update feature-removal-schedule.txt to include deprecated functions

[linux-2.6.git] / include / linux / libata.h

/*
 *  Copyright 2003-2005 Red Hat, Inc.  All rights reserved.
 *  Copyright 2003-2005 Jeff Garzik
 *
 *
 *  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, 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; see the file COPYING.  If not, write to
 *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *
 *  libata documentation is available via 'make {ps|pdf}docs',
 *  as Documentation/DocBook/libata.*
 *
 */

#ifndef __LINUX_LIBATA_H__
#define __LINUX_LIBATA_H__

#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/pci.h>
#include <linux/dma-mapping.h>
#include <asm/scatterlist.h>
#include <linux/io.h>
#include <linux/ata.h>
#include <linux/workqueue.h>
#include <scsi/scsi_host.h>
#include <linux/acpi.h>

/*
 * Define if arch has non-standard setup.  This is a _PCI_ standard
 * not a legacy or ISA standard.
 */
#ifdef CONFIG_ATA_NONSTANDARD
#include <asm/libata-portmap.h>
#else
#include <asm-generic/libata-portmap.h>
#endif

/*
 * compile-time options: to be removed as soon as all the drivers are
 * converted to the new debugging mechanism
 */
#undef ATA_DEBUG                /* debugging output */
#undef ATA_VERBOSE_DEBUG        /* yet more debugging output */
#undef ATA_IRQ_TRAP             /* define to ack screaming irqs */
#undef ATA_NDEBUG               /* define to disable quick runtime checks */


/* note: prints function name for you */
#ifdef ATA_DEBUG
#define DPRINTK(fmt, args...) printk(KERN_ERR "%s: " fmt, __FUNCTION__, ## args)
#ifdef ATA_VERBOSE_DEBUG
#define VPRINTK(fmt, args...) printk(KERN_ERR "%s: " fmt, __FUNCTION__, ## args)
#else
#define VPRINTK(fmt, args...)
#endif  /* ATA_VERBOSE_DEBUG */
#else
#define DPRINTK(fmt, args...)
#define VPRINTK(fmt, args...)
#endif  /* ATA_DEBUG */

#define BPRINTK(fmt, args...) if (ap->flags & ATA_FLAG_DEBUGMSG) printk(KERN_ERR "%s: " fmt, __FUNCTION__, ## args)

/* NEW: debug levels */
#define HAVE_LIBATA_MSG 1

enum {
        ATA_MSG_DRV     = 0x0001,
        ATA_MSG_INFO    = 0x0002,
        ATA_MSG_PROBE   = 0x0004,
        ATA_MSG_WARN    = 0x0008,
        ATA_MSG_MALLOC  = 0x0010,
        ATA_MSG_CTL     = 0x0020,
        ATA_MSG_INTR    = 0x0040,
        ATA_MSG_ERR     = 0x0080,
};

#define ata_msg_drv(p)    ((p)->msg_enable & ATA_MSG_DRV)
#define ata_msg_info(p)   ((p)->msg_enable & ATA_MSG_INFO)
#define ata_msg_probe(p)  ((p)->msg_enable & ATA_MSG_PROBE)
#define ata_msg_warn(p)   ((p)->msg_enable & ATA_MSG_WARN)
#define ata_msg_malloc(p) ((p)->msg_enable & ATA_MSG_MALLOC)
#define ata_msg_ctl(p)    ((p)->msg_enable & ATA_MSG_CTL)
#define ata_msg_intr(p)   ((p)->msg_enable & ATA_MSG_INTR)
#define ata_msg_err(p)    ((p)->msg_enable & ATA_MSG_ERR)

static inline u32 ata_msg_init(int dval, int default_msg_enable_bits)
{
        if (dval < 0 || dval >= (sizeof(u32) * 8))
                return default_msg_enable_bits; /* should be 0x1 - only driver info msgs */
        if (!dval)
                return 0;
        return (1 << dval) - 1;
}

/* defines only for the constants which don't work well as enums */
#define ATA_TAG_POISON          0xfafbfcfdU

/* move to PCI layer? */
static inline struct device *pci_dev_to_dev(struct pci_dev *pdev)
{
        return &pdev->dev;
}

enum {
        /* various global constants */
        LIBATA_MAX_PRD          = ATA_MAX_PRD / 2,
        ATA_MAX_PORTS           = 8,
        ATA_DEF_QUEUE           = 1,
        /* tag ATA_MAX_QUEUE - 1 is reserved for internal commands */
        ATA_MAX_QUEUE           = 32,
        ATA_TAG_INTERNAL        = ATA_MAX_QUEUE - 1,
        ATA_MAX_BUS             = 2,
        ATA_DEF_BUSY_WAIT       = 10000,
        ATA_SHORT_PAUSE         = (HZ >> 6) + 1,

        ATA_SHT_EMULATED        = 1,
        ATA_SHT_CMD_PER_LUN     = 1,
        ATA_SHT_THIS_ID         = -1,
        ATA_SHT_USE_CLUSTERING  = 1,

        /* struct ata_device stuff */
        ATA_DFLAG_LBA           = (1 << 0), /* device supports LBA */
        ATA_DFLAG_LBA48         = (1 << 1), /* device supports LBA48 */
        ATA_DFLAG_CDB_INTR      = (1 << 2), /* device asserts INTRQ when ready for CDB */
        ATA_DFLAG_NCQ           = (1 << 3), /* device supports NCQ */
        ATA_DFLAG_FLUSH_EXT     = (1 << 4), /* do FLUSH_EXT instead of FLUSH */
        ATA_DFLAG_CFG_MASK      = (1 << 8) - 1,

        ATA_DFLAG_PIO           = (1 << 8), /* device limited to PIO mode */
        ATA_DFLAG_NCQ_OFF       = (1 << 9), /* device limited to non-NCQ mode */
        ATA_DFLAG_SPUNDOWN      = (1 << 10), /* XXX: for spindown_compat */
        ATA_DFLAG_INIT_MASK     = (1 << 16) - 1,

        ATA_DFLAG_DETACH        = (1 << 16),
        ATA_DFLAG_DETACHED      = (1 << 17),

        ATA_DEV_UNKNOWN         = 0,    /* unknown device */
        ATA_DEV_ATA             = 1,    /* ATA device */
        ATA_DEV_ATA_UNSUP       = 2,    /* ATA device (unsupported) */
        ATA_DEV_ATAPI           = 3,    /* ATAPI device */
        ATA_DEV_ATAPI_UNSUP     = 4,    /* ATAPI device (unsupported) */
        ATA_DEV_NONE            = 5,    /* no device */

