1 /*
2  * Copyright (c) 2013 Qualcomm Atheros, Inc.
3  *
4  * Permission to use, copy, modify, and/or distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include <linux/relay.h>
18 #include <linux/random.h>
19 #include "ath9k.h"
20 
21 static s8 fix_rssi_inv_only(u8 rssi_val)
22 {
23 	if (rssi_val == 128)
24 		rssi_val = 0;
25 	return (s8) rssi_val;
26 }
27 
28 static void ath_debug_send_fft_sample(struct ath_spec_scan_priv *spec_priv,
29 				      struct fft_sample_tlv *fft_sample_tlv)
30 {
31 	int length;
32 	if (!spec_priv->rfs_chan_spec_scan)
33 		return;
34 
35 	length = __be16_to_cpu(fft_sample_tlv->length) +
36 		 sizeof(*fft_sample_tlv);
37 	relay_write(spec_priv->rfs_chan_spec_scan, fft_sample_tlv, length);
38 }
39 
40 typedef int (ath_cmn_fft_idx_validator) (u8 *sample_end, int bytes_read);
41 
42 static int
43 ath_cmn_max_idx_verify_ht20_fft(u8 *sample_end, int bytes_read)
44 {
45 	struct ath_ht20_mag_info *mag_info;
46 	u8 *sample;
47 	u16 max_magnitude;
48 	u8 max_index;
49 	u8 max_exp;
50 
51 	/* Sanity check so that we don't read outside the read
52 	 * buffer
53 	 */
54 	if (bytes_read < SPECTRAL_HT20_SAMPLE_LEN - 1)
55 		return -1;
56 
57 	mag_info = (struct ath_ht20_mag_info *) (sample_end -
58 				sizeof(struct ath_ht20_mag_info) + 1);
59 
60 	sample = sample_end - SPECTRAL_HT20_SAMPLE_LEN + 1;
61 
62 	max_index = spectral_max_index(mag_info->all_bins,
63 				       SPECTRAL_HT20_NUM_BINS);
64 	max_magnitude = spectral_max_magnitude(mag_info->all_bins);
65 
66 	max_exp = mag_info->max_exp & 0xf;
67 
68 	/* Don't try to read something outside the read buffer
69 	 * in case of a missing byte (so bins[0] will be outside
70 	 * the read buffer)
71 	 */
72 	if (bytes_read < SPECTRAL_HT20_SAMPLE_LEN && max_index < 1)
73 		return -1;
74 
75 	if (sample[max_index] != (max_magnitude >> max_exp))
76 		return -1;
77 	else
78 		return 0;
79 }
80 
81 static int
82 ath_cmn_max_idx_verify_ht20_40_fft(u8 *sample_end, int bytes_read)
83 {
84 	struct ath_ht20_40_mag_info *mag_info;
85 	u8 *sample;
86 	u16 lower_mag, upper_mag;
87 	u8 lower_max_index, upper_max_index;
88 	u8 max_exp;
89 	int dc_pos = SPECTRAL_HT20_40_NUM_BINS / 2;
90 
91 	/* Sanity check so that we don't read outside the read
92 	 * buffer
93 	 */
94 	if (bytes_read < SPECTRAL_HT20_40_SAMPLE_LEN - 1)
95 		return -1;
96 
97 	mag_info = (struct ath_ht20_40_mag_info *) (sample_end -
98 				sizeof(struct ath_ht20_40_mag_info) + 1);
99 
100 	sample = sample_end - SPECTRAL_HT20_40_SAMPLE_LEN + 1;
101 
102 	lower_mag = spectral_max_magnitude(mag_info->lower_bins);
103 	lower_max_index = spectral_max_index(mag_info->lower_bins,
104 					     SPECTRAL_HT20_40_NUM_BINS);
105 
106 	upper_mag = spectral_max_magnitude(mag_info->upper_bins);
107 	upper_max_index = spectral_max_index(mag_info->upper_bins,
108 					     SPECTRAL_HT20_40_NUM_BINS);
109 
110 	max_exp = mag_info->max_exp & 0xf;
111 
112 	/* Don't try to read something outside the read buffer
113 	 * in case of a missing byte (so bins[0] will be outside
114 	 * the read buffer)
115 	 */
116 	if (bytes_read < SPECTRAL_HT20_40_SAMPLE_LEN &&
117 	   ((upper_max_index < 1) || (lower_max_index < 1)))
118 		return -1;
119 
120 	/* Some time hardware messes up the index and adds
121 	 * the index of the middle point (dc_pos). Try to fix it.
