usb: otg: mv_otg: Add dependence

[zen-stable.git] / drivers / scsi / isci / remote_node_context.c

/*
 * 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.
 */

#include "host.h"
#include "isci.h"
#include "remote_device.h"
#include "remote_node_context.h"
#include "scu_event_codes.h"
#include "scu_task_context.h"


/**
 *
 * @sci_rnc: The RNC for which the is posted request is being made.
 *
 * This method will return true if the RNC is not in the initial state.  In all
 * other states the RNC is considered active and this will return true. The
 * destroy request of the state machine drives the RNC back to the initial
 * state.  If the state machine changes then this routine will also have to be
 * changed. bool true if the state machine is not in the initial state false if
 * the state machine is in the initial state
 */

/**
 *
 * @sci_rnc: The state of the remote node context object to check.
 *
 * This method will return true if the remote node context is in a READY state
 * otherwise it will return false bool true if the remote node context is in
 * the ready state. false if the remote node context is not in the ready state.
 */
bool sci_remote_node_context_is_ready(
        struct sci_remote_node_context *sci_rnc)
{
        u32 current_state = sci_rnc->sm.current_state_id;

        if (current_state == SCI_RNC_READY) {
                return true;
        }

        return false;
}

static union scu_remote_node_context *sci_rnc_by_id(struct isci_host *ihost, u16 id)
{
        if (id < ihost->remote_node_entries &&
            ihost->device_table[id])
                return &ihost->remote_node_context_table[id];

        return NULL;
}

static void sci_remote_node_context_construct_buffer(struct sci_remote_node_context *sci_rnc)
{
        struct isci_remote_device *idev = rnc_to_dev(sci_rnc);
        struct domain_device *dev = idev->domain_dev;
        int rni = sci_rnc->remote_node_index;
        union scu_remote_node_context *rnc;
        struct isci_host *ihost;
        __le64 sas_addr;

        ihost = idev->owning_port->owning_controller;
        rnc = sci_rnc_by_id(ihost, rni);

        memset(rnc, 0, sizeof(union scu_remote_node_context)
                * sci_remote_device_node_count(idev));

        rnc->ssp.remote_node_index = rni;
        rnc->ssp.remote_node_port_width = idev->device_port_width;
        rnc->ssp.logical_port_index = idev->owning_port->physical_port_index;

        /* sas address is __be64, context ram format is __le64 */
        sas_addr = cpu_to_le64(SAS_ADDR(dev->sas_addr));
        rnc->ssp.remote_sas_address_hi = upper_32_bits(sas_addr);
        rnc->ssp.remote_sas_address_lo = lower_32_bits(sas_addr);

        rnc->ssp.nexus_loss_timer_enable = true;
        rnc->ssp.check_bit               = false;
        rnc->ssp.is_valid                = false;
        rnc->ssp.is_remote_node_context  = true;
        rnc->ssp.function_number         = 0;

        rnc->ssp.arbitration_wait_time = 0;

        if (dev->dev_type == SATA_DEV || (dev->tproto & SAS_PROTOCOL_STP)) {
                rnc->ssp.connection_occupancy_timeout =
                        ihost->user_parameters.stp_max_occupancy_timeout;
                rnc->ssp.connection_inactivity_timeout =
                        ihost->user_parameters.stp_inactivity_timeout;
        } else {
                rnc->ssp.connection_occupancy_timeout  =
                        ihost->user_parameters.ssp_max_occupancy_timeout;
                rnc->ssp.connection_inactivity_timeout =
                        ihost->user_parameters.ssp_inactivity_timeout;
        }

        rnc->ssp.initial_arbitration_wait_time = 0;

        /* Open Address Frame Parameters */
        rnc->ssp.oaf_connection_rate = idev->connection_rate;
        rnc->ssp.oaf_features = 0;
        rnc->ssp.oaf_source_zone_group = 0;
        rnc->ssp.oaf_more_compatibility_features = 0;
}

