libata-acpi.c

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/*
 * libata-acpi.c
 * Provides ACPI support for PATA/SATA.
 *
 * Copyright (C) 2006 Intel Corp.
 * Copyright (C) 2006 Randy Dunlap
 */

#include <linux/module.h>
#include <linux/ata.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/acpi.h>
#include <linux/libata.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/pm_runtime.h>
#include <scsi/scsi_device.h>
#include "libata.h"

#include <acpi/acpi_bus.h>

unsigned int ata_acpi_gtf_filter = ATA_ACPI_FILTER_DEFAULT;
module_param_named(acpi_gtf_filter, ata_acpi_gtf_filter, int, 0644);
MODULE_PARM_DESC(acpi_gtf_filter, "filter mask for ACPI _GTF commands, set to filter out (0x1=set xfermode, 0x2=lock/freeze lock, 0x4=DIPM, 0x8=FPDMA non-zero offset, 0x10=FPDMA DMA Setup FIS auto-activate)");

#define NO_PORT_MULT        0xffff
#define SATA_ADR(root, pmp) (((root) << 16) | (pmp))

#define REGS_PER_GTF        7
struct ata_acpi_gtf {
    u8  tf[REGS_PER_GTF];   /* regs. 0x1f1 - 0x1f7 */
} __packed;

/*
 *  Helper - belongs in the PCI layer somewhere eventually
 */
static int is_pci_dev(struct device *dev)
{
    return (dev->bus == &pci_bus_type);
}

static void ata_acpi_clear_gtf(struct ata_device *dev)
{
    kfree(dev->gtf_cache);
    dev->gtf_cache = NULL;
}

acpi_handle ata_ap_acpi_handle(struct ata_port *ap)
{
    if (ap->flags & ATA_FLAG_ACPI_SATA)
        return NULL;

    return acpi_get_child(DEVICE_ACPI_HANDLE(ap->host->dev), ap->port_no);
}
EXPORT_SYMBOL(ata_ap_acpi_handle);

acpi_handle ata_dev_acpi_handle(struct ata_device *dev)
{
    acpi_integer adr;
    struct ata_port *ap = dev->link->ap;

    if (ap->flags & ATA_FLAG_ACPI_SATA) {
        if (!sata_pmp_attached(ap))
            adr = SATA_ADR(ap->port_no, NO_PORT_MULT);
        else
            adr = SATA_ADR(ap->port_no, dev->link->pmp);
        return acpi_get_child(DEVICE_ACPI_HANDLE(ap->host->dev), adr);
    } else
        return acpi_get_child(ata_ap_acpi_handle(ap), dev->devno);
}
EXPORT_SYMBOL(ata_dev_acpi_handle);

/* @ap and @dev are the same as ata_acpi_handle_hotplug() */
static void ata_acpi_detach_device(struct ata_port *ap, struct ata_device *dev)
{
    if (dev)
        dev->flags |= ATA_DFLAG_DETACH;
    else {
        struct ata_link *tlink;
        struct ata_device *tdev;

        ata_for_each_link(tlink, ap, EDGE)
            ata_for_each_dev(tdev, tlink, ALL)
                tdev->flags |= ATA_DFLAG_DETACH;
    }

    ata_port_schedule_eh(ap);
}

static void ata_acpi_handle_hotplug(struct ata_port *ap, struct ata_device *dev,
                    u32 event)
{
    struct ata_eh_info *ehi = &ap->link.eh_info;
    int wait = 0;
    unsigned long flags;

    spin_lock_irqsave(ap->lock, flags);
    /*
     * When dock driver calls into the routine, it will always use
     * ACPI_NOTIFY_BUS_CHECK/ACPI_NOTIFY_DEVICE_CHECK for add and
     * ACPI_NOTIFY_EJECT_REQUEST for remove
     */
    switch (event) {
    case ACPI_NOTIFY_BUS_CHECK:
    case ACPI_NOTIFY_DEVICE_CHECK:
        ata_ehi_push_desc(ehi, "ACPI event");