        /* struct ata_port flags */
        ATA_FLAG_SLAVE_POSS     = (1 << 0), /* host supports slave dev */
                                            /* (doesn't imply presence) */
        ATA_FLAG_SATA           = (1 << 1),
        ATA_FLAG_NO_LEGACY      = (1 << 2), /* no legacy mode check */
        ATA_FLAG_MMIO           = (1 << 3), /* use MMIO, not PIO */
        ATA_FLAG_SRST           = (1 << 4), /* (obsolete) use ATA SRST, not E.D.D. */
        ATA_FLAG_SATA_RESET     = (1 << 5), /* (obsolete) use COMRESET */
        ATA_FLAG_NO_ATAPI       = (1 << 6), /* No ATAPI support */
        ATA_FLAG_PIO_DMA        = (1 << 7), /* PIO cmds via DMA */
        ATA_FLAG_PIO_LBA48      = (1 << 8), /* Host DMA engine is LBA28 only */
        ATA_FLAG_PIO_POLLING    = (1 << 9), /* use polling PIO if LLD
                                             * doesn't handle PIO interrupts */
        ATA_FLAG_NCQ            = (1 << 10), /* host supports NCQ */
        ATA_FLAG_HRST_TO_RESUME = (1 << 11), /* hardreset to resume phy */
        ATA_FLAG_SKIP_D2H_BSY   = (1 << 12), /* can't wait for the first D2H
                                              * Register FIS clearing BSY */
        ATA_FLAG_DEBUGMSG       = (1 << 13),
        ATA_FLAG_IGN_SIMPLEX    = (1 << 15), /* ignore SIMPLEX */
        ATA_FLAG_NO_IORDY       = (1 << 16), /* controller lacks iordy */
        ATA_FLAG_ACPI_SATA      = (1 << 17), /* need native SATA ACPI layout */

        /* The following flag belongs to ap->pflags but is kept in
         * ap->flags because it's referenced in many LLDs and will be
         * removed in not-too-distant future.
         */
        ATA_FLAG_DISABLED       = (1 << 23), /* port is disabled, ignore it */

        /* bits 24:31 of ap->flags are reserved for LLD specific flags */

        /* struct ata_port pflags */
        ATA_PFLAG_EH_PENDING    = (1 << 0), /* EH pending */
        ATA_PFLAG_EH_IN_PROGRESS = (1 << 1), /* EH in progress */
        ATA_PFLAG_FROZEN        = (1 << 2), /* port is frozen */
        ATA_PFLAG_RECOVERED     = (1 << 3), /* recovery action performed */
        ATA_PFLAG_LOADING       = (1 << 4), /* boot/loading probe */
        ATA_PFLAG_UNLOADING     = (1 << 5), /* module is unloading */
        ATA_PFLAG_SCSI_HOTPLUG  = (1 << 6), /* SCSI hotplug scheduled */
        ATA_PFLAG_INITIALIZING  = (1 << 7), /* being initialized, don't touch */

        ATA_PFLAG_FLUSH_PORT_TASK = (1 << 16), /* flush port task */
        ATA_PFLAG_SUSPENDED     = (1 << 17), /* port is suspended (power) */
        ATA_PFLAG_PM_PENDING    = (1 << 18), /* PM operation pending */

        /* struct ata_queued_cmd flags */
        ATA_QCFLAG_ACTIVE       = (1 << 0), /* cmd not yet ack'd to scsi lyer */
        ATA_QCFLAG_SG           = (1 << 1), /* have s/g table? */
        ATA_QCFLAG_SINGLE       = (1 << 2), /* no s/g, just a single buffer */
        ATA_QCFLAG_DMAMAP       = ATA_QCFLAG_SG | ATA_QCFLAG_SINGLE,
        ATA_QCFLAG_IO           = (1 << 3), /* standard IO command */
        ATA_QCFLAG_RESULT_TF    = (1 << 4), /* result TF requested */

        ATA_QCFLAG_FAILED       = (1 << 16), /* cmd failed and is owned by EH */
        ATA_QCFLAG_SENSE_VALID  = (1 << 17), /* sense data valid */
        ATA_QCFLAG_EH_SCHEDULED = (1 << 18), /* EH scheduled (obsolete) */

        /* host set flags */
        ATA_HOST_SIMPLEX        = (1 << 0),     /* Host is simplex, one DMA channel per host only */
        ATA_HOST_STARTED        = (1 << 1),     /* Host started */

        /* various lengths of time */
        ATA_TMOUT_BOOT          = 30 * HZ,      /* heuristic */
        ATA_TMOUT_BOOT_QUICK    = 7 * HZ,       /* heuristic */
        ATA_TMOUT_INTERNAL      = 30 * HZ,
        ATA_TMOUT_INTERNAL_QUICK = 5 * HZ,

        /* ATA bus states */
        BUS_UNKNOWN             = 0,
        BUS_DMA                 = 1,
        BUS_IDLE                = 2,
        BUS_NOINTR              = 3,
        BUS_NODATA              = 4,
        BUS_TIMER               = 5,
        BUS_PIO                 = 6,
        BUS_EDD                 = 7,
        BUS_IDENTIFY            = 8,
        BUS_PACKET              = 9,

        /* SATA port states */
        PORT_UNKNOWN            = 0,
        PORT_ENABLED            = 1,
        PORT_DISABLED           = 2,

        /* encoding various smaller bitmaps into a single
         * unsigned int bitmap
         */
        ATA_BITS_PIO            = 7,
        ATA_BITS_MWDMA          = 5,
        ATA_BITS_UDMA           = 8,

        ATA_SHIFT_PIO           = 0,
        ATA_SHIFT_MWDMA         = ATA_SHIFT_PIO + ATA_BITS_PIO,
        ATA_SHIFT_UDMA          = ATA_SHIFT_MWDMA + ATA_BITS_MWDMA,

        ATA_MASK_PIO            = ((1 << ATA_BITS_PIO) - 1) << ATA_SHIFT_PIO,
        ATA_MASK_MWDMA          = ((1 << ATA_BITS_MWDMA) - 1) << ATA_SHIFT_MWDMA,
        ATA_MASK_UDMA           = ((1 << ATA_BITS_UDMA) - 1) << ATA_SHIFT_UDMA,

