Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6

[platform/adaptation/renesas_rcar/renesas_kernel.git] / net / irda / irlap_event.c

/*********************************************************************
 *
 * Filename:      irlap_event.c
 * Version:       0.9
 * Description:   IrLAP state machine implementation
 * Status:        Experimental.
 * Author:        Dag Brattli <dag@brattli.net>
 * Created at:    Sat Aug 16 00:59:29 1997
 * Modified at:   Sat Dec 25 21:07:57 1999
 * Modified by:   Dag Brattli <dag@brattli.net>
 *
 *     Copyright (c) 1998-2000 Dag Brattli <dag@brattli.net>,
 *     Copyright (c) 1998      Thomas Davis <ratbert@radiks.net>
 *     All Rights Reserved.
 *     Copyright (c) 2000-2003 Jean Tourrilhes <jt@hpl.hp.com>
 *
 *     This program is free software; you can redistribute it and/or
 *     modify it under the terms of the GNU General Public License as
 *     published by the Free Software Foundation; either version 2 of
 *     the License, or (at your option) any later version.
 *
 *     Neither Dag Brattli nor University of Tromsø admit liability nor
 *     provide warranty for any of this software. This material is
 *     provided "AS-IS" and at no charge.
 *
 ********************************************************************/

#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/skbuff.h>

#include <net/irda/irda.h>
#include <net/irda/irlap_event.h>

#include <net/irda/timer.h>
#include <net/irda/irlap.h>
#include <net/irda/irlap_frame.h>
#include <net/irda/qos.h>
#include <net/irda/parameters.h>
#include <net/irda/irlmp.h>             /* irlmp_flow_indication(), ... */

#include <net/irda/irda_device.h>

#ifdef CONFIG_IRDA_FAST_RR
int sysctl_fast_poll_increase = 50;
#endif

static int irlap_state_ndm    (struct irlap_cb *self, IRLAP_EVENT event,
                               struct sk_buff *skb, struct irlap_info *info);
static int irlap_state_query  (struct irlap_cb *self, IRLAP_EVENT event,
                               struct sk_buff *skb, struct irlap_info *info);
static int irlap_state_reply  (struct irlap_cb *self, IRLAP_EVENT event,
                               struct sk_buff *skb, struct irlap_info *info);
static int irlap_state_conn   (struct irlap_cb *self, IRLAP_EVENT event,
                               struct sk_buff *skb, struct irlap_info *info);
static int irlap_state_setup  (struct irlap_cb *self, IRLAP_EVENT event,
                               struct sk_buff *skb, struct irlap_info *info);
static int irlap_state_offline(struct irlap_cb *self, IRLAP_EVENT event,
                               struct sk_buff *skb, struct irlap_info *info);
static int irlap_state_xmit_p (struct irlap_cb *self, IRLAP_EVENT event,
                               struct sk_buff *skb, struct irlap_info *info);
static int irlap_state_pclose (struct irlap_cb *self, IRLAP_EVENT event,
                               struct sk_buff *skb, struct irlap_info *info);
static int irlap_state_nrm_p  (struct irlap_cb *self, IRLAP_EVENT event,
                               struct sk_buff *skb, struct irlap_info *info);
static int irlap_state_reset_wait(struct irlap_cb *self, IRLAP_EVENT event,
                                  struct sk_buff *skb, struct irlap_info *info);
static int irlap_state_reset  (struct irlap_cb *self, IRLAP_EVENT event,
                               struct sk_buff *skb, struct irlap_info *info);
static int irlap_state_nrm_s  (struct irlap_cb *self, IRLAP_EVENT event,
                               struct sk_buff *skb, struct irlap_info *info);
static int irlap_state_xmit_s (struct irlap_cb *self, IRLAP_EVENT event,
                               struct sk_buff *skb, struct irlap_info *info);
static int irlap_state_sclose (struct irlap_cb *self, IRLAP_EVENT event,
                               struct sk_buff *skb, struct irlap_info *info);
static int irlap_state_reset_check(struct irlap_cb *, IRLAP_EVENT event,
                                   struct sk_buff *, struct irlap_info *);

#ifdef CONFIG_IRDA_DEBUG
static const char *irlap_event[] = {
        "DISCOVERY_REQUEST",
        "CONNECT_REQUEST",
        "CONNECT_RESPONSE",
        "DISCONNECT_REQUEST",
        "DATA_REQUEST",
        "RESET_REQUEST",
        "RESET_RESPONSE",
        "SEND_I_CMD",
        "SEND_UI_FRAME",
        "RECV_DISCOVERY_XID_CMD",
        "RECV_DISCOVERY_XID_RSP",
        "RECV_SNRM_CMD",
        "RECV_TEST_CMD",
        "RECV_TEST_RSP",
        "RECV_UA_RSP",
        "RECV_DM_RSP",
        "RECV_RD_RSP",
        "RECV_I_CMD",
        "RECV_I_RSP",
        "RECV_UI_FRAME",
        "RECV_FRMR_RSP",
        "RECV_RR_CMD",
        "RECV_RR_RSP",
        "RECV_RNR_CMD",
        "RECV_RNR_RSP",
        "RECV_REJ_CMD",
        "RECV_REJ_RSP",
        "RECV_SREJ_CMD",
        "RECV_SREJ_RSP",
        "RECV_DISC_CMD",
        "SLOT_TIMER_EXPIRED",
        "QUERY_TIMER_EXPIRED",
        "FINAL_TIMER_EXPIRED",
        "POLL_TIMER_EXPIRED",
        "DISCOVERY_TIMER_EXPIRED",
        "WD_TIMER_EXPIRED",
        "BACKOFF_TIMER_EXPIRED",
        "MEDIA_BUSY_TIMER_EXPIRED",
};
#endif  /* CONFIG_IRDA_DEBUG */

const char *irlap_state[] = {
        "LAP_NDM",
        "LAP_QUERY",
        "LAP_REPLY",
        "LAP_CONN",
        "LAP_SETUP",
        "LAP_OFFLINE",
        "LAP_XMIT_P",
        "LAP_PCLOSE",
        "LAP_NRM_P",
        "LAP_RESET_WAIT",
        "LAP_RESET",
        "LAP_NRM_S",
        "LAP_XMIT_S",
        "LAP_SCLOSE",
        "LAP_RESET_CHECK",
};

static int (*state[])(struct irlap_cb *self, IRLAP_EVENT event,
                      struct sk_buff *skb, struct irlap_info *info) =
{
        irlap_state_ndm,
        irlap_state_query,
        irlap_state_reply,
        irlap_state_conn,
        irlap_state_setup,
        irlap_state_offline,
        irlap_state_xmit_p,
        irlap_state_pclose,
        irlap_state_nrm_p,
        irlap_state_reset_wait,
        irlap_state_reset,
        irlap_state_nrm_s,
        irlap_state_xmit_s,
        irlap_state_sclose,
        irlap_state_reset_check,
};

/*
 * Function irda_poll_timer_expired (data)
 *
 *    Poll timer has expired. Normally we must now send a RR frame to the
 *    remote device
 */
static void irlap_poll_timer_expired(void *data)
{
        struct irlap_cb *self = (struct irlap_cb *) data;

        IRDA_ASSERT(self != NULL, return;);
        IRDA_ASSERT(self->magic == LAP_MAGIC, return;);

        irlap_do_event(self, POLL_TIMER_EXPIRED, NULL, NULL);
}

/*
 * Calculate and set time before we will have to send back the pf bit
 * to the peer. Use in primary.
 * Make sure that state is XMIT_P/XMIT_S when calling this function
 * (and that nobody messed up with the state). - Jean II
 */
static void irlap_start_poll_timer(struct irlap_cb *self, int timeout)
{
        IRDA_ASSERT(self != NULL, return;);
        IRDA_ASSERT(self->magic == LAP_MAGIC, return;);

#ifdef CONFIG_IRDA_FAST_RR
        /*
         * Send out the RR frames faster if our own transmit queue is empty, or
         * if the peer is busy. The effect is a much faster conversation
         */
        if (skb_queue_empty(&self->txq) || self->remote_busy) {
                if (self->fast_RR == TRUE) {
                        /*
                         *  Assert that the fast poll timer has not reached the
                         *  normal poll timer yet
                         */
                        if (self->fast_RR_timeout < timeout) {
                                /*
                                 *  FIXME: this should be a more configurable
                                 *         function
                                 */
                                self->fast_RR_timeout +=
                                        (sysctl_fast_poll_increase * HZ/1000);

                                /* Use this fast(er) timeout instead */
                                timeout = self->fast_RR_timeout;
                        }
                } else {
                        self->fast_RR = TRUE;

                        /* Start with just 0 ms */
                        self->fast_RR_timeout = 0;
                        timeout = 0;
                }
        } else
                self->fast_RR = FALSE;

        IRDA_DEBUG(3, "%s(), timeout=%d (%ld)\n", __func__, timeout, jiffies);
#endif /* CONFIG_IRDA_FAST_RR */

        if (timeout == 0)
                irlap_do_event(self, POLL_TIMER_EXPIRED, NULL, NULL);
        else
                irda_start_timer(&self->poll_timer, timeout, self,
                                 irlap_poll_timer_expired);
}

/*
 * Function irlap_do_event (event, skb, info)
 *
 *    Rushes through the state machine without any delay. If state == XMIT
 *    then send queued data frames.
 */
void irlap_do_event(struct irlap_cb *self, IRLAP_EVENT event,
                    struct sk_buff *skb, struct irlap_info *info)
{
        int ret;

        if (!self || self->magic != LAP_MAGIC)
                return;

        IRDA_DEBUG(3, "%s(), event = %s, state = %s\n", __func__,
                   irlap_event[event], irlap_state[self->state]);

        ret = (*state[self->state])(self, event, skb, info);

