// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * rionet - Ethernet driver over RapidIO messaging services
 *
 * Copyright 2005 MontaVista Software, Inc.
 * Matt Porter <mporter@kernel.crashing.org>
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/dma-mapping.h>
#include <linux/delay.h>
#include <linux/rio.h>
#include <linux/rio_drv.h>
#include <linux/slab.h>
#include <linux/rio_ids.h>

#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
#include <linux/crc32.h>
#include <linux/ethtool.h>
#include <linux/reboot.h>

#define DRV_NAME        "rionet"
#define DRV_VERSION     "0.3"
#define DRV_AUTHOR      "Matt Porter <mporter@kernel.crashing.org>"
#define DRV_DESC        "Ethernet over RapidIO"

MODULE_AUTHOR(DRV_AUTHOR);
MODULE_DESCRIPTION(DRV_DESC);
MODULE_LICENSE("GPL");

#define RIONET_DEFAULT_MSGLEVEL \
                        (NETIF_MSG_DRV          | \
                         NETIF_MSG_LINK         | \
                         NETIF_MSG_RX_ERR       | \
                         NETIF_MSG_TX_ERR)

#define RIONET_DOORBELL_JOIN    0x1000
#define RIONET_DOORBELL_LEAVE   0x1001

#define RIONET_MAILBOX          0

#define RIONET_TX_RING_SIZE     CONFIG_RIONET_TX_SIZE
#define RIONET_RX_RING_SIZE     CONFIG_RIONET_RX_SIZE
#define RIONET_MAX_NETS         8
#define RIONET_MSG_SIZE         RIO_MAX_MSG_SIZE
#define RIONET_MAX_MTU          (RIONET_MSG_SIZE - ETH_HLEN)

struct rionet_private {
        struct rio_mport *mport;
        struct sk_buff *rx_skb[RIONET_RX_RING_SIZE];
        struct sk_buff *tx_skb[RIONET_TX_RING_SIZE];
        int rx_slot;
        int tx_slot;
        int tx_cnt;
        int ack_slot;
        spinlock_t lock;
        spinlock_t tx_lock;
        u32 msg_enable;
        bool open;
};

struct rionet_peer {
        struct list_head node;
        struct rio_dev *rdev;
        struct resource *res;
};

struct rionet_net {
        struct net_device *ndev;
        struct list_head peers;
        spinlock_t lock;        /* net info access lock */
        struct rio_dev **active;
        int nact;       /* number of active peers */
};

static struct rionet_net nets[RIONET_MAX_NETS];

#define is_rionet_capable(src_ops, dst_ops)                     \
                        ((src_ops & RIO_SRC_OPS_DATA_MSG) &&    \
                         (dst_ops & RIO_DST_OPS_DATA_MSG) &&    \
                         (src_ops & RIO_SRC_OPS_DOORBELL) &&    \
                         (dst_ops & RIO_DST_OPS_DOORBELL))
#define dev_rionet_capable(dev) \
        is_rionet_capable(dev->src_ops, dev->dst_ops)

#define RIONET_MAC_MATCH(x)     (!memcmp((x), "\00\01\00\01", 4))
#define RIONET_GET_DESTID(x)    ((*((u8 *)x + 4) << 8) | *((u8 *)x + 5))

static int rionet_rx_clean(struct net_device *ndev)
{
        int i;
        int error = 0;
        struct rionet_private *rnet = netdev_priv(ndev);
        void *data;

        i = rnet->rx_slot;

        do {
                if (!rnet->rx_skb[i])
                        continue;

                if (!(data = rio_get_inb_message(rnet->mport, RIONET_MAILBOX)))
                        break;

                rnet->rx_skb[i]->data = data;
                skb_put(rnet->rx_skb[i], RIO_MAX_MSG_SIZE);
                rnet->rx_skb[i]->protocol =
                    eth_type_trans(rnet->rx_skb[i], ndev);
                error = __netif_rx(rnet->rx_skb[i]);

                if (error == NET_RX_DROP) {
                        ndev->stats.rx_dropped++;
                } else {
                        ndev->stats.rx_packets++;
                        ndev->stats.rx_bytes += RIO_MAX_MSG_SIZE;
                }