        /* size of buffer to pad xfers ending on unaligned boundaries */
        ATA_DMA_PAD_SZ          = 4,
        ATA_DMA_PAD_BUF_SZ      = ATA_DMA_PAD_SZ * ATA_MAX_QUEUE,

        /* ering size */
        ATA_ERING_SIZE          = 32,

        /* desc_len for ata_eh_info and context */
        ATA_EH_DESC_LEN         = 80,

        /* reset / recovery action types */
        ATA_EH_REVALIDATE       = (1 << 0),
        ATA_EH_SOFTRESET        = (1 << 1),
        ATA_EH_HARDRESET        = (1 << 2),

        ATA_EH_RESET_MASK       = ATA_EH_SOFTRESET | ATA_EH_HARDRESET,
        ATA_EH_PERDEV_MASK      = ATA_EH_REVALIDATE,

        /* ata_eh_info->flags */
        ATA_EHI_HOTPLUGGED      = (1 << 0),  /* could have been hotplugged */
        ATA_EHI_RESUME_LINK     = (1 << 1),  /* resume link (reset modifier) */
        ATA_EHI_NO_AUTOPSY      = (1 << 2),  /* no autopsy */
        ATA_EHI_QUIET           = (1 << 3),  /* be quiet */

        ATA_EHI_DID_SOFTRESET   = (1 << 16), /* already soft-reset this port */
        ATA_EHI_DID_HARDRESET   = (1 << 17), /* already soft-reset this port */
        ATA_EHI_PRINTINFO       = (1 << 18), /* print configuration info */
        ATA_EHI_SETMODE         = (1 << 19), /* configure transfer mode */
        ATA_EHI_POST_SETMODE    = (1 << 20), /* revaildating after setmode */

        ATA_EHI_DID_RESET       = ATA_EHI_DID_SOFTRESET | ATA_EHI_DID_HARDRESET,
        ATA_EHI_RESET_MODIFIER_MASK = ATA_EHI_RESUME_LINK,

        /* max repeat if error condition is still set after ->error_handler */
        ATA_EH_MAX_REPEAT       = 5,

        /* how hard are we gonna try to probe/recover devices */
        ATA_PROBE_MAX_TRIES     = 3,
        ATA_EH_DEV_TRIES        = 3,

        /* Horkage types. May be set by libata or controller on drives
           (some horkage may be drive/controller pair dependant */

        ATA_HORKAGE_DIAGNOSTIC  = (1 << 0),     /* Failed boot diag */
        ATA_HORKAGE_NODMA       = (1 << 1),     /* DMA problems */
        ATA_HORKAGE_NONCQ       = (1 << 2),     /* Don't use NCQ */
        ATA_HORKAGE_MAX_SEC_128 = (1 << 3),     /* Limit max sects to 128 */
        ATA_HORKAGE_DMA_RW_ONLY = (1 << 4),     /* ATAPI DMA for RW only */
};

enum hsm_task_states {
        HSM_ST_IDLE,            /* no command on going */
        HSM_ST_FIRST,           /* (waiting the device to)
                                   write CDB or first data block */
        HSM_ST,                 /* (waiting the device to) transfer data */
        HSM_ST_LAST,            /* (waiting the device to) complete command */
        HSM_ST_ERR,             /* error */
};

enum ata_completion_errors {
        AC_ERR_DEV              = (1 << 0), /* device reported error */
        AC_ERR_HSM              = (1 << 1), /* host state machine violation */
        AC_ERR_TIMEOUT          = (1 << 2), /* timeout */
        AC_ERR_MEDIA            = (1 << 3), /* media error */
        AC_ERR_ATA_BUS          = (1 << 4), /* ATA bus error */
        AC_ERR_HOST_BUS         = (1 << 5), /* host bus error */
        AC_ERR_SYSTEM           = (1 << 6), /* system error */
        AC_ERR_INVALID          = (1 << 7), /* invalid argument */
        AC_ERR_OTHER            = (1 << 8), /* unknown */
        AC_ERR_NODEV_HINT       = (1 << 9), /* polling device detection hint */
};

/* forward declarations */
struct scsi_device;
struct ata_port_operations;
struct ata_port;
struct ata_queued_cmd;

/* typedefs */
typedef void (*ata_qc_cb_t) (struct ata_queued_cmd *qc);
typedef int (*ata_prereset_fn_t)(struct ata_port *ap, unsigned long deadline);
typedef int (*ata_reset_fn_t)(struct ata_port *ap, unsigned int *classes,
                              unsigned long deadline);
typedef void (*ata_postreset_fn_t)(struct ata_port *ap, unsigned int *classes);

struct ata_ioports {
        void __iomem            *cmd_addr;
        void __iomem            *data_addr;
        void __iomem            *error_addr;
        void __iomem            *feature_addr;
        void __iomem            *nsect_addr;
        void __iomem            *lbal_addr;
        void __iomem            *lbam_addr;
        void __iomem            *lbah_addr;
        void __iomem            *device_addr;
        void __iomem            *status_addr;
        void __iomem            *command_addr;
        void __iomem            *altstatus_addr;
        void __iomem            *ctl_addr;
        void __iomem            *bmdma_addr;
        void __iomem            *scr_addr;
};

struct ata_host {
        spinlock_t              lock;
        struct device           *dev;
        unsigned long           irq;
        unsigned long           irq2;
        void __iomem * const    *iomap;
        unsigned int            n_ports;
        void                    *private_data;
        const struct ata_port_operations *ops;
        unsigned long           flags;
        struct ata_port         *simplex_claimed;       /* channel owning the DMA */
        struct ata_port         *ports[0];
};

struct ata_queued_cmd {
        struct ata_port         *ap;
        struct ata_device       *dev;

        struct scsi_cmnd        *scsicmd;
        void                    (*scsidone)(struct scsi_cmnd *);

        struct ata_taskfile     tf;
        u8                      cdb[ATAPI_CDB_LEN];

        unsigned long           flags;          /* ATA_QCFLAG_xxx */
        unsigned int            tag;
        unsigned int            n_elem;
        unsigned int            orig_n_elem;

        int                     dma_dir;

        unsigned int            pad_len;
        unsigned int            sect_size;

        unsigned int            nbytes;
        unsigned int            curbytes;

        unsigned int            cursg;
        unsigned int            cursg_ofs;

        struct scatterlist      sgent;
        struct scatterlist      pad_sgent;
        void                    *buf_virt;

