/******************************************************************************
 *
 * Copyright(c) 2003 - 2010 Intel Corporation. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
 *
 * The full GNU General Public License is included in this distribution in the
 * file called LICENSE.
 *
 * Contact Information:
 * Intel Linux Wireless <ilw@linux.intel.com>
 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
 *
 *****************************************************************************/

#include "iwl-dev.h"
#include "iwl-agn.h"
#include "iwl-sta.h"
#include "iwl-core.h"
#include "iwl-agn-calib.h"

static int iwlagn_disable_bss(struct iwl_priv *priv,
			      struct iwl_rxon_context *ctx,
			      struct iwl_rxon_cmd *send)
{
	__le32 old_filter = send->filter_flags;
	int ret;

	send->filter_flags &= ~RXON_FILTER_ASSOC_MSK;
	ret = iwl_send_cmd_pdu(priv, ctx->rxon_cmd, sizeof(*send), send);

	send->filter_flags = old_filter;

	if (ret)
		IWL_ERR(priv, "Error clearing ASSOC_MSK on BSS (%d)\n", ret);

	return ret;
}

static int iwlagn_disable_pan(struct iwl_priv *priv,
			      struct iwl_rxon_context *ctx,
			      struct iwl_rxon_cmd *send)
{
	__le32 old_filter = send->filter_flags;
	u8 old_dev_type = send->dev_type;
	int ret;

	send->filter_flags &= ~RXON_FILTER_ASSOC_MSK;
	send->dev_type = RXON_DEV_TYPE_P2P;
	ret = iwl_send_cmd_pdu(priv, ctx->rxon_cmd, sizeof(*send), send);

	send->filter_flags = old_filter;
	send->dev_type = old_dev_type;

	if (ret)
		IWL_ERR(priv, "Error disabling PAN (%d)\n", ret);

	/* FIXME: WAIT FOR PAN DISABLE */
	msleep(300);

	return ret;
}

static int iwlagn_update_beacon(struct iwl_priv *priv,
				struct ieee80211_vif *vif)
{
	lockdep_assert_held(&priv->mutex);

	dev_kfree_skb(priv->beacon_skb);
	priv->beacon_skb = ieee80211_beacon_get(priv->hw, vif);
	if (!priv->beacon_skb)
		return -ENOMEM;
	return iwlagn_send_beacon_cmd(priv);
}

/**
 * iwlagn_commit_rxon - commit staging_rxon to hardware
 *
 * The RXON command in staging_rxon is committed to the hardware and
 * the active_rxon structure is updated with the new data.  This
 * function correctly transitions out of the RXON_ASSOC_MSK state if
 * a HW tune is required based on the RXON structure changes.
 */
int iwlagn_commit_rxon(struct iwl_priv *priv, struct iwl_rxon_context *ctx)
{
	/* cast away the const for active_rxon in this function */
	struct iwl_rxon_cmd *active = (void *)&ctx->active;
	bool old_assoc = !!(ctx->active.filter_flags & RXON_FILTER_ASSOC_MSK);
	bool new_assoc = !!(ctx->staging.filter_flags & RXON_FILTER_ASSOC_MSK);
	int ret;

	lockdep_assert_held(&priv->mutex);

	if (!iwl_is_alive(priv))
		return -EBUSY;

	/* This function hardcodes a bunch of dual-mode assumptions */
	BUILD_BUG_ON(NUM_IWL_RXON_CTX != 2);

	if (!ctx->is_active)
		return 0;

	/* always get timestamp with Rx frame */
	ctx->staging.flags |= RXON_FLG_TSF2HOST_MSK;

	if ((ctx->vif && ctx->vif->bss_conf.use_short_slot) ||
	    !(ctx->staging.flags & RXON_FLG_BAND_24G_MSK))
		ctx->staging.flags |= RXON_FLG_SHORT_SLOT_MSK;
	else
		ctx->staging.flags &= ~RXON_FLG_SHORT_SLOT_MSK;

	ret = iwl_check_rxon_cmd(priv, ctx);
	if (ret) {
		IWL_ERR(priv, "Invalid RXON configuration. Not committing.\n");
		return -EINVAL;
	}

