usb.h

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/* Driver for USB Mass Storage compliant devices
 * Main Header File
 *
 * Current development and maintenance by:
 *   (c) 1999-2002 Matthew Dharm ([email protected])
 *
 * Initial work by:
 *   (c) 1999 Michael Gee ([email protected])
 *
 * This driver is based on the 'USB Mass Storage Class' document. This
 * describes in detail the protocol used to communicate with such
 * devices.  Clearly, the designers had SCSI and ATAPI commands in
 * mind when they created this document.  The commands are all very
 * similar to commands in the SCSI-II and ATAPI specifications.
 *
 * It is important to note that in a number of cases this class
 * exhibits class-specific exemptions from the USB specification.
 * Notably the usage of NAK, STALL and ACK differs from the norm, in
 * that they are used to communicate wait, failed and OK on commands.
 *
 * Also, for certain devices, the interrupt endpoint is used to convey
 * status of a command.
 *
 * Please see http://www.one-eyed-alien.net/~mdharm/linux-usb for more
 * information about this driver.
 *
 * 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; if not, write to the Free Software Foundation, Inc.,
 * 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#ifndef _USB_H_
#define _USB_H_

#include <linux/usb.h>
#include <linux/usb_usual.h>
#include <linux/blkdev.h>
#include <linux/completion.h>
#include <linux/mutex.h>
#include <linux/workqueue.h>
#include <scsi/scsi_host.h>

struct us_data;
struct scsi_cmnd;

/*
 * Unusual device list definitions 
 */

struct us_unusual_dev {
    const char* vendorName;
    const char* productName;
    __u8  useProtocol;
    __u8  useTransport;
    int (*initFunction)(struct us_data *);
};


/* Dynamic bitflag definitions (us->dflags): used in set_bit() etc. */
#define US_FLIDX_URB_ACTIVE 0   /* current_urb is in use    */
#define US_FLIDX_SG_ACTIVE  1   /* current_sg is in use     */
#define US_FLIDX_ABORTING   2   /* abort is in progress     */
#define US_FLIDX_DISCONNECTING  3   /* disconnect in progress   */
#define US_FLIDX_RESETTING  4   /* device reset in progress */
#define US_FLIDX_TIMED_OUT  5   /* SCSI midlayer timed out  */
#define US_FLIDX_SCAN_PENDING   6   /* scanning not yet done    */
#define US_FLIDX_REDO_READ10    7   /* redo READ(10) command    */
#define US_FLIDX_READ10_WORKED  8   /* previous READ(10) succeeded */

#define USB_STOR_STRING_LEN 32

/*
 * We provide a DMA-mapped I/O buffer for use with small USB transfers.
 * It turns out that CB[I] needs a 12-byte buffer and Bulk-only needs a
 * 31-byte buffer.  But Freecom needs a 64-byte buffer, so that's the
 * size we'll allocate.
 */

#define US_IOBUF_SIZE       64  /* Size of the DMA-mapped I/O buffer */
#define US_SENSE_SIZE       18  /* Size of the autosense data buffer */

typedef int (*trans_cmnd)(struct scsi_cmnd *, struct us_data*);
typedef int (*trans_reset)(struct us_data*);
typedef void (*proto_cmnd)(struct scsi_cmnd*, struct us_data*);
typedef void (*extra_data_destructor)(void *);  /* extra data destructor */
typedef void (*pm_hook)(struct us_data *, int); /* power management hook */

#define US_SUSPEND  0
#define US_RESUME   1

/* we allocate one of these for every device that we remember */
struct us_data {
    /* The device we're working with
     * It's important to note:
     *    (o) you must hold dev_mutex to change pusb_dev
     */
    struct mutex        dev_mutex;   /* protect pusb_dev */
    struct usb_device   *pusb_dev;   /* this usb_device */
    struct usb_interface    *pusb_intf;  /* this interface */
    struct us_unusual_dev   *unusual_dev;    /* device-filter entry     */
    unsigned long       fflags;      /* fixed flags from filter */
    unsigned long       dflags;      /* dynamic atomic bitflags */
    unsigned int        send_bulk_pipe;  /* cached pipe values */
    unsigned int        recv_bulk_pipe;
    unsigned int        send_ctrl_pipe;
    unsigned int        recv_ctrl_pipe;
    unsigned int        recv_intr_pipe;

