1 /*
2  * NXP Wireless LAN device driver: Channel, Frequence and Power
3  *
4  * Copyright 2011-2020 NXP
5  *
6  * This software file (the "File") is distributed by NXP
7  * under the terms of the GNU General Public License Version 2, June 1991
8  * (the "License").  You may use, redistribute and/or modify this File in
9  * accordance with the terms and conditions of the License, a copy of which
10  * is available by writing to the Free Software Foundation, Inc.,
11  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA or on the
12  * worldwide web at http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt.
13  *
14  * THE FILE IS DISTRIBUTED AS-IS, WITHOUT WARRANTY OF ANY KIND, AND THE
15  * IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE
16  * ARE EXPRESSLY DISCLAIMED.  The License provides additional details about
17  * this warranty disclaimer.
18  */
19 
20 #include "decl.h"
21 #include "ioctl.h"
22 #include "util.h"
23 #include "fw.h"
24 #include "main.h"
25 #include "cfg80211.h"
26 
27 /* 100mW */
28 #define MWIFIEX_TX_PWR_DEFAULT     20
29 /* 100mW */
30 #define MWIFIEX_TX_PWR_US_DEFAULT      20
31 /* 50mW */
32 #define MWIFIEX_TX_PWR_JP_DEFAULT      16
33 /* 100mW */
34 #define MWIFIEX_TX_PWR_FR_100MW        20
35 /* 10mW */
36 #define MWIFIEX_TX_PWR_FR_10MW         10
37 /* 100mW */
38 #define MWIFIEX_TX_PWR_EMEA_DEFAULT    20
39 
40 static u8 adhoc_rates_b[B_SUPPORTED_RATES] = { 0x82, 0x84, 0x8b, 0x96, 0 };
41 
42 static u8 adhoc_rates_g[G_SUPPORTED_RATES] = { 0x8c, 0x12, 0x98, 0x24,
43 					       0xb0, 0x48, 0x60, 0x6c, 0 };
44 
45 static u8 adhoc_rates_bg[BG_SUPPORTED_RATES] = { 0x82, 0x84, 0x8b, 0x96,
46 						 0x0c, 0x12, 0x18, 0x24,
47 						 0x30, 0x48, 0x60, 0x6c, 0 };
48 
49 static u8 adhoc_rates_a[A_SUPPORTED_RATES] = { 0x8c, 0x12, 0x98, 0x24,
50 					       0xb0, 0x48, 0x60, 0x6c, 0 };
51 static u8 supported_rates_a[A_SUPPORTED_RATES] = { 0x0c, 0x12, 0x18, 0x24,
52 					0xb0, 0x48, 0x60, 0x6c, 0 };
53 static u16 mwifiex_data_rates[MWIFIEX_SUPPORTED_RATES_EXT] = { 0x02, 0x04,
54 					0x0B, 0x16, 0x00, 0x0C, 0x12, 0x18,
55 					0x24, 0x30, 0x48, 0x60, 0x6C, 0x90,
56 					0x0D, 0x1A, 0x27, 0x34, 0x4E, 0x68,
57 					0x75, 0x82, 0x0C, 0x1B, 0x36, 0x51,
58 					0x6C, 0xA2, 0xD8, 0xF3, 0x10E, 0x00 };
59 
60 static u8 supported_rates_b[B_SUPPORTED_RATES] = { 0x02, 0x04, 0x0b, 0x16, 0 };
61 
62 static u8 supported_rates_g[G_SUPPORTED_RATES] = { 0x0c, 0x12, 0x18, 0x24,
63 					0x30, 0x48, 0x60, 0x6c, 0 };
64 
65 static u8 supported_rates_bg[BG_SUPPORTED_RATES] = { 0x02, 0x04, 0x0b, 0x0c,
66 					0x12, 0x16, 0x18, 0x24, 0x30, 0x48,
67 					0x60, 0x6c, 0 };
68 
69 u16 region_code_index[MWIFIEX_MAX_REGION_CODE] = { 0x00, 0x10, 0x20, 0x30,
70 						0x31, 0x32, 0x40, 0x41, 0x50 };
71 
72 static u8 supported_rates_n[N_SUPPORTED_RATES] = { 0x02, 0x04, 0 };
73 
74 /* For every mcs_rate line, the first 8 bytes are for stream 1x1,
75  * and all 16 bytes are for stream 2x2.