	/*
	 * receive commit_rxon request
	 * abort any previous channel switch if still in process
	 */
	if (priv->switch_rxon.switch_in_progress &&
	    (priv->switch_rxon.channel != ctx->staging.channel)) {
		IWL_DEBUG_11H(priv, "abort channel switch on %d\n",
		      le16_to_cpu(priv->switch_rxon.channel));
		iwl_chswitch_done(priv, false);
	}

	/*
	 * If we don't need to send a full RXON, we can use
	 * iwl_rxon_assoc_cmd which is used to reconfigure filter
	 * and other flags for the current radio configuration.
	 */
	if (!iwl_full_rxon_required(priv, ctx)) {
		ret = iwl_send_rxon_assoc(priv, ctx);
		if (ret) {
			IWL_ERR(priv, "Error setting RXON_ASSOC (%d)\n", ret);
			return ret;
		}

		memcpy(active, &ctx->staging, sizeof(*active));
		iwl_print_rx_config_cmd(priv, ctx);
		return 0;
	}

	if (priv->cfg->ops->hcmd->set_pan_params) {
		ret = priv->cfg->ops->hcmd->set_pan_params(priv);
		if (ret)
			return ret;
	}

	iwl_set_rxon_hwcrypto(priv, ctx, !priv->cfg->mod_params->sw_crypto);

	IWL_DEBUG_INFO(priv,
		       "Going to commit RXON\n"
		       "  * with%s RXON_FILTER_ASSOC_MSK\n"
		       "  * channel = %d\n"
		       "  * bssid = %pM\n",
		       (new_assoc ? "" : "out"),
		       le16_to_cpu(ctx->staging.channel),
		       ctx->staging.bssid_addr);

	/*
	 * If we are currently associated and the new config is also
	 * going to be associated, OR if the new config is simply not
	 * associated, clear associated.
	 */
	if ((old_assoc && new_assoc) || !new_assoc) {
		struct iwl_rxon_cmd *send = active;

		if (!new_assoc)
			send = &ctx->staging;

		if (ctx->ctxid == IWL_RXON_CTX_BSS)
			ret = iwlagn_disable_bss(priv, ctx, send);
		else
			ret = iwlagn_disable_pan(priv, ctx, send);
		if (ret)
			return ret;

		if (send != active)
			memcpy(active, send, sizeof(*active));

		/*
		 * Un-assoc RXON clears the station table and WEP
		 * keys, so we have to restore those afterwards.
		 */
		iwl_clear_ucode_stations(priv, ctx);
		iwl_restore_stations(priv, ctx);
		ret = iwl_restore_default_wep_keys(priv, ctx);
		if (ret) {
			IWL_ERR(priv, "Failed to restore WEP keys (%d)\n", ret);
			return ret;
		}
	}

	/* RXON timing must be before associated RXON */
	ret = iwl_send_rxon_timing(priv, ctx);
	if (ret) {
		IWL_ERR(priv, "Failed to send timing (%d)!\n", ret);
		return ret;
	}

	if (new_assoc) {
		/*
		 * We'll run into this code path when beaconing is
		 * enabled, but then we also need to send the beacon
		 * to the device.
		 */
		if (ctx->vif && (ctx->vif->type == NL80211_IFTYPE_AP)) {
			ret = iwlagn_update_beacon(priv, ctx->vif);
			if (ret) {
				IWL_ERR(priv,
					"Error sending required beacon (%d)!\n",
					ret);
				return ret;
			}
		}

		priv->start_calib = 0;
		/*
		 * Apply the new configuration.
		 *
		 * Associated RXON doesn't clear the station table in uCode,
		 * so we don't need to restore stations etc. after this.
		 */
		ret = iwl_send_cmd_pdu(priv, ctx->rxon_cmd,
			      sizeof(struct iwl_rxon_cmd), &ctx->staging);
		