1 /*********************************************************************
2  *
3  * Filename:      qos.c
4  * Version:       1.0
5  * Description:   IrLAP QoS parameter negotiation
6  * Status:        Stable
7  * Author:        Dag Brattli <dagb@cs.uit.no>
8  * Created at:    Tue Sep  9 00:00:26 1997
9  * Modified at:   Sun Jan 30 14:29:16 2000
10  * Modified by:   Dag Brattli <dagb@cs.uit.no>
11  *
12  *     Copyright (c) 1998-2000 Dag Brattli <dagb@cs.uit.no>,
13  *     All Rights Reserved.
14  *     Copyright (c) 2000-2001 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  *     This program is distributed in the hope that it will be useful,
22  *     but WITHOUT ANY WARRANTY; without even the implied warranty of
23  *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
24  *     GNU General Public License for more details.
25  *
26  *     You should have received a copy of the GNU General Public License
27  *     along with this program; if not, write to the Free Software
28  *     Foundation, Inc., 59 Temple Place, Suite 330, Boston,
29  *     MA 02111-1307 USA
30  *
31  ********************************************************************/
32 
33 #include <linux/config.h>
34 #include <asm/byteorder.h>
35 
36 #include <net/irda/irda.h>
37 #include <net/irda/parameters.h>
38 #include <net/irda/qos.h>
39 #include <net/irda/irlap.h>
40 
41 /*
42  * Maximum values of the baud rate we negociate with the other end.
43  * Most often, you don't have to change that, because Linux-IrDA will
44  * use the maximum offered by the link layer, which usually works fine.
45  * In some very rare cases, you may want to limit it to lower speeds...
46  */
47 int sysctl_max_baud_rate = 16000000;
48 /*
49  * Maximum value of the lap disconnect timer we negociate with the other end.
50  * Most often, the value below represent the best compromise, but some user
51  * may want to keep the LAP alive longuer or shorter in case of link failure.
52  * Remember that the threshold time (early warning) is fixed to 3s...
53  */
54 int sysctl_max_noreply_time = 12;
55 /*
56  * Minimum turn time to be applied before transmitting to the peer.
57  * Nonzero values (usec) are used as lower limit to the per-connection
58  * mtt value which was announced by the other end during negotiation.
59  * Might be helpful if the peer device provides too short mtt.
60  * Default is 10us which means using the unmodified value given by the
61  * peer except if it's 0 (0 is likely a bug in the other stack).
62  */
63 unsigned sysctl_min_tx_turn_time = 10;
64 /*
65  * Maximum data size to be used in transmission in payload of LAP frame.
66  * There is a bit of confusion in the IrDA spec :
67  * The LAP spec defines the payload of a LAP frame (I field) to be
68  * 2048 bytes max (IrLAP 1.1, chapt 6.6.5, p40).
69  * On the other hand, the PHY mention frames of 2048 bytes max (IrPHY
70  * 1.2, chapt 5.3.2.1, p41). But, this number includes the LAP header
71  * (2 bytes), and CRC (32 bits at 4 Mb/s). So, for the I field (LAP
72  * payload), that's only 2042 bytes. Oups !
73  * My nsc-ircc hardware has troubles receiving 2048 bytes frames at 4 Mb/s,
74  * so adjust to 2042... I don't know if this bug applies only for 2048
75  * bytes frames or all negociated frame sizes, but you can use the sysctl
76  * to play with this value anyway.
77  * Jean II */
78 unsigned sysctl_max_tx_data_size = 2042;
79 /*
80  * Maximum transmit window, i.e. number of LAP frames between turn-around.
81  * This allow to override what the peer told us. Some peers are buggy and
82  * don't always support what they tell us.
