xref: /linux/drivers/net/wireless/ath/ath9k/common-spectral.c (revision c532de5a67a70f8533d495f8f2aaa9a0491c3ad0)
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_ht20(mag_info->all_bins);
63 	max_magnitude = spectral_max_magnitude(mag_info->all_bins);
64 
65 	max_exp = mag_info->max_exp & 0xf;
66 
67 	/* Don't try to read something outside the read buffer
68 	 * in case of a missing byte (so bins[0] will be outside
69 	 * the read buffer)
70 	 */
71 	if (bytes_read < SPECTRAL_HT20_SAMPLE_LEN && max_index < 1)
72 		return -1;
73 
74 	if ((sample[max_index] & 0xf8) != ((max_magnitude >> max_exp) & 0xf8))
75 		return -1;
76 	else
77 		return 0;
78 }
79 
80 static int
81 ath_cmn_max_idx_verify_ht20_40_fft(u8 *sample_end, int bytes_read)
82 {
83 	struct ath_ht20_40_mag_info *mag_info;
84 	u8 *sample;
85 	u16 lower_mag, upper_mag;
86 	u8 lower_max_index, upper_max_index;
87 	u8 max_exp;
88 	int dc_pos = SPECTRAL_HT20_40_NUM_BINS / 2;
89 
90 	/* Sanity check so that we don't read outside the read
91 	 * buffer
92 	 */
93 	if (bytes_read < SPECTRAL_HT20_40_SAMPLE_LEN - 1)
94 		return -1;
95 
96 	mag_info = (struct ath_ht20_40_mag_info *) (sample_end -
97 				sizeof(struct ath_ht20_40_mag_info) + 1);
98 
99 	sample = sample_end - SPECTRAL_HT20_40_SAMPLE_LEN + 1;
100 
101 	lower_mag = spectral_max_magnitude(mag_info->lower_bins);
102 	lower_max_index = spectral_max_index_ht40(mag_info->lower_bins);
103 
104 	upper_mag = spectral_max_magnitude(mag_info->upper_bins);
105 	upper_max_index = spectral_max_index_ht40(mag_info->upper_bins);
106 
107 	max_exp = mag_info->max_exp & 0xf;
108 
109 	/* Don't try to read something outside the read buffer
110 	 * in case of a missing byte (so bins[0] will be outside
111 	 * the read buffer)
112 	 */
113 	if (bytes_read < SPECTRAL_HT20_40_SAMPLE_LEN &&
114 	   ((upper_max_index < 1) || (lower_max_index < 1)))
115 		return -1;
116 
117 	if (((sample[upper_max_index + dc_pos] & 0xf8) !=
118 	     ((upper_mag >> max_exp) & 0xf8)) ||
119 	    ((sample[lower_max_index] & 0xf8) !=
120 	     ((lower_mag >> max_exp) & 0xf8)))
121 		return -1;
122 	else
123 		return 0;
124 }
125 
126 typedef int (ath_cmn_fft_sample_handler) (struct ath_rx_status *rs,
127 			struct ath_spec_scan_priv *spec_priv,
128 			u8 *sample_buf, u64 tsf, u16 freq, int chan_type);
129 
130 static int
131 ath_cmn_process_ht20_fft(struct ath_rx_status *rs,
132 			struct ath_spec_scan_priv *spec_priv,
133 			u8 *sample_buf,
134 			u64 tsf, u16 freq, int chan_type)
135 {
136 	struct fft_sample_ht20 fft_sample_20;
137 	struct ath_common *common = ath9k_hw_common(spec_priv->ah);
138 	struct ath_hw *ah = spec_priv->ah;
139 	struct ath_ht20_mag_info *mag_info;
140 	struct fft_sample_tlv *tlv;
141 	int i = 0;
142 	int ret = 0;
143 	int dc_pos = SPECTRAL_HT20_NUM_BINS / 2;
144 	u16 magnitude, tmp_mag, length;
145 	u8 max_index, bitmap_w, max_exp;
146 
147 	length = sizeof(fft_sample_20) - sizeof(struct fft_sample_tlv);
148 	fft_sample_20.tlv.type = ATH_FFT_SAMPLE_HT20;
149 	fft_sample_20.tlv.length = __cpu_to_be16(length);
150 	fft_sample_20.freq = __cpu_to_be16(freq);
151 	fft_sample_20.rssi = fix_rssi_inv_only(rs->rs_rssi_ctl[0]);
152 	fft_sample_20.noise = ah->noise;
153 
154 	mag_info = (struct ath_ht20_mag_info *) (sample_buf +
155 					SPECTRAL_HT20_NUM_BINS);
156 
157 	magnitude = spectral_max_magnitude(mag_info->all_bins);
158 	fft_sample_20.max_magnitude = __cpu_to_be16(magnitude);
159 
160 	max_index = spectral_max_index_ht20(mag_info->all_bins);
161 	fft_sample_20.max_index = max_index;
162 
163 	bitmap_w = spectral_bitmap_weight(mag_info->all_bins);
164 	fft_sample_20.bitmap_weight = bitmap_w;
165 
166 	max_exp = mag_info->max_exp & 0xf;
167 	fft_sample_20.max_exp = max_exp;
168 
169 	fft_sample_20.tsf = __cpu_to_be64(tsf);
170 
171 	memcpy(fft_sample_20.data, sample_buf, SPECTRAL_HT20_NUM_BINS);
172 
173 	ath_dbg(common, SPECTRAL_SCAN, "FFT HT20 frame: max mag 0x%X,"
174 					"max_mag_idx %i\n",
175 					magnitude >> max_exp,
176 					max_index);
177 
178 	if ((fft_sample_20.data[max_index] & 0xf8) !=
179 	    ((magnitude >> max_exp) & 0xf8)) {
180 		ath_dbg(common, SPECTRAL_SCAN, "Magnitude mismatch !\n");
181 		ret = -1;
182 	}
183 
184 	/* DC value (value in the middle) is the blind spot of the spectral
185 	 * sample and invalid, interpolate it.
