#ifndef __OF_IOMMU_H
  #define __OF_IOMMU_H

  #include <linux/device.h>

  #include <linux/iommu.h>
  #include <linux/of.h>

  #ifdef CONFIG_OF_IOMMU
  
  extern int of_get_dma_window(struct device_node *dn, const char *prefix,
  			     int index, unsigned long *busno, dma_addr_t *addr,
  			     size_t *size);

  extern const struct iommu_ops *of_iommu_configure(struct device *dev,

  					struct device_node *master_np);

  #else
  
  static inline int of_get_dma_window(struct device_node *dn, const char *prefix,
  			    int index, unsigned long *busno, dma_addr_t *addr,
  			    size_t *size)
  {
  	return -EINVAL;
  }

  static inline const struct iommu_ops *of_iommu_configure(struct device *dev,

  					 struct device_node *master_np)

  {
  	return NULL;
  }

  #endif	/* CONFIG_OF_IOMMU */

  void of_iommu_set_ops(struct device_node *np, const struct iommu_ops *ops);
  const struct iommu_ops *of_iommu_get_ops(struct device_node *np);

  
  extern struct of_device_id __iommu_of_table;
  
  typedef int (*of_iommu_init_fn)(struct device_node *);
  
  #define IOMMU_OF_DECLARE(name, compat, fn) \
  	_OF_DECLARE(iommu, name, compat, fn, of_iommu_init_fn)

  #endif /* __OF_IOMMU_H */