83  * Jean II */
84 unsigned sysctl_max_tx_window = 7;
85 
86 static int irlap_param_baud_rate(void *instance, irda_param_t *param, int get);
87 static int irlap_param_link_disconnect(void *instance, irda_param_t *parm,
88 				       int get);
89 static int irlap_param_max_turn_time(void *instance, irda_param_t *param,
90 				     int get);
91 static int irlap_param_data_size(void *instance, irda_param_t *param, int get);
92 static int irlap_param_window_size(void *instance, irda_param_t *param,
93 				   int get);
94 static int irlap_param_additional_bofs(void *instance, irda_param_t *parm,
95 				       int get);
96 static int irlap_param_min_turn_time(void *instance, irda_param_t *param,
97 				     int get);
98 
99 __u32 min_turn_times[]  = { 10000, 5000, 1000, 500, 100, 50, 10, 0 }; /* us */
100 static __u32 baud_rates[] = { 2400, 9600, 19200, 38400, 57600, 115200, 576000,
101 			    1152000, 4000000, 16000000 };           /* bps */
102 __u32 data_sizes[]      = { 64, 128, 256, 512, 1024, 2048 };        /* bytes */
103 __u32 add_bofs[]        = { 48, 24, 12, 5, 3, 2, 1, 0 };            /* bytes */
104 __u32 max_turn_times[]  = { 500, 250, 100, 50 };                    /* ms */
105 __u32 link_disc_times[] = { 3, 8, 12, 16, 20, 25, 30, 40 };         /* secs */
106 
107 __u32 max_line_capacities[10][4] = {
108        /* 500 ms     250 ms  100 ms  50 ms (max turn time) */
109 	{    100,      0,      0,     0 }, /*     2400 bps */
110 	{    400,      0,      0,     0 }, /*     9600 bps */
111 	{    800,      0,      0,     0 }, /*    19200 bps */
112 	{   1600,      0,      0,     0 }, /*    38400 bps */
113 	{   2360,      0,      0,     0 }, /*    57600 bps */
114 	{   4800,   2400,    960,   480 }, /*   115200 bps */
115 	{  28800,  11520,   5760,  2880 }, /*   576000 bps */
116 	{  57600,  28800,  11520,  5760 }, /*  1152000 bps */
117 	{ 200000, 100000,  40000, 20000 }, /*  4000000 bps */
118 	{ 800000, 400000, 160000, 80000 }, /* 16000000 bps */
119 };
120 
121 static pi_minor_info_t pi_minor_call_table_type_0[] = {
122 	{ NULL, 0 },
123 /* 01 */{ irlap_param_baud_rate,       PV_INTEGER | PV_LITTLE_ENDIAN },
124 	{ NULL, 0 },
125 	{ NULL, 0 },
126 	{ NULL, 0 },
127 	{ NULL, 0 },
128 	{ NULL, 0 },
129 	{ NULL, 0 },
130 /* 08 */{ irlap_param_link_disconnect, PV_INT_8_BITS }
131 };
132 
133 static pi_minor_info_t pi_minor_call_table_type_1[] = {
134 	{ NULL, 0 },
135 	{ NULL, 0 },
136 /* 82 */{ irlap_param_max_turn_time,   PV_INT_8_BITS },
137 /* 83 */{ irlap_param_data_size,       PV_INT_8_BITS },
138 /* 84 */{ irlap_param_window_size,     PV_INT_8_BITS },
139 /* 85 */{ irlap_param_additional_bofs, PV_INT_8_BITS },
140 /* 86 */{ irlap_param_min_turn_time,   PV_INT_8_BITS },
141 };
142 
143 static pi_major_info_t pi_major_call_table[] = {
144 	{ pi_minor_call_table_type_0, 9 },
145 	{ pi_minor_call_table_type_1, 7 },
146 };
147 
148 static pi_param_info_t irlap_param_info = { pi_major_call_table, 2, 0x7f, 7 };
149 
150 /* ---------------------- LOCAL SUBROUTINES ---------------------- */
151 /* Note : we start with a bunch of local subroutines.
152  * As the compiler is "one pass", this is the only way to get them to
153  * inline properly...
