System and method for providing universal serial bus link power management policies in a processor environment

Abstract

One particular example implementation may include an apparatus that includes logic, at least a portion of which is in hardware, the logic configured to: determine that a first device maintains a link to a platform in a selective suspend state; assign a first latency value to the first device; identify at least one user detectable artifact when a second device exits the selective suspend state; and assign, to the second device, a second latency value that is different from the first value.

What is claimed is: 
     
         1 . An apparatus, comprising:
 logic, at least a portion of which is in hardware, the logic configured to:
 determine that a first device maintains a link to a platform in a selective suspend state; 
 assign a first latency value to the first device; 
 identify at least one user detectable artifact when a second device exits the selective suspend state; and 
 assign, to the second device, a second latency value that is different from the first value. 
   
     
     
         2 . The apparatus of  claim 1 , wherein the first latency value is approximately four hundred (400) microseconds (us). 
     
     
         3 . The apparatus of  claim 1 , wherein the second latency value is between approximately three (3) to five (5) milliseconds (ms). 
     
     
         4 . The apparatus of  claim 1 , wherein the first device is a digital camera, a secure digital card reader, or a television tuner. 
     
     
         5 . The apparatus of  claim 1 , wherein the second device is a human interface device. 
     
     
         6 . The apparatus of  claim 1 , wherein the apparatus is further configured to:
 determine that when a third device exits the selective suspend state, the exit causes a buffer overrun or a buffer underrun.   
     
     
         7 . The apparatus of  claim 1 , wherein the first latency value is a Best Effort Service Latency (BESL) value indicative of an attempt to service the first device within a designated time interval. 
     
     
         8 . The apparatus of  claim 1 , wherein the first device includes a buffer and the latency value is dependent on a size of the buffer. 
     
     
         9 . A system, comprising:
 a device controller; and   a platform power management controller, wherein the system is configured for:
 determining that a first device maintains a link in a selective suspend state; 
 assigning a first latency value to the first device; 
 identifying at least one user detectable artifact when a second device exits the selective suspend state; and 
 assigning, to the second device, a second latency value that is different from the first latency value. 
   
     
     
         10 . The system of  claim 9 , wherein the first latency value is approximately four hundred (400) microseconds (us). 
     
     
         11 . The system of  claim 9 , wherein the second latency value is between approximately three (3) to five (5) milliseconds (ms). 
     
     
         12 . The system of  claim 9 , wherein the first device is a digital camera, a secure digital card reader, or a television tuner. 
     
     
         13 . The system of  claim 9 , wherein the second device is a human interface device. 
     
     
         14 . The system of  claim 9 , wherein the system is further configured for:
 determining that when a third device exits the selective suspend state, the exit causes a buffer overrun or a buffer underrun.   
     
     
         15 . The system of  claim 9 , wherein the first latency value is a Best Effort Service Latency (BESL) value indicative of an attempt to service the first device within a designated time interval. 
     
     
         16 . The system of  claim 9 , wherein the first device includes a buffer and the latency value is dependent on a size of the buffer. 
     
     
         17 . A non-transitory computer readable medium comprising instructions that, when executed, cause an apparatus to:
 determine that a first device maintains a link to a platform in a selective suspend state;   assign a first latency value to the first device;   identify at least one user detectable artifact when a second device exits the selective suspend state; and   assign, to the second device, a second latency value that is different from the first value.   
     
     
         18 . The computer readable medium of  claim 17 , wherein the first latency value is approximately four hundred (400) microseconds (us). 
     
     
         19 . The computer readable medium of  claim 17 , wherein the second latency value is between approximately three (3) to about five (5) milliseconds (ms). 
     
     
         20 . The computer readable medium of  claim 17 , wherein the first device is a digital camera, a secure digital card reader, or a television tuner. 
     
     
         21 . The computer readable medium of  claim 17 , wherein the second device is a human interface device. 
     
     
         22 . The computer readable medium of  claim 17 , wherein the apparatus is further configured to:
 determine that when a third device exits the selective suspend state, the exit causes a buffer overrun or a buffer underrun.   
     
     
         23 . The computer readable medium of  claim 17 , wherein the first latency value is a Best Effort Service Latency (BESL) value indicative of an attempt to service the first device within a designated time interval. 
     
     
         24 . The computer readable medium of  claim 17 , wherein the first device includes a buffer and the latency value is dependent on a size of the buffer. 
     
     
         25 . An apparatus, comprising:
 means for determining that a first device maintains a link to a platform in a selective suspend state;   means for assigning a first latency value to the first device;   means for identifying at least one user detectable artifact when a second device exits the selective suspend state; and   means for assigning, to the second device, a second latency value that is different from the first latency value.   
     
     
         26 . The apparatus of  claim 25 , further comprising:
 means for determining that when a third device exits the selective suspend state, the exit causes a buffer overrun or a buffer underrun.   
     
     
         27 . The apparatus of  claim 25 , wherein the second latency value is between approximately three (3) to five (5) milliseconds (ms). 
     
     
         28 . The apparatus of  claim 25 , wherein the first device is a digital camera, a secure digital card reader, or a television tuner. 
     
     
         29 . The apparatus of  claim 25 , wherein the second device is a human interface device. 
     
     
         30 . The apparatus of  claim 25 , wherein the first latency value is a Best Effort Service Latency (BESL) value indicative of an attempt to service the first device within a designated time interval, and wherein the first device includes a buffer and the latency value is dependent on a size of the buffer.