        /*
         *  Check if there are any pending events that needs to be executed
         */
        switch (self->state) {
        case LAP_XMIT_P: /* FALLTHROUGH */
        case LAP_XMIT_S:
                /*
                 * We just received the pf bit and are at the beginning
                 * of a new LAP transmit window.
                 * Check if there are any queued data frames, and do not
                 * try to disconnect link if we send any data frames, since
                 * that will change the state away form XMIT
                 */
                IRDA_DEBUG(2, "%s() : queue len = %d\n", __func__,
                           skb_queue_len(&self->txq));

                if (!skb_queue_empty(&self->txq)) {
                        /* Prevent race conditions with irlap_data_request() */
                        self->local_busy = TRUE;

                        /* Theory of operation.
                         * We send frames up to when we fill the window or
                         * reach line capacity. Those frames will queue up
                         * in the device queue, and the driver will slowly
                         * send them.
                         * After each frame that we send, we poll the higher
                         * layer for more data. It's the right time to do
                         * that because the link layer need to perform the mtt
                         * and then send the first frame, so we can afford
                         * to send a bit of time in kernel space.
                         * The explicit flow indication allow to minimise
                         * buffers (== lower latency), to avoid higher layer
                         * polling via timers (== less context switches) and
                         * to implement a crude scheduler - Jean II */

                        /* Try to send away all queued data frames */
                        while ((skb = skb_dequeue(&self->txq)) != NULL) {
                                /* Send one frame */
                                ret = (*state[self->state])(self, SEND_I_CMD,
                                                            skb, NULL);
                                /* Drop reference count.
                                 * It will be increase as needed in
                                 * irlap_send_data_xxx() */
                                kfree_skb(skb);

                                /* Poll the higher layers for one more frame */
                                irlmp_flow_indication(self->notify.instance,
                                                      FLOW_START);

                                if (ret == -EPROTO)
                                        break; /* Try again later! */
                        }
                        /* Finished transmitting */
                        self->local_busy = FALSE;
                } else if (self->disconnect_pending) {
                        self->disconnect_pending = FALSE;

                        ret = (*state[self->state])(self, DISCONNECT_REQUEST,
                                                    NULL, NULL);
                }
                break;
/*      case LAP_NDM: */
/*      case LAP_CONN: */
/*      case LAP_RESET_WAIT: */
/*      case LAP_RESET_CHECK: */
        default:
                break;
        }
}

/*
 * Function irlap_state_ndm (event, skb, frame)
 *
 *    NDM (Normal Disconnected Mode) state
 *
 */
static int irlap_state_ndm(struct irlap_cb *self, IRLAP_EVENT event,
                           struct sk_buff *skb, struct irlap_info *info)
{
        discovery_t *discovery_rsp;
        int ret = 0;

        IRDA_ASSERT(self != NULL, return -1;);
        IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);

        switch (event) {
        case CONNECT_REQUEST:
                IRDA_ASSERT(self->netdev != NULL, return -1;);

                if (self->media_busy) {
                        /* Note : this will never happen, because we test
                         * media busy in irlap_connect_request() and
                         * postpone the event... - Jean II */
                        IRDA_DEBUG(0, "%s(), CONNECT_REQUEST: media busy!\n",
                                   __func__);

                        /* Always switch state before calling upper layers */
                        irlap_next_state(self, LAP_NDM);

                        irlap_disconnect_indication(self, LAP_MEDIA_BUSY);
                } else {
                        irlap_send_snrm_frame(self, &self->qos_rx);

                        /* Start Final-bit timer */
                        irlap_start_final_timer(self, self->final_timeout);

                        self->retry_count = 0;
                        irlap_next_state(self, LAP_SETUP);
                }
                break;
        case RECV_SNRM_CMD:
                /* Check if the frame contains and I field */
                if (info) {
                        self->daddr = info->daddr;
                        self->caddr = info->caddr;

                        irlap_next_state(self, LAP_CONN);

                        irlap_connect_indication(self, skb);
                } else {
                        IRDA_DEBUG(0, "%s(), SNRM frame does not "
                                   "contain an I field!\n", __func__);
                }
                break;
        case DISCOVERY_REQUEST:
                IRDA_ASSERT(info != NULL, return -1;);

                if (self->media_busy) {
                        IRDA_DEBUG(1, "%s(), DISCOVERY_REQUEST: media busy!\n",
                                   __func__);
                        /* irlap->log.condition = MEDIA_BUSY; */

                        /* This will make IrLMP try again */
                        irlap_discovery_confirm(self, NULL);
                        /* Note : the discovery log is not cleaned up here,
                         * it will be done in irlap_discovery_request()
                         * Jean II */
                        return 0;
                }

                self->S = info->S;
                self->s = info->s;
                irlap_send_discovery_xid_frame(self, info->S, info->s, TRUE,
                                               info->discovery);
                self->frame_sent = FALSE;
                self->s++;

                irlap_start_slot_timer(self, self->slot_timeout);
                irlap_next_state(self, LAP_QUERY);
                break;
        case RECV_DISCOVERY_XID_CMD:
                IRDA_ASSERT(info != NULL, return -1;);

                /* Assert that this is not the final slot */
                if (info->s <= info->S) {
                        self->slot = irlap_generate_rand_time_slot(info->S,
                                                                   info->s);
                        if (self->slot == info->s) {
                                discovery_rsp = irlmp_get_discovery_response();
                                discovery_rsp->data.daddr = info->daddr;

                                irlap_send_discovery_xid_frame(self, info->S,
                                                               self->slot,
                                                               FALSE,
                                                               discovery_rsp);
                                self->frame_sent = TRUE;
                        } else
                                self->frame_sent = FALSE;

                        /*
                         * Go to reply state until end of discovery to
                         * inhibit our own transmissions. Set the timer
                         * to not stay forever there... Jean II
                         */
                        irlap_start_query_timer(self, info->S, info->s);
                        irlap_next_state(self, LAP_REPLY);
                } else {
                /* This is the final slot. How is it possible ?
                 * This would happen is both discoveries are just slightly
                 * offset (if they are in sync, all packets are lost).
                 * Most often, all the discovery requests will be received
                 * in QUERY state (see my comment there), except for the
                 * last frame that will come here.
                 * The big trouble when it happen is that active discovery
                 * doesn't happen, because nobody answer the discoveries
                 * frame of the other guy, so the log shows up empty.
                 * What should we do ?
                 * Not much. It's too late to answer those discovery frames,
                 * so we just pass the info to IrLMP who will put it in the
                 * log (and post an event).
                 * Another cause would be devices that do discovery much
                 * slower than us, however the latest fixes should minimise
                 * those cases...
                 * Jean II
                 */
                        IRDA_DEBUG(1, "%s(), Receiving final discovery request, missed the discovery slots :-(\n", __func__);

                        /* Last discovery request -> in the log */
                        irlap_discovery_indication(self, info->discovery);
                }
                break;
        case MEDIA_BUSY_TIMER_EXPIRED:
                /* A bunch of events may be postponed because the media is
                 * busy (usually immediately after we close a connection),
                 * or while we are doing discovery (state query/reply).
                 * In all those cases, the media busy flag will be cleared
                 * when it's OK for us to process those postponed events.
                 * This event is not mentioned in the state machines in the
                 * IrLAP spec. It's because they didn't consider Ultra and
                 * postponing connection request is optional.
                 * Jean II */
#ifdef CONFIG_IRDA_ULTRA
                /* Send any pending Ultra frames if any */
                if (!skb_queue_empty(&self->txq_ultra)) {
                        /* We don't send the frame, just post an event.
                         * Also, previously this code was in timer.c...
                         * Jean II */
                        ret = (*state[self->state])(self, SEND_UI_FRAME,
                                                    NULL, NULL);
                }
#endif /* CONFIG_IRDA_ULTRA */
                /* Check if we should try to connect.
                 * This code was previously in irlap_do_event() */
                if (self->connect_pending) {
                        self->connect_pending = FALSE;

                        /* This one *should* not pend in this state, except
                         * if a socket try to connect and immediately
                         * disconnect. - clear - Jean II */
                        if (self->disconnect_pending)
                                irlap_disconnect_indication(self, LAP_DISC_INDICATION);
                        else
                                ret = (*state[self->state])(self,
                                                            CONNECT_REQUEST,
                                                            NULL, NULL);
                        self->disconnect_pending = FALSE;
                }
                /* Note : one way to test if this code works well (including
                 * media busy and small busy) is to create a user space
                 * application generating an Ultra packet every 3.05 sec (or
                 * 2.95 sec) and to see how it interact with discovery.
                 * It's fairly easy to check that no packet is lost, that the
                 * packets are postponed during discovery and that after
                 * discovery indication you have a 100ms "gap".
                 * As connection request and Ultra are now processed the same
                 * way, this avoid the tedious job of trying IrLAP connection
                 * in all those cases...
                 * Jean II */
                break;
#ifdef CONFIG_IRDA_ULTRA
        case SEND_UI_FRAME:
        {
                int i;
                /* Only allowed to repeat an operation twice */
                for (i=0; ((i<2) && (self->media_busy == FALSE)); i++) {
                        skb = skb_dequeue(&self->txq_ultra);
                        if (skb)
                                irlap_send_ui_frame(self, skb, CBROADCAST,
                                                    CMD_FRAME);
                        else
                                break;
                        /* irlap_send_ui_frame() won't increase skb reference
                         * count, so no dev_kfree_skb() - Jean II */
                }
                if (i == 2) {
                        /* Force us to listen 500 ms again */
                        irda_device_set_media_busy(self->netdev, TRUE);
                }
                break;
        }
        case RECV_UI_FRAME:
                /* Only accept broadcast frames in NDM mode */
                if (info->caddr != CBROADCAST) {
                        IRDA_DEBUG(0, "%s(), not a broadcast frame!\n",
                                   __func__);
                } else
                        irlap_unitdata_indication(self, skb);
                break;
#endif /* CONFIG_IRDA_ULTRA */
        case RECV_TEST_CMD:
                /* Remove test frame header */
                skb_pull(skb, sizeof(struct test_frame));