        } while ((i = (i + 1) % RIONET_RX_RING_SIZE) != rnet->rx_slot);

        return i;
}

static void rionet_rx_fill(struct net_device *ndev, int end)
{
        int i;
        struct rionet_private *rnet = netdev_priv(ndev);

        i = rnet->rx_slot;
        do {
                rnet->rx_skb[i] = dev_alloc_skb(RIO_MAX_MSG_SIZE);

                if (!rnet->rx_skb[i])
                        break;

                rio_add_inb_buffer(rnet->mport, RIONET_MAILBOX,
                                   rnet->rx_skb[i]->data);
        } while ((i = (i + 1) % RIONET_RX_RING_SIZE) != end);

        rnet->rx_slot = i;
}

static int rionet_queue_tx_msg(struct sk_buff *skb, struct net_device *ndev,
                               struct rio_dev *rdev)
{
        struct rionet_private *rnet = netdev_priv(ndev);

        rio_add_outb_message(rnet->mport, rdev, 0, skb->data, skb->len);
        rnet->tx_skb[rnet->tx_slot] = skb;

        ndev->stats.tx_packets++;
        ndev->stats.tx_bytes += skb->len;

        if (++rnet->tx_cnt == RIONET_TX_RING_SIZE)
                netif_stop_queue(ndev);

        ++rnet->tx_slot;
        rnet->tx_slot &= (RIONET_TX_RING_SIZE - 1);

        if (netif_msg_tx_queued(rnet))
                printk(KERN_INFO "%s: queued skb len %8.8x\n", DRV_NAME,
                       skb->len);

        return 0;
}

static netdev_tx_t rionet_start_xmit(struct sk_buff *skb,
                                     struct net_device *ndev)
{
        int i;
        struct rionet_private *rnet = netdev_priv(ndev);
        struct ethhdr *eth = (struct ethhdr *)skb->data;
        u16 destid;
        unsigned long flags;
        int add_num = 1;

        spin_lock_irqsave(&rnet->tx_lock, flags);

        if (is_multicast_ether_addr(eth->h_dest))
                add_num = nets[rnet->mport->id].nact;

        if ((rnet->tx_cnt + add_num) > RIONET_TX_RING_SIZE) {
                netif_stop_queue(ndev);
                spin_unlock_irqrestore(&rnet->tx_lock, flags);
                printk(KERN_ERR "%s: BUG! Tx Ring full when queue awake!\n",
                       ndev->name);
                return NETDEV_TX_BUSY;
        }

        if (is_multicast_ether_addr(eth->h_dest)) {
                int count = 0;

                for (i = 0; i < RIO_MAX_ROUTE_ENTRIES(rnet->mport->sys_size);
                                i++)
                        if (nets[rnet->mport->id].active[i]) {
                                rionet_queue_tx_msg(skb, ndev,
                                        nets[rnet->mport->id].active[i]);
                                if (count)
                                        refcount_inc(&skb->users);
                                count++;
                        }
        } else if (RIONET_MAC_MATCH(eth->h_dest)) {
                destid = RIONET_GET_DESTID(eth->h_dest);
                if (nets[rnet->mport->id].active[destid])
                        rionet_queue_tx_msg(skb, ndev,
                                        nets[rnet->mport->id].active[destid]);
                else {
                        /*
                         * If the target device was removed from the list of
                         * active peers but we still have TX packets targeting
                         * it just report sending a packet to the target
                         * (without actual packet transfer).
                         */
                        ndev->stats.tx_packets++;
                        ndev->stats.tx_bytes += skb->len;
                        dev_kfree_skb_any(skb);
                }
        }

        spin_unlock_irqrestore(&rnet->tx_lock, flags);

        return NETDEV_TX_OK;
}

static void rionet_dbell_event(struct rio_mport *mport, void *dev_id, u16 sid, u16 tid,
                               u16 info)
{
        struct net_device *ndev = dev_id;
        struct rionet_private *rnet = netdev_priv(ndev);
        struct rionet_peer *peer;
        unsigned char netid = rnet->mport->id;

        if (netif_msg_intr(rnet))
                printk(KERN_INFO "%s: doorbell sid %4.4x tid %4.4x info %4.4x",
                       DRV_NAME, sid, tid, info);
        if (info == RIONET_DOORBELL_JOIN) {
                if (!nets[netid].active[sid]) {
                        spin_lock(&nets[netid].lock);
                        list_for_each_entry(peer, &nets[netid].peers, node) {
                                if (peer->rdev->destid == sid) {
                                        nets[netid].active[sid] = peer->rdev;
                                        nets[netid].nact++;
                                }
                        }
                        spin_unlock(&nets[netid].lock);

