diff --git a/drivers/net/wireless/ath/ath9k/common-spectral.c b/drivers/net/wireless/ath/ath9k/common-spectral.c
index 12db498..51ab396 100644
--- a/drivers/net/wireless/ath/ath9k/common-spectral.c
+++ b/drivers/net/wireless/ath/ath9k/common-spectral.c
@@ -36,6 +36,104 @@ static void ath_debug_send_fft_sample(struct ath_spec_scan_priv *spec_priv,
 	relay_write(spec_priv->rfs_chan_spec_scan, fft_sample_tlv, length);
 }
 
+typedef int (ath_cmn_fft_idx_validator) (u8 *sample_end, int bytes_read);
+
+static int
+ath_cmn_max_idx_verify_ht20_fft(u8 *sample_end, int bytes_read)
+{
+	struct ath_ht20_mag_info *mag_info;
+	u8 *sample;
+	u16 max_magnitude;
+	u8 max_index;
+	u8 max_exp;
+
+	/* Sanity check so that we don't read outside the read
+	 * buffer
+	 */
+	if (bytes_read < SPECTRAL_HT20_SAMPLE_LEN - 1)
+		return -1;
+
+	mag_info = (struct ath_ht20_mag_info *) (sample_end -
+				sizeof(struct ath_ht20_mag_info) + 1);
+
+	sample = sample_end - SPECTRAL_HT20_SAMPLE_LEN + 1;
+
+	max_index = spectral_max_index(mag_info->all_bins,
+				       SPECTRAL_HT20_NUM_BINS);
+	max_magnitude = spectral_max_magnitude(mag_info->all_bins);
+
+	max_exp = mag_info->max_exp & 0xf;
+
+	/* Don't try to read something outside the read buffer
+	 * in case of a missing byte (so bins[0] will be outside
+	 * the read buffer)
+	 */
+	if (bytes_read < SPECTRAL_HT20_SAMPLE_LEN && max_index < 1)
+		return -1;
+
+	if (sample[max_index] != (max_magnitude >> max_exp))
+		return -1;
+	else
+		return 0;
+}
+
+static int
+ath_cmn_max_idx_verify_ht20_40_fft(u8 *sample_end, int bytes_read)
+{
+	struct ath_ht20_40_mag_info *mag_info;
+	u8 *sample;
+	u16 lower_mag, upper_mag;
+	u8 lower_max_index, upper_max_index;
+	u8 max_exp;
+	int dc_pos = SPECTRAL_HT20_40_NUM_BINS / 2;
+
+	/* Sanity check so that we don't read outside the read
+	 * buffer
+	 */
+	if (bytes_read < SPECTRAL_HT20_40_SAMPLE_LEN - 1)
+		return -1;
+
+	mag_info = (struct ath_ht20_40_mag_info *) (sample_end -
+				sizeof(struct ath_ht20_40_mag_info) + 1);
+
+	sample = sample_end - SPECTRAL_HT20_40_SAMPLE_LEN + 1;
+
+	lower_mag = spectral_max_magnitude(mag_info->lower_bins);
+	lower_max_index = spectral_max_index(mag_info->lower_bins,
+					     SPECTRAL_HT20_40_NUM_BINS);
+
+	upper_mag = spectral_max_magnitude(mag_info->upper_bins);
+	upper_max_index = spectral_max_index(mag_info->upper_bins,
+					     SPECTRAL_HT20_40_NUM_BINS);
+
+	max_exp = mag_info->max_exp & 0xf;
+
+	/* Don't try to read something outside the read buffer
+	 * in case of a missing byte (so bins[0] will be outside
+	 * the read buffer)
+	 */
+	if (bytes_read < SPECTRAL_HT20_40_SAMPLE_LEN &&
+	   ((upper_max_index < 1) || (lower_max_index < 1)))
+		return -1;
+
+	/* Some time hardware messes up the index and adds
+	 * the index of the middle point (dc_pos). Try to fix it.
+	 */
+	if ((upper_max_index - dc_pos > 0) &&
+	   (sample[upper_max_index] == (upper_mag >> max_exp)))
+		upper_max_index -= dc_pos;
+
+	if ((lower_max_index - dc_pos > 0) &&
+	   (sample[lower_max_index - dc_pos] == (lower_mag >> max_exp)))
+		lower_max_index -= dc_pos;
+
+	if ((sample[upper_max_index + dc_pos] != (upper_mag >> max_exp)) ||
+	   (sample[lower_max_index] != (lower_mag >> max_exp)))
+		return -1;
+	else
+		return 0;
+}
+
 typedef int (ath_cmn_fft_sample_handler) (struct ath_rx_status *rs,
 			struct ath_spec_scan_priv *spec_priv,
 			u8 *sample_buf, u64 tsf, u16 freq, int chan_type);
@@ -349,8 +447,14 @@ int ath_cmn_process_fft(struct ath_spec_scan_priv *spec_priv, struct ieee80211_h
 	u8 num_bins, *vdata = (u8 *)hdr;
 	struct ath_radar_info *radar_info;
 	int len = rs->rs_datalen;
+	int i;
+	int got_slen = 0;
+	u8  *sample_start;
+	int sample_bytes = 0;
+	int ret = 0;
 	u16 fft_len, sample_len, freq = ah->curchan->chan->center_freq;
 	enum nl80211_channel_type chan_type;
+	ath_cmn_fft_idx_validator *fft_idx_validator;
 	ath_cmn_fft_sample_handler *fft_handler;
 