186 	 */
187 	fft_sample_20.data[dc_pos] = (fft_sample_20.data[dc_pos + 1] +
188 					fft_sample_20.data[dc_pos - 1]) / 2;
189 
190 	/* Check if the maximum magnitude is indeed maximum,
191 	 * also if the maximum value was at dc_pos, calculate
192 	 * a new one (since value at dc_pos is invalid).
193 	 */
194 	if (max_index == dc_pos) {
195 		tmp_mag = 0;
196 		for (i = 0; i < dc_pos; i++) {
197 			if (fft_sample_20.data[i] > tmp_mag) {
198 				tmp_mag = fft_sample_20.data[i];
199 				fft_sample_20.max_index = i;
200 			}
201 		}
202 
203 		magnitude = tmp_mag << max_exp;
204 		fft_sample_20.max_magnitude = __cpu_to_be16(magnitude);
205 
206 		ath_dbg(common, SPECTRAL_SCAN,
207 			"Calculated new lower max 0x%X at %i\n",
208 			tmp_mag, fft_sample_20.max_index);
209 	} else
210 	for (i = 0; i < SPECTRAL_HT20_NUM_BINS; i++) {
211 		if (fft_sample_20.data[i] == (magnitude >> max_exp))
212 			ath_dbg(common, SPECTRAL_SCAN,
213 				"Got max: 0x%X at index %i\n",
214 				fft_sample_20.data[i], i);
215 
216 		if (fft_sample_20.data[i] > (magnitude >> max_exp)) {
217 			ath_dbg(common, SPECTRAL_SCAN,
218 				"Got bin %i greater than max: 0x%X\n",
219 				i, fft_sample_20.data[i]);
220 			ret = -1;
221 		}
222 	}
223 
224 	if (ret < 0)
225 		return ret;
226 
227 	tlv = (struct fft_sample_tlv *)&fft_sample_20;
228 
229 	ath_debug_send_fft_sample(spec_priv, tlv);
230 
231 	return 0;
232 }
233 
234 static int
235 ath_cmn_process_ht20_40_fft(struct ath_rx_status *rs,
236 			struct ath_spec_scan_priv *spec_priv,
237 			u8 *sample_buf,
238 			u64 tsf, u16 freq, int chan_type)
239 {
240 	struct fft_sample_ht20_40 fft_sample_40;
241 	struct ath_common *common = ath9k_hw_common(spec_priv->ah);
242 	struct ath_hw *ah = spec_priv->ah;
243 	struct ath9k_hw_cal_data *caldata = ah->caldata;
244 	struct ath_ht20_40_mag_info *mag_info;
245 	struct fft_sample_tlv *tlv;
246 	int dc_pos = SPECTRAL_HT20_40_NUM_BINS / 2;
247 	int i = 0;
248 	int ret = 0;
249 	s16 ext_nf;
250 	u16 lower_mag, upper_mag, tmp_mag, length;
251 	s8 lower_rssi, upper_rssi;
252 	u8 lower_max_index, upper_max_index;
253 	u8 lower_bitmap_w, upper_bitmap_w, max_exp;
254 
255 	if (caldata)
256 		ext_nf = ath9k_hw_getchan_noise(ah, ah->curchan,
257 				caldata->nfCalHist[3].privNF);
258 	else
259 		ext_nf = ATH_DEFAULT_NOISE_FLOOR;
260 
261 	length = sizeof(fft_sample_40) - sizeof(struct fft_sample_tlv);
262 	fft_sample_40.tlv.type = ATH_FFT_SAMPLE_HT20_40;
263 	fft_sample_40.tlv.length = __cpu_to_be16(length);
264 	fft_sample_40.freq = __cpu_to_be16(freq);
265 	fft_sample_40.channel_type = chan_type;
266 
267 	if (chan_type == NL80211_CHAN_HT40PLUS) {
268 		lower_rssi = fix_rssi_inv_only(rs->rs_rssi_ctl[0]);
269 		upper_rssi = fix_rssi_inv_only(rs->rs_rssi_ext[0]);
270 
271 		fft_sample_40.lower_noise = ah->noise;
272 		fft_sample_40.upper_noise = ext_nf;
273 	} else {
274 		lower_rssi = fix_rssi_inv_only(rs->rs_rssi_ext[0]);
275 		upper_rssi = fix_rssi_inv_only(rs->rs_rssi_ctl[0]);
276 
277 		fft_sample_40.lower_noise = ext_nf;
278 		fft_sample_40.upper_noise = ah->noise;
279 	}
280 
281 	fft_sample_40.lower_rssi = lower_rssi;
282 	fft_sample_40.upper_rssi = upper_rssi;
283 
284 	mag_info = (struct ath_ht20_40_mag_info *) (sample_buf +
285 					SPECTRAL_HT20_40_NUM_BINS);
286 
287 	lower_mag = spectral_max_magnitude(mag_info->lower_bins);
288 	fft_sample_40.lower_max_magnitude = __cpu_to_be16(lower_mag);
289 
290 	upper_mag = spectral_max_magnitude(mag_info->upper_bins);
291 	fft_sample_40.upper_max_magnitude = __cpu_to_be16(upper_mag);
292 
293 	lower_max_index = spectral_max_index_ht40(mag_info->lower_bins);
294 	fft_sample_40.lower_max_index = lower_max_index;
295 
296 	upper_max_index = spectral_max_index_ht40(mag_info->upper_bins);
297 	fft_sample_40.upper_max_index = upper_max_index;
298 
299 	lower_bitmap_w = spectral_bitmap_weight(mag_info->lower_bins);
300 	fft_sample_40.lower_bitmap_weight = lower_bitmap_w;
301 