                        rio_mport_send_doorbell(mport, sid,
                                                RIONET_DOORBELL_JOIN);
                }
        } else if (info == RIONET_DOORBELL_LEAVE) {
                spin_lock(&nets[netid].lock);
                if (nets[netid].active[sid]) {
                        nets[netid].active[sid] = NULL;
                        nets[netid].nact--;
                }
                spin_unlock(&nets[netid].lock);
        } else {
                if (netif_msg_intr(rnet))
                        printk(KERN_WARNING "%s: unhandled doorbell\n",
                               DRV_NAME);
        }
}

static void rionet_inb_msg_event(struct rio_mport *mport, void *dev_id, int mbox, int slot)
{
        int n;
        struct net_device *ndev = dev_id;
        struct rionet_private *rnet = netdev_priv(ndev);

        if (netif_msg_intr(rnet))
                printk(KERN_INFO "%s: inbound message event, mbox %d slot %d\n",
                       DRV_NAME, mbox, slot);

        spin_lock(&rnet->lock);
        if ((n = rionet_rx_clean(ndev)) != rnet->rx_slot)
                rionet_rx_fill(ndev, n);
        spin_unlock(&rnet->lock);
}

static void rionet_outb_msg_event(struct rio_mport *mport, void *dev_id, int mbox, int slot)
{
        struct net_device *ndev = dev_id;
        struct rionet_private *rnet = netdev_priv(ndev);

        spin_lock(&rnet->tx_lock);

        if (netif_msg_intr(rnet))
                printk(KERN_INFO
                       "%s: outbound message event, mbox %d slot %d\n",
                       DRV_NAME, mbox, slot);

        while (rnet->tx_cnt && (rnet->ack_slot != slot)) {
                /* dma unmap single */
                dev_kfree_skb_irq(rnet->tx_skb[rnet->ack_slot]);
                rnet->tx_skb[rnet->ack_slot] = NULL;
                ++rnet->ack_slot;
                rnet->ack_slot &= (RIONET_TX_RING_SIZE - 1);
                rnet->tx_cnt--;
        }

        if (rnet->tx_cnt < RIONET_TX_RING_SIZE)
                netif_wake_queue(ndev);

        spin_unlock(&rnet->tx_lock);
}

static int rionet_open(struct net_device *ndev)
{
        int i, rc = 0;
        struct rionet_peer *peer;
        struct rionet_private *rnet = netdev_priv(ndev);
        unsigned char netid = rnet->mport->id;
        unsigned long flags;

        if (netif_msg_ifup(rnet))
                printk(KERN_INFO "%s: open\n", DRV_NAME);

        if ((rc = rio_request_inb_dbell(rnet->mport,
                                        (void *)ndev,
                                        RIONET_DOORBELL_JOIN,
                                        RIONET_DOORBELL_LEAVE,
                                        rionet_dbell_event)) < 0)
                goto out;

        if ((rc = rio_request_inb_mbox(rnet->mport,
                                       (void *)ndev,
                                       RIONET_MAILBOX,
                                       RIONET_RX_RING_SIZE,
                                       rionet_inb_msg_event)) < 0)
                goto out;

        if ((rc = rio_request_outb_mbox(rnet->mport,
                                        (void *)ndev,
                                        RIONET_MAILBOX,
                                        RIONET_TX_RING_SIZE,
                                        rionet_outb_msg_event)) < 0)
                goto out;

        /* Initialize inbound message ring */
        for (i = 0; i < RIONET_RX_RING_SIZE; i++)
                rnet->rx_skb[i] = NULL;
        rnet->rx_slot = 0;
        rionet_rx_fill(ndev, 0);

        rnet->tx_slot = 0;
        rnet->tx_cnt = 0;
        rnet->ack_slot = 0;

        netif_carrier_on(ndev);
        netif_start_queue(ndev);

        spin_lock_irqsave(&nets[netid].lock, flags);
        list_for_each_entry(peer, &nets[netid].peers, node) {
                /* Send a join message */
                rio_send_doorbell(peer->rdev, RIONET_DOORBELL_JOIN);
        }
        spin_unlock_irqrestore(&nets[netid].lock, flags);
        rnet->open = true;