/**
 *
 * @sci_rnc:
 * @callback:
 * @callback_parameter:
 *
 * This method will setup the remote node context object so it will transition
 * to its ready state.  If the remote node context is already setup to
 * transition to its final state then this function does nothing. none
 */
static void sci_remote_node_context_setup_to_resume(
        struct sci_remote_node_context *sci_rnc,
        scics_sds_remote_node_context_callback callback,
        void *callback_parameter)
{
        if (sci_rnc->destination_state != SCIC_SDS_REMOTE_NODE_DESTINATION_STATE_FINAL) {
                sci_rnc->destination_state = SCIC_SDS_REMOTE_NODE_DESTINATION_STATE_READY;
                sci_rnc->user_callback     = callback;
                sci_rnc->user_cookie       = callback_parameter;
        }
}

static void sci_remote_node_context_setup_to_destory(
        struct sci_remote_node_context *sci_rnc,
        scics_sds_remote_node_context_callback callback,
        void *callback_parameter)
{
        sci_rnc->destination_state = SCIC_SDS_REMOTE_NODE_DESTINATION_STATE_FINAL;
        sci_rnc->user_callback     = callback;
        sci_rnc->user_cookie       = callback_parameter;
}

/**
 *
 *
 * This method just calls the user callback function and then resets the
 * callback.
 */
static void sci_remote_node_context_notify_user(
        struct sci_remote_node_context *rnc)
{
        if (rnc->user_callback != NULL) {
                (*rnc->user_callback)(rnc->user_cookie);

                rnc->user_callback = NULL;
                rnc->user_cookie = NULL;
        }
}

static void sci_remote_node_context_continue_state_transitions(struct sci_remote_node_context *rnc)
{
        if (rnc->destination_state == SCIC_SDS_REMOTE_NODE_DESTINATION_STATE_READY)
                sci_remote_node_context_resume(rnc, rnc->user_callback,
                                                    rnc->user_cookie);
}

static void sci_remote_node_context_validate_context_buffer(struct sci_remote_node_context *sci_rnc)
{
        union scu_remote_node_context *rnc_buffer;
        struct isci_remote_device *idev = rnc_to_dev(sci_rnc);
        struct domain_device *dev = idev->domain_dev;
        struct isci_host *ihost = idev->owning_port->owning_controller;

        rnc_buffer = sci_rnc_by_id(ihost, sci_rnc->remote_node_index);

        rnc_buffer->ssp.is_valid = true;

        if (!idev->is_direct_attached &&
            (dev->dev_type == SATA_DEV || (dev->tproto & SAS_PROTOCOL_STP))) {
                sci_remote_device_post_request(idev, SCU_CONTEXT_COMMAND_POST_RNC_96);
        } else {
                sci_remote_device_post_request(idev, SCU_CONTEXT_COMMAND_POST_RNC_32);

                if (idev->is_direct_attached)
                        sci_port_setup_transports(idev->owning_port,
                                                  sci_rnc->remote_node_index);
        }
}

static void sci_remote_node_context_invalidate_context_buffer(struct sci_remote_node_context *sci_rnc)
{
        union scu_remote_node_context *rnc_buffer;
        struct isci_remote_device *idev = rnc_to_dev(sci_rnc);
        struct isci_host *ihost = idev->owning_port->owning_controller;

        rnc_buffer = sci_rnc_by_id(ihost, sci_rnc->remote_node_index);

        rnc_buffer->ssp.is_valid = false;

        sci_remote_device_post_request(rnc_to_dev(sci_rnc),
                                       SCU_CONTEXT_COMMAND_POST_RNC_INVALIDATE);
}

static void sci_remote_node_context_initial_state_enter(struct sci_base_state_machine *sm)
{
        struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);