302 	upper_bitmap_w = spectral_bitmap_weight(mag_info->upper_bins);
303 	fft_sample_40.upper_bitmap_weight = upper_bitmap_w;
304 
305 	max_exp = mag_info->max_exp & 0xf;
306 	fft_sample_40.max_exp = max_exp;
307 
308 	fft_sample_40.tsf = __cpu_to_be64(tsf);
309 
310 	memcpy(fft_sample_40.data, sample_buf, SPECTRAL_HT20_40_NUM_BINS);
311 
312 	ath_dbg(common, SPECTRAL_SCAN, "FFT HT20/40 frame: lower mag 0x%X,"
313 					"lower_mag_idx %i, upper mag 0x%X,"
314 					"upper_mag_idx %i\n",
315 					lower_mag >> max_exp,
316 					lower_max_index,
317 					upper_mag >> max_exp,
318 					upper_max_index);
319 
320 	/* Check if we got the expected magnitude values at
321 	 * the expected bins
322 	 */
323 	if (((fft_sample_40.data[upper_max_index + dc_pos] & 0xf8)
324 	    != ((upper_mag >> max_exp) & 0xf8)) ||
325 	   ((fft_sample_40.data[lower_max_index] & 0xf8)
326 	    != ((lower_mag >> max_exp) & 0xf8))) {
327 		ath_dbg(common, SPECTRAL_SCAN, "Magnitude mismatch !\n");
328 		ret = -1;
329 	}
330 
331 	/* DC value (value in the middle) is the blind spot of the spectral
332 	 * sample and invalid, interpolate it.
333 	 */
334 	fft_sample_40.data[dc_pos] = (fft_sample_40.data[dc_pos + 1] +
335 					fft_sample_40.data[dc_pos - 1]) / 2;
336 
337 	/* Check if the maximum magnitudes are indeed maximum,
338 	 * also if the maximum value was at dc_pos, calculate
339 	 * a new one (since value at dc_pos is invalid).
340 	 */
341 	if (lower_max_index == dc_pos) {
342 		tmp_mag = 0;
343 		for (i = 0; i < dc_pos; i++) {
344 			if (fft_sample_40.data[i] > tmp_mag) {
345 				tmp_mag = fft_sample_40.data[i];
346 				fft_sample_40.lower_max_index = i;
347 			}
348 		}
349 
350 		lower_mag = tmp_mag << max_exp;
351 		fft_sample_40.lower_max_magnitude = __cpu_to_be16(lower_mag);
352 
353 		ath_dbg(common, SPECTRAL_SCAN,
354 			"Calculated new lower max 0x%X at %i\n",
355 			tmp_mag, fft_sample_40.lower_max_index);
356 	} else
357 	for (i = 0; i < dc_pos; i++) {
358 		if (fft_sample_40.data[i] == (lower_mag >> max_exp))
359 			ath_dbg(common, SPECTRAL_SCAN,
360 				"Got lower mag: 0x%X at index %i\n",
361 				fft_sample_40.data[i], i);
362 
363 		if (fft_sample_40.data[i] > (lower_mag >> max_exp)) {
364 			ath_dbg(common, SPECTRAL_SCAN,
365 				"Got lower bin %i higher than max: 0x%X\n",
366 				i, fft_sample_40.data[i]);
367 			ret = -1;
368 		}
369 	}
370 
371 	if (upper_max_index == dc_pos) {
372 		tmp_mag = 0;
373 		for (i = dc_pos; i < SPECTRAL_HT20_40_NUM_BINS; i++) {
374 			if (fft_sample_40.data[i] > tmp_mag) {
375 				tmp_mag = fft_sample_40.data[i];
376 				fft_sample_40.upper_max_index = i;
377 			}
378 		}
379 		upper_mag = tmp_mag << max_exp;
380 		fft_sample_40.upper_max_magnitude = __cpu_to_be16(upper_mag);
381 
382 		ath_dbg(common, SPECTRAL_SCAN,
383 			"Calculated new upper max 0x%X at %i\n",
384 			tmp_mag, fft_sample_40.upper_max_index);
385 	} else
386 	for (i = dc_pos; i < SPECTRAL_HT20_40_NUM_BINS; i++) {
387 		if (fft_sample_40.data[i] == (upper_mag >> max_exp))
388 			ath_dbg(common, SPECTRAL_SCAN,
389 				"Got upper mag: 0x%X at index %i\n",
390 				fft_sample_40.data[i], i);
391 
392 		if (fft_sample_40.data[i] > (upper_mag >> max_exp)) {
393 			ath_dbg(common, SPECTRAL_SCAN,
394 				"Got upper bin %i higher than max: 0x%X\n",
395 				i, fft_sample_40.data[i]);
396 
397 			ret = -1;
398 		}
399 	}
400 
401 	if (ret < 0)
402 		return ret;
403 
404 	tlv = (struct fft_sample_tlv *)&fft_sample_40;
405 
406 	ath_debug_send_fft_sample(spec_priv, tlv);
407 
408 	return 0;
409 }
410 
411 static inline void
412 ath_cmn_copy_fft_frame(u8 *in, u8 *out, int sample_len, int sample_bytes)
413 {
414 	switch (sample_bytes - sample_len) {
415 	case -1:
416 		/* First byte missing */
417 		memcpy(&out[1], in,
418 		       sample_len - 1);
419 		break;
420 	case 0:
421 		/* Length correct, nothing to do. */
422 		memcpy(out, in, sample_len);
423 		break;
424 	case 1:
425 		/* MAC added 2 extra bytes AND first byte
426 		 * is missing.
