#ifndef _LINUX_IRQ_H
  #define _LINUX_IRQ_H

  
  /*
   * Please do not include this file in generic code.  There is currently
   * no requirement for any architecture to implement anything held
   * within this file.
   *
   * Thanks. --rmk
   */

  #include <linux/smp.h>

  #ifndef CONFIG_S390

  
  #include <linux/linkage.h>
  #include <linux/cache.h>
  #include <linux/spinlock.h>
  #include <linux/cpumask.h>

  #include <linux/irqreturn.h>

  #include <linux/errno.h>

  
  #include <asm/irq.h>
  #include <asm/ptrace.h>

  #include <asm/irq_regs.h>

  struct irq_desc;
  typedef	void fastcall (*irq_flow_handler_t)(unsigned int irq,

  					    struct irq_desc *desc);

  /*
   * IRQ line status.

   *

   * Bits 0-7 are reserved for the IRQF_* bits in linux/interrupt.h

   *
   * IRQ types

   */

  #define IRQ_TYPE_NONE		0x00000000	/* Default, unspecified type */
  #define IRQ_TYPE_EDGE_RISING	0x00000001	/* Edge rising type */
  #define IRQ_TYPE_EDGE_FALLING	0x00000002	/* Edge falling type */
  #define IRQ_TYPE_EDGE_BOTH (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING)
  #define IRQ_TYPE_LEVEL_HIGH	0x00000004	/* Level high type */
  #define IRQ_TYPE_LEVEL_LOW	0x00000008	/* Level low type */
  #define IRQ_TYPE_SENSE_MASK	0x0000000f	/* Mask of the above */
  #define IRQ_TYPE_PROBE		0x00000010	/* Probing in progress */
  
  /* Internal flags */

  #define IRQ_INPROGRESS		0x00000100	/* IRQ handler active - do not enter! */
  #define IRQ_DISABLED		0x00000200	/* IRQ disabled - do not enter! */
  #define IRQ_PENDING		0x00000400	/* IRQ pending - replay on enable */
  #define IRQ_REPLAY		0x00000800	/* IRQ has been replayed but not acked yet */
  #define IRQ_AUTODETECT		0x00001000	/* IRQ is being autodetected */
  #define IRQ_WAITING		0x00002000	/* IRQ not yet seen - for autodetection */
  #define IRQ_LEVEL		0x00004000	/* IRQ level triggered */
  #define IRQ_MASKED		0x00008000	/* IRQ masked - shouldn't be seen again */
  #define IRQ_PER_CPU		0x00010000	/* IRQ is per CPU */
  #define IRQ_NOPROBE		0x00020000	/* IRQ is not valid for probing */
  #define IRQ_NOREQUEST		0x00040000	/* IRQ cannot be requested */
  #define IRQ_NOAUTOEN		0x00080000	/* IRQ will not be enabled on request irq */

  #define IRQ_WAKEUP		0x00100000	/* IRQ triggers system wakeup */
  #define IRQ_MOVE_PENDING	0x00200000	/* need to re-target IRQ destination */
  #define IRQ_NO_BALANCING	0x00400000	/* IRQ is excluded from balancing */

  #ifdef CONFIG_IRQ_PER_CPU

  # define CHECK_IRQ_PER_CPU(var) ((var) & IRQ_PER_CPU)

  # define IRQ_NO_BALANCING_MASK	(IRQ_PER_CPU | IRQ_NO_BALANCING)

  #else
  # define CHECK_IRQ_PER_CPU(var) 0

  # define IRQ_NO_BALANCING_MASK	IRQ_NO_BALANCING

  #endif

  struct proc_dir_entry;

  struct msi_desc;

  /**

   * struct irq_chip - hardware interrupt chip descriptor

   *
   * @name:		name for /proc/interrupts
   * @startup:		start up the interrupt (defaults to ->enable if NULL)
   * @shutdown:		shut down the interrupt (defaults to ->disable if NULL)
   * @enable:		enable the interrupt (defaults to chip->unmask if NULL)
   * @disable:		disable the interrupt (defaults to chip->mask if NULL)

