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Diffstat (limited to 'drivers/scsi/isci/core/sci_base_state_machine.c')
| -rw-r--r-- | drivers/scsi/isci/core/sci_base_state_machine.c | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/drivers/scsi/isci/core/sci_base_state_machine.c b/drivers/scsi/isci/core/sci_base_state_machine.c new file mode 100644 index 000000000000..5b1e8da55fe6 --- /dev/null +++ b/drivers/scsi/isci/core/sci_base_state_machine.c @@ -0,0 +1,182 @@ +/* + * This file is provided under a dual BSD/GPLv2 license. When using or + * redistributing this file, you may do so under either license. + * + * GPL LICENSE SUMMARY + * + * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. + * The full GNU General Public License is included in this distribution + * in the file called LICENSE.GPL. + * + * BSD LICENSE + * + * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * * Neither the name of Intel Corporation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +/** + * This file contains all of the functionality common to all state machine + * object implementations. + * + * + */ + +#include "sci_base_state_machine.h" + +static void sci_state_machine_exit_state(struct sci_base_state_machine *sm) +{ + u32 state = sm->current_state_id; + SCI_STATE_TRANSITION_T exit = sm->state_table[state].exit_state; + + if (exit) + exit(sm->state_machine_owner); +} + +static void sci_state_machine_enter_state(struct sci_base_state_machine *sm) +{ + u32 state = sm->current_state_id; + SCI_STATE_TRANSITION_T enter = sm->state_table[state].enter_state; + + if (enter) + enter(sm->state_machine_owner); +} + +/* + * ****************************************************************************** + * * P R O T E C T E D M E T H O D S + * ****************************************************************************** */ + +/** + * This method will set the initial state and state table for the state + * machine. The caller should follow this request with the initialize + * request to cause the state machine to start. + * @sm: This parameter provides the state machine object to be + * constructed. + * @state_machine_owner: This parameter indicates the object that is owns the + * state machine being constructed. + * @state_table: This parameter specifies the table of state objects that is + * managed by this state machine. + * @initial_state: This parameter specifies the value of the initial state for + * this state machine. + * + */ +void sci_base_state_machine_construct(struct sci_base_state_machine *sm, + struct sci_base_object *owner, + const struct sci_base_state *state_table, + u32 initial_state) +{ + sm->state_machine_owner = owner; + sm->initial_state_id = initial_state; + sm->previous_state_id = initial_state; + sm->current_state_id = initial_state; + sm->state_table = state_table; +} + +/** + * This method will cause the state machine to enter the initial state. + * @sm: This parameter specifies the state machine that is to + * be started. + * + * sci_base_state_machine_construct() for how to set the initial state none + */ +void sci_base_state_machine_start(struct sci_base_state_machine *sm) +{ + sm->current_state_id = sm->initial_state_id; +#if defined(SCI_BASE_ENABLE_SUBJECT_NOTIFICATION) + sci_base_subject_notify(&sm->parent); +#endif + sci_state_machine_enter_state(sm); +} + +/** + * This method will cause the state machine to exit it's current state only. + * @sm: This parameter specifies the state machine that is to + * be stopped. + * + */ +void sci_base_state_machine_stop( + struct sci_base_state_machine *sm) +{ + sci_state_machine_exit_state(sm); +#if defined(SCI_BASE_ENABLE_SUBJECT_NOTIFICATION) + sci_base_subject_notify(&sm->parent); +#endif +} + +/** + * This method performs an update to the current state of the state machine. + * @sm: This parameter specifies the state machine for which + * the caller wishes to perform a state change. + * @next_state: This parameter specifies the new state for the state machine. + * + */ +void sci_base_state_machine_change_state( + struct sci_base_state_machine *sm, + u32 next_state) +{ + sci_state_machine_exit_state(sm); + + sm->previous_state_id = sm->current_state_id; + sm->current_state_id = next_state; + +#if defined(SCI_BASE_ENABLE_SUBJECT_NOTIFICATION) + /* Notify of the state change prior to entering the state. */ + sci_base_subject_notify(&sm->parent); +#endif + + sci_state_machine_enter_state(sm); +} + +/** + * This method simply returns the current state of the state machine to the + * caller. + * @sm: This parameter specifies the state machine for which to + * retrieve the current state. + * + * This method returns a u32 value indicating the current state for the + * supplied state machine. + */ +u32 sci_base_state_machine_get_state(struct sci_base_state_machine *sm) +{ + return sm->current_state_id; +} + |