        ata_ehi_hotplugged(ehi);
        ata_port_freeze(ap);
        break;
    case ACPI_NOTIFY_EJECT_REQUEST:
        ata_ehi_push_desc(ehi, "ACPI event");

        ata_acpi_detach_device(ap, dev);
        wait = 1;
        break;
    }

    spin_unlock_irqrestore(ap->lock, flags);

    if (wait)
        ata_port_wait_eh(ap);
}

static void ata_acpi_dev_notify_dock(acpi_handle handle, u32 event, void *data)
{
    struct ata_device *dev = data;

    ata_acpi_handle_hotplug(dev->link->ap, dev, event);
}

static void ata_acpi_ap_notify_dock(acpi_handle handle, u32 event, void *data)
{
    struct ata_port *ap = data;

    ata_acpi_handle_hotplug(ap, NULL, event);
}

static void ata_acpi_uevent(struct ata_port *ap, struct ata_device *dev,
    u32 event)
{
    struct kobject *kobj = NULL;
    char event_string[20];
    char *envp[] = { event_string, NULL };

    if (dev) {
        if (dev->sdev)
            kobj = &dev->sdev->sdev_gendev.kobj;
    } else
        kobj = &ap->dev->kobj;

    if (kobj) {
        snprintf(event_string, 20, "BAY_EVENT=%d", event);
        kobject_uevent_env(kobj, KOBJ_CHANGE, envp);
    }
}

static void ata_acpi_ap_uevent(acpi_handle handle, u32 event, void *data)
{
    ata_acpi_uevent(data, NULL, event);
}

static void ata_acpi_dev_uevent(acpi_handle handle, u32 event, void *data)
{
    struct ata_device *dev = data;
    ata_acpi_uevent(dev->link->ap, dev, event);
}

static const struct acpi_dock_ops ata_acpi_dev_dock_ops = {
    .handler = ata_acpi_dev_notify_dock,
    .uevent = ata_acpi_dev_uevent,
};

static const struct acpi_dock_ops ata_acpi_ap_dock_ops = {
    .handler = ata_acpi_ap_notify_dock,
    .uevent = ata_acpi_ap_uevent,
};

void ata_acpi_dissociate(struct ata_host *host)
{
    int i;

    /* Restore initial _GTM values so that driver which attaches
     * afterward can use them too.
     */
    for (i = 0; i < host->n_ports; i++) {
        struct ata_port *ap = host->ports[i];
        const struct ata_acpi_gtm *gtm = ata_acpi_init_gtm(ap);

        if (ata_ap_acpi_handle(ap) && gtm)
            ata_acpi_stm(ap, gtm);
    }
}

int ata_acpi_gtm(struct ata_port *ap, struct ata_acpi_gtm *gtm)
{
    struct acpi_buffer output = { .length = ACPI_ALLOCATE_BUFFER };
    union acpi_object *out_obj;
    acpi_status status;
    int rc = 0;

    status = acpi_evaluate_object(ata_ap_acpi_handle(ap), "_GTM", NULL,
                      &output);

    rc = -ENOENT;
    if (status == AE_NOT_FOUND)
        goto out_free;

    rc = -EINVAL;
    if (ACPI_FAILURE(status)) {
        ata_port_err(ap, "ACPI get timing mode failed (AE 0x%x)\n",
                 status);
        goto out_free;
    }

    out_obj = output.pointer;
    if (out_obj->type != ACPI_TYPE_BUFFER) {
        ata_port_warn(ap, "_GTM returned unexpected object type 0x%x\n",
                  out_obj->type);

        goto out_free;
    }

    if (out_obj->buffer.length != sizeof(struct ata_acpi_gtm)) {
        ata_port_err(ap, "_GTM returned invalid length %d\n",
                 out_obj->buffer.length);
        goto out_free;
    }

    memcpy(gtm, out_obj->buffer.pointer, sizeof(struct ata_acpi_gtm));
    rc = 0;
 out_free:
    kfree(output.pointer);
    return rc;
}