   * @ack:		start of a new interrupt
   * @mask:		mask an interrupt source
   * @mask_ack:		ack and mask an interrupt source
   * @unmask:		unmask an interrupt source

   * @eoi:		end of interrupt - chip level
   * @end:		end of interrupt - flow level

   * @set_affinity:	set the CPU affinity on SMP machines
   * @retrigger:		resend an IRQ to the CPU
   * @set_type:		set the flow type (IRQ_TYPE_LEVEL/etc.) of an IRQ
   * @set_wake:		enable/disable power-management wake-on of an IRQ
   *
   * @release:		release function solely used by UML

   * @typename:		obsoleted by name, kept as migration helper

   */

  struct irq_chip {
  	const char	*name;

  	unsigned int	(*startup)(unsigned int irq);
  	void		(*shutdown)(unsigned int irq);
  	void		(*enable)(unsigned int irq);
  	void		(*disable)(unsigned int irq);

  	void		(*ack)(unsigned int irq);

  	void		(*mask)(unsigned int irq);
  	void		(*mask_ack)(unsigned int irq);
  	void		(*unmask)(unsigned int irq);

  	void		(*eoi)(unsigned int irq);

  	void		(*end)(unsigned int irq);
  	void		(*set_affinity)(unsigned int irq, cpumask_t dest);

  	int		(*retrigger)(unsigned int irq);

  	int		(*set_type)(unsigned int irq, unsigned int flow_type);
  	int		(*set_wake)(unsigned int irq, unsigned int on);

  	/* Currently used only by UML, might disappear one day.*/
  #ifdef CONFIG_IRQ_RELEASE_METHOD

  	void		(*release)(unsigned int irq, void *dev_id);

  #endif

  	/*
  	 * For compatibility, ->typename is copied into ->name.
  	 * Will disappear.
  	 */
  	const char	*typename;

  };

  /**
   * struct irq_desc - interrupt descriptor
   *

   * @handle_irq:		highlevel irq-events handler [if NULL, __do_IRQ()]
   * @chip:		low level interrupt hardware access

   * @msi_desc:		MSI descriptor

   * @handler_data:	per-IRQ data for the irq_chip methods
   * @chip_data:		platform-specific per-chip private data for the chip
   *			methods, to allow shared chip implementations

   * @action:		the irq action chain
   * @status:		status information
   * @depth:		disable-depth, for nested irq_disable() calls

   * @wake_depth:		enable depth, for multiple set_irq_wake() callers

   * @irq_count:		stats field to detect stalled irqs
   * @irqs_unhandled:	stats field for spurious unhandled interrupts
   * @lock:		locking for SMP
   * @affinity:		IRQ affinity on SMP

   * @cpu:		cpu index useful for balancing

   * @pending_mask:	pending rebalanced interrupts

   * @dir:		/proc/irq/ procfs entry
   * @affinity_entry:	/proc/irq/smp_affinity procfs entry on SMP

   * @name:		flow handler name for /proc/interrupts output

   */

  struct irq_desc {

  	irq_flow_handler_t	handle_irq;

  	struct irq_chip		*chip;

  	struct msi_desc		*msi_desc;

  	void			*handler_data;

  	void			*chip_data;
  	struct irqaction	*action;	/* IRQ action list */
  	unsigned int		status;		/* IRQ status */

  	unsigned int		depth;		/* nested irq disables */

  	unsigned int		wake_depth;	/* nested wake enables */

  	unsigned int		irq_count;	/* For detecting broken IRQs */
  	unsigned int		irqs_unhandled;

  	unsigned long		last_unhandled;	/* Aging timer for unhandled count */

  	spinlock_t		lock;

  #ifdef CONFIG_SMP

  	cpumask_t		affinity;

  	unsigned int		cpu;

