drivers/scsi/isci/state_machine.h

   1 /*
   2  * This file is provided under a dual BSD/GPLv2 license.  When using or
   3  * redistributing this file, you may do so under either license.
   4  *
   5  * GPL LICENSE SUMMARY
   6  *
   7  * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of version 2 of the GNU General Public License as
  11  * published by the Free Software Foundation.
  12  *
  13  * This program is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  21  * The full GNU General Public License is included in this distribution
  22  * in the file called LICENSE.GPL.
  23  *
  24  * BSD LICENSE
  25  *
  26  * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
  27  * All rights reserved.
  28  *
  29  * Redistribution and use in source and binary forms, with or without
  30  * modification, are permitted provided that the following conditions
  31  * are met:
  32  *
  33  *   * Redistributions of source code must retain the above copyright
  34  *     notice, this list of conditions and the following disclaimer.
  35  *   * Redistributions in binary form must reproduce the above copyright
  36  *     notice, this list of conditions and the following disclaimer in
  37  *     the documentation and/or other materials provided with the
  38  *     distribution.
  39  *   * Neither the name of Intel Corporation nor the names of its
  40  *     contributors may be used to endorse or promote products derived
  41  *     from this software without specific prior written permission.
  42  *
  43  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  44  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  45  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  46  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  47  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  48  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  49  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  50  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  51  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  52  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  53  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  54  */
  55
  56 #ifndef _SCI_BASE_STATE_MACHINE_H_
  57 #define _SCI_BASE_STATE_MACHINE_H_
  58
  59 #include <linux/types.h>
  60
  61 struct sci_base_state_machine;
  62 typedef void (*sci_base_state_handler_t)(void);
  63 typedef void (*sci_state_transition_t)(struct sci_base_state_machine *sm);
  64
  65 /**
  66  * struct sci_base_state - The base state object abstracts the fields common to
  67  *    all state objects defined in SCI.
  68  *
  69  *
  70  */
  71 struct sci_base_state {
  72         /**
  73          * This field is a function pointer that defines the method to be
  74          * invoked when the state is entered.
  75          */
  76         sci_state_transition_t enter_state;
  77
  78         /**
  79          * This field is a function pointer that defines the method to be
  80          * invoked when the state is exited.
  81          */
  82         sci_state_transition_t exit_state;
  83 };
  84
  85 /**
  86  * struct sci_base_state_machine - This structure defines the fields common to
  87  *    all state machines.
  88  *
  89  *
  90  */
  91 struct sci_base_state_machine {
  92         /**
  93          * This field points to the start of the state machine's state table.
  94          */
  95         const struct sci_base_state *state_table;
  96
  97         /**
  98          * This field simply indicates the state value for the state machine's
  99          * initial state.
 100          */
 101         u32 initial_state_id;
 102
 103         /**
 104          * This field indicates the current state of the state machine.
 105          */
 106         u32 current_state_id;
 107
 108         /**
 109          * This field indicates the previous state of the state machine.
 110          */
 111         u32 previous_state_id;
 112
 113 };
 114
 115 void sci_base_state_machine_construct(struct sci_base_state_machine *sm,
 116                                       const struct sci_base_state *state_table,
 117                                       u32 initial_state);
 118 void sci_base_state_machine_start(struct sci_base_state_machine *sm);
 119 void sci_base_state_machine_stop(struct sci_base_state_machine *sm);
 120 void sci_base_state_machine_change_state(struct sci_base_state_machine *sm,
 121                                          u32 next_state);
 122 u32 sci_base_state_machine_get_state(struct sci_base_state_machine *sm);
 123
 124 #endif /* _SCI_BASE_STATE_MACHINE_H_ */