/* SPDX-License-Identifier: GPL-2.0+ */
/*
 * Driver for USB Mass Storage compliant devices
 * Main Header File
 *
 * Current development and maintenance by:
 *   (c) 1999-2002 Matthew Dharm (mdharm-usb@one-eyed-alien.net)
 *
 * Initial work by:
 *   (c) 1999 Michael Gee (michael@linuxspecific.com)
 *
 * 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.
 */

#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 */
        const struct us_unusual_dev   *unusual_dev;
                                                /* device-filter entry     */
        u64                     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,
                const struct us_unusual_dev *unusual_dev,
                const struct scsi_host_template *sht);
extern int usb_stor_probe2(struct us_data *us);
extern void usb_stor_disconnect(struct usb_interface *intf);

extern void usb_stor_adjust_quirks(struct usb_device *dev,
                u64 *fflags);

#define module_usb_stor_driver(__driver, __sht, __name) \
static int __init __driver##_init(void) \
{ \
        usb_stor_host_template_init(&(__sht), __name, THIS_MODULE); \
        return usb_register(&(__driver)); \
} \
module_init(__driver##_init); \
static void __exit __driver##_exit(void) \
{ \
        usb_deregister(&(__driver)); \
} \
module_exit(__driver##_exit)

#endif