EXPORT_SYMBOL_GPL(ata_acpi_gtm);

int ata_acpi_stm(struct ata_port *ap, const struct ata_acpi_gtm *stm)
{
    acpi_status status;
    struct ata_acpi_gtm     stm_buf = *stm;
    struct acpi_object_list         input;
    union acpi_object               in_params[3];

    in_params[0].type = ACPI_TYPE_BUFFER;
    in_params[0].buffer.length = sizeof(struct ata_acpi_gtm);
    in_params[0].buffer.pointer = (u8 *)&stm_buf;
    /* Buffers for id may need byteswapping ? */
    in_params[1].type = ACPI_TYPE_BUFFER;
    in_params[1].buffer.length = 512;
    in_params[1].buffer.pointer = (u8 *)ap->link.device[0].id;
    in_params[2].type = ACPI_TYPE_BUFFER;
    in_params[2].buffer.length = 512;
    in_params[2].buffer.pointer = (u8 *)ap->link.device[1].id;

    input.count = 3;
    input.pointer = in_params;

    status = acpi_evaluate_object(ata_ap_acpi_handle(ap), "_STM", &input,
                      NULL);

    if (status == AE_NOT_FOUND)
        return -ENOENT;
    if (ACPI_FAILURE(status)) {
        ata_port_err(ap, "ACPI set timing mode failed (status=0x%x)\n",
                 status);
        return -EINVAL;
    }
    return 0;
}

EXPORT_SYMBOL_GPL(ata_acpi_stm);

static int ata_dev_get_GTF(struct ata_device *dev, struct ata_acpi_gtf **gtf)
{
    struct ata_port *ap = dev->link->ap;
    acpi_status status;
    struct acpi_buffer output;
    union acpi_object *out_obj;
    int rc = 0;

    /* if _GTF is cached, use the cached value */
    if (dev->gtf_cache) {
        out_obj = dev->gtf_cache;
        goto done;
    }

    /* set up output buffer */
    output.length = ACPI_ALLOCATE_BUFFER;
    output.pointer = NULL;  /* ACPI-CA sets this; save/free it later */

    if (ata_msg_probe(ap))
        ata_dev_dbg(dev, "%s: ENTER: port#: %d\n",
                __func__, ap->port_no);

    /* _GTF has no input parameters */
    status = acpi_evaluate_object(ata_dev_acpi_handle(dev), "_GTF", NULL,
                      &output);
    out_obj = dev->gtf_cache = output.pointer;

    if (ACPI_FAILURE(status)) {
        if (status != AE_NOT_FOUND) {
            ata_dev_warn(dev, "_GTF evaluation failed (AE 0x%x)\n",
                     status);
            rc = -EINVAL;
        }
        goto out_free;
    }

    if (!output.length || !output.pointer) {
        if (ata_msg_probe(ap))
            ata_dev_dbg(dev, "%s: Run _GTF: length or ptr is NULL (0x%llx, 0x%p)\n",
                    __func__,
                    (unsigned long long)output.length,
                    output.pointer);
        rc = -EINVAL;
        goto out_free;
    }

    if (out_obj->type != ACPI_TYPE_BUFFER) {
        ata_dev_warn(dev, "_GTF unexpected object type 0x%x\n",
                 out_obj->type);
        rc = -EINVAL;
        goto out_free;
    }

    if (out_obj->buffer.length % REGS_PER_GTF) {
        ata_dev_warn(dev, "unexpected _GTF length (%d)\n",
                 out_obj->buffer.length);
        rc = -EINVAL;
        goto out_free;
    }

 done:
    rc = out_obj->buffer.length / REGS_PER_GTF;
    if (gtf) {
        *gtf = (void *)out_obj->buffer.pointer;
        if (ata_msg_probe(ap))
            ata_dev_dbg(dev, "%s: returning gtf=%p, gtf_count=%d\n",
                    __func__, *gtf, rc);
    }
    return rc;

 out_free:
    ata_acpi_clear_gtf(dev);
    return rc;
}

unsigned long ata_acpi_gtm_xfermask(struct ata_device *dev,
                    const struct ata_acpi_gtm *gtm)
{
    unsigned long xfer_mask = 0;
    unsigned int type;
    int unit;
    u8 mode;

