path: root/drivers/net/wireless/ath/ath9k/common-spectral.c

/*
 * Copyright (c) 2013 Qualcomm Atheros, Inc.
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <linux/relay.h>
#include <linux/random.h>
#include "ath9k.h"

static s8 fix_rssi_inv_only(u8 rssi_val)
{
	if (rssi_val == 128)
		rssi_val = 0;
	return (s8) rssi_val;
}

static void ath_debug_send_fft_sample(struct ath_spec_scan_priv *spec_priv,
				      struct fft_sample_tlv *fft_sample_tlv)
{
	int length;
	if (!spec_priv->rfs_chan_spec_scan)
		return;

	length = __be16_to_cpu(fft_sample_tlv->length) +
		 sizeof(*fft_sample_tlv);
	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_ht20(mag_info->all_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] & 0xf8) != ((max_magnitude >> max_exp) & 0xf8))
		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_ht40(mag_info->lower_bins);

	upper_mag = spectral_max_magnitude(mag_info->upper_bins);
	upper_max_index = spectral_max_index_ht40(mag_info->upper_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;

	if (((sample[upper_max_index + dc_pos] & 0xf8) !=
	     ((upper_mag >> max_exp) & 0xf8)) ||
	    ((sample[lower_max_index] & 0xf8) !=
	     ((lower_mag >> max_exp) & 0xf8)))
		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);

static int
ath_cmn_process_ht20_fft(struct ath_rx_status *rs,
			struct ath_spec_scan_priv *spec_priv,
			u8 *sample_buf,
			u64 tsf, u16 freq, int chan_type)
{
	struct fft_sample_ht20 fft_sample_20;
	struct ath_common *common = ath9k_hw_common(spec_priv->ah);
	struct ath_hw *ah = spec_priv->ah;
	struct ath_ht20_mag_info *mag_info;
	struct fft_sample_tlv *tlv;
	int i = 0;
	int ret = 0;
	int dc_pos = SPECTRAL_HT20_NUM_BINS / 2;
	u16 magnitude, tmp_mag, length;
	u8 max_index, bitmap_w, max_exp