include/net/irda/irlap.h

   1 /*********************************************************************
   2  *
   3  * Filename:      irlap.h
   4  * Version:       0.8
   5  * Description:   An IrDA LAP driver for Linux
   6  * Status:        Experimental.
   7  * Author:        Dag Brattli <dagb@cs.uit.no>
   8  * Created at:    Mon Aug  4 20:40:53 1997
   9  * Modified at:   Fri Dec 10 13:21:17 1999
  10  * Modified by:   Dag Brattli <dagb@cs.uit.no>
  11  *
  12  *     Copyright (c) 1998-1999 Dag Brattli <dagb@cs.uit.no>,
  13  *     All Rights Reserved.
  14  *     Copyright (c) 2000-2002 Jean Tourrilhes <jt@hpl.hp.com>
  15  *
  16  *     This program is free software; you can redistribute it and/or
  17  *     modify it under the terms of the GNU General Public License as
  18  *     published by the Free Software Foundation; either version 2 of
  19  *     the License, or (at your option) any later version.
  20  *
  21  *     Neither Dag Brattli nor University of Tromsø admit liability nor
  22  *     provide warranty for any of this software. This material is
  23  *     provided "AS-IS" and at no charge.
  24  *
  25  ********************************************************************/
  26
  27 #ifndef IRLAP_H
  28 #define IRLAP_H
  29
  30 #include <linux/types.h>
  31 #include <linux/skbuff.h>
  32 #include <linux/netdevice.h>
  33 #include <linux/timer.h>
  34
  35 #include <net/irda/irqueue.h>           /* irda_queue_t */
  36 #include <net/irda/qos.h>               /* struct qos_info */
  37 #include <net/irda/discovery.h>         /* discovery_t */
  38 #include <net/irda/irlap_event.h>       /* IRLAP_STATE, ... */
  39 #include <net/irda/irmod.h>             /* struct notify_t */
  40
  41 #define CONFIG_IRDA_DYNAMIC_WINDOW 1
  42
  43 #define LAP_RELIABLE   1
  44 #define LAP_UNRELIABLE 0
  45
  46 #define LAP_ADDR_HEADER 1  /* IrLAP Address Header */
  47 #define LAP_CTRL_HEADER 1  /* IrLAP Control Header */
  48
  49 /* May be different when we get VFIR */
  50 #define LAP_MAX_HEADER (LAP_ADDR_HEADER + LAP_CTRL_HEADER)
  51
  52 /* Each IrDA device gets a random 32 bits IRLAP device address */
  53 #define LAP_ALEN 4
  54
  55 #define BROADCAST  0xffffffff /* Broadcast device address */
  56 #define CBROADCAST 0xfe       /* Connection broadcast address */
  57 #define XID_FORMAT 0x01       /* Discovery XID format */
  58
  59 /* Nobody seems to use this constant. */
  60 #define LAP_WINDOW_SIZE 8
  61 /* We keep the LAP queue very small to minimise the amount of buffering.
  62  * this improve latency and reduce resource consumption.
  63  * This work only because we have synchronous refilling of IrLAP through
  64  * the flow control mechanism (via scheduler and IrTTP).
  65  * 2 buffers is the minimum we can work with, one that we send while polling
  66  * IrTTP, and another to know that we should not send the pf bit.
  67  * Jean II */
  68 #define LAP_HIGH_THRESHOLD     2
  69 /* Some rare non TTP clients don't implement flow control, and
  70  * so don't comply with the above limit (and neither with this one).
  71  * For IAP and management, it doesn't matter, because they never transmit much.
  72  *.For IrLPT, this should be fixed.
  73  * - Jean II */
  74 #define LAP_MAX_QUEUE 10
  75 /* Please note that all IrDA management frames (LMP/TTP conn req/disc and
  76  * IAS queries) fall in the second category and are sent to LAP even if TTP
  77  * is stopped. This means that those frames will wait only a maximum of
  78  * two (2) data frames before beeing sent on the "wire", which speed up
  79  * new socket setup when the link is saturated.
  80  * Same story for two sockets competing for the medium : if one saturates
  81  * the LAP, when the other want to transmit it only has to wait for
  82  * maximum three (3) packets (2 + one scheduling), which improve performance
  83  * of delay sensitive applications.