                /*
                 * Send response. This skb will not be sent out again, and
                 * will only be used to send out the same info as the cmd
                 */
                irlap_send_test_frame(self, CBROADCAST, info->daddr, skb);
                break;
        case RECV_TEST_RSP:
                IRDA_DEBUG(0, "%s() not implemented!\n", __func__);
                break;
        default:
                IRDA_DEBUG(2, "%s(), Unknown event %s\n", __func__,
                           irlap_event[event]);

                ret = -1;
                break;
        }
        return ret;
}

/*
 * Function irlap_state_query (event, skb, info)
 *
 *    QUERY state
 *
 */
static int irlap_state_query(struct irlap_cb *self, IRLAP_EVENT event,
                             struct sk_buff *skb, struct irlap_info *info)
{
        int ret = 0;

        IRDA_ASSERT(self != NULL, return -1;);
        IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);

        switch (event) {
        case RECV_DISCOVERY_XID_RSP:
                IRDA_ASSERT(info != NULL, return -1;);
                IRDA_ASSERT(info->discovery != NULL, return -1;);

                IRDA_DEBUG(4, "%s(), daddr=%08x\n", __func__,
                           info->discovery->data.daddr);

                if (!self->discovery_log) {
                        IRDA_WARNING("%s: discovery log is gone! "
                                     "maybe the discovery timeout has been set"
                                     " too short?\n", __func__);
                        break;
                }
                hashbin_insert(self->discovery_log,
                               (irda_queue_t *) info->discovery,
                               info->discovery->data.daddr, NULL);

                /* Keep state */
                /* irlap_next_state(self, LAP_QUERY);  */

                break;
        case RECV_DISCOVERY_XID_CMD:
                /* Yes, it is possible to receive those frames in this mode.
                 * Note that most often the last discovery request won't
                 * occur here but in NDM state (see my comment there).
                 * What should we do ?
                 * Not much. We are currently performing our own discovery,
                 * therefore we can't answer those frames. We don't want
                 * to change state either. We just pass the info to
                 * IrLMP who will put it in the log (and post an event).
                 * Jean II
                 */

                IRDA_ASSERT(info != NULL, return -1;);

                IRDA_DEBUG(1, "%s(), Receiving discovery request (s = %d) while performing discovery :-(\n", __func__, info->s);

                /* Last discovery request ? */
                if (info->s == 0xff)
                        irlap_discovery_indication(self, info->discovery);
                break;
        case SLOT_TIMER_EXPIRED:
                /*
                 * Wait a little longer if we detect an incoming frame. This
                 * is not mentioned in the spec, but is a good thing to do,
                 * since we want to work even with devices that violate the
                 * timing requirements.
                 */
                if (irda_device_is_receiving(self->netdev) && !self->add_wait) {
                        IRDA_DEBUG(2, "%s(), device is slow to answer, "
                                   "waiting some more!\n", __func__);
                        irlap_start_slot_timer(self, msecs_to_jiffies(10));
                        self->add_wait = TRUE;
                        return ret;
                }
                self->add_wait = FALSE;

                if (self->s < self->S) {
                        irlap_send_discovery_xid_frame(self, self->S,
                                                       self->s, TRUE,
                                                       self->discovery_cmd);
                        self->s++;
                        irlap_start_slot_timer(self, self->slot_timeout);

                        /* Keep state */
                        irlap_next_state(self, LAP_QUERY);
                } else {
                        /* This is the final slot! */
                        irlap_send_discovery_xid_frame(self, self->S, 0xff,
                                                       TRUE,
                                                       self->discovery_cmd);

                        /* Always switch state before calling upper layers */
                        irlap_next_state(self, LAP_NDM);

                        /*
                         *  We are now finished with the discovery procedure,
                         *  so now we must return the results
                         */
                        irlap_discovery_confirm(self, self->discovery_log);

                        /* IrLMP should now have taken care of the log */
                        self->discovery_log = NULL;
                }
                break;
        default:
                IRDA_DEBUG(2, "%s(), Unknown event %s\n", __func__,
                           irlap_event[event]);

                ret = -1;
                break;
        }
        return ret;
}

/*
 * Function irlap_state_reply (self, event, skb, info)
 *
 *    REPLY, we have received a XID discovery frame from a device and we
 *    are waiting for the right time slot to send a response XID frame
 *
 */
static int irlap_state_reply(struct irlap_cb *self, IRLAP_EVENT event,
                             struct sk_buff *skb, struct irlap_info *info)
{
        discovery_t *discovery_rsp;
        int ret=0;

        IRDA_DEBUG(4, "%s()\n", __func__);

        IRDA_ASSERT(self != NULL, return -1;);
        IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);

        switch (event) {
        case QUERY_TIMER_EXPIRED:
                IRDA_DEBUG(0, "%s(), QUERY_TIMER_EXPIRED <%ld>\n",
                           __func__, jiffies);
                irlap_next_state(self, LAP_NDM);
                break;
        case RECV_DISCOVERY_XID_CMD:
                IRDA_ASSERT(info != NULL, return -1;);
                /* Last frame? */
                if (info->s == 0xff) {
                        del_timer(&self->query_timer);

                        /* info->log.condition = REMOTE; */

                        /* Always switch state before calling upper layers */
                        irlap_next_state(self, LAP_NDM);

                        irlap_discovery_indication(self, info->discovery);
                } else {
                        /* If it's our slot, send our reply */
                        if ((info->s >= self->slot) && (!self->frame_sent)) {
                                discovery_rsp = irlmp_get_discovery_response();
                                discovery_rsp->data.daddr = info->daddr;

                                irlap_send_discovery_xid_frame(self, info->S,
                                                               self->slot,
                                                               FALSE,
                                                               discovery_rsp);

                                self->frame_sent = TRUE;
                        }
                        /* Readjust our timer to accomodate devices
                         * doing faster or slower discovery than us...
                         * Jean II */
                        irlap_start_query_timer(self, info->S, info->s);

                        /* Keep state */
                        //irlap_next_state(self, LAP_REPLY);
                }
                break;
        default:
                IRDA_DEBUG(1, "%s(), Unknown event %d, %s\n", __func__,
                           event, irlap_event[event]);

                ret = -1;
                break;
        }
        return ret;
}

/*
 * Function irlap_state_conn (event, skb, info)
 *
 *    CONN, we have received a SNRM command and is waiting for the upper
 *    layer to accept or refuse connection
 *
 */
static int irlap_state_conn(struct irlap_cb *self, IRLAP_EVENT event,
                            struct sk_buff *skb, struct irlap_info *info)
{
        int ret = 0;

        IRDA_DEBUG(4, "%s(), event=%s\n", __func__, irlap_event[ event]);

        IRDA_ASSERT(self != NULL, return -1;);
        IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);

        switch (event) {
        case CONNECT_RESPONSE:
                skb_pull(skb, sizeof(struct snrm_frame));

                IRDA_ASSERT(self->netdev != NULL, return -1;);

                irlap_qos_negotiate(self, skb);

                irlap_initiate_connection_state(self);

                /*
                 * Applying the parameters now will make sure we change speed
                 * *after* we have sent the next frame
                 */
                irlap_apply_connection_parameters(self, FALSE);

                /*
                 * Sending this frame will force a speed change after it has
                 * been sent (i.e. the frame will be sent at 9600).
                 */
                irlap_send_ua_response_frame(self, &self->qos_rx);

#if 0
                /*
                 * We are allowed to send two frames, but this may increase
                 * the connect latency, so lets not do it for now.
                 */
                /* This is full of good intentions, but doesn't work in
                 * practice.
                 * After sending the first UA response, we switch the
                 * dongle to the negotiated speed, which is usually
                 * different than 9600 kb/s.
                 * From there, there is two solutions :
                 * 1) The other end has received the first UA response :
                 * it will set up the connection, move to state LAP_NRM_P,
                 * and will ignore and drop the second UA response.
                 * Actually, it's even worse : the other side will almost
                 * immediately send a RR that will likely collide with the
                 * UA response (depending on negotiated turnaround).
                 * 2) The other end has not received the first UA response,
                 * will stay at 9600 and will never see the second UA response.
                 * Jean II */
                irlap_send_ua_response_frame(self, &self->qos_rx);
#endif

                /*
                 *  The WD-timer could be set to the duration of the P-timer
                 *  for this case, but it is recommended to use twice the
                 *  value (note 3 IrLAP p. 60).
                 */
                irlap_start_wd_timer(self, self->wd_timeout);
                irlap_next_state(self, LAP_NRM_S);

                break;
        case RECV_DISCOVERY_XID_CMD:
                IRDA_DEBUG(3, "%s(), event RECV_DISCOVER_XID_CMD!\n",
                           __func__);
                irlap_next_state(self, LAP_NDM);

                break;
        case DISCONNECT_REQUEST:
                IRDA_DEBUG(0, "%s(), Disconnect request!\n", __func__);
                irlap_send_dm_frame(self);
                irlap_next_state( self, LAP_NDM);
                irlap_disconnect_indication(self, LAP_DISC_INDICATION);
                break;
        default:
                IRDA_DEBUG(1, "%s(), Unknown event %d, %s\n", __func__,
                           event, irlap_event[event]);

                ret = -1;
                break;
        }

        return ret;
}

/*
 * Function irlap_state_setup (event, skb, frame)
 *
 *    SETUP state, The local layer has transmitted a SNRM command frame to
 *    a remote peer layer and is awaiting a reply .
 *
 */
static int irlap_state_setup(struct irlap_cb *self, IRLAP_EVENT event,
                             struct sk_buff *skb, struct irlap_info *info)
{
        int ret = 0;

        IRDA_DEBUG(4, "%s()\n", __func__);

        IRDA_ASSERT(self != NULL, return -1;);
        IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);

        switch (event) {
        case FINAL_TIMER_EXPIRED:
                if (self->retry_count < self->N3) {
/*
 *  Perform random backoff, Wait a random number of time units, minimum
 *  duration half the time taken to transmitt a SNRM frame, maximum duration
 *  1.5 times the time taken to transmit a SNRM frame. So this time should
 *  between 15 msecs and 45 msecs.
 */
                        irlap_start_backoff_timer(self, msecs_to_jiffies(20 +
                                                        (jiffies % 30)));
                } else {
                        /* Always switch state before calling upper layers */
                        irlap_next_state(self, LAP_NDM);

