// SPDX-License-Identifier: ISC
/*
 * Copyright (c) 2013-2017 Qualcomm Atheros, Inc.
 */

#include <linux/relay.h>
#include "core.h"
#include "debug.h"
#include "wmi-ops.h"

static void send_fft_sample(struct ath10k *ar,
                            const struct fft_sample_tlv *fft_sample_tlv)
{
        int length;

        if (!ar->spectral.rfs_chan_spec_scan)
                return;

        length = __be16_to_cpu(fft_sample_tlv->length) +
                 sizeof(*fft_sample_tlv);
        relay_write(ar->spectral.rfs_chan_spec_scan, fft_sample_tlv, length);
}

static uint8_t get_max_exp(s8 max_index, u16 max_magnitude, size_t bin_len,
                           u8 *data)
{
        int dc_pos;
        u8 max_exp;

        dc_pos = bin_len / 2;

        /* peak index outside of bins */
        if (dc_pos < max_index || -dc_pos >= max_index)
                return 0;

        for (max_exp = 0; max_exp < 8; max_exp++) {
                if (data[dc_pos + max_index] == (max_magnitude >> max_exp))
                        break;
        }

        /* max_exp not found */
        if (data[dc_pos + max_index] != (max_magnitude >> max_exp))
                return 0;

        return max_exp;
}

static inline size_t ath10k_spectral_fix_bin_size(struct ath10k *ar,
                                                  size_t bin_len)
{
        /* some chipsets reports bin size as 2^n bytes + 'm' bytes in
         * report mode 2. First 2^n bytes carries inband tones and last
         * 'm' bytes carries band edge detection data mainly used in
         * radar detection purpose. Strip last 'm' bytes to make bin size
         * as a valid one. 'm' can take possible values of 4, 12.
         */
        if (!is_power_of_2(bin_len))
                bin_len -= ar->hw_params.spectral_bin_discard;

        return bin_len;
}

int ath10k_spectral_process_fft(struct ath10k *ar,
                                struct wmi_phyerr_ev_arg *phyerr,
                                const struct phyerr_fft_report *fftr,
                                size_t bin_len, u64 tsf)
{
        struct fft_sample_ath10k *fft_sample;
        u8 buf[sizeof(*fft_sample) + SPECTRAL_ATH10K_MAX_NUM_BINS];
        u16 freq1, freq2, total_gain_db, base_pwr_db, length, peak_mag;
        u32 reg0, reg1;
        u8 chain_idx, *bins;
        int dc_pos;

        fft_sample = (struct fft_sample_ath10k *)&buf;

        bin_len = ath10k_spectral_fix_bin_size(ar, bin_len);

        if (bin_len < 64 || bin_len > SPECTRAL_ATH10K_MAX_NUM_BINS)
                return -EINVAL;

        reg0 = __le32_to_cpu(fftr->reg0);
        reg1 = __le32_to_cpu(fftr->reg1);

        length = sizeof(*fft_sample) - sizeof(struct fft_sample_tlv) + bin_len;
        fft_sample->tlv.type = ATH_FFT_SAMPLE_ATH10K;
        fft_sample->tlv.length = __cpu_to_be16(length);

        /* TODO: there might be a reason why the hardware reports 20/40/80 MHz,
         * but the results/plots suggest that its actually 22/44/88 MHz.
         */
        switch (phyerr->chan_width_mhz) {
        case 20:
                fft_sample->chan_width_mhz = 22;
                break;
        case 40:
                fft_sample->chan_width_mhz = 44;
                break;
        case 80:
                /* TODO: As experiments with an analogue sender and various
                 * configurations (fft-sizes of 64/128/256 and 20/40/80 Mhz)
                 * show, the particular configuration of 80 MHz/64 bins does
                 * not match with the other samples at all. Until the reason
                 * for that is found, don't report these samples.
                 */
                if (bin_len == 64)
                        return -EINVAL;
                fft_sample->chan_width_mhz = 88;
                break;
        default:
                fft_sample->chan_width_mhz = phyerr->chan_width_mhz;
        }

