1 /* Driver for USB Mass Storage compliant devices 2 * Transport Functions Header File 3 * 4 * Current development and maintenance by: 5 * (c) 1999, 2000 Matthew Dharm (mdharm-usb@one-eyed-alien.net) 6 * 7 * This driver is based on the 'USB Mass Storage Class' document. This 8 * describes in detail the protocol used to communicate with such 9 * devices. Clearly, the designers had SCSI and ATAPI commands in 10 * mind when they created this document. The commands are all very 11 * similar to commands in the SCSI-II and ATAPI specifications. 12 * 13 * It is important to note that in a number of cases this class 14 * exhibits class-specific exemptions from the USB specification. 15 * Notably the usage of NAK, STALL and ACK differs from the norm, in 16 * that they are used to communicate wait, failed and OK on commands. 17 * 18 * Also, for certain devices, the interrupt endpoint is used to convey 19 * status of a command. 20 * 21 * Please see http://www.one-eyed-alien.net/~mdharm/linux-usb for more 22 * information about this driver. 23 * 24 * This program is free software; you can redistribute it and/or modify it 25 * under the terms of the GNU General Public License as published by the 26 * Free Software Foundation; either version 2, or (at your option) any 27 * later version. 28 * 29 * This program is distributed in the hope that it will be useful, but 30 * WITHOUT ANY WARRANTY; without even the implied warranty of 31 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 32 * General Public License for more details. 33 * 34 * You should have received a copy of the GNU General Public License along 35 * with this program; if not, write to the Free Software Foundation, Inc., 36 * 675 Mass Ave, Cambridge, MA 02139, USA. 37 */ 38 39 #ifndef _TRANSPORT_H_ 40 #define _TRANSPORT_H_ 41 42 #include <linux/blkdev.h> 43 44 /* 45 * Bulk only data structures 46 */ 47 48 /* command block wrapper */ 49 struct bulk_cb_wrap { 50 __le32 Signature; /* contains 'USBC' */ 51 __u32 Tag; /* unique per command id */ 52 __le32 DataTransferLength; /* size of data */ 53 __u8 Flags; /* direction in bit 0 */ 54 __u8 Lun; /* LUN normally 0 */ 55 __u8 Length; /* of of the CDB */ 56 __u8 CDB[16]; /* max command */ 57 }; 58 59 #define US_BULK_CB_WRAP_LEN 31 60 #define US_BULK_CB_SIGN 0x43425355 /*spells out USBC */ 61 #define US_BULK_FLAG_IN 1 62 #define US_BULK_FLAG_OUT 0 63 64 /* command status wrapper */ 65 struct bulk_cs_wrap { 66 __le32 Signature; /* should = 'USBS' */ 67 __u32 Tag; /* same as original command */ 68 __le32 Residue; /* amount not transferred */ 69 __u8 Status; /* see below */ 70 __u8 Filler[18]; 71 }; 72 73 #define US_BULK_CS_WRAP_LEN 13 74 #define US_BULK_CS_SIGN 0x53425355 /* spells out 'USBS' */ 75 #define US_BULK_STAT_OK 0 76 #define US_BULK_STAT_FAIL 1 77 #define US_BULK_STAT_PHASE 2 78 79 /* bulk-only class specific requests */ 80 #define US_BULK_RESET_REQUEST 0xff 81 #define US_BULK_GET_MAX_LUN 0xfe 82 83 /* 84 * usb_stor_bulk_transfer_xxx() return codes, in order of severity 85 */ 86 87 #define USB_STOR_XFER_GOOD 0 /* good transfer */ 88 #define USB_STOR_XFER_SHORT 1 /* transferred less than expected */ 89 #define USB_STOR_XFER_STALLED 2 /* endpoint stalled */ 90 #define USB_STOR_XFER_LONG 3 /* device tried to send too much */ 91 #define USB_STOR_XFER_ERROR 4 /* transfer died in the middle */ 92 93 /* 94 * Transport return codes 95 */ 96 97 #define USB_STOR_TRANSPORT_GOOD 0 /* Transport good, command good */ 98 #define USB_STOR_TRANSPORT_FAILED 1 /* Transport good, command failed */ 99 #define USB_STOR_TRANSPORT_NO_SENSE 2 /* Command failed, no auto-sense */ 100 #define USB_STOR_TRANSPORT_ERROR 3 /* Transport bad (i.e. device dead) */ 101 102 /* 103 * We used to have USB_STOR_XFER_ABORTED and USB_STOR_TRANSPORT_ABORTED 104 * return codes. But now the transport and low-level transfer routines 105 * treat an abort as just another error (-ENOENT for a cancelled URB). 106 * It is up to the invoke_transport() function to test for aborts and 107 * distinguish them from genuine communication errors. 108 */ 109 110 /* 111 * CBI accept device specific command 112 */ 113 114 #define US_CBI_ADSC 0 115 116 extern int usb_stor_CBI_transport(struct scsi_cmnd *, struct us_data*); 117 118 extern int usb_stor_CB_transport(struct scsi_cmnd *, struct us_data*); 119 extern int usb_stor_CB_reset(struct us_data*); 120 121 extern int usb_stor_Bulk_transport(struct scsi_cmnd *, struct us_data*); 122 extern int usb_stor_Bulk_max_lun(struct us_data*); 123 extern int usb_stor_Bulk_reset(struct us_data*); 124 125 extern void usb_stor_invoke_transport(struct scsi_cmnd *, struct us_data*); 126 extern void usb_stor_stop_transport(struct us_data*); 127 128 extern int usb_stor_control_msg(struct us_data *us, unsigned int pipe, 129 u8 request, u8 requesttype, u16 value, u16 index, 130 void *data, u16 size, int timeout); 131 extern int usb_stor_clear_halt(struct us_data *us, unsigned int pipe); 132 133 extern int usb_stor_ctrl_transfer(struct us_data *us, unsigned int pipe, 134 u8 request, u8 requesttype, u16 value, u16 index, 135 void *data, u16 size); 136 extern int usb_stor_bulk_transfer_buf(struct us_data *us, unsigned int pipe, 137 void *buf, unsigned int length, unsigned int *act_len); 138 extern int usb_stor_bulk_transfer_sg(struct us_data *us, unsigned int pipe, 139 void *buf, unsigned int length, int use_sg, int *residual); 140 extern int usb_stor_bulk_srb(struct us_data* us, unsigned int pipe, 141 struct scsi_cmnd* srb); 142 143 extern int usb_stor_port_reset(struct us_data *us); 144 #endif 145