/*
 * Support for SATA devices on Serial Attached SCSI (SAS) controllers
 *
 * Copyright (C) 2006 IBM Corporation
 *
 * Written by: Darrick J. Wong <djwong@us.ibm.com>, IBM Corporation
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307
 * USA
 */

#include <linux/scatterlist.h>
#include <linux/slab.h>

#include <scsi/sas_ata.h>
#include "sas_internal.h"
#include <scsi/scsi_host.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_tcq.h>
#include <scsi/scsi.h>
#include <scsi/scsi_transport.h>
#include <scsi/scsi_transport_sas.h>
#include "../scsi_sas_internal.h"
#include "../scsi_transport_api.h"
#include <scsi/scsi_eh.h>

static enum ata_completion_errors sas_to_ata_err(struct task_status_struct *ts)
{
        /* Cheesy attempt to translate SAS errors into ATA.  Hah! */

        /* transport error */
        if (ts->resp == SAS_TASK_UNDELIVERED)
                return AC_ERR_ATA_BUS;

        /* ts->resp == SAS_TASK_COMPLETE */
        /* task delivered, what happened afterwards? */
        switch (ts->stat) {
                case SAS_DEV_NO_RESPONSE:
                        return AC_ERR_TIMEOUT;

                case SAS_INTERRUPTED:
                case SAS_PHY_DOWN:
                case SAS_NAK_R_ERR:
                        return AC_ERR_ATA_BUS;


                case SAS_DATA_UNDERRUN:
                        /*
                         * Some programs that use the taskfile interface
                         * (smartctl in particular) can cause underrun
                         * problems.  Ignore these errors, perhaps at our
                         * peril.
                         */
                        return 0;

                case SAS_DATA_OVERRUN:
                case SAS_QUEUE_FULL:
                case SAS_DEVICE_UNKNOWN:
                case SAS_SG_ERR:
                        return AC_ERR_INVALID;

                case SAS_OPEN_TO:
                case SAS_OPEN_REJECT:
                        SAS_DPRINTK("%s: Saw error %d.  What to do?\n",
                                    __func__, ts->stat);
                        return AC_ERR_OTHER;

                case SAM_STAT_CHECK_CONDITION:
                case SAS_ABORTED_TASK:
                        return AC_ERR_DEV;

                case SAS_PROTO_RESPONSE:
                        /* This means the ending_fis has the error
                         * value; return 0 here to collect it */
                        return 0;
                default:
                        return 0;
        }
}

static void sas_ata_task_done(struct sas_task *task)
{
        struct ata_queued_cmd *qc = task->uldd_task;
        struct domain_device *dev;
        struct task_status_struct *stat = &task->task_status;
        struct ata_task_resp *resp = (struct ata_task_resp *)stat->buf;
        struct sas_ha_struct *sas_ha;
        enum ata_completion_errors ac;
        unsigned long flags;
        struct ata_link *link;

        if (!qc)
                goto qc_already_gone;

        dev = qc->ap->private_data;
        sas_ha = dev->port->ha;
        link = &dev->sata_dev.ap->link;

        spin_lock_irqsave(dev->sata_dev.ap->lock, flags);
        if (stat->stat == SAS_PROTO_RESPONSE || stat->stat == SAM_STAT_GOOD ||
            ((stat->stat == SAM_STAT_CHECK_CONDITION &&
              dev->sata_dev.command_set == ATAPI_COMMAND_SET))) {
                ata_tf_from_fis(resp->ending_fis, &dev->sata_dev.tf);

                if (!link->sactive) {
                        qc->err_mask |= ac_err_mask(dev->sata_dev.tf.command);
                } else {
                        link->eh_info.err_mask |= ac_err_mask(dev->sata_dev.tf.command);
                        if (unlikely(link->eh_info.err_mask))
                                qc->flags |= ATA_QCFLAG_FAILED;
                }

                dev->sata_dev.sstatus = resp->sstatus;
                dev->sata_dev.serror = resp->serror;
                dev->sata_dev.scontrol = resp->scontrol;
        } else {
                ac = sas_to_ata_err(stat);
                if (ac) {
                        SAS_DPRINTK("%s: SAS error %x\n", __func__,
                                    stat->stat);
                        /* We saw a SAS error. Send a vague error. */
                        if (!link->sactive) {
                                qc->err_mask = ac;
                        } else {
                                link->eh_info.err_mask |= AC_ERR_DEV;
                                qc->flags |= ATA_QCFLAG_FAILED;
                        }

