1 /* Driver for USB Mass Storage compliant devices 2 * Transport Functions Header File 3 * 4 * $Id: transport.h,v 1.18 2002/04/21 02:57:59 mdharm Exp $ 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 _TRANSPORT_H_ 42 #define _TRANSPORT_H_ 43 44 #include <linux/blkdev.h> 45 46 /* 47 * Bulk only data structures 48 */ 49 50 /* command block wrapper */ 51 struct bulk_cb_wrap { 52 __le32 Signature; /* contains 'USBC' */ 53 __u32 Tag; /* unique per command id */ 54 __le32 DataTransferLength; /* size of data */ 55 __u8 Flags; /* direction in bit 0 */ 56 __u8 Lun; /* LUN normally 0 */ 57 __u8 Length; /* of of the CDB */ 58 __u8 CDB[16]; /* max command */ 59 }; 60 61 #define US_BULK_CB_WRAP_LEN 31 62 #define US_BULK_CB_SIGN 0x43425355 /*spells out USBC */ 63 #define US_BULK_FLAG_IN 1 64 #define US_BULK_FLAG_OUT 0 65 66 /* command status wrapper */ 67 struct bulk_cs_wrap { 68 __le32 Signature; /* should = 'USBS' */ 69 __u32 Tag; /* same as original command */ 70 __le32 Residue; /* amount not transferred */ 71 __u8 Status; /* see below */ 72 __u8 Filler[18]; 73 }; 74 75 #define US_BULK_CS_WRAP_LEN 13 76 #define US_BULK_CS_SIGN 0x53425355 /* spells out 'USBS' */ 77 #define US_BULK_STAT_OK 0 78 #define US_BULK_STAT_FAIL 1 79 #define US_BULK_STAT_PHASE 2 80 81 /* bulk-only class specific requests */ 82 #define US_BULK_RESET_REQUEST 0xff 83 #define US_BULK_GET_MAX_LUN 0xfe 84 85 /* 86 * usb_stor_bulk_transfer_xxx() return codes, in order of severity 87 */ 88 89 #define USB_STOR_XFER_GOOD 0 /* good transfer */ 90 #define USB_STOR_XFER_SHORT 1 /* transferred less than expected */ 91 #define USB_STOR_XFER_STALLED 2 /* endpoint stalled */ 92 #define USB_STOR_XFER_LONG 3 /* device tried to send too much */ 93 #define USB_STOR_XFER_ERROR 4 /* transfer died in the middle */ 94 95 /* 96 * Transport return codes 97 */ 98 99 #define USB_STOR_TRANSPORT_GOOD 0 /* Transport good, command good */ 100 #define USB_STOR_TRANSPORT_FAILED 1 /* Transport good, command failed */ 101 #define USB_STOR_TRANSPORT_NO_SENSE 2 /* Command failed, no auto-sense */ 102 #define USB_STOR_TRANSPORT_ERROR 3 /* Transport bad (i.e. device dead) */ 103 104 /* 105 * We used to have USB_STOR_XFER_ABORTED and USB_STOR_TRANSPORT_ABORTED 106 * return codes. But now the transport and low-level transfer routines 107 * treat an abort as just another error (-ENOENT for a cancelled URB). 108 * It is up to the invoke_transport() function to test for aborts and 109 * distinguish them from genuine communication errors. 110 */ 111 112 /* 113 * CBI accept device specific command 114 */ 115 116 #define US_CBI_ADSC 0 117 118 extern int usb_stor_CBI_transport(struct scsi_cmnd *, struct us_data*); 119 120 extern int usb_stor_CB_transport(struct scsi_cmnd *, struct us_data*); 121 extern int usb_stor_CB_reset(struct us_data*); 122 123 extern int usb_stor_Bulk_transport(struct scsi_cmnd *, struct us_data*); 124 extern int usb_stor_Bulk_max_lun(struct us_data*); 125 extern int usb_stor_Bulk_reset(struct us_data*); 126 127 extern void usb_stor_invoke_transport(struct scsi_cmnd *, struct us_data*); 128 extern void usb_stor_stop_transport(struct us_data*); 129 130 extern int usb_stor_control_msg(struct us_data *us, unsigned int pipe, 131 u8 request, u8 requesttype, u16 value, u16 index, 132 void *data, u16 size, int timeout); 133 extern int usb_stor_clear_halt(struct us_data *us, unsigned int pipe); 134 135 extern int usb_stor_ctrl_transfer(struct us_data *us, unsigned int pipe, 136 u8 request, u8 requesttype, u16 value, u16 index, 137 void *data, u16 size); 138 extern int usb_stor_bulk_transfer_buf(struct us_data *us, unsigned int pipe, 139 void *buf, unsigned int length, unsigned int *act_len); 140 extern int usb_stor_bulk_transfer_sg(struct us_data *us, unsigned int pipe, 141 void *buf, unsigned int length, int use_sg, int *residual); 142 143 extern int usb_stor_port_reset(struct us_data *us); 144 #endif 145