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/export.h>
34 
35 #include <asm/byteorder.h>
36 
37 #include <net/irda/irda.h>
38 #include <net/irda/parameters.h>
39 #include <net/irda/qos.h>
40 #include <net/irda/irlap.h>
41 #include <net/irda/irlap_frame.h>
42 
43 /*
44  * Maximum values of the baud rate we negotiate with the other end.
45  * Most often, you don't have to change that, because Linux-IrDA will
46  * use the maximum offered by the link layer, which usually works fine.
47  * In some very rare cases, you may want to limit it to lower speeds...
48  */
49 int sysctl_max_baud_rate = 16000000;
50 /*
51  * Maximum value of the lap disconnect timer we negotiate with the other end.
52  * Most often, the value below represent the best compromise, but some user
53  * may want to keep the LAP alive longer or shorter in case of link failure.
54  * Remember that the threshold time (early warning) is fixed to 3s...
55  */
56 int sysctl_max_noreply_time = 12;
57 /*
58  * Minimum turn time to be applied before transmitting to the peer.
59  * Nonzero values (usec) are used as lower limit to the per-connection
60  * mtt value which was announced by the other end during negotiation.
61  * Might be helpful if the peer device provides too short mtt.
62  * Default is 10us which means using the unmodified value given by the
63  * peer except if it's 0 (0 is likely a bug in the other stack).
64  */
65 unsigned int sysctl_min_tx_turn_time = 10;
66 /*
67  * Maximum data size to be used in transmission in payload of LAP frame.
68  * There is a bit of confusion in the IrDA spec :
69  * The LAP spec defines the payload of a LAP frame (I field) to be
70  * 2048 bytes max (IrLAP 1.1, chapt 6.6.5, p40).
71  * On the other hand, the PHY mention frames of 2048 bytes max (IrPHY
72  * 1.2, chapt 5.3.2.1, p41). But, this number includes the LAP header
73  * (2 bytes), and CRC (32 bits at 4 Mb/s). So, for the I field (LAP
74  * payload), that's only 2042 bytes. Oups !
75  * My nsc-ircc hardware has troubles receiving 2048 bytes frames at 4 Mb/s,
76  * so adjust to 2042... I don't know if this bug applies only for 2048
77  * bytes frames or all negotiated frame sizes, but you can use the sysctl
78  * to play with this value anyway.
79  * Jean II */
80 unsigned int sysctl_max_tx_data_size = 2042;
81 /*
82  * Maximum transmit window, i.e. number of LAP frames between turn-around.
83  * This allow to override what the peer told us. Some peers are buggy and
84  * don't always support what they tell us.
85  * Jean II */
86 unsigned int sysctl_max_tx_window = 7;
87 
88 static int irlap_param_baud_rate(void *instance, irda_param_t *param, int get);
89 static int irlap_param_link_disconnect(void *instance, irda_param_t *parm,
90 				       int get);
91 static int irlap_param_max_turn_time(void *instance, irda_param_t *param,
92 				     int get);
93 static int irlap_param_data_size(void *instance, irda_param_t *param, int get);
94 static int irlap_param_window_size(void *instance, irda_param_t *param,
95 				   int get);
96 static int irlap_param_additional_bofs(void *instance, irda_param_t *parm,
97 				       int get);
98 static int irlap_param_min_turn_time(void *instance, irda_param_t *param,
99 				     int get);
100 
101 #ifndef CONFIG_IRDA_DYNAMIC_WINDOW
102 static __u32 irlap_requested_line_capacity(struct qos_info *qos);
103 #endif
104 
105 static __u32 min_turn_times[]  = { 10000, 5000, 1000, 500, 100, 50, 10, 0 }; /* us */
106 static __u32 baud_rates[]      = { 2400, 9600, 19200, 38400, 57600, 115200, 576000,
107 				   1152000, 4000000, 16000000 };           /* bps */
108 static __u32 data_sizes[]      = { 64, 128, 256, 512, 1024, 2048 };        /* bytes */
109 static __u32 add_bofs[]        = { 48, 24, 12, 5, 3, 2, 1, 0 };            /* bytes */