        /* Check to see if we have gotten back to the initial state because
         * someone requested to destroy the remote node context object.
         */
        if (sm->previous_state_id == SCI_RNC_INVALIDATING) {
                rnc->destination_state = SCIC_SDS_REMOTE_NODE_DESTINATION_STATE_UNSPECIFIED;
                sci_remote_node_context_notify_user(rnc);
        }
}

static void sci_remote_node_context_posting_state_enter(struct sci_base_state_machine *sm)
{
        struct sci_remote_node_context *sci_rnc = container_of(sm, typeof(*sci_rnc), sm);

        sci_remote_node_context_validate_context_buffer(sci_rnc);
}

static void sci_remote_node_context_invalidating_state_enter(struct sci_base_state_machine *sm)
{
        struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);

        sci_remote_node_context_invalidate_context_buffer(rnc);
}

static void sci_remote_node_context_resuming_state_enter(struct sci_base_state_machine *sm)
{
        struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);
        struct isci_remote_device *idev;
        struct domain_device *dev;

        idev = rnc_to_dev(rnc);
        dev = idev->domain_dev;

        /*
         * For direct attached SATA devices we need to clear the TLCR
         * NCQ to TCi tag mapping on the phy and in cases where we
         * resume because of a target reset we also need to update
         * the STPTLDARNI register with the RNi of the device
         */
        if ((dev->dev_type == SATA_DEV || (dev->tproto & SAS_PROTOCOL_STP)) &&
            idev->is_direct_attached)
                sci_port_setup_transports(idev->owning_port,
                                               rnc->remote_node_index);

        sci_remote_device_post_request(idev, SCU_CONTEXT_COMMAND_POST_RNC_RESUME);
}

static void sci_remote_node_context_ready_state_enter(struct sci_base_state_machine *sm)
{
        struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);

        rnc->destination_state = SCIC_SDS_REMOTE_NODE_DESTINATION_STATE_UNSPECIFIED;

        if (rnc->user_callback)
                sci_remote_node_context_notify_user(rnc);
}

static void sci_remote_node_context_tx_suspended_state_enter(struct sci_base_state_machine *sm)
{
        struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);

        sci_remote_node_context_continue_state_transitions(rnc);
}

static void sci_remote_node_context_tx_rx_suspended_state_enter(struct sci_base_state_machine *sm)
{
        struct sci_remote_node_context *rnc = container_of(sm, typeof(*rnc), sm);

        sci_remote_node_context_continue_state_transitions(rnc);
}

static const struct sci_base_state sci_remote_node_context_state_table[] = {
        [SCI_RNC_INITIAL] = {
                .enter_state = sci_remote_node_context_initial_state_enter,
        },
        [SCI_RNC_POSTING] = {
                .enter_state = sci_remote_node_context_posting_state_enter,
        },
        [SCI_RNC_INVALIDATING] = {
                .enter_state = sci_remote_node_context_invalidating_state_enter,
        },
        [SCI_RNC_RESUMING] = {
                .enter_state = sci_remote_node_context_resuming_state_enter,
        },
        [SCI_RNC_READY] = {
                .enter_state = sci_remote_node_context_ready_state_enter,
        },
        [SCI_RNC_TX_SUSPENDED] = {
                .enter_state = sci_remote_node_context_tx_suspended_state_enter,
        },
        [SCI_RNC_TX_RX_SUSPENDED] = {
                .enter_state = sci_remote_node_context_tx_rx_suspended_state_enter,
        },
        [SCI_RNC_AWAIT_SUSPENSION] = { },
};

void sci_remote_node_context_construct(struct sci_remote_node_context *rnc,
                                            u16 remote_node_index)
{
        memset(rnc, 0, sizeof(struct sci_remote_node_context));

        rnc->remote_node_index = remote_node_index;
        rnc->destination_state = SCIC_SDS_REMOTE_NODE_DESTINATION_STATE_UNSPECIFIED;

