/*
 * NXP Wireless LAN device driver: 802.11h
 *
 * Copyright 2011-2020 NXP
 *
 * This software file (the "File") is distributed by NXP
 * under the terms of the GNU General Public License Version 2, June 1991
 * (the "License").  You may use, redistribute and/or modify this File in
 * accordance with the terms and conditions of the License, a copy of which
 * is available by writing to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA or on the
 * worldwide web at http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt.
 *
 * THE FILE IS DISTRIBUTED AS-IS, WITHOUT WARRANTY OF ANY KIND, AND THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE
 * ARE EXPRESSLY DISCLAIMED.  The License provides additional details about
 * this warranty disclaimer.
 */

#include "main.h"
#include "fw.h"


void mwifiex_init_11h_params(struct mwifiex_private *priv)
{
        priv->state_11h.is_11h_enabled = true;
        priv->state_11h.is_11h_active = false;
}

inline int mwifiex_is_11h_active(struct mwifiex_private *priv)
{
        return priv->state_11h.is_11h_active;
}
/* This function appends 11h info to a buffer while joining an
 * infrastructure BSS
 */
static void
mwifiex_11h_process_infra_join(struct mwifiex_private *priv, u8 **buffer,
                               struct mwifiex_bssdescriptor *bss_desc)
{
        struct mwifiex_ie_types_header *ie_header;
        struct mwifiex_ie_types_pwr_capability *cap;
        struct mwifiex_ie_types_local_pwr_constraint *constraint;
        struct ieee80211_supported_band *sband;
        u8 radio_type;
        int i;

        if (!buffer || !(*buffer))
                return;

        radio_type = mwifiex_band_to_radio_type((u8) bss_desc->bss_band);
        sband = priv->wdev.wiphy->bands[radio_type];

        cap = (struct mwifiex_ie_types_pwr_capability *)*buffer;
        cap->header.type = cpu_to_le16(WLAN_EID_PWR_CAPABILITY);
        cap->header.len = cpu_to_le16(2);
        cap->min_pwr = 0;
        cap->max_pwr = 0;
        *buffer += sizeof(*cap);

        constraint = (struct mwifiex_ie_types_local_pwr_constraint *)*buffer;
        constraint->header.type = cpu_to_le16(WLAN_EID_PWR_CONSTRAINT);
        constraint->header.len = cpu_to_le16(2);
        constraint->chan = bss_desc->channel;
        constraint->constraint = bss_desc->local_constraint;
        *buffer += sizeof(*constraint);

        ie_header = (struct mwifiex_ie_types_header *)*buffer;
        ie_header->type = cpu_to_le16(TLV_TYPE_PASSTHROUGH);
        ie_header->len  = cpu_to_le16(2 * sband->n_channels + 2);
        *buffer += sizeof(*ie_header);
        *(*buffer)++ = WLAN_EID_SUPPORTED_CHANNELS;
        *(*buffer)++ = 2 * sband->n_channels;
        for (i = 0; i < sband->n_channels; i++) {
                *(*buffer)++ = ieee80211_frequency_to_channel(
                                        sband->channels[i].center_freq);
                *(*buffer)++ = 1; /* one channel in the subband */
        }
}

/* Enable or disable the 11h extensions in the firmware */
int mwifiex_11h_activate(struct mwifiex_private *priv, bool flag)
{
        u32 enable = flag;

        /* enable master mode radar detection on AP interface */
        if ((GET_BSS_ROLE(priv) == MWIFIEX_BSS_ROLE_UAP) && enable)
                enable |= MWIFIEX_MASTER_RADAR_DET_MASK;

        return mwifiex_send_cmd(priv, HostCmd_CMD_802_11_SNMP_MIB,
                                HostCmd_ACT_GEN_SET, DOT11H_I, &enable, true);
}