                        dev->sata_dev.tf.feature = 0x04; /* status err */
                        dev->sata_dev.tf.command = ATA_ERR;
                }
        }

        qc->lldd_task = NULL;
        if (qc->scsicmd)
                ASSIGN_SAS_TASK(qc->scsicmd, NULL);
        ata_qc_complete(qc);
        spin_unlock_irqrestore(dev->sata_dev.ap->lock, flags);

        /*
         * If the sas_task has an ata qc, a scsi_cmnd and the aborted
         * flag is set, then we must have come in via the libsas EH
         * functions.  When we exit this function, we need to put the
         * scsi_cmnd on the list of finished errors.  The ata_qc_complete
         * call cleans up the libata side of things but we're protected
         * from the scsi_cmnd going away because the scsi_cmnd is owned
         * by the EH, making libata's call to scsi_done a NOP.
         */
        spin_lock_irqsave(&task->task_state_lock, flags);
        if (qc->scsicmd && task->task_state_flags & SAS_TASK_STATE_ABORTED)
                scsi_eh_finish_cmd(qc->scsicmd, &sas_ha->eh_done_q);
        spin_unlock_irqrestore(&task->task_state_lock, flags);

qc_already_gone:
        list_del_init(&task->list);
        sas_free_task(task);
}

static unsigned int sas_ata_qc_issue(struct ata_queued_cmd *qc)
{
        int res;
        struct sas_task *task;
        struct domain_device *dev = qc->ap->private_data;
        struct sas_ha_struct *sas_ha = dev->port->ha;
        struct Scsi_Host *host = sas_ha->core.shost;
        struct sas_internal *i = to_sas_internal(host->transportt);
        struct scatterlist *sg;
        unsigned int xfer = 0;
        unsigned int si;

        /* If the device fell off, no sense in issuing commands */
        if (dev->gone)
                return AC_ERR_SYSTEM;

        task = sas_alloc_task(GFP_ATOMIC);
        if (!task)
                return AC_ERR_SYSTEM;
        task->dev = dev;
        task->task_proto = SAS_PROTOCOL_STP;
        task->task_done = sas_ata_task_done;

        if (qc->tf.command == ATA_CMD_FPDMA_WRITE ||
            qc->tf.command == ATA_CMD_FPDMA_READ) {
                /* Need to zero out the tag libata assigned us */
                qc->tf.nsect = 0;
        }

        ata_tf_to_fis(&qc->tf, 1, 0, (u8*)&task->ata_task.fis);
        task->uldd_task = qc;
        if (ata_is_atapi(qc->tf.protocol)) {
                memcpy(task->ata_task.atapi_packet, qc->cdb, qc->dev->cdb_len);
                task->total_xfer_len = qc->nbytes;
                task->num_scatter = qc->n_elem;
        } else {
                for_each_sg(qc->sg, sg, qc->n_elem, si)
                        xfer += sg->length;

                task->total_xfer_len = xfer;
                task->num_scatter = si;
        }

        task->data_dir = qc->dma_dir;
        task->scatter = qc->sg;
        task->ata_task.retry_count = 1;
        task->task_state_flags = SAS_TASK_STATE_PENDING;
        qc->lldd_task = task;

        switch (qc->tf.protocol) {
        case ATA_PROT_NCQ:
                task->ata_task.use_ncq = 1;
                /* fall through */
        case ATAPI_PROT_DMA:
        case ATA_PROT_DMA:
                task->ata_task.dma_xfer = 1;
                break;
        }

        if (qc->scsicmd)
                ASSIGN_SAS_TASK(qc->scsicmd, task);

        if (sas_ha->lldd_max_execute_num < 2)
                res = i->dft->lldd_execute_task(task, 1, GFP_ATOMIC);
        else
                res = sas_queue_up(task);