427 		 */
428 		memcpy(&out[1], in, 30);
429 		out[31] = in[31];
430 		memcpy(&out[32], &in[33],
431 		       sample_len - 32);
432 		break;
433 	case 2:
434 		/* MAC added 2 extra bytes at bin 30 and 32,
435 		 * remove them.
436 		 */
437 		memcpy(out, in, 30);
438 		out[30] = in[31];
439 		memcpy(&out[31], &in[33],
440 		       sample_len - 31);
441 		break;
442 	default:
443 		break;
444 	}
445 }
446 
447 static int
448 ath_cmn_is_fft_buf_full(struct ath_spec_scan_priv *spec_priv)
449 {
450 	int i = 0;
451 	int ret = 0;
452 	struct rchan_buf *buf;
453 	struct rchan *rc = spec_priv->rfs_chan_spec_scan;
454 
455 	for_each_possible_cpu(i) {
456 		if ((buf = *per_cpu_ptr(rc->buf, i))) {
457 			ret += relay_buf_full(buf);
458 		}
459 	}
460 
461 	if (ret)
462 		return 1;
463 	else
464 		return 0;
465 }
466 
467 /* returns 1 if this was a spectral frame, even if not handled. */
468 int ath_cmn_process_fft(struct ath_spec_scan_priv *spec_priv, struct ieee80211_hdr *hdr,
469 		    struct ath_rx_status *rs, u64 tsf)
470 {
471 	u8 sample_buf[SPECTRAL_SAMPLE_MAX_LEN] = {0};
472 	struct ath_hw *ah = spec_priv->ah;
473 	struct ath_common *common = ath9k_hw_common(spec_priv->ah);
474 	struct ath_softc *sc = common->priv;
475 	u8 num_bins, *vdata = (u8 *)hdr;
476 	struct ath_radar_info *radar_info;
477 	int len = rs->rs_datalen;
478 	int i;
479 	int got_slen = 0;
480 	u8  *sample_start;
481 	int sample_bytes = 0;
482 	int ret = 0;
483 	u16 fft_len, sample_len, freq = ah->curchan->chan->center_freq;
484 	enum nl80211_channel_type chan_type;
485 	ath_cmn_fft_idx_validator *fft_idx_validator;
486 	ath_cmn_fft_sample_handler *fft_handler;
487 
488 	/* AR9280 and before report via ATH9K_PHYERR_RADAR, AR93xx and newer
489 	 * via ATH9K_PHYERR_SPECTRAL. Haven't seen ATH9K_PHYERR_FALSE_RADAR_EXT
490 	 * yet, but this is supposed to be possible as well.
491 	 */
492 	if (rs->rs_phyerr != ATH9K_PHYERR_RADAR &&
493 	    rs->rs_phyerr != ATH9K_PHYERR_FALSE_RADAR_EXT &&
494 	    rs->rs_phyerr != ATH9K_PHYERR_SPECTRAL)
495 		return 0;
496 
497 	/* check if spectral scan bit is set. This does not have to be checked
498 	 * if received through a SPECTRAL phy error, but shouldn't hurt.
