TECHNIQUES FOR SEAMLESS TRANSITION BETWEEN HOST DISPLAY AND REMOTE DISPLAY

• US 20200133608A1
• Filed: 10/31/2018
• Published: 04/30/2020
• Est. Priority Date: 10/31/2018
• Status: Active Grant

• Current Assignee: ATI Technologies ULC (Advanced Micro Devices, Inc.)
• Original Assignee: ATI Technologies ULC (Advanced Micro Devices, Inc.)
• Inventors: Liang, Wei, Lei, Jun, Fok, Patrick Pak Kin, Vagiakos, Panagiotis, Cyr, Aric, Zhang, Min
• Granted Patent: US 11,262,964 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 3/14 Digital output to display device ; Cooperation and interconnection of the display device with other functional units
• CPC Class Codes: G06F 3/1423 controlling a plurality of local displays, e.g. CRT and flat panel display
• CPC Class Codes: G06F 3/1454 involving copying of the display data of a local workstation or window to a remote workstation or window so that an actual copy of the data is displayed simultaneously on two or more displays, e.g. teledisplay
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 5/12 Synchronisation between the display unit and other units, e.g. other display units, video-disc players

Abstract

Described herein are techniques for removing control of a display from an operating system. The disclosed techniques decouple operation of the physical display device from control of the operating system so that the display device may be powered down while not needed during streaming. The device driver for the graphics card, into which a display device cable is plugged, simulates operation of the display but allows the display to be powered down. Simulating the display involves properly responding to queries or commands from the operating system, and generating the signals that would be expected from the display device by the operating system. While simulated in this manner, whether the display device is actually powered down does not matter to the operation of an application being streamed, because the operating system still “believes” the display device is powered on. Thus application streaming is not interrupted by powering down the display device.

Claims

1. A method for performing display operations on a device executing an operating system, the method comprising:

detecting a first mode-switch trigger for entering into a display simulation mode;

responsive to the first mode-switch trigger, determining settings for a simulated display;

entering the display simulation mode, in which communication with the operating system regarding display operation occurs according to the simulated display;

detecting a second mode-switch trigger for leaving the display simulation mode; and

responsive to the second mode-switch trigger, leaving the display simulation mode.

2. The method of claim 1, wherein a physical display exists and is connected to the device.

3. The method of claim 2, wherein the simulated display includes cached status and capability data of the physical display.

4. The method of claim 1, wherein no physical display is connected to the device.

5. The method of claim 4, wherein the simulated display includes status and capability data for a virtual display.

6. The method of claim 1, wherein communicating with the operating system regarding display operation according to the simulated display comprises:

transmitting a vertical synchronization signal to the operating system according to the simulated display.

7. The method of claim 1, wherein communicating with the operating system regarding display operation according to the simulated display comprises:

responding to operating system commands to change display state to newly requested display state by updating data of the simulated display to reflect the newly requested display state.

8. The method of claim 1, further comprising:

during the display simulation mode, refraining from transmitting power adjustment notifications received from the display to the operating system.

9. The method of claim 1, wherein the first mode-switch trigger comprises one of starting an application whose data is to be streamed, receiving a user request to initiate the display simulation mode, or detecting initiation of application streaming.

10. A device for performing display operations, the device comprising:

a memory configured to store an operating system and a driver; and

a processor configured to execute the operating system and the driver, wherein when executed, the driver is configured to;

detect a first mode-switch trigger for entering into a display simulation mode;

responsive to the first mode-switch trigger, determine settings for a simulated display;

enter the display simulation mode, in which communication with the operating system regarding display operation occurs according to the simulated display;

detect a second mode-switch trigger for leaving the display simulation mode; and

responsive to the second mode-switch trigger, leave the display simulation mode.

11. The device of claim 10, wherein a physical display device is connected to the device.

12. The device of claim 11, wherein the simulated display includes cached status and capability data of the physical display.

13. The device of claim 10, wherein no physical display is connected to the device.

14. The device of claim 13, wherein the simulated display includes status and capability data for a virtual display.

15. The device of claim 10, wherein communicating with the operating system regarding display operation according to the simulated display comprises:

transmitting a vertical synchronization signal to the operating system according to the simulated display.

16. The device of claim 10, wherein communicating with the operating system regarding display operation according to the simulated display comprises:

responding to operating system commands to change display state to newly requested display state by updating data of the simulated display to reflect the newly requested display state.

17. The device of claim 10, wherein the driver is further configured to:

during the display simulation mode, refrain from transmitting power adjustment notifications received from the display to the operating system.

18. The device of claim 10, wherein the first mode-switch trigger comprises one of starting an application whose data is to be streamed, receiving a user request to initiate the display simulation mode, or detecting initiation of application streaming.

19. A non-transitory computer-readable medium storing instructions that, when executed by a processor, cause the processor to perform display operations on a device executing an operating system, by:

detecting a first mode-switch trigger for entering into a display simulation mode;

responsive to the first mode-switch trigger, determining settings for a simulated display;

entering the display simulation mode, in which communication with the operating system regarding display operation occurs according to the simulated display;

detecting a second mode-switch trigger for leaving the display simulation mode; and

responsive to the second mode-switch trigger, leaving the display simulation mode.

20. The non-transitory computer-readable medium of claim 19, wherein communicating with the operating system regarding display operation according to the simulated display comprises:

transmitting a vertical synchronization signal to the operating system according to the simulated display.