source: mainline/uspace/drv/bus/usb/xhci/isoch.h

/*
 * Copyright (c) 2018 Ondrej Hlavaty
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup drvusbxhci
 * @{
 */
/** @file
 * @brief Data structures and functions related to isochronous transfers.
 */

#ifndef XHCI_ISOCH_H
#define XHCI_ISOCH_H

#include <usb/dma_buffer.h>

#include "trb_ring.h"

#include "transfers.h"

typedef struct xhci_endpoint xhci_endpoint_t;

typedef enum {
        ISOCH_EMPTY,    /* Unused yet */
        ISOCH_FILLED,   /* The data buffer is valid */
        ISOCH_FED,      /* The data buffer is in possession of xHC */
        ISOCH_COMPLETE, /* The error code is valid */
} xhci_isoch_transfer_state_t;

typedef struct {
        /** Buffer with data */
        dma_buffer_t data;
        /** Used buffer size */
        size_t size;

        /** Current state */
        xhci_isoch_transfer_state_t state;

        /** Microframe to which to schedule */
        uint64_t mfindex;

        /** Physical address of enqueued TRB */
        uintptr_t interrupt_trb_phys;

        /** Result of the transfer. Valid only if status == ISOCH_COMPLETE. */
        errno_t error;
} xhci_isoch_transfer_t;

typedef struct {
        /** Protects common buffers. */
        fibril_mutex_t guard;

        /** Signals filled buffer. */
        fibril_condvar_t avail;

        /** Defers handing buffers to the HC. */
        fibril_timer_t *feeding_timer;

        /** Resets endpoint if there is no traffic. */
        fibril_timer_t *reset_timer;

        /**
         * The maximum size of an isochronous transfer
         * and therefore the size of buffers
         */
        size_t max_size;

        /** The microframe at which the last TRB was scheduled. */
        uint64_t last_mf;

        /** The number of transfer buffers allocated */
        size_t buffer_count;

        /** Isochronous scheduled transfers with respective buffers */
        xhci_isoch_transfer_t *transfers;

        /**
         * Out: Next buffer that will be handed to HW.
         * In:  Invalid. Hidden inside HC.
         */
        size_t hw_enqueue;

        /**
         * Out: Next buffer that will be used for writing.
         * In:  Next buffer that will be enqueued to be written by the HC
         */
        size_t enqueue;

        /**
         * Out: First buffer that will be checked for completion
         * In:  Next buffer to be read from, when valid.
         */
        size_t dequeue;
} xhci_isoch_t;

typedef struct usb_endpoint_descriptors usb_endpoint_descriptors_t;

extern void isoch_init(xhci_endpoint_t *, const usb_endpoint_descriptors_t *);
extern void isoch_fini(xhci_endpoint_t *);
extern errno_t isoch_alloc_transfers(xhci_endpoint_t *);

extern errno_t isoch_schedule_out(xhci_transfer_t *);
extern errno_t isoch_schedule_in(xhci_transfer_t *);
extern void isoch_handle_transfer_event(xhci_hc_t *, xhci_endpoint_t *,
    xhci_trb_t *);

#endif

/**
 * @}
 */