include/linux/irq.h - maze/linux - Git at Google

 #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/gfp.h>
 #include <linux/irqreturn.h>
 #include <linux/irqnr.h>
 #include <linux/errno.h>
 #include <linux/topology.h>
 #include <linux/wait.h>

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

 struct irq_desc;
 typedef	void (*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 */

 #ifndef CONFIG_GENERIC_HARDIRQS_NO_COMPAT
 #define IRQ_INPROGRESS		0x00000100	/* DEPRECATED */
 #define IRQ_REPLAY		0x00000200	/* DEPRECATED */
 #define IRQ_WAITING		0x00000400	/* DEPRECATED */
 #define IRQ_DISABLED		0x00000800	/* DEPRECATED */
 #define IRQ_PENDING		0x00001000	/* DEPRECATED */
 #define IRQ_MASKED		0x00002000	/* DEPRECATED */
 /* DEPRECATED use irq_setaffinity_pending() instead*/
 #define IRQ_MOVE_PENDING	0x00004000
 #endif

 #define IRQ_LEVEL		0x00008000	/* IRQ level triggered */
 #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_NO_BALANCING	0x00400000	/* IRQ is excluded from balancing */
 #define IRQ_MOVE_PCNTXT		0x01000000	/* IRQ migration from process context */
 #define IRQ_AFFINITY_SET	0x02000000	/* IRQ affinity was set from userspace*/
 #define IRQ_NESTED_THREAD	0x10000000	/* IRQ is nested into another, no own handler thread */

 #define IRQF_MODIFY_MASK	\
 	(IRQ_TYPE_SENSE_MASK | IRQ_NOPROBE | IRQ_NOREQUEST | \
 	 IRQ_NOAUTOEN | IRQ_MOVE_PCNTXT | IRQ_LEVEL | IRQ_NO_BALANCING | \
 	 IRQ_PER_CPU | IRQ_NESTED_THREAD)

 #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

 /*
  * Return value for chip->irq_set_affinity()
  *
  * IRQ_SET_MASK_OK	- OK, core updates irq_data.affinity
  * IRQ_SET_MASK_NOCPY	- OK, chip did update irq_data.affinity
  */
 enum {
 	IRQ_SET_MASK_OK = 0,
 	IRQ_SET_MASK_OK_NOCOPY,
 };

 struct msi_desc;

 /**
  * struct irq_data - per irq and irq chip data passed down to chip functions
  * @irq:		interrupt number
  * @node:		node index useful for balancing
  * @state_use_accessor: status information for irq chip functions.
  *			Use accessor functions to deal with it
  * @chip:		low level interrupt hardware access
  * @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
  * @msi_desc:		MSI descriptor
  * @affinity:		IRQ affinity on SMP
  *
  * The fields here need to overlay the ones in irq_desc until we
  * cleaned up the direct references and switched everything over to
  * irq_data.
  */
 struct irq_data {
 	unsigned int		irq;
 	unsigned int		node;
 	unsigned int		state_use_accessors;
 	struct irq_chip		*chip;
 	void			*handler_data;
 	void			*chip_data;
 	struct msi_desc		*msi_desc;
 #ifdef CONFIG_SMP
 	cpumask_var_t		affinity;
 #endif
 };

 /*
  * Bit masks for irq_data.state
  *
  * IRQD_SETAFFINITY_PENDING	- Affinity setting is pending
  */
 enum {
 	/* Bit 0 - 7 reserved for TYPE will use later */
 	IRQD_SETAFFINITY_PENDING = (1 << 8),
 };

 static inline bool irqd_is_setaffinity_pending(struct irq_data *d)
 {
 	return d->state_use_accessors & IRQD_SETAFFINITY_PENDING;
 }