        /* Examine */
        if (res) {
                SAS_DPRINTK("lldd_execute_task returned: %d\n", res);

                if (qc->scsicmd)
                        ASSIGN_SAS_TASK(qc->scsicmd, NULL);
                sas_free_task(task);
                return AC_ERR_SYSTEM;
        }

        return 0;
}

static bool sas_ata_qc_fill_rtf(struct ata_queued_cmd *qc)
{
        struct domain_device *dev = qc->ap->private_data;

        memcpy(&qc->result_tf, &dev->sata_dev.tf, sizeof(qc->result_tf));
        return true;
}

static int sas_ata_hard_reset(struct ata_link *link, unsigned int *class,
                               unsigned long deadline)
{
        struct ata_port *ap = link->ap;
        struct domain_device *dev = ap->private_data;
        struct sas_internal *i =
                to_sas_internal(dev->port->ha->core.shost->transportt);
        int res = TMF_RESP_FUNC_FAILED;
        int ret = 0;

        if (i->dft->lldd_I_T_nexus_reset)
                res = i->dft->lldd_I_T_nexus_reset(dev);

        if (res != TMF_RESP_FUNC_COMPLETE) {
                SAS_DPRINTK("%s: Unable to reset I T nexus?\n", __func__);
                ret = -EAGAIN;
        }

        switch (dev->sata_dev.command_set) {
                case ATA_COMMAND_SET:
                        SAS_DPRINTK("%s: Found ATA device.\n", __func__);
                        *class = ATA_DEV_ATA;
                        break;
                case ATAPI_COMMAND_SET:
                        SAS_DPRINTK("%s: Found ATAPI device.\n", __func__);
                        *class = ATA_DEV_ATAPI;
                        break;
                default:
                        SAS_DPRINTK("%s: Unknown SATA command set: %d.\n",
                                    __func__,
                                    dev->sata_dev.command_set);
                        *class = ATA_DEV_UNKNOWN;
                        break;
        }

        ap->cbl = ATA_CBL_SATA;
        return ret;
}

static int sas_ata_soft_reset(struct ata_link *link, unsigned int *class,
                               unsigned long deadline)
{
        struct ata_port *ap = link->ap;
        struct domain_device *dev = ap->private_data;
        struct sas_internal *i =
                to_sas_internal(dev->port->ha->core.shost->transportt);
        int res = TMF_RESP_FUNC_FAILED;
        int ret = 0;

        if (i->dft->lldd_ata_soft_reset)
                res = i->dft->lldd_ata_soft_reset(dev);

        if (res != TMF_RESP_FUNC_COMPLETE) {
                SAS_DPRINTK("%s: Unable to soft reset\n", __func__);
                ret = -EAGAIN;
        }

        switch (dev->sata_dev.command_set) {
        case ATA_COMMAND_SET:
                SAS_DPRINTK("%s: Found ATA device.\n", __func__);
                *class = ATA_DEV_ATA;
                break;
        case ATAPI_COMMAND_SET:
                SAS_DPRINTK("%s: Found ATAPI device.\n", __func__);
                *class = ATA_DEV_ATAPI;
                break;
        default:
                SAS_DPRINTK("%s: Unknown SATA command set: %d.\n",
                            __func__, dev->sata_dev.command_set);
                *class = ATA_DEV_UNKNOWN;
                break;
        }

        ap->cbl = ATA_CBL_SATA;
        return ret;
}

static void sas_ata_post_internal(struct ata_queued_cmd *qc)
{
        if (qc->flags & ATA_QCFLAG_FAILED)
                qc->err_mask |= AC_ERR_OTHER;

        if (qc->err_mask) {
                /*
                 * Find the sas_task and kill it.  By this point,
                 * libata has decided to kill the qc, so we needn't
                 * bother with sas_ata_task_done.  But we still
                 * ought to abort the task.
                 */
                struct sas_task *task = qc->lldd_task;
                unsigned long flags;

                qc->lldd_task = NULL;
                if (task) {
                        /* Should this be a AT(API) device reset? */
                        spin_lock_irqsave(&task->task_state_lock, flags);
                        task->task_state_flags |= SAS_TASK_NEED_DEV_RESET;
                        spin_unlock_irqrestore(&task->task_state_lock, flags);

                        task->uldd_task = NULL;
                        __sas_task_abort(task);
                }
        }
}

static struct ata_port_operations sas_sata_ops = {
        .prereset               = ata_std_prereset,
        .softreset              = sas_ata_soft_reset,
        .hardreset              = sas_ata_hard_reset,
        .postreset              = ata_std_postreset,
        .error_handler          = ata_std_error_handler,
        .post_internal_cmd      = sas_ata_post_internal,
        .qc_defer               = ata_std_qc_defer,
        .qc_prep                = ata_noop_qc_prep,
        .qc_issue               = sas_ata_qc_issue,
        .qc_fill_rtf            = sas_ata_qc_fill_rtf,
        .port_start             = ata_sas_port_start,
        .port_stop              = ata_sas_port_stop,
};

