linux下面的spi用户态程序，非常实用，使得程序员不必编写内核驱动，使用该驱动能够易于spi驱动debug-The following user mode linux spi procedures, very practical, so that programmers do not have to write a kernel driver, use the drive can be easily spi driver debug etc.

该程序用于调试ACPICA中cache实现的问题。-ACPICA has its own cached object implementation. This mechanism is not used by Linux kernel. We have a userspace utility to debug issues in it.