76  */
77 static const u16 mcs_rate[4][16] = {
78 	/* LGI 40M */
79 	{ 0x1b, 0x36, 0x51, 0x6c, 0xa2, 0xd8, 0xf3, 0x10e,
80 	  0x36, 0x6c, 0xa2, 0xd8, 0x144, 0x1b0, 0x1e6, 0x21c },
81 
82 	/* SGI 40M */
83 	{ 0x1e, 0x3c, 0x5a, 0x78, 0xb4, 0xf0, 0x10e, 0x12c,
84 	  0x3c, 0x78, 0xb4, 0xf0, 0x168, 0x1e0, 0x21c, 0x258 },
85 
86 	/* LGI 20M */
87 	{ 0x0d, 0x1a, 0x27, 0x34, 0x4e, 0x68, 0x75, 0x82,
88 	  0x1a, 0x34, 0x4e, 0x68, 0x9c, 0xd0, 0xea, 0x104 },
89 
90 	/* SGI 20M */
91 	{ 0x0e, 0x1c, 0x2b, 0x39, 0x56, 0x73, 0x82, 0x90,
92 	  0x1c, 0x39, 0x56, 0x73, 0xad, 0xe7, 0x104, 0x120 }
93 };
94 
95 /* AC rates */
96 static const u16 ac_mcs_rate_nss1[8][10] = {
97 	/* LG 160M */
98 	{ 0x75, 0xEA, 0x15F, 0x1D4, 0x2BE, 0x3A8, 0x41D,
99 	  0x492, 0x57C, 0x618 },
100 
101 	/* SG 160M */
102 	{ 0x82, 0x104, 0x186, 0x208, 0x30C, 0x410, 0x492,
103 	  0x514, 0x618, 0x6C6 },
104 
105 	/* LG 80M */
106 	{ 0x3B, 0x75, 0xB0, 0xEA, 0x15F, 0x1D4, 0x20F,
107 	  0x249, 0x2BE, 0x30C },
108 
109 	/* SG 80M */
110 	{ 0x41, 0x82, 0xC3, 0x104, 0x186, 0x208, 0x249,
111 	  0x28A, 0x30C, 0x363 },
112 
113 	/* LG 40M */
114 	{ 0x1B, 0x36, 0x51, 0x6C, 0xA2, 0xD8, 0xF3,
115 	  0x10E, 0x144, 0x168 },
116 
117 	/* SG 40M */
118 	{ 0x1E, 0x3C, 0x5A, 0x78, 0xB4, 0xF0, 0x10E,
119 	  0x12C, 0x168, 0x190 },
120 
121 	/* LG 20M */
122 	{ 0xD, 0x1A, 0x27, 0x34, 0x4E, 0x68, 0x75, 0x82, 0x9C, 0x00 },
123 
124 	/* SG 20M */
125 	{ 0xF, 0x1D, 0x2C, 0x3A, 0x57, 0x74, 0x82, 0x91, 0xAE, 0x00 },
126 };
127 
128 /* NSS2 note: the value in the table is 2 multiplier of the actual rate */
129 static const u16 ac_mcs_rate_nss2[8][10] = {
130 	/* LG 160M */
131 	{ 0xEA, 0x1D4, 0x2BE, 0x3A8, 0x57C, 0x750, 0x83A,
132 	  0x924, 0xAF8, 0xC30 },
133 
134 	/* SG 160M */
135 	{ 0x104, 0x208, 0x30C, 0x410, 0x618, 0x820, 0x924,
136 	  0xA28, 0xC30, 0xD8B },
137 
138 	/* LG 80M */
139 	{ 0x75, 0xEA, 0x15F, 0x1D4, 0x2BE, 0x3A8, 0x41D,
140 	  0x492, 0x57C, 0x618 },
141 
142 	/* SG 80M */
143 	{ 0x82, 0x104, 0x186, 0x208, 0x30C, 0x410, 0x492,
144 	  0x514, 0x618, 0x6C6 },
145 
146 	/* LG 40M */
147 	{ 0x36, 0x6C, 0xA2, 0xD8, 0x144, 0x1B0, 0x1E6,
148 	  0x21C, 0x288, 0x2D0 },
149 
150 	/* SG 40M */
151 	{ 0x3C, 0x78, 0xB4, 0xF0, 0x168, 0x1E0, 0x21C,
152 	  0x258, 0x2D0, 0x320 },
153 
154 	/* LG 20M */
155 	{ 0x1A, 0x34, 0x4A, 0x68, 0x9C, 0xD0, 0xEA, 0x104,
156 	  0x138, 0x00 },
157 
158 	/* SG 20M */
159 	{ 0x1D, 0x3A, 0x57, 0x74, 0xAE, 0xE6, 0x104, 0x121,
160 	  0x15B, 0x00 },
161 };
162 
163 struct region_code_mapping {
164 	u8 code;
