1/* SPDX-License-Identifier: GPL-2.0+ */
2/*
3 * Driver for USB Mass Storage compliant devices
4 * Transport 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 _TRANSPORT_H_
25#define _TRANSPORT_H_
26
27#include <linux/blkdev.h>
28
29/*
30 * usb_stor_bulk_transfer_xxx() return codes, in order of severity
31 */
32
33#define USB_STOR_XFER_GOOD	0	/* good transfer                 */
34#define USB_STOR_XFER_SHORT	1	/* transferred less than expected */
35#define USB_STOR_XFER_STALLED	2	/* endpoint stalled              */
36#define USB_STOR_XFER_LONG	3	/* device tried to send too much */
37#define USB_STOR_XFER_ERROR	4	/* transfer died in the middle   */
38
39/*
40 * Transport return codes
41 */
42
43#define USB_STOR_TRANSPORT_GOOD	   0   /* Transport good, command good	   */
44#define USB_STOR_TRANSPORT_FAILED  1   /* Transport good, command failed   */
45#define USB_STOR_TRANSPORT_NO_SENSE 2  /* Command failed, no auto-sense    */
46#define USB_STOR_TRANSPORT_ERROR   3   /* Transport bad (i.e. device dead) */
47
48/*
49 * We used to have USB_STOR_XFER_ABORTED and USB_STOR_TRANSPORT_ABORTED
50 * return codes.  But now the transport and low-level transfer routines
51 * treat an abort as just another error (-ENOENT for a cancelled URB).
52 * It is up to the invoke_transport() function to test for aborts and
53 * distinguish them from genuine communication errors.
54 */
55
56/*
57 * CBI accept device specific command
58 */
59
60#define US_CBI_ADSC		0
61
62extern int usb_stor_CB_transport(struct scsi_cmnd *, struct us_data*);
63extern int usb_stor_CB_reset(struct us_data*);
64
65extern int usb_stor_Bulk_transport(struct scsi_cmnd *, struct us_data*);
66extern int usb_stor_Bulk_max_lun(struct us_data*);
67extern int usb_stor_Bulk_reset(struct us_data*);
68
69extern void usb_stor_invoke_transport(struct scsi_cmnd *, struct us_data*);
70extern void usb_stor_stop_transport(struct us_data*);
71
72extern int usb_stor_control_msg(struct us_data *us, unsigned int pipe,
73		u8 request, u8 requesttype, u16 value, u16 index,
74		void *data, u16 size, int timeout);
75extern int usb_stor_clear_halt(struct us_data *us, unsigned int pipe);
76
77extern int usb_stor_ctrl_transfer(struct us_data *us, unsigned int pipe,
78		u8 request, u8 requesttype, u16 value, u16 index,
79		void *data, u16 size);
80extern int usb_stor_bulk_transfer_buf(struct us_data *us, unsigned int pipe,
81		void *buf, unsigned int length, unsigned int *act_len);
82extern int usb_stor_bulk_transfer_sg(struct us_data *us, unsigned int pipe,
83		void *buf, unsigned int length, int use_sg, int *residual);
84extern int usb_stor_bulk_srb(struct us_data* us, unsigned int pipe,
85		struct scsi_cmnd* srb);
86
87extern int usb_stor_port_reset(struct us_data *us);
88#endif
89