// SPDX-License-Identifier: GPL-2.0
/*
 * This file contains the handling of command
 * responses as well as events generated by firmware.
 */

#include <linux/hardirq.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/sched.h>
#include <linux/unaligned.h>
#include <net/cfg80211.h>

#include "cfg.h"
#include "cmd.h"

/**
 * lbs_mac_event_disconnected - handles disconnect event. It
 * reports disconnect to upper layer, clean tx/rx packets,
 * reset link state etc.
 *
 * @priv:       A pointer to struct lbs_private structure
 * @locally_generated: indicates disconnect was requested locally
 *              (usually by userspace)
 *
 * returns:     n/a
 */
void lbs_mac_event_disconnected(struct lbs_private *priv,
                                bool locally_generated)
{
        unsigned long flags;

        if (priv->connect_status != LBS_CONNECTED)
                return;

        /*
         * Cisco AP sends EAP failure and de-auth in less than 0.5 ms.
         * It causes problem in the Supplicant
         */
        msleep_interruptible(1000);

        if (priv->wdev->iftype == NL80211_IFTYPE_STATION)
                lbs_send_disconnect_notification(priv, locally_generated);

        /* report disconnect to upper layer */
        netif_stop_queue(priv->dev);
        netif_carrier_off(priv->dev);

        /* Free Tx and Rx packets */
        spin_lock_irqsave(&priv->driver_lock, flags);
        dev_kfree_skb_irq(priv->currenttxskb);
        priv->currenttxskb = NULL;
        priv->tx_pending_len = 0;
        spin_unlock_irqrestore(&priv->driver_lock, flags);

        priv->connect_status = LBS_DISCONNECTED;

        if (priv->psstate != PS_STATE_FULL_POWER) {
                /* make firmware to exit PS mode */
                lbs_deb_cmd("disconnected, so exit PS mode\n");
                lbs_set_ps_mode(priv, PS_MODE_ACTION_EXIT_PS, false);
        }
}

int lbs_process_command_response(struct lbs_private *priv, u8 *data, u32 len)
{
        uint16_t respcmd, curcmd;
        struct cmd_header *resp;
        int ret = 0;
        unsigned long flags;
        uint16_t result;

        mutex_lock(&priv->lock);
        spin_lock_irqsave(&priv->driver_lock, flags);

        if (!priv->cur_cmd) {
                lbs_deb_host("CMD_RESP: cur_cmd is NULL\n");
                ret = -1;
                spin_unlock_irqrestore(&priv->driver_lock, flags);
                goto done;
        }

        resp = (void *)data;
        curcmd = le16_to_cpu(priv->cur_cmd->cmdbuf->command);
        respcmd = le16_to_cpu(resp->command);
        result = le16_to_cpu(resp->result);

        lbs_deb_cmd("CMD_RESP: response 0x%04x, seq %d, size %d\n",
                     respcmd, le16_to_cpu(resp->seqnum), len);
        lbs_deb_hex(LBS_DEB_CMD, "CMD_RESP", (void *) resp, len);

        if (resp->seqnum != priv->cur_cmd->cmdbuf->seqnum) {
                netdev_info(priv->dev,
                            "Received CMD_RESP with invalid sequence %d (expected %d)\n",
                            le16_to_cpu(resp->seqnum),
                            le16_to_cpu(priv->cur_cmd->cmdbuf->seqnum));
                spin_unlock_irqrestore(&priv->driver_lock, flags);
                ret = -1;
                goto done;
        }
        if (respcmd != CMD_RET(curcmd) &&
            respcmd != CMD_RET_802_11_ASSOCIATE && curcmd != CMD_802_11_ASSOCIATE) {
                netdev_info(priv->dev, "Invalid CMD_RESP %x to command %x!\n",
                            respcmd, curcmd);
                spin_unlock_irqrestore(&priv->driver_lock, flags);
                ret = -1;
                goto done;
        }

        if (resp->result == cpu_to_le16(0x0004)) {
                /* 0x0004 means -EAGAIN. Drop the response, let it time out
                   and be resubmitted */
                netdev_info(priv->dev,
                            "Firmware returns DEFER to command %x. Will let it time out...\n",
                            le16_to_cpu(resp->command));
                spin_unlock_irqrestore(&priv->driver_lock, flags);
                ret = -1;
                goto done;
        }