    /* information about the device */
    char            *transport_name;
    char            *protocol_name;
    __le32          bcs_signature;
    u8          subclass;
    u8          protocol;
    u8          max_lun;

    u8          ifnum;       /* interface number   */
    u8          ep_bInterval;    /* interrupt interval */ 

    /* function pointers for this device */
    trans_cmnd      transport;   /* transport function     */
    trans_reset     transport_reset; /* transport device reset */
    proto_cmnd      proto_handler;   /* protocol handler       */

    /* SCSI interfaces */
    struct scsi_cmnd    *srb;        /* current srb     */
    unsigned int        tag;         /* current dCBWTag */
    char            scsi_name[32];   /* scsi_host name  */

    /* control and bulk communications data */
    struct urb      *current_urb;    /* USB requests     */
    struct usb_ctrlrequest  *cr;         /* control requests     */
    struct usb_sg_request   current_sg;  /* scatter-gather req.  */
    unsigned char       *iobuf;      /* I/O buffer       */
    dma_addr_t      iobuf_dma;   /* buffer DMA addresses */
    struct task_struct  *ctl_thread;     /* the control thread   */

    /* mutual exclusion and synchronization structures */
    struct completion   cmnd_ready;  /* to sleep thread on      */
    struct completion   notify;      /* thread begin/end        */
    wait_queue_head_t   delay_wait;  /* wait during reset       */
    struct delayed_work scan_dwork;  /* for async scanning      */

    /* subdriver information */
    void            *extra;      /* Any extra data          */
    extra_data_destructor   extra_destructor;/* extra data destructor   */
#ifdef CONFIG_PM
    pm_hook         suspend_resume_hook;
#endif

    /* hacks for READ CAPACITY bug handling */
    int         use_last_sector_hacks;
    int         last_sector_retries;
};

/* Convert between us_data and the corresponding Scsi_Host */
static inline struct Scsi_Host *us_to_host(struct us_data *us) {
    return container_of((void *) us, struct Scsi_Host, hostdata);
}
static inline struct us_data *host_to_us(struct Scsi_Host *host) {
    return (struct us_data *) host->hostdata;
}

/* Function to fill an inquiry response. See usb.c for details */
extern void fill_inquiry_response(struct us_data *us,
    unsigned char *data, unsigned int data_len);

/* The scsi_lock() and scsi_unlock() macros protect the sm_state and the
 * single queue element srb for write access */
#define scsi_unlock(host)   spin_unlock_irq(host->host_lock)
#define scsi_lock(host)     spin_lock_irq(host->host_lock)

/* General routines provided by the usb-storage standard core */
#ifdef CONFIG_PM
extern int usb_stor_suspend(struct usb_interface *iface, pm_message_t message);
extern int usb_stor_resume(struct usb_interface *iface);
extern int usb_stor_reset_resume(struct usb_interface *iface);
#else
#define usb_stor_suspend    NULL
#define usb_stor_resume     NULL
#define usb_stor_reset_resume   NULL
#endif

extern int usb_stor_pre_reset(struct usb_interface *iface);
extern int usb_stor_post_reset(struct usb_interface *iface);

extern int usb_stor_probe1(struct us_data **pus,
        struct usb_interface *intf,
        const struct usb_device_id *id,
        struct us_unusual_dev *unusual_dev);
extern int usb_stor_probe2(struct us_data *us);
extern void usb_stor_disconnect(struct usb_interface *intf);

#endif