154  * Jean II
155  */
156 /*
157  * Function value_index (value, array, size)
158  *
159  *    Returns the index to the value in the specified array
160  */
value_index(__u32 value,__u32 * array,int size)161 static inline int value_index(__u32 value, __u32 *array, int size)
162 {
163 	int i;
164 
165 	for (i=0; i < size; i++)
166 		if (array[i] == value)
167 			break;
168 	return i;
169 }
170 
171 /*
172  * Function index_value (index, array)
173  *
174  *    Returns value to index in array, easy!
175  *
176  */
index_value(int index,__u32 * array)177 static inline __u32 index_value(int index, __u32 *array)
178 {
179 	return array[index];
180 }
181 
182 /*
183  * Function msb_index (word)
184  *
185  *    Returns index to most significant bit (MSB) in word
186  *
187  */
msb_index(__u16 word)188 int msb_index (__u16 word)
189 {
190 	__u16 msb = 0x8000;
191 	int index = 15;   /* Current MSB */
192 
193 	/* Check for buggy peers.
194 	 * Note : there is a small probability that it could be us, but I
195 	 * would expect driver authors to catch that pretty early and be
196 	 * able to check precisely what's going on. If a end user sees this,
197 	 * it's very likely the peer. - Jean II */
198 	if (word == 0) {
199 		WARNING("%s(), Detected buggy peer, adjust null PV to 0x1!\n",
200 			 __FUNCTION__);
201 		/* The only safe choice (we don't know the array size) */
202 		word = 0x1;
203 	}
204 
205 	while (msb) {
206 		if (word & msb)
207 			break;   /* Found it! */
208 		msb >>=1;
209 		index--;
210 	}
211 	return index;
212 }
213 
byte_value(__u8 byte,__u32 * array)214 static inline __u32 byte_value(__u8 byte, __u32 *array)
215 {
216 	int index;
217 
218 	ASSERT(array != NULL, return -1;);
219 
220 	index = msb_index(byte);
221 
222 	return index_value(index, array);
223 }
224 
225 /*
226  * Function value_lower_bits (value, array)
227  *
228  *    Returns a bit field marking all possibility lower than value.
229  */
value_lower_bits(__u32 value,__u32 * array,int size,__u16 * field)230 static inline int value_lower_bits(__u32 value, __u32 *array, int size, __u16 *field)
231 {
232 	int	i;
233 	__u16	mask = 0x1;
234 	__u16	result = 0x0;
235 
236 	for (i=0; i < size; i++) {
237 		/* Add the current value to the bit field, shift mask */
238 		result |= mask;
239 		mask <<= 1;
240 		/* Finished ? */
241 		if (array[i] >= value)
242 			break;
243 	}
244 	/* Send back a valid index */
245 	if(i >= size)
246 	  i = size - 1;	/* Last item */
247 	*field = result;
248 	return i;
249 }
250 
251 /*
252  * Function value_highest_bit (value, array)
253  *
254  *    Returns a bit field marking the highest possibility lower than value.
255  */
value_highest_bit(__u32 value,__u32 * array,int size,__u16 * field)256 static inline int value_highest_bit(__u32 value, __u32 *array, int size, __u16 *field)
257 {
258 	int	i;
259 	__u16	mask = 0x1;
260 	__u16	result = 0x0;
261 
262 	for (i=0; i < size; i++) {
263 		/* Finished ? */
264 		if (array[i] <= value)
265 			break;
266 		/* Shift mask */
267 		mask <<= 1;
268 	}
269 	/* Set the current value to the bit field */
270 	result |= mask;
271 	/* Send back a valid index */
272 	if(i >= size)
273 	  i = size - 1;	/* Last item */
274 	*field = result;
275 	return i;
276 }
