drivers/usb/storage/protocol.h

   1 /* Driver for USB Mass Storage compliant devices
   2  * Protocol Functions Header File
   3  *
   4  * $Id: protocol.h,v 1.4 2001/02/13 07:10:03 mdharm Exp $
   5  *
   6  * Current development and maintenance by:
   7  *   (c) 1999, 2000 Matthew Dharm (mdharm-usb@one-eyed-alien.net)
   8  *
   9  * This driver is based on the 'USB Mass Storage Class' document. This
  10  * describes in detail the protocol used to communicate with such
  11  * devices.  Clearly, the designers had SCSI and ATAPI commands in
  12  * mind when they created this document.  The commands are all very
  13  * similar to commands in the SCSI-II and ATAPI specifications.
  14  *
  15  * It is important to note that in a number of cases this class
  16  * exhibits class-specific exemptions from the USB specification.
  17  * Notably the usage of NAK, STALL and ACK differs from the norm, in
  18  * that they are used to communicate wait, failed and OK on commands.
  19  *
  20  * Also, for certain devices, the interrupt endpoint is used to convey
  21  * status of a command.
  22  *
  23  * Please see http://www.one-eyed-alien.net/~mdharm/linux-usb for more
  24  * information about this driver.
  25  *
  26  * This program is free software; you can redistribute it and/or modify it
  27  * under the terms of the GNU General Public License as published by the
  28  * Free Software Foundation; either version 2, or (at your option) any
  29  * later version.
  30  *
  31  * This program is distributed in the hope that it will be useful, but
  32  * WITHOUT ANY WARRANTY; without even the implied warranty of
  33  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  34  * General Public License for more details.
  35  *
  36  * You should have received a copy of the GNU General Public License along
  37  * with this program; if not, write to the Free Software Foundation, Inc.,
  38  * 675 Mass Ave, Cambridge, MA 02139, USA.
  39  */
  40
  41 #ifndef _PROTOCOL_H_
  42 #define _PROTOCOL_H_
  43
  44 /* Sub Classes */
  45
  46 #define US_SC_RBC       0x01            /* Typically, flash devices */
  47 #define US_SC_8020      0x02            /* CD-ROM */
  48 #define US_SC_QIC       0x03            /* QIC-157 Tapes */
  49 #define US_SC_UFI       0x04            /* Floppy */
  50 #define US_SC_8070      0x05            /* Removable media */
  51 #define US_SC_SCSI      0x06            /* Transparent */
  52 #define US_SC_ISD200    0x07            /* ISD200 ATA */
  53 #define US_SC_MIN       US_SC_RBC
  54 #define US_SC_MAX       US_SC_ISD200
  55
  56 #define US_SC_DEVICE    0xff            /* Use device's value */
  57
  58 /* Protocol handling routines */
  59 extern void usb_stor_ATAPI_command(struct scsi_cmnd*, struct us_data*);
  60 extern void usb_stor_qic157_command(struct scsi_cmnd*, struct us_data*);
  61 extern void usb_stor_ufi_command(struct scsi_cmnd*, struct us_data*);
  62 extern void usb_stor_transparent_scsi_command(struct scsi_cmnd*,
  63                 struct us_data*);
  64
  65 /* struct scsi_cmnd transfer buffer access utilities */
  66 enum xfer_buf_dir       {TO_XFER_BUF, FROM_XFER_BUF};
  67
  68 extern unsigned int usb_stor_access_xfer_buf(unsigned char *buffer,
  69         unsigned int buflen, struct scsi_cmnd *srb, unsigned int *index,
  70         unsigned int *offset, enum xfer_buf_dir dir);
  71
  72 extern void usb_stor_set_xfer_buf(unsigned char *buffer,
  73         unsigned int buflen, struct scsi_cmnd *srb);
  74 #endif