drivers/usb/storage/transport.h

   1 /*
   2  * Driver for USB Mass Storage compliant devices
   3  * Transport Functions Header File
   4  *
   5  * Current development and maintenance by:
   6  *   (c) 1999, 2000 Matthew Dharm (mdharm-usb@one-eyed-alien.net)
   7  *
   8  * This driver is based on the 'USB Mass Storage Class' document. This
   9  * describes in detail the protocol used to communicate with such
  10  * devices.  Clearly, the designers had SCSI and ATAPI commands in
  11  * mind when they created this document.  The commands are all very
  12  * similar to commands in the SCSI-II and ATAPI specifications.
  13  *
  14  * It is important to note that in a number of cases this class
  15  * exhibits class-specific exemptions from the USB specification.
  16  * Notably the usage of NAK, STALL and ACK differs from the norm, in
  17  * that they are used to communicate wait, failed and OK on commands.
  18  *
  19  * Also, for certain devices, the interrupt endpoint is used to convey
  20  * status of a command.
  21  *
  22  * Please see http://www.one-eyed-alien.net/~mdharm/linux-usb for more
  23  * information about this driver.
  24  *
  25  * This program is free software; you can redistribute it and/or modify it
  26  * under the terms of the GNU General Public License as published by the
  27  * Free Software Foundation; either version 2, or (at your option) any
  28  * later version.
  29  *
  30  * This program is distributed in the hope that it will be useful, but
  31  * WITHOUT ANY WARRANTY; without even the implied warranty of
  32  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  33  * General Public License for more details.
  34  *
  35  * You should have received a copy of the GNU General Public License along
  36  * with this program; if not, write to the Free Software Foundation, Inc.,
  37  * 675 Mass Ave, Cambridge, MA 02139, USA.
  38  */
  39
  40 #ifndef _TRANSPORT_H_
  41 #define _TRANSPORT_H_
  42
  43 #include <linux/blkdev.h>
  44
  45 /*
  46  * usb_stor_bulk_transfer_xxx() return codes, in order of severity
  47  */
  48
  49 #define USB_STOR_XFER_GOOD      0       /* good transfer                 */
  50 #define USB_STOR_XFER_SHORT     1       /* transferred less than expected */
  51 #define USB_STOR_XFER_STALLED   2       /* endpoint stalled              */
  52 #define USB_STOR_XFER_LONG      3       /* device tried to send too much */
  53 #define USB_STOR_XFER_ERROR     4       /* transfer died in the middle   */
  54
  55 /*
  56  * Transport return codes
  57  */
  58
  59 #define USB_STOR_TRANSPORT_GOOD    0   /* Transport good, command good     */
  60 #define USB_STOR_TRANSPORT_FAILED  1   /* Transport good, command failed   */
  61 #define USB_STOR_TRANSPORT_NO_SENSE 2  /* Command failed, no auto-sense    */
  62 #define USB_STOR_TRANSPORT_ERROR   3   /* Transport bad (i.e. device dead) */
  63
  64 /*
  65  * We used to have USB_STOR_XFER_ABORTED and USB_STOR_TRANSPORT_ABORTED
  66  * return codes.  But now the transport and low-level transfer routines
  67  * treat an abort as just another error (-ENOENT for a cancelled URB).
  68  * It is up to the invoke_transport() function to test for aborts and
  69  * distinguish them from genuine communication errors.
  70  */
  71
  72 /*
  73  * CBI accept device specific command
  74  */
  75
  76 #define US_CBI_ADSC             0
  77
  78 extern int usb_stor_CB_transport(struct scsi_cmnd *, struct us_data*);
  79 extern int usb_stor_CB_reset(struct us_data*);
  80
  81 extern int usb_stor_Bulk_transport(struct scsi_cmnd *, struct us_data*);
  82 extern int usb_stor_Bulk_max_lun(struct us_data*);
  83 extern int usb_stor_Bulk_reset(struct us_data*);
  84
  85 extern void usb_stor_invoke_transport(struct scsi_cmnd *, struct us_data*);
  86 extern void usb_stor_stop_transport(struct us_data*);
  87
  88 extern int usb_stor_control_msg(struct us_data *us, unsigned int pipe,
  89                 u8 request, u8 requesttype, u16 value, u16 index,
  90                 void *data, u16 size, int timeout);
  91 extern int usb_stor_clear_halt(struct us_data *us, unsigned int pipe);
  92
  93 extern int usb_stor_ctrl_transfer(struct us_data *us, unsigned int pipe,
  94                 u8 request, u8 requesttype, u16 value, u16 index,
  95                 void *data, u16 size);
  96 extern int usb_stor_bulk_transfer_buf(struct us_data *us, unsigned int pipe,
  97                 void *buf, unsigned int length, unsigned int *act_len);
  98 extern int usb_stor_bulk_transfer_sg(struct us_data *us, unsigned int pipe,
  99                 void *buf, unsigned int length, int use_sg, int *residual);
 100 extern int usb_stor_bulk_srb(struct us_data* us, unsigned int pipe,
 101                 struct scsi_cmnd* srb);
 102
 103 extern int usb_stor_port_reset(struct us_data *us);
 104 #endif