110 static __u32 max_turn_times[]  = { 500, 250, 100, 50 };                    /* ms */
111 static __u32 link_disc_times[] = { 3, 8, 12, 16, 20, 25, 30, 40 };         /* secs */
112 
113 static __u32 max_line_capacities[10][4] = {
114        /* 500 ms     250 ms  100 ms  50 ms (max turn time) */
115 	{    100,      0,      0,     0 }, /*     2400 bps */
116 	{    400,      0,      0,     0 }, /*     9600 bps */
117 	{    800,      0,      0,     0 }, /*    19200 bps */
118 	{   1600,      0,      0,     0 }, /*    38400 bps */
119 	{   2360,      0,      0,     0 }, /*    57600 bps */
120 	{   4800,   2400,    960,   480 }, /*   115200 bps */
121 	{  28800,  11520,   5760,  2880 }, /*   576000 bps */
122 	{  57600,  28800,  11520,  5760 }, /*  1152000 bps */
123 	{ 200000, 100000,  40000, 20000 }, /*  4000000 bps */
124 	{ 800000, 400000, 160000, 80000 }, /* 16000000 bps */
125 };
126 
127 static pi_minor_info_t pi_minor_call_table_type_0[] = {
128 	{ NULL, 0 },
129 /* 01 */{ irlap_param_baud_rate,       PV_INTEGER | PV_LITTLE_ENDIAN },
130 	{ NULL, 0 },
131 	{ NULL, 0 },
132 	{ NULL, 0 },
133 	{ NULL, 0 },
134 	{ NULL, 0 },
135 	{ NULL, 0 },
136 /* 08 */{ irlap_param_link_disconnect, PV_INT_8_BITS }
137 };
138 
139 static pi_minor_info_t pi_minor_call_table_type_1[] = {
140 	{ NULL, 0 },
141 	{ NULL, 0 },
142 /* 82 */{ irlap_param_max_turn_time,   PV_INT_8_BITS },
143 /* 83 */{ irlap_param_data_size,       PV_INT_8_BITS },
144 /* 84 */{ irlap_param_window_size,     PV_INT_8_BITS },
145 /* 85 */{ irlap_param_additional_bofs, PV_INT_8_BITS },
146 /* 86 */{ irlap_param_min_turn_time,   PV_INT_8_BITS },
147 };
148 
149 static pi_major_info_t pi_major_call_table[] = {
150 	{ pi_minor_call_table_type_0, 9 },
151 	{ pi_minor_call_table_type_1, 7 },
152 };
153 
154 static pi_param_info_t irlap_param_info = { pi_major_call_table, 2, 0x7f, 7 };
155 
156 /* ---------------------- LOCAL SUBROUTINES ---------------------- */
157 /* Note : we start with a bunch of local subroutines.
158  * As the compiler is "one pass", this is the only way to get them to
159  * inline properly...
160  * Jean II
161  */
162 /*
163  * Function value_index (value, array, size)
164  *
165  *    Returns the index to the value in the specified array
166  */
value_index(__u32 value,__u32 * array,int size)167 static inline int value_index(__u32 value, __u32 *array, int size)
168 {
169 	int i;
170 
171 	for (i=0; i < size; i++)
172 		if (array[i] == value)
173 			break;
174 	return i;
175 }
176 
177 /*
178  * Function index_value (index, array)
179  *
180  *    Returns value to index in array, easy!
181  *
182  */
index_value(int index,__u32 * array)183 static inline __u32 index_value(int index, __u32 *array)
184 {
185 	return array[index];
186 }
187 
188 /*
189  * Function msb_index (word)
190  *
191  *    Returns index to most significant bit (MSB) in word
192  *
193  */
msb_index(__u16 word)194 static int msb_index (__u16 word)
195 {
196 	__u16 msb = 0x8000;
197 	int index = 15;   /* Current MSB */
198 
199 	/* Check for buggy peers.
200 	 * Note : there is a small probability that it could be us, but I
201 	 * would expect driver authors to catch that pretty early and be
202 	 * able to check precisely what's going on. If a end user sees this,
203 	 * it's very likely the peer. - Jean II */
204 	if (word == 0) {
205 		IRDA_WARNING("%s(), Detected buggy peer, adjust null PV to 0x1!\n",
206 			 __func__);
207 		/* The only safe choice (we don't know the array size) */
208 		word = 0x1;
209 	}
210 
211 	while (msb) {
212 		if (word & msb)
213 			break;   /* Found it! */
214 		msb >>=1;
215 		index--;
216 	}
217 	return index;
218 }
219 
220 /*
221  * Function value_lower_bits (value, array)
222  *
223  *    Returns a bit field marking all possibility lower than value.
