linux/drivers/usb/storage/protocol.h
Jens Axboe 1f6f31a03e USB storage: sg chaining support
[PATCH] USB storage: sg chaining support

Modify usb_stor_access_xfer_buf() to take a pointer to an sg
entry pointer, so we can keep track of that instead of passing
around an integer index (which we can't use when dealing with
multiple scatterlist arrays).

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-16 11:20:59 +02:00

60 lines
2.5 KiB
C

/* Driver for USB Mass Storage compliant devices
* Protocol Functions Header File
*
* $Id: protocol.h,v 1.4 2001/02/13 07:10:03 mdharm Exp $
*
* Current development and maintenance by:
* (c) 1999, 2000 Matthew Dharm (mdharm-usb@one-eyed-alien.net)
*
* This driver is based on the 'USB Mass Storage Class' document. This
* describes in detail the protocol used to communicate with such
* devices. Clearly, the designers had SCSI and ATAPI commands in
* mind when they created this document. The commands are all very
* similar to commands in the SCSI-II and ATAPI specifications.
*
* It is important to note that in a number of cases this class
* exhibits class-specific exemptions from the USB specification.
* Notably the usage of NAK, STALL and ACK differs from the norm, in
* that they are used to communicate wait, failed and OK on commands.
*
* Also, for certain devices, the interrupt endpoint is used to convey
* status of a command.
*
* Please see http://www.one-eyed-alien.net/~mdharm/linux-usb for more
* information about this driver.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2, or (at your option) any
* later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#ifndef _PROTOCOL_H_
#define _PROTOCOL_H_
/* Protocol handling routines */
extern void usb_stor_ATAPI_command(struct scsi_cmnd*, struct us_data*);
extern void usb_stor_qic157_command(struct scsi_cmnd*, struct us_data*);
extern void usb_stor_ufi_command(struct scsi_cmnd*, struct us_data*);
extern void usb_stor_transparent_scsi_command(struct scsi_cmnd*,
struct us_data*);
/* struct scsi_cmnd transfer buffer access utilities */
enum xfer_buf_dir {TO_XFER_BUF, FROM_XFER_BUF};
extern unsigned int usb_stor_access_xfer_buf(unsigned char *buffer,
unsigned int buflen, struct scsi_cmnd *srb, struct scatterlist **,
unsigned int *offset, enum xfer_buf_dir dir);
extern void usb_stor_set_xfer_buf(unsigned char *buffer,
unsigned int buflen, struct scsi_cmnd *srb);
#endif