        /* DO NOT iterate over __sg manually, use ata_for_each_sg() */
        struct scatterlist      *__sg;

        unsigned int            err_mask;
        struct ata_taskfile     result_tf;
        ata_qc_cb_t             complete_fn;

        void                    *private_data;
};

struct ata_port_stats {
        unsigned long           unhandled_irq;
        unsigned long           idle_irq;
        unsigned long           rw_reqbuf;
};

struct ata_ering_entry {
        int                     is_io;
        unsigned int            err_mask;
        u64                     timestamp;
};

struct ata_ering {
        int                     cursor;
        struct ata_ering_entry  ring[ATA_ERING_SIZE];
};

struct ata_device {
        struct ata_port         *ap;
        unsigned int            devno;          /* 0 or 1 */
        unsigned long           flags;          /* ATA_DFLAG_xxx */
        struct scsi_device      *sdev;          /* attached SCSI device */
        /* n_sector is used as CLEAR_OFFSET, read comment above CLEAR_OFFSET */
        u64                     n_sectors;      /* size of device, if ATA */
        unsigned int            class;          /* ATA_DEV_xxx */
        u16                     id[ATA_ID_WORDS]; /* IDENTIFY xxx DEVICE data */
        u8                      pio_mode;
        u8                      dma_mode;
        u8                      xfer_mode;
        unsigned int            xfer_shift;     /* ATA_SHIFT_xxx */

        unsigned int            multi_count;    /* sectors count for
                                                   READ/WRITE MULTIPLE */
        unsigned int            max_sectors;    /* per-device max sectors */
        unsigned int            cdb_len;

        /* per-dev xfer mask */
        unsigned int            pio_mask;
        unsigned int            mwdma_mask;
        unsigned int            udma_mask;

        /* for CHS addressing */
        u16                     cylinders;      /* Number of cylinders */
        u16                     heads;          /* Number of heads */
        u16                     sectors;        /* Number of sectors per track */

        /* error history */
        struct ata_ering        ering;
        int                     spdn_cnt;
        unsigned int            horkage;        /* List of broken features */
#ifdef CONFIG_ATA_ACPI
        /* ACPI objects info */
        acpi_handle obj_handle;
#endif
};

/* Offset into struct ata_device.  Fields above it are maintained
 * acress device init.  Fields below are zeroed.
 */
#define ATA_DEVICE_CLEAR_OFFSET         offsetof(struct ata_device, n_sectors)

struct ata_eh_info {
        struct ata_device       *dev;           /* offending device */
        u32                     serror;         /* SError from LLDD */
        unsigned int            err_mask;       /* port-wide err_mask */
        unsigned int            action;         /* ATA_EH_* action mask */
        unsigned int            dev_action[ATA_MAX_DEVICES]; /* dev EH action */
        unsigned int            flags;          /* ATA_EHI_* flags */

        unsigned int            probe_mask;

        char                    desc[ATA_EH_DESC_LEN];
        int                     desc_len;
};

struct ata_eh_context {
        struct ata_eh_info      i;
        int                     tries[ATA_MAX_DEVICES];
        unsigned int            classes[ATA_MAX_DEVICES];
        unsigned int            did_probe_mask;
};

struct ata_port {
        struct Scsi_Host        *scsi_host; /* our co-allocated scsi host */
        const struct ata_port_operations *ops;
        spinlock_t              *lock;
        unsigned long           flags;  /* ATA_FLAG_xxx */
        unsigned int            pflags; /* ATA_PFLAG_xxx */
        unsigned int            print_id; /* user visible unique port ID */
        unsigned int            port_no; /* 0 based port no. inside the host */

        struct ata_prd          *prd;    /* our SG list */
        dma_addr_t              prd_dma; /* and its DMA mapping */

        void                    *pad;   /* array of DMA pad buffers */
        dma_addr_t              pad_dma;

        struct ata_ioports      ioaddr; /* ATA cmd/ctl/dma register blocks */

        u8                      ctl;    /* cache of ATA control register */
        u8                      last_ctl;       /* Cache last written value */
        unsigned int            pio_mask;
        unsigned int            mwdma_mask;
        unsigned int            udma_mask;
        unsigned int            cbl;    /* cable type; ATA_CBL_xxx */
        unsigned int            hw_sata_spd_limit;
        unsigned int            sata_spd_limit; /* SATA PHY speed limit */

        /* record runtime error info, protected by host lock */
        struct ata_eh_info      eh_info;
        /* EH context owned by EH */
        struct ata_eh_context   eh_context;

        struct ata_device       device[ATA_MAX_DEVICES];

        struct ata_queued_cmd   qcmd[ATA_MAX_QUEUE];
        unsigned long           qc_allocated;
        unsigned int            qc_active;

        unsigned int            active_tag;
        u32                     sactive;

        struct ata_port_stats   stats;
        struct ata_host         *host;
        struct device           *dev;

        void                    *port_task_data;
        struct delayed_work     port_task;
        struct delayed_work     hotplug_task;
        struct work_struct      scsi_rescan_task;

        unsigned int            hsm_task_state;

        u32                     msg_enable;
        struct list_head        eh_done_q;
        wait_queue_head_t       eh_wait_q;

        pm_message_t            pm_mesg;
        int                     *pm_result;

        void                    *private_data;

        u8                      sector_buf[ATA_SECT_SIZE]; /* owned by EH */
};

struct ata_port_operations {
        void (*port_disable) (struct ata_port *);

        void (*dev_config) (struct ata_device *);

        void (*set_piomode) (struct ata_port *, struct ata_device *);
        void (*set_dmamode) (struct ata_port *, struct ata_device *);
        unsigned long (*mode_filter) (struct ata_device *, unsigned long);

        void (*tf_load) (struct ata_port *ap, const struct ata_taskfile *tf);
        void (*tf_read) (struct ata_port *ap, struct ata_taskfile *tf);

        void (*exec_command)(struct ata_port *ap, const struct ata_taskfile *tf);
        u8   (*check_status)(struct ata_port *ap);
        u8   (*check_altstatus)(struct ata_port *ap);
        void (*dev_select)(struct ata_port *ap, unsigned int device);

        void (*phy_reset) (struct ata_port *ap); /* obsolete */
        int  (*set_mode) (struct ata_port *ap, struct ata_device **r_failed_dev);

        int (*cable_detect) (struct ata_port *ap);

        int  (*check_atapi_dma) (struct ata_queued_cmd *qc);

        void (*bmdma_setup) (struct ata_queued_cmd *qc);
        void (*bmdma_start) (struct ata_queued_cmd *qc);

        void (*data_xfer) (struct ata_device *, unsigned char *, unsigned int, int);

        void (*qc_prep) (struct ata_queued_cmd *qc);
        unsigned int (*qc_issue) (struct ata_queued_cmd *qc);

