    /*
     * usbif.h
     *
     * USB I/O interface for Xen guest OSes.
     *
     * Copyright (C) 2009, FUJITSU LABORATORIES LTD.
     * Author: Noboru Iwamatsu <n_iwamatsu@jp.fujitsu.com>
     *
     * Permission is hereby granted, free of charge, to any person obtaining a copy
     * of this software and associated documentation files (the "Software"), to
     * deal in the Software without restriction, including without limitation the
     * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
     * sell copies of the Software, and to permit persons to whom the Software is
     * furnished to do so, subject to the following conditions:
     *
     * The above copyright notice and this permission notice shall be included in
     * all copies or substantial portions of the Software.
     *
     * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
     * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
     * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
     * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
     * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
     * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
     * DEALINGS IN THE SOFTWARE.
     */

    #ifndef __XEN_PUBLIC_IO_USBIF_H__
    #define __XEN_PUBLIC_IO_USBIF_H__

    #include "ring.h"
    #include "../grant_table.h"

    /*
     * Feature and Parameter Negotiation
     * =================================
     * The two halves of a Xen pvUSB driver utilize nodes within the XenStore to
     * communicate capabilities and to negotiate operating parameters. This
     * section enumerates these nodes which reside in the respective front and
     * backend portions of the XenStore, following the XenBus convention.
     *
     * Any specified default value is in effect if the corresponding XenBus node
     * is not present in the XenStore.
     *
     * XenStore nodes in sections marked "PRIVATE" are solely for use by the
     * driver side whose XenBus tree contains them.
     *
     *****************************************************************************
     *                            Backend XenBus Nodes
     *****************************************************************************
     *
     *------------------ Backend Device Identification (PRIVATE) ------------------
     *
     * num-ports
     *      Values:         unsigned [1...31]
     *
     *      Number of ports for this (virtual) USB host connector.
     *
     * usb-ver
     *      Values:         unsigned [1...2]
     *
     *      USB version of this host connector: 1 = USB 1.1, 2 = USB 2.0.
     *
     * port/[1...31]
     *      Values:         string
     *
     *      Physical USB device connected to the given port, e.g. "3-1.5".
     *
     *****************************************************************************
     *                            Frontend XenBus Nodes
     *****************************************************************************
     *
     *----------------------- Request Transport Parameters -----------------------
     *
     * event-channel
     *      Values:         unsigned
     *
     *      The identifier of the Xen event channel used to signal activity
     *      in the ring buffer.
     *
     * urb-ring-ref
     *      Values:         unsigned
     *
     *      The Xen grant reference granting permission for the backend to map
     *      the sole page in a single page sized ring buffer. This is the ring
     *      buffer for urb requests.
     *
     * conn-ring-ref
     *      Values:         unsigned
     *
     *      The Xen grant reference granting permission for the backend to map
     *      the sole page in a single page sized ring buffer. This is the ring
     *      buffer for connection/disconnection requests.
     *
     * protocol
     *      Values:         string (XEN_IO_PROTO_ABI_*)
     *      Default Value:  XEN_IO_PROTO_ABI_NATIVE
     *
     *      The machine ABI rules governing the format of all ring request and
     *      response structures.
     *
     */

    enum usb_spec_version {
    	USB_VER_UNKNOWN = 0,
    	USB_VER_USB11,
    	USB_VER_USB20,
    	USB_VER_USB30,	/* not supported yet */
    };

    /*
     *  USB pipe in usbif_request
     *
     *  - port number:	bits 0-4
     *				(USB_MAXCHILDREN is 31)
     *
     *  - operation flag:	bit 5
     *				(0 = submit urb,
     *				 1 = unlink urb)
     *
     *  - direction:		bit 7
     *				(0 = Host-to-Device [Out]
     *				 1 = Device-to-Host [In])
     *
     *  - device address:	bits 8-14
     *
     *  - endpoint:		bits 15-18
     *
     *  - pipe type:	bits 30-31
     *				(00 = isochronous, 01 = interrupt,
     *				 10 = control, 11 = bulk)
     */

    #define USBIF_PIPE_PORT_MASK	0x0000001f
    #define USBIF_PIPE_UNLINK	0x00000020
    #define USBIF_PIPE_DIR		0x00000080
    #define USBIF_PIPE_DEV_MASK	0x0000007f
    #define USBIF_PIPE_DEV_SHIFT	8
    #define USBIF_PIPE_EP_MASK	0x0000000f
    #define USBIF_PIPE_EP_SHIFT	15
    #define USBIF_PIPE_TYPE_MASK	0x00000003
    #define USBIF_PIPE_TYPE_SHIFT	30
    #define USBIF_PIPE_TYPE_ISOC	0
    #define USBIF_PIPE_TYPE_INT	1
    #define USBIF_PIPE_TYPE_CTRL	2
    #define USBIF_PIPE_TYPE_BULK	3