/* This functions processes TLV buffer for a pending BSS Join command.
 *
 * Activate 11h functionality in the firmware if the spectrum management
 * capability bit is found in the network we are joining. Also, necessary
 * TLVs are set based on requested network's 11h capability.
 */
void mwifiex_11h_process_join(struct mwifiex_private *priv, u8 **buffer,
                              struct mwifiex_bssdescriptor *bss_desc)
{
        if (bss_desc->sensed_11h) {
                /* Activate 11h functions in firmware, turns on capability
                 * bit
                 */
                mwifiex_11h_activate(priv, true);
                priv->state_11h.is_11h_active = true;
                bss_desc->cap_info_bitmap |= WLAN_CAPABILITY_SPECTRUM_MGMT;
                mwifiex_11h_process_infra_join(priv, buffer, bss_desc);
        } else {
                /* Deactivate 11h functions in the firmware */
                mwifiex_11h_activate(priv, false);
                priv->state_11h.is_11h_active = false;
                bss_desc->cap_info_bitmap &= ~WLAN_CAPABILITY_SPECTRUM_MGMT;
        }
}

/* This is DFS CAC work queue function.
 * This delayed work emits CAC finished event for cfg80211 if
 * CAC was started earlier.
 */
void mwifiex_dfs_cac_work_queue(struct work_struct *work)
{
        struct cfg80211_chan_def chandef;
        struct delayed_work *delayed_work = to_delayed_work(work);
        struct mwifiex_private *priv =
                        container_of(delayed_work, struct mwifiex_private,
                                     dfs_cac_work);

        chandef = priv->dfs_chandef;
        if (priv->wdev.cac_started) {
                mwifiex_dbg(priv->adapter, MSG,
                            "CAC timer finished; No radar detected\n");
                cfg80211_cac_event(priv->netdev, &chandef,
                                   NL80211_RADAR_CAC_FINISHED,
                                   GFP_KERNEL);
        }
}

/* This function prepares channel report request command to FW for
 * starting radar detection.
 */
int mwifiex_cmd_issue_chan_report_request(struct mwifiex_private *priv,
                                          struct host_cmd_ds_command *cmd,
                                          void *data_buf)
{
        struct host_cmd_ds_chan_rpt_req *cr_req = &cmd->params.chan_rpt_req;
        struct mwifiex_radar_params *radar_params = (void *)data_buf;

        cmd->command = cpu_to_le16(HostCmd_CMD_CHAN_REPORT_REQUEST);
        cmd->size = cpu_to_le16(S_DS_GEN);
        le16_unaligned_add_cpu(&cmd->size,
                               sizeof(struct host_cmd_ds_chan_rpt_req));

        cr_req->chan_desc.start_freq = cpu_to_le16(MWIFIEX_A_BAND_START_FREQ);
        cr_req->chan_desc.chan_num = radar_params->chandef->chan->hw_value;
        cr_req->chan_desc.chan_width = radar_params->chandef->width;
        cr_req->msec_dwell_time = cpu_to_le32(radar_params->cac_time_ms);

        if (radar_params->cac_time_ms)
                mwifiex_dbg(priv->adapter, MSG,
                            "11h: issuing DFS Radar check for channel=%d\n",
                            radar_params->chandef->chan->hw_value);
        else
                mwifiex_dbg(priv->adapter, MSG, "cancelling CAC\n");

        return 0;
}

int mwifiex_stop_radar_detection(struct mwifiex_private *priv,
                                 struct cfg80211_chan_def *chandef)
{
        struct mwifiex_radar_params radar_params;

        memset(&radar_params, 0, sizeof(struct mwifiex_radar_params));
        radar_params.chandef = chandef;
        radar_params.cac_time_ms = 0;

        return mwifiex_send_cmd(priv, HostCmd_CMD_CHAN_REPORT_REQUEST,
                                HostCmd_ACT_GEN_SET, 0, &radar_params, true);
}

/* This function is to abort ongoing CAC upon stopping AP operations
 * or during unload.
 */
void mwifiex_abort_cac(struct mwifiex_private *priv)
{
        if (priv->wdev.cac_started) {
                if (mwifiex_stop_radar_detection(priv, &priv->dfs_chandef))
                        mwifiex_dbg(priv->adapter, ERROR,
                                    "failed to stop CAC in FW\n");
                mwifiex_dbg(priv->adapter, MSG,
                            "Aborting delayed work for CAC.\n");
                cancel_delayed_work_sync(&priv->dfs_cac_work);
                cfg80211_cac_event(priv->netdev, &priv->dfs_chandef,
                                   NL80211_RADAR_CAC_ABORTED, GFP_KERNEL);
        }
}