 /**
  * struct irq_chip - hardware interrupt chip descriptor
  *
  * @name:		name for /proc/interrupts
  * @startup:		deprecated, replaced by irq_startup
  * @shutdown:		deprecated, replaced by irq_shutdown
  * @enable:		deprecated, replaced by irq_enable
  * @disable:		deprecated, replaced by irq_disable
  * @ack:		deprecated, replaced by irq_ack
  * @mask:		deprecated, replaced by irq_mask
  * @mask_ack:		deprecated, replaced by irq_mask_ack
  * @unmask:		deprecated, replaced by irq_unmask
  * @eoi:		deprecated, replaced by irq_eoi
  * @end:		deprecated, will go away with __do_IRQ()
  * @set_affinity:	deprecated, replaced by irq_set_affinity
  * @retrigger:		deprecated, replaced by irq_retrigger
  * @set_type:		deprecated, replaced by irq_set_type
  * @set_wake:		deprecated, replaced by irq_wake
  * @bus_lock:		deprecated, replaced by irq_bus_lock
  * @bus_sync_unlock:	deprecated, replaced by irq_bus_sync_unlock
  *
  * @irq_startup:	start up the interrupt (defaults to ->enable if NULL)
  * @irq_shutdown:	shut down the interrupt (defaults to ->disable if NULL)
  * @irq_enable:		enable the interrupt (defaults to chip->unmask if NULL)
  * @irq_disable:	disable the interrupt
  * @irq_ack:		start of a new interrupt
  * @irq_mask:		mask an interrupt source
  * @irq_mask_ack:	ack and mask an interrupt source
  * @irq_unmask:		unmask an interrupt source
  * @irq_eoi:		end of interrupt
  * @irq_set_affinity:	set the CPU affinity on SMP machines
  * @irq_retrigger:	resend an IRQ to the CPU
  * @irq_set_type:	set the flow type (IRQ_TYPE_LEVEL/etc.) of an IRQ
  * @irq_set_wake:	enable/disable power-management wake-on of an IRQ
  * @irq_bus_lock:	function to lock access to slow bus (i2c) chips
  * @irq_bus_sync_unlock:function to sync and unlock slow bus (i2c) chips
  *
  * @release:		release function solely used by UML
  */
 struct irq_chip {
 	const char	*name;
 #ifndef CONFIG_GENERIC_HARDIRQS_NO_DEPRECATED
 	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);
 	int		(*set_affinity)(unsigned int irq,
 					const struct cpumask *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);

 	void		(*bus_lock)(unsigned int irq);
 	void		(*bus_sync_unlock)(unsigned int irq);
 #endif
 	unsigned int	(*irq_startup)(struct irq_data *data);
 	void		(*irq_shutdown)(struct irq_data *data);
 	void		(*irq_enable)(struct irq_data *data);
 	void		(*irq_disable)(struct irq_data *data);

 	void		(*irq_ack)(struct irq_data *data);
 	void		(*irq_mask)(struct irq_data *data);
 	void		(*irq_mask_ack)(struct irq_data *data);
 	void		(*irq_unmask)(struct irq_data *data);
 	void		(*irq_eoi)(struct irq_data *data);

 	int		(*irq_set_affinity)(struct irq_data *data, const struct cpumask *dest, bool force);
 	int		(*irq_retrigger)(struct irq_data *data);
 	int		(*irq_set_type)(struct irq_data *data, unsigned int flow_type);
 	int		(*irq_set_wake)(struct irq_data *data, unsigned int on);

 	void		(*irq_bus_lock)(struct irq_data *data);
 	void		(*irq_bus_sync_unlock)(struct irq_data *data);

 	/* Currently used only by UML, might disappear one day.*/
 #ifdef CONFIG_IRQ_RELEASE_METHOD
 	void		(*release)(unsigned int irq, void *dev_id);
 #endif
 };

 /* This include will go away once we isolated irq_desc usage to core code */
 #include <linux/irqdesc.h>

 /*
  * Pick up the arch-dependent methods:
  */
 #include <asm/hw_irq.h>

 #ifndef NR_IRQS_LEGACY
 # define NR_IRQS_LEGACY 0
 #endif

 #ifndef ARCH_IRQ_INIT_FLAGS
 # define ARCH_IRQ_INIT_FLAGS	0
 #endif

 #define IRQ_DEFAULT_INIT_FLAGS	ARCH_IRQ_INIT_FLAGS

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

 #ifdef CONFIG_GENERIC_HARDIRQS

 #if defined(CONFIG_SMP) && defined(CONFIG_GENERIC_PENDING_IRQ)
 void move_native_irq(int irq);
 void move_masked_irq(int irq);
 #else
 static inline void move_native_irq(int irq) { }
 static inline void move_masked_irq(int irq) { }
 #endif

 extern int no_irq_affinity;

 /* Handle irq action chains: */
 extern irqreturn_t handle_IRQ_event(unsigned int irq, struct irqaction *action);