      out:
        return rc;
}

static int rionet_close(struct net_device *ndev)
{
        struct rionet_private *rnet = netdev_priv(ndev);
        struct rionet_peer *peer;
        unsigned char netid = rnet->mport->id;
        unsigned long flags;
        int i;

        if (netif_msg_ifup(rnet))
                printk(KERN_INFO "%s: close %s\n", DRV_NAME, ndev->name);

        netif_stop_queue(ndev);
        netif_carrier_off(ndev);
        rnet->open = false;

        for (i = 0; i < RIONET_RX_RING_SIZE; i++)
                kfree_skb(rnet->rx_skb[i]);

        spin_lock_irqsave(&nets[netid].lock, flags);
        list_for_each_entry(peer, &nets[netid].peers, node) {
                if (nets[netid].active[peer->rdev->destid]) {
                        rio_send_doorbell(peer->rdev, RIONET_DOORBELL_LEAVE);
                        nets[netid].active[peer->rdev->destid] = NULL;
                }
                if (peer->res)
                        rio_release_outb_dbell(peer->rdev, peer->res);
        }
        spin_unlock_irqrestore(&nets[netid].lock, flags);

        rio_release_inb_dbell(rnet->mport, RIONET_DOORBELL_JOIN,
                              RIONET_DOORBELL_LEAVE);
        rio_release_inb_mbox(rnet->mport, RIONET_MAILBOX);
        rio_release_outb_mbox(rnet->mport, RIONET_MAILBOX);

        return 0;
}

static void rionet_remove_dev(struct device *dev, struct subsys_interface *sif)
{
        struct rio_dev *rdev = to_rio_dev(dev);
        unsigned char netid = rdev->net->hport->id;
        struct rionet_peer *peer;
        int state, found = 0;
        unsigned long flags;

        if (!dev_rionet_capable(rdev))
                return;

        spin_lock_irqsave(&nets[netid].lock, flags);
        list_for_each_entry(peer, &nets[netid].peers, node) {
                if (peer->rdev == rdev) {
                        list_del(&peer->node);
                        if (nets[netid].active[rdev->destid]) {
                                state = atomic_read(&rdev->state);
                                if (state != RIO_DEVICE_GONE &&
                                    state != RIO_DEVICE_INITIALIZING) {
                                        rio_send_doorbell(rdev,
                                                        RIONET_DOORBELL_LEAVE);
                                }
                                nets[netid].active[rdev->destid] = NULL;
                                nets[netid].nact--;
                        }
                        found = 1;
                        break;
                }
        }
        spin_unlock_irqrestore(&nets[netid].lock, flags);

        if (found) {
                if (peer->res)
                        rio_release_outb_dbell(rdev, peer->res);
                kfree(peer);
        }
}

static void rionet_get_drvinfo(struct net_device *ndev,
                               struct ethtool_drvinfo *info)
{
        struct rionet_private *rnet = netdev_priv(ndev);

        strscpy(info->driver, DRV_NAME, sizeof(info->driver));
        strscpy(info->version, DRV_VERSION, sizeof(info->version));
        strscpy(info->fw_version, "n/a", sizeof(info->fw_version));
        strscpy(info->bus_info, rnet->mport->name, sizeof(info->bus_info));
}

static u32 rionet_get_msglevel(struct net_device *ndev)
{
        struct rionet_private *rnet = netdev_priv(ndev);

        return rnet->msg_enable;
}

static void rionet_set_msglevel(struct net_device *ndev, u32 value)
{
        struct rionet_private *rnet = netdev_priv(ndev);

        rnet->msg_enable = value;
}

static const struct ethtool_ops rionet_ethtool_ops = {
        .get_drvinfo = rionet_get_drvinfo,
        .get_msglevel = rionet_get_msglevel,
        .set_msglevel = rionet_set_msglevel,
        .get_link = ethtool_op_get_link,
};

static const struct net_device_ops rionet_netdev_ops = {
        .ndo_open               = rionet_open,
        .ndo_stop               = rionet_close,
        .ndo_start_xmit         = rionet_start_xmit,
        .ndo_validate_addr      = eth_validate_addr,
        .ndo_set_mac_address    = eth_mac_addr,
};

static int rionet_setup_netdev(struct rio_mport *mport, struct net_device *ndev)
{
        int rc = 0;
        struct rionet_private *rnet;
        u8 addr[ETH_ALEN];
        u16 device_id;
        const size_t rionet_active_bytes = sizeof(void *) *
                                RIO_MAX_ROUTE_ENTRIES(mport->sys_size);

        nets[mport->id].active = (struct rio_dev **)__get_free_pages(GFP_KERNEL,
                                                get_order(rionet_active_bytes));
        if (!nets[mport->id].active) {
                rc = -ENOMEM;
                goto out;
        }
        memset((void *)nets[mport->id].active, 0, rionet_active_bytes);

