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
24 #ifndef _PROTOCOL_H_
25 #define _PROTOCOL_H_
26
27 /* Protocol handling routines */
28 extern void usb_stor_pad12_command(struct scsi_cmnd*, struct us_data*);
29 extern void usb_stor_ufi_command(struct scsi_cmnd*, struct us_data*);
30 extern void usb_stor_transparent_scsi_command(struct scsi_cmnd*,
31 struct us_data*);
32
33 /* struct scsi_cmnd transfer buffer access utilities */
34 enum xfer_buf_dir {TO_XFER_BUF, FROM_XFER_BUF};
35
36 extern unsigned int usb_stor_access_xfer_buf(unsigned char *buffer,
37 unsigned int buflen, struct scsi_cmnd *srb, struct scatterlist **,
38 unsigned int *offset, enum xfer_buf_dir dir);
39
40 extern void usb_stor_set_xfer_buf(unsigned char *buffer,
41 unsigned int buflen, struct scsi_cmnd *srb);
42 #endif