499 	 */
500 	radar_info = ((struct ath_radar_info *)&vdata[len]) - 1;
501 	if (!(radar_info->pulse_bw_info & SPECTRAL_SCAN_BITMASK))
502 		return 0;
503 
504 	if (!spec_priv->rfs_chan_spec_scan)
505 		return 1;
506 
507 	/* Output buffers are full, no need to process anything
508 	 * since there is no space to put the result anyway
509 	 */
510 	ret = ath_cmn_is_fft_buf_full(spec_priv);
511 	if (ret == 1) {
512 		ath_dbg(common, SPECTRAL_SCAN, "FFT report ignored, no space "
513 						"left on output buffers\n");
514 		return 1;
515 	}
516 
517 	chan_type = cfg80211_get_chandef_type(&common->hw->conf.chandef);
518 	if ((chan_type == NL80211_CHAN_HT40MINUS) ||
519 	    (chan_type == NL80211_CHAN_HT40PLUS)) {
520 		fft_len = SPECTRAL_HT20_40_TOTAL_DATA_LEN;
521 		sample_len = SPECTRAL_HT20_40_SAMPLE_LEN;
522 		num_bins = SPECTRAL_HT20_40_NUM_BINS;
523 		fft_idx_validator = &ath_cmn_max_idx_verify_ht20_40_fft;
524 		fft_handler = &ath_cmn_process_ht20_40_fft;
525 	} else {
526 		fft_len = SPECTRAL_HT20_TOTAL_DATA_LEN;
527 		sample_len = SPECTRAL_HT20_SAMPLE_LEN;
528 		num_bins = SPECTRAL_HT20_NUM_BINS;
529 		fft_idx_validator = ath_cmn_max_idx_verify_ht20_fft;
530 		fft_handler = &ath_cmn_process_ht20_fft;
531 	}
532 
533 	ath_dbg(common, SPECTRAL_SCAN, "Got radar dump bw_info: 0x%X,"
534 					"len: %i fft_len: %i\n",
535 					radar_info->pulse_bw_info,
536 					len,
537 					fft_len);
538 	sample_start = vdata;
539 	for (i = 0; i < len - 2; i++) {
540 		sample_bytes++;
541 
542 		/* Only a single sample received, no need to look
543 		 * for the sample's end, do the correction based
544 		 * on the packet's length instead. Note that hw
545 		 * will always put the radar_info structure on
546 		 * the end.
547 		 */
548 		if (len <= fft_len + 2) {
549 			sample_bytes = len - sizeof(struct ath_radar_info);
550 			got_slen = 1;
551 		}
552 
553 		/* Search for the end of the FFT frame between
554 		 * sample_len - 1 and sample_len + 2. exp_max is 3
555 		 * bits long and it's the only value on the last
556 		 * byte of the frame so since it'll be smaller than
557 		 * the next byte (the first bin of the next sample)
558 		 * 90% of the time, we can use it as a separator.
559 		 */
560 		if (vdata[i] <= 0x7 && sample_bytes >= sample_len - 1) {
561 
562 			/* Got a frame length within boundaries, there are
563 			 * four scenarios here:
564 			 *
565 			 * a) sample_len -> We got the correct length
566 			 * b) sample_len + 2 -> 2 bytes added around bin[31]
567 			 * c) sample_len - 1 -> The first byte is missing
568 			 * d) sample_len + 1 -> b + c at the same time
569 			 *
570 			 * When MAC adds 2 extra bytes, bin[31] and bin[32]
571 			 * have the same value, so we can use that for further
572 			 * verification in cases b and d.
573 			 */
574 
575 			/* Did we go too far ? If so we couldn't determine
576 			 * this sample's boundaries, discard any further
577 			 * data
578 			 */
579 			if ((sample_bytes > sample_len + 2) ||
580 			   ((sample_bytes > sample_len) &&
581 			   (sample_start[31] != sample_start[32])))
582 				break;
583 
584 			/* See if we got a valid frame by checking the
585 			 * consistency of mag_info fields. This is to
586 			 * prevent from "fixing" a correct frame.
587 			 * Failure is non-fatal, later frames may
588 			 * be valid.
589 			 */
590 			if (!fft_idx_validator(&vdata[i], i)) {
591 				ath_dbg(common, SPECTRAL_SCAN,
592 					"Found valid fft frame at %i\n", i);
593 				got_slen = 1;
594 			}
595 
596 			/* We expect 1 - 2 more bytes */
597 			else if ((sample_start[31] == sample_start[32]) &&
598 				(sample_bytes >= sample_len) &&
599 				(sample_bytes < sample_len + 2) &&
600 				(vdata[i + 1] <= 0x7))
601 				continue;
602 
603 			/* Try to distinguish cases a and c */
604 			else if ((sample_bytes == sample_len - 1) &&
605 				(vdata[i + 1] <= 0x7))
606 				continue;
607 
608 			got_slen = 1;
609 		}
610 
611 		if (got_slen) {
612 			ath_dbg(common, SPECTRAL_SCAN, "FFT frame len: %i\n",
613 				sample_bytes);
614 
615 			/* Only try to fix a frame if it's the only one
616 			 * on the report, else just skip it.
617 			 */
618 			if (sample_bytes != sample_len && len <= fft_len + 2) {
619 				ath_cmn_copy_fft_frame(sample_start,
620 						       sample_buf, sample_len,
621 						       sample_bytes);
622 
623 				ret = fft_handler(rs, spec_priv, sample_buf,
624 						  tsf, freq, chan_type);
625 
626 				if (ret == 0)
627 					RX_STAT_INC(sc, rx_spectral_sample_good);
628 				else
629 					RX_STAT_INC(sc, rx_spectral_sample_err);
630 
631 				memset(sample_buf, 0, SPECTRAL_SAMPLE_MAX_LEN);
632 
633 				/* Mix the received bins to the /dev/random
634 				 * pool
635 				 */
636 				add_device_randomness(sample_buf, num_bins);
637 			}
638 
639 			/* Process a normal frame */
640 			if (sample_bytes == sample_len) {
641 				ret = fft_handler(rs, spec_priv, sample_start,
642 						  tsf, freq, chan_type);
643 
644 				if (ret == 0)
645 					RX_STAT_INC(sc, rx_spectral_sample_good);
646 				else
647 					RX_STAT_INC(sc, rx_spectral_sample_err);
648 
649 				/* Mix the received bins to the /dev/random
650 				 * pool
651 				 */
652 				add_device_randomness(sample_start, num_bins);
653 			}
654 
655 			/* Short report processed, break out of the
656 			 * loop.