 	/* AR9280 and before report via ATH9K_PHYERR_RADAR, AR93xx and newer
@@ -375,47 +479,150 @@ int ath_cmn_process_fft(struct ath_spec_scan_priv *spec_priv, struct ieee80211_h
 		fft_len = SPECTRAL_HT20_40_TOTAL_DATA_LEN;
 		sample_len = SPECTRAL_HT20_40_SAMPLE_LEN;
 		num_bins = SPECTRAL_HT20_40_NUM_BINS;
+		fft_idx_validator = &ath_cmn_max_idx_verify_ht20_40_fft;
 		fft_handler = &ath_cmn_process_ht20_40_fft;
 	} else {
 		fft_len = SPECTRAL_HT20_TOTAL_DATA_LEN;
 		sample_len = SPECTRAL_HT20_SAMPLE_LEN;
 		num_bins = SPECTRAL_HT20_NUM_BINS;
+		fft_idx_validator = ath_cmn_max_idx_verify_ht20_fft;
 		fft_handler = &ath_cmn_process_ht20_fft;
 	}
 
-	/* Variation in the data length is possible and will be fixed later */
-	if ((len > fft_len + 2) || (len < fft_len - 1))
-		return 1;
+	ath_dbg(common, SPECTRAL_SCAN, "Got radar dump bw_info: 0x%X,"
+					"len: %i fft_len: %i\n",
+					radar_info->pulse_bw_info,
+					len,
+					fft_len);
+	sample_start = vdata;
+	for (i = 0; i < len - 2; i++) {
+		sample_bytes++;
+
+		/* Only a single sample received, no need to look
+		 * for the sample's end, do the correction based
+		 * on the packet's length instead. Note that hw
+		 * will always put the radar_info structure on
+		 * the end.
+		 */
+		if (len <= fft_len + 2) {
+			sample_bytes = len - sizeof(struct ath_radar_info);
+			got_slen = 1;
+		}
 