static struct ata_port_info sata_port_info = {
        .flags = ATA_FLAG_SATA | ATA_FLAG_PIO_DMA | ATA_FLAG_NCQ,
        .pio_mask = ATA_PIO4,
        .mwdma_mask = ATA_MWDMA2,
        .udma_mask = ATA_UDMA6,
        .port_ops = &sas_sata_ops
};

int sas_ata_init_host_and_port(struct domain_device *found_dev,
                               struct scsi_target *starget)
{
        struct Scsi_Host *shost = dev_to_shost(&starget->dev);
        struct sas_ha_struct *ha = SHOST_TO_SAS_HA(shost);
        struct ata_port *ap;

        ata_host_init(&found_dev->sata_dev.ata_host,
                      ha->dev,
                      sata_port_info.flags,
                      &sas_sata_ops);
        ap = ata_sas_port_alloc(&found_dev->sata_dev.ata_host,
                                &sata_port_info,
                                shost);
        if (!ap) {
                SAS_DPRINTK("ata_sas_port_alloc failed.\n");
                return -ENODEV;
        }

        ap->private_data = found_dev;
        ap->cbl = ATA_CBL_SATA;
        ap->scsi_host = shost;
        found_dev->sata_dev.ap = ap;

        return 0;
}

void sas_ata_task_abort(struct sas_task *task)
{
        struct ata_queued_cmd *qc = task->uldd_task;
        struct completion *waiting;

        /* Bounce SCSI-initiated commands to the SCSI EH */
        if (qc->scsicmd) {
                struct request_queue *q = qc->scsicmd->device->request_queue;
                unsigned long flags;

                spin_lock_irqsave(q->queue_lock, flags);
                blk_abort_request(qc->scsicmd->request);
                spin_unlock_irqrestore(q->queue_lock, flags);
                scsi_schedule_eh(qc->scsicmd->device->host);
                return;
        }

        /* Internal command, fake a timeout and complete. */
        qc->flags &= ~ATA_QCFLAG_ACTIVE;
        qc->flags |= ATA_QCFLAG_FAILED;
        qc->err_mask |= AC_ERR_TIMEOUT;
        waiting = qc->private_data;
        complete(waiting);
}

static void sas_task_timedout(unsigned long _task)
{
        struct sas_task *task = (void *) _task;
        unsigned long flags;

        spin_lock_irqsave(&task->task_state_lock, flags);
        if (!(task->task_state_flags & SAS_TASK_STATE_DONE))
                task->task_state_flags |= SAS_TASK_STATE_ABORTED;
        spin_unlock_irqrestore(&task->task_state_lock, flags);

        complete(&task->completion);
}

static void sas_disc_task_done(struct sas_task *task)
{
        if (!del_timer(&task->timer))
                return;
        complete(&task->completion);
}

#define SAS_DEV_TIMEOUT 10

/**
 * sas_execute_task -- Basic task processing for discovery
 * @task: the task to be executed
 * @buffer: pointer to buffer to do I/O
 * @size: size of @buffer
 * @dma_dir: DMA direction.  DMA_xxx
 */
static int sas_execute_task(struct sas_task *task, void *buffer, int size,
                            enum dma_data_direction dma_dir)
{
        int res = 0;
        struct scatterlist *scatter = NULL;
        struct task_status_struct *ts = &task->task_status;
        int num_scatter = 0;
        int retries = 0;
        struct sas_internal *i =
                to_sas_internal(task->dev->port->ha->core.shost->transportt);

        if (dma_dir != DMA_NONE) {
                scatter = kzalloc(sizeof(*scatter), GFP_KERNEL);
                if (!scatter)
                        goto out;

                sg_init_one(scatter, buffer, size);
                num_scatter = 1;
        }

        task->task_proto = task->dev->tproto;
        task->scatter = scatter;
        task->num_scatter = num_scatter;
        task->total_xfer_len = size;
        task->data_dir = dma_dir;
        task->task_done = sas_disc_task_done;
        if (dma_dir != DMA_NONE &&
            sas_protocol_ata(task->task_proto)) {
                task->num_scatter = dma_map_sg(task->dev->port->ha->dev,
                                               task->scatter,
                                               task->num_scatter,
                                               task->data_dir);
        }