165 	u8 region[IEEE80211_COUNTRY_STRING_LEN];
166 };
167 
168 static struct region_code_mapping region_code_mapping_t[] = {
169 	{ 0x10, "US " }, /* US FCC */
170 	{ 0x20, "CA " }, /* IC Canada */
171 	{ 0x30, "FR " }, /* France */
172 	{ 0x31, "ES " }, /* Spain */
173 	{ 0x32, "FR " }, /* France */
174 	{ 0x40, "JP " }, /* Japan */
175 	{ 0x41, "JP " }, /* Japan */
176 	{ 0x50, "CN " }, /* China */
177 };
178 
179 /* This function converts integer code to region string */
mwifiex_11d_code_2_region(u8 code)180 u8 *mwifiex_11d_code_2_region(u8 code)
181 {
182 	u8 i;
183 
184 	/* Look for code in mapping table */
185 	for (i = 0; i < ARRAY_SIZE(region_code_mapping_t); i++)
186 		if (region_code_mapping_t[i].code == code)
187 			return region_code_mapping_t[i].region;
188 
189 	return NULL;
190 }
191 
192 /*
193  * This function maps an index in supported rates table into
194  * the corresponding data rate.
195  */
mwifiex_index_to_acs_data_rate(struct mwifiex_private * priv,u8 index,u8 ht_info)196 u32 mwifiex_index_to_acs_data_rate(struct mwifiex_private *priv,
197 				   u8 index, u8 ht_info)
198 {
199 	u32 rate = 0;
200 	u8 mcs_index = 0;
201 	u8 bw = 0;
202 	u8 gi = 0;
203 
204 	if ((ht_info & 0x3) == MWIFIEX_RATE_FORMAT_VHT) {
205 		mcs_index = min(index & 0xF, 9);
206 
207 		/* 20M: bw=0, 40M: bw=1, 80M: bw=2, 160M: bw=3 */
208 		bw = (ht_info & 0xC) >> 2;
209 
210 		/* LGI: gi =0, SGI: gi = 1 */
211 		gi = (ht_info & 0x10) >> 4;
212 
213 		if ((index >> 4) == 1)	/* NSS = 2 */
214 			rate = ac_mcs_rate_nss2[2 * (3 - bw) + gi][mcs_index];
215 		else			/* NSS = 1 */
216 			rate = ac_mcs_rate_nss1[2 * (3 - bw) + gi][mcs_index];
217 	} else if ((ht_info & 0x3) == MWIFIEX_RATE_FORMAT_HT) {
218 		/* 20M: bw=0, 40M: bw=1 */
219 		bw = (ht_info & 0xC) >> 2;
220 
221 		/* LGI: gi =0, SGI: gi = 1 */
222 		gi = (ht_info & 0x10) >> 4;
223 
224 		if (index == MWIFIEX_RATE_BITMAP_MCS0) {
225 			if (gi == 1)
226 				rate = 0x0D;    /* MCS 32 SGI rate */
227 			else
228 				rate = 0x0C;    /* MCS 32 LGI rate */
229 		} else if (index < 16) {
230 			if ((bw == 1) || (bw == 0))
231 				rate = mcs_rate[2 * (1 - bw) + gi][index];
232 			else
233 				rate = mwifiex_data_rates[0];
234 		} else {
235 			rate = mwifiex_data_rates[0];
236 		}
237 	} else {
238 		/* 11n non-HT rates */
239 		if (index >= MWIFIEX_SUPPORTED_RATES_EXT)
240 			index = 0;
241 		rate = mwifiex_data_rates[index];
242 	}
243 
244 	return rate;
245 }
246 
247 /* This function maps an index in supported rates table into
248  * the corresponding data rate.
