one active Bluetooth connection; and
means for entering a low power mode by a host processor in response to determining that all of the active Bluetooth connections of the Bluetooth USB radio are in the particular Bluetooth mode of operation.