        for (retries = 0; retries < 5; retries++) {
                task->task_state_flags = SAS_TASK_STATE_PENDING;
                init_completion(&task->completion);

                task->timer.data = (unsigned long) task;
                task->timer.function = sas_task_timedout;
                task->timer.expires = jiffies + SAS_DEV_TIMEOUT*HZ;
                add_timer(&task->timer);

                res = i->dft->lldd_execute_task(task, 1, GFP_KERNEL);
                if (res) {
                        del_timer(&task->timer);
                        SAS_DPRINTK("executing SAS discovery task failed:%d\n",
                                    res);
                        goto ex_err;
                }
                wait_for_completion(&task->completion);
                res = -ECOMM;
                if (task->task_state_flags & SAS_TASK_STATE_ABORTED) {
                        int res2;
                        SAS_DPRINTK("task aborted, flags:0x%x\n",
                                    task->task_state_flags);
                        res2 = i->dft->lldd_abort_task(task);
                        SAS_DPRINTK("came back from abort task\n");
                        if (!(task->task_state_flags & SAS_TASK_STATE_DONE)) {
                                if (res2 == TMF_RESP_FUNC_COMPLETE)
                                        continue; /* Retry the task */
                                else
                                        goto ex_err;
                        }
                }
                if (task->task_status.stat == SAM_STAT_BUSY ||
                           task->task_status.stat == SAM_STAT_TASK_SET_FULL ||
                           task->task_status.stat == SAS_QUEUE_FULL) {
                        SAS_DPRINTK("task: q busy, sleeping...\n");
                        schedule_timeout_interruptible(HZ);
                } else if (task->task_status.stat == SAM_STAT_CHECK_CONDITION) {
                        struct scsi_sense_hdr shdr;

                        if (!scsi_normalize_sense(ts->buf, ts->buf_valid_size,
                                                  &shdr)) {
                                SAS_DPRINTK("couldn't normalize sense\n");
                                continue;
                        }
                        if ((shdr.sense_key == 6 && shdr.asc == 0x29) ||
                            (shdr.sense_key == 2 && shdr.asc == 4 &&
                             shdr.ascq == 1)) {
                                SAS_DPRINTK("device %016llx LUN: %016llx "
                                            "powering up or not ready yet, "
                                            "sleeping...\n",
                                            SAS_ADDR(task->dev->sas_addr),
                                            SAS_ADDR(task->ssp_task.LUN));

                                schedule_timeout_interruptible(5*HZ);
                        } else if (shdr.sense_key == 1) {
                                res = 0;
                                break;
                        } else if (shdr.sense_key == 5) {
                                break;
                        } else {
                                SAS_DPRINTK("dev %016llx LUN: %016llx "
                                            "sense key:0x%x ASC:0x%x ASCQ:0x%x"
                                            "\n",
                                            SAS_ADDR(task->dev->sas_addr),
                                            SAS_ADDR(task->ssp_task.LUN),
                                            shdr.sense_key,
                                            shdr.asc, shdr.ascq);
                        }
                } else if (task->task_status.resp != SAS_TASK_COMPLETE ||
                           task->task_status.stat != SAM_STAT_GOOD) {
                        SAS_DPRINTK("task finished with resp:0x%x, "
                                    "stat:0x%x\n",
                                    task->task_status.resp,
                                    task->task_status.stat);
                        goto ex_err;
                } else {
                        res = 0;
                        break;
                }
        }
ex_err:
        if (dma_dir != DMA_NONE) {
                if (sas_protocol_ata(task->task_proto))
                        dma_unmap_sg(task->dev->port->ha->dev,
                                     task->scatter, task->num_scatter,
                                     task->data_dir);
                kfree(scatter);
        }
out:
        return res;
}

/* ---------- SATA ---------- */

static void sas_get_ata_command_set(struct domain_device *dev)
{
        struct dev_to_host_fis *fis =
                (struct dev_to_host_fis *) dev->frame_rcvd;

        if ((fis->sector_count == 1 && /* ATA */
             fis->lbal         == 1 &&
             fis->lbam         == 0 &&
             fis->lbah         == 0 &&
             fis->device       == 0)
            ||
            (fis->sector_count == 0 && /* CE-ATA (mATA) */
             fis->lbal         == 0 &&
             fis->lbam         == 0xCE &&
             fis->lbah         == 0xAA &&
             (fis->device & ~0x10) == 0))

                dev->sata_dev.command_set = ATA_COMMAND_SET;