224  */
value_lower_bits(__u32 value,__u32 * array,int size,__u16 * field)225 static inline int value_lower_bits(__u32 value, __u32 *array, int size, __u16 *field)
226 {
227 	int	i;
228 	__u16	mask = 0x1;
229 	__u16	result = 0x0;
230 
231 	for (i=0; i < size; i++) {
232 		/* Add the current value to the bit field, shift mask */
233 		result |= mask;
234 		mask <<= 1;
235 		/* Finished ? */
236 		if (array[i] >= value)
237 			break;
238 	}
239 	/* Send back a valid index */
240 	if(i >= size)
241 	  i = size - 1;	/* Last item */
242 	*field = result;
243 	return i;
244 }
245 
246 /*
247  * Function value_highest_bit (value, array)
248  *
249  *    Returns a bit field marking the highest possibility lower than value.
250  */
value_highest_bit(__u32 value,__u32 * array,int size,__u16 * field)251 static inline int value_highest_bit(__u32 value, __u32 *array, int size, __u16 *field)
252 {
253 	int	i;
254 	__u16	mask = 0x1;
255 	__u16	result = 0x0;
256 
257 	for (i=0; i < size; i++) {
258 		/* Finished ? */
259 		if (array[i] <= value)
260 			break;
261 		/* Shift mask */
262 		mask <<= 1;
263 	}
264 	/* Set the current value to the bit field */
265 	result |= mask;
266 	/* Send back a valid index */
267 	if(i >= size)
268 	  i = size - 1;	/* Last item */
269 	*field = result;
270 	return i;
271 }
272 
273 /* -------------------------- MAIN CALLS -------------------------- */
274 
275 /*
276  * Function irda_qos_compute_intersection (qos, new)
277  *
278  *    Compute the intersection of the old QoS capabilities with new ones
279  *
280  */
irda_qos_compute_intersection(struct qos_info * qos,struct qos_info * new)281 void irda_qos_compute_intersection(struct qos_info *qos, struct qos_info *new)
282 {
283 	IRDA_ASSERT(qos != NULL, return;);
284 	IRDA_ASSERT(new != NULL, return;);
285 
286 	/* Apply */
287 	qos->baud_rate.bits       &= new->baud_rate.bits;
288 	qos->window_size.bits     &= new->window_size.bits;
289 	qos->min_turn_time.bits   &= new->min_turn_time.bits;
290 	qos->max_turn_time.bits   &= new->max_turn_time.bits;
291 	qos->data_size.bits       &= new->data_size.bits;
292 	qos->link_disc_time.bits  &= new->link_disc_time.bits;
293 	qos->additional_bofs.bits &= new->additional_bofs.bits;
294 
295 	irda_qos_bits_to_value(qos);
296 }
297 
298 /*
299  * Function irda_init_max_qos_capabilies (qos)
300  *
301  *    The purpose of this function is for layers and drivers to be able to
302  *    set the maximum QoS possible and then "and in" their own limitations
303  *
304  */
irda_init_max_qos_capabilies(struct qos_info * qos)305 void irda_init_max_qos_capabilies(struct qos_info *qos)
306 {
307 	int i;
308 	/*
309 	 *  These are the maximum supported values as specified on pages
310 	 *  39-43 in IrLAP
311 	 */
312 
313 	/* Use sysctl to set some configurable values... */
314 	/* Set configured max speed */
315 	i = value_lower_bits(sysctl_max_baud_rate, baud_rates, 10,
316 			     &qos->baud_rate.bits);
317 	sysctl_max_baud_rate = index_value(i, baud_rates);
318 
319 	/* Set configured max disc time */
320 	i = value_lower_bits(sysctl_max_noreply_time, link_disc_times, 8,
321 			     &qos->link_disc_time.bits);
322 	sysctl_max_noreply_time = index_value(i, link_disc_times);
323 
324 	/* LSB is first byte, MSB is second byte */
325 	qos->baud_rate.bits    &= 0x03ff;
326 
327 	qos->window_size.bits     = 0x7f;
328 	qos->min_turn_time.bits   = 0xff;
329 	qos->max_turn_time.bits   = 0x0f;
330 	qos->data_size.bits       = 0x3f;
331 	qos->link_disc_time.bits &= 0xff;
332 	qos->additional_bofs.bits = 0xff;
333 }
334 EXPORT_SYMBOL(irda_init_max_qos_capabilies);
335 
336 /*
337  * Function irlap_adjust_qos_settings (qos)
338  *
339  *     Adjust QoS settings in case some values are not possible to use because
340  *     of other settings
341  */
irlap_adjust_qos_settings(struct qos_info * qos)342 static void irlap_adjust_qos_settings(struct qos_info *qos)
343 {
344 	__u32 line_capacity;
345 	int index;
346 
347 	IRDA_DEBUG(2, "%s()\n", __func__);
348 
349 	/*
350 	 * Make sure the mintt is sensible.