        fft_sample->relpwr_db = MS(reg1, SEARCH_FFT_REPORT_REG1_RELPWR_DB);
        fft_sample->avgpwr_db = MS(reg1, SEARCH_FFT_REPORT_REG1_AVGPWR_DB);

        peak_mag = MS(reg1, SEARCH_FFT_REPORT_REG1_PEAK_MAG);
        fft_sample->max_magnitude = __cpu_to_be16(peak_mag);
        fft_sample->max_index = MS(reg0, SEARCH_FFT_REPORT_REG0_PEAK_SIDX);
        fft_sample->rssi = phyerr->rssi_combined;

        total_gain_db = MS(reg0, SEARCH_FFT_REPORT_REG0_TOTAL_GAIN_DB);
        base_pwr_db = MS(reg0, SEARCH_FFT_REPORT_REG0_BASE_PWR_DB);
        fft_sample->total_gain_db = __cpu_to_be16(total_gain_db);
        fft_sample->base_pwr_db = __cpu_to_be16(base_pwr_db);

        freq1 = phyerr->freq1;
        freq2 = phyerr->freq2;
        fft_sample->freq1 = __cpu_to_be16(freq1);
        fft_sample->freq2 = __cpu_to_be16(freq2);

        chain_idx = MS(reg0, SEARCH_FFT_REPORT_REG0_FFT_CHN_IDX);

        fft_sample->noise = __cpu_to_be16(phyerr->nf_chains[chain_idx]);

        bins = (u8 *)fftr;
        bins += sizeof(*fftr) + ar->hw_params.spectral_bin_offset;

        fft_sample->tsf = __cpu_to_be64(tsf);

        /* max_exp has been directly reported by previous hardware (ath9k),
         * maybe its possible to get it by other means?
         */
        fft_sample->max_exp = get_max_exp(fft_sample->max_index, peak_mag,
                                          bin_len, bins);

        memcpy(fft_sample->data, bins, bin_len);

        /* DC value (value in the middle) is the blind spot of the spectral
         * sample and invalid, interpolate it.
         */
        dc_pos = bin_len / 2;
        fft_sample->data[dc_pos] = (fft_sample->data[dc_pos + 1] +
                                    fft_sample->data[dc_pos - 1]) / 2;

        send_fft_sample(ar, &fft_sample->tlv);

        return 0;
}

static struct ath10k_vif *ath10k_get_spectral_vdev(struct ath10k *ar)
{
        struct ath10k_vif *arvif;

        lockdep_assert_held(&ar->conf_mutex);

        if (list_empty(&ar->arvifs))
                return NULL;

        /* if there already is a vif doing spectral, return that. */
        list_for_each_entry(arvif, &ar->arvifs, list)
                if (arvif->spectral_enabled)
                        return arvif;

        /* otherwise, return the first vif. */
        return list_first_entry(&ar->arvifs, typeof(*arvif), list);
}

static int ath10k_spectral_scan_trigger(struct ath10k *ar)
{
        struct ath10k_vif *arvif;
        int res;
        int vdev_id;

        lockdep_assert_held(&ar->conf_mutex);

        arvif = ath10k_get_spectral_vdev(ar);
        if (!arvif)
                return -ENODEV;
        vdev_id = arvif->vdev_id;

        if (ar->spectral.mode == SPECTRAL_DISABLED)
                return 0;

        res = ath10k_wmi_vdev_spectral_enable(ar, vdev_id,
                                              WMI_SPECTRAL_TRIGGER_CMD_CLEAR,
                                              WMI_SPECTRAL_ENABLE_CMD_ENABLE);
        if (res < 0)
                return res;

        res = ath10k_wmi_vdev_spectral_enable(ar, vdev_id,
                                              WMI_SPECTRAL_TRIGGER_CMD_TRIGGER,
                                              WMI_SPECTRAL_ENABLE_CMD_ENABLE);
        if (res < 0)
                return res;