        /* Set up private area */
        rnet = netdev_priv(ndev);
        rnet->mport = mport;
        rnet->open = false;

        /* Set the default MAC address */
        device_id = rio_local_get_device_id(mport);
        addr[0] = 0x00;
        addr[1] = 0x01;
        addr[2] = 0x00;
        addr[3] = 0x01;
        addr[4] = device_id >> 8;
        addr[5] = device_id & 0xff;
        eth_hw_addr_set(ndev, addr);

        ndev->netdev_ops = &rionet_netdev_ops;
        ndev->mtu = RIONET_MAX_MTU;
        /* MTU range: 68 - 4082 */
        ndev->min_mtu = ETH_MIN_MTU;
        ndev->max_mtu = RIONET_MAX_MTU;
        ndev->lltx = true;
        SET_NETDEV_DEV(ndev, &mport->dev);
        ndev->ethtool_ops = &rionet_ethtool_ops;

        spin_lock_init(&rnet->lock);
        spin_lock_init(&rnet->tx_lock);

        rnet->msg_enable = RIONET_DEFAULT_MSGLEVEL;

        rc = register_netdev(ndev);
        if (rc != 0) {
                free_pages((unsigned long)nets[mport->id].active,
                           get_order(rionet_active_bytes));
                goto out;
        }

        printk(KERN_INFO "%s: %s %s Version %s, MAC %pM, %s\n",
               ndev->name,
               DRV_NAME,
               DRV_DESC,
               DRV_VERSION,
               ndev->dev_addr,
               mport->name);

      out:
        return rc;
}

static int rionet_add_dev(struct device *dev, struct subsys_interface *sif)
{
        int rc = -ENODEV;
        u32 lsrc_ops, ldst_ops;
        struct rionet_peer *peer;
        struct net_device *ndev = NULL;
        struct rio_dev *rdev = to_rio_dev(dev);
        unsigned char netid = rdev->net->hport->id;

        if (netid >= RIONET_MAX_NETS)
                return rc;

        /*
         * If first time through this net, make sure local device is rionet
         * capable and setup netdev (this step will be skipped in later probes
         * on the same net).
         */
        if (!nets[netid].ndev) {
                rio_local_read_config_32(rdev->net->hport, RIO_SRC_OPS_CAR,
                                         &lsrc_ops);
                rio_local_read_config_32(rdev->net->hport, RIO_DST_OPS_CAR,
                                         &ldst_ops);
                if (!is_rionet_capable(lsrc_ops, ldst_ops)) {
                        printk(KERN_ERR
                               "%s: local device %s is not network capable\n",
                               DRV_NAME, rdev->net->hport->name);
                        goto out;
                }

                /* Allocate our net_device structure */
                ndev = alloc_etherdev(sizeof(struct rionet_private));
                if (ndev == NULL) {
                        rc = -ENOMEM;
                        goto out;
                }

                rc = rionet_setup_netdev(rdev->net->hport, ndev);
                if (rc) {
                        printk(KERN_ERR "%s: failed to setup netdev (rc=%d)\n",
                               DRV_NAME, rc);
                        free_netdev(ndev);
                        goto out;
                }

                INIT_LIST_HEAD(&nets[netid].peers);
                spin_lock_init(&nets[netid].lock);
                nets[netid].nact = 0;
                nets[netid].ndev = ndev;
        }