122 	 */
123 	if ((upper_max_index - dc_pos > 0) &&
124 	   (sample[upper_max_index] == (upper_mag >> max_exp)))
125 		upper_max_index -= dc_pos;
126 
127 	if ((lower_max_index - dc_pos > 0) &&
128 	   (sample[lower_max_index - dc_pos] == (lower_mag >> max_exp)))
129 		lower_max_index -= dc_pos;
130 
131 	if ((sample[upper_max_index + dc_pos] != (upper_mag >> max_exp)) ||
132 	   (sample[lower_max_index] != (lower_mag >> max_exp)))
133 		return -1;
134 	else
135 		return 0;
136 }
137 
138 typedef int (ath_cmn_fft_sample_handler) (struct ath_rx_status *rs,
139 			struct ath_spec_scan_priv *spec_priv,
140 			u8 *sample_buf, u64 tsf, u16 freq, int chan_type);
141 
142 static int
143 ath_cmn_process_ht20_fft(struct ath_rx_status *rs,
144 			struct ath_spec_scan_priv *spec_priv,
145 			u8 *sample_buf,
146 			u64 tsf, u16 freq, int chan_type)
147 {
148 	struct fft_sample_ht20 fft_sample_20;
149 	struct ath_common *common = ath9k_hw_common(spec_priv->ah);
150 	struct ath_hw *ah = spec_priv->ah;
151 	struct ath_ht20_mag_info *mag_info;
152 	struct fft_sample_tlv *tlv;
153 	int i = 0;
154 	int ret = 0;
155 	int dc_pos = SPECTRAL_HT20_NUM_BINS / 2;
156 	u16 magnitude, tmp_mag, length;
157 	u8 max_index, bitmap_w, max_exp;
158 
159 	length = sizeof(fft_sample_20) - sizeof(struct fft_sample_tlv);
160 	fft_sample_20.tlv.type = ATH_FFT_SAMPLE_HT20;
161 	fft_sample_20.tlv.length = __cpu_to_be16(length);
162 	fft_sample_20.freq = __cpu_to_be16(freq);
163 	fft_sample_20.rssi = fix_rssi_inv_only(rs->rs_rssi_ctl[0]);
164 	fft_sample_20.noise = ah->noise;
165 
166 	mag_info = (struct ath_ht20_mag_info *) (sample_buf +
167 					SPECTRAL_HT20_NUM_BINS);
168 
169 	magnitude = spectral_max_magnitude(mag_info->all_bins);
170 	fft_sample_20.max_magnitude = __cpu_to_be16(magnitude);
171 
172 	max_index = spectral_max_index(mag_info->all_bins,
173 					SPECTRAL_HT20_NUM_BINS);
174 	fft_sample_20.max_index = max_index;
175 
176 	bitmap_w = spectral_bitmap_weight(mag_info->all_bins);
177 	fft_sample_20.bitmap_weight = bitmap_w;
178 
179 	max_exp = mag_info->max_exp & 0xf;
180 	fft_sample_20.max_exp = max_exp;
181 
182 	fft_sample_20.tsf = __cpu_to_be64(tsf);
183 
184 	memcpy(fft_sample_20.data, sample_buf, SPECTRAL_HT20_NUM_BINS);
185 
186 	ath_dbg(common, SPECTRAL_SCAN, "FFT HT20 frame: max mag 0x%X,"
187 					"max_mag_idx %i\n",
188 					magnitude >> max_exp,
189 					max_index);
190 
191 	if (fft_sample_20.data[max_index] != (magnitude >> max_exp)) {
192 		ath_dbg(common, SPECTRAL_SCAN, "Magnitude mismatch !\n");
193 		ret = -1;
194 	}
195 
196 	/* DC value (value in the middle) is the blind spot of the spectral
197 	 * sample and invalid, interpolate it.
198 	 */
199 	fft_sample_20.data[dc_pos] = (fft_sample_20.data[dc_pos + 1] +
200 					fft_sample_20.data[dc_pos - 1]) / 2;
201 
202 	/* Check if the maximum magnitude is indeed maximum,
203 	 * also if the maximum value was at dc_pos, calculate
204 	 * a new one (since value at dc_pos is invalid).
205 	 */
206 	if (max_index == dc_pos) {
207 		tmp_mag = 0;
208 		for (i = 0; i < dc_pos; i++) {
209 			if (fft_sample_20.data[i] > tmp_mag) {
210 				tmp_mag = fft_sample_20.data[i];
211 				fft_sample_20.max_index = i;
212 			}
213 		}
214 
215 		magnitude = tmp_mag << max_exp;
216 		fft_sample_20.max_magnitude = __cpu_to_be16(magnitude);
217 
218 		ath_dbg(common, SPECTRAL_SCAN,
219 			"Calculated new lower max 0x%X at %i\n",
220 			tmp_mag, fft_sample_20.max_index);
221 	} else
222 	for (i = 0; i < SPECTRAL_HT20_NUM_BINS; i++) {
223 		if (fft_sample_20.data[i] == (magnitude >> max_exp))
224 			ath_dbg(common, SPECTRAL_SCAN,
225 				"Got max: 0x%X at index %i\n",
226 				fft_sample_20.data[i], i);
227 
228 		if (fft_sample_20.data[i] > (magnitude >> max_exp)) {
229 			ath_dbg(common, SPECTRAL_SCAN,
230 				"Got bin %i greater than max: 0x%X\n",
231 				i, fft_sample_20.data[i]);
232 			ret = -1;
233 		}
234 	}
235 
236 	if (ret < 0)
237 		return ret;
238 
239 	tlv = (struct fft_sample_tlv *)&fft_sample_20;
240 
241 	ath_debug_send_fft_sample(spec_priv, tlv);
242 
243 	return 0;
244 }
245 
246 static int
247 ath_cmn_process_ht20_40_fft(struct ath_rx_status *rs,
248 			struct ath_spec_scan_priv *spec_priv,
249 			u8 *sample_buf,
250 			u64 tsf, u16 freq, int chan_type)
251 {
252 	struct fft_sample_ht20_40 fft_sample_40;