351 	 * Main culprit : Ericsson T39. - Jean II
352 	 */
353 	if (sysctl_min_tx_turn_time > qos->min_turn_time.value) {
354 		int i;
355 
356 		IRDA_WARNING("%s(), Detected buggy peer, adjust mtt to %dus!\n",
357 			 __func__, sysctl_min_tx_turn_time);
358 
359 		/* We don't really need bits, but easier this way */
360 		i = value_highest_bit(sysctl_min_tx_turn_time, min_turn_times,
361 				      8, &qos->min_turn_time.bits);
362 		sysctl_min_tx_turn_time = index_value(i, min_turn_times);
363 		qos->min_turn_time.value = sysctl_min_tx_turn_time;
364 	}
365 
366 	/*
367 	 * Not allowed to use a max turn time less than 500 ms if the baudrate
368 	 * is less than 115200
369 	 */
370 	if ((qos->baud_rate.value < 115200) &&
371 	    (qos->max_turn_time.value < 500))
372 	{
373 		IRDA_DEBUG(0,
374 			   "%s(), adjusting max turn time from %d to 500 ms\n",
375 			   __func__, qos->max_turn_time.value);
376 		qos->max_turn_time.value = 500;
377 	}
378 
379 	/*
380 	 * The data size must be adjusted according to the baud rate and max
381 	 * turn time
382 	 */
383 	index = value_index(qos->data_size.value, data_sizes, 6);
384 	line_capacity = irlap_max_line_capacity(qos->baud_rate.value,
385 						qos->max_turn_time.value);
386 
387 #ifdef CONFIG_IRDA_DYNAMIC_WINDOW
388 	while ((qos->data_size.value > line_capacity) && (index > 0)) {
389 		qos->data_size.value = data_sizes[index--];
390 		IRDA_DEBUG(2, "%s(), reducing data size to %d\n",
391 			   __func__, qos->data_size.value);
392 	}
393 #else /* Use method described in section 6.6.11 of IrLAP */
394 	while (irlap_requested_line_capacity(qos) > line_capacity) {
395 		IRDA_ASSERT(index != 0, return;);
396 
397 		/* Must be able to send at least one frame */
398 		if (qos->window_size.value > 1) {
399 			qos->window_size.value--;
400 			IRDA_DEBUG(2, "%s(), reducing window size to %d\n",
401 				   __func__, qos->window_size.value);
402 		} else if (index > 1) {
403 			qos->data_size.value = data_sizes[index--];
404 			IRDA_DEBUG(2, "%s(), reducing data size to %d\n",
405 				   __func__, qos->data_size.value);
406 		} else {
407 			IRDA_WARNING("%s(), nothing more we can do!\n",
408 				     __func__);
409 		}
410 	}
411 #endif /* CONFIG_IRDA_DYNAMIC_WINDOW */
412 	/*
413 	 * Fix tx data size according to user limits - Jean II
414 	 */
415 	if (qos->data_size.value > sysctl_max_tx_data_size)
416 		/* Allow non discrete adjustement to avoid losing capacity */
417 		qos->data_size.value = sysctl_max_tx_data_size;
418 	/*
419 	 * Override Tx window if user request it. - Jean II
420 	 */
421 	if (qos->window_size.value > sysctl_max_tx_window)
422 		qos->window_size.value = sysctl_max_tx_window;
423 }
424 
425 /*
426  * Function irlap_negotiate (qos_device, qos_session, skb)
427  *
428  *    Negotiate QoS values, not really that much negotiation :-)
429  *    We just set the QoS capabilities for the peer station
430  *
431  */
irlap_qos_negotiate(struct irlap_cb * self,struct sk_buff * skb)432 int irlap_qos_negotiate(struct irlap_cb *self, struct sk_buff *skb)
433 {
434 	int ret;
435 
436 	ret = irda_param_extract_all(self, skb->data, skb->len,
437 				     &irlap_param_info);
438 
439 	/* Convert the negotiated bits to values */
440 	irda_qos_bits_to_value(&self->qos_tx);
441 	irda_qos_bits_to_value(&self->qos_rx);
442 
443 	irlap_adjust_qos_settings(&self->qos_tx);
444 
445 	IRDA_DEBUG(2, "Setting BAUD_RATE to %d bps.\n",
446 		   self->qos_tx.baud_rate.value);
447 	IRDA_DEBUG(2, "Setting DATA_SIZE to %d bytes\n",
448 		   self->qos_tx.data_size.value);
449 	IRDA_DEBUG(2, "Setting WINDOW_SIZE to %d\n",