        return 0;
}

static int ath10k_spectral_scan_config(struct ath10k *ar,
                                       enum ath10k_spectral_mode mode)
{
        struct wmi_vdev_spectral_conf_arg arg;
        struct ath10k_vif *arvif;
        int vdev_id, count, res = 0;

        lockdep_assert_held(&ar->conf_mutex);

        arvif = ath10k_get_spectral_vdev(ar);
        if (!arvif)
                return -ENODEV;

        vdev_id = arvif->vdev_id;

        arvif->spectral_enabled = (mode != SPECTRAL_DISABLED);
        ar->spectral.mode = mode;

        res = ath10k_wmi_vdev_spectral_enable(ar, vdev_id,
                                              WMI_SPECTRAL_TRIGGER_CMD_CLEAR,
                                              WMI_SPECTRAL_ENABLE_CMD_DISABLE);
        if (res < 0) {
                ath10k_warn(ar, "failed to enable spectral scan: %d\n", res);
                return res;
        }

        if (mode == SPECTRAL_DISABLED)
                return 0;

        if (mode == SPECTRAL_BACKGROUND)
                count = WMI_SPECTRAL_COUNT_DEFAULT;
        else
                count = max_t(u8, 1, ar->spectral.config.count);

        arg.vdev_id = vdev_id;
        arg.scan_count = count;
        arg.scan_period = WMI_SPECTRAL_PERIOD_DEFAULT;
        arg.scan_priority = WMI_SPECTRAL_PRIORITY_DEFAULT;
        arg.scan_fft_size = ar->spectral.config.fft_size;
        arg.scan_gc_ena = WMI_SPECTRAL_GC_ENA_DEFAULT;
        arg.scan_restart_ena = WMI_SPECTRAL_RESTART_ENA_DEFAULT;
        arg.scan_noise_floor_ref = WMI_SPECTRAL_NOISE_FLOOR_REF_DEFAULT;
        arg.scan_init_delay = WMI_SPECTRAL_INIT_DELAY_DEFAULT;
        arg.scan_nb_tone_thr = WMI_SPECTRAL_NB_TONE_THR_DEFAULT;
        arg.scan_str_bin_thr = WMI_SPECTRAL_STR_BIN_THR_DEFAULT;
        arg.scan_wb_rpt_mode = WMI_SPECTRAL_WB_RPT_MODE_DEFAULT;
        arg.scan_rssi_rpt_mode = WMI_SPECTRAL_RSSI_RPT_MODE_DEFAULT;
        arg.scan_rssi_thr = WMI_SPECTRAL_RSSI_THR_DEFAULT;
        arg.scan_pwr_format = WMI_SPECTRAL_PWR_FORMAT_DEFAULT;
        arg.scan_rpt_mode = WMI_SPECTRAL_RPT_MODE_DEFAULT;
        arg.scan_bin_scale = WMI_SPECTRAL_BIN_SCALE_DEFAULT;
        arg.scan_dbm_adj = WMI_SPECTRAL_DBM_ADJ_DEFAULT;
        arg.scan_chn_mask = WMI_SPECTRAL_CHN_MASK_DEFAULT;

        res = ath10k_wmi_vdev_spectral_conf(ar, &arg);
        if (res < 0) {
                ath10k_warn(ar, "failed to configure spectral scan: %d\n", res);
                return res;
        }

        return 0;
}

static ssize_t read_file_spec_scan_ctl(struct file *file, char __user *user_buf,
                                       size_t count, loff_t *ppos)
{
        struct ath10k *ar = file->private_data;
        char *mode = "";
        size_t len;
        enum ath10k_spectral_mode spectral_mode;

        mutex_lock(&ar->conf_mutex);
        spectral_mode = ar->spectral.mode;
        mutex_unlock(&ar->conf_mutex);

        switch (spectral_mode) {
        case SPECTRAL_DISABLED:
                mode = "disable";
                break;
        case SPECTRAL_BACKGROUND:
                mode = "background";
                break;
        case SPECTRAL_MANUAL:
                mode = "manual";
                break;
        }