 /*
  * Built-in IRQ handlers for various IRQ types,
  * callable via desc->handle_irq()
  */
 extern void handle_level_irq(unsigned int irq, struct irq_desc *desc);
 extern void handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc);
 extern void handle_edge_irq(unsigned int irq, struct irq_desc *desc);
 extern void handle_simple_irq(unsigned int irq, struct irq_desc *desc);
 extern void handle_percpu_irq(unsigned int irq, struct irq_desc *desc);
 extern void handle_bad_irq(unsigned int irq, struct irq_desc *desc);
 extern void handle_nested_irq(unsigned int irq);

 /* Handling of unhandled and spurious interrupts: */
 extern void note_interrupt(unsigned int irq, struct irq_desc *desc,
 			   irqreturn_t action_ret);


 /* 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);
 }

 void irq_modify_status(unsigned int irq, unsigned long clr, unsigned long set);

 static inline void irq_set_status_flags(unsigned int irq, unsigned long set)
 {
 	irq_modify_status(irq, 0, set);
 }

 static inline void irq_clear_status_flags(unsigned int irq, unsigned long clr)
 {
 	irq_modify_status(irq, clr, 0);
 }

 static inline void irq_set_noprobe(unsigned int irq)
 {
 	irq_modify_status(irq, 0, IRQ_NOPROBE);
 }

 static inline void irq_set_probe(unsigned int irq)
 {
 	irq_modify_status(irq, IRQ_NOPROBE, 0);
 }

 static inline void irq_set_nested_thread(unsigned int irq, bool nest)
 {
 	if (nest)
 		irq_set_status_flags(irq, IRQ_NESTED_THREAD);
 	else
 		irq_clear_status_flags(irq, IRQ_NESTED_THREAD);
 }

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

 /*
  * Dynamic irq helper functions. Obsolete. Use irq_alloc_desc* and
  * irq_free_desc instead.
  */
 extern void dynamic_irq_cleanup(unsigned int irq);
 static inline void dynamic_irq_init(unsigned int irq)
 {
 	dynamic_irq_cleanup(irq);
 }

 /* Set/get chip/data for an IRQ: */
 extern int irq_set_chip(unsigned int irq, struct irq_chip *chip);
 extern int irq_set_handler_data(unsigned int irq, void *data);
 extern int irq_set_chip_data(unsigned int irq, void *data);
 extern int irq_set_irq_type(unsigned int irq, unsigned int type);
 extern int irq_set_msi_desc(unsigned int irq, struct msi_desc *entry);
 extern struct irq_data *irq_get_irq_data(unsigned int irq);

 static inline struct irq_chip *irq_get_chip(unsigned int irq)
 {
 	struct irq_data *d = irq_get_irq_data(irq);
 	return d ? d->chip : NULL;
 }

 static inline struct irq_chip *irq_data_get_irq_chip(struct irq_data *d)
 {
 	return d->chip;
 }

 static inline void *irq_get_chip_data(unsigned int irq)
 {
 	struct irq_data *d = irq_get_irq_data(irq);
 	return d ? d->chip_data : NULL;
 }

 static inline void *irq_data_get_irq_chip_data(struct irq_data *d)
 {
 	return d->chip_data;
 }

 static inline void *irq_get_handler_data(unsigned int irq)
 {
 	struct irq_data *d = irq_get_irq_data(irq);
 	return d ? d->handler_data : NULL;
 }

 static inline void *irq_data_get_irq_handler_data(struct irq_data *d)
 {
 	return d->handler_data;
 }

 static inline struct msi_desc *irq_get_msi_desc(unsigned int irq)
 {
 	struct irq_data *d = irq_get_irq_data(irq);
 	return d ? d->msi_desc : NULL;
 }

 static inline struct msi_desc *irq_data_get_msi(struct irq_data *d)
 {
 	return d->msi_desc;
 }