        /* Error handlers.  ->error_handler overrides ->eng_timeout and
         * indicates that new-style EH is in place.
         */
        void (*eng_timeout) (struct ata_port *ap); /* obsolete */

        void (*freeze) (struct ata_port *ap);
        void (*thaw) (struct ata_port *ap);
        void (*error_handler) (struct ata_port *ap);
        void (*post_internal_cmd) (struct ata_queued_cmd *qc);

        irq_handler_t irq_handler;
        void (*irq_clear) (struct ata_port *);
        u8 (*irq_on) (struct ata_port *);
        u8 (*irq_ack) (struct ata_port *ap, unsigned int chk_drq);

        u32 (*scr_read) (struct ata_port *ap, unsigned int sc_reg);
        void (*scr_write) (struct ata_port *ap, unsigned int sc_reg,
                           u32 val);

        int (*port_suspend) (struct ata_port *ap, pm_message_t mesg);
        int (*port_resume) (struct ata_port *ap);

        int (*port_start) (struct ata_port *ap);
        void (*port_stop) (struct ata_port *ap);

        void (*host_stop) (struct ata_host *host);

        void (*bmdma_stop) (struct ata_queued_cmd *qc);
        u8   (*bmdma_status) (struct ata_port *ap);
};

struct ata_port_info {
        struct scsi_host_template       *sht;
        unsigned long           flags;
        unsigned long           pio_mask;
        unsigned long           mwdma_mask;
        unsigned long           udma_mask;
        const struct ata_port_operations *port_ops;
        irq_handler_t           irq_handler;
        void                    *private_data;
};

struct ata_timing {
        unsigned short mode;            /* ATA mode */
        unsigned short setup;           /* t1 */
        unsigned short act8b;           /* t2 for 8-bit I/O */
        unsigned short rec8b;           /* t2i for 8-bit I/O */
        unsigned short cyc8b;           /* t0 for 8-bit I/O */
        unsigned short active;          /* t2 or tD */
        unsigned short recover;         /* t2i or tK */
        unsigned short cycle;           /* t0 */
        unsigned short udma;            /* t2CYCTYP/2 */
};

#define FIT(v,vmin,vmax)        max_t(short,min_t(short,v,vmax),vmin)

extern const unsigned long sata_deb_timing_normal[];
extern const unsigned long sata_deb_timing_hotplug[];
extern const unsigned long sata_deb_timing_long[];

extern const struct ata_port_operations ata_dummy_port_ops;
extern const struct ata_port_info ata_dummy_port_info;

static inline const unsigned long *
sata_ehc_deb_timing(struct ata_eh_context *ehc)
{
        if (ehc->i.flags & ATA_EHI_HOTPLUGGED)
                return sata_deb_timing_hotplug;
        else
                return sata_deb_timing_normal;
}

static inline int ata_port_is_dummy(struct ata_port *ap)
{
        return ap->ops == &ata_dummy_port_ops;
}

extern void sata_print_link_status(struct ata_port *ap);
extern void ata_port_probe(struct ata_port *);
extern void __sata_phy_reset(struct ata_port *ap);
extern void sata_phy_reset(struct ata_port *ap);
extern void ata_bus_reset(struct ata_port *ap);
extern int sata_set_spd(struct ata_port *ap);
extern int sata_phy_debounce(struct ata_port *ap, const unsigned long *param,
                             unsigned long deadline);
extern int sata_phy_resume(struct ata_port *ap, const unsigned long *param,
                           unsigned long deadline);
extern int ata_std_prereset(struct ata_port *ap, unsigned long deadline);
extern int ata_std_softreset(struct ata_port *ap, unsigned int *classes,
                             unsigned long deadline);
extern int sata_port_hardreset(struct ata_port *ap, const unsigned long *timing,
                               unsigned long deadline);
extern int sata_std_hardreset(struct ata_port *ap, unsigned int *class,
                              unsigned long deadline);
extern void ata_std_postreset(struct ata_port *ap, unsigned int *classes);
extern void ata_port_disable(struct ata_port *);
extern void ata_std_ports(struct ata_ioports *ioaddr);
#ifdef CONFIG_PCI
extern int ata_pci_init_one (struct pci_dev *pdev,
                             const struct ata_port_info * const * ppi);
extern void ata_pci_remove_one (struct pci_dev *pdev);
#ifdef CONFIG_PM
extern void ata_pci_device_do_suspend(struct pci_dev *pdev, pm_message_t mesg);
extern int __must_check ata_pci_device_do_resume(struct pci_dev *pdev);
extern int ata_pci_device_suspend(struct pci_dev *pdev, pm_message_t mesg);
extern int ata_pci_device_resume(struct pci_dev *pdev);
#endif
extern int ata_pci_clear_simplex(struct pci_dev *pdev);
#endif /* CONFIG_PCI */
extern struct ata_host *ata_host_alloc(struct device *dev, int max_ports);
extern struct ata_host *ata_host_alloc_pinfo(struct device *dev,
                        const struct ata_port_info * const * ppi, int n_ports);
extern int ata_host_start(struct ata_host *host);
extern int ata_host_register(struct ata_host *host,
                             struct scsi_host_template *sht);
extern int ata_host_activate(struct ata_host *host, int irq,
                             irq_handler_t irq_handler, unsigned long irq_flags,
                             struct scsi_host_template *sht);
extern void ata_host_detach(struct ata_host *host);
extern void ata_host_init(struct ata_host *, struct device *,
                          unsigned long, const struct ata_port_operations *);
extern int ata_scsi_detect(struct scsi_host_template *sht);
extern int ata_scsi_ioctl(struct scsi_device *dev, int cmd, void __user *arg);
extern int ata_scsi_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *));
extern void ata_sas_port_destroy(struct ata_port *);
extern struct ata_port *ata_sas_port_alloc(struct ata_host *,
                                           struct ata_port_info *, struct Scsi_Host *);
extern int ata_sas_port_init(struct ata_port *);
extern int ata_sas_port_start(struct ata_port *ap);
extern void ata_sas_port_stop(struct ata_port *ap);
extern int ata_sas_slave_configure(struct scsi_device *, struct ata_port *);
extern int ata_sas_queuecmd(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *),
                            struct ata_port *ap);
extern unsigned int ata_host_intr(struct ata_port *ap, struct ata_queued_cmd *qc);
extern int sata_scr_valid(struct ata_port *ap);
extern int sata_scr_read(struct ata_port *ap, int reg, u32 *val);
extern int sata_scr_write(struct ata_port *ap, int reg, u32 val);
extern int sata_scr_write_flush(struct ata_port *ap, int reg, u32 val);
extern int ata_port_online(struct ata_port *ap);
extern int ata_port_offline(struct ata_port *ap);
#ifdef CONFIG_PM
extern int ata_host_suspend(struct ata_host *host, pm_message_t mesg);
extern void ata_host_resume(struct ata_host *host);
#endif
extern int ata_ratelimit(void);
extern int ata_busy_sleep(struct ata_port *ap,
                          unsigned long timeout_pat, unsigned long timeout);
extern int ata_wait_ready(struct ata_port *ap, unsigned long deadline);
extern void ata_port_queue_task(struct ata_port *ap, work_func_t fn,
                                void *data, unsigned long delay);
extern u32 ata_wait_register(void __iomem *reg, u32 mask, u32 val,
                             unsigned long interval_msec,
                             unsigned long timeout_msec);
extern unsigned int ata_dev_try_classify(struct ata_port *, unsigned int, u8 *);