657 			 */
658 			if (len <= fft_len + 2)
659 				return 1;
660 
661 			sample_start = &vdata[i + 1];
662 
663 			/* -1 to grab sample_len -1, -2 since
664 			 * they 'll get increased by one. In case
665 			 * of failure try to recover by going byte
666 			 * by byte instead.
667 			 */
668 			if (ret == 0) {
669 				i += num_bins - 2;
670 				sample_bytes = num_bins - 2;
671 			}
672 			got_slen = 0;
673 		}
674 	}
675 
676 	i -= num_bins - 2;
677 	if (len - i != sizeof(struct ath_radar_info))
678 		ath_dbg(common, SPECTRAL_SCAN, "FFT report truncated"
679 						"(bytes left: %i)\n",
680 						len - i);
681 	return 1;
682 }
683 EXPORT_SYMBOL(ath_cmn_process_fft);
684 
685 /*********************/
686 /* spectral_scan_ctl */
687 /*********************/
688 
689 static ssize_t read_file_spec_scan_ctl(struct file *file, char __user *user_buf,
690 				       size_t count, loff_t *ppos)
691 {
692 	struct ath_spec_scan_priv *spec_priv = file->private_data;
693 	char *mode = "";
694 	unsigned int len;
695 
696 	switch (spec_priv->spectral_mode) {
697 	case SPECTRAL_DISABLED:
698 		mode = "disable";
699 		break;
700 	case SPECTRAL_BACKGROUND:
701 		mode = "background";
702 		break;
703 	case SPECTRAL_CHANSCAN:
704 		mode = "chanscan";
705 		break;
706 	case SPECTRAL_MANUAL:
707 		mode = "manual";
708 		break;
709 	}
710 	len = strlen(mode);
711 	return simple_read_from_buffer(user_buf, count, ppos, mode, len);
712 }
713 
714 void ath9k_cmn_spectral_scan_trigger(struct ath_common *common,
715 				 struct ath_spec_scan_priv *spec_priv)
716 {
717 	struct ath_hw *ah = spec_priv->ah;
718 	u32 rxfilter;
719 
720 	if (IS_ENABLED(CONFIG_ATH9K_TX99))
721 		return;
722 
723 	if (!ath9k_hw_ops(ah)->spectral_scan_trigger) {
724 		ath_err(common, "spectrum analyzer not implemented on this hardware\n");
725 		return;
726 	}
727 
728 	if (!spec_priv->spec_config.enabled)
729 		return;
730 
731 	ath_ps_ops(common)->wakeup(common);
732 	rxfilter = ath9k_hw_getrxfilter(ah);
733 	ath9k_hw_setrxfilter(ah, rxfilter |
734 				 ATH9K_RX_FILTER_PHYRADAR |
735 				 ATH9K_RX_FILTER_PHYERR);
736 
737 	/* TODO: usually this should not be neccesary, but for some reason
738 	 * (or in some mode?) the trigger must be called after the
739 	 * configuration, otherwise the register will have its values reset
740 	 * (on my ar9220 to value 0x01002310)
741 	 */
742 	ath9k_cmn_spectral_scan_config(common, spec_priv, spec_priv->spectral_mode);
743 	ath9k_hw_ops(ah)->spectral_scan_trigger(ah);
744 	ath_ps_ops(common)->restore(common);
745 }
746 EXPORT_SYMBOL(ath9k_cmn_spectral_scan_trigger);
747 
748 int ath9k_cmn_spectral_scan_config(struct ath_common *common,
749 			       struct ath_spec_scan_priv *spec_priv,
750 			       enum spectral_mode spectral_mode)
751 {
752 	struct ath_hw *ah = spec_priv->ah;
753 
754 	if (!ath9k_hw_ops(ah)->spectral_scan_trigger) {
755 		ath_err(common, "spectrum analyzer not implemented on this hardware\n");
756 		return -1;
757 	}
758 
759 	switch (spectral_mode) {
760 	case SPECTRAL_DISABLED:
761 		spec_priv->spec_config.enabled = 0;
762 		break;
763 	case SPECTRAL_BACKGROUND:
764 		/* send endless samples.
765 		 * TODO: is this really useful for "background"?