253 	struct ath_common *common = ath9k_hw_common(spec_priv->ah);
254 	struct ath_hw *ah = spec_priv->ah;
255 	struct ath9k_hw_cal_data *caldata = ah->caldata;
256 	struct ath_ht20_40_mag_info *mag_info;
257 	struct fft_sample_tlv *tlv;
258 	int dc_pos = SPECTRAL_HT20_40_NUM_BINS / 2;
259 	int i = 0;
260 	int ret = 0;
261 	s16 ext_nf;
262 	u16 lower_mag, upper_mag, tmp_mag, length;
263 	s8 lower_rssi, upper_rssi;
264 	u8 lower_max_index, upper_max_index;
265 	u8 lower_bitmap_w, upper_bitmap_w, max_exp;
266 
267 	if (caldata)
268 		ext_nf = ath9k_hw_getchan_noise(ah, ah->curchan,
269 				caldata->nfCalHist[3].privNF);
270 	else
271 		ext_nf = ATH_DEFAULT_NOISE_FLOOR;
272 
273 	length = sizeof(fft_sample_40) - sizeof(struct fft_sample_tlv);
274 	fft_sample_40.tlv.type = ATH_FFT_SAMPLE_HT20_40;
275 	fft_sample_40.tlv.length = __cpu_to_be16(length);
276 	fft_sample_40.freq = __cpu_to_be16(freq);
277 	fft_sample_40.channel_type = chan_type;
278 
279 	if (chan_type == NL80211_CHAN_HT40PLUS) {
280 		lower_rssi = fix_rssi_inv_only(rs->rs_rssi_ctl[0]);
281 		upper_rssi = fix_rssi_inv_only(rs->rs_rssi_ext[0]);
282 
283 		fft_sample_40.lower_noise = ah->noise;
284 		fft_sample_40.upper_noise = ext_nf;
285 	} else {
286 		lower_rssi = fix_rssi_inv_only(rs->rs_rssi_ext[0]);
287 		upper_rssi = fix_rssi_inv_only(rs->rs_rssi_ctl[0]);
288 
289 		fft_sample_40.lower_noise = ext_nf;
290 		fft_sample_40.upper_noise = ah->noise;
291 	}
292 
293 	fft_sample_40.lower_rssi = lower_rssi;
294 	fft_sample_40.upper_rssi = upper_rssi;
295 
296 	mag_info = (struct ath_ht20_40_mag_info *) (sample_buf +
297 					SPECTRAL_HT20_40_NUM_BINS);
298 
299 	lower_mag = spectral_max_magnitude(mag_info->lower_bins);
300 	fft_sample_40.lower_max_magnitude = __cpu_to_be16(lower_mag);
301 
302 	upper_mag = spectral_max_magnitude(mag_info->upper_bins);
303 	fft_sample_40.upper_max_magnitude = __cpu_to_be16(upper_mag);
304 
305 	lower_max_index = spectral_max_index(mag_info->lower_bins,
306 					SPECTRAL_HT20_40_NUM_BINS);
307 	fft_sample_40.lower_max_index = lower_max_index;
308 
309 	upper_max_index = spectral_max_index(mag_info->upper_bins,
310 					SPECTRAL_HT20_40_NUM_BINS);
311 	fft_sample_40.upper_max_index = upper_max_index;
312 
313 	lower_bitmap_w = spectral_bitmap_weight(mag_info->lower_bins);
314 	fft_sample_40.lower_bitmap_weight = lower_bitmap_w;
315 
316 	upper_bitmap_w = spectral_bitmap_weight(mag_info->upper_bins);
317 	fft_sample_40.upper_bitmap_weight = upper_bitmap_w;
318 
319 	max_exp = mag_info->max_exp & 0xf;
320 	fft_sample_40.max_exp = max_exp;
321 
322 	fft_sample_40.tsf = __cpu_to_be64(tsf);
323 
324 	memcpy(fft_sample_40.data, sample_buf, SPECTRAL_HT20_40_NUM_BINS);
325 
326 	ath_dbg(common, SPECTRAL_SCAN, "FFT HT20/40 frame: lower mag 0x%X,"
327 					"lower_mag_idx %i, upper mag 0x%X,"
328 					"upper_mag_idx %i\n",
329 					lower_mag >> max_exp,
330 					lower_max_index,
331 					upper_mag >> max_exp,
332 					upper_max_index);
333 
334 	/* Some time hardware messes up the index and adds
335 	 * the index of the middle point (dc_pos). Try to fix it.
336 	 */
337 	if ((upper_max_index - dc_pos > 0) &&
338 	   (fft_sample_40.data[upper_max_index] == (upper_mag >> max_exp))) {
339 		upper_max_index -= dc_pos;
340 		fft_sample_40.upper_max_index = upper_max_index;
341 	}
342 
343 	if ((lower_max_index - dc_pos > 0) &&
344 	   (fft_sample_40.data[lower_max_index - dc_pos] ==
345 	   (lower_mag >> max_exp))) {
346 		lower_max_index -= dc_pos;
347 		fft_sample_40.lower_max_index = lower_max_index;
348 	}
349 
350 	/* Check if we got the expected magnitude values at
351 	 * the expected bins
352 	 */
353 	if ((fft_sample_40.data[upper_max_index + dc_pos]
354 	    != (upper_mag >> max_exp)) ||
355 	   (fft_sample_40.data[lower_max_index]
356 	    != (lower_mag >> max_exp))) {
357 		ath_dbg(common, SPECTRAL_SCAN, "Magnitude mismatch !\n");
358 		ret = -1;
359 	}
360 
361 	/* DC value (value in the middle) is the blind spot of the spectral
362 	 * sample and invalid, interpolate it.
363 	 */
364 	fft_sample_40.data[dc_pos] = (fft_sample_40.data[dc_pos + 1] +
365 					fft_sample_40.data[dc_pos - 1]) / 2;
366 
367 	/* Check if the maximum magnitudes are indeed maximum,
368 	 * also if the maximum value was at dc_pos, calculate
369 	 * a new one (since value at dc_pos is invalid).