/*
 * Default driver ops implementations
 */
extern void ata_tf_load(struct ata_port *ap, const struct ata_taskfile *tf);
extern void ata_tf_read(struct ata_port *ap, struct ata_taskfile *tf);
extern void ata_tf_to_fis(const struct ata_taskfile *tf, u8 *fis, u8 pmp);
extern void ata_tf_from_fis(const u8 *fis, struct ata_taskfile *tf);
extern void ata_noop_dev_select (struct ata_port *ap, unsigned int device);
extern void ata_std_dev_select (struct ata_port *ap, unsigned int device);
extern u8 ata_check_status(struct ata_port *ap);
extern u8 ata_altstatus(struct ata_port *ap);
extern void ata_exec_command(struct ata_port *ap, const struct ata_taskfile *tf);
extern int ata_port_start (struct ata_port *ap);
extern irqreturn_t ata_interrupt (int irq, void *dev_instance);
extern void ata_data_xfer(struct ata_device *adev, unsigned char *buf,
                          unsigned int buflen, int write_data);
extern void ata_data_xfer_noirq(struct ata_device *adev, unsigned char *buf,
                                unsigned int buflen, int write_data);
extern void ata_qc_prep(struct ata_queued_cmd *qc);
extern void ata_noop_qc_prep(struct ata_queued_cmd *qc);
extern unsigned int ata_qc_issue_prot(struct ata_queued_cmd *qc);
extern void ata_sg_init_one(struct ata_queued_cmd *qc, void *buf,
                unsigned int buflen);
extern void ata_sg_init(struct ata_queued_cmd *qc, struct scatterlist *sg,
                 unsigned int n_elem);
extern unsigned int ata_dev_classify(const struct ata_taskfile *tf);
extern void ata_dev_disable(struct ata_device *adev);
extern void ata_id_string(const u16 *id, unsigned char *s,
                          unsigned int ofs, unsigned int len);
extern void ata_id_c_string(const u16 *id, unsigned char *s,
                            unsigned int ofs, unsigned int len);
extern void ata_id_to_dma_mode(struct ata_device *dev, u8 unknown);
extern unsigned long ata_device_blacklisted(const struct ata_device *dev);
extern void ata_bmdma_setup (struct ata_queued_cmd *qc);
extern void ata_bmdma_start (struct ata_queued_cmd *qc);
extern void ata_bmdma_stop(struct ata_queued_cmd *qc);
extern u8   ata_bmdma_status(struct ata_port *ap);
extern void ata_bmdma_irq_clear(struct ata_port *ap);
extern void ata_bmdma_freeze(struct ata_port *ap);
extern void ata_bmdma_thaw(struct ata_port *ap);
extern void ata_bmdma_drive_eh(struct ata_port *ap, ata_prereset_fn_t prereset,
                               ata_reset_fn_t softreset,
                               ata_reset_fn_t hardreset,
                               ata_postreset_fn_t postreset);
extern void ata_bmdma_error_handler(struct ata_port *ap);
extern void ata_bmdma_post_internal_cmd(struct ata_queued_cmd *qc);
extern int ata_hsm_move(struct ata_port *ap, struct ata_queued_cmd *qc,
                        u8 status, int in_wq);
extern void ata_qc_complete(struct ata_queued_cmd *qc);
extern int ata_qc_complete_multiple(struct ata_port *ap, u32 qc_active,
                                    void (*finish_qc)(struct ata_queued_cmd *));
extern void ata_scsi_simulate(struct ata_device *dev, struct scsi_cmnd *cmd,
                              void (*done)(struct scsi_cmnd *));
extern int ata_std_bios_param(struct scsi_device *sdev,
                              struct block_device *bdev,
                              sector_t capacity, int geom[]);
extern int ata_scsi_slave_config(struct scsi_device *sdev);
extern void ata_scsi_slave_destroy(struct scsi_device *sdev);
extern int ata_scsi_change_queue_depth(struct scsi_device *sdev,
                                       int queue_depth);
extern struct ata_device *ata_dev_pair(struct ata_device *adev);
extern int ata_do_set_mode(struct ata_port *ap, struct ata_device **r_failed_dev);
extern u8 ata_irq_on(struct ata_port *ap);
extern u8 ata_dummy_irq_on(struct ata_port *ap);
extern u8 ata_irq_ack(struct ata_port *ap, unsigned int chk_drq);
extern u8 ata_dummy_irq_ack(struct ata_port *ap, unsigned int chk_drq);

extern int ata_cable_40wire(struct ata_port *ap);
extern int ata_cable_80wire(struct ata_port *ap);
extern int ata_cable_sata(struct ata_port *ap);
extern int ata_cable_unknown(struct ata_port *ap);