 #ifndef CONFIG_GENERIC_HARDIRQS_NO_COMPAT
 /* Please do not use: Use the replacement functions instead */
 static inline int set_irq_chip(unsigned int irq, struct irq_chip *chip)
 {
 	return irq_set_chip(irq, chip);
 }
 static inline int set_irq_data(unsigned int irq, void *data)
 {
 	return irq_set_handler_data(irq, data);
 }
 static inline int set_irq_chip_data(unsigned int irq, void *data)
 {
 	return irq_set_chip_data(irq, data);
 }
 static inline int set_irq_type(unsigned int irq, unsigned int type)
 {
 	return irq_set_irq_type(irq, type);
 }
 static inline int set_irq_msi(unsigned int irq, struct msi_desc *entry)
 {
 	return irq_set_msi_desc(irq, entry);
 }
 static inline struct irq_chip *get_irq_chip(unsigned int irq)
 {
 	return irq_get_chip(irq);
 }
 static inline void *get_irq_chip_data(unsigned int irq)
 {
 	return irq_get_chip_data(irq);
 }
 static inline void *get_irq_data(unsigned int irq)
 {
 	return irq_get_handler_data(irq);
 }
 static inline void *irq_data_get_irq_data(struct irq_data *d)
 {
 	return irq_data_get_irq_handler_data(d);
 }
 static inline struct msi_desc *get_irq_msi(unsigned int irq)
 {
 	return irq_get_msi_desc(irq);
 }
 static inline void set_irq_noprobe(unsigned int irq)
 {
 	irq_set_noprobe(irq);
 }
 static inline void set_irq_probe(unsigned int irq)
 {
 	irq_set_probe(irq);
 }
 static inline void set_irq_nested_thread(unsigned int irq, int nest)
 {
 	irq_set_nested_thread(irq, nest);
 }
 #endif

 int irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node);
 void irq_free_descs(unsigned int irq, unsigned int cnt);
 int irq_reserve_irqs(unsigned int from, unsigned int cnt);

 static inline int irq_alloc_desc(int node)
 {
 	return irq_alloc_descs(-1, 0, 1, node);
 }

 static inline int irq_alloc_desc_at(unsigned int at, int node)
 {
 	return irq_alloc_descs(at, at, 1, node);
 }

 static inline int irq_alloc_desc_from(unsigned int from, int node)
 {
 	return irq_alloc_descs(-1, from, 1, node);
 }

 static inline void irq_free_desc(unsigned int irq)
 {
 	irq_free_descs(irq, 1);
 }

 static inline int irq_reserve_irq(unsigned int irq)
 {
 	return irq_reserve_irqs(irq, 1);
 }

 #endif /* CONFIG_GENERIC_HARDIRQS */

 #endif /* !CONFIG_S390 */

 #endif /* _LINUX_IRQ_H */
	#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/gfp.h>
	#include <linux/irqreturn.h>
	#include <linux/irqnr.h>
	#include <linux/errno.h>
	#include <linux/topology.h>
	#include <linux/wait.h>

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

	struct irq_desc;
	typedef void (*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 */

	#ifndef CONFIG_GENERIC_HARDIRQS_NO_COMPAT
	#define IRQ_INPROGRESS 0x00000100 /* DEPRECATED */
	#define IRQ_REPLAY 0x00000200 /* DEPRECATED */
	#define IRQ_WAITING 0x00000400 /* DEPRECATED */
	#define IRQ_DISABLED 0x00000800 /* DEPRECATED */
	#define IRQ_PENDING 0x00001000 /* DEPRECATED */
	#define IRQ_MASKED 0x00002000 /* DEPRECATED */
	/* DEPRECATED use irq_setaffinity_pending() instead*/
	#define IRQ_MOVE_PENDING 0x00004000
	#endif

	#define IRQ_LEVEL 0x00008000 /* IRQ level triggered */
	#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_NO_BALANCING 0x00400000 /* IRQ is excluded from balancing */
	#define IRQ_MOVE_PCNTXT 0x01000000 /* IRQ migration from process context */
	#define IRQ_AFFINITY_SET 0x02000000 /* IRQ affinity was set from userspace*/
	#define IRQ_NESTED_THREAD 0x10000000 /* IRQ is nested into another, no own handler thread */

	#define IRQF_MODIFY_MASK \
	(IRQ_TYPE_SENSE_MASK \| IRQ_NOPROBE \| IRQ_NOREQUEST \| \
	IRQ_NOAUTOEN \| IRQ_MOVE_PCNTXT \| IRQ_LEVEL \| IRQ_NO_BALANCING \| \
	IRQ_PER_CPU \| IRQ_NESTED_THREAD)

