/* SPDX-License-Identifier: GPL-2.0 */
#ifndef USB_STORAGE_COMMON_H
#define USB_STORAGE_COMMON_H

#include <linux/device.h>
#include <linux/usb/storage.h>
#include <scsi/scsi.h>
#include <linux/unaligned.h>

#ifndef DEBUG
#undef VERBOSE_DEBUG
#undef DUMP_MSGS
#endif /* !DEBUG */

#ifdef VERBOSE_DEBUG
#define VLDBG   LDBG
#else
#define VLDBG(lun, fmt, args...) do { } while (0)
#endif /* VERBOSE_DEBUG */

#define _LMSG(func, lun, fmt, args...)                                  \
        do {                                                            \
                if ((lun)->name_pfx && *(lun)->name_pfx)                \
                        func("%s/%s: " fmt, *(lun)->name_pfx,           \
                                 (lun)->name, ## args);                 \
                else                                                    \
                        func("%s: " fmt, (lun)->name, ## args);         \
        } while (0)

#define LDBG(lun, fmt, args...)         _LMSG(pr_debug, lun, fmt, ## args)
#define LERROR(lun, fmt, args...)       _LMSG(pr_err, lun, fmt, ## args)
#define LWARN(lun, fmt, args...)        _LMSG(pr_warn, lun, fmt, ## args)
#define LINFO(lun, fmt, args...)        _LMSG(pr_info, lun, fmt, ## args)


#ifdef DUMP_MSGS

#  define dump_msg(fsg, /* const char * */ label,                       \
                   /* const u8 * */ buf, /* unsigned */ length)         \
do {                                                                    \
        if (length < 512) {                                             \
                DBG(fsg, "%s, length %u:\n", label, length);            \
                print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET,      \
                               16, 1, buf, length, 0);                  \
        }                                                               \
} while (0)

#  define dump_cdb(fsg) do { } while (0)

#else

#  define dump_msg(fsg, /* const char * */ label, \
                   /* const u8 * */ buf, /* unsigned */ length) do { } while (0)

#  ifdef VERBOSE_DEBUG

#    define dump_cdb(fsg)                                               \
        print_hex_dump(KERN_DEBUG, "SCSI CDB: ", DUMP_PREFIX_NONE,      \
                       16, 1, (fsg)->cmnd, (fsg)->cmnd_size, 0)         \

#  else

#    define dump_cdb(fsg) do { } while (0)

#  endif /* VERBOSE_DEBUG */

#endif /* DUMP_MSGS */

/* Length of a SCSI Command Data Block */
#define MAX_COMMAND_SIZE        16

/* SCSI Sense Key/Additional Sense Code/ASC Qualifier values */
#define SS_NO_SENSE                             0
#define SS_COMMUNICATION_FAILURE                0x040800
#define SS_INVALID_COMMAND                      0x052000
#define SS_INVALID_FIELD_IN_CDB                 0x052400
#define SS_LOGICAL_BLOCK_ADDRESS_OUT_OF_RANGE   0x052100
#define SS_LOGICAL_UNIT_NOT_SUPPORTED           0x052500
#define SS_MEDIUM_NOT_PRESENT                   0x023a00
#define SS_MEDIUM_REMOVAL_PREVENTED             0x055302
#define SS_NOT_READY_TO_READY_TRANSITION        0x062800
#define SS_RESET_OCCURRED                       0x062900
#define SS_SAVING_PARAMETERS_NOT_SUPPORTED      0x053900
#define SS_UNRECOVERED_READ_ERROR               0x031100
#define SS_WRITE_ERROR                          0x030c02
#define SS_WRITE_PROTECTED                      0x072700

#define SK(x)           ((u8) ((x) >> 16))      /* Sense Key byte, etc. */
#define ASC(x)          ((u8) ((x) >> 8))
#define ASCQ(x)         ((u8) (x))

/*
 * Vendor (8 chars), product (16 chars), release (4 hexadecimal digits) and NUL
 * byte
 */
#define INQUIRY_STRING_LEN ((size_t) (8 + 16 + 4 + 1))

struct fsg_lun {
        struct file     *filp;
        loff_t          file_length;
        loff_t          num_sectors;

        unsigned int    initially_ro:1;
        unsigned int    ro:1;
        unsigned int    removable:1;
        unsigned int    cdrom:1;
        unsigned int    prevent_medium_removal:1;
        unsigned int    registered:1;
        unsigned int    info_valid:1;
        unsigned int    nofua:1;

        u32             sense_data;
        u32             sense_data_info;
        u32             unit_attention_data;

        unsigned int    blkbits; /* Bits of logical block size
                                                       of bound block device */
        unsigned int    blksize; /* logical block size of bound block device */
        struct device   dev;
        const char      *name;          /* "lun.name" */
        const char      **name_pfx;     /* "function.name" */
        char            inquiry_string[INQUIRY_STRING_LEN];
};

static inline bool fsg_lun_is_open(struct fsg_lun *curlun)
{
        return curlun->filp != NULL;
}