249  */
mwifiex_index_to_data_rate(struct mwifiex_private * priv,u8 index,u8 ht_info)250 u32 mwifiex_index_to_data_rate(struct mwifiex_private *priv,
251 			       u8 index, u8 ht_info)
252 {
253 	u32 mcs_num_supp =
254 		(priv->adapter->user_dev_mcs_support == HT_STREAM_2X2) ? 16 : 8;
255 	u32 rate;
256 
257 	if (priv->adapter->is_hw_11ac_capable)
258 		return mwifiex_index_to_acs_data_rate(priv, index, ht_info);
259 
260 	if (ht_info & BIT(0)) {
261 		if (index == MWIFIEX_RATE_BITMAP_MCS0) {
262 			if (ht_info & BIT(2))
263 				rate = 0x0D;	/* MCS 32 SGI rate */
264 			else
265 				rate = 0x0C;	/* MCS 32 LGI rate */
266 		} else if (index < mcs_num_supp) {
267 			if (ht_info & BIT(1)) {
268 				if (ht_info & BIT(2))
269 					/* SGI, 40M */
270 					rate = mcs_rate[1][index];
271 				else
272 					/* LGI, 40M */
273 					rate = mcs_rate[0][index];
274 			} else {
275 				if (ht_info & BIT(2))
276 					/* SGI, 20M */
277 					rate = mcs_rate[3][index];
278 				else
279 					/* LGI, 20M */
280 					rate = mcs_rate[2][index];
281 			}
282 		} else
283 			rate = mwifiex_data_rates[0];
284 	} else {
285 		if (index >= MWIFIEX_SUPPORTED_RATES_EXT)
286 			index = 0;
287 		rate = mwifiex_data_rates[index];
288 	}
289 	return rate;
290 }
291 
292 /*
293  * This function returns the current active data rates.
294  *
295  * The result may vary depending upon connection status.
296  */
mwifiex_get_active_data_rates(struct mwifiex_private * priv,u8 * rates)297 u32 mwifiex_get_active_data_rates(struct mwifiex_private *priv, u8 *rates)
298 {
299 	if (!priv->media_connected)
300 		return mwifiex_get_supported_rates(priv, rates);
301 	else
302 		return mwifiex_copy_rates(rates, 0,
303 					  priv->curr_bss_params.data_rates,
304 					  priv->curr_bss_params.num_of_rates);
305 }
306 
307 /*
308  * This function locates the Channel-Frequency-Power triplet based upon
309  * band and channel/frequency parameters.
310  */
311 struct mwifiex_chan_freq_power *
mwifiex_get_cfp(struct mwifiex_private * priv,u8 band,u16 channel,u32 freq)312 mwifiex_get_cfp(struct mwifiex_private *priv, u8 band, u16 channel, u32 freq)
313 {
314 	struct mwifiex_chan_freq_power *cfp = NULL;
315 	struct ieee80211_supported_band *sband;
316 	struct ieee80211_channel *ch = NULL;
317 	int i;
318 
319 	if (!channel && !freq)
320 		return cfp;
321 
322 	if (mwifiex_band_to_radio_type(band) == HostCmd_SCAN_RADIO_TYPE_BG)
323 		sband = priv->wdev.wiphy->bands[NL80211_BAND_2GHZ];
324 	else
325 		sband = priv->wdev.wiphy->bands[NL80211_BAND_5GHZ];
326 
327 	if (!sband) {
328 		mwifiex_dbg(priv->adapter, ERROR,
329 			    "%s: cannot find cfp by band %d\n",
330 			    __func__, band);
331 		return cfp;
332 	}
333 
334 	for (i = 0; i < sband->n_channels; i++) {
335 		ch = &sband->channels[i];
336 
337 		if (ch->flags & IEEE80211_CHAN_DISABLED)
338 			continue;
339 
340 		if (freq) {
341 			if (ch->center_freq == freq)
342 				break;
343 		} else {
344 			/* find by valid channel*/
345 			if (ch->hw_value == channel ||
346 			    channel == FIRST_VALID_CHANNEL)
347 				break;
348 		}
349 	}
350 	if (i == sband->n_channels) {
351 		mwifiex_dbg(priv->adapter, WARN,
352 			    "%s: cannot find cfp by band %d\t"
353 			    "& channel=%d freq=%d\n",
354 			    __func__, band, channel, freq);
355 	} else {
356 		if (!ch)
357 			return cfp;
358 
359 		priv->cfp.channel = ch->hw_value;
360 		priv->cfp.freq = ch->center_freq;
361 		priv->cfp.max_tx_power = ch->max_power;
362 		cfp = &priv->cfp;
363 	}
364 
365 	return cfp;
366 }
367 
368 /*
369  * This function checks if the data rate is set to auto.
