multiple MPU9250  #18

Hi, I want to read the 0x68 and 0x69 alternatively(0x68 , 0x69 ,0x68 ,0x69 .....)
,so i adjust the mympu_open function
from
int mympu_open(unsigned int rate)
to
int mympu_open(unsigned int rate,int device )
(To change the device , the (int device) in the function will be switched between 0 and 1 )
When I put int mympu_open(unsigned int rate,int device ) into loop
, everything goes wrong .i can't read anything anymore !!

How should i do to read alternatively ??

thanks !!