    /* we always use the 0 slot for crap hardware */
    unit = dev->devno;
    if (!(gtm->flags & 0x10))
        unit = 0;

    /* PIO */
    mode = ata_timing_cycle2mode(ATA_SHIFT_PIO, gtm->drive[unit].pio);
    xfer_mask |= ata_xfer_mode2mask(mode);

    /* See if we have MWDMA or UDMA data. We don't bother with
     * MWDMA if UDMA is available as this means the BIOS set UDMA
     * and our error changedown if it works is UDMA to PIO anyway.
     */
    if (!(gtm->flags & (1 << (2 * unit))))
        type = ATA_SHIFT_MWDMA;
    else
        type = ATA_SHIFT_UDMA;

    mode = ata_timing_cycle2mode(type, gtm->drive[unit].dma);
    xfer_mask |= ata_xfer_mode2mask(mode);

    return xfer_mask;
}
EXPORT_SYMBOL_GPL(ata_acpi_gtm_xfermask);

int ata_acpi_cbl_80wire(struct ata_port *ap, const struct ata_acpi_gtm *gtm)
{
    struct ata_device *dev;

    ata_for_each_dev(dev, &ap->link, ENABLED) {
        unsigned long xfer_mask, udma_mask;

        xfer_mask = ata_acpi_gtm_xfermask(dev, gtm);
        ata_unpack_xfermask(xfer_mask, NULL, NULL, &udma_mask);

        if (udma_mask & ~ATA_UDMA_MASK_40C)
            return 1;
    }

    return 0;
}
EXPORT_SYMBOL_GPL(ata_acpi_cbl_80wire);

static void ata_acpi_gtf_to_tf(struct ata_device *dev,
                   const struct ata_acpi_gtf *gtf,
                   struct ata_taskfile *tf)
{
    ata_tf_init(dev, tf);

    tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
    tf->protocol = ATA_PROT_NODATA;
    tf->feature = gtf->tf[0];   /* 0x1f1 */
    tf->nsect   = gtf->tf[1];   /* 0x1f2 */
    tf->lbal    = gtf->tf[2];   /* 0x1f3 */
    tf->lbam    = gtf->tf[3];   /* 0x1f4 */
    tf->lbah    = gtf->tf[4];   /* 0x1f5 */
    tf->device  = gtf->tf[5];   /* 0x1f6 */
    tf->command = gtf->tf[6];   /* 0x1f7 */
}

static int ata_acpi_filter_tf(struct ata_device *dev,
                  const struct ata_taskfile *tf,
                  const struct ata_taskfile *ptf)
{
    if (dev->gtf_filter & ATA_ACPI_FILTER_SETXFER) {
        /* libata doesn't use ACPI to configure transfer mode.
         * It will only confuse device configuration.  Skip.
         */
        if (tf->command == ATA_CMD_SET_FEATURES &&
            tf->feature == SETFEATURES_XFER)
            return 1;
    }

    if (dev->gtf_filter & ATA_ACPI_FILTER_LOCK) {
        /* BIOS writers, sorry but we don't wanna lock
         * features unless the user explicitly said so.
         */

        /* DEVICE CONFIGURATION FREEZE LOCK */
        if (tf->command == ATA_CMD_CONF_OVERLAY &&
            tf->feature == ATA_DCO_FREEZE_LOCK)
            return 1;

        /* SECURITY FREEZE LOCK */
        if (tf->command == ATA_CMD_SEC_FREEZE_LOCK)
            return 1;

        /* SET MAX LOCK and SET MAX FREEZE LOCK */
        if ((!ptf || ptf->command != ATA_CMD_READ_NATIVE_MAX) &&
            tf->command == ATA_CMD_SET_MAX &&
            (tf->feature == ATA_SET_MAX_LOCK ||
             tf->feature == ATA_SET_MAX_FREEZE_LOCK))
            return 1;
    }

    if (tf->command == ATA_CMD_SET_FEATURES &&
        tf->feature == SETFEATURES_SATA_ENABLE) {
        /* inhibit enabling DIPM */
        if (dev->gtf_filter & ATA_ACPI_FILTER_DIPM &&
            tf->nsect == SATA_DIPM)
            return 1;