370  */
371 u8
mwifiex_is_rate_auto(struct mwifiex_private * priv)372 mwifiex_is_rate_auto(struct mwifiex_private *priv)
373 {
374 	u32 i;
375 	int rate_num = 0;
376 
377 	for (i = 0; i < ARRAY_SIZE(priv->bitmap_rates); i++)
378 		if (priv->bitmap_rates[i])
379 			rate_num++;
380 
381 	if (rate_num > 1)
382 		return true;
383 	else
384 		return false;
385 }
386 
387 /* This function gets the supported data rates from bitmask inside
388  * cfg80211_scan_request.
389  */
mwifiex_get_rates_from_cfg80211(struct mwifiex_private * priv,u8 * rates,u8 radio_type)390 u32 mwifiex_get_rates_from_cfg80211(struct mwifiex_private *priv,
391 				    u8 *rates, u8 radio_type)
392 {
393 	struct wiphy *wiphy = priv->adapter->wiphy;
394 	struct cfg80211_scan_request *request = priv->scan_request;
395 	u32 num_rates, rate_mask;
396 	struct ieee80211_supported_band *sband;
397 	int i;
398 
399 	if (radio_type) {
400 		sband = wiphy->bands[NL80211_BAND_5GHZ];
401 		if (WARN_ON_ONCE(!sband))
402 			return 0;
403 		rate_mask = request->rates[NL80211_BAND_5GHZ];
404 	} else {
405 		sband = wiphy->bands[NL80211_BAND_2GHZ];
406 		if (WARN_ON_ONCE(!sband))
407 			return 0;
408 		rate_mask = request->rates[NL80211_BAND_2GHZ];
409 	}
410 
411 	num_rates = 0;
412 	for (i = 0; i < sband->n_bitrates; i++) {
413 		if ((BIT(i) & rate_mask) == 0)
414 			continue; /* skip rate */
415 		rates[num_rates++] = (u8)(sband->bitrates[i].bitrate / 5);
416 	}
417 
418 	return num_rates;
419 }
420 
421 /* This function gets the supported data rates. The function works in
422  * both Ad-Hoc and infra mode by printing the band and returning the
423  * data rates.
424  */
mwifiex_get_supported_rates(struct mwifiex_private * priv,u8 * rates)425 u32 mwifiex_get_supported_rates(struct mwifiex_private *priv, u8 *rates)
426 {
427 	u32 k = 0;
428 	struct mwifiex_adapter *adapter = priv->adapter;
429 
430 	if (priv->bss_mode == NL80211_IFTYPE_STATION ||
431 	    priv->bss_mode == NL80211_IFTYPE_P2P_CLIENT) {
432 		switch (adapter->config_bands) {
433 		case BAND_B:
434 			mwifiex_dbg(adapter, INFO, "info: infra band=%d\t"
435 				    "supported_rates_b\n",
436 				    adapter->config_bands);
437 			k = mwifiex_copy_rates(rates, k, supported_rates_b,
438 					       sizeof(supported_rates_b));
439 			break;
440 		case BAND_G:
441 		case BAND_G | BAND_GN:
442 			mwifiex_dbg(adapter, INFO, "info: infra band=%d\t"
443 				    "supported_rates_g\n",
444 				    adapter->config_bands);
445 			k = mwifiex_copy_rates(rates, k, supported_rates_g,
446 					       sizeof(supported_rates_g));
447 			break;
448 		case BAND_B | BAND_G:
449 		case BAND_A | BAND_B | BAND_G:
450 		case BAND_A | BAND_B:
451 		case BAND_A | BAND_B | BAND_G | BAND_GN | BAND_AN:
452 		case BAND_A | BAND_B | BAND_G | BAND_GN | BAND_AN | BAND_AAC:
453 		case BAND_B | BAND_G | BAND_GN:
454 			mwifiex_dbg(adapter, INFO, "info: infra band=%d\t"