-	switch (len - fft_len) {
-	case 0:
-		/* length correct, nothing to do. */
-		memcpy(sample_buf, vdata, sample_len);
-		break;
-	case -1:
-		/* first byte missing, duplicate it. */
-		memcpy(&sample_buf[1], vdata, sample_len - 1);
-		sample_buf[0] = vdata[0];
-		break;
-	case 2:
-		/* MAC added 2 extra bytes at bin 30 and 32, remove them. */
-		memcpy(sample_buf, vdata, 30);
-		sample_buf[30] = vdata[31];
-		memcpy(&sample_buf[31], &vdata[33], sample_len - 31);
-		break;
-	case 1:
-		/* MAC added 2 extra bytes AND first byte is missing. */
-		sample_buf[0] = vdata[0];
-		memcpy(&sample_buf[1], vdata, 30);
-		sample_buf[31] = vdata[31];
-		memcpy(&sample_buf[32], &vdata[33], sample_len - 32);
-		break;
-	default:
-		return 1;
-	}
+		/* Search for the end of the FFT frame between
+		 * sample_len - 1 and sample_len + 2. exp_max is 3
+		 * bits long and it's the only value on the last
+		 * byte of the frame so since it'll be smaller than
+		 * the next byte (the first bin of the next sample)
+		 * 90% of the time, we can use it as a separator.
+		 */
+		if (vdata[i] <= 0x7 && sample_bytes >= sample_len - 1) {
+
+			/* Got a frame length within boundaries, there are
+			 * four scenarios here:
+			 *
+			 * a) sample_len -> We got the correct length
+			 * b) sample_len + 2 -> 2 bytes added around bin[31]
+			 * c) sample_len - 1 -> The first byte is missing
+			 * d) sample_len + 1 -> b + c at the same time
+			 *
+			 * When MAC adds 2 extra bytes, bin[31] and bin[32]
+			 * have the same value, so we can use that for further
+			 * verification in cases b and d.
+			 */
+
+			/* Did we go too far ? If so we couldn't determine
+			 * this sample's boundaries, discard any further
+			 * data
+			 */
+			if ((sample_bytes > sample_len + 2) ||
+			   ((sample_bytes > sample_len) &&
+			   (sample_start[31] != sample_start[32])))
+				break;
+
+			/* See if we got a valid frame by checking the
+			 * consistency of mag_info fields. This is to
+			 * prevent from "fixing" a correct frame.
+			 * Failure is non-fatal, later frames may
+			 * be valid.
+			 */
+			if (!fft_idx_validator(&vdata[i], i)) {
+				ath_dbg(common, SPECTRAL_SCAN,
+					"Found valid fft frame at %i\n", i);
+				got_slen = 1;
+			}
 
-	fft_handler(rs, spec_priv, sample_buf, tsf, freq, chan_type);
+			/* We expect 1 - 2 more bytes */
+			else if ((sample_start[31] == sample_start[32]) &&
+				(sample_bytes >= sample_len) &&
+				(sample_bytes < sample_len + 2) &&
+				(vdata[i + 1] <= 0x7))
+				continue;
+
+			/* Try to distinguish cases a and c */
+			else if ((sample_bytes == sample_len - 1) &&
+				(vdata[i + 1] <= 0x7))
+				continue;
+
+			got_slen = 1;
+		}
+
+		if (got_slen) {
+			ath_dbg(common, SPECTRAL_SCAN, "FFT frame len: %i\n",
+				sample_bytes);
+			switch (sample_bytes - sample_len) {
+			case -1:
+				/* First byte missing */
+				memcpy(&sample_buf[1], sample_start,
+				       sample_len - 1);
+				break;
+			case 0:
+				/* Length correct, nothing to do. */
+				memcpy(sample_buf, sample_start, sample_len);
+				break;
+			case 1:
+				/* MAC added 2 extra bytes AND first byte
+				 * is missing.
+				 */
+				memcpy(&sample_buf[1], sample_start, 30);
+				sample_buf[31] = sample_start[31];
+				memcpy(&sample_buf[32], &sample_start[33],
+				       sample_len - 32);
+				break;
+			case 2:
+				/* MAC added 2 extra bytes at bin 30 and 32,
+				 * remove them.
+				 */
+				memcpy(sample_buf, sample_start, 30);
+				sample_buf[30] = sample_start[31];
+				memcpy(&sample_buf[31], &sample_start[33],
+				       sample_len - 31);
+				break;
+			default:
+				break;
+			}
+
+			ret = fft_handler(rs, spec_priv, sample_buf, tsf,
+							freq, chan_type);
+			memset(sample_buf, 0, SPECTRAL_SAMPLE_MAX_LEN);
+			sample_start = &vdata[i + 1];
+			/* -1 to grab sample_len -1, -2 since
+			 * they 'll get increased by one. In case
+			 * of failure try to recover by going byte
+			 * by byte instead. */
+			if (ret == 0) {
+				i += num_bins - 2;
+				sample_bytes = num_bins - 2;
+			}
+			got_slen = 0;
+		}
+	}
 
+	i -= num_bins - 2;
+	if (len - i != sizeof(struct ath_radar_info))
+		ath_dbg(common, SPECTRAL_SCAN, "FFT report truncated"
+						"(bytes left: %i)\n",
+						len - i);
 	return 1;
 }
 EXPORT_SYMBOL(ath_cmn_process_fft);