/*
 * Timing helpers
 */

extern unsigned int ata_pio_need_iordy(const struct ata_device *);
extern int ata_timing_compute(struct ata_device *, unsigned short,
                              struct ata_timing *, int, int);
extern void ata_timing_merge(const struct ata_timing *,
                             const struct ata_timing *, struct ata_timing *,
                             unsigned int);

enum {
        ATA_TIMING_SETUP        = (1 << 0),
        ATA_TIMING_ACT8B        = (1 << 1),
        ATA_TIMING_REC8B        = (1 << 2),
        ATA_TIMING_CYC8B        = (1 << 3),
        ATA_TIMING_8BIT         = ATA_TIMING_ACT8B | ATA_TIMING_REC8B |
                                  ATA_TIMING_CYC8B,
        ATA_TIMING_ACTIVE       = (1 << 4),
        ATA_TIMING_RECOVER      = (1 << 5),
        ATA_TIMING_CYCLE        = (1 << 6),
        ATA_TIMING_UDMA         = (1 << 7),
        ATA_TIMING_ALL          = ATA_TIMING_SETUP | ATA_TIMING_ACT8B |
                                  ATA_TIMING_REC8B | ATA_TIMING_CYC8B |
                                  ATA_TIMING_ACTIVE | ATA_TIMING_RECOVER |
                                  ATA_TIMING_CYCLE | ATA_TIMING_UDMA,
};


#ifdef CONFIG_PCI
struct pci_bits {
        unsigned int            reg;    /* PCI config register to read */
        unsigned int            width;  /* 1 (8 bit), 2 (16 bit), 4 (32 bit) */
        unsigned long           mask;
        unsigned long           val;
};

extern int ata_pci_init_native_host(struct ata_host *host);
extern int ata_pci_init_bmdma(struct ata_host *host);
extern int ata_pci_prepare_native_host(struct pci_dev *pdev,
                                const struct ata_port_info * const * ppi,
                                struct ata_host **r_host);
extern int pci_test_config_bits(struct pci_dev *pdev, const struct pci_bits *bits);
extern unsigned long ata_pci_default_filter(struct ata_device *, unsigned long);
#endif /* CONFIG_PCI */

/*
 * EH
 */
extern void ata_eng_timeout(struct ata_port *ap);

extern void ata_port_schedule_eh(struct ata_port *ap);
extern int ata_port_abort(struct ata_port *ap);
extern int ata_port_freeze(struct ata_port *ap);

extern void ata_eh_freeze_port(struct ata_port *ap);
extern void ata_eh_thaw_port(struct ata_port *ap);

extern void ata_eh_qc_complete(struct ata_queued_cmd *qc);
extern void ata_eh_qc_retry(struct ata_queued_cmd *qc);

extern void ata_do_eh(struct ata_port *ap, ata_prereset_fn_t prereset,
                      ata_reset_fn_t softreset, ata_reset_fn_t hardreset,
                      ata_postreset_fn_t postreset);

/*
 * printk helpers
 */
#define ata_port_printk(ap, lv, fmt, args...) \
        printk(lv"ata%u: "fmt, (ap)->print_id , ##args)

#define ata_dev_printk(dev, lv, fmt, args...) \
        printk(lv"ata%u.%02u: "fmt, (dev)->ap->print_id, (dev)->devno , ##args)

/*
 * ata_eh_info helpers
 */
#define ata_ehi_push_desc(ehi, fmt, args...) do { \
        (ehi)->desc_len += scnprintf((ehi)->desc + (ehi)->desc_len, \
                                     ATA_EH_DESC_LEN - (ehi)->desc_len, \
                                     fmt , ##args); \
} while (0)

#define ata_ehi_clear_desc(ehi) do { \
        (ehi)->desc[0] = '\0'; \
        (ehi)->desc_len = 0; \
} while (0)

static inline void __ata_ehi_hotplugged(struct ata_eh_info *ehi)
{
        ehi->flags |= ATA_EHI_HOTPLUGGED | ATA_EHI_RESUME_LINK;
        ehi->action |= ATA_EH_SOFTRESET;
        ehi->probe_mask |= (1 << ATA_MAX_DEVICES) - 1;
}

static inline void ata_ehi_hotplugged(struct ata_eh_info *ehi)
{
        __ata_ehi_hotplugged(ehi);
        ehi->err_mask |= AC_ERR_ATA_BUS;
}

/*
 * qc helpers
 */
static inline int
ata_sg_is_last(struct scatterlist *sg, struct ata_queued_cmd *qc)
{
        if (sg == &qc->pad_sgent)
                return 1;
        if (qc->pad_len)
                return 0;
        if (((sg - qc->__sg) + 1) == qc->n_elem)
                return 1;
        return 0;
}

static inline struct scatterlist *
ata_qc_first_sg(struct ata_queued_cmd *qc)
{
        if (qc->n_elem)
                return qc->__sg;
        if (qc->pad_len)
                return &qc->pad_sgent;
        return NULL;
}

static inline struct scatterlist *
ata_qc_next_sg(struct scatterlist *sg, struct ata_queued_cmd *qc)
{
        if (sg == &qc->pad_sgent)
                return NULL;
        if (++sg - qc->__sg < qc->n_elem)
                return sg;
        if (qc->pad_len)
                return &qc->pad_sgent;
        return NULL;
}

#define ata_for_each_sg(sg, qc) \
        for (sg = ata_qc_first_sg(qc); sg; sg = ata_qc_next_sg(sg, qc))

static inline unsigned int ata_tag_valid(unsigned int tag)
{
        return (tag < ATA_MAX_QUEUE) ? 1 : 0;
}

static inline unsigned int ata_tag_internal(unsigned int tag)
{
        return tag == ATA_MAX_QUEUE - 1;
}

/*
 * device helpers
 */
static inline unsigned int ata_class_enabled(unsigned int class)
{
        return class == ATA_DEV_ATA || class == ATA_DEV_ATAPI;
}

static inline unsigned int ata_class_disabled(unsigned int class)
{
        return class == ATA_DEV_ATA_UNSUP || class == ATA_DEV_ATAPI_UNSUP;
}

static inline unsigned int ata_class_absent(unsigned int class)
{
        return !ata_class_enabled(class) && !ata_class_disabled(class);
}

static inline unsigned int ata_dev_enabled(const struct ata_device *dev)
{
        return ata_class_enabled(dev->class);
}

static inline unsigned int ata_dev_disabled(const struct ata_device *dev)
{
        return ata_class_disabled(dev->class);
}

static inline unsigned int ata_dev_absent(const struct ata_device *dev)
{
        return ata_class_absent(dev->class);
}