        /* Now we got response from FW, cancel the command timer */
        timer_delete(&priv->command_timer);
        priv->cmd_timed_out = 0;

        if (respcmd == CMD_RET(CMD_802_11_PS_MODE)) {
                /* struct cmd_ds_802_11_ps_mode also contains
                 * the header
                 */
                struct cmd_ds_802_11_ps_mode *psmode = (void *)resp;
                u16 action = le16_to_cpu(psmode->action);

                lbs_deb_host(
                       "CMD_RESP: PS_MODE cmd reply result 0x%x, action 0x%x\n",
                       result, action);

                if (result) {
                        lbs_deb_host("CMD_RESP: PS command failed with 0x%x\n",
                                    result);
                        /*
                         * We should not re-try enter-ps command in
                         * ad-hoc mode. It takes place in
                         * lbs_execute_next_command().
                         */
                        if (priv->wdev->iftype == NL80211_IFTYPE_MONITOR &&
                            action == PS_MODE_ACTION_ENTER_PS)
                                priv->psmode = LBS802_11POWERMODECAM;
                } else if (action == PS_MODE_ACTION_ENTER_PS) {
                        priv->needtowakeup = 0;
                        priv->psstate = PS_STATE_AWAKE;

                        lbs_deb_host("CMD_RESP: ENTER_PS command response\n");
                        if (priv->connect_status != LBS_CONNECTED) {
                                /*
                                 * When Deauth Event received before Enter_PS command
                                 * response, We need to wake up the firmware.
                                 */
                                lbs_deb_host(
                                       "disconnected, invoking lbs_ps_wakeup\n");

                                spin_unlock_irqrestore(&priv->driver_lock, flags);
                                mutex_unlock(&priv->lock);
                                lbs_set_ps_mode(priv, PS_MODE_ACTION_EXIT_PS,
                                                false);
                                mutex_lock(&priv->lock);
                                spin_lock_irqsave(&priv->driver_lock, flags);
                        }
                } else if (action == PS_MODE_ACTION_EXIT_PS) {
                        priv->needtowakeup = 0;
                        priv->psstate = PS_STATE_FULL_POWER;
                        lbs_deb_host("CMD_RESP: EXIT_PS command response\n");
                } else {
                        lbs_deb_host("CMD_RESP: PS action 0x%X\n", action);
                }

                __lbs_complete_command(priv, priv->cur_cmd, result);
                spin_unlock_irqrestore(&priv->driver_lock, flags);

                ret = 0;
                goto done;
        }

        /* If the command is not successful, cleanup and return failure */
        if ((result != 0 || !(respcmd & 0x8000))) {
                lbs_deb_host("CMD_RESP: error 0x%04x in command reply 0x%04x\n",
                       result, respcmd);
                /*
                 * Handling errors here
                 */
                switch (respcmd) {
                case CMD_RET(CMD_GET_HW_SPEC):
                case CMD_RET(CMD_802_11_RESET):
                        lbs_deb_host("CMD_RESP: reset failed\n");
                        break;

                }
                __lbs_complete_command(priv, priv->cur_cmd, result);
                spin_unlock_irqrestore(&priv->driver_lock, flags);

                ret = -1;
                goto done;
        }

        spin_unlock_irqrestore(&priv->driver_lock, flags);

        if (priv->cur_cmd && priv->cur_cmd->callback) {
                ret = priv->cur_cmd->callback(priv, priv->cur_cmd->callback_arg,
                                resp);
        }

        spin_lock_irqsave(&priv->driver_lock, flags);

        if (priv->cur_cmd) {
                /* Clean up and Put current command back to cmdfreeq */
                __lbs_complete_command(priv, priv->cur_cmd, result);
        }
        spin_unlock_irqrestore(&priv->driver_lock, flags);

done:
        mutex_unlock(&priv->lock);
        return ret;
}

void lbs_process_event(struct lbs_private *priv, u32 event)
{
        struct cmd_header cmd;

        switch (event) {
        case MACREG_INT_CODE_LINK_SENSED:
                lbs_deb_cmd("EVENT: link sensed\n");
                break;

        case MACREG_INT_CODE_DEAUTHENTICATED:
                lbs_deb_cmd("EVENT: deauthenticated\n");
                lbs_mac_event_disconnected(priv, false);
                break;

        case MACREG_INT_CODE_DISASSOCIATED:
                lbs_deb_cmd("EVENT: disassociated\n");
                lbs_mac_event_disconnected(priv, false);
                break;

        case MACREG_INT_CODE_LINK_LOST_NO_SCAN:
                lbs_deb_cmd("EVENT: link lost\n");
                lbs_mac_event_disconnected(priv, true);
                break;

        case MACREG_INT_CODE_PS_SLEEP:
                lbs_deb_cmd("EVENT: ps sleep\n");