370 	 */
371 	if (lower_max_index == dc_pos) {
372 		tmp_mag = 0;
373 		for (i = 0; i < dc_pos; i++) {
374 			if (fft_sample_40.data[i] > tmp_mag) {
375 				tmp_mag = fft_sample_40.data[i];
376 				fft_sample_40.lower_max_index = i;
377 			}
378 		}
379 
380 		lower_mag = tmp_mag << max_exp;
381 		fft_sample_40.lower_max_magnitude = __cpu_to_be16(lower_mag);
382 
383 		ath_dbg(common, SPECTRAL_SCAN,
384 			"Calculated new lower max 0x%X at %i\n",
385 			tmp_mag, fft_sample_40.lower_max_index);
386 	} else
387 	for (i = 0; i < dc_pos; i++) {
388 		if (fft_sample_40.data[i] == (lower_mag >> max_exp))
389 			ath_dbg(common, SPECTRAL_SCAN,
390 				"Got lower mag: 0x%X at index %i\n",
391 				fft_sample_40.data[i], i);
392 
393 		if (fft_sample_40.data[i] > (lower_mag >> max_exp)) {
394 			ath_dbg(common, SPECTRAL_SCAN,
395 				"Got lower bin %i higher than max: 0x%X\n",
396 				i, fft_sample_40.data[i]);
397 			ret = -1;
398 		}
399 	}
400 
401 	if (upper_max_index == dc_pos) {
402 		tmp_mag = 0;
403 		for (i = dc_pos; i < SPECTRAL_HT20_40_NUM_BINS; i++) {
404 			if (fft_sample_40.data[i] > tmp_mag) {
405 				tmp_mag = fft_sample_40.data[i];
406 				fft_sample_40.upper_max_index = i;
407 			}
408 		}
409 		upper_mag = tmp_mag << max_exp;
410 		fft_sample_40.upper_max_magnitude = __cpu_to_be16(upper_mag);
411 
412 		ath_dbg(common, SPECTRAL_SCAN,
413 			"Calculated new upper max 0x%X at %i\n",
414 			tmp_mag, i);
415 	} else
416 	for (i = dc_pos; i < SPECTRAL_HT20_40_NUM_BINS; i++) {
417 		if (fft_sample_40.data[i] == (upper_mag >> max_exp))
418 			ath_dbg(common, SPECTRAL_SCAN,
419 				"Got upper mag: 0x%X at index %i\n",
420 				fft_sample_40.data[i], i);
421 
422 		if (fft_sample_40.data[i] > (upper_mag >> max_exp)) {
423 			ath_dbg(common, SPECTRAL_SCAN,
424 				"Got upper bin %i higher than max: 0x%X\n",
425 				i, fft_sample_40.data[i]);
426 
427 			ret = -1;
428 		}
429 	}
430 
431 	if (ret < 0)
432 		return ret;
433 
434 	tlv = (struct fft_sample_tlv *)&fft_sample_40;
435 
436 	ath_debug_send_fft_sample(spec_priv, tlv);
437 
438 	return 0;
439 }
440 
441 static inline void
442 ath_cmn_copy_fft_frame(u8 *in, u8 *out, int sample_len, int sample_bytes)
443 {
444 	switch (sample_bytes - sample_len) {
445 	case -1:
446 		/* First byte missing */
447 		memcpy(&out[1], in,
448 		       sample_len - 1);
449 		break;
450 	case 0:
451 		/* Length correct, nothing to do. */
452 		memcpy(out, in, sample_len);
453 		break;
454 	case 1:
455 		/* MAC added 2 extra bytes AND first byte
456 		 * is missing.
457 		 */
458 		memcpy(&out[1], in, 30);
459 		out[31] = in[31];
460 		memcpy(&out[32], &in[33],
461 		       sample_len - 32);
462 		break;
463 	case 2:
464 		/* MAC added 2 extra bytes at bin 30 and 32,
465 		 * remove them.
466 		 */
467 		memcpy(out, in, 30);
468 		out[30] = in[31];
469 		memcpy(&out[31], &in[33],
470 		       sample_len - 31);
471 		break;
472 	default:
473 		break;
474 	}
475 }
476 
477 static int
478 ath_cmn_is_fft_buf_full(struct ath_spec_scan_priv *spec_priv)
479 {
480 	int i = 0;
481 	int ret = 0;
482 	struct rchan *rc = spec_priv->rfs_chan_spec_scan;
483 
484 	for_each_online_cpu(i)
485 		ret += relay_buf_full(rc->buf[i]);
486 
487 	i = num_online_cpus();
488 
489 	if (ret == i)
490 		return 1;
491 	else
492 		return 0;
493 }
494 
495 /* returns 1 if this was a spectral frame, even if not handled. */
496 int ath_cmn_process_fft(struct ath_spec_scan_priv *spec_priv, struct ieee80211_hdr *hdr,
497 		    struct ath_rx_status *rs, u64 tsf)
498 {
499 	u8 sample_buf[SPECTRAL_SAMPLE_MAX_LEN] = {0};
500 	struct ath_hw *ah = spec_priv->ah;
501 	struct ath_common *common = ath9k_hw_common(spec_priv->ah);
502 	u8 num_bins, *vdata = (u8 *)hdr;
503 	struct ath_radar_info *radar_info;
504 	int len = rs->rs_datalen;
505 	int i;
506 	int got_slen = 0;
507 	u8  *sample_start;
508 	int sample_bytes = 0;
509 	int ret = 0;
510 	u16 fft_len, sample_len, freq = ah->curchan->chan->center_freq;
511 	enum nl80211_channel_type chan_type;
512 	ath_cmn_fft_idx_validator *fft_idx_validator;
513 	ath_cmn_fft_sample_handler *fft_handler;
514 
515 	/* AR9280 and before report via ATH9K_PHYERR_RADAR, AR93xx and newer
516 	 * via ATH9K_PHYERR_SPECTRAL. Haven't seen ATH9K_PHYERR_FALSE_RADAR_EXT
517 	 * yet, but this is supposed to be possible as well.
518 	 */
519 	if (rs->rs_phyerr != ATH9K_PHYERR_RADAR &&
520 	    rs->rs_phyerr != ATH9K_PHYERR_FALSE_RADAR_EXT &&
521 	    rs->rs_phyerr != ATH9K_PHYERR_SPECTRAL)
522 		return 0;
523 
524 	/* check if spectral scan bit is set. This does not have to be checked
525 	 * if received through a SPECTRAL phy error, but shouldn't hurt.
