ref: 899ec4d0b568a6d51a85e5344733a2189a7ba1ec
dir: /sys/src/cmd/nusb/disk/ums.h/
/* * mass storage transport protocols and subclasses, * from usb mass storage class specification overview rev 1.2 */ typedef struct Umsc Umsc; typedef struct Ums Ums; typedef struct Cbw Cbw; /* command block wrapper */ typedef struct Csw Csw; /* command status wrapper */ typedef struct Part Part; enum { Protocbi = 0, /* control/bulk/interrupt; mainly floppies */ Protocb = 1, /* " with no interrupt; mainly floppies */ Protobulk = 0x50, /* bulk only */ Subrbc = 1, /* reduced blk cmds */ Subatapi = 2, /* cd/dvd using sff-8020i or mmc-2 cmd blks */ Subqic = 3, /* QIC-157 tapes */ Subufi = 4, /* floppy */ Sub8070 = 5, /* removable media, atapi-like */ Subscsi = 6, /* scsi transparent cmd set */ Subisd200 = 7, /* ISD200 ATA */ Subdev = 0xff, /* use device's value */ Umsreset = 0xFF, Getmaxlun = 0xFE, // Maxlun = 256, Maxlun = 32, CMreset = 1, Pcmd = 0, Pdata, Pstatus, CbwLen = 31, CbwDataIn = 0x80, CbwDataOut = 0x00, CswLen = 13, CswOk = 0, CswFailed = 1, CswPhaseErr = 2, Maxparts = 16, }; /* * corresponds to a lun. * these are ~600+Maxiosize bytes each; ScsiReq is not tiny. */ struct Part { int id; int inuse; int vers; ulong mode; char *name; vlong offset; /* in lbsize units */ vlong length; /* in lbsize units */ }; struct Umsc { ScsiReq; char name[40]; uvlong blocks; vlong capacity; /* from setup */ char *bufp; long off; /* offset within a block */ long nb; /* byte count */ QLock; /* partitions */ Part part[Maxparts]; uchar rawcmd[16]; uchar phase; char *inq; Ums *ums; char buf[Maxiosize]; }; struct Ums { Dev *epin; Dev *epout; Umsc *lun; uchar maxlun; int seq; int nerrs; int wrongresidues; }; /* * USB transparent SCSI devices */ struct Cbw { char signature[4]; /* "USBC" */ long tag; long datalen; uchar flags; uchar lun; uchar len; char command[16]; }; struct Csw { char signature[4]; /* "USBS" */ long tag; long dataresidue; uchar status; };