  #endif

  #if defined(CONFIG_GENERIC_PENDING_IRQ) || defined(CONFIG_IRQBALANCE)

  	cpumask_t		pending_mask;

  #endif

  #ifdef CONFIG_PROC_FS

  	struct proc_dir_entry	*dir;

  #endif

  	const char		*name;

  } ____cacheline_internodealigned_in_smp;

  extern struct irq_desc irq_desc[NR_IRQS];

  /*
   * Migration helpers for obsolete names, they will go away:
   */

  #define hw_interrupt_type	irq_chip
  typedef struct irq_chip		hw_irq_controller;
  #define no_irq_type		no_irq_chip

  typedef struct irq_desc		irq_desc_t;
  
  /*
   * Pick up the arch-dependent methods:
   */
  #include <asm/hw_irq.h>

  extern int setup_irq(unsigned int irq, struct irqaction *new);

  
  #ifdef CONFIG_GENERIC_HARDIRQS

  #ifndef handle_dynamic_tick
  # define handle_dynamic_tick(a)		do { } while (0)
  #endif

  #ifdef CONFIG_SMP

  #if defined(CONFIG_GENERIC_PENDING_IRQ) || defined(CONFIG_IRQBALANCE)

  void set_pending_irq(unsigned int irq, cpumask_t mask);
  void move_native_irq(int irq);

  void move_masked_irq(int irq);

  #else /* CONFIG_GENERIC_PENDING_IRQ || CONFIG_IRQBALANCE */
  
  static inline void move_irq(int irq)
  {
  }
  
  static inline void move_native_irq(int irq)
  {
  }

  static inline void move_masked_irq(int irq)
  {
  }

  static inline void set_pending_irq(unsigned int irq, cpumask_t mask)
  {
  }

  #endif /* CONFIG_GENERIC_PENDING_IRQ */

  extern int irq_set_affinity(unsigned int irq, cpumask_t cpumask);
  extern int irq_can_set_affinity(unsigned int irq);

  #else /* CONFIG_SMP */

  #define move_native_irq(x)

  #define move_masked_irq(x)

  static inline int irq_set_affinity(unsigned int irq, cpumask_t cpumask)
  {
  	return -EINVAL;
  }
  
  static inline int irq_can_set_affinity(unsigned int irq) { return 0; }

  #endif /* CONFIG_SMP */

  #ifdef CONFIG_IRQBALANCE
  extern void set_balance_irq_affinity(unsigned int irq, cpumask_t mask);
  #else
  static inline void set_balance_irq_affinity(unsigned int irq, cpumask_t mask)
  {
  }
  #endif

  #ifdef CONFIG_AUTO_IRQ_AFFINITY
  extern int select_smp_affinity(unsigned int irq);
  #else
  static inline int select_smp_affinity(unsigned int irq)
  {
  	return 1;
  }
  #endif

  extern int no_irq_affinity;

  static inline int irq_balancing_disabled(unsigned int irq)
  {
  	return irq_desc[irq].status & IRQ_NO_BALANCING_MASK;
  }

  /* Handle irq action chains: */

  extern int handle_IRQ_event(unsigned int irq, struct irqaction *action);

  
  /*
   * Built-in IRQ handlers for various IRQ types,
   * callable via desc->chip->handle_irq()
   */

  extern void fastcall handle_level_irq(unsigned int irq, struct irq_desc *desc);
  extern void fastcall handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc);
  extern void fastcall handle_edge_irq(unsigned int irq, struct irq_desc *desc);
  extern void fastcall handle_simple_irq(unsigned int irq, struct irq_desc *desc);
  extern void fastcall handle_percpu_irq(unsigned int irq, struct irq_desc *desc);
  extern void fastcall handle_bad_irq(unsigned int irq, struct irq_desc *desc);

  
  /*

   * Monolithic do_IRQ implementation.
   * (is an explicit fastcall, because i386 4KSTACKS calls it from assembly)

