/* -*- linux-c -*-
   *
   *	$Id: sysrq.h,v 1.3 1997/07/17 11:54:33 mj Exp $
   *
   *	Linux Magic System Request Key Hacks
   *
   *	(c) 1997 Martin Mares <mj@atrey.karlin.mff.cuni.cz>
   *
   *	(c) 2000 Crutcher Dunnavant <crutcher+kernel@datastacks.com>
   *	overhauled to use key registration
   *	based upon discusions in irc://irc.openprojects.net/#kernelnewbies
   */

  #ifndef _LINUX_SYSRQ_H
  #define _LINUX_SYSRQ_H

  #include <linux/errno.h>

  #include <linux/types.h>

  /* Enable/disable SYSRQ support by default (0==no, 1==yes). */
  #define SYSRQ_DEFAULT_ENABLE	1

  /* Possible values of bitmask for enabling sysrq functions */
  /* 0x0001 is reserved for enable everything */
  #define SYSRQ_ENABLE_LOG	0x0002
  #define SYSRQ_ENABLE_KEYBOARD	0x0004
  #define SYSRQ_ENABLE_DUMP	0x0008
  #define SYSRQ_ENABLE_SYNC	0x0010
  #define SYSRQ_ENABLE_REMOUNT	0x0020
  #define SYSRQ_ENABLE_SIGNAL	0x0040
  #define SYSRQ_ENABLE_BOOT	0x0080
  #define SYSRQ_ENABLE_RTNICE	0x0100
  
  struct sysrq_key_op {

  	void (*handler)(int);

  	char *help_msg;
  	char *action_msg;
  	int enable_mask;
  };
  
  #ifdef CONFIG_MAGIC_SYSRQ
  
  /* Generic SysRq interface -- you may call it from any device driver, supplying
   * ASCII code of the key, pointer to registers and kbd/tty structs (if they
   * are available -- else NULL's).
   */

  void handle_sysrq(int key);
  void __handle_sysrq(int key, bool check_mask);

  int register_sysrq_key(int key, struct sysrq_key_op *op);
  int unregister_sysrq_key(int key, struct sysrq_key_op *op);

  struct sysrq_key_op *__sysrq_get_key_op(int key);

  int sysrq_toggle_support(int enable_mask);

  #else

  static inline void handle_sysrq(int key)

  {

  }

  static inline void __handle_sysrq(int key, bool check_mask)

  {
  }

  static inline int register_sysrq_key(int key, struct sysrq_key_op *op)

  {
  	return -EINVAL;
  }

  
  static inline int unregister_sysrq_key(int key, struct sysrq_key_op *op)

  {

  	return -EINVAL;

  }

  #endif

  
  #endif /* _LINUX_SYSRQ_H */