                        irlap_disconnect_indication(self, LAP_FOUND_NONE);
                }
                break;
        case BACKOFF_TIMER_EXPIRED:
                irlap_send_snrm_frame(self, &self->qos_rx);
                irlap_start_final_timer(self, self->final_timeout);
                self->retry_count++;
                break;
        case RECV_SNRM_CMD:
                IRDA_DEBUG(4, "%s(), SNRM battle!\n", __func__);

                IRDA_ASSERT(skb != NULL, return 0;);
                IRDA_ASSERT(info != NULL, return 0;);

                /*
                 *  The device with the largest device address wins the battle
                 *  (both have sent a SNRM command!)
                 */
                if (info &&(info->daddr > self->saddr)) {
                        del_timer(&self->final_timer);
                        irlap_initiate_connection_state(self);

                        IRDA_ASSERT(self->netdev != NULL, return -1;);

                        skb_pull(skb, sizeof(struct snrm_frame));

                        irlap_qos_negotiate(self, skb);

                        /* Send UA frame and then change link settings */
                        irlap_apply_connection_parameters(self, FALSE);
                        irlap_send_ua_response_frame(self, &self->qos_rx);

                        irlap_next_state(self, LAP_NRM_S);
                        irlap_connect_confirm(self, skb);

                        /*
                         *  The WD-timer could be set to the duration of the
                         *  P-timer for this case, but it is recommended
                         *  to use twice the value (note 3 IrLAP p. 60).
                         */
                        irlap_start_wd_timer(self, self->wd_timeout);
                } else {
                        /* We just ignore the other device! */
                        irlap_next_state(self, LAP_SETUP);
                }
                break;
        case RECV_UA_RSP:
                /* Stop F-timer */
                del_timer(&self->final_timer);

                /* Initiate connection state */
                irlap_initiate_connection_state(self);

                /* Negotiate connection parameters */
                IRDA_ASSERT(skb->len > 10, return -1;);

                skb_pull(skb, sizeof(struct ua_frame));

                IRDA_ASSERT(self->netdev != NULL, return -1;);

                irlap_qos_negotiate(self, skb);

                /* Set the new link setting *now* (before the rr frame) */
                irlap_apply_connection_parameters(self, TRUE);
                self->retry_count = 0;

                /* Wait for turnaround time to give a chance to the other
                 * device to be ready to receive us.
                 * Note : the time to switch speed is typically larger
                 * than the turnaround time, but as we don't have the other
                 * side speed switch time, that's our best guess...
                 * Jean II */
                irlap_wait_min_turn_around(self, &self->qos_tx);

                /* This frame will actually be sent at the new speed */
                irlap_send_rr_frame(self, CMD_FRAME);

                /* The timer is set to half the normal timer to quickly
                 * detect a failure to negociate the new connection
                 * parameters. IrLAP 6.11.3.2, note 3.
                 * Note that currently we don't process this failure
                 * properly, as we should do a quick disconnect.
                 * Jean II */
                irlap_start_final_timer(self, self->final_timeout/2);
                irlap_next_state(self, LAP_NRM_P);

                irlap_connect_confirm(self, skb);
                break;
        case RECV_DM_RSP:     /* FALLTHROUGH */
        case RECV_DISC_CMD:
                del_timer(&self->final_timer);
                irlap_next_state(self, LAP_NDM);

                irlap_disconnect_indication(self, LAP_DISC_INDICATION);
                break;
        default:
                IRDA_DEBUG(1, "%s(), Unknown event %d, %s\n", __func__,
                           event, irlap_event[event]);

                ret = -1;
                break;
        }
        return ret;
}

/*
 * Function irlap_state_offline (self, event, skb, info)
 *
 *    OFFLINE state, not used for now!
 *
 */
static int irlap_state_offline(struct irlap_cb *self, IRLAP_EVENT event,
                               struct sk_buff *skb, struct irlap_info *info)
{
        IRDA_DEBUG( 0, "%s(), Unknown event\n", __func__);

        return -1;
}

/*
 * Function irlap_state_xmit_p (self, event, skb, info)
 *
 *    XMIT, Only the primary station has right to transmit, and we
 *    therefore do not expect to receive any transmissions from other
 *    stations.
 *
 */
static int irlap_state_xmit_p(struct irlap_cb *self, IRLAP_EVENT event,
                              struct sk_buff *skb, struct irlap_info *info)
{
        int ret = 0;

        switch (event) {
        case SEND_I_CMD:
                /*
                 *  Only send frame if send-window > 0.
                 */
                if ((self->window > 0) && (!self->remote_busy)) {
                        int nextfit;
#ifdef CONFIG_IRDA_DYNAMIC_WINDOW
                        struct sk_buff *skb_next;

                        /* With DYNAMIC_WINDOW, we keep the window size
                         * maximum, and adapt on the packets we are sending.
                         * At 115k, we can send only 2 packets of 2048 bytes
                         * in a 500 ms turnaround. Without this option, we
                         * would always limit the window to 2. With this
                         * option, if we send smaller packets, we can send
                         * up to 7 of them (always depending on QoS).
                         * Jean II */

                        /* Look at the next skb. This is safe, as we are
                         * the only consumer of the Tx queue (if we are not,
                         * we have other problems) - Jean II */
                        skb_next = skb_peek(&self->txq);

                        /* Check if a subsequent skb exist and would fit in
                         * the current window (with respect to turnaround
                         * time).
                         * This allow us to properly mark the current packet
                         * with the pf bit, to avoid falling back on the
                         * second test below, and avoid waiting the
                         * end of the window and sending a extra RR.
                         * Note : (skb_next != NULL) <=> (skb_queue_len() > 0)
                         * Jean II */
                        nextfit = ((skb_next != NULL) &&
                                   ((skb_next->len + skb->len) <=
                                    self->bytes_left));

                        /*
                         * The current packet may not fit ! Because of test
                         * above, this should not happen any more !!!
                         *  Test if we have transmitted more bytes over the
                         *  link than its possible to do with the current
                         *  speed and turn-around-time.
                         */
                        if((!nextfit) && (skb->len > self->bytes_left)) {
                                IRDA_DEBUG(0, "%s(), Not allowed to transmit"
                                           " more bytes!\n", __func__);
                                /* Requeue the skb */
                                skb_queue_head(&self->txq, skb_get(skb));
                                /*
                                 *  We should switch state to LAP_NRM_P, but
                                 *  that is not possible since we must be sure
                                 *  that we poll the other side. Since we have
                                 *  used up our time, the poll timer should
                                 *  trigger anyway now, so we just wait for it
                                 *  DB
                                 */
                                /*
                                 * Sorry, but that's not totally true. If
                                 * we send 2000B packets, we may wait another
                                 * 1000B until our turnaround expire. That's
                                 * why we need to be proactive in avoiding
                                 * coming here. - Jean II
                                 */
                                return -EPROTO;
                        }

                        /* Substract space used by this skb */
                        self->bytes_left -= skb->len;
#else   /* CONFIG_IRDA_DYNAMIC_WINDOW */
                        /* Window has been adjusted for the max packet
                         * size, so much simpler... - Jean II */
                        nextfit = !skb_queue_empty(&self->txq);
#endif  /* CONFIG_IRDA_DYNAMIC_WINDOW */
                        /*
                         *  Send data with poll bit cleared only if window > 1
                         *  and there is more frames after this one to be sent
                         */
                        if ((self->window > 1) && (nextfit)) {
                                /* More packet to send in current window */
                                irlap_send_data_primary(self, skb);
                                irlap_next_state(self, LAP_XMIT_P);
                        } else {
                                /* Final packet of window */
                                irlap_send_data_primary_poll(self, skb);

                                /*
                                 * Make sure state machine does not try to send
                                 * any more frames
                                 */
                                ret = -EPROTO;
                        }
#ifdef CONFIG_IRDA_FAST_RR
                        /* Peer may want to reply immediately */
                        self->fast_RR = FALSE;
#endif /* CONFIG_IRDA_FAST_RR */
                } else {
                        IRDA_DEBUG(4, "%s(), Unable to send! remote busy?\n",
                                   __func__);
                        skb_queue_head(&self->txq, skb_get(skb));

                        /*
                         *  The next ret is important, because it tells
                         *  irlap_next_state _not_ to deliver more frames
                         */
                        ret = -EPROTO;
                }
                break;
        case POLL_TIMER_EXPIRED:
                IRDA_DEBUG(3, "%s(), POLL_TIMER_EXPIRED <%ld>\n",
                            __func__, jiffies);
                irlap_send_rr_frame(self, CMD_FRAME);
                /* Return to NRM properly - Jean II  */
                self->window = self->window_size;
#ifdef CONFIG_IRDA_DYNAMIC_WINDOW
                /* Allowed to transmit a maximum number of bytes again. */
                self->bytes_left = self->line_capacity;
#endif /* CONFIG_IRDA_DYNAMIC_WINDOW */
                irlap_start_final_timer(self, self->final_timeout);
                irlap_next_state(self, LAP_NRM_P);
                break;
        case DISCONNECT_REQUEST:
                del_timer(&self->poll_timer);
                irlap_wait_min_turn_around(self, &self->qos_tx);
                irlap_send_disc_frame(self);
                irlap_flush_all_queues(self);
                irlap_start_final_timer(self, self->final_timeout);
                self->retry_count = 0;
                irlap_next_state(self, LAP_PCLOSE);
                break;
        case DATA_REQUEST:
                /* Nothing to do, irlap_do_event() will send the packet
                 * when we return... - Jean II */
                break;
        default:
                IRDA_DEBUG(0, "%s(), Unknown event %s\n",
                           __func__, irlap_event[event]);

                ret = -EINVAL;
                break;
        }
        return ret;
}

/*
 * Function irlap_state_pclose (event, skb, info)
 *
 *    PCLOSE state
 */
static int irlap_state_pclose(struct irlap_cb *self, IRLAP_EVENT event,
                              struct sk_buff *skb, struct irlap_info *info)
{
        int ret = 0;

        IRDA_DEBUG(1, "%s()\n", __func__);