277 
278 /* -------------------------- MAIN CALLS -------------------------- */
279 
280 /*
281  * Function irda_qos_compute_intersection (qos, new)
282  *
283  *    Compute the intersection of the old QoS capabilites with new ones
284  *
285  */
irda_qos_compute_intersection(struct qos_info * qos,struct qos_info * new)286 void irda_qos_compute_intersection(struct qos_info *qos, struct qos_info *new)
287 {
288 	ASSERT(qos != NULL, return;);
289 	ASSERT(new != NULL, return;);
290 
291 	/* Apply */
292 	qos->baud_rate.bits       &= new->baud_rate.bits;
293 	qos->window_size.bits     &= new->window_size.bits;
294 	qos->min_turn_time.bits   &= new->min_turn_time.bits;
295 	qos->max_turn_time.bits   &= new->max_turn_time.bits;
296 	qos->data_size.bits       &= new->data_size.bits;
297 	qos->link_disc_time.bits  &= new->link_disc_time.bits;
298 	qos->additional_bofs.bits &= new->additional_bofs.bits;
299 
300 	irda_qos_bits_to_value(qos);
301 }
302 
303 /*
304  * Function irda_init_max_qos_capabilies (qos)
305  *
306  *    The purpose of this function is for layers and drivers to be able to
307  *    set the maximum QoS possible and then "and in" their own limitations
308  *
309  */
irda_init_max_qos_capabilies(struct qos_info * qos)310 void irda_init_max_qos_capabilies(struct qos_info *qos)
311 {
312 	int i;
313 	/*
314 	 *  These are the maximum supported values as specified on pages
315 	 *  39-43 in IrLAP
316 	 */
317 
318 	/* Use sysctl to set some configurable values... */
319 	/* Set configured max speed */
320 	i = value_lower_bits(sysctl_max_baud_rate, baud_rates, 10,
321 			     &qos->baud_rate.bits);
322 	sysctl_max_baud_rate = index_value(i, baud_rates);
323 
324 	/* Set configured max disc time */
325 	i = value_lower_bits(sysctl_max_noreply_time, link_disc_times, 8,
326 			     &qos->link_disc_time.bits);
327 	sysctl_max_noreply_time = index_value(i, link_disc_times);
328 
329 	/* LSB is first byte, MSB is second byte */
330 	qos->baud_rate.bits    &= 0x03ff;
331 
332 	qos->window_size.bits     = 0x7f;
333 	qos->min_turn_time.bits   = 0xff;
334 	qos->max_turn_time.bits   = 0x0f;
335 	qos->data_size.bits       = 0x3f;
336 	qos->link_disc_time.bits &= 0xff;
337 	qos->additional_bofs.bits = 0xff;
338 }
339 
340 /*
341  * Function irlap_adjust_qos_settings (qos)
342  *
343  *     Adjust QoS settings in case some values are not possible to use because
344  *     of other settings
345  */
irlap_adjust_qos_settings(struct qos_info * qos)346 void irlap_adjust_qos_settings(struct qos_info *qos)
347 {
348 	__u32 line_capacity;
349 	int index;
350 
351 	IRDA_DEBUG(2, "%s()\n", __FUNCTION__);
352 
353 	/*
354 	 * Make sure the mintt is sensible.
355 	 * Main culprit : Ericsson T39. - Jean II
356 	 */
357 	if (sysctl_min_tx_turn_time > qos->min_turn_time.value) {
358 		int i;
359 
360 		WARNING("%s(), Detected buggy peer, adjust mtt to %dus!\n",
361 			 __FUNCTION__, sysctl_min_tx_turn_time);
362 
363 		/* We don't really need bits, but easier this way */
364 		i = value_highest_bit(sysctl_min_tx_turn_time, min_turn_times,
365 				      8, &qos->min_turn_time.bits);
366 		sysctl_min_tx_turn_time = index_value(i, min_turn_times);
367 		qos->min_turn_time.value = sysctl_min_tx_turn_time;
368 	}
369 