526 	 */
527 	radar_info = ((struct ath_radar_info *)&vdata[len]) - 1;
528 	if (!(radar_info->pulse_bw_info & SPECTRAL_SCAN_BITMASK))
529 		return 0;
530 
531 	/* Output buffers are full, no need to process anything
532 	 * since there is no space to put the result anyway
533 	 */
534 	ret = ath_cmn_is_fft_buf_full(spec_priv);
535 	if (ret == 1) {
536 		ath_dbg(common, SPECTRAL_SCAN, "FFT report ignored, no space "
537 						"left on output buffers\n");
538 		return 1;
539 	}
540 
541 	chan_type = cfg80211_get_chandef_type(&common->hw->conf.chandef);
542 	if ((chan_type == NL80211_CHAN_HT40MINUS) ||
543 	    (chan_type == NL80211_CHAN_HT40PLUS)) {
544 		fft_len = SPECTRAL_HT20_40_TOTAL_DATA_LEN;
545 		sample_len = SPECTRAL_HT20_40_SAMPLE_LEN;
546 		num_bins = SPECTRAL_HT20_40_NUM_BINS;
547 		fft_idx_validator = &ath_cmn_max_idx_verify_ht20_40_fft;
548 		fft_handler = &ath_cmn_process_ht20_40_fft;
549 	} else {
550 		fft_len = SPECTRAL_HT20_TOTAL_DATA_LEN;
551 		sample_len = SPECTRAL_HT20_SAMPLE_LEN;
552 		num_bins = SPECTRAL_HT20_NUM_BINS;
553 		fft_idx_validator = ath_cmn_max_idx_verify_ht20_fft;
554 		fft_handler = &ath_cmn_process_ht20_fft;
555 	}
556 
557 	ath_dbg(common, SPECTRAL_SCAN, "Got radar dump bw_info: 0x%X,"
558 					"len: %i fft_len: %i\n",
559 					radar_info->pulse_bw_info,
560 					len,
561 					fft_len);
562 	sample_start = vdata;
563 	for (i = 0; i < len - 2; i++) {
564 		sample_bytes++;
565 
566 		/* Only a single sample received, no need to look
567 		 * for the sample's end, do the correction based
568 		 * on the packet's length instead. Note that hw
569 		 * will always put the radar_info structure on
570 		 * the end.
571 		 */
572 		if (len <= fft_len + 2) {
573 			sample_bytes = len - sizeof(struct ath_radar_info);
574 			got_slen = 1;
575 		}
576 
577 		/* Search for the end of the FFT frame between
578 		 * sample_len - 1 and sample_len + 2. exp_max is 3
579 		 * bits long and it's the only value on the last
580 		 * byte of the frame so since it'll be smaller than
581 		 * the next byte (the first bin of the next sample)
582 		 * 90% of the time, we can use it as a separator.
583 		 */
584 		if (vdata[i] <= 0x7 && sample_bytes >= sample_len - 1) {
585 
586 			/* Got a frame length within boundaries, there are
587 			 * four scenarios here:
588 			 *
589 			 * a) sample_len -> We got the correct length
590 			 * b) sample_len + 2 -> 2 bytes added around bin[31]
591 			 * c) sample_len - 1 -> The first byte is missing
592 			 * d) sample_len + 1 -> b + c at the same time
593 			 *
594 			 * When MAC adds 2 extra bytes, bin[31] and bin[32]
595 			 * have the same value, so we can use that for further
596 			 * verification in cases b and d.
597 			 */
598 
599 			/* Did we go too far ? If so we couldn't determine
600 			 * this sample's boundaries, discard any further
601 			 * data
602 			 */
603 			if ((sample_bytes > sample_len + 2) ||
604 			   ((sample_bytes > sample_len) &&
605 			   (sample_start[31] != sample_start[32])))
606 				break;
607 
608 			/* See if we got a valid frame by checking the
609 			 * consistency of mag_info fields. This is to
610 			 * prevent from "fixing" a correct frame.
611 			 * Failure is non-fatal, later frames may
612 			 * be valid.
613 			 */
614 			if (!fft_idx_validator(&vdata[i], i)) {
615 				ath_dbg(common, SPECTRAL_SCAN,
616 					"Found valid fft frame at %i\n", i);
617 				got_slen = 1;
618 			}
619 
620 			/* We expect 1 - 2 more bytes */
621 			else if ((sample_start[31] == sample_start[32]) &&
622 				(sample_bytes >= sample_len) &&
623 				(sample_bytes < sample_len + 2) &&
624 				(vdata[i + 1] <= 0x7))
625 				continue;
626 
627 			/* Try to distinguish cases a and c */
628 			else if ((sample_bytes == sample_len - 1) &&
629 				(vdata[i + 1] <= 0x7))
630 				continue;
631 
632 			got_slen = 1;
633 		}
634 
635 		if (got_slen) {
636 			ath_dbg(common, SPECTRAL_SCAN, "FFT frame len: %i\n",
637 				sample_bytes);
638 
639 			/* Only try to fix a frame if it's the only one
640 			 * on the report, else just skip it.