        IRDA_ASSERT(self != NULL, return -1;);
        IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);

        switch (event) {
        case RECV_UA_RSP: /* FALLTHROUGH */
        case RECV_DM_RSP:
                del_timer(&self->final_timer);

                /* Set new link parameters */
                irlap_apply_default_connection_parameters(self);

                /* Always switch state before calling upper layers */
                irlap_next_state(self, LAP_NDM);

                irlap_disconnect_indication(self, LAP_DISC_INDICATION);
                break;
        case FINAL_TIMER_EXPIRED:
                if (self->retry_count < self->N3) {
                        irlap_wait_min_turn_around(self, &self->qos_tx);
                        irlap_send_disc_frame(self);
                        irlap_start_final_timer(self, self->final_timeout);
                        self->retry_count++;
                        /* Keep state */
                } else {
                        irlap_apply_default_connection_parameters(self);

                        /*  Always switch state before calling upper layers */
                        irlap_next_state(self, LAP_NDM);

                        irlap_disconnect_indication(self, LAP_NO_RESPONSE);
                }
                break;
        default:
                IRDA_DEBUG(1, "%s(), Unknown event %d\n", __func__, event);

                ret = -1;
                break;
        }
        return ret;
}

/*
 * Function irlap_state_nrm_p (self, event, skb, info)
 *
 *   NRM_P (Normal Response Mode as Primary), The primary station has given
 *   permissions to a secondary station to transmit IrLAP resonse frames
 *   (by sending a frame with the P bit set). The primary station will not
 *   transmit any frames and is expecting to receive frames only from the
 *   secondary to which transmission permissions has been given.
 */
static int irlap_state_nrm_p(struct irlap_cb *self, IRLAP_EVENT event,
                             struct sk_buff *skb, struct irlap_info *info)
{
        int ret = 0;
        int ns_status;
        int nr_status;

        switch (event) {
        case RECV_I_RSP: /* Optimize for the common case */
                if (unlikely(skb->len <= LAP_ADDR_HEADER + LAP_CTRL_HEADER)) {
                        /*
                         * Input validation check: a stir4200/mcp2150
                         * combination sometimes results in an empty i:rsp.
                         * This makes no sense; we can just ignore the frame
                         * and send an rr:cmd immediately. This happens before
                         * changing nr or ns so triggers a retransmit
                         */
                        irlap_wait_min_turn_around(self, &self->qos_tx);
                        irlap_send_rr_frame(self, CMD_FRAME);
                        /* Keep state */
                        break;
                }
                /* FIXME: must check for remote_busy below */
#ifdef CONFIG_IRDA_FAST_RR
                /*
                 *  Reset the fast_RR so we can use the fast RR code with
                 *  full speed the next time since peer may have more frames
                 *  to transmitt
                 */
                self->fast_RR = FALSE;
#endif /* CONFIG_IRDA_FAST_RR */
                IRDA_ASSERT( info != NULL, return -1;);

                ns_status = irlap_validate_ns_received(self, info->ns);
                nr_status = irlap_validate_nr_received(self, info->nr);

                /*
                 *  Check for expected I(nformation) frame
                 */
                if ((ns_status == NS_EXPECTED) && (nr_status == NR_EXPECTED)) {

                        /* Update Vr (next frame for us to receive) */
                        self->vr = (self->vr + 1) % 8;

                        /* Update Nr received, cleanup our retry queue */
                        irlap_update_nr_received(self, info->nr);

                        /*
                         *  Got expected NR, so reset the
                         *  retry_count. This is not done by IrLAP spec,
                         *  which is strange!
                         */
                        self->retry_count = 0;
                        self->ack_required = TRUE;

                        /*  poll bit cleared?  */
                        if (!info->pf) {
                                /* Keep state, do not move this line */
                                irlap_next_state(self, LAP_NRM_P);

                                irlap_data_indication(self, skb, FALSE);
                        } else {
                                /* No longer waiting for pf */
                                del_timer(&self->final_timer);

                                irlap_wait_min_turn_around(self, &self->qos_tx);

                                /* Call higher layer *before* changing state
                                 * to give them a chance to send data in the
                                 * next LAP frame.
                                 * Jean II */
                                irlap_data_indication(self, skb, FALSE);

                                /* XMIT states are the most dangerous state
                                 * to be in, because user requests are
                                 * processed directly and may change state.
                                 * On the other hand, in NDM_P, those
                                 * requests are queued and we will process
                                 * them when we return to irlap_do_event().
                                 * Jean II
                                 */
                                irlap_next_state(self, LAP_XMIT_P);

                                /* This is the last frame.
                                 * Make sure it's always called in XMIT state.
                                 * - Jean II */
                                irlap_start_poll_timer(self, self->poll_timeout);
                        }
                        break;

                }
                /* Unexpected next to send (Ns) */
                if ((ns_status == NS_UNEXPECTED) && (nr_status == NR_EXPECTED))
                {
                        if (!info->pf) {
                                irlap_update_nr_received(self, info->nr);

                                /*
                                 *  Wait until the last frame before doing
                                 *  anything
                                 */

                                /* Keep state */
                                irlap_next_state(self, LAP_NRM_P);
                        } else {
                                IRDA_DEBUG(4,
                                       "%s(), missing or duplicate frame!\n",
                                           __func__);

                                /* Update Nr received */
                                irlap_update_nr_received(self, info->nr);

                                irlap_wait_min_turn_around(self, &self->qos_tx);
                                irlap_send_rr_frame(self, CMD_FRAME);

                                self->ack_required = FALSE;

                                irlap_start_final_timer(self, self->final_timeout);
                                irlap_next_state(self, LAP_NRM_P);
                        }
                        break;
                }
                /*
                 *  Unexpected next to receive (Nr)
                 */
                if ((ns_status == NS_EXPECTED) && (nr_status == NR_UNEXPECTED))
                {
                        if (info->pf) {
                                self->vr = (self->vr + 1) % 8;

                                /* Update Nr received */
                                irlap_update_nr_received(self, info->nr);

                                /* Resend rejected frames */
                                irlap_resend_rejected_frames(self, CMD_FRAME);

                                self->ack_required = FALSE;

                                /* Make sure we account for the time
                                 * to transmit our frames. See comemnts
                                 * in irlap_send_data_primary_poll().
                                 * Jean II */
                                irlap_start_final_timer(self, 2 * self->final_timeout);

                                /* Keep state, do not move this line */
                                irlap_next_state(self, LAP_NRM_P);

                                irlap_data_indication(self, skb, FALSE);
                        } else {
                                /*
                                 *  Do not resend frames until the last
                                 *  frame has arrived from the other
                                 *  device. This is not documented in
                                 *  IrLAP!!
                                 */
                                self->vr = (self->vr + 1) % 8;

                                /* Update Nr received */
                                irlap_update_nr_received(self, info->nr);

                                self->ack_required = FALSE;

                                /* Keep state, do not move this line!*/
                                irlap_next_state(self, LAP_NRM_P);

                                irlap_data_indication(self, skb, FALSE);
                        }
                        break;
                }
                /*
                 *  Unexpected next to send (Ns) and next to receive (Nr)
                 *  Not documented by IrLAP!
                 */
                if ((ns_status == NS_UNEXPECTED) &&
                    (nr_status == NR_UNEXPECTED))
                {
                        IRDA_DEBUG(4, "%s(), unexpected nr and ns!\n",
                                   __func__);
                        if (info->pf) {
                                /* Resend rejected frames */
                                irlap_resend_rejected_frames(self, CMD_FRAME);

                                /* Give peer some time to retransmit!
                                 * But account for our own Tx. */
                                irlap_start_final_timer(self, 2 * self->final_timeout);

                                /* Keep state, do not move this line */
                                irlap_next_state(self, LAP_NRM_P);
                        } else {
                                /* Update Nr received */
                                /* irlap_update_nr_received( info->nr); */

                                self->ack_required = FALSE;
                        }
                        break;
                }

                /*
                 *  Invalid NR or NS
                 */
                if ((nr_status == NR_INVALID) || (ns_status == NS_INVALID)) {
                        if (info->pf) {
                                del_timer(&self->final_timer);

                                irlap_next_state(self, LAP_RESET_WAIT);

                                irlap_disconnect_indication(self, LAP_RESET_INDICATION);
                                self->xmitflag = TRUE;
                        } else {
                                del_timer(&self->final_timer);

                                irlap_disconnect_indication(self, LAP_RESET_INDICATION);

                                self->xmitflag = FALSE;
                        }
                        break;
                }
                IRDA_DEBUG(1, "%s(), Not implemented!\n", __func__);
                IRDA_DEBUG(1, "%s(), event=%s, ns_status=%d, nr_status=%d\n",
                       __func__, irlap_event[event], ns_status, nr_status);
                break;
        case RECV_UI_FRAME:
                /* Poll bit cleared? */
                if (!info->pf) {
                        irlap_data_indication(self, skb, TRUE);
                        irlap_next_state(self, LAP_NRM_P);
                } else {
                        del_timer(&self->final_timer);
                        irlap_data_indication(self, skb, TRUE);
                        irlap_next_state(self, LAP_XMIT_P);
                        IRDA_DEBUG(1, "%s: RECV_UI_FRAME: next state %s\n", __func__, irlap_state[self->state]);
                        irlap_start_poll_timer(self, self->poll_timeout);
                }
                break;
        case RECV_RR_RSP:
                /*
                 *  If you get a RR, the remote isn't busy anymore,
                 *  no matter what the NR
                 */
                self->remote_busy = FALSE;

                /* Stop final timer */
                del_timer(&self->final_timer);

                /*
                 *  Nr as expected?
                 */
                ret = irlap_validate_nr_received(self, info->nr);
                if (ret == NR_EXPECTED) {
                        /* Update Nr received */
                        irlap_update_nr_received(self, info->nr);

                        /*
                         *  Got expected NR, so reset the retry_count. This
                         *  is not done by the IrLAP standard , which is
                         *  strange! DB.
                         */
                        self->retry_count = 0;
                        irlap_wait_min_turn_around(self, &self->qos_tx);