766 		 */
767 		spec_priv->spec_config.endless = 1;
768 		spec_priv->spec_config.enabled = 1;
769 		break;
770 	case SPECTRAL_CHANSCAN:
771 	case SPECTRAL_MANUAL:
772 		spec_priv->spec_config.endless = 0;
773 		spec_priv->spec_config.enabled = 1;
774 		break;
775 	default:
776 		return -1;
777 	}
778 
779 	ath_ps_ops(common)->wakeup(common);
780 	ath9k_hw_ops(ah)->spectral_scan_config(ah, &spec_priv->spec_config);
781 	ath_ps_ops(common)->restore(common);
782 
783 	spec_priv->spectral_mode = spectral_mode;
784 
785 	return 0;
786 }
787 EXPORT_SYMBOL(ath9k_cmn_spectral_scan_config);
788 
789 static ssize_t write_file_spec_scan_ctl(struct file *file,
790 					const char __user *user_buf,
791 					size_t count, loff_t *ppos)
792 {
793 	struct ath_spec_scan_priv *spec_priv = file->private_data;
794 	struct ath_common *common = ath9k_hw_common(spec_priv->ah);
795 	char buf[32];
796 	ssize_t len;
797 
798 	if (IS_ENABLED(CONFIG_ATH9K_TX99))
799 		return -EOPNOTSUPP;
800 
801 	len = min(count, sizeof(buf) - 1);
802 	if (copy_from_user(buf, user_buf, len))
803 		return -EFAULT;
804 
805 	buf[len] = '\0';
806 
807 	if (strncmp("trigger", buf, 7) == 0) {
808 		ath9k_cmn_spectral_scan_trigger(common, spec_priv);
809 	} else if (strncmp("background", buf, 10) == 0) {
810 		ath9k_cmn_spectral_scan_config(common, spec_priv, SPECTRAL_BACKGROUND);
811 		ath_dbg(common, CONFIG, "spectral scan: background mode enabled\n");
812 	} else if (strncmp("chanscan", buf, 8) == 0) {
813 		ath9k_cmn_spectral_scan_config(common, spec_priv, SPECTRAL_CHANSCAN);
814 		ath_dbg(common, CONFIG, "spectral scan: channel scan mode enabled\n");
815 	} else if (strncmp("manual", buf, 6) == 0) {
816 		ath9k_cmn_spectral_scan_config(common, spec_priv, SPECTRAL_MANUAL);
817 		ath_dbg(common, CONFIG, "spectral scan: manual mode enabled\n");
818 	} else if (strncmp("disable", buf, 7) == 0) {
819 		ath9k_cmn_spectral_scan_config(common, spec_priv, SPECTRAL_DISABLED);
820 		ath_dbg(common, CONFIG, "spectral scan: disabled\n");
821 	} else {
822 		return -EINVAL;
823 	}
824 
825 	return count;
826 }
827 
828 static const struct file_operations fops_spec_scan_ctl = {
829 	.read = read_file_spec_scan_ctl,
830 	.write = write_file_spec_scan_ctl,
831 	.open = simple_open,
832 	.owner = THIS_MODULE,
833 	.llseek = default_llseek,
834 };
835 
836 /*************************/
837 /* spectral_short_repeat */
838 /*************************/
839 
840 static ssize_t read_file_spectral_short_repeat(struct file *file,
841 					       char __user *user_buf,
842 					       size_t count, loff_t *ppos)
843 {
844 	struct ath_spec_scan_priv *spec_priv = file->private_data;
845 	char buf[32];
846 	unsigned int len;
847 
848 	len = sprintf(buf, "%d\n", spec_priv->spec_config.short_repeat);
849 	return simple_read_from_buffer(user_buf, count, ppos, buf, len);
850 }
851 
852 static ssize_t write_file_spectral_short_repeat(struct file *file,
853 						const char __user *user_buf,
854 						size_t count, loff_t *ppos)
855 {
856 	struct ath_spec_scan_priv *spec_priv = file->private_data;
857 	unsigned long val;
858 	ssize_t ret;
859 
860 	ret = kstrtoul_from_user(user_buf, count, 0, &val);
861 	if (ret)
862 		return ret;
863 
864 	if (val > 1)
865 		return -EINVAL;
866 
867 	spec_priv->spec_config.short_repeat = val;
868 	return count;
869 }
870 
871 static const struct file_operations fops_spectral_short_repeat = {
872 	.read = read_file_spectral_short_repeat,
873 	.write = write_file_spectral_short_repeat,
874 	.open = simple_open,
875 	.owner = THIS_MODULE,
876 	.llseek = default_llseek,
877 };
878 
879 /******************/
880 /* spectral_count */
881 /******************/
882 
883 static ssize_t read_file_spectral_count(struct file *file,
884 					char __user *user_buf,
885 					size_t count, loff_t *ppos)
886 {
887 	struct ath_spec_scan_priv *spec_priv = file->private_data;
888 	char buf[32];
889 	unsigned int len;
890 
891 	len = sprintf(buf, "%d\n", spec_priv->spec_config.count);
892 	return simple_read_from_buffer(user_buf, count, ppos, buf, len);
893 }
894 
895 static ssize_t write_file_spectral_count(struct file *file,
896 					 const char __user *user_buf,
897 					 size_t count, loff_t *ppos)
898 {
899 	struct ath_spec_scan_priv *spec_priv = file->private_data;
900 	unsigned long val;
901 	ssize_t ret;
902 
903 	ret = kstrtoul_from_user(user_buf, count, 0, &val);
904 	if (ret)
905 		return ret;
906 	if (val > 255)
907 		return -EINVAL;
908 
909 	spec_priv->spec_config.count = val;
910 	return count;
911 }
912 
913 static const struct file_operations fops_spectral_count = {
914 	.read = read_file_spectral_count,
915 	.write = write_file_spectral_count,
916 	.open = simple_open,
917 	.owner = THIS_MODULE,
918 	.llseek = default_llseek,
919 };
920 
921 /*******************/