                /* handle unexpected PS SLEEP event */
                if (priv->psstate == PS_STATE_FULL_POWER) {
                        lbs_deb_cmd(
                               "EVENT: in FULL POWER mode, ignoring PS_SLEEP\n");
                        break;
                }
                if (!list_empty(&priv->cmdpendingq)) {
                        lbs_deb_cmd("EVENT: commands in queue, do not sleep\n");
                        break;
                }
                priv->psstate = PS_STATE_PRE_SLEEP;

                lbs_ps_confirm_sleep(priv);

                break;

        case MACREG_INT_CODE_HOST_AWAKE:
                lbs_deb_cmd("EVENT: host awake\n");
                if (priv->reset_deep_sleep_wakeup)
                        priv->reset_deep_sleep_wakeup(priv);
                priv->is_deep_sleep = 0;
                lbs_cmd_async(priv, CMD_802_11_WAKEUP_CONFIRM, &cmd,
                                sizeof(cmd));
                priv->is_host_sleep_activated = 0;
                wake_up_interruptible(&priv->host_sleep_q);
                break;

        case MACREG_INT_CODE_DEEP_SLEEP_AWAKE:
                if (priv->reset_deep_sleep_wakeup)
                        priv->reset_deep_sleep_wakeup(priv);
                lbs_deb_cmd("EVENT: ds awake\n");
                priv->is_deep_sleep = 0;
                wake_up_interruptible(&priv->ds_awake_q);
                break;

        case MACREG_INT_CODE_PS_AWAKE:
                lbs_deb_cmd("EVENT: ps awake\n");
                /* handle unexpected PS AWAKE event */
                if (priv->psstate == PS_STATE_FULL_POWER) {
                        lbs_deb_cmd(
                               "EVENT: In FULL POWER mode - ignore PS AWAKE\n");
                        break;
                }

                priv->psstate = PS_STATE_AWAKE;

                if (priv->needtowakeup) {
                        /*
                         * wait for the command processing to finish
                         * before resuming sending
                         * priv->needtowakeup will be set to FALSE
                         * in lbs_ps_wakeup()
                         */
                        lbs_deb_cmd("waking up ...\n");
                        lbs_set_ps_mode(priv, PS_MODE_ACTION_EXIT_PS, false);
                }
                break;

        case MACREG_INT_CODE_MIC_ERR_UNICAST:
                lbs_deb_cmd("EVENT: UNICAST MIC ERROR\n");
                lbs_send_mic_failureevent(priv, event);
                break;

        case MACREG_INT_CODE_MIC_ERR_MULTICAST:
                lbs_deb_cmd("EVENT: MULTICAST MIC ERROR\n");
                lbs_send_mic_failureevent(priv, event);
                break;

        case MACREG_INT_CODE_MIB_CHANGED:
                lbs_deb_cmd("EVENT: MIB CHANGED\n");
                break;
        case MACREG_INT_CODE_INIT_DONE:
                lbs_deb_cmd("EVENT: INIT DONE\n");
                break;
        case MACREG_INT_CODE_ADHOC_BCN_LOST:
                lbs_deb_cmd("EVENT: ADHOC beacon lost\n");
                break;
        case MACREG_INT_CODE_RSSI_LOW:
                netdev_alert(priv->dev, "EVENT: rssi low\n");
                break;
        case MACREG_INT_CODE_SNR_LOW:
                netdev_alert(priv->dev, "EVENT: snr low\n");
                break;
        case MACREG_INT_CODE_MAX_FAIL:
                netdev_alert(priv->dev, "EVENT: max fail\n");
                break;
        case MACREG_INT_CODE_RSSI_HIGH:
                netdev_alert(priv->dev, "EVENT: rssi high\n");
                break;
        case MACREG_INT_CODE_SNR_HIGH:
                netdev_alert(priv->dev, "EVENT: snr high\n");
                break;

        case MACREG_INT_CODE_MESH_AUTO_STARTED:
                /* Ignore spurious autostart events */
                netdev_info(priv->dev, "EVENT: MESH_AUTO_STARTED (ignoring)\n");
                break;

        default:
                netdev_alert(priv->dev, "EVENT: unknown event id %d\n", event);
                break;
        }
}