/*
   * irq_domain - IRQ translation domains
   *
   * Translation infrastructure between hw and linux irq numbers.  This is
   * helpful for interrupt controllers to implement mapping between hardware
   * irq numbers and the Linux irq number space.
   *
   * irq_domains also have a hook for translating device tree interrupt
   * representation into a hardware irq number that can be mapped back to a
   * Linux irq number without any extra platform support code.
   *
   * irq_domain is expected to be embedded in an interrupt controller's private
   * data structure.
   */
  #ifndef _LINUX_IRQDOMAIN_H
  #define _LINUX_IRQDOMAIN_H
  
  #include <linux/irq.h>

  #include <linux/mod_devicetable.h>

  
  #ifdef CONFIG_IRQ_DOMAIN
  struct device_node;
  struct irq_domain;
  
  /**
   * struct irq_domain_ops - Methods for irq_domain objects
   * @to_irq: (optional) given a local hardware irq number, return the linux
   *          irq number.  If to_irq is not implemented, then the irq_domain
   *          will use this translation: irq = (domain->irq_base + hwirq)
   * @dt_translate: Given a device tree node and interrupt specifier, decode
   *                the hardware irq number and linux irq type value.
   */
  struct irq_domain_ops {
  	unsigned int (*to_irq)(struct irq_domain *d, unsigned long hwirq);
  
  #ifdef CONFIG_OF
  	int (*dt_translate)(struct irq_domain *d, struct device_node *node,
  			    const u32 *intspec, unsigned int intsize,
  			    unsigned long *out_hwirq, unsigned int *out_type);
  #endif /* CONFIG_OF */
  };
  
  /**
   * struct irq_domain - Hardware interrupt number translation object
   * @list: Element in global irq_domain list.
   * @irq_base: Start of irq_desc range assigned to the irq_domain.  The creator
   *            of the irq_domain is responsible for allocating the array of
   *            irq_desc structures.
   * @nr_irq: Number of irqs managed by the irq domain

   * @hwirq_base: Starting number for hwirqs managed by the irq domain

   * @ops: pointer to irq_domain methods
   * @priv: private data pointer for use by owner.  Not touched by irq_domain
   *        core code.
   * @of_node: (optional) Pointer to device tree nodes associated with the
   *           irq_domain.  Used when decoding device tree interrupt specifiers.
   */
  struct irq_domain {
  	struct list_head list;
  	unsigned int irq_base;
  	unsigned int nr_irq;

  	unsigned int hwirq_base;

  	const struct irq_domain_ops *ops;
  	void *priv;
  	struct device_node *of_node;
  };
  
  /**
   * irq_domain_to_irq() - Translate from a hardware irq to a linux irq number
   *
   * Returns the linux irq number associated with a hardware irq.  By default,
   * the mapping is irq == domain->irq_base + hwirq, but this mapping can
   * be overridden if the irq_domain implements a .to_irq() hook.
   */
  static inline unsigned int irq_domain_to_irq(struct irq_domain *d,
  					     unsigned long hwirq)
  {

  	if (d->ops->to_irq)
  		return d->ops->to_irq(d, hwirq);
  	if (WARN_ON(hwirq < d->hwirq_base))
  		return 0;
  	return d->irq_base + hwirq - d->hwirq_base;

  }

  #define irq_domain_for_each_hwirq(d, hw) \
  	for (hw = d->hwirq_base; hw < d->hwirq_base + d->nr_irq; hw++)
  
  #define irq_domain_for_each_irq(d, hw, irq) \
  	for (hw = d->hwirq_base, irq = irq_domain_to_irq(d, hw); \
  	     hw < d->hwirq_base + d->nr_irq; \
  	     hw++, irq = irq_domain_to_irq(d, hw))

  extern void irq_domain_add(struct irq_domain *domain);
  extern void irq_domain_del(struct irq_domain *domain);

  
  extern struct irq_domain_ops irq_domain_simple_ops;

  #endif /* CONFIG_IRQ_DOMAIN */

  #if defined(CONFIG_IRQ_DOMAIN) && defined(CONFIG_OF_IRQ)
  extern void irq_domain_add_simple(struct device_node *controller, int irq_base);
  extern void irq_domain_generate_simple(const struct of_device_id *match,
  					u64 phys_base, unsigned int irq_start);
  #else /* CONFIG_IRQ_DOMAIN && CONFIG_OF_IRQ */
  static inline void irq_domain_generate_simple(const struct of_device_id *match,
  					u64 phys_base, unsigned int irq_start) { }
  #endif /* CONFIG_IRQ_DOMAIN && CONFIG_OF_IRQ */

  #endif /* _LINUX_IRQDOMAIN_H */