370 	/*
371 	 * Not allowed to use a max turn time less than 500 ms if the baudrate
372 	 * is less than 115200
373 	 */
374 	if ((qos->baud_rate.value < 115200) &&
375 	    (qos->max_turn_time.value < 500))
376 	{
377 		IRDA_DEBUG(0, "%s(), adjusting max turn time from %d to 500 ms\n", __FUNCTION__,
378 			   qos->max_turn_time.value);
379 		qos->max_turn_time.value = 500;
380 	}
381 
382 	/*
383 	 * The data size must be adjusted according to the baud rate and max
384 	 * turn time
385 	 */
386 	index = value_index(qos->data_size.value, data_sizes, 6);
387 	line_capacity = irlap_max_line_capacity(qos->baud_rate.value,
388 						qos->max_turn_time.value);
389 
390 #ifdef CONFIG_IRDA_DYNAMIC_WINDOW
391 	while ((qos->data_size.value > line_capacity) && (index > 0)) {
392 		qos->data_size.value = data_sizes[index--];
393 		IRDA_DEBUG(2, "%s(), reducing data size to %d\n", __FUNCTION__,
394 			   qos->data_size.value);
395 	}
396 #else /* Use method described in section 6.6.11 of IrLAP */
397 	while (irlap_requested_line_capacity(qos) > line_capacity) {
398 		ASSERT(index != 0, return;);
399 
400 		/* Must be able to send at least one frame */
401 		if (qos->window_size.value > 1) {
402 			qos->window_size.value--;
403 			IRDA_DEBUG(2, "%s(), reducing window size to %d\n", __FUNCTION__,
404 				   qos->window_size.value);
405 		} else if (index > 1) {
406 			qos->data_size.value = data_sizes[index--];
407 			IRDA_DEBUG(2, "%s(), reducing data size to %d\n", __FUNCTION__,
408 				   qos->data_size.value);
409 		} else {
410 			WARNING("%s(), nothing more we can do!\n", __FUNCTION__);
411 		}
412 	}
413 #endif /* CONFIG_IRDA_DYNAMIC_WINDOW */
414 	/*
415 	 * Fix tx data size according to user limits - Jean II
416 	 */
417 	if (qos->data_size.value > sysctl_max_tx_data_size)
418 		/* Allow non discrete adjustement to avoid loosing capacity */
419 		qos->data_size.value = sysctl_max_tx_data_size;
420 	/*
421 	 * Override Tx window if user request it. - Jean II
422 	 */
423 	if (qos->window_size.value > sysctl_max_tx_window)
424 		qos->window_size.value = sysctl_max_tx_window;
425 }
426 
427 /*
428  * Function irlap_negotiate (qos_device, qos_session, skb)
429  *
430  *    Negotiate QoS values, not really that much negotiation :-)
431  *    We just set the QoS capabilities for the peer station
432  *
433  */
irlap_qos_negotiate(struct irlap_cb * self,struct sk_buff * skb)434 int irlap_qos_negotiate(struct irlap_cb *self, struct sk_buff *skb)
435 {
436 	int ret;
437 
438 	ret = irda_param_extract_all(self, skb->data, skb->len,
439 				     &irlap_param_info);
440 
441 	/* Convert the negotiated bits to values */
442 	irda_qos_bits_to_value(&self->qos_tx);
443 	irda_qos_bits_to_value(&self->qos_rx);
444 
445 	irlap_adjust_qos_settings(&self->qos_tx);
446 
447 	IRDA_DEBUG(2, "Setting BAUD_RATE to %d bps.\n",
448 		   self->qos_tx.baud_rate.value);
449 	IRDA_DEBUG(2, "Setting DATA_SIZE to %d bytes\n",
450 		   self->qos_tx.data_size.value);
451 	IRDA_DEBUG(2, "Setting WINDOW_SIZE to %d\n",
452 		   self->qos_tx.window_size.value);
453 	IRDA_DEBUG(2, "Setting XBOFS to %d\n",
454 		   self->qos_tx.additional_bofs.value);
455 	IRDA_DEBUG(2, "Setting MAX_TURN_TIME to %d ms.\n",
456 		   self->qos_tx.max_turn_time.value);