    #define usbif_pipeportnum(pipe)			((pipe) & USBIF_PIPE_PORT_MASK)
    #define usbif_setportnum_pipe(pipe, portnum)	((pipe) | (portnum))

    #define usbif_pipeunlink(pipe)			((pipe) & USBIF_PIPE_UNLINK)
    #define usbif_pipesubmit(pipe)			(!usbif_pipeunlink(pipe))
    #define usbif_setunlink_pipe(pipe)		((pipe) | USBIF_PIPE_UNLINK)

    #define usbif_pipein(pipe)			((pipe) & USBIF_PIPE_DIR)
    #define usbif_pipeout(pipe)			(!usbif_pipein(pipe))

    #define usbif_pipedevice(pipe)			\
    		(((pipe) >> USBIF_PIPE_DEV_SHIFT) & USBIF_PIPE_DEV_MASK)

    #define usbif_pipeendpoint(pipe)		\
    		(((pipe) >> USBIF_PIPE_EP_SHIFT) & USBIF_PIPE_EP_MASK)

    #define usbif_pipetype(pipe)			\
    		(((pipe) >> USBIF_PIPE_TYPE_SHIFT) & USBIF_PIPE_TYPE_MASK)
    #define usbif_pipeisoc(pipe)	(usbif_pipetype(pipe) == USBIF_PIPE_TYPE_ISOC)
    #define usbif_pipeint(pipe)	(usbif_pipetype(pipe) == USBIF_PIPE_TYPE_INT)
    #define usbif_pipectrl(pipe)	(usbif_pipetype(pipe) == USBIF_PIPE_TYPE_CTRL)
    #define usbif_pipebulk(pipe)	(usbif_pipetype(pipe) == USBIF_PIPE_TYPE_BULK)

    #define USBIF_MAX_SEGMENTS_PER_REQUEST (16)
    #define USBIF_MAX_PORTNR	31
    #define USBIF_RING_SIZE	4096

    /*
     * RING for transferring urbs.
     */
    struct usbif_request_segment {
    	grant_ref_t gref;
    	uint16_t offset;
    	uint16_t length;
    };

    struct usbif_urb_request {
    	uint16_t id; /* request id */
    	uint16_t nr_buffer_segs; /* number of urb->transfer_buffer segments */

    	/* basic urb parameter */
    	uint32_t pipe;
    	uint16_t transfer_flags;
    #define USBIF_SHORT_NOT_OK	0x0001
    	uint16_t buffer_length;
    	union {
    		uint8_t ctrl[8]; /* setup_packet (Ctrl) */

    		struct {
    			uint16_t interval; /* maximum (1024*8) in usb core */
    			uint16_t start_frame; /* start frame */
    			uint16_t number_of_packets; /* number of ISO packet */
    			uint16_t nr_frame_desc_segs; /* number of iso_frame_desc segments */
    		} isoc;

    		struct {
    			uint16_t interval; /* maximum (1024*8) in usb core */
    			uint16_t pad[3];
    		} intr;

    		struct {
    			uint16_t unlink_id; /* unlink request id */
    			uint16_t pad[3];
    		} unlink;

    	} u;

    	/* urb data segments */
    	struct usbif_request_segment seg[USBIF_MAX_SEGMENTS_PER_REQUEST];
    };
    typedef struct usbif_urb_request usbif_urb_request_t;

    struct usbif_urb_response {
    	uint16_t id; /* request id */
    	uint16_t start_frame;  /* start frame (ISO) */
    	int32_t status; /* status (non-ISO) */
    	int32_t actual_length; /* actual transfer length */
    	int32_t error_count; /* number of ISO errors */
    };
    typedef struct usbif_urb_response usbif_urb_response_t;

    DEFINE_RING_TYPES(usbif_urb, struct usbif_urb_request, struct usbif_urb_response);
    #define USB_URB_RING_SIZE __CONST_RING_SIZE(usbif_urb, USBIF_RING_SIZE)

    /*
     * RING for notifying connect/disconnect events to frontend
     */
    struct usbif_conn_request {
    	uint16_t id;
    };
    typedef struct usbif_conn_request usbif_conn_request_t;

    struct usbif_conn_response {
    	uint16_t id; /* request id */
    	uint8_t portnum; /* port number */
    	uint8_t speed; /* usb_device_speed */
    #define USBIF_SPEED_NONE	0
    #define USBIF_SPEED_LOW		1
    #define USBIF_SPEED_FULL	2
    #define USBIF_SPEED_HIGH	3
    };
    typedef struct usbif_conn_response usbif_conn_response_t;

    DEFINE_RING_TYPES(usbif_conn, struct usbif_conn_request, struct usbif_conn_response);
    #define USB_CONN_RING_SIZE __CONST_RING_SIZE(usbif_conn, USBIF_RING_SIZE)

    #endif /* __XEN_PUBLIC_IO_USBIF_H__ */