        sci_init_sm(&rnc->sm, sci_remote_node_context_state_table, SCI_RNC_INITIAL);
}

enum sci_status sci_remote_node_context_event_handler(struct sci_remote_node_context *sci_rnc,
                                                           u32 event_code)
{
        enum scis_sds_remote_node_context_states state;

        state = sci_rnc->sm.current_state_id;
        switch (state) {
        case SCI_RNC_POSTING:
                switch (scu_get_event_code(event_code)) {
                case SCU_EVENT_POST_RNC_COMPLETE:
                        sci_change_state(&sci_rnc->sm, SCI_RNC_READY);
                        break;
                default:
                        goto out;
                }
                break;
        case SCI_RNC_INVALIDATING:
                if (scu_get_event_code(event_code) == SCU_EVENT_POST_RNC_INVALIDATE_COMPLETE) {
                        if (sci_rnc->destination_state == SCIC_SDS_REMOTE_NODE_DESTINATION_STATE_FINAL)
                                state = SCI_RNC_INITIAL;
                        else
                                state = SCI_RNC_POSTING;
                        sci_change_state(&sci_rnc->sm, state);
                } else {
                        switch (scu_get_event_type(event_code)) {
                        case SCU_EVENT_TYPE_RNC_SUSPEND_TX:
                        case SCU_EVENT_TYPE_RNC_SUSPEND_TX_RX:
                                /* We really dont care if the hardware is going to suspend
                                 * the device since it's being invalidated anyway */
                                dev_dbg(scirdev_to_dev(rnc_to_dev(sci_rnc)),
                                        "%s: SCIC Remote Node Context 0x%p was "
                                        "suspeneded by hardware while being "
                                        "invalidated.\n", __func__, sci_rnc);
                                break;
                        default:
                                goto out;
                        }
                }
                break;
        case SCI_RNC_RESUMING:
                if (scu_get_event_code(event_code) == SCU_EVENT_POST_RCN_RELEASE) {
                        sci_change_state(&sci_rnc->sm, SCI_RNC_READY);
                } else {
                        switch (scu_get_event_type(event_code)) {
                        case SCU_EVENT_TYPE_RNC_SUSPEND_TX:
                        case SCU_EVENT_TYPE_RNC_SUSPEND_TX_RX:
                                /* We really dont care if the hardware is going to suspend
                                 * the device since it's being resumed anyway */
                                dev_dbg(scirdev_to_dev(rnc_to_dev(sci_rnc)),
                                        "%s: SCIC Remote Node Context 0x%p was "
                                        "suspeneded by hardware while being resumed.\n",
                                        __func__, sci_rnc);
                                break;
                        default:
                                goto out;
                        }
                }
                break;
        case SCI_RNC_READY:
                switch (scu_get_event_type(event_code)) {
                case SCU_EVENT_TL_RNC_SUSPEND_TX:
                        sci_change_state(&sci_rnc->sm, SCI_RNC_TX_SUSPENDED);
                        sci_rnc->suspension_code = scu_get_event_specifier(event_code);
                        break;
                case SCU_EVENT_TL_RNC_SUSPEND_TX_RX:
                        sci_change_state(&sci_rnc->sm, SCI_RNC_TX_RX_SUSPENDED);
                        sci_rnc->suspension_code = scu_get_event_specifier(event_code);
                        break;
                default:
                        goto out;
                }
                break;
        case SCI_RNC_AWAIT_SUSPENSION:
                switch (scu_get_event_type(event_code)) {
                case SCU_EVENT_TL_RNC_SUSPEND_TX:
                        sci_change_state(&sci_rnc->sm, SCI_RNC_TX_SUSPENDED);
                        sci_rnc->suspension_code = scu_get_event_specifier(event_code);
                        break;
                case SCU_EVENT_TL_RNC_SUSPEND_TX_RX:
                        sci_change_state(&sci_rnc->sm, SCI_RNC_TX_RX_SUSPENDED);
                        sci_rnc->suspension_code = scu_get_event_specifier(event_code);
                        break;
                default:
                        goto out;
                }
                break;
        default:
                dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
                         "%s: invalid state %d\n", __func__, state);
                return SCI_FAILURE_INVALID_STATE;
        }
        return SCI_SUCCESS;

 out:
        dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
                 "%s: code: %#x state: %d\n", __func__, event_code, state);
        return SCI_FAILURE;