450 		   self->qos_tx.window_size.value);
451 	IRDA_DEBUG(2, "Setting XBOFS to %d\n",
452 		   self->qos_tx.additional_bofs.value);
453 	IRDA_DEBUG(2, "Setting MAX_TURN_TIME to %d ms.\n",
454 		   self->qos_tx.max_turn_time.value);
455 	IRDA_DEBUG(2, "Setting MIN_TURN_TIME to %d usecs.\n",
456 		   self->qos_tx.min_turn_time.value);
457 	IRDA_DEBUG(2, "Setting LINK_DISC to %d secs.\n",
458 		   self->qos_tx.link_disc_time.value);
459 	return ret;
460 }
461 
462 /*
463  * Function irlap_insert_negotiation_params (qos, fp)
464  *
465  *    Insert QoS negotiaion pararameters into frame
466  *
467  */
irlap_insert_qos_negotiation_params(struct irlap_cb * self,struct sk_buff * skb)468 int irlap_insert_qos_negotiation_params(struct irlap_cb *self,
469 					struct sk_buff *skb)
470 {
471 	int ret;
472 
473 	/* Insert data rate */
474 	ret = irda_param_insert(self, PI_BAUD_RATE, skb_tail_pointer(skb),
475 				skb_tailroom(skb), &irlap_param_info);
476 	if (ret < 0)
477 		return ret;
478 	skb_put(skb, ret);
479 
480 	/* Insert max turnaround time */
481 	ret = irda_param_insert(self, PI_MAX_TURN_TIME, skb_tail_pointer(skb),
482 				skb_tailroom(skb), &irlap_param_info);
483 	if (ret < 0)
484 		return ret;
485 	skb_put(skb, ret);
486 
487 	/* Insert data size */
488 	ret = irda_param_insert(self, PI_DATA_SIZE, skb_tail_pointer(skb),
489 				skb_tailroom(skb), &irlap_param_info);
490 	if (ret < 0)
491 		return ret;
492 	skb_put(skb, ret);
493 
494 	/* Insert window size */
495 	ret = irda_param_insert(self, PI_WINDOW_SIZE, skb_tail_pointer(skb),
496 				skb_tailroom(skb), &irlap_param_info);
497 	if (ret < 0)
498 		return ret;
499 	skb_put(skb, ret);
500 
501 	/* Insert additional BOFs */
502 	ret = irda_param_insert(self, PI_ADD_BOFS, skb_tail_pointer(skb),
503 				skb_tailroom(skb), &irlap_param_info);
504 	if (ret < 0)
505 		return ret;
506 	skb_put(skb, ret);
507 
508 	/* Insert minimum turnaround time */
509 	ret = irda_param_insert(self, PI_MIN_TURN_TIME, skb_tail_pointer(skb),
510 				skb_tailroom(skb), &irlap_param_info);
511 	if (ret < 0)
512 		return ret;
513 	skb_put(skb, ret);
514 
515 	/* Insert link disconnect/threshold time */
516 	ret = irda_param_insert(self, PI_LINK_DISC, skb_tail_pointer(skb),
517 				skb_tailroom(skb), &irlap_param_info);
518 	if (ret < 0)
519 		return ret;
520 	skb_put(skb, ret);
521 
522 	return 0;
523 }
524 
525 /*
526  * Function irlap_param_baud_rate (instance, param, get)
527  *
528  *    Negotiate data-rate
529  *
530  */
irlap_param_baud_rate(void * instance,irda_param_t * param,int get)531 static int irlap_param_baud_rate(void *instance, irda_param_t *param, int get)
532 {
533 	__u16 final;
534 
535 	struct irlap_cb *self = (struct irlap_cb *) instance;
536 
537 	IRDA_ASSERT(self != NULL, return -1;);
538 	IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);
539 
540 	if (get) {
541 		param->pv.i = self->qos_rx.baud_rate.bits;
542 		IRDA_DEBUG(2, "%s(), baud rate = 0x%02x\n",
543 			   __func__, param->pv.i);
544 	} else {
545 		/*
546 		 *  Stations must agree on baud rate, so calculate
547 		 *  intersection
548 		 */
549 		IRDA_DEBUG(2, "Requested BAUD_RATE: 0x%04x\n", (__u16) param->pv.i);
550 		final = (__u16) param->pv.i & self->qos_rx.baud_rate.bits;
551 
552 		IRDA_DEBUG(2, "Final BAUD_RATE: 0x%04x\n", final);
553 		self->qos_tx.baud_rate.bits = final;
554 		self->qos_rx.baud_rate.bits = final;
555 	}
556 
557 	return 0;
558 }
559 
560 /*
561  * Function irlap_param_link_disconnect (instance, param, get)
562  *
563  *    Negotiate link disconnect/threshold time.
