#ifndef _LINUX_DMA_DIRECTION_H
  #define _LINUX_DMA_DIRECTION_H
  /*
   * These definitions mirror those in pci.h, so they can be used
   * interchangeably with their PCI_ counterparts.
   */
  enum dma_data_direction {
  	DMA_BIDIRECTIONAL = 0,
  	DMA_TO_DEVICE = 1,
  	DMA_FROM_DEVICE = 2,
  	DMA_NONE = 3,
  };
  #endif