641 			 */
642 			if (sample_bytes != sample_len && len <= fft_len + 2) {
643 				ath_cmn_copy_fft_frame(sample_start,
644 						       sample_buf, sample_len,
645 						       sample_bytes);
646 
647 				fft_handler(rs, spec_priv, sample_buf,
648 					    tsf, freq, chan_type);
649 
650 				memset(sample_buf, 0, SPECTRAL_SAMPLE_MAX_LEN);
651 
652 				/* Mix the received bins to the /dev/random
653 				 * pool
654 				 */
655 				add_device_randomness(sample_buf, num_bins);
656 			}
657 
658 			/* Process a normal frame */
659 			if (sample_bytes == sample_len) {
660 				ret = fft_handler(rs, spec_priv, sample_start,
661 						  tsf, freq, chan_type);
662 
663 				/* Mix the received bins to the /dev/random
664 				 * pool
665 				 */
666 				add_device_randomness(sample_start, num_bins);
667 			}
668 
669 			/* Short report processed, break out of the
670 			 * loop.
671 			 */
672 			if (len <= fft_len + 2)
673 				break;
674 
675 			sample_start = &vdata[i + 1];
676 
677 			/* -1 to grab sample_len -1, -2 since
678 			 * they 'll get increased by one. In case
679 			 * of failure try to recover by going byte
680 			 * by byte instead.
681 			 */
682 			if (ret == 0) {
683 				i += num_bins - 2;
684 				sample_bytes = num_bins - 2;
685 			}
686 			got_slen = 0;
687 		}
688 	}
689 
690 	i -= num_bins - 2;
691 	if (len - i != sizeof(struct ath_radar_info))
692 		ath_dbg(common, SPECTRAL_SCAN, "FFT report truncated"
693 						"(bytes left: %i)\n",
694 						len - i);
695 	return 1;
696 }
697 EXPORT_SYMBOL(ath_cmn_process_fft);
698 
699 /*********************/
700 /* spectral_scan_ctl */
701 /*********************/
702 
703 static ssize_t read_file_spec_scan_ctl(struct file *file, char __user *user_buf,
704 				       size_t count, loff_t *ppos)
705 {
706 	struct ath_spec_scan_priv *spec_priv = file->private_data;
707 	char *mode = "";
708 	unsigned int len;
709 
710 	switch (spec_priv->spectral_mode) {
711 	case SPECTRAL_DISABLED:
712 		mode = "disable";
713 		break;
714 	case SPECTRAL_BACKGROUND:
715 		mode = "background";
716 		break;
717 	case SPECTRAL_CHANSCAN:
718 		mode = "chanscan";
719 		break;
720 	case SPECTRAL_MANUAL:
721 		mode = "manual";
722 		break;
723 	}
724 	len = strlen(mode);
725 	return simple_read_from_buffer(user_buf, count, ppos, mode, len);
726 }
727 
728 void ath9k_cmn_spectral_scan_trigger(struct ath_common *common,
729 				 struct ath_spec_scan_priv *spec_priv)
730 {
731 	struct ath_hw *ah = spec_priv->ah;
732 	u32 rxfilter;
733 
734 	if (config_enabled(CONFIG_ATH9K_TX99))
735 		return;
736 
737 	if (!ath9k_hw_ops(ah)->spectral_scan_trigger) {
738 		ath_err(common, "spectrum analyzer not implemented on this hardware\n");
739 		return;
740 	}
741 
742 	ath_ps_ops(common)->wakeup(common);
743 	rxfilter = ath9k_hw_getrxfilter(ah);
744 	ath9k_hw_setrxfilter(ah, rxfilter |
745 				 ATH9K_RX_FILTER_PHYRADAR |
746 				 ATH9K_RX_FILTER_PHYERR);
747 
748 	/* TODO: usually this should not be neccesary, but for some reason
749 	 * (or in some mode?) the trigger must be called after the
750 	 * configuration, otherwise the register will have its values reset
751 	 * (on my ar9220 to value 0x01002310)
752 	 */
753 	ath9k_cmn_spectral_scan_config(common, spec_priv, spec_priv->spectral_mode);
754 	ath9k_hw_ops(ah)->spectral_scan_trigger(ah);
755 	ath_ps_ops(common)->restore(common);
756 }
757 EXPORT_SYMBOL(ath9k_cmn_spectral_scan_trigger);
758 
759 int ath9k_cmn_spectral_scan_config(struct ath_common *common,
760 			       struct ath_spec_scan_priv *spec_priv,
761 			       enum spectral_mode spectral_mode)
762 {
763 	struct ath_hw *ah = spec_priv->ah;
764 
765 	if (!ath9k_hw_ops(ah)->spectral_scan_trigger) {
766 		ath_err(common, "spectrum analyzer not implemented on this hardware\n");
767 		return -1;
768 	}
769 
770 	switch (spectral_mode) {
771 	case SPECTRAL_DISABLED:
772 		spec_priv->spec_config.enabled = 0;
773 		break;
774 	case SPECTRAL_BACKGROUND:
775 		/* send endless samples.
776 		 * TODO: is this really useful for "background"?