        len = strlen(mode);
        return simple_read_from_buffer(user_buf, count, ppos, mode, len);
}

static ssize_t write_file_spec_scan_ctl(struct file *file,
                                        const char __user *user_buf,
                                        size_t count, loff_t *ppos)
{
        struct ath10k *ar = file->private_data;
        char buf[32];
        ssize_t len;
        int res;

        len = min(count, sizeof(buf) - 1);
        if (copy_from_user(buf, user_buf, len))
                return -EFAULT;

        buf[len] = '\0';

        mutex_lock(&ar->conf_mutex);

        if (strncmp("trigger", buf, 7) == 0) {
                if (ar->spectral.mode == SPECTRAL_MANUAL ||
                    ar->spectral.mode == SPECTRAL_BACKGROUND) {
                        /* reset the configuration to adopt possibly changed
                         * debugfs parameters
                         */
                        res = ath10k_spectral_scan_config(ar,
                                                          ar->spectral.mode);
                        if (res < 0) {
                                ath10k_warn(ar, "failed to reconfigure spectral scan: %d\n",
                                            res);
                        }
                        res = ath10k_spectral_scan_trigger(ar);
                        if (res < 0) {
                                ath10k_warn(ar, "failed to trigger spectral scan: %d\n",
                                            res);
                        }
                } else {
                        res = -EINVAL;
                }
        } else if (strncmp("background", buf, 10) == 0) {
                res = ath10k_spectral_scan_config(ar, SPECTRAL_BACKGROUND);
        } else if (strncmp("manual", buf, 6) == 0) {
                res = ath10k_spectral_scan_config(ar, SPECTRAL_MANUAL);
        } else if (strncmp("disable", buf, 7) == 0) {
                res = ath10k_spectral_scan_config(ar, SPECTRAL_DISABLED);
        } else {
                res = -EINVAL;
        }

        mutex_unlock(&ar->conf_mutex);

        if (res < 0)
                return res;

        return count;
}

static const struct file_operations fops_spec_scan_ctl = {
        .read = read_file_spec_scan_ctl,
        .write = write_file_spec_scan_ctl,
        .open = simple_open,
        .owner = THIS_MODULE,
        .llseek = default_llseek,
};

static ssize_t read_file_spectral_count(struct file *file,
                                        char __user *user_buf,
                                        size_t count, loff_t *ppos)
{
        struct ath10k *ar = file->private_data;
        char buf[32];
        size_t len;
        u8 spectral_count;

        mutex_lock(&ar->conf_mutex);
        spectral_count = ar->spectral.config.count;
        mutex_unlock(&ar->conf_mutex);

        len = sprintf(buf, "%d\n", spectral_count);
        return simple_read_from_buffer(user_buf, count, ppos, buf, len);
}

static ssize_t write_file_spectral_count(struct file *file,
                                         const char __user *user_buf,
                                         size_t count, loff_t *ppos)
{
        struct ath10k *ar = file->private_data;
        unsigned long val;
        ssize_t ret;

        ret = kstrtoul_from_user(user_buf, count, 0, &val);
        if (ret)
                return ret;

        if (val > 255)
                return -EINVAL;

        mutex_lock(&ar->conf_mutex);
        ar->spectral.config.count = val;
        mutex_unlock(&ar->conf_mutex);

        return count;
}

static const struct file_operations fops_spectral_count = {
        .read = read_file_spectral_count,
        .write = write_file_spectral_count,
        .open = simple_open,
        .owner = THIS_MODULE,
        .llseek = default_llseek,
};

static ssize_t read_file_spectral_bins(struct file *file,
                                       char __user *user_buf,
                                       size_t count, loff_t *ppos)
{
        struct ath10k *ar = file->private_data;
        char buf[32];
        unsigned int bins, fft_size, bin_scale;
        size_t len;

        mutex_lock(&ar->conf_mutex);

        fft_size = ar->spectral.config.fft_size;
        bin_scale = WMI_SPECTRAL_BIN_SCALE_DEFAULT;
        bins = 1 << (fft_size - bin_scale);