457 	IRDA_DEBUG(2, "Setting MIN_TURN_TIME to %d usecs.\n",
458 		   self->qos_tx.min_turn_time.value);
459 	IRDA_DEBUG(2, "Setting LINK_DISC to %d secs.\n",
460 		   self->qos_tx.link_disc_time.value);
461 	return ret;
462 }
463 
464 /*
465  * Function irlap_insert_negotiation_params (qos, fp)
466  *
467  *    Insert QoS negotiaion pararameters into frame
468  *
469  */
irlap_insert_qos_negotiation_params(struct irlap_cb * self,struct sk_buff * skb)470 int irlap_insert_qos_negotiation_params(struct irlap_cb *self,
471 					struct sk_buff *skb)
472 {
473 	int ret;
474 
475 	/* Insert data rate */
476 	ret = irda_param_insert(self, PI_BAUD_RATE, skb->tail,
477 				skb_tailroom(skb), &irlap_param_info);
478 	if (ret < 0)
479 		return ret;
480 	skb_put(skb, ret);
481 
482 	/* Insert max turnaround time */
483 	ret = irda_param_insert(self, PI_MAX_TURN_TIME, skb->tail,
484 				skb_tailroom(skb), &irlap_param_info);
485 	if (ret < 0)
486 		return ret;
487 	skb_put(skb, ret);
488 
489 	/* Insert data size */
490 	ret = irda_param_insert(self, PI_DATA_SIZE, skb->tail,
491 				skb_tailroom(skb), &irlap_param_info);
492 	if (ret < 0)
493 		return ret;
494 	skb_put(skb, ret);
495 
496 	/* Insert window size */
497 	ret = irda_param_insert(self, PI_WINDOW_SIZE, skb->tail,
498 				skb_tailroom(skb), &irlap_param_info);
499 	if (ret < 0)
500 		return ret;
501 	skb_put(skb, ret);
502 
503 	/* Insert additional BOFs */
504 	ret = irda_param_insert(self, PI_ADD_BOFS, skb->tail,
505 				skb_tailroom(skb), &irlap_param_info);
506 	if (ret < 0)
507 		return ret;
508 	skb_put(skb, ret);
509 
510 	/* Insert minimum turnaround time */
511 	ret = irda_param_insert(self, PI_MIN_TURN_TIME, skb->tail,
512 				skb_tailroom(skb), &irlap_param_info);
513 	if (ret < 0)
514 		return ret;
515 	skb_put(skb, ret);
516 
517 	/* Insert link disconnect/threshold time */
518 	ret = irda_param_insert(self, PI_LINK_DISC, skb->tail,
519 				skb_tailroom(skb), &irlap_param_info);
520 	if (ret < 0)
521 		return ret;
522 	skb_put(skb, ret);
523 
524 	return 0;
525 }
526 
527 /*
528  * Function irlap_param_baud_rate (instance, param, get)
529  *
530  *    Negotiate data-rate
531  *
532  */
irlap_param_baud_rate(void * instance,irda_param_t * param,int get)533 static int irlap_param_baud_rate(void *instance, irda_param_t *param, int get)
534 {
535 	__u16 final;
536 
537 	struct irlap_cb *self = (struct irlap_cb *) instance;
538 
539 	ASSERT(self != NULL, return -1;);
540 	ASSERT(self->magic == LAP_MAGIC, return -1;);
541 
542 	if (get) {
543 		param->pv.i = self->qos_rx.baud_rate.bits;
544 		IRDA_DEBUG(2, "%s(), baud rate = 0x%02x\n", __FUNCTION__,
545 			   param->pv.i);
546 	} else {
547 		/*
548 		 *  Stations must agree on baud rate, so calculate
549 		 *  intersection
550 		 */
551 		IRDA_DEBUG(2, "Requested BAUD_RATE: 0x%04x\n", (__u16) param->pv.i);
552 		final = (__u16) param->pv.i & self->qos_rx.baud_rate.bits;
553 
554 		IRDA_DEBUG(2, "Final BAUD_RATE: 0x%04x\n", final);
555 		self->qos_tx.baud_rate.bits = final;
556 		self->qos_rx.baud_rate.bits = final;
557 	}
558 
559 	return 0;
560 }
561 
562 /*
563  * Function irlap_param_link_disconnect (instance, param, get)
564  *
565  *    Negotiate link disconnect/threshold time.
