来，MTK函数指针的疑问

/*----------------------------------------
Function Pointer: gui_start_timer
Description:      One shot timer
Input Parameters: count    is the delay (Implementation dependent: Normally milliseconds)
               callback is the function that is called when the timer expires
Output Parameters:   none
Returns:       void
Remakrs:       NOTE: DO NOT USE UI TIMER IN CRITICAL CASES
               UI timer will be suspended when LCD backlight is turned off.
----------------------------------------*/

void (*gui_start_timer) (S32 count, void (*callback) (void)) = NULL;