/* This function handles channel report event from FW during CAC period.
 * If radar is detected during CAC, driver indicates the same to cfg80211
 * and also cancels ongoing delayed work.
 */
int mwifiex_11h_handle_chanrpt_ready(struct mwifiex_private *priv,
                                     struct sk_buff *skb)
{
        struct host_cmd_ds_chan_rpt_event *rpt_event;
        struct mwifiex_ie_types_chan_rpt_data *rpt;
        u8 *evt_buf;
        u16 event_len, tlv_len;

        rpt_event = (void *)(skb->data + sizeof(u32));
        event_len = skb->len - (sizeof(struct host_cmd_ds_chan_rpt_event)+
                                sizeof(u32));

        if (le32_to_cpu(rpt_event->result) != HostCmd_RESULT_OK) {
                mwifiex_dbg(priv->adapter, ERROR,
                            "Error in channel report event\n");
                return -1;
        }

        evt_buf = (void *)&rpt_event->tlvbuf;

        while (event_len >= sizeof(struct mwifiex_ie_types_header)) {
                rpt = (void *)&rpt_event->tlvbuf;
                tlv_len = le16_to_cpu(rpt->header.len);

                switch (le16_to_cpu(rpt->header.type)) {
                case TLV_TYPE_CHANRPT_11H_BASIC:
                        if (rpt->map.radar) {
                                mwifiex_dbg(priv->adapter, MSG,
                                            "RADAR Detected on channel %d!\n",
                                            priv->dfs_chandef.chan->hw_value);
                                cancel_delayed_work_sync(&priv->dfs_cac_work);
                                cfg80211_cac_event(priv->netdev,
                                                   &priv->dfs_chandef,
                                                   NL80211_RADAR_DETECTED,
                                                   GFP_KERNEL);
                        }
                        break;
                default:
                        break;
                }

                evt_buf += (tlv_len + sizeof(rpt->header));
                event_len -= (tlv_len + sizeof(rpt->header));
        }

        return 0;
}

/* Handler for radar detected event from FW.*/
int mwifiex_11h_handle_radar_detected(struct mwifiex_private *priv,
                                      struct sk_buff *skb)
{
        struct mwifiex_radar_det_event *rdr_event;

        rdr_event = (void *)(skb->data + sizeof(u32));

        mwifiex_dbg(priv->adapter, MSG,
                    "radar detected; indicating kernel\n");
        if (mwifiex_stop_radar_detection(priv, &priv->dfs_chandef))
                mwifiex_dbg(priv->adapter, ERROR,
                            "Failed to stop CAC in FW\n");
        cfg80211_radar_event(priv->adapter->wiphy, &priv->dfs_chandef,
                             GFP_KERNEL);
        mwifiex_dbg(priv->adapter, MSG, "regdomain: %d\n",
                    rdr_event->reg_domain);
        mwifiex_dbg(priv->adapter, MSG, "radar detection type: %d\n",
                    rdr_event->det_type);

        return 0;
}

/* This is work queue function for channel switch handling.
 * This function takes care of updating new channel definitin to
 * bss config structure, restart AP and indicate channel switch success
 * to cfg80211.
 */
void mwifiex_dfs_chan_sw_work_queue(struct work_struct *work)
{
        struct mwifiex_uap_bss_param *bss_cfg;
        struct delayed_work *delayed_work = to_delayed_work(work);
        struct mwifiex_private *priv =
                        container_of(delayed_work, struct mwifiex_private,
                                     dfs_chan_sw_work);

        bss_cfg = &priv->bss_cfg;
        if (!bss_cfg->beacon_period) {
                mwifiex_dbg(priv->adapter, ERROR,
                            "channel switch: AP already stopped\n");
                return;
        }

        mwifiex_uap_set_channel(priv, bss_cfg, priv->dfs_chandef);

        if (mwifiex_config_start_uap(priv, bss_cfg)) {
                mwifiex_dbg(priv->adapter, ERROR,
                            "Failed to start AP after channel switch\n");
                return;
        }

        mwifiex_dbg(priv->adapter, MSG,
                    "indicating channel switch completion to kernel\n");
        cfg80211_ch_switch_notify(priv->netdev, &priv->dfs_chandef);
}