566  *
567  */
irlap_param_link_disconnect(void * instance,irda_param_t * param,int get)568 static int irlap_param_link_disconnect(void *instance, irda_param_t *param,
569 				       int get)
570 {
571 	__u16 final;
572 
573 	struct irlap_cb *self = (struct irlap_cb *) instance;
574 
575 	ASSERT(self != NULL, return -1;);
576 	ASSERT(self->magic == LAP_MAGIC, return -1;);
577 
578 	if (get)
579 		param->pv.i = self->qos_rx.link_disc_time.bits;
580 	else {
581 		/*
582 		 *  Stations must agree on link disconnect/threshold
583 		 *  time.
584 		 */
585 		IRDA_DEBUG(2, "LINK_DISC: %02x\n", (__u8) param->pv.i);
586 		final = (__u8) param->pv.i & self->qos_rx.link_disc_time.bits;
587 
588 		IRDA_DEBUG(2, "Final LINK_DISC: %02x\n", final);
589 		self->qos_tx.link_disc_time.bits = final;
590 		self->qos_rx.link_disc_time.bits = final;
591 	}
592 	return 0;
593 }
594 
595 /*
596  * Function irlap_param_max_turn_time (instance, param, get)
597  *
598  *    Negotiate the maximum turnaround time. This is a type 1 parameter and
599  *    will be negotiated independently for each station
600  *
601  */
irlap_param_max_turn_time(void * instance,irda_param_t * param,int get)602 static int irlap_param_max_turn_time(void *instance, irda_param_t *param,
603 				     int get)
604 {
605 	struct irlap_cb *self = (struct irlap_cb *) instance;
606 
607 	ASSERT(self != NULL, return -1;);
608 	ASSERT(self->magic == LAP_MAGIC, return -1;);
609 
610 	if (get)
611 		param->pv.i = self->qos_rx.max_turn_time.bits;
612 	else
613 		self->qos_tx.max_turn_time.bits = (__u8) param->pv.i;
614 
615 	return 0;
616 }
617 
618 /*
619  * Function irlap_param_data_size (instance, param, get)
620  *
621  *    Negotiate the data size. This is a type 1 parameter and
622  *    will be negotiated independently for each station
623  *
624  */
irlap_param_data_size(void * instance,irda_param_t * param,int get)625 static int irlap_param_data_size(void *instance, irda_param_t *param, int get)
626 {
627 	struct irlap_cb *self = (struct irlap_cb *) instance;
628 
629 	ASSERT(self != NULL, return -1;);
630 	ASSERT(self->magic == LAP_MAGIC, return -1;);
631 
632 	if (get)
633 		param->pv.i = self->qos_rx.data_size.bits;
634 	else
635 		self->qos_tx.data_size.bits = (__u8) param->pv.i;
636 
637 	return 0;
638 }
639 
640 /*
641  * Function irlap_param_window_size (instance, param, get)
642  *
643  *    Negotiate the window size. This is a type 1 parameter and
644  *    will be negotiated independently for each station
645  *
646  */
irlap_param_window_size(void * instance,irda_param_t * param,int get)647 static int irlap_param_window_size(void *instance, irda_param_t *param,
648 				   int get)
649 {
650 	struct irlap_cb *self = (struct irlap_cb *) instance;
651 
652 	ASSERT(self != NULL, return -1;);
653 	ASSERT(self->magic == LAP_MAGIC, return -1;);
654 
655 	if (get)
656 		param->pv.i = self->qos_rx.window_size.bits;
657 	else
658 		self->qos_tx.window_size.bits = (__u8) param->pv.i;
659 
660 	return 0;
661 }
662 
663 /*
664  * Function irlap_param_additional_bofs (instance, param, get)
665  *
666  *    Negotiate additional BOF characters. This is a type 1 parameter and
667  *    will be negotiated independently for each station.