        mutex_unlock(&ar->conf_mutex);

        len = sprintf(buf, "%d\n", bins);
        return simple_read_from_buffer(user_buf, count, ppos, buf, len);
}

static ssize_t write_file_spectral_bins(struct file *file,
                                        const char __user *user_buf,
                                        size_t count, loff_t *ppos)
{
        struct ath10k *ar = file->private_data;
        unsigned long val;
        ssize_t ret;

        ret = kstrtoul_from_user(user_buf, count, 0, &val);
        if (ret)
                return ret;

        if (val < 64 || val > SPECTRAL_ATH10K_MAX_NUM_BINS)
                return -EINVAL;

        if (!is_power_of_2(val))
                return -EINVAL;

        mutex_lock(&ar->conf_mutex);
        ar->spectral.config.fft_size = ilog2(val);
        ar->spectral.config.fft_size += WMI_SPECTRAL_BIN_SCALE_DEFAULT;
        mutex_unlock(&ar->conf_mutex);

        return count;
}

static const struct file_operations fops_spectral_bins = {
        .read = read_file_spectral_bins,
        .write = write_file_spectral_bins,
        .open = simple_open,
        .owner = THIS_MODULE,
        .llseek = default_llseek,
};

static struct dentry *create_buf_file_handler(const char *filename,
                                              struct dentry *parent,
                                              umode_t mode,
                                              struct rchan_buf *buf,
                                              int *is_global)
{
        struct dentry *buf_file;

        buf_file = debugfs_create_file(filename, mode, parent, buf,
                                       &relay_file_operations);
        if (IS_ERR(buf_file))
                return NULL;

        *is_global = 1;
        return buf_file;
}

static int remove_buf_file_handler(struct dentry *dentry)
{
        debugfs_remove(dentry);

        return 0;
}

static const struct rchan_callbacks rfs_spec_scan_cb = {
        .create_buf_file = create_buf_file_handler,
        .remove_buf_file = remove_buf_file_handler,
};

int ath10k_spectral_start(struct ath10k *ar)
{
        struct ath10k_vif *arvif;

        lockdep_assert_held(&ar->conf_mutex);

        list_for_each_entry(arvif, &ar->arvifs, list)
                arvif->spectral_enabled = 0;

        ar->spectral.mode = SPECTRAL_DISABLED;
        ar->spectral.config.count = WMI_SPECTRAL_COUNT_DEFAULT;
        ar->spectral.config.fft_size = WMI_SPECTRAL_FFT_SIZE_DEFAULT;

        return 0;
}

int ath10k_spectral_vif_stop(struct ath10k_vif *arvif)
{
        if (!arvif->spectral_enabled)
                return 0;

        return ath10k_spectral_scan_config(arvif->ar, SPECTRAL_DISABLED);
}

int ath10k_spectral_create(struct ath10k *ar)
{
        /* The buffer size covers whole channels in dual bands up to 128 bins.
         * Scan with bigger than 128 bins needs to be run on single band each.
         */
        ar->spectral.rfs_chan_spec_scan = relay_open("spectral_scan",
                                                     ar->debug.debugfs_phy,
                                                     1140, 2500,
                                                     &rfs_spec_scan_cb, NULL);
        debugfs_create_file("spectral_scan_ctl",
                            0600,
                            ar->debug.debugfs_phy, ar,
                            &fops_spec_scan_ctl);
        debugfs_create_file("spectral_count",
                            0600,
                            ar->debug.debugfs_phy, ar,
                            &fops_spectral_count);
        debugfs_create_file("spectral_bins",
                            0600,
                            ar->debug.debugfs_phy, ar,
                            &fops_spectral_bins);

        return 0;
}

void ath10k_spectral_destroy(struct ath10k *ar)
{
        if (ar->spectral.rfs_chan_spec_scan) {
                relay_close(ar->spectral.rfs_chan_spec_scan);
                ar->spectral.rfs_chan_spec_scan = NULL;
        }
}