}

enum sci_status sci_remote_node_context_destruct(struct sci_remote_node_context *sci_rnc,
                                                      scics_sds_remote_node_context_callback cb_fn,
                                                      void *cb_p)
{
        enum scis_sds_remote_node_context_states state;

        state = sci_rnc->sm.current_state_id;
        switch (state) {
        case SCI_RNC_INVALIDATING:
                sci_remote_node_context_setup_to_destory(sci_rnc, cb_fn, cb_p);
                return SCI_SUCCESS;
        case SCI_RNC_POSTING:
        case SCI_RNC_RESUMING:
        case SCI_RNC_READY:
        case SCI_RNC_TX_SUSPENDED:
        case SCI_RNC_TX_RX_SUSPENDED:
        case SCI_RNC_AWAIT_SUSPENSION:
                sci_remote_node_context_setup_to_destory(sci_rnc, cb_fn, cb_p);
                sci_change_state(&sci_rnc->sm, SCI_RNC_INVALIDATING);
                return SCI_SUCCESS;
        case SCI_RNC_INITIAL:
                dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
                         "%s: invalid state %d\n", __func__, state);
                /* We have decided that the destruct request on the remote node context
                 * can not fail since it is either in the initial/destroyed state or is
                 * can be destroyed.
                 */
                return SCI_SUCCESS;
        default:
                dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
                         "%s: invalid state %d\n", __func__, state);
                return SCI_FAILURE_INVALID_STATE;
        }
}

enum sci_status sci_remote_node_context_suspend(struct sci_remote_node_context *sci_rnc,
                                                     u32 suspend_type,
                                                     scics_sds_remote_node_context_callback cb_fn,
                                                     void *cb_p)
{
        enum scis_sds_remote_node_context_states state;

        state = sci_rnc->sm.current_state_id;
        if (state != SCI_RNC_READY) {
                dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
                         "%s: invalid state %d\n", __func__, state);
                return SCI_FAILURE_INVALID_STATE;
        }

        sci_rnc->user_callback   = cb_fn;
        sci_rnc->user_cookie     = cb_p;
        sci_rnc->suspension_code = suspend_type;

        if (suspend_type == SCI_SOFTWARE_SUSPENSION) {
                sci_remote_device_post_request(rnc_to_dev(sci_rnc),
                                                    SCU_CONTEXT_COMMAND_POST_RNC_SUSPEND_TX);
        }

        sci_change_state(&sci_rnc->sm, SCI_RNC_AWAIT_SUSPENSION);
        return SCI_SUCCESS;
}

enum sci_status sci_remote_node_context_resume(struct sci_remote_node_context *sci_rnc,
                                                    scics_sds_remote_node_context_callback cb_fn,
                                                    void *cb_p)
{
        enum scis_sds_remote_node_context_states state;

        state = sci_rnc->sm.current_state_id;
        switch (state) {
        case SCI_RNC_INITIAL:
                if (sci_rnc->remote_node_index == SCIC_SDS_REMOTE_NODE_CONTEXT_INVALID_INDEX)
                        return SCI_FAILURE_INVALID_STATE;

                sci_remote_node_context_setup_to_resume(sci_rnc, cb_fn, cb_p);
                sci_remote_node_context_construct_buffer(sci_rnc);
                sci_change_state(&sci_rnc->sm, SCI_RNC_POSTING);
                return SCI_SUCCESS;
        case SCI_RNC_POSTING:
        case SCI_RNC_INVALIDATING:
        case SCI_RNC_RESUMING:
                if (sci_rnc->destination_state != SCIC_SDS_REMOTE_NODE_DESTINATION_STATE_READY)
                        return SCI_FAILURE_INVALID_STATE;

