/* SPDX-License-Identifier: GPL-2.0+ *//* * Driver for USB Mass Storage compliant devices * Protocol Functions Header File * * 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. */ #ifndef _PROTOCOL_H_#define _PROTOCOL_H_ /* Protocol handling routines */extern void usb_stor_pad12_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