1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Driver for USB Mass Storage compliant devices 4 * Protocol Functions Header File 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 /* Protocol handling routines */ 45 extern void usb_stor_pad12_command(struct scsi_cmnd*, struct us_data*); 46 extern void usb_stor_ufi_command(struct scsi_cmnd*, struct us_data*); 47 extern void usb_stor_transparent_scsi_command(struct scsi_cmnd*, 48 struct us_data*); 49 50 /* struct scsi_cmnd transfer buffer access utilities */ 51 enum xfer_buf_dir {TO_XFER_BUF, FROM_XFER_BUF}; 52 53 extern unsigned int usb_stor_access_xfer_buf(unsigned char *buffer, 54 unsigned int buflen, struct scsi_cmnd *srb, struct scatterlist **, 55 unsigned int *offset, enum xfer_buf_dir dir); 56 57 extern void usb_stor_set_xfer_buf(unsigned char *buffer, 58 unsigned int buflen, struct scsi_cmnd *srb); 59 #endif 60