                        irlap_next_state(self, LAP_XMIT_P);

                        /* Start poll timer */
                        irlap_start_poll_timer(self, self->poll_timeout);
                } else if (ret == NR_UNEXPECTED) {
                        IRDA_ASSERT(info != NULL, return -1;);
                        /*
                         *  Unexpected nr!
                         */

                        /* Update Nr received */
                        irlap_update_nr_received(self, info->nr);

                        IRDA_DEBUG(4, "RECV_RR_FRAME: Retrans:%d, nr=%d, va=%d, "
                              "vs=%d, vr=%d\n",
                              self->retry_count, info->nr, self->va,
                              self->vs, self->vr);

                        /* Resend rejected frames */
                        irlap_resend_rejected_frames(self, CMD_FRAME);
                        irlap_start_final_timer(self, self->final_timeout * 2);

                        irlap_next_state(self, LAP_NRM_P);
                } else if (ret == NR_INVALID) {
                        IRDA_DEBUG(1, "%s(), Received RR with "
                                   "invalid nr !\n", __func__);

                        irlap_next_state(self, LAP_RESET_WAIT);

                        irlap_disconnect_indication(self, LAP_RESET_INDICATION);
                        self->xmitflag = TRUE;
                }
                break;
        case RECV_RNR_RSP:
                IRDA_ASSERT(info != NULL, return -1;);

                /* Stop final timer */
                del_timer(&self->final_timer);
                self->remote_busy = TRUE;

                /* Update Nr received */
                irlap_update_nr_received(self, info->nr);
                irlap_next_state(self, LAP_XMIT_P);

                /* Start poll timer */
                irlap_start_poll_timer(self, self->poll_timeout);
                break;
        case RECV_FRMR_RSP:
                del_timer(&self->final_timer);
                self->xmitflag = TRUE;
                irlap_next_state(self, LAP_RESET_WAIT);
                irlap_reset_indication(self);
                break;
        case FINAL_TIMER_EXPIRED:
                /*
                 *  We are allowed to wait for additional 300 ms if
                 *  final timer expires when we are in the middle
                 *  of receiving a frame (page 45, IrLAP). Check that
                 *  we only do this once for each frame.
                 */
                if (irda_device_is_receiving(self->netdev) && !self->add_wait) {
                        IRDA_DEBUG(1, "FINAL_TIMER_EXPIRED when receiving a "
                              "frame! Waiting a little bit more!\n");
                        irlap_start_final_timer(self, msecs_to_jiffies(300));

                        /*
                         *  Don't allow this to happen one more time in a row,
                         *  or else we can get a pretty tight loop here if
                         *  if we only receive half a frame. DB.
                         */
                        self->add_wait = TRUE;
                        break;
                }
                self->add_wait = FALSE;

                /* N2 is the disconnect timer. Until we reach it, we retry */
                if (self->retry_count < self->N2) {
                        if (skb_peek(&self->wx_list) == NULL) {
                                /* Retry sending the pf bit to the secondary */
                                IRDA_DEBUG(4, "nrm_p: resending rr");
                                irlap_wait_min_turn_around(self, &self->qos_tx);
                                irlap_send_rr_frame(self, CMD_FRAME);
                        } else {
                                IRDA_DEBUG(4, "nrm_p: resend frames");
                                irlap_resend_rejected_frames(self, CMD_FRAME);
                        }

                        irlap_start_final_timer(self, self->final_timeout);
                        self->retry_count++;
                        IRDA_DEBUG(4, "irlap_state_nrm_p: FINAL_TIMER_EXPIRED:"
                                   " retry_count=%d\n", self->retry_count);

                        /* Early warning event. I'm using a pretty liberal
                         * interpretation of the spec and generate an event
                         * every time the timer is multiple of N1 (and not
                         * only the first time). This allow application
                         * to know precisely if connectivity restart...
                         * Jean II */
                        if((self->retry_count % self->N1) == 0)
                                irlap_status_indication(self,
                                                        STATUS_NO_ACTIVITY);

                        /* Keep state */
                } else {
                        irlap_apply_default_connection_parameters(self);

                        /* Always switch state before calling upper layers */
                        irlap_next_state(self, LAP_NDM);
                        irlap_disconnect_indication(self, LAP_NO_RESPONSE);
                }
                break;
        case RECV_REJ_RSP:
                irlap_update_nr_received(self, info->nr);
                if (self->remote_busy) {
                        irlap_wait_min_turn_around(self, &self->qos_tx);
                        irlap_send_rr_frame(self, CMD_FRAME);
                } else
                        irlap_resend_rejected_frames(self, CMD_FRAME);
                irlap_start_final_timer(self, 2 * self->final_timeout);
                break;
        case RECV_SREJ_RSP:
                irlap_update_nr_received(self, info->nr);
                if (self->remote_busy) {
                        irlap_wait_min_turn_around(self, &self->qos_tx);
                        irlap_send_rr_frame(self, CMD_FRAME);
                } else
                        irlap_resend_rejected_frame(self, CMD_FRAME);
                irlap_start_final_timer(self, 2 * self->final_timeout);
                break;
        case RECV_RD_RSP:
                IRDA_DEBUG(1, "%s(), RECV_RD_RSP\n", __func__);

                irlap_flush_all_queues(self);
                irlap_next_state(self, LAP_XMIT_P);
                /* Call back the LAP state machine to do a proper disconnect */
                irlap_disconnect_request(self);
                break;
        default:
                IRDA_DEBUG(1, "%s(), Unknown event %s\n",
                            __func__, irlap_event[event]);

                ret = -1;
                break;
        }
        return ret;
}

/*
 * Function irlap_state_reset_wait (event, skb, info)
 *
 *    We have informed the service user of a reset condition, and is
 *    awaiting reset of disconnect request.
 *
 */
static int irlap_state_reset_wait(struct irlap_cb *self, IRLAP_EVENT event,
                                  struct sk_buff *skb, struct irlap_info *info)
{
        int ret = 0;

        IRDA_DEBUG(3, "%s(), event = %s\n", __func__, irlap_event[event]);

        IRDA_ASSERT(self != NULL, return -1;);
        IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);

        switch (event) {
        case RESET_REQUEST:
                if (self->xmitflag) {
                        irlap_wait_min_turn_around(self, &self->qos_tx);
                        irlap_send_snrm_frame(self, NULL);
                        irlap_start_final_timer(self, self->final_timeout);
                        irlap_next_state(self, LAP_RESET);
                } else {
                        irlap_start_final_timer(self, self->final_timeout);
                        irlap_next_state(self, LAP_RESET);
                }
                break;
        case DISCONNECT_REQUEST:
                irlap_wait_min_turn_around( self, &self->qos_tx);
                irlap_send_disc_frame( self);
                irlap_flush_all_queues( self);
                irlap_start_final_timer( self, self->final_timeout);
                self->retry_count = 0;
                irlap_next_state( self, LAP_PCLOSE);
                break;
        default:
                IRDA_DEBUG(2, "%s(), Unknown event %s\n", __func__,
                           irlap_event[event]);

                ret = -1;
                break;
        }
        return ret;
}

/*
 * Function irlap_state_reset (self, event, skb, info)
 *
 *    We have sent a SNRM reset command to the peer layer, and is awaiting
 *    reply.
 *
 */
static int irlap_state_reset(struct irlap_cb *self, IRLAP_EVENT event,
                             struct sk_buff *skb, struct irlap_info *info)
{
        int ret = 0;

        IRDA_DEBUG(3, "%s(), event = %s\n", __func__, irlap_event[event]);

        IRDA_ASSERT(self != NULL, return -1;);
        IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);

        switch (event) {
        case RECV_DISC_CMD:
                del_timer(&self->final_timer);

                irlap_apply_default_connection_parameters(self);

                /* Always switch state before calling upper layers */
                irlap_next_state(self, LAP_NDM);

                irlap_disconnect_indication(self, LAP_NO_RESPONSE);

                break;
        case RECV_UA_RSP:
                del_timer(&self->final_timer);

                /* Initiate connection state */
                irlap_initiate_connection_state(self);

                irlap_reset_confirm();

                self->remote_busy = FALSE;

                irlap_next_state(self, LAP_XMIT_P);

                irlap_start_poll_timer(self, self->poll_timeout);

                break;
        case FINAL_TIMER_EXPIRED:
                if (self->retry_count < 3) {
                        irlap_wait_min_turn_around(self, &self->qos_tx);

                        IRDA_ASSERT(self->netdev != NULL, return -1;);
                        irlap_send_snrm_frame(self, self->qos_dev);

                        self->retry_count++; /* Experimental!! */

                        irlap_start_final_timer(self, self->final_timeout);
                        irlap_next_state(self, LAP_RESET);
                } else if (self->retry_count >= self->N3) {
                        irlap_apply_default_connection_parameters(self);

                        /* Always switch state before calling upper layers */
                        irlap_next_state(self, LAP_NDM);

                        irlap_disconnect_indication(self, LAP_NO_RESPONSE);
                }
                break;
        case RECV_SNRM_CMD:
                /*
                 * SNRM frame is not allowed to contain an I-field in this
                 * state
                 */
                if (!info) {
                        IRDA_DEBUG(3, "%s(), RECV_SNRM_CMD\n", __func__);
                        irlap_initiate_connection_state(self);
                        irlap_wait_min_turn_around(self, &self->qos_tx);
                        irlap_send_ua_response_frame(self, &self->qos_rx);
                        irlap_reset_confirm();
                        irlap_start_wd_timer(self, self->wd_timeout);
                        irlap_next_state(self, LAP_NDM);
                } else {
                        IRDA_DEBUG(0,
                                   "%s(), SNRM frame contained an I field!\n",
                                   __func__);
                }
                break;
        default:
                IRDA_DEBUG(1, "%s(), Unknown event %s\n",
                           __func__, irlap_event[event]);

                ret = -1;
                break;
        }
        return ret;
}

/*
 * Function irlap_state_xmit_s (event, skb, info)
 *
 *   XMIT_S, The secondary station has been given the right to transmit,
 *   and we therefor do not expect to receive any transmissions from other
 *   stations.
 */
static int irlap_state_xmit_s(struct irlap_cb *self, IRLAP_EVENT event,
                              struct sk_buff *skb, struct irlap_info *info)
{
        int ret = 0;