/*
 * port helpers
 */
static inline int ata_port_max_devices(const struct ata_port *ap)
{
        if (ap->flags & ATA_FLAG_SLAVE_POSS)
                return 2;
        return 1;
}


static inline u8 ata_chk_status(struct ata_port *ap)
{
        return ap->ops->check_status(ap);
}

/**
 *      ata_ncq_enabled - Test whether NCQ is enabled
 *      @dev: ATA device to test for
 *
 *      LOCKING:
 *      spin_lock_irqsave(host lock)
 *
 *      RETURNS:
 *      1 if NCQ is enabled for @dev, 0 otherwise.
 */
static inline int ata_ncq_enabled(struct ata_device *dev)
{
        return (dev->flags & (ATA_DFLAG_PIO | ATA_DFLAG_NCQ_OFF |
                              ATA_DFLAG_NCQ)) == ATA_DFLAG_NCQ;
}

/**
 *      ata_pause - Flush writes and pause 400 nanoseconds.
 *      @ap: Port to wait for.
 *
 *      LOCKING:
 *      Inherited from caller.
 */

static inline void ata_pause(struct ata_port *ap)
{
        ata_altstatus(ap);
        ndelay(400);
}


/**
 *      ata_busy_wait - Wait for a port status register
 *      @ap: Port to wait for.
 *      @bits: bits that must be clear
 *      @max: number of 10uS waits to perform
 *
 *      Waits up to max*10 microseconds for the selected bits in the port's
 *      status register to be cleared.
 *      Returns final value of status register.
 *
 *      LOCKING:
 *      Inherited from caller.
 */

static inline u8 ata_busy_wait(struct ata_port *ap, unsigned int bits,
                               unsigned int max)
{
        u8 status;

        do {
                udelay(10);
                status = ata_chk_status(ap);
                max--;
        } while (status != 0xff && (status & bits) && (max > 0));

        return status;
}


/**
 *      ata_wait_idle - Wait for a port to be idle.
 *      @ap: Port to wait for.
 *
 *      Waits up to 10ms for port's BUSY and DRQ signals to clear.
 *      Returns final value of status register.
 *
 *      LOCKING:
 *      Inherited from caller.
 */

static inline u8 ata_wait_idle(struct ata_port *ap)
{
        u8 status = ata_busy_wait(ap, ATA_BUSY | ATA_DRQ, 1000);

        if (status != 0xff && (status & (ATA_BUSY | ATA_DRQ))) {
                if (ata_msg_warn(ap))
                        printk(KERN_WARNING "ATA: abnormal status 0x%X on port 0x%p\n",
                                status, ap->ioaddr.status_addr);
        }

        return status;
}

static inline void ata_qc_set_polling(struct ata_queued_cmd *qc)
{
        qc->tf.ctl |= ATA_NIEN;
}

static inline struct ata_queued_cmd *__ata_qc_from_tag(struct ata_port *ap,
                                                       unsigned int tag)
{
        if (likely(ata_tag_valid(tag)))
                return &ap->qcmd[tag];
        return NULL;
}

static inline struct ata_queued_cmd *ata_qc_from_tag(struct ata_port *ap,
                                                     unsigned int tag)
{
        struct ata_queued_cmd *qc = __ata_qc_from_tag(ap, tag);

        if (unlikely(!qc) || !ap->ops->error_handler)
                return qc;

        if ((qc->flags & (ATA_QCFLAG_ACTIVE |
                          ATA_QCFLAG_FAILED)) == ATA_QCFLAG_ACTIVE)
                return qc;

        return NULL;
}

static inline void ata_tf_init(struct ata_device *dev, struct ata_taskfile *tf)
{
        memset(tf, 0, sizeof(*tf));

        tf->ctl = dev->ap->ctl;
        if (dev->devno == 0)
                tf->device = ATA_DEVICE_OBS;
        else
                tf->device = ATA_DEVICE_OBS | ATA_DEV1;
}

static inline void ata_qc_reinit(struct ata_queued_cmd *qc)
{
        qc->dma_dir = DMA_NONE;
        qc->__sg = NULL;
        qc->flags = 0;
        qc->cursg = qc->cursg_ofs = 0;
        qc->nbytes = qc->curbytes = 0;
        qc->n_elem = 0;
        qc->err_mask = 0;
        qc->pad_len = 0;
        qc->sect_size = ATA_SECT_SIZE;

        ata_tf_init(qc->dev, &qc->tf);

        /* init result_tf such that it indicates normal completion */
        qc->result_tf.command = ATA_DRDY;
        qc->result_tf.feature = 0;
}

static inline int ata_try_flush_cache(const struct ata_device *dev)
{
        return ata_id_wcache_enabled(dev->id) ||
               ata_id_has_flush(dev->id) ||
               ata_id_has_flush_ext(dev->id);
}

static inline unsigned int ac_err_mask(u8 status)
{
        if (status & (ATA_BUSY | ATA_DRQ))
                return AC_ERR_HSM;
        if (status & (ATA_ERR | ATA_DF))
                return AC_ERR_DEV;
        return 0;
}

static inline unsigned int __ac_err_mask(u8 status)
{
        unsigned int mask = ac_err_mask(status);
        if (mask == 0)
                return AC_ERR_OTHER;
        return mask;
}

static inline int ata_pad_alloc(struct ata_port *ap, struct device *dev)
{
        ap->pad_dma = 0;
        ap->pad = dmam_alloc_coherent(dev, ATA_DMA_PAD_BUF_SZ,
                                      &ap->pad_dma, GFP_KERNEL);
        return (ap->pad == NULL) ? -ENOMEM : 0;
}

static inline void ata_pad_free(struct ata_port *ap, struct device *dev)
{
        dmam_free_coherent(dev, ATA_DMA_PAD_BUF_SZ, ap->pad, ap->pad_dma);
}

static inline struct ata_port *ata_shost_to_port(struct Scsi_Host *host)
{
        return *(struct ata_port **)&host->hostdata[0];
}

#endif /* __LINUX_LIBATA_H__ */