777 		 */
778 		spec_priv->spec_config.endless = 1;
779 		spec_priv->spec_config.enabled = 1;
780 		break;
781 	case SPECTRAL_CHANSCAN:
782 	case SPECTRAL_MANUAL:
783 		spec_priv->spec_config.endless = 0;
784 		spec_priv->spec_config.enabled = 1;
785 		break;
786 	default:
787 		return -1;
788 	}
789 
790 	ath_ps_ops(common)->wakeup(common);
791 	ath9k_hw_ops(ah)->spectral_scan_config(ah, &spec_priv->spec_config);
792 	ath_ps_ops(common)->restore(common);
793 
794 	spec_priv->spectral_mode = spectral_mode;
795 
796 	return 0;
797 }
798 EXPORT_SYMBOL(ath9k_cmn_spectral_scan_config);
799 
800 static ssize_t write_file_spec_scan_ctl(struct file *file,
801 					const char __user *user_buf,
802 					size_t count, loff_t *ppos)
803 {
804 	struct ath_spec_scan_priv *spec_priv = file->private_data;
805 	struct ath_common *common = ath9k_hw_common(spec_priv->ah);
806 	char buf[32];
807 	ssize_t len;
808 
809 	if (config_enabled(CONFIG_ATH9K_TX99))
810 		return -EOPNOTSUPP;
811 
812 	len = min(count, sizeof(buf) - 1);
813 	if (copy_from_user(buf, user_buf, len))
814 		return -EFAULT;
815 
816 	buf[len] = '\0';
817 
818 	if (strncmp("trigger", buf, 7) == 0) {
819 		ath9k_cmn_spectral_scan_trigger(common, spec_priv);
820 	} else if (strncmp("background", buf, 10) == 0) {
821 		ath9k_cmn_spectral_scan_config(common, spec_priv, SPECTRAL_BACKGROUND);
822 		ath_dbg(common, CONFIG, "spectral scan: background mode enabled\n");
823 	} else if (strncmp("chanscan", buf, 8) == 0) {
824 		ath9k_cmn_spectral_scan_config(common, spec_priv, SPECTRAL_CHANSCAN);
825 		ath_dbg(common, CONFIG, "spectral scan: channel scan mode enabled\n");
826 	} else if (strncmp("manual", buf, 6) == 0) {
827 		ath9k_cmn_spectral_scan_config(common, spec_priv, SPECTRAL_MANUAL);
828 		ath_dbg(common, CONFIG, "spectral scan: manual mode enabled\n");
829 	} else if (strncmp("disable", buf, 7) == 0) {
830 		ath9k_cmn_spectral_scan_config(common, spec_priv, SPECTRAL_DISABLED);
831 		ath_dbg(common, CONFIG, "spectral scan: disabled\n");
832 	} else {
833 		return -EINVAL;
834 	}
835 
836 	return count;
837 }
838 
839 static const struct file_operations fops_spec_scan_ctl = {
840 	.read = read_file_spec_scan_ctl,
841 	.write = write_file_spec_scan_ctl,
842 	.open = simple_open,
843 	.owner = THIS_MODULE,
844 	.llseek = default_llseek,
845 };
846 
847 /*************************/
848 /* spectral_short_repeat */
849 /*************************/
850 
851 static ssize_t read_file_spectral_short_repeat(struct file *file,
852 					       char __user *user_buf,
853 					       size_t count, loff_t *ppos)
854 {
855 	struct ath_spec_scan_priv *spec_priv = file->private_data;
856 	char buf[32];
857 	unsigned int len;
858 
859 	len = sprintf(buf, "%d\n", spec_priv->spec_config.short_repeat);
860 	return simple_read_from_buffer(user_buf, count, ppos, buf, len);
861 }
862 
863 static ssize_t write_file_spectral_short_repeat(struct file *file,
864 						const char __user *user_buf,
865 						size_t count, loff_t *ppos)
866 {
867 	struct ath_spec_scan_priv *spec_priv = file->private_data;
868 	unsigned long val;
869 	char buf[32];
870 	ssize_t len;
871 
872 	len = min(count, sizeof(buf) - 1);
873 	if (copy_from_user(buf, user_buf, len))
874 		return -EFAULT;
875 
876 	buf[len] = '\0';
877 	if (kstrtoul(buf, 0, &val))
878 		return -EINVAL;
879 
880 	if (val > 1)
881 		return -EINVAL;
882 
883 	spec_priv->spec_config.short_repeat = val;
884 	return count;
885 }
886 
887 static const struct file_operations fops_spectral_short_repeat = {
888 	.read = read_file_spectral_short_repeat,
889 	.write = write_file_spectral_short_repeat,
890 	.open = simple_open,
891 	.owner = THIS_MODULE,
892 	.llseek = default_llseek,
893 };
894 
895 /******************/
896 /* spectral_count */
897 /******************/
898 
899 static ssize_t read_file_spectral_count(struct file *file,
900 					char __user *user_buf,
901 					size_t count, loff_t *ppos)
902 {
903 	struct ath_spec_scan_priv *spec_priv = file->private_data;
904 	char buf[32];
905 	unsigned int len;
906 
907 	len = sprintf(buf, "%d\n", spec_priv->spec_config.count);
908 	return simple_read_from_buffer(user_buf, count, ppos, buf, len);
909 }
910 
911 static ssize_t write_file_spectral_count(struct file *file,
912 					 const char __user *user_buf,
913 					 size_t count, loff_t *ppos)
914 {
915 	struct ath_spec_scan_priv *spec_priv = file->private_data;
916 	unsigned long val;
917 	char buf[32];
918 	ssize_t len;
919 
920 	len = min(count, sizeof(buf) - 1);
921 	if (copy_from_user(buf, user_buf, len))
922 		return -EFAULT;
923 
924 	buf[len] = '\0';
925 	if (kstrtoul(buf, 0, &val))
926 		return -EINVAL;
927 
928 	if (val > 255)
929 		return -EINVAL;
930 
931 	spec_priv->spec_config.count = val;
932 	return count;
933 }
934 
935 static const struct file_operations fops_spectral_count = {
936 	.read = read_file_spectral_count,
937 	.write = write_file_spectral_count,
938 	.open = simple_open,
939 	.owner = THIS_MODULE,
940 	.llseek = default_llseek,
941 };
942 