        /* inhibit FPDMA non-zero offset */
        if (dev->gtf_filter & ATA_ACPI_FILTER_FPDMA_OFFSET &&
            (tf->nsect == SATA_FPDMA_OFFSET ||
             tf->nsect == SATA_FPDMA_IN_ORDER))
            return 1;

        /* inhibit FPDMA auto activation */
        if (dev->gtf_filter & ATA_ACPI_FILTER_FPDMA_AA &&
            tf->nsect == SATA_FPDMA_AA)
            return 1;
    }

    return 0;
}

static int ata_acpi_run_tf(struct ata_device *dev,
               const struct ata_acpi_gtf *gtf,
               const struct ata_acpi_gtf *prev_gtf)
{
    struct ata_taskfile *pptf = NULL;
    struct ata_taskfile tf, ptf, rtf;
    unsigned int err_mask;
    const char *level;
    const char *descr;
    char msg[60];
    int rc;

    if ((gtf->tf[0] == 0) && (gtf->tf[1] == 0) && (gtf->tf[2] == 0)
        && (gtf->tf[3] == 0) && (gtf->tf[4] == 0) && (gtf->tf[5] == 0)
        && (gtf->tf[6] == 0))
        return 0;

    ata_acpi_gtf_to_tf(dev, gtf, &tf);
    if (prev_gtf) {
        ata_acpi_gtf_to_tf(dev, prev_gtf, &ptf);
        pptf = &ptf;
    }

    if (!ata_acpi_filter_tf(dev, &tf, pptf)) {
        rtf = tf;
        err_mask = ata_exec_internal(dev, &rtf, NULL,
                         DMA_NONE, NULL, 0, 0);

        switch (err_mask) {
        case 0:
            level = KERN_DEBUG;
            snprintf(msg, sizeof(msg), "succeeded");
            rc = 1;
            break;

        case AC_ERR_DEV:
            level = KERN_INFO;
            snprintf(msg, sizeof(msg),
                 "rejected by device (Stat=0x%02x Err=0x%02x)",
                 rtf.command, rtf.feature);
            rc = 0;
            break;

        default:
            level = KERN_ERR;
            snprintf(msg, sizeof(msg),
                 "failed (Emask=0x%x Stat=0x%02x Err=0x%02x)",
                 err_mask, rtf.command, rtf.feature);
            rc = -EIO;
            break;
        }
    } else {
        level = KERN_INFO;
        snprintf(msg, sizeof(msg), "filtered out");
        rc = 0;
    }
    descr = ata_get_cmd_descript(tf.command);

    ata_dev_printk(dev, level,
               "ACPI cmd %02x/%02x:%02x:%02x:%02x:%02x:%02x (%s) %s\n",
               tf.command, tf.feature, tf.nsect, tf.lbal,
               tf.lbam, tf.lbah, tf.device,
               (descr ? descr : "unknown"), msg);

    return rc;
}

static int ata_acpi_exec_tfs(struct ata_device *dev, int *nr_executed)
{
    struct ata_acpi_gtf *gtf = NULL, *pgtf = NULL;
    int gtf_count, i, rc;

    /* get taskfiles */
    rc = ata_dev_get_GTF(dev, &gtf);
    if (rc < 0)
        return rc;
    gtf_count = rc;

    /* execute them */
    for (i = 0; i < gtf_count; i++, gtf++) {
        rc = ata_acpi_run_tf(dev, gtf, pgtf);
        if (rc < 0)
            break;
        if (rc) {
            (*nr_executed)++;
            pgtf = gtf;
        }
    }

    ata_acpi_clear_gtf(dev);

    if (rc < 0)
        return rc;
    return 0;
}

static int ata_acpi_push_id(struct ata_device *dev)
{
    struct ata_port *ap = dev->link->ap;
    acpi_status status;
    struct acpi_object_list input;
    union acpi_object in_params[1];

    if (ata_msg_probe(ap))
        ata_dev_dbg(dev, "%s: ix = %d, port#: %d\n",
                __func__, dev->devno, ap->port_no);

