[Q] x86 kernel topic

Hi everyone , I own a lenovo k900 running on Intel atom x86 chipset . The phone's battery backup is worst , on tracing I found that the CPU uses most of the power. I tried turning off the hyper threads (detected as 2x cores) the battery lasted ffor 2 ½ hours more in idle state .But when I started camera , the device failed to initialize the camera , so I had to restart the phone .
I want to build a kernel for my device which supports hotplugging and boost the CPU to max only when I initialize camera , games like asphalt 8 runs without lag even when the threads are off .
Can someone help me with this ? Please