I want to manipulate the voice call data. It seems that the data is handle by the hardware. I try to access it by switching triggers(yet I do not know if related triggers exit) to make the hardware passing audio data to software. After some effort, I find a interface setForceUse() and think it may helps. The second param of this function can be:
AUDIO_POLICY_FORCE_NO_BT_A2DP, /* A2DP sink is not preferred to speaker or wired HS */
Q1:I just want to know the meaning of these params.
Q2:Any suggestions that help to accomplish my task will be appreciated.
I am building my own android ROM. So it is just ok to modify the system source files.