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