        IRDA_DEBUG(4, "%s(), event=%s\n", __func__, irlap_event[event]);

        IRDA_ASSERT(self != NULL, return -ENODEV;);
        IRDA_ASSERT(self->magic == LAP_MAGIC, return -EBADR;);

        switch (event) {
        case SEND_I_CMD:
                /*
                 *  Send frame only if send window > 0
                 */
                if ((self->window > 0) && (!self->remote_busy)) {
                        int nextfit;
#ifdef CONFIG_IRDA_DYNAMIC_WINDOW
                        struct sk_buff *skb_next;

                        /*
                         * Same deal as in irlap_state_xmit_p(), so see
                         * the comments at that point.
                         * We are the secondary, so there are only subtle
                         * differences. - Jean II
                         */

                        /* Check if a subsequent skb exist and would fit in
                         * the current window (with respect to turnaround
                         * time). - Jean II */
                        skb_next = skb_peek(&self->txq);
                        nextfit = ((skb_next != NULL) &&
                                   ((skb_next->len + skb->len) <=
                                    self->bytes_left));

                        /*
                         *  Test if we have transmitted more bytes over the
                         *  link than its possible to do with the current
                         *  speed and turn-around-time.
                         */
                        if((!nextfit) && (skb->len > self->bytes_left)) {
                                IRDA_DEBUG(0, "%s(), Not allowed to transmit"
                                           " more bytes!\n", __func__);
                                /* Requeue the skb */
                                skb_queue_head(&self->txq, skb_get(skb));

                                /*
                                 *  Switch to NRM_S, this is only possible
                                 *  when we are in secondary mode, since we
                                 *  must be sure that we don't miss any RR
                                 *  frames
                                 */
                                self->window = self->window_size;
                                self->bytes_left = self->line_capacity;
                                irlap_start_wd_timer(self, self->wd_timeout);

                                irlap_next_state(self, LAP_NRM_S);
                                /* Slight difference with primary :
                                 * here we would wait for the other side to
                                 * expire the turnaround. - Jean II */

                                return -EPROTO; /* Try again later */
                        }
                        /* Substract space used by this skb */
                        self->bytes_left -= skb->len;
#else   /* CONFIG_IRDA_DYNAMIC_WINDOW */
                        /* Window has been adjusted for the max packet
                         * size, so much simpler... - Jean II */
                        nextfit = !skb_queue_empty(&self->txq);
#endif /* CONFIG_IRDA_DYNAMIC_WINDOW */
                        /*
                         *  Send data with final bit cleared only if window > 1
                         *  and there is more frames to be sent
                         */
                        if ((self->window > 1) && (nextfit)) {
                                irlap_send_data_secondary(self, skb);
                                irlap_next_state(self, LAP_XMIT_S);
                        } else {
                                irlap_send_data_secondary_final(self, skb);
                                irlap_next_state(self, LAP_NRM_S);

                                /*
                                 * Make sure state machine does not try to send
                                 * any more frames
                                 */
                                ret = -EPROTO;
                        }
                } else {
                        IRDA_DEBUG(2, "%s(), Unable to send!\n", __func__);
                        skb_queue_head(&self->txq, skb_get(skb));
                        ret = -EPROTO;
                }
                break;
        case DISCONNECT_REQUEST:
                irlap_send_rd_frame(self);
                irlap_flush_all_queues(self);
                irlap_start_wd_timer(self, self->wd_timeout);
                irlap_next_state(self, LAP_SCLOSE);
                break;
        case DATA_REQUEST:
                /* Nothing to do, irlap_do_event() will send the packet
                 * when we return... - Jean II */
                break;
        default:
                IRDA_DEBUG(2, "%s(), Unknown event %s\n", __func__,
                           irlap_event[event]);

                ret = -EINVAL;
                break;
        }
        return ret;
}

/*
 * Function irlap_state_nrm_s (event, skb, info)
 *
 *    NRM_S (Normal Response Mode as Secondary) state, in this state we are
 *    expecting to receive frames from the primary station
 *
 */
static int irlap_state_nrm_s(struct irlap_cb *self, IRLAP_EVENT event,
                             struct sk_buff *skb, struct irlap_info *info)
{
        int ns_status;
        int nr_status;
        int ret = 0;

        IRDA_DEBUG(4, "%s(), event=%s\n", __func__, irlap_event[ event]);

        IRDA_ASSERT(self != NULL, return -1;);
        IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);

        switch (event) {
        case RECV_I_CMD: /* Optimize for the common case */
                /* FIXME: must check for remote_busy below */
                IRDA_DEBUG(4, "%s(), event=%s nr=%d, vs=%d, ns=%d, "
                           "vr=%d, pf=%d\n", __func__,
                           irlap_event[event], info->nr,
                           self->vs, info->ns, self->vr, info->pf);

                self->retry_count = 0;

                ns_status = irlap_validate_ns_received(self, info->ns);
                nr_status = irlap_validate_nr_received(self, info->nr);
                /*
                 *  Check for expected I(nformation) frame
                 */
                if ((ns_status == NS_EXPECTED) && (nr_status == NR_EXPECTED)) {

                        /* Update Vr (next frame for us to receive) */
                        self->vr = (self->vr + 1) % 8;

                        /* Update Nr received */
                        irlap_update_nr_received(self, info->nr);

                        /*
                         *  poll bit cleared?
                         */
                        if (!info->pf) {

                                self->ack_required = TRUE;

                                /*
                                 *  Starting WD-timer here is optional, but
                                 *  not recommended. Note 6 IrLAP p. 83
                                 */
#if 0
                                irda_start_timer(WD_TIMER, self->wd_timeout);
#endif
                                /* Keep state, do not move this line */
                                irlap_next_state(self, LAP_NRM_S);

                                irlap_data_indication(self, skb, FALSE);
                                break;
                        } else {
                                /*
                                 *  We should wait before sending RR, and
                                 *  also before changing to XMIT_S
                                 *  state. (note 1, IrLAP p. 82)
                                 */
                                irlap_wait_min_turn_around(self, &self->qos_tx);

                                /*
                                 * Give higher layers a chance to
                                 * immediately reply with some data before
                                 * we decide if we should send a RR frame
                                 * or not
                                 */
                                irlap_data_indication(self, skb, FALSE);

                                /* Any pending data requests?  */
                                if (!skb_queue_empty(&self->txq) &&
                                    (self->window > 0))
                                {
                                        self->ack_required = TRUE;

                                        del_timer(&self->wd_timer);

                                        irlap_next_state(self, LAP_XMIT_S);
                                } else {
                                        irlap_send_rr_frame(self, RSP_FRAME);
                                        irlap_start_wd_timer(self,
                                                             self->wd_timeout);

                                        /* Keep the state */
                                        irlap_next_state(self, LAP_NRM_S);
                                }
                                break;
                        }
                }
                /*
                 *  Check for Unexpected next to send (Ns)
                 */
                if ((ns_status == NS_UNEXPECTED) && (nr_status == NR_EXPECTED))
                {
                        /* Unexpected next to send, with final bit cleared */
                        if (!info->pf) {
                                irlap_update_nr_received(self, info->nr);

                                irlap_start_wd_timer(self, self->wd_timeout);
                        } else {
                                /* Update Nr received */
                                irlap_update_nr_received(self, info->nr);

                                irlap_wait_min_turn_around(self, &self->qos_tx);
                                irlap_send_rr_frame(self, RSP_FRAME);

                                irlap_start_wd_timer(self, self->wd_timeout);
                        }
                        break;
                }

                /*
                 *  Unexpected Next to Receive(NR) ?
                 */
                if ((ns_status == NS_EXPECTED) && (nr_status == NR_UNEXPECTED))
                {
                        if (info->pf) {
                                IRDA_DEBUG(4, "RECV_I_RSP: frame(s) lost\n");

                                self->vr = (self->vr + 1) % 8;

                                /* Update Nr received */
                                irlap_update_nr_received(self, info->nr);

                                /* Resend rejected frames */
                                irlap_resend_rejected_frames(self, RSP_FRAME);

                                /* Keep state, do not move this line */
                                irlap_next_state(self, LAP_NRM_S);

                                irlap_data_indication(self, skb, FALSE);
                                irlap_start_wd_timer(self, self->wd_timeout);
                                break;
                        }
                        /*
                         *  This is not documented in IrLAP!! Unexpected NR
                         *  with poll bit cleared
                         */
                        if (!info->pf) {
                                self->vr = (self->vr + 1) % 8;

                                /* Update Nr received */
                                irlap_update_nr_received(self, info->nr);

                                /* Keep state, do not move this line */
                                irlap_next_state(self, LAP_NRM_S);

                                irlap_data_indication(self, skb, FALSE);
                                irlap_start_wd_timer(self, self->wd_timeout);
                        }
                        break;
                }

                if (ret == NR_INVALID) {
                        IRDA_DEBUG(0, "NRM_S, NR_INVALID not implemented!\n");
                }
                if (ret == NS_INVALID) {
                        IRDA_DEBUG(0, "NRM_S, NS_INVALID not implemented!\n");
                }
                break;
        case RECV_UI_FRAME:
                /*
                 *  poll bit cleared?
                 */
                if (!info->pf) {
                        irlap_data_indication(self, skb, TRUE);
                        irlap_next_state(self, LAP_NRM_S); /* Keep state */
                } else {
                        /*
                         *  Any pending data requests?
                         */
                        if (!skb_queue_empty(&self->txq) &&
                            (self->window > 0) && !self->remote_busy)
                        {
                                irlap_data_indication(self, skb, TRUE);

                                del_timer(&self->wd_timer);

                                irlap_next_state(self, LAP_XMIT_S);
                        } else {
                                irlap_data_indication(self, skb, TRUE);

                                irlap_wait_min_turn_around(self, &self->qos_tx);