   */

  #ifndef CONFIG_GENERIC_HARDIRQS_NO__DO_IRQ

  extern fastcall unsigned int __do_IRQ(unsigned int irq);

  #endif

  /*
   * Architectures call this to let the generic IRQ layer
   * handle an interrupt. If the descriptor is attached to an
   * irqchip-style controller then we call the ->handle_irq() handler,
   * and it calls __do_IRQ() if it's attached to an irqtype-style controller.
   */

  static inline void generic_handle_irq(unsigned int irq)

  {
  	struct irq_desc *desc = irq_desc + irq;

  #ifdef CONFIG_GENERIC_HARDIRQS_NO__DO_IRQ

  	desc->handle_irq(irq, desc);

  #else

  	if (likely(desc->handle_irq))

  		desc->handle_irq(irq, desc);

  	else

  		__do_IRQ(irq);

  #endif

  }

  /* Handling of unhandled and spurious interrupts: */

  extern void note_interrupt(unsigned int irq, struct irq_desc *desc,

  			   int action_ret);

  /* Resending of interrupts :*/
  void check_irq_resend(struct irq_desc *desc, unsigned int irq);

  /* Enable/disable irq debugging output: */
  extern int noirqdebug_setup(char *str);
  
  /* Checks whether the interrupt can be requested by request_irq(): */
  extern int can_request_irq(unsigned int irq, unsigned long irqflags);

  /* Dummy irq-chip implementations: */

  extern struct irq_chip no_irq_chip;

  extern struct irq_chip dummy_irq_chip;

  
  extern void

  set_irq_chip_and_handler(unsigned int irq, struct irq_chip *chip,
  			 irq_flow_handler_t handle);
  extern void

  set_irq_chip_and_handler_name(unsigned int irq, struct irq_chip *chip,
  			      irq_flow_handler_t handle, const char *name);

  extern void

  __set_irq_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
  		  const char *name);

  /*
   * Set a highlevel flow handler for a given IRQ:
   */
  static inline void

  set_irq_handler(unsigned int irq, irq_flow_handler_t handle)

  {

  	__set_irq_handler(irq, handle, 0, NULL);

  }
  
  /*
   * Set a highlevel chained flow handler for a given IRQ.
   * (a chained handler is automatically enabled and set to
   *  IRQ_NOREQUEST and IRQ_NOPROBE)
   */
  static inline void
  set_irq_chained_handler(unsigned int irq,

  			irq_flow_handler_t handle)

  {

  	__set_irq_handler(irq, handle, 1, NULL);

  }

  /* Handle dynamic irq creation and destruction */
  extern int create_irq(void);
  extern void destroy_irq(unsigned int irq);

  /* Test to see if a driver has successfully requested an irq */
  static inline int irq_has_action(unsigned int irq)
  {
  	struct irq_desc *desc = irq_desc + irq;
  	return desc->action != NULL;
  }

  /* Dynamic irq helper functions */
  extern void dynamic_irq_init(unsigned int irq);
  extern void dynamic_irq_cleanup(unsigned int irq);

  /* Set/get chip/data for an IRQ: */

  extern int set_irq_chip(unsigned int irq, struct irq_chip *chip);
  extern int set_irq_data(unsigned int irq, void *data);
  extern int set_irq_chip_data(unsigned int irq, void *data);
  extern int set_irq_type(unsigned int irq, unsigned int type);

  extern int set_irq_msi(unsigned int irq, struct msi_desc *entry);

  
  #define get_irq_chip(irq)	(irq_desc[irq].chip)
  #define get_irq_chip_data(irq)	(irq_desc[irq].chip_data)
  #define get_irq_data(irq)	(irq_desc[irq].handler_data)

  #define get_irq_msi(irq)	(irq_desc[irq].msi_desc)

  #endif /* CONFIG_GENERIC_HARDIRQS */

  #endif /* !CONFIG_S390 */

  #endif /* _LINUX_IRQ_H */