    /* Give the drive Identify data to the drive via the _SDD method */
    /* _SDD: set up input parameters */
    input.count = 1;
    input.pointer = in_params;
    in_params[0].type = ACPI_TYPE_BUFFER;
    in_params[0].buffer.length = sizeof(dev->id[0]) * ATA_ID_WORDS;
    in_params[0].buffer.pointer = (u8 *)dev->id;
    /* Output buffer: _SDD has no output */

    /* It's OK for _SDD to be missing too. */
    swap_buf_le16(dev->id, ATA_ID_WORDS);
    status = acpi_evaluate_object(ata_dev_acpi_handle(dev), "_SDD", &input,
                      NULL);
    swap_buf_le16(dev->id, ATA_ID_WORDS);

    if (status == AE_NOT_FOUND)
        return -ENOENT;

    if (ACPI_FAILURE(status)) {
        ata_dev_warn(dev, "ACPI _SDD failed (AE 0x%x)\n", status);
        return -EIO;
    }

    return 0;
}

int ata_acpi_on_suspend(struct ata_port *ap)
{
    /* nada */
    return 0;
}

void ata_acpi_on_resume(struct ata_port *ap)
{
    const struct ata_acpi_gtm *gtm = ata_acpi_init_gtm(ap);
    struct ata_device *dev;

    if (ata_ap_acpi_handle(ap) && gtm) {
        /* _GTM valid */

        /* restore timing parameters */
        ata_acpi_stm(ap, gtm);

        /* _GTF should immediately follow _STM so that it can
         * use values set by _STM.  Cache _GTF result and
         * schedule _GTF.
         */
        ata_for_each_dev(dev, &ap->link, ALL) {
            ata_acpi_clear_gtf(dev);
            if (ata_dev_enabled(dev) &&
                ata_dev_get_GTF(dev, NULL) >= 0)
                dev->flags |= ATA_DFLAG_ACPI_PENDING;
        }
    } else {
        /* SATA _GTF needs to be evaulated after _SDD and
         * there's no reason to evaluate IDE _GTF early
         * without _STM.  Clear cache and schedule _GTF.
         */
        ata_for_each_dev(dev, &ap->link, ALL) {
            ata_acpi_clear_gtf(dev);
            if (ata_dev_enabled(dev))
                dev->flags |= ATA_DFLAG_ACPI_PENDING;
        }
    }
}

void ata_acpi_set_state(struct ata_port *ap, pm_message_t state)
{
    struct ata_device *dev;
    acpi_handle handle;
    int acpi_state;

    /* channel first and then drives for power on and vica versa
       for power off */
    handle = ata_ap_acpi_handle(ap);
    if (handle && state.event == PM_EVENT_ON)
        acpi_bus_set_power(handle, ACPI_STATE_D0);

    ata_for_each_dev(dev, &ap->link, ENABLED) {
        handle = ata_dev_acpi_handle(dev);
        if (!handle)
            continue;

        if (state.event != PM_EVENT_ON) {
            acpi_state = acpi_pm_device_sleep_state(
                &dev->sdev->sdev_gendev, NULL, ACPI_STATE_D3);
            if (acpi_state > 0)
                acpi_bus_set_power(handle, acpi_state);
            /* TBD: need to check if it's runtime pm request */
            acpi_pm_device_run_wake(
                &dev->sdev->sdev_gendev, true);
        } else {
            /* Ditto */
            acpi_pm_device_run_wake(
                &dev->sdev->sdev_gendev, false);
            acpi_bus_set_power(handle, ACPI_STATE_D0);
        }
    }

    handle = ata_ap_acpi_handle(ap);
    if (handle && state.event != PM_EVENT_ON)
        acpi_bus_set_power(handle, ACPI_STATE_D3);
}

int ata_acpi_on_devcfg(struct ata_device *dev)
{
    struct ata_port *ap = dev->link->ap;
    struct ata_eh_context *ehc = &ap->link.eh_context;
    int acpi_sata = ap->flags & ATA_FLAG_ACPI_SATA;
    int nr_executed = 0;
    int rc;

    if (!ata_dev_acpi_handle(dev))
        return 0;