564  *
565  */
irlap_param_link_disconnect(void * instance,irda_param_t * param,int get)566 static int irlap_param_link_disconnect(void *instance, irda_param_t *param,
567 				       int get)
568 {
569 	__u16 final;
570 
571 	struct irlap_cb *self = (struct irlap_cb *) instance;
572 
573 	IRDA_ASSERT(self != NULL, return -1;);
574 	IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);
575 
576 	if (get)
577 		param->pv.i = self->qos_rx.link_disc_time.bits;
578 	else {
579 		/*
580 		 *  Stations must agree on link disconnect/threshold
581 		 *  time.
582 		 */
583 		IRDA_DEBUG(2, "LINK_DISC: %02x\n", (__u8) param->pv.i);
584 		final = (__u8) param->pv.i & self->qos_rx.link_disc_time.bits;
585 
586 		IRDA_DEBUG(2, "Final LINK_DISC: %02x\n", final);
587 		self->qos_tx.link_disc_time.bits = final;
588 		self->qos_rx.link_disc_time.bits = final;
589 	}
590 	return 0;
591 }
592 
593 /*
594  * Function irlap_param_max_turn_time (instance, param, get)
595  *
596  *    Negotiate the maximum turnaround time. This is a type 1 parameter and
597  *    will be negotiated independently for each station
598  *
599  */
irlap_param_max_turn_time(void * instance,irda_param_t * param,int get)600 static int irlap_param_max_turn_time(void *instance, irda_param_t *param,
601 				     int get)
602 {
603 	struct irlap_cb *self = (struct irlap_cb *) instance;
604 
605 	IRDA_ASSERT(self != NULL, return -1;);
606 	IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);
607 
608 	if (get)
609 		param->pv.i = self->qos_rx.max_turn_time.bits;
610 	else
611 		self->qos_tx.max_turn_time.bits = (__u8) param->pv.i;
612 
613 	return 0;
614 }
615 
616 /*
617  * Function irlap_param_data_size (instance, param, get)
618  *
619  *    Negotiate the data size. This is a type 1 parameter and
620  *    will be negotiated independently for each station
621  *
622  */
irlap_param_data_size(void * instance,irda_param_t * param,int get)623 static int irlap_param_data_size(void *instance, irda_param_t *param, int get)
624 {
625 	struct irlap_cb *self = (struct irlap_cb *) instance;
626 
627 	IRDA_ASSERT(self != NULL, return -1;);
628 	IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);
629 
630 	if (get)
631 		param->pv.i = self->qos_rx.data_size.bits;
632 	else
633 		self->qos_tx.data_size.bits = (__u8) param->pv.i;
634 
635 	return 0;
636 }
637 
638 /*
639  * Function irlap_param_window_size (instance, param, get)
640  *
641  *    Negotiate the window size. This is a type 1 parameter and
642  *    will be negotiated independently for each station
643  *
644  */
irlap_param_window_size(void * instance,irda_param_t * param,int get)645 static int irlap_param_window_size(void *instance, irda_param_t *param,
646 				   int get)
647 {
648 	struct irlap_cb *self = (struct irlap_cb *) instance;
649 
650 	IRDA_ASSERT(self != NULL, return -1;);
651 	IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);
652 
653 	if (get)
654 		param->pv.i = self->qos_rx.window_size.bits;
655 	else
656 		self->qos_tx.window_size.bits = (__u8) param->pv.i;
657 
658 	return 0;
659 }
660 
661 /*
662  * Function irlap_param_additional_bofs (instance, param, get)
663  *
664  *    Negotiate additional BOF characters. This is a type 1 parameter and
665  *    will be negotiated independently for each station.