                sci_rnc->user_callback = cb_fn;
                sci_rnc->user_cookie   = cb_p;
                return SCI_SUCCESS;
        case SCI_RNC_TX_SUSPENDED: {
                struct isci_remote_device *idev = rnc_to_dev(sci_rnc);
                struct domain_device *dev = idev->domain_dev;

                sci_remote_node_context_setup_to_resume(sci_rnc, cb_fn, cb_p);

                /* TODO: consider adding a resume action of NONE, INVALIDATE, WRITE_TLCR */
                if (dev->dev_type == SAS_END_DEV || dev_is_expander(dev))
                        sci_change_state(&sci_rnc->sm, SCI_RNC_RESUMING);
                else if (dev->dev_type == SATA_DEV || (dev->tproto & SAS_PROTOCOL_STP)) {
                        if (idev->is_direct_attached) {
                                /* @todo Fix this since I am being silly in writing to the STPTLDARNI register. */
                                sci_change_state(&sci_rnc->sm, SCI_RNC_RESUMING);
                        } else {
                                sci_change_state(&sci_rnc->sm, SCI_RNC_INVALIDATING);
                        }
                } else
                        return SCI_FAILURE;
                return SCI_SUCCESS;
        }
        case SCI_RNC_TX_RX_SUSPENDED:
                sci_remote_node_context_setup_to_resume(sci_rnc, cb_fn, cb_p);
                sci_change_state(&sci_rnc->sm, SCI_RNC_RESUMING);
                return SCI_FAILURE_INVALID_STATE;
        case SCI_RNC_AWAIT_SUSPENSION:
                sci_remote_node_context_setup_to_resume(sci_rnc, cb_fn, cb_p);
                return SCI_SUCCESS;
        default:
                dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
                         "%s: invalid state %d\n", __func__, state);
                return SCI_FAILURE_INVALID_STATE;
        }
}

enum sci_status sci_remote_node_context_start_io(struct sci_remote_node_context *sci_rnc,
                                                             struct isci_request *ireq)
{
        enum scis_sds_remote_node_context_states state;

        state = sci_rnc->sm.current_state_id;

        switch (state) {
        case SCI_RNC_READY:
                return SCI_SUCCESS;
        case SCI_RNC_TX_SUSPENDED:
        case SCI_RNC_TX_RX_SUSPENDED:
        case SCI_RNC_AWAIT_SUSPENSION:
                dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
                         "%s: invalid state %d\n", __func__, state);
                return SCI_FAILURE_REMOTE_DEVICE_RESET_REQUIRED;
        default:
                break;
        }
        dev_dbg(scirdev_to_dev(rnc_to_dev(sci_rnc)),
                "%s: requested to start IO while still resuming, %d\n",
                __func__, state);
        return SCI_FAILURE_INVALID_STATE;
}

enum sci_status sci_remote_node_context_start_task(struct sci_remote_node_context *sci_rnc,
                                                        struct isci_request *ireq)
{
        enum scis_sds_remote_node_context_states state;

        state = sci_rnc->sm.current_state_id;
        switch (state) {
        case SCI_RNC_RESUMING:
        case SCI_RNC_READY:
        case SCI_RNC_AWAIT_SUSPENSION:
                return SCI_SUCCESS;
        case SCI_RNC_TX_SUSPENDED:
        case SCI_RNC_TX_RX_SUSPENDED:
                sci_remote_node_context_resume(sci_rnc, NULL, NULL);
                return SCI_SUCCESS;
        default:
                dev_warn(scirdev_to_dev(rnc_to_dev(sci_rnc)),
                         "%s: invalid state %d\n", __func__, state);
                return SCI_FAILURE_INVALID_STATE;
        }
}