        else if ((fis->interrupt_reason == 1 && /* ATAPI */
                  fis->lbal             == 1 &&
                  fis->byte_count_low   == 0x14 &&
                  fis->byte_count_high  == 0xEB &&
                  (fis->device & ~0x10) == 0))

                dev->sata_dev.command_set = ATAPI_COMMAND_SET;

        else if ((fis->sector_count == 1 && /* SEMB */
                  fis->lbal         == 1 &&
                  fis->lbam         == 0x3C &&
                  fis->lbah         == 0xC3 &&
                  fis->device       == 0)
                ||
                 (fis->interrupt_reason == 1 && /* SATA PM */
                  fis->lbal             == 1 &&
                  fis->byte_count_low   == 0x69 &&
                  fis->byte_count_high  == 0x96 &&
                  (fis->device & ~0x10) == 0))

                /* Treat it as a superset? */
                dev->sata_dev.command_set = ATAPI_COMMAND_SET;
}

/**
 * sas_issue_ata_cmd -- Basic SATA command processing for discovery
 * @dev: the device to send the command to
 * @command: the command register
 * @features: the features register
 * @buffer: pointer to buffer to do I/O
 * @size: size of @buffer
 * @dma_dir: DMA direction.  DMA_xxx
 */
static int sas_issue_ata_cmd(struct domain_device *dev, u8 command,
                             u8 features, void *buffer, int size,
                             enum dma_data_direction dma_dir)
{
        int res = 0;
        struct sas_task *task;
        struct dev_to_host_fis *d2h_fis = (struct dev_to_host_fis *)
                &dev->frame_rcvd[0];

        res = -ENOMEM;
        task = sas_alloc_task(GFP_KERNEL);
        if (!task)
                goto out;

        task->dev = dev;

        task->ata_task.fis.fis_type = 0x27;
        task->ata_task.fis.command = command;
        task->ata_task.fis.features = features;
        task->ata_task.fis.device = d2h_fis->device;
        task->ata_task.retry_count = 1;

        res = sas_execute_task(task, buffer, size, dma_dir);

        sas_free_task(task);
out:
        return res;
}

#define ATA_IDENTIFY_DEV         0xEC
#define ATA_IDENTIFY_PACKET_DEV  0xA1
#define ATA_SET_FEATURES         0xEF
#define ATA_FEATURE_PUP_STBY_SPIN_UP 0x07

/**
 * sas_discover_sata_dev -- discover a STP/SATA device (SATA_DEV)
 * @dev: STP/SATA device of interest (ATA/ATAPI)
 *
 * The LLDD has already been notified of this device, so that we can
 * send FISes to it.  Here we try to get IDENTIFY DEVICE or IDENTIFY
 * PACKET DEVICE, if ATAPI device, so that the LLDD can fine-tune its
 * performance for this device.
 */
static int sas_discover_sata_dev(struct domain_device *dev)
{
        int     res;
        __le16  *identify_x;
        u8      command;

        identify_x = kzalloc(512, GFP_KERNEL);
        if (!identify_x)
                return -ENOMEM;

        if (dev->sata_dev.command_set == ATA_COMMAND_SET) {
                dev->sata_dev.identify_device = identify_x;
                command = ATA_IDENTIFY_DEV;
        } else {
                dev->sata_dev.identify_packet_device = identify_x;
                command = ATA_IDENTIFY_PACKET_DEV;
        }

        res = sas_issue_ata_cmd(dev, command, 0, identify_x, 512,
                                DMA_FROM_DEVICE);
        if (res)
                goto out_err;

        /* lives on the media? */
        if (le16_to_cpu(identify_x[0]) & 4) {
                /* incomplete response */
                SAS_DPRINTK("sending SET FEATURE/PUP_STBY_SPIN_UP to "
                            "dev %llx\n", SAS_ADDR(dev->sas_addr));
                if (!(identify_x[83] & cpu_to_le16(1<<6)))
                        goto cont1;
                res = sas_issue_ata_cmd(dev, ATA_SET_FEATURES,
                                        ATA_FEATURE_PUP_STBY_SPIN_UP,
                                        NULL, 0, DMA_NONE);
                if (res)
                        goto cont1;

                schedule_timeout_interruptible(5*HZ); /* More time? */
                res = sas_issue_ata_cmd(dev, command, 0, identify_x, 512,
                                        DMA_FROM_DEVICE);
                if (res)
                        goto out_err;
        }
cont1:
        /* XXX Hint: register this SATA device with SATL.
           When this returns, dev->sata_dev->lu is alive and
           present.
        sas_satl_register_dev(dev);
        */

        sas_fill_in_rphy(dev, dev->rphy);

        return 0;
out_err:
        dev->sata_dev.identify_packet_device = NULL;
        dev->sata_dev.identify_device = NULL;
        kfree(identify_x);
        return res;
}

static int sas_discover_sata_pm(struct domain_device *dev)
{
        return -ENODEV;
}