/* Default size of buffer length. */
#define FSG_BUFLEN      ((u32)16384)

/* Maximal number of LUNs supported in mass storage function */
#define FSG_MAX_LUNS    (US_BULK_MAX_LUN_LIMIT + 1)

enum fsg_buffer_state {
        BUF_STATE_SENDING = -2,
        BUF_STATE_RECEIVING,
        BUF_STATE_EMPTY = 0,
        BUF_STATE_FULL
};

struct fsg_buffhd {
        void                            *buf;
        enum fsg_buffer_state           state;
        struct fsg_buffhd               *next;

        /*
         * The NetChip 2280 is faster, and handles some protocol faults
         * better, if we don't submit any short bulk-out read requests.
         * So we will record the intended request length here.
         */
        unsigned int                    bulk_out_intended_length;

        struct usb_request              *inreq;
        struct usb_request              *outreq;
};

enum fsg_state {
        FSG_STATE_NORMAL,
        FSG_STATE_ABORT_BULK_OUT,
        FSG_STATE_PROTOCOL_RESET,
        FSG_STATE_CONFIG_CHANGE,
        FSG_STATE_EXIT,
        FSG_STATE_TERMINATED
};

enum data_direction {
        DATA_DIR_UNKNOWN = 0,
        DATA_DIR_FROM_HOST,
        DATA_DIR_TO_HOST,
        DATA_DIR_NONE
};

static inline struct fsg_lun *fsg_lun_from_dev(struct device *dev)
{
        return container_of(dev, struct fsg_lun, dev);
}

enum {
        FSG_STRING_INTERFACE
};

extern struct usb_interface_descriptor fsg_intf_desc;

extern struct usb_endpoint_descriptor fsg_fs_bulk_in_desc;
extern struct usb_endpoint_descriptor fsg_fs_bulk_out_desc;
extern struct usb_descriptor_header *fsg_fs_function[];

extern struct usb_endpoint_descriptor fsg_hs_bulk_in_desc;
extern struct usb_endpoint_descriptor fsg_hs_bulk_out_desc;
extern struct usb_descriptor_header *fsg_hs_function[];

extern struct usb_endpoint_descriptor fsg_ss_bulk_in_desc;
extern struct usb_ss_ep_comp_descriptor fsg_ss_bulk_in_comp_desc;
extern struct usb_endpoint_descriptor fsg_ss_bulk_out_desc;
extern struct usb_ss_ep_comp_descriptor fsg_ss_bulk_out_comp_desc;
extern struct usb_descriptor_header *fsg_ss_function[];

void fsg_lun_close(struct fsg_lun *curlun);
int fsg_lun_open(struct fsg_lun *curlun, const char *filename);
int fsg_lun_fsync_sub(struct fsg_lun *curlun);
void store_cdrom_address(u8 *dest, int msf, u32 addr);
ssize_t fsg_show_ro(struct fsg_lun *curlun, char *buf);
ssize_t fsg_show_nofua(struct fsg_lun *curlun, char *buf);
ssize_t fsg_show_file(struct fsg_lun *curlun, struct rw_semaphore *filesem,
                      char *buf);
ssize_t fsg_show_inquiry_string(struct fsg_lun *curlun, char *buf);
ssize_t fsg_show_cdrom(struct fsg_lun *curlun, char *buf);
ssize_t fsg_show_removable(struct fsg_lun *curlun, char *buf);
ssize_t fsg_store_ro(struct fsg_lun *curlun, struct rw_semaphore *filesem,
                     const char *buf, size_t count);
ssize_t fsg_store_nofua(struct fsg_lun *curlun, const char *buf, size_t count);
ssize_t fsg_store_file(struct fsg_lun *curlun, struct rw_semaphore *filesem,
                       const char *buf, size_t count);
ssize_t fsg_store_cdrom(struct fsg_lun *curlun, struct rw_semaphore *filesem,
                        const char *buf, size_t count);
ssize_t fsg_store_removable(struct fsg_lun *curlun, const char *buf,
                            size_t count);
ssize_t fsg_store_inquiry_string(struct fsg_lun *curlun, const char *buf,
                                 size_t count);
ssize_t fsg_store_forced_eject(struct fsg_lun *curlun, struct rw_semaphore *filesem,
                               const char *buf, size_t count);

#endif /* USB_STORAGE_COMMON_H */