        /*
         * If the remote device has mailbox/doorbell capabilities,
         * add it to the peer list.
         */
        if (dev_rionet_capable(rdev)) {
                struct rionet_private *rnet;
                unsigned long flags;

                rnet = netdev_priv(nets[netid].ndev);

                peer = kzalloc_obj(*peer);
                if (!peer) {
                        rc = -ENOMEM;
                        goto out;
                }
                peer->rdev = rdev;
                peer->res = rio_request_outb_dbell(peer->rdev,
                                                RIONET_DOORBELL_JOIN,
                                                RIONET_DOORBELL_LEAVE);
                if (!peer->res) {
                        pr_err("%s: error requesting doorbells\n", DRV_NAME);
                        kfree(peer);
                        rc = -ENOMEM;
                        goto out;
                }

                spin_lock_irqsave(&nets[netid].lock, flags);
                list_add_tail(&peer->node, &nets[netid].peers);
                spin_unlock_irqrestore(&nets[netid].lock, flags);
                pr_debug("%s: %s add peer %s\n",
                         DRV_NAME, __func__, rio_name(rdev));

                /* If netdev is already opened, send join request to new peer */
                if (rnet->open)
                        rio_send_doorbell(peer->rdev, RIONET_DOORBELL_JOIN);
        }

        return 0;
out:
        return rc;
}

static int rionet_shutdown(struct notifier_block *nb, unsigned long code,
                           void *unused)
{
        struct rionet_peer *peer;
        unsigned long flags;
        int i;

        pr_debug("%s: %s\n", DRV_NAME, __func__);

        for (i = 0; i < RIONET_MAX_NETS; i++) {
                if (!nets[i].ndev)
                        continue;

                spin_lock_irqsave(&nets[i].lock, flags);
                list_for_each_entry(peer, &nets[i].peers, node) {
                        if (nets[i].active[peer->rdev->destid]) {
                                rio_send_doorbell(peer->rdev,
                                                  RIONET_DOORBELL_LEAVE);
                                nets[i].active[peer->rdev->destid] = NULL;
                        }
                }
                spin_unlock_irqrestore(&nets[i].lock, flags);
        }

        return NOTIFY_DONE;
}

static void rionet_remove_mport(struct device *dev)
{
        struct rio_mport *mport = to_rio_mport(dev);
        struct net_device *ndev;
        int id = mport->id;

        pr_debug("%s %s\n", __func__, mport->name);

        WARN(nets[id].nact, "%s called when connected to %d peers\n",
             __func__, nets[id].nact);
        WARN(!nets[id].ndev, "%s called for mport without NDEV\n",
             __func__);

        if (nets[id].ndev) {
                ndev = nets[id].ndev;
                netif_stop_queue(ndev);
                unregister_netdev(ndev);

                free_pages((unsigned long)nets[id].active,
                           get_order(sizeof(void *) *
                           RIO_MAX_ROUTE_ENTRIES(mport->sys_size)));
                nets[id].active = NULL;
                free_netdev(ndev);
                nets[id].ndev = NULL;
        }
}

#ifdef MODULE
static struct rio_device_id rionet_id_table[] = {
        {RIO_DEVICE(RIO_ANY_ID, RIO_ANY_ID)},
        { 0, }  /* terminate list */
};

MODULE_DEVICE_TABLE(rapidio, rionet_id_table);
#endif

static struct subsys_interface rionet_interface = {
        .name           = "rionet",
        .subsys         = &rio_bus_type,
        .add_dev        = rionet_add_dev,
        .remove_dev     = rionet_remove_dev,
};

static struct notifier_block rionet_notifier = {
        .notifier_call = rionet_shutdown,
};

/* the rio_mport_interface is used to handle local mport devices */
static struct class_interface rio_mport_interface __refdata = {
        .class = &rio_mport_class,
        .add_dev = NULL,
        .remove_dev = rionet_remove_mport,
};

static int __init rionet_init(void)
{
        int ret;

        ret = register_reboot_notifier(&rionet_notifier);
        if (ret) {
                pr_err("%s: failed to register reboot notifier (err=%d)\n",
                       DRV_NAME, ret);
                return ret;
        }

        ret = class_interface_register(&rio_mport_interface);
        if (ret) {
                pr_err("%s: class_interface_register error: %d\n",
                       DRV_NAME, ret);
                return ret;
        }

        return subsys_interface_register(&rionet_interface);
}

static void __exit rionet_exit(void)
{
        unregister_reboot_notifier(&rionet_notifier);
        subsys_interface_unregister(&rionet_interface);
        class_interface_unregister(&rio_mport_interface);
}

late_initcall(rionet_init);
module_exit(rionet_exit);