  84  * Jean II */
  85
  86 #define NR_EXPECTED     1
  87 #define NR_UNEXPECTED   0
  88 #define NR_INVALID     -1
  89
  90 #define NS_EXPECTED     1
  91 #define NS_UNEXPECTED   0
  92 #define NS_INVALID     -1
  93
  94 /*
  95  *  Meta information passed within the IrLAP state machine
  96  */
  97 struct irlap_info {
  98         __u8 caddr;   /* Connection address */
  99         __u8 control; /* Frame type */
 100         __u8 cmd;
 101
 102         __u32 saddr;
 103         __u32 daddr;
 104
 105         int pf;        /* Poll/final bit set */
 106
 107         __u8  nr;      /* Sequence number of next frame expected */
 108         __u8  ns;      /* Sequence number of frame sent */
 109
 110         int  S;        /* Number of slots */
 111         int  slot;     /* Random chosen slot */
 112         int  s;        /* Current slot */
 113
 114         discovery_t *discovery; /* Discovery information */
 115 };
 116
 117 /* Main structure of IrLAP */
 118 struct irlap_cb {
 119         irda_queue_t q;     /* Must be first */
 120         magic_t magic;
 121
 122         /* Device we are attached to */
 123         struct net_device  *netdev;
 124         char            hw_name[2*IFNAMSIZ + 1];
 125
 126         /* Connection state */
 127         volatile IRLAP_STATE state;       /* Current state */
 128
 129         /* Timers used by IrLAP */
 130         struct timer_list query_timer;
 131         struct timer_list slot_timer;
 132         struct timer_list discovery_timer;
 133         struct timer_list final_timer;
 134         struct timer_list poll_timer;
 135         struct timer_list wd_timer;
 136         struct timer_list backoff_timer;
 137
 138         /* Media busy stuff */
 139         struct timer_list media_busy_timer;
 140         int media_busy;
 141
 142         /* Timeouts which will be different with different turn time */
 143         int slot_timeout;
 144         int poll_timeout;
 145         int final_timeout;
 146         int wd_timeout;
 147
 148         struct sk_buff_head txq;  /* Frames to be transmitted */
 149         struct sk_buff_head txq_ultra;
 150
 151         __u8    caddr;        /* Connection address */
 152         __u32   saddr;        /* Source device address */
 153         __u32   daddr;        /* Destination device address */
 154
 155         int     retry_count;  /* Times tried to establish connection */
 156         int     add_wait;     /* True if we are waiting for frame */
 157
 158         __u8    connect_pending;
 159         __u8    disconnect_pending;
 160
 161         /*  To send a faster RR if tx queue empty */
 162 #ifdef CONFIG_IRDA_FAST_RR
 163         int     fast_RR_timeout;
 164         int     fast_RR;
 165 #endif /* CONFIG_IRDA_FAST_RR */
 166
 167         int N1; /* N1 * F-timer = Negitiated link disconnect warning threshold */
 168         int N2; /* N2 * F-timer = Negitiated link disconnect time */
 169         int N3; /* Connection retry count */
 170
 171         int     local_busy;
 172         int     remote_busy;
 173         int     xmitflag;
 174
 175         __u8    vs;            /* Next frame to be sent */
 176         __u8    vr;            /* Next frame to be received */
 177         __u8    va;            /* Last frame acked */
 178         int     window;        /* Nr of I-frames allowed to send */
 179         int     window_size;   /* Current negotiated window size */
 180
 181 #ifdef CONFIG_IRDA_DYNAMIC_WINDOW
 182         __u32   line_capacity; /* Number of bytes allowed to send */
 183         __u32   bytes_left;    /* Number of bytes still allowed to transmit */
 184 #endif /* CONFIG_IRDA_DYNAMIC_WINDOW */
 185
 186         struct sk_buff_head wx_list;
 187
 188         __u8    ack_required;
 189
 190         /* XID parameters */
 191         __u8    S;           /* Number of slots */
 192         __u8    slot;        /* Random chosen slot */
 193         __u8    s;           /* Current slot */
 194         int     frame_sent;  /* Have we sent reply? */
 195
 196         hashbin_t   *discovery_log;
 197         discovery_t *discovery_cmd;
 198
 199         __u32 speed;            /* Link speed */
 200
 201         struct qos_info  qos_tx;   /* QoS requested by peer */
