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