CC2340R5: How to do shutdown and wake up from shutdown by i/o

Tool/software:

Hi,

             Currently I am working on basic_ble central profile project. I have to use Power_shutdown(0,0); and for the wake up I want to use 3 GPIO(button) which already used for the scanning, connection and data sending.

I have referred an TI forum thread : https://e2e.ti.com/support/wireless-connectivity/bluetooth-group/bluetooth/f/bluetooth-forum/1255184/lp-em-cc2340r5-how-to-know-wake-up-mode-from-power-on-or-shutdown

Can you guide where to call the  Power_registerNotify callback and  to know which I/O has pressed for wakeup and whether its possible to know that for wakeup pressed  button interrupt time (Like 100 millisecond or 200 millisecond).   

I have added an code to enter an shutdown mode 

void Low_Power()
{
    /************************Disable Peripherals*********************************************************************/

    UART2_write(uart,"\nLow power",10, 0);
    UART2_close(uart) ;
    /**********************************************GPIO PIN Enable interrupts *******************************************************/
     GPIO_setConfig(ENGINE_START_BUTTON, GPIO_CFG_IN_NOPULL | GPIO_CFG_SHUTDOWN_WAKE_LOW);
     GPIO_setConfig(LEAD_ME_BUTTON,      GPIO_CFG_IN_NOPULL | GPIO_CFG_SHUTDOWN_WAKE_LOW);
     GPIO_setConfig(ENGINE_STOP_BUTTON,  GPIO_CFG_IN_NOPULL | GPIO_CFG_SHUTDOWN_WAKE_LOW);

   int_fast16_t  Status = PowerCC23X0_notify(PowerLPF3_ENTERING_SHUTDOWN);
   
   if(Status == Power_SOK)
   {       
       Power_shutdown(0,0);
   }
   else
   {
       UART2_write(uart,"\nFAIL",5, 0);
   }

}

How can I implement this please suggest me with any example code regarding implementation of Power_registerNotify callback and PowerLPF3_getResetReason() function.

SDK Version : simplelink_lowpower_f3_sdk_7_40_00_64

CCS version: CCS 12.5.0

Thanks,

Vignesh.