666  */
irlap_param_additional_bofs(void * instance,irda_param_t * param,int get)667 static int irlap_param_additional_bofs(void *instance, irda_param_t *param, int get)
668 {
669 	struct irlap_cb *self = (struct irlap_cb *) instance;
670 
671 	IRDA_ASSERT(self != NULL, return -1;);
672 	IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);
673 
674 	if (get)
675 		param->pv.i = self->qos_rx.additional_bofs.bits;
676 	else
677 		self->qos_tx.additional_bofs.bits = (__u8) param->pv.i;
678 
679 	return 0;
680 }
681 
682 /*
683  * Function irlap_param_min_turn_time (instance, param, get)
684  *
685  *    Negotiate the minimum turn around time. This is a type 1 parameter and
686  *    will be negotiated independently for each station
687  */
irlap_param_min_turn_time(void * instance,irda_param_t * param,int get)688 static int irlap_param_min_turn_time(void *instance, irda_param_t *param,
689 				     int get)
690 {
691 	struct irlap_cb *self = (struct irlap_cb *) instance;
692 
693 	IRDA_ASSERT(self != NULL, return -1;);
694 	IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);
695 
696 	if (get)
697 		param->pv.i = self->qos_rx.min_turn_time.bits;
698 	else
699 		self->qos_tx.min_turn_time.bits = (__u8) param->pv.i;
700 
701 	return 0;
702 }
703 
704 /*
705  * Function irlap_max_line_capacity (speed, max_turn_time, min_turn_time)
706  *
707  *    Calculate the maximum line capacity
708  *
709  */
irlap_max_line_capacity(__u32 speed,__u32 max_turn_time)710 __u32 irlap_max_line_capacity(__u32 speed, __u32 max_turn_time)
711 {
712 	__u32 line_capacity;
713 	int i,j;
714 
715 	IRDA_DEBUG(2, "%s(), speed=%d, max_turn_time=%d\n",
716 		   __func__, speed, max_turn_time);
717 
718 	i = value_index(speed, baud_rates, 10);
719 	j = value_index(max_turn_time, max_turn_times, 4);
720 
721 	IRDA_ASSERT(((i >=0) && (i <10)), return 0;);
722 	IRDA_ASSERT(((j >=0) && (j <4)), return 0;);
723 
724 	line_capacity = max_line_capacities[i][j];
725 
726 	IRDA_DEBUG(2, "%s(), line capacity=%d bytes\n",
727 		   __func__, line_capacity);
728 
729 	return line_capacity;
730 }
731 
732 #ifndef CONFIG_IRDA_DYNAMIC_WINDOW
irlap_requested_line_capacity(struct qos_info * qos)733 static __u32 irlap_requested_line_capacity(struct qos_info *qos)
734 {
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",
743 		   __func__, line_capacity);
744 
745 	return line_capacity;
746 }
747 #endif
748 
irda_qos_bits_to_value(struct qos_info * qos)749 void irda_qos_bits_to_value(struct qos_info *qos)
750 {
751 	int index;
752 
753 	IRDA_ASSERT(qos != NULL, return;);
754 
755 	index = msb_index(qos->baud_rate.bits);
756 	qos->baud_rate.value = baud_rates[index];
757 
758 	index = msb_index(qos->data_size.bits);
759 	qos->data_size.value = data_sizes[index];
760 
761 	index = msb_index(qos->window_size.bits);
762 	qos->window_size.value = index+1;
763 
764 	index = msb_index(qos->min_turn_time.bits);
765 	qos->min_turn_time.value = min_turn_times[index];
766 
767 	index = msb_index(qos->max_turn_time.bits);
768 	qos->max_turn_time.value = max_turn_times[index];
769 
770 	index = msb_index(qos->link_disc_time.bits);
771 	qos->link_disc_time.value = link_disc_times[index];
772 
773 	index = msb_index(qos->additional_bofs.bits);
774 	qos->additional_bofs.value = add_bofs[index];
775 }
776 EXPORT_SYMBOL(irda_qos_bits_to_value);
777