455 				    "supported_rates_bg\n",
456 				    adapter->config_bands);
457 			k = mwifiex_copy_rates(rates, k, supported_rates_bg,
458 					       sizeof(supported_rates_bg));
459 			break;
460 		case BAND_A:
461 		case BAND_A | BAND_G:
462 			mwifiex_dbg(adapter, INFO, "info: infra band=%d\t"
463 				    "supported_rates_a\n",
464 				    adapter->config_bands);
465 			k = mwifiex_copy_rates(rates, k, supported_rates_a,
466 					       sizeof(supported_rates_a));
467 			break;
468 		case BAND_AN:
469 		case BAND_A | BAND_AN:
470 		case BAND_A | BAND_AN | BAND_AAC:
471 		case BAND_A | BAND_G | BAND_AN | BAND_GN:
472 		case BAND_A | BAND_G | BAND_AN | BAND_GN | BAND_AAC:
473 			mwifiex_dbg(adapter, INFO, "info: infra band=%d\t"
474 				    "supported_rates_a\n",
475 				    adapter->config_bands);
476 			k = mwifiex_copy_rates(rates, k, supported_rates_a,
477 					       sizeof(supported_rates_a));
478 			break;
479 		case BAND_GN:
480 			mwifiex_dbg(adapter, INFO, "info: infra band=%d\t"
481 				    "supported_rates_n\n",
482 				    adapter->config_bands);
483 			k = mwifiex_copy_rates(rates, k, supported_rates_n,
484 					       sizeof(supported_rates_n));
485 			break;
486 		}
487 	} else {
488 		/* Ad-hoc mode */
489 		switch (adapter->adhoc_start_band) {
490 		case BAND_B:
491 			mwifiex_dbg(adapter, INFO, "info: adhoc B\n");
492 			k = mwifiex_copy_rates(rates, k, adhoc_rates_b,
493 					       sizeof(adhoc_rates_b));
494 			break;
495 		case BAND_G:
496 		case BAND_G | BAND_GN:
497 			mwifiex_dbg(adapter, INFO, "info: adhoc G only\n");
498 			k = mwifiex_copy_rates(rates, k, adhoc_rates_g,
499 					       sizeof(adhoc_rates_g));
500 			break;
501 		case BAND_B | BAND_G:
502 		case BAND_B | BAND_G | BAND_GN:
503 			mwifiex_dbg(adapter, INFO, "info: adhoc BG\n");
504 			k = mwifiex_copy_rates(rates, k, adhoc_rates_bg,
505 					       sizeof(adhoc_rates_bg));
506 			break;
507 		case BAND_A:
508 		case BAND_A | BAND_AN:
509 			mwifiex_dbg(adapter, INFO, "info: adhoc A\n");
510 			k = mwifiex_copy_rates(rates, k, adhoc_rates_a,
511 					       sizeof(adhoc_rates_a));
512 			break;
513 		}
514 	}
515 
516 	return k;
517 }
518 
mwifiex_adjust_data_rate(struct mwifiex_private * priv,u8 rx_rate,u8 rate_info)519 u8 mwifiex_adjust_data_rate(struct mwifiex_private *priv,
520 			    u8 rx_rate, u8 rate_info)
521 {
522 	u8 rate_index = 0;
523 
524 	/* HT40 */
525 	if ((rate_info & BIT(0)) && (rate_info & BIT(1)))
526 		rate_index = MWIFIEX_RATE_INDEX_MCS0 +
527 			     MWIFIEX_BW20_MCS_NUM + rx_rate;
528 	else if (rate_info & BIT(0)) /* HT20 */
529 		rate_index = MWIFIEX_RATE_INDEX_MCS0 + rx_rate;
530 	else
531 		rate_index = (rx_rate > MWIFIEX_RATE_INDEX_OFDM0) ?
532 			      rx_rate - 1 : rx_rate;
533 
534 	if (rate_index >= MWIFIEX_MAX_AC_RX_RATES)
535 		rate_index = MWIFIEX_MAX_AC_RX_RATES - 1;
536 
537 	return rate_index;
538 }
539