	#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

	/*
	* Return value for chip->irq_set_affinity()
	*
	* IRQ_SET_MASK_OK - OK, core updates irq_data.affinity
	* IRQ_SET_MASK_NOCPY - OK, chip did update irq_data.affinity
	*/
	enum {
	IRQ_SET_MASK_OK = 0,
	IRQ_SET_MASK_OK_NOCOPY,
	};

	struct msi_desc;

	/**
	* struct irq_data - per irq and irq chip data passed down to chip functions
	* @irq: interrupt number
	* @node: node index useful for balancing
	* @state_use_accessor: status information for irq chip functions.
	* Use accessor functions to deal with it
	* @chip: low level interrupt hardware access
	* @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
	* @msi_desc: MSI descriptor
	* @affinity: IRQ affinity on SMP
	*
	* The fields here need to overlay the ones in irq_desc until we
	* cleaned up the direct references and switched everything over to
	* irq_data.
	*/
	struct irq_data {
	unsigned int irq;
	unsigned int node;
	unsigned int state_use_accessors;
	struct irq_chip *chip;
	void *handler_data;
	void *chip_data;
	struct msi_desc *msi_desc;
	#ifdef CONFIG_SMP
	cpumask_var_t affinity;
	#endif
	};

	/*
	* Bit masks for irq_data.state
	*
	* IRQD_SETAFFINITY_PENDING - Affinity setting is pending
	*/
	enum {
	/* Bit 0 - 7 reserved for TYPE will use later */
	IRQD_SETAFFINITY_PENDING = (1 << 8),
	};

	static inline bool irqd_is_setaffinity_pending(struct irq_data *d)
	{
	return d->state_use_accessors & IRQD_SETAFFINITY_PENDING;
	}

	/**
	* struct irq_chip - hardware interrupt chip descriptor
	*
	* @name: name for /proc/interrupts
	* @startup: deprecated, replaced by irq_startup
	* @shutdown: deprecated, replaced by irq_shutdown
	* @enable: deprecated, replaced by irq_enable
	* @disable: deprecated, replaced by irq_disable
	* @ack: deprecated, replaced by irq_ack
	* @mask: deprecated, replaced by irq_mask
	* @mask_ack: deprecated, replaced by irq_mask_ack
	* @unmask: deprecated, replaced by irq_unmask
	* @eoi: deprecated, replaced by irq_eoi
	* @end: deprecated, will go away with __do_IRQ()
	* @set_affinity: deprecated, replaced by irq_set_affinity
	* @retrigger: deprecated, replaced by irq_retrigger
	* @set_type: deprecated, replaced by irq_set_type
	* @set_wake: deprecated, replaced by irq_wake
	* @bus_lock: deprecated, replaced by irq_bus_lock
	* @bus_sync_unlock: deprecated, replaced by irq_bus_sync_unlock
	*
	* @irq_startup: start up the interrupt (defaults to ->enable if NULL)
	* @irq_shutdown: shut down the interrupt (defaults to ->disable if NULL)
	* @irq_enable: enable the interrupt (defaults to chip->unmask if NULL)
	* @irq_disable: disable the interrupt
	* @irq_ack: start of a new interrupt
	* @irq_mask: mask an interrupt source
	* @irq_mask_ack: ack and mask an interrupt source
	* @irq_unmask: unmask an interrupt source
	* @irq_eoi: end of interrupt
	* @irq_set_affinity: set the CPU affinity on SMP machines
	* @irq_retrigger: resend an IRQ to the CPU
	* @irq_set_type: set the flow type (IRQ_TYPE_LEVEL/etc.) of an IRQ
	* @irq_set_wake: enable/disable power-management wake-on of an IRQ
	* @irq_bus_lock: function to lock access to slow bus (i2c) chips
	* @irq_bus_sync_unlock:function to sync and unlock slow bus (i2c) chips
	*
	* @release: release function solely used by UML
	*/
	struct irq_chip {
	const char *name;
	#ifndef CONFIG_GENERIC_HARDIRQS_NO_DEPRECATED
	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);
	int (*set_affinity)(unsigned int irq,
	const struct cpumask *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);

	void (*bus_lock)(unsigned int irq);
	void (*bus_sync_unlock)(unsigned int irq);
	#endif
	unsigned int (irq_startup)(struct irq_data data);
	void (irq_shutdown)(struct irq_data data);
	void (irq_enable)(struct irq_data data);
	void (irq_disable)(struct irq_data data);

