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