1 /*********************************************************************
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>
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>
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.
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.
25 ********************************************************************/
30 #include <linux/types.h>
31 #include <linux/skbuff.h>
32 #include <linux/netdevice.h>
33 #include <linux/timer.h>
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 */
41 #define CONFIG_IRDA_DYNAMIC_WINDOW 1
43 #define LAP_RELIABLE 1
44 #define LAP_UNRELIABLE 0
46 #define LAP_ADDR_HEADER 1 /* IrLAP Address Header */
47 #define LAP_CTRL_HEADER 1 /* IrLAP Control Header */
49 /* May be different when we get VFIR */
50 #define LAP_MAX_HEADER (LAP_ADDR_HEADER + LAP_CTRL_HEADER)
52 /* Each IrDA device gets a random 32 bits IRLAP device address */
55 #define BROADCAST 0xffffffff /* Broadcast device address */
56 #define CBROADCAST 0xfe /* Connection broadcast address */
57 #define XID_FORMAT 0x01 /* Discovery XID format */
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.
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.
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.
87 #define NR_UNEXPECTED 0
91 #define NS_UNEXPECTED 0
95 * Meta information passed within the IrLAP state machine
98 __u8 caddr; /* Connection address */
99 __u8 control; /* Frame type */
105 int pf; /* Poll/final bit set */
107 __u8 nr; /* Sequence number of next frame expected */
108 __u8 ns; /* Sequence number of frame sent */
110 int S; /* Number of slots */
111 int slot; /* Random chosen slot */
112 int s; /* Current slot */
114 discovery_t *discovery; /* Discovery information */
117 /* Main structure of IrLAP */
119 irda_queue_t q; /* Must be first */
122 /* Device we are attached to */
123 struct net_device *netdev;
124 char hw_name[2*IFNAMSIZ + 1];
126 /* Connection state */
127 volatile IRLAP_STATE state; /* Current state */
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;
138 /* Media busy stuff */
139 struct timer_list media_busy_timer;
142 /* Timeouts which will be different with different turn time */
148 struct sk_buff_head txq; /* Frames to be transmitted */
149 struct sk_buff_head txq_ultra;
151 __u8 caddr; /* Connection address */
152 __u32 saddr; /* Source device address */
153 __u32 daddr; /* Destination device address */
155 int retry_count; /* Times tried to establish connection */
156 int add_wait; /* True if we are waiting for frame */
158 __u8 connect_pending;
159 __u8 disconnect_pending;
161 /* To send a faster RR if tx queue empty */
162 #ifdef CONFIG_IRDA_FAST_RR
165 #endif /* CONFIG_IRDA_FAST_RR */
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 */
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 */
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 */
186 struct sk_buff_head wx_list;
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? */
196 hashbin_t *discovery_log;
197 discovery_t *discovery_cmd;
199 __u32 speed; /* Link speed */
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 */
205 notify_t notify; /* Callbacks to IrLMP */
207 int mtt_required; /* Minumum 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 */
212 int mode; /* IrLAP mode (primary, secondary or monitor) */
216 * Function prototypes
218 int irlap_init(void);
219 void irlap_cleanup(void);
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);
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);
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);
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 */
239 void irlap_disconnect_request(struct irlap_cb *);
240 void irlap_disconnect_indication(struct irlap_cb *, LAP_REASON reason);
242 void irlap_status_indication(struct irlap_cb *, int quality_of_link);
244 void irlap_test_request(__u8 *info, int len);
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);
250 void irlap_reset_indication(struct irlap_cb *self);
251 void irlap_reset_confirm(void);
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);
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 *);
262 void irlap_apply_default_connection_parameters(struct irlap_cb *self);
263 void irlap_apply_connection_parameters(struct irlap_cb *self, int now);
265 #define IRLAP_GET_HEADER_SIZE(self) (LAP_MAX_HEADER)
266 #define IRLAP_GET_TX_QUEUE_LEN(self) skb_queue_len(&self->txq)
268 /* Return TRUE if the node is in primary mode (i.e. master)
270 static inline int irlap_is_primary(struct irlap_cb *self)
273 switch(self->state) {
288 /* Clear a pending IrLAP disconnect. - Jean II */
289 static inline void irlap_clear_disconnect(struct irlap_cb *self)
291 self->disconnect_pending = FALSE;
295 * Function irlap_next_state (self, state)
297 * Switches state and provides debug information
300 static inline void irlap_next_state(struct irlap_cb *self, IRLAP_STATE state)
303 if (!self || self->magic != LAP_MAGIC)
306 IRDA_DEBUG(4, "next LAP state = %s\n", irlap_state[state]);