                                irlap_send_rr_frame(self, RSP_FRAME);
                                self->ack_required = FALSE;

                                irlap_start_wd_timer(self, self->wd_timeout);

                                /* Keep the state */
                                irlap_next_state(self, LAP_NRM_S);
                        }
                }
                break;
        case RECV_RR_CMD:
                self->retry_count = 0;

                /*
                 *  Nr as expected?
                 */
                nr_status = irlap_validate_nr_received(self, info->nr);
                if (nr_status == NR_EXPECTED) {
                        if (!skb_queue_empty(&self->txq) &&
                            (self->window > 0)) {
                                self->remote_busy = FALSE;

                                /* Update Nr received */
                                irlap_update_nr_received(self, info->nr);
                                del_timer(&self->wd_timer);

                                irlap_wait_min_turn_around(self, &self->qos_tx);
                                irlap_next_state(self, LAP_XMIT_S);
                        } else {
                                self->remote_busy = FALSE;
                                /* Update Nr received */
                                irlap_update_nr_received(self, info->nr);
                                irlap_wait_min_turn_around(self, &self->qos_tx);
                                irlap_start_wd_timer(self, self->wd_timeout);

                                /* Note : if the link is idle (this case),
                                 * we never go in XMIT_S, so we never get a
                                 * chance to process any DISCONNECT_REQUEST.
                                 * Do it now ! - Jean II */
                                if (self->disconnect_pending) {
                                        /* Disconnect */
                                        irlap_send_rd_frame(self);
                                        irlap_flush_all_queues(self);

                                        irlap_next_state(self, LAP_SCLOSE);
                                } else {
                                        /* Just send back pf bit */
                                        irlap_send_rr_frame(self, RSP_FRAME);

                                        irlap_next_state(self, LAP_NRM_S);
                                }
                        }
                } else if (nr_status == NR_UNEXPECTED) {
                        self->remote_busy = FALSE;
                        irlap_update_nr_received(self, info->nr);
                        irlap_resend_rejected_frames(self, RSP_FRAME);

                        irlap_start_wd_timer(self, self->wd_timeout);

                        /* Keep state */
                        irlap_next_state(self, LAP_NRM_S);
                } else {
                        IRDA_DEBUG(1, "%s(), invalid nr not implemented!\n",
                                   __func__);
                }
                break;
        case RECV_SNRM_CMD:
                /* SNRM frame is not allowed to contain an I-field */
                if (!info) {
                        del_timer(&self->wd_timer);
                        IRDA_DEBUG(1, "%s(), received SNRM cmd\n", __func__);
                        irlap_next_state(self, LAP_RESET_CHECK);

                        irlap_reset_indication(self);
                } else {
                        IRDA_DEBUG(0,
                                   "%s(), SNRM frame contained an I-field!\n",
                                   __func__);

                }
                break;
        case RECV_REJ_CMD:
                irlap_update_nr_received(self, info->nr);
                if (self->remote_busy) {
                        irlap_wait_min_turn_around(self, &self->qos_tx);
                        irlap_send_rr_frame(self, RSP_FRAME);
                } else
                        irlap_resend_rejected_frames(self, RSP_FRAME);
                irlap_start_wd_timer(self, self->wd_timeout);
                break;
        case RECV_SREJ_CMD:
                irlap_update_nr_received(self, info->nr);
                if (self->remote_busy) {
                        irlap_wait_min_turn_around(self, &self->qos_tx);
                        irlap_send_rr_frame(self, RSP_FRAME);
                } else
                        irlap_resend_rejected_frame(self, RSP_FRAME);
                irlap_start_wd_timer(self, self->wd_timeout);
                break;
        case WD_TIMER_EXPIRED:
                /*
                 *  Wait until retry_count * n matches negotiated threshold/
                 *  disconnect time (note 2 in IrLAP p. 82)
                 *
                 * Similar to irlap_state_nrm_p() -> FINAL_TIMER_EXPIRED
                 * Note : self->wd_timeout = (self->final_timeout * 2),
                 *   which explain why we use (self->N2 / 2) here !!!
                 * Jean II
                 */
                IRDA_DEBUG(1, "%s(), retry_count = %d\n", __func__,
                           self->retry_count);

                if (self->retry_count < (self->N2 / 2)) {
                        /* No retry, just wait for primary */
                        irlap_start_wd_timer(self, self->wd_timeout);
                        self->retry_count++;

                        if((self->retry_count % (self->N1 / 2)) == 0)
                                irlap_status_indication(self,
                                                        STATUS_NO_ACTIVITY);
                } else {
                        irlap_apply_default_connection_parameters(self);

                        /* Always switch state before calling upper layers */
                        irlap_next_state(self, LAP_NDM);
                        irlap_disconnect_indication(self, LAP_NO_RESPONSE);
                }
                break;
        case RECV_DISC_CMD:
                /* Always switch state before calling upper layers */
                irlap_next_state(self, LAP_NDM);

                /* Send disconnect response */
                irlap_wait_min_turn_around(self, &self->qos_tx);
                irlap_send_ua_response_frame(self, NULL);

                del_timer(&self->wd_timer);
                irlap_flush_all_queues(self);
                /* Set default link parameters */
                irlap_apply_default_connection_parameters(self);

                irlap_disconnect_indication(self, LAP_DISC_INDICATION);
                break;
        case RECV_DISCOVERY_XID_CMD:
                irlap_wait_min_turn_around(self, &self->qos_tx);
                irlap_send_rr_frame(self, RSP_FRAME);
                self->ack_required = TRUE;
                irlap_start_wd_timer(self, self->wd_timeout);
                irlap_next_state(self, LAP_NRM_S);

                break;
        case RECV_TEST_CMD:
                /* Remove test frame header (only LAP header in NRM) */
                skb_pull(skb, LAP_ADDR_HEADER + LAP_CTRL_HEADER);

                irlap_wait_min_turn_around(self, &self->qos_tx);
                irlap_start_wd_timer(self, self->wd_timeout);

                /* Send response (info will be copied) */
                irlap_send_test_frame(self, self->caddr, info->daddr, skb);
                break;
        default:
                IRDA_DEBUG(1, "%s(), Unknown event %d, (%s)\n", __func__,
                           event, irlap_event[event]);

                ret = -EINVAL;
                break;
        }
        return ret;
}

/*
 * Function irlap_state_sclose (self, event, skb, info)
 */
static int irlap_state_sclose(struct irlap_cb *self, IRLAP_EVENT event,
                              struct sk_buff *skb, struct irlap_info *info)
{
        int ret = 0;

        IRDA_DEBUG(1, "%s()\n", __func__);

        IRDA_ASSERT(self != NULL, return -ENODEV;);
        IRDA_ASSERT(self->magic == LAP_MAGIC, return -EBADR;);

        switch (event) {
        case RECV_DISC_CMD:
                /* Always switch state before calling upper layers */
                irlap_next_state(self, LAP_NDM);

                /* Send disconnect response */
                irlap_wait_min_turn_around(self, &self->qos_tx);
                irlap_send_ua_response_frame(self, NULL);

                del_timer(&self->wd_timer);
                /* Set default link parameters */
                irlap_apply_default_connection_parameters(self);

                irlap_disconnect_indication(self, LAP_DISC_INDICATION);
                break;
        case RECV_DM_RSP:
                /* IrLAP-1.1 p.82: in SCLOSE, S and I type RSP frames
                 * shall take us down into default NDM state, like DM_RSP
                 */
        case RECV_RR_RSP:
        case RECV_RNR_RSP:
        case RECV_REJ_RSP:
        case RECV_SREJ_RSP:
        case RECV_I_RSP:
                /* Always switch state before calling upper layers */
                irlap_next_state(self, LAP_NDM);

                del_timer(&self->wd_timer);
                irlap_apply_default_connection_parameters(self);

                irlap_disconnect_indication(self, LAP_DISC_INDICATION);
                break;
        case WD_TIMER_EXPIRED:
                /* Always switch state before calling upper layers */
                irlap_next_state(self, LAP_NDM);

                irlap_apply_default_connection_parameters(self);

                irlap_disconnect_indication(self, LAP_DISC_INDICATION);
                break;
        default:
                /* IrLAP-1.1 p.82: in SCLOSE, basically any received frame
                 * with pf=1 shall restart the wd-timer and resend the rd:rsp
                 */
                if (info != NULL  &&  info->pf) {
                        del_timer(&self->wd_timer);
                        irlap_wait_min_turn_around(self, &self->qos_tx);
                        irlap_send_rd_frame(self);
                        irlap_start_wd_timer(self, self->wd_timeout);
                        break;          /* stay in SCLOSE */
                }

                IRDA_DEBUG(1, "%s(), Unknown event %d, (%s)\n", __func__,
                           event, irlap_event[event]);

                ret = -EINVAL;
                break;
        }

        return -1;
}

static int irlap_state_reset_check( struct irlap_cb *self, IRLAP_EVENT event,
                                   struct sk_buff *skb,
                                   struct irlap_info *info)
{
        int ret = 0;

        IRDA_DEBUG(1, "%s(), event=%s\n", __func__, irlap_event[event]);

        IRDA_ASSERT(self != NULL, return -ENODEV;);
        IRDA_ASSERT(self->magic == LAP_MAGIC, return -EBADR;);

        switch (event) {
        case RESET_RESPONSE:
                irlap_send_ua_response_frame(self, &self->qos_rx);
                irlap_initiate_connection_state(self);
                irlap_start_wd_timer(self, WD_TIMEOUT);
                irlap_flush_all_queues(self);

                irlap_next_state(self, LAP_NRM_S);
                break;
        case DISCONNECT_REQUEST:
                irlap_wait_min_turn_around(self, &self->qos_tx);
                irlap_send_rd_frame(self);
                irlap_start_wd_timer(self, WD_TIMEOUT);
                irlap_next_state(self, LAP_SCLOSE);
                break;
        default:
                IRDA_DEBUG(1, "%s(), Unknown event %d, (%s)\n", __func__,
                           event, irlap_event[event]);

                ret = -EINVAL;
                break;
        }
        return ret;
}