668  */
irlap_param_additional_bofs(void * instance,irda_param_t * param,int get)669 static int irlap_param_additional_bofs(void *instance, irda_param_t *param, int get)
670 {
671 	struct irlap_cb *self = (struct irlap_cb *) instance;
672 
673 	ASSERT(self != NULL, return -1;);
674 	ASSERT(self->magic == LAP_MAGIC, return -1;);
675 
676 	if (get)
677 		param->pv.i = self->qos_rx.additional_bofs.bits;
678 	else
679 		self->qos_tx.additional_bofs.bits = (__u8) param->pv.i;
680 
681 	return 0;
682 }
683 
684 /*
685  * Function irlap_param_min_turn_time (instance, param, get)
686  *
687  *    Negotiate the minimum turn around time. This is a type 1 parameter and
688  *    will be negotiated independently for each station
689  */
irlap_param_min_turn_time(void * instance,irda_param_t * param,int get)690 static int irlap_param_min_turn_time(void *instance, irda_param_t *param,
691 				     int get)
692 {
693 	struct irlap_cb *self = (struct irlap_cb *) instance;
694 
695 	ASSERT(self != NULL, return -1;);
696 	ASSERT(self->magic == LAP_MAGIC, return -1;);
697 
698 	if (get)
699 		param->pv.i = self->qos_rx.min_turn_time.bits;
700 	else
701 		self->qos_tx.min_turn_time.bits = (__u8) param->pv.i;
702 
703 	return 0;
704 }
705 
706 /*
707  * Function irlap_max_line_capacity (speed, max_turn_time, min_turn_time)
708  *
709  *    Calculate the maximum line capacity
710  *
711  */
irlap_max_line_capacity(__u32 speed,__u32 max_turn_time)712 __u32 irlap_max_line_capacity(__u32 speed, __u32 max_turn_time)
713 {
714 	__u32 line_capacity;
715 	int i,j;
716 
717 	IRDA_DEBUG(2, "%s(), speed=%d, max_turn_time=%d\n", __FUNCTION__,
718 		   speed, max_turn_time);
719 
720 	i = value_index(speed, baud_rates, 10);
721 	j = value_index(max_turn_time, max_turn_times, 4);
722 
723 	ASSERT(((i >=0) && (i <=10)), return 0;);
724 	ASSERT(((j >=0) && (j <=4)), return 0;);
725 
726 	line_capacity = max_line_capacities[i][j];
727 
728 	IRDA_DEBUG(2, "%s(), line capacity=%d bytes\n", __FUNCTION__,
729 		   line_capacity);
730 
731 	return line_capacity;
732 }
733 
irlap_requested_line_capacity(struct qos_info * qos)734 __u32 irlap_requested_line_capacity(struct qos_info *qos)
735 {	__u32 line_capacity;
736 
737 	line_capacity = qos->window_size.value *
738 		(qos->data_size.value + 6 + qos->additional_bofs.value) +
739 		irlap_min_turn_time_in_bytes(qos->baud_rate.value,
740 					     qos->min_turn_time.value);
741 
742 	IRDA_DEBUG(2, "%s(), requested line capacity=%d\n", __FUNCTION__,
743 		   line_capacity);
744 
745 	return line_capacity;
746 }
747 
irda_qos_bits_to_value(struct qos_info * qos)748 void irda_qos_bits_to_value(struct qos_info *qos)
749 {
750 	int index;
751 
752 	ASSERT(qos != NULL, return;);
753 
754 	index = msb_index(qos->baud_rate.bits);
755 	qos->baud_rate.value = baud_rates[index];
756 
757 	index = msb_index(qos->data_size.bits);
758 	qos->data_size.value = data_sizes[index];
759 
760 	index = msb_index(qos->window_size.bits);
761 	qos->window_size.value = index+1;
762 
763 	index = msb_index(qos->min_turn_time.bits);
764 	qos->min_turn_time.value = min_turn_times[index];
765 
766 	index = msb_index(qos->max_turn_time.bits);
767 	qos->max_turn_time.value = max_turn_times[index];
768 
769 	index = msb_index(qos->link_disc_time.bits);
770 	qos->link_disc_time.value = link_disc_times[index];
771 
772 	index = msb_index(qos->additional_bofs.bits);
773 	qos->additional_bofs.value = add_bofs[index];
774 }
775