/*      $NetBSD: firmload.c,v 1.19 2014/03/25 16:19:13 christos Exp $   */

/*
 * Copyright 2016 Hans Rosenfeld <rosenfeld@grumpf.hope-2000.org>
 */

/*
 * Copyright (c) 2005, 2006 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Jason R. Thorpe.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``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 FOUNDATION OR CONTRIBUTORS
 * 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.
 */

/*
 * The firmload API provides an interface for device drivers to access
 * firmware images that must be loaded onto their devices.
 */

#include <sys/param.h>
#include <sys/fcntl.h>
#include <sys/systm.h>
#include <sys/vnode.h>
#include <sys/lwp.h>
#include <sys/file.h>
#include <sys/cmn_err.h>
#include <sys/modctl.h>
#include <sys/kobj.h>
#include <sys/kobj_impl.h>

#include <sys/firmload.h>

struct firmware_handle {
        struct _buf     *fh_buf;
        off_t            fh_size;
};

static firmware_handle_t
firmware_handle_alloc(void)
{
        return (kmem_alloc(sizeof (struct firmware_handle), KM_SLEEP));
}

static void
firmware_handle_free(firmware_handle_t fh)
{
        kmem_free(fh, sizeof (struct firmware_handle));
}

/*
 * firmware_open:
 *
 *      Open a firmware image and return its handle.
 */
int
firmware_open(const char *drvname, const char *imgname, firmware_handle_t *fhp)
{
        char *path;
        firmware_handle_t fh;
        int error;

        if (drvname == NULL || imgname == NULL || fhp == NULL)
                return (EINVAL);

        path = kmem_asprintf("firmware/%s/%s", drvname, imgname);
        fh = firmware_handle_alloc();

        fh->fh_buf = kobj_open_path(path, 1, 0);
        strfree(path);

        if (fh->fh_buf == (struct _buf *)-1) {
                firmware_handle_free(fh);
                return (ENOENT);
        }

        error = kobj_get_filesize(fh->fh_buf, (uint64_t *)&fh->fh_size);
        if (error != 0) {
                kobj_close_file(fh->fh_buf);
                firmware_handle_free(fh);
                return (error);
        }

        *fhp = fh;
        return (0);
}

/*
 * firmware_close:
 *
 *      Close a firmware image.
 */
int
firmware_close(firmware_handle_t fh)
{
        if (fh != NULL) {
                kobj_close_file(fh->fh_buf);
                firmware_handle_free(fh);
        }
        return (0);
}

/*
 * firmware_get_size:
 *
 *      Return the total size of a firmware image.
 */
off_t
firmware_get_size(firmware_handle_t fh)
{
        ASSERT(fh != NULL);
        return (fh->fh_size);
}

/*
 * firmware_read:
 *
 *      Read data from a firmware image at the specified offset into
 *      the provided buffer.
 */
int
firmware_read(firmware_handle_t fh, off_t offset, void *buf, size_t len)
{
        ASSERT(fh != NULL);
        if (kobj_read_file(fh->fh_buf, buf, len, offset) == -1)
                return (-1);

        return (0);
}