	void (irq_ack)(struct irq_data data);
	void (irq_mask)(struct irq_data data);
	void (irq_mask_ack)(struct irq_data data);
	void (irq_unmask)(struct irq_data data);
	void (irq_eoi)(struct irq_data data);

	int (irq_set_affinity)(struct irq_data data, const struct cpumask *dest, bool force);
	int (irq_retrigger)(struct irq_data data);
	int (irq_set_type)(struct irq_data data, unsigned int flow_type);
	int (irq_set_wake)(struct irq_data data, unsigned int on);

	void (irq_bus_lock)(struct irq_data data);
	void (irq_bus_sync_unlock)(struct irq_data data);

	/* Currently used only by UML, might disappear one day.*/
	#ifdef CONFIG_IRQ_RELEASE_METHOD
	void (release)(unsigned int irq, void dev_id);
	#endif
	};

	/* This include will go away once we isolated irq_desc usage to core code */
	#include <linux/irqdesc.h>

	/*
	* Pick up the arch-dependent methods:
	*/
	#include <asm/hw_irq.h>

	#ifndef NR_IRQS_LEGACY
	# define NR_IRQS_LEGACY 0
	#endif

	#ifndef ARCH_IRQ_INIT_FLAGS
	# define ARCH_IRQ_INIT_FLAGS 0
	#endif

	#define IRQ_DEFAULT_INIT_FLAGS ARCH_IRQ_INIT_FLAGS

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

	#ifdef CONFIG_GENERIC_HARDIRQS

	#if defined(CONFIG_SMP) && defined(CONFIG_GENERIC_PENDING_IRQ)
	void move_native_irq(int irq);
	void move_masked_irq(int irq);
	#else
	static inline void move_native_irq(int irq) { }
	static inline void move_masked_irq(int irq) { }
	#endif

	extern int no_irq_affinity;

	/* Handle irq action chains: */
	extern irqreturn_t handle_IRQ_event(unsigned int irq, struct irqaction *action);

	/*
	* Built-in IRQ handlers for various IRQ types,
	* callable via desc->handle_irq()
	*/
	extern void handle_level_irq(unsigned int irq, struct irq_desc *desc);
	extern void handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc);
	extern void handle_edge_irq(unsigned int irq, struct irq_desc *desc);
	extern void handle_simple_irq(unsigned int irq, struct irq_desc *desc);
	extern void handle_percpu_irq(unsigned int irq, struct irq_desc *desc);
	extern void handle_bad_irq(unsigned int irq, struct irq_desc *desc);
	extern void handle_nested_irq(unsigned int irq);

	/* Handling of unhandled and spurious interrupts: */
	extern void note_interrupt(unsigned int irq, struct irq_desc *desc,
	irqreturn_t action_ret);


	/* 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);
	}

	void irq_modify_status(unsigned int irq, unsigned long clr, unsigned long set);

	static inline void irq_set_status_flags(unsigned int irq, unsigned long set)
	{
	irq_modify_status(irq, 0, set);
	}

	static inline void irq_clear_status_flags(unsigned int irq, unsigned long clr)
	{
	irq_modify_status(irq, clr, 0);
	}

	static inline void irq_set_noprobe(unsigned int irq)
	{
	irq_modify_status(irq, 0, IRQ_NOPROBE);
	}

	static inline void irq_set_probe(unsigned int irq)
	{
	irq_modify_status(irq, IRQ_NOPROBE, 0);
	}

	static inline void irq_set_nested_thread(unsigned int irq, bool nest)
	{
	if (nest)
	irq_set_status_flags(irq, IRQ_NESTED_THREAD);
	else
	irq_clear_status_flags(irq, IRQ_NESTED_THREAD);
	}

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

	/*
	* Dynamic irq helper functions. Obsolete. Use irq_alloc_desc* and
	* irq_free_desc instead.
	*/
	extern void dynamic_irq_cleanup(unsigned int irq);
	static inline void dynamic_irq_init(unsigned int irq)
	{
	dynamic_irq_cleanup(irq);
	}