    /* do we need to do _GTF? */
    if (!(dev->flags & ATA_DFLAG_ACPI_PENDING) &&
        !(acpi_sata && (ehc->i.flags & ATA_EHI_DID_HARDRESET)))
        return 0;

    /* do _SDD if SATA */
    if (acpi_sata) {
        rc = ata_acpi_push_id(dev);
        if (rc && rc != -ENOENT)
            goto acpi_err;
    }

    /* do _GTF */
    rc = ata_acpi_exec_tfs(dev, &nr_executed);
    if (rc)
        goto acpi_err;

    dev->flags &= ~ATA_DFLAG_ACPI_PENDING;

    /* refresh IDENTIFY page if any _GTF command has been executed */
    if (nr_executed) {
        rc = ata_dev_reread_id(dev, 0);
        if (rc < 0) {
            ata_dev_err(dev,
                    "failed to IDENTIFY after ACPI commands\n");
            return rc;
        }
    }

    return 0;

 acpi_err:
    /* ignore evaluation failure if we can continue safely */
    if (rc == -EINVAL && !nr_executed && !(ap->pflags & ATA_PFLAG_FROZEN))
        return 0;

    /* fail and let EH retry once more for unknown IO errors */
    if (!(dev->flags & ATA_DFLAG_ACPI_FAILED)) {
        dev->flags |= ATA_DFLAG_ACPI_FAILED;
        return rc;
    }

    ata_dev_warn(dev, "ACPI: failed the second time, disabled\n");

    /* We can safely continue if no _GTF command has been executed
     * and port is not frozen.
     */
    if (!nr_executed && !(ap->pflags & ATA_PFLAG_FROZEN))
        return 0;

    return rc;
}

void ata_acpi_on_disable(struct ata_device *dev)
{
    ata_acpi_clear_gtf(dev);
}

static void ata_acpi_wake_dev(acpi_handle handle, u32 event, void *context)
{
    struct ata_device *ata_dev = context;

    if (event == ACPI_NOTIFY_DEVICE_WAKE && ata_dev &&
            pm_runtime_suspended(&ata_dev->sdev->sdev_gendev))
        scsi_autopm_get_device(ata_dev->sdev);
}

static void ata_acpi_add_pm_notifier(struct ata_device *dev)
{
    struct acpi_device *acpi_dev;
    acpi_handle handle;
    acpi_status status;

    handle = ata_dev_acpi_handle(dev);
    if (!handle)
        return;

    status = acpi_bus_get_device(handle, &acpi_dev);
    if (ACPI_FAILURE(status))
        return;

    if (dev->sdev->can_power_off) {
        acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
            ata_acpi_wake_dev, dev);
        device_set_run_wake(&dev->sdev->sdev_gendev, true);
    }
}

static void ata_acpi_remove_pm_notifier(struct ata_device *dev)
{
    struct acpi_device *acpi_dev;
    acpi_handle handle;
    acpi_status status;

    handle = ata_dev_acpi_handle(dev);
    if (!handle)
        return;

    status = acpi_bus_get_device(handle, &acpi_dev);
    if (ACPI_FAILURE(status))
        return;

    if (dev->sdev->can_power_off) {
        device_set_run_wake(&dev->sdev->sdev_gendev, false);
        acpi_remove_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
            ata_acpi_wake_dev);
    }
}

static void ata_acpi_register_power_resource(struct ata_device *dev)
{
    struct scsi_device *sdev = dev->sdev;
    acpi_handle handle;
    struct device *device;

    handle = ata_dev_acpi_handle(dev);
    if (!handle)
        return;

    device = &sdev->sdev_gendev;

    acpi_power_resource_register_device(device, handle);
}

static void ata_acpi_unregister_power_resource(struct ata_device *dev)
{
    struct scsi_device *sdev = dev->sdev;
    acpi_handle handle;
    struct device *device;

    handle = ata_dev_acpi_handle(dev);
    if (!handle)
        return;

    device = &sdev->sdev_gendev;