/**
 * sas_discover_sata -- discover an STP/SATA domain device
 * @dev: pointer to struct domain_device of interest
 *
 * First we notify the LLDD of this device, so we can send frames to
 * it.  Then depending on the type of device we call the appropriate
 * discover functions.  Once device discover is done, we notify the
 * LLDD so that it can fine-tune its parameters for the device, by
 * removing it and then adding it.  That is, the second time around,
 * the driver would have certain fields, that it is looking at, set.
 * Finally we initialize the kobj so that the device can be added to
 * the system at registration time.  Devices directly attached to a HA
 * port, have no parents.  All other devices do, and should have their
 * "parent" pointer set appropriately before calling this function.
 */
int sas_discover_sata(struct domain_device *dev)
{
        int res;

        sas_get_ata_command_set(dev);

        res = sas_notify_lldd_dev_found(dev);
        if (res)
                return res;

        switch (dev->dev_type) {
        case SATA_DEV:
                res = sas_discover_sata_dev(dev);
                break;
        case SATA_PM:
                res = sas_discover_sata_pm(dev);
                break;
        default:
                break;
        }
        sas_notify_lldd_dev_gone(dev);
        if (!res) {
                sas_notify_lldd_dev_found(dev);
                res = sas_rphy_add(dev->rphy);
        }

        return res;
}

void sas_ata_strategy_handler(struct Scsi_Host *shost)
{
        struct scsi_device *sdev;

        shost_for_each_device(sdev, shost) {
                struct domain_device *ddev = sdev_to_domain_dev(sdev);
                struct ata_port *ap = ddev->sata_dev.ap;

                if (!dev_is_sata(ddev))
                        continue;

                ata_port_printk(ap, KERN_DEBUG, "sas eh calling libata port error handler");
                ata_scsi_port_error_handler(shost, ap);
        }
}

int sas_ata_timed_out(struct scsi_cmnd *cmd, struct sas_task *task,
                      enum blk_eh_timer_return *rtn)
{
        struct domain_device *ddev = cmd_to_domain_dev(cmd);

        if (!dev_is_sata(ddev) || task)
                return 0;

        /* we're a sata device with no task, so this must be a libata
         * eh timeout.  Ideally should hook into libata timeout
         * handling, but there's no point, it just wants to activate
         * the eh thread */
        *rtn = BLK_EH_NOT_HANDLED;
        return 1;
}

int sas_ata_eh(struct Scsi_Host *shost, struct list_head *work_q,
               struct list_head *done_q)
{
        int rtn = 0;
        struct scsi_cmnd *cmd, *n;
        struct ata_port *ap;

        do {
                LIST_HEAD(sata_q);

                ap = NULL;

                list_for_each_entry_safe(cmd, n, work_q, eh_entry) {
                        struct domain_device *ddev = cmd_to_domain_dev(cmd);

                        if (!dev_is_sata(ddev) || TO_SAS_TASK(cmd))
                                continue;
                        if (ap && ap != ddev->sata_dev.ap)
                                continue;
                        ap = ddev->sata_dev.ap;
                        rtn = 1;
                        list_move(&cmd->eh_entry, &sata_q);
                }

                if (!list_empty(&sata_q)) {
                        ata_port_printk(ap, KERN_DEBUG, "sas eh calling libata cmd error handler\n");
                        ata_scsi_cmd_error_handler(shost, ap, &sata_q);
                        /*
                         * ata's error handler may leave the cmd on the list
                         * so make sure they don't remain on a stack list
                         * about to go out of scope.
                         *
                         * This looks strange, since the commands are
                         * now part of no list, but the next error
                         * action will be ata_port_error_handler()
                         * which takes no list and sweeps them up
                         * anyway from the ata tag array.
                         */
                        while (!list_empty(&sata_q))
                                list_del_init(sata_q.next);
                }
        } while (ap);

        return rtn;
}