LXR linux/drivers/char/ipmi/ipmi_si

   1/* SPDX-License-Identifier: GPL-2.0+ */
   2/*
   3 * ipmi_si_sm.h
   4 *
   5 * State machine interface for low-level IPMI system management
   6 * interface state machines.  This code is the interface between
   7 * the ipmi_smi code (that handles the policy of a KCS, SMIC, or
   8 * BT interface) and the actual low-level state machine.
   9 *
  10 * Author: MontaVista Software, Inc.
  11 *         Corey Minyard <minyard@mvista.com>
  12 *         source@mvista.com
  13 *
  14 * Copyright 2002 MontaVista Software Inc.
  15 */
  16
  17#ifndef __IPMI_SI_SM_H__
  18#define __IPMI_SI_SM_H__
  19
  20#include "ipmi_si.h"
  21
  22/*
  23 * This is defined by the state machines themselves, it is an opaque
  24 * data type for them to use.
  25 */
  26struct si_sm_data;
  27
  28/* Results of SMI events. */
  29enum si_sm_result {
  30        SI_SM_CALL_WITHOUT_DELAY, /* Call the driver again immediately */
  31        SI_SM_CALL_WITH_DELAY,  /* Delay some before calling again. */
  32        SI_SM_CALL_WITH_TICK_DELAY,/* Delay >=1 tick before calling again. */
  33        SI_SM_TRANSACTION_COMPLETE, /* A transaction is finished. */
  34        SI_SM_IDLE,             /* The SM is in idle state. */
  35        SI_SM_HOSED,            /* The hardware violated the state machine. */
  36
  37        /*
  38         * The hardware is asserting attn and the state machine is
  39         * idle.
  40         */
  41        SI_SM_ATTN
  42};
  43
  44/* Handlers for the SMI state machine. */
  45struct si_sm_handlers {
  46        /*
  47         * Put the version number of the state machine here so the
  48         * upper layer can print it.
  49         */
  50        char *version;
  51
  52        /*
  53         * Initialize the data and return the amount of I/O space to
  54         * reserve for the space.
  55         */
  56        unsigned int (*init_data)(struct si_sm_data *smi,
  57                                  struct si_sm_io   *io);
  58
  59        /*
  60         * Start a new transaction in the state machine.  This will
  61         * return -2 if the state machine is not idle, -1 if the size
  62         * is invalid (to large or too small), or 0 if the transaction
  63         * is successfully completed.
  64         */
  65        int (*start_transaction)(struct si_sm_data *smi,
  66                                 unsigned char *data, unsigned int size);
  67
  68        /*
  69         * Return the results after the transaction.  This will return
  70         * -1 if the buffer is too small, zero if no transaction is
  71         * present, or the actual length of the result data.
  72         */
  73        int (*get_result)(struct si_sm_data *smi,
  74                          unsigned char *data, unsigned int length);
  75
  76        /*
  77         * Call this periodically (for a polled interface) or upon
  78         * receiving an interrupt (for a interrupt-driven interface).
  79         * If interrupt driven, you should probably poll this
  80         * periodically when not in idle state.  This should be called
  81         * with the time that passed since the last call, if it is
  82         * significant.  Time is in microseconds.
  83         */
  84        enum si_sm_result (*event)(struct si_sm_data *smi, long time);
  85
  86        /*
  87         * Attempt to detect an SMI.  Returns 0 on success or nonzero
  88         * on failure.
  89         */
  90        int (*detect)(struct si_sm_data *smi);
  91
  92        /* The interface is shutting down, so clean it up. */
  93        void (*cleanup)(struct si_sm_data *smi);
  94
  95        /* Return the size of the SMI structure in bytes. */
  96        int (*size)(void);
  97};
  98
  99/* Current state machines that we can use. */
 100extern const struct si_sm_handlers kcs_smi_handlers;
 101extern const struct si_sm_handlers smic_smi_handlers;
 102extern const struct si_sm_handlers bt_smi_handlers;
 103
 104#endif /* __IPMI_SI_SM_H__ */
 105