	/* Set/get chip/data for an IRQ: */
	extern int irq_set_chip(unsigned int irq, struct irq_chip *chip);
	extern int irq_set_handler_data(unsigned int irq, void *data);
	extern int irq_set_chip_data(unsigned int irq, void *data);
	extern int irq_set_irq_type(unsigned int irq, unsigned int type);
	extern int irq_set_msi_desc(unsigned int irq, struct msi_desc *entry);
	extern struct irq_data *irq_get_irq_data(unsigned int irq);

	static inline struct irq_chip *irq_get_chip(unsigned int irq)
	{
	struct irq_data *d = irq_get_irq_data(irq);
	return d ? d->chip : NULL;
	}

	static inline struct irq_chip irq_data_get_irq_chip(struct irq_data d)
	{
	return d->chip;
	}

	static inline void *irq_get_chip_data(unsigned int irq)
	{
	struct irq_data *d = irq_get_irq_data(irq);
	return d ? d->chip_data : NULL;
	}

	static inline void irq_data_get_irq_chip_data(struct irq_data d)
	{
	return d->chip_data;
	}

	static inline void *irq_get_handler_data(unsigned int irq)
	{
	struct irq_data *d = irq_get_irq_data(irq);
	return d ? d->handler_data : NULL;
	}

	static inline void irq_data_get_irq_handler_data(struct irq_data d)
	{
	return d->handler_data;
	}

	static inline struct msi_desc *irq_get_msi_desc(unsigned int irq)
	{
	struct irq_data *d = irq_get_irq_data(irq);
	return d ? d->msi_desc : NULL;
	}

	static inline struct msi_desc irq_data_get_msi(struct irq_data d)
	{
	return d->msi_desc;
	}

	#ifndef CONFIG_GENERIC_HARDIRQS_NO_COMPAT
	/* Please do not use: Use the replacement functions instead */
	static inline int set_irq_chip(unsigned int irq, struct irq_chip *chip)
	{
	return irq_set_chip(irq, chip);
	}
	static inline int set_irq_data(unsigned int irq, void *data)
	{
	return irq_set_handler_data(irq, data);
	}
	static inline int set_irq_chip_data(unsigned int irq, void *data)
	{
	return irq_set_chip_data(irq, data);
	}
	static inline int set_irq_type(unsigned int irq, unsigned int type)
	{
	return irq_set_irq_type(irq, type);
	}
	static inline int set_irq_msi(unsigned int irq, struct msi_desc *entry)
	{
	return irq_set_msi_desc(irq, entry);
	}
	static inline struct irq_chip *get_irq_chip(unsigned int irq)
	{
	return irq_get_chip(irq);
	}
	static inline void *get_irq_chip_data(unsigned int irq)
	{
	return irq_get_chip_data(irq);
	}
	static inline void *get_irq_data(unsigned int irq)
	{
	return irq_get_handler_data(irq);
	}
	static inline void irq_data_get_irq_data(struct irq_data d)
	{
	return irq_data_get_irq_handler_data(d);
	}
	static inline struct msi_desc *get_irq_msi(unsigned int irq)
	{
	return irq_get_msi_desc(irq);
	}
	static inline void set_irq_noprobe(unsigned int irq)
	{
	irq_set_noprobe(irq);
	}
	static inline void set_irq_probe(unsigned int irq)
	{
	irq_set_probe(irq);
	}
	static inline void set_irq_nested_thread(unsigned int irq, int nest)
	{
	irq_set_nested_thread(irq, nest);
	}
	#endif

	int irq_alloc_descs(int irq, unsigned int from, unsigned int cnt, int node);
	void irq_free_descs(unsigned int irq, unsigned int cnt);
	int irq_reserve_irqs(unsigned int from, unsigned int cnt);

	static inline int irq_alloc_desc(int node)
	{
	return irq_alloc_descs(-1, 0, 1, node);
	}

	static inline int irq_alloc_desc_at(unsigned int at, int node)
	{
	return irq_alloc_descs(at, at, 1, node);
	}

	static inline int irq_alloc_desc_from(unsigned int from, int node)
	{
	return irq_alloc_descs(-1, from, 1, node);
	}

	static inline void irq_free_desc(unsigned int irq)
	{
	irq_free_descs(irq, 1);
	}

	static inline int irq_reserve_irq(unsigned int irq)
	{
	return irq_reserve_irqs(irq, 1);
	}

	#endif /* CONFIG_GENERIC_HARDIRQS */

	#endif /* !CONFIG_S390 */

	#endif /* _LINUX_IRQ_H */