943 /*******************/
944 /* spectral_period */
945 /*******************/
946 
947 static ssize_t read_file_spectral_period(struct file *file,
948 					 char __user *user_buf,
949 					 size_t count, loff_t *ppos)
950 {
951 	struct ath_spec_scan_priv *spec_priv = file->private_data;
952 	char buf[32];
953 	unsigned int len;
954 
955 	len = sprintf(buf, "%d\n", spec_priv->spec_config.period);
956 	return simple_read_from_buffer(user_buf, count, ppos, buf, len);
957 }
958 
959 static ssize_t write_file_spectral_period(struct file *file,
960 					  const char __user *user_buf,
961 					  size_t count, loff_t *ppos)
962 {
963 	struct ath_spec_scan_priv *spec_priv = file->private_data;
964 	unsigned long val;
965 	char buf[32];
966 	ssize_t len;
967 
968 	len = min(count, sizeof(buf) - 1);
969 	if (copy_from_user(buf, user_buf, len))
970 		return -EFAULT;
971 
972 	buf[len] = '\0';
973 	if (kstrtoul(buf, 0, &val))
974 		return -EINVAL;
975 
976 	if (val > 255)
977 		return -EINVAL;
978 
979 	spec_priv->spec_config.period = val;
980 	return count;
981 }
982 
983 static const struct file_operations fops_spectral_period = {
984 	.read = read_file_spectral_period,
985 	.write = write_file_spectral_period,
986 	.open = simple_open,
987 	.owner = THIS_MODULE,
988 	.llseek = default_llseek,
989 };
990 
991 /***********************/
992 /* spectral_fft_period */
993 /***********************/
994 
995 static ssize_t read_file_spectral_fft_period(struct file *file,
996 					     char __user *user_buf,
997 					     size_t count, loff_t *ppos)
998 {
999 	struct ath_spec_scan_priv *spec_priv = file->private_data;
1000 	char buf[32];
1001 	unsigned int len;
1002 
1003 	len = sprintf(buf, "%d\n", spec_priv->spec_config.fft_period);
1004 	return simple_read_from_buffer(user_buf, count, ppos, buf, len);
1005 }
1006 
1007 static ssize_t write_file_spectral_fft_period(struct file *file,
1008 					      const char __user *user_buf,
1009 					      size_t count, loff_t *ppos)
1010 {
1011 	struct ath_spec_scan_priv *spec_priv = file->private_data;
1012 	unsigned long val;
1013 	char buf[32];
1014 	ssize_t len;
1015 
1016 	len = min(count, sizeof(buf) - 1);
1017 	if (copy_from_user(buf, user_buf, len))
1018 		return -EFAULT;
1019 
1020 	buf[len] = '\0';
1021 	if (kstrtoul(buf, 0, &val))
1022 		return -EINVAL;
1023 
1024 	if (val > 15)
1025 		return -EINVAL;
1026 
1027 	spec_priv->spec_config.fft_period = val;
1028 	return count;
1029 }
1030 
1031 static const struct file_operations fops_spectral_fft_period = {
1032 	.read = read_file_spectral_fft_period,
1033 	.write = write_file_spectral_fft_period,
1034 	.open = simple_open,
1035 	.owner = THIS_MODULE,
1036 	.llseek = default_llseek,
1037 };
1038 
1039 /*******************/
1040 /* Relay interface */
1041 /*******************/
1042 
1043 static struct dentry *create_buf_file_handler(const char *filename,
1044 					      struct dentry *parent,
1045 					      umode_t mode,
1046 					      struct rchan_buf *buf,
1047 					      int *is_global)
1048 {
1049 	struct dentry *buf_file;
1050 
1051 	buf_file = debugfs_create_file(filename, mode, parent, buf,
1052 				       &relay_file_operations);
1053 	*is_global = 1;
1054 	return buf_file;
1055 }
1056 
1057 static int remove_buf_file_handler(struct dentry *dentry)
1058 {
1059 	debugfs_remove(dentry);
1060 
1061 	return 0;
1062 }
1063 
1064 static struct rchan_callbacks rfs_spec_scan_cb = {
1065 	.create_buf_file = create_buf_file_handler,
1066 	.remove_buf_file = remove_buf_file_handler,
1067 };
1068 
1069 /*********************/
1070 /* Debug Init/Deinit */
1071 /*********************/
1072 
1073 void ath9k_cmn_spectral_deinit_debug(struct ath_spec_scan_priv *spec_priv)
1074 {
1075 	if (config_enabled(CONFIG_ATH9K_DEBUGFS)) {
1076 		relay_close(spec_priv->rfs_chan_spec_scan);
1077 		spec_priv->rfs_chan_spec_scan = NULL;
1078 	}
1079 }
1080 EXPORT_SYMBOL(ath9k_cmn_spectral_deinit_debug);
1081 
1082 void ath9k_cmn_spectral_init_debug(struct ath_spec_scan_priv *spec_priv,
1083 				   struct dentry *debugfs_phy)
1084 {
1085 	spec_priv->rfs_chan_spec_scan = relay_open("spectral_scan",
1086 					    debugfs_phy,
1087 					    1024, 256, &rfs_spec_scan_cb,
1088 					    NULL);
1089 	debugfs_create_file("spectral_scan_ctl",
1090 			    S_IRUSR | S_IWUSR,
1091 			    debugfs_phy, spec_priv,
1092 			    &fops_spec_scan_ctl);
1093 	debugfs_create_file("spectral_short_repeat",
1094 			    S_IRUSR | S_IWUSR,
1095 			    debugfs_phy, spec_priv,
1096 			    &fops_spectral_short_repeat);
1097 	debugfs_create_file("spectral_count",
1098 			    S_IRUSR | S_IWUSR,
1099 			    debugfs_phy, spec_priv,
1100 			    &fops_spectral_count);
1101 	debugfs_create_file("spectral_period",
1102 			    S_IRUSR | S_IWUSR,
1103 			    debugfs_phy, spec_priv,
1104 			    &fops_spectral_period);
1105 	debugfs_create_file("spectral_fft_period",
1106 			    S_IRUSR | S_IWUSR,
1107 			    debugfs_phy, spec_priv,
1108 			    &fops_spectral_fft_period);
1109 }
1110 EXPORT_SYMBOL(ath9k_cmn_spectral_init_debug);
1111