922 /* spectral_period */
923 /*******************/
924 
925 static ssize_t read_file_spectral_period(struct file *file,
926 					 char __user *user_buf,
927 					 size_t count, loff_t *ppos)
928 {
929 	struct ath_spec_scan_priv *spec_priv = file->private_data;
930 	char buf[32];
931 	unsigned int len;
932 
933 	len = sprintf(buf, "%d\n", spec_priv->spec_config.period);
934 	return simple_read_from_buffer(user_buf, count, ppos, buf, len);
935 }
936 
937 static ssize_t write_file_spectral_period(struct file *file,
938 					  const char __user *user_buf,
939 					  size_t count, loff_t *ppos)
940 {
941 	struct ath_spec_scan_priv *spec_priv = file->private_data;
942 	unsigned long val;
943 	ssize_t ret;
944 
945 	ret = kstrtoul_from_user(user_buf, count, 0, &val);
946 	if (ret)
947 		return ret;
948 
949 	if (val > 255)
950 		return -EINVAL;
951 
952 	spec_priv->spec_config.period = val;
953 	return count;
954 }
955 
956 static const struct file_operations fops_spectral_period = {
957 	.read = read_file_spectral_period,
958 	.write = write_file_spectral_period,
959 	.open = simple_open,
960 	.owner = THIS_MODULE,
961 	.llseek = default_llseek,
962 };
963 
964 /***********************/
965 /* spectral_fft_period */
966 /***********************/
967 
968 static ssize_t read_file_spectral_fft_period(struct file *file,
969 					     char __user *user_buf,
970 					     size_t count, loff_t *ppos)
971 {
972 	struct ath_spec_scan_priv *spec_priv = file->private_data;
973 	char buf[32];
974 	unsigned int len;
975 
976 	len = sprintf(buf, "%d\n", spec_priv->spec_config.fft_period);
977 	return simple_read_from_buffer(user_buf, count, ppos, buf, len);
978 }
979 
980 static ssize_t write_file_spectral_fft_period(struct file *file,
981 					      const char __user *user_buf,
982 					      size_t count, loff_t *ppos)
983 {
984 	struct ath_spec_scan_priv *spec_priv = file->private_data;
985 	unsigned long val;
986 	ssize_t ret;
987 
988 	ret = kstrtoul_from_user(user_buf, count, 0, &val);
989 	if (ret)
990 		return ret;
991 
992 	if (val > 15)
993 		return -EINVAL;
994 
995 	spec_priv->spec_config.fft_period = val;
996 	return count;
997 }
998 
999 static const struct file_operations fops_spectral_fft_period = {
1000 	.read = read_file_spectral_fft_period,
1001 	.write = write_file_spectral_fft_period,
1002 	.open = simple_open,
1003 	.owner = THIS_MODULE,
1004 	.llseek = default_llseek,
1005 };
1006 
1007 /*******************/
1008 /* Relay interface */
1009 /*******************/
1010 
1011 static struct dentry *create_buf_file_handler(const char *filename,
1012 					      struct dentry *parent,
1013 					      umode_t mode,
1014 					      struct rchan_buf *buf,
1015 					      int *is_global)
1016 {
1017 	struct dentry *buf_file;
1018 
1019 	buf_file = debugfs_create_file(filename, mode, parent, buf,
1020 				       &relay_file_operations);
1021 	if (IS_ERR(buf_file))
1022 		return NULL;
1023 
1024 	*is_global = 1;
1025 	return buf_file;
1026 }
1027 
1028 static int remove_buf_file_handler(struct dentry *dentry)
1029 {
1030 	debugfs_remove(dentry);
1031 
1032 	return 0;
1033 }
1034 
1035 static const struct rchan_callbacks rfs_spec_scan_cb = {
1036 	.create_buf_file = create_buf_file_handler,
1037 	.remove_buf_file = remove_buf_file_handler,
1038 };
1039 
1040 /*********************/
1041 /* Debug Init/Deinit */
1042 /*********************/
1043 
1044 void ath9k_cmn_spectral_deinit_debug(struct ath_spec_scan_priv *spec_priv)
1045 {
1046 	if (spec_priv->rfs_chan_spec_scan) {
1047 		relay_close(spec_priv->rfs_chan_spec_scan);
1048 		spec_priv->rfs_chan_spec_scan = NULL;
1049 	}
1050 }
1051 EXPORT_SYMBOL(ath9k_cmn_spectral_deinit_debug);
1052 
1053 void ath9k_cmn_spectral_init_debug(struct ath_spec_scan_priv *spec_priv,
1054 				   struct dentry *debugfs_phy)
1055 {
1056 	spec_priv->rfs_chan_spec_scan = relay_open("spectral_scan",
1057 					    debugfs_phy,
1058 					    1024, 256, &rfs_spec_scan_cb,
1059 					    NULL);
1060 	if (!spec_priv->rfs_chan_spec_scan)
1061 		return;
1062 
1063 	debugfs_create_file("spectral_scan_ctl",
1064 			    0600,
1065 			    debugfs_phy, spec_priv,
1066 			    &fops_spec_scan_ctl);
1067 	debugfs_create_file("spectral_short_repeat",
1068 			    0600,
1069 			    debugfs_phy, spec_priv,
1070 			    &fops_spectral_short_repeat);
1071 	debugfs_create_file("spectral_count",
1072 			    0600,
1073 			    debugfs_phy, spec_priv,
1074 			    &fops_spectral_count);
1075 	debugfs_create_file("spectral_period",
1076 			    0600,
1077 			    debugfs_phy, spec_priv,
1078 			    &fops_spectral_period);
1079 	debugfs_create_file("spectral_fft_period",
1080 			    0600,
1081 			    debugfs_phy, spec_priv,
1082 			    &fops_spectral_fft_period);
1083 }
1084 EXPORT_SYMBOL(ath9k_cmn_spectral_init_debug);
1085