 202         struct qos_info  qos_rx;   /* QoS requested by self */
 203         struct qos_info *qos_dev;  /* QoS supported by device */
 204
 205         notify_t notify; /* Callbacks to IrLMP */
 206
 207         int    mtt_required;  /* Minimum turnaround time required */
 208         int    xbofs_delay;   /* Nr of XBOF's used to MTT */
 209         int    bofs_count;    /* Negotiated extra BOFs */
 210         int    next_bofs;     /* Negotiated extra BOFs after next frame */
 211
 212         int    mode;     /* IrLAP mode (primary, secondary or monitor) */
 213 };
 214
 215 /*
 216  *  Function prototypes
 217  */
 218 int irlap_init(void);
 219 void irlap_cleanup(void);
 220
 221 struct irlap_cb *irlap_open(struct net_device *dev, struct qos_info *qos,
 222                             const char *hw_name);
 223 void irlap_close(struct irlap_cb *self);
 224
 225 void irlap_connect_request(struct irlap_cb *self, __u32 daddr,
 226                            struct qos_info *qos, int sniff);
 227 void irlap_connect_response(struct irlap_cb *self, struct sk_buff *skb);
 228 void irlap_connect_indication(struct irlap_cb *self, struct sk_buff *skb);
 229 void irlap_connect_confirm(struct irlap_cb *, struct sk_buff *skb);
 230
 231 void irlap_data_indication(struct irlap_cb *, struct sk_buff *, int unreliable);
 232 void irlap_data_request(struct irlap_cb *, struct sk_buff *, int unreliable);
 233
 234 #ifdef CONFIG_IRDA_ULTRA
 235 void irlap_unitdata_request(struct irlap_cb *, struct sk_buff *);
 236 void irlap_unitdata_indication(struct irlap_cb *, struct sk_buff *);
 237 #endif /* CONFIG_IRDA_ULTRA */
 238
 239 void irlap_disconnect_request(struct irlap_cb *);
 240 void irlap_disconnect_indication(struct irlap_cb *, LAP_REASON reason);
 241
 242 void irlap_status_indication(struct irlap_cb *, int quality_of_link);
 243
 244 void irlap_test_request(__u8 *info, int len);
 245
 246 void irlap_discovery_request(struct irlap_cb *, discovery_t *discovery);
 247 void irlap_discovery_confirm(struct irlap_cb *, hashbin_t *discovery_log);
 248 void irlap_discovery_indication(struct irlap_cb *, discovery_t *discovery);
 249
 250 void irlap_reset_indication(struct irlap_cb *self);
 251 void irlap_reset_confirm(void);
 252
 253 void irlap_update_nr_received(struct irlap_cb *, int nr);
 254 int irlap_validate_nr_received(struct irlap_cb *, int nr);
 255 int irlap_validate_ns_received(struct irlap_cb *, int ns);
 256
 257 int  irlap_generate_rand_time_slot(int S, int s);
 258 void irlap_initiate_connection_state(struct irlap_cb *);
 259 void irlap_flush_all_queues(struct irlap_cb *);
 260 void irlap_wait_min_turn_around(struct irlap_cb *, struct qos_info *);
 261
 262 void irlap_apply_default_connection_parameters(struct irlap_cb *self);
 263 void irlap_apply_connection_parameters(struct irlap_cb *self, int now);
 264
 265 #define IRLAP_GET_HEADER_SIZE(self) (LAP_MAX_HEADER)
 266 #define IRLAP_GET_TX_QUEUE_LEN(self) skb_queue_len(&self->txq)
 267
 268 /* Return TRUE if the node is in primary mode (i.e. master)
 269  * - Jean II */
 270 static inline int irlap_is_primary(struct irlap_cb *self)
 271 {
 272         int ret;
 273         switch(self->state) {
 274         case LAP_XMIT_P:
 275         case LAP_NRM_P:
 276                 ret = 1;
 277                 break;
 278         case LAP_XMIT_S:
 279         case LAP_NRM_S:
 280                 ret = 0;
 281                 break;
 282         default:
 283                 ret = -1;
 284         }
 285         return ret;
 286 }
 287
 288 /* Clear a pending IrLAP disconnect. - Jean II */
 289 static inline void irlap_clear_disconnect(struct irlap_cb *self)
 290 {
 291         self->disconnect_pending = FALSE;
 292 }
 293
 294 /*
 295  * Function irlap_next_state (self, state)
 296  *
 297  *    Switches state and provides debug information
 298  *
 299  */
 300 static inline void irlap_next_state(struct irlap_cb *self, IRLAP_STATE state)
 301 {
 302         /*
 303         if (!self || self->magic != LAP_MAGIC)
 304                 return;
 305
 306         IRDA_DEBUG(4, "next LAP state = %s\n", irlap_state[state]);
 307         */
 308         self->state = state;
 309 }
 310
 311 #endif