    acpi_power_resource_unregister_device(device, handle);
}

void ata_acpi_bind(struct ata_device *dev)
{
    ata_acpi_add_pm_notifier(dev);
    ata_acpi_register_power_resource(dev);
}

void ata_acpi_unbind(struct ata_device *dev)
{
    ata_acpi_remove_pm_notifier(dev);
    ata_acpi_unregister_power_resource(dev);
}

static int compat_pci_ata(struct ata_port *ap)
{
    struct device *dev = ap->tdev.parent;
    struct pci_dev *pdev;

    if (!is_pci_dev(dev))
        return 0;

    pdev = to_pci_dev(dev);

    if ((pdev->class >> 8) != PCI_CLASS_STORAGE_SATA &&
        (pdev->class >> 8) != PCI_CLASS_STORAGE_IDE)
        return 0;

    return 1;
}

static int ata_acpi_bind_host(struct ata_port *ap, acpi_handle *handle)
{
    if (ap->flags & ATA_FLAG_ACPI_SATA)
        return -ENODEV;

    *handle = acpi_get_child(DEVICE_ACPI_HANDLE(ap->tdev.parent),
            ap->port_no);

    if (!*handle)
        return -ENODEV;

    if (ata_acpi_gtm(ap, &ap->__acpi_init_gtm) == 0)
        ap->pflags |= ATA_PFLAG_INIT_GTM_VALID;

    return 0;
}

static int ata_acpi_bind_device(struct ata_port *ap, struct scsi_device *sdev,
                acpi_handle *handle)
{
    struct ata_device *ata_dev;
    acpi_status status;
    struct acpi_device *acpi_dev;
    struct acpi_device_power_state *states;

    if (ap->flags & ATA_FLAG_ACPI_SATA) {
        if (!sata_pmp_attached(ap))
            ata_dev = &ap->link.device[sdev->id];
        else
            ata_dev = &ap->pmp_link[sdev->channel].device[sdev->id];
    }
    else {
        ata_dev = &ap->link.device[sdev->id];
    }

    *handle = ata_dev_acpi_handle(ata_dev);

    if (!*handle)
        return -ENODEV;

    status = acpi_bus_get_device(*handle, &acpi_dev);
    if (ACPI_FAILURE(status))
        return 0;

    /*
     * If firmware has _PS3 or _PR3 for this device,
     * and this ata ODD device support device attention,
     * it means this device can be powered off
     */
    states = acpi_dev->power.states;
    if ((states[ACPI_STATE_D3_HOT].flags.valid ||
            states[ACPI_STATE_D3_COLD].flags.explicit_set) &&
            ata_dev->flags & ATA_DFLAG_DA)
        sdev->can_power_off = 1;

    return 0;
}

static int is_ata_port(const struct device *dev)
{
    return dev->type == &ata_port_type;
}

static struct ata_port *dev_to_ata_port(struct device *dev)
{
    while (!is_ata_port(dev)) {
        if (!dev->parent)
            return NULL;
        dev = dev->parent;
    }
    return to_ata_port(dev);
}

static int ata_acpi_find_device(struct device *dev, acpi_handle *handle)
{
    struct ata_port *ap = dev_to_ata_port(dev);

    if (!ap)
        return -ENODEV;

    if (!compat_pci_ata(ap))
        return -ENODEV;

    if (scsi_is_host_device(dev))
        return ata_acpi_bind_host(ap, handle);
    else if (scsi_is_sdev_device(dev)) {
        struct scsi_device *sdev = to_scsi_device(dev);

        return ata_acpi_bind_device(ap, sdev, handle);
    } else
        return -ENODEV;
}

static int ata_acpi_find_dummy(struct device *dev, acpi_handle *handle)
{
    return -ENODEV;
}

static struct acpi_bus_type ata_acpi_bus = {
    .find_bridge = ata_acpi_find_dummy,
    .find_device = ata_acpi_find_device,
};

int ata_acpi_register(void)
{
    return scsi_register_acpi_bus_type(&ata_acpi_bus);
}

void ata_acpi_unregister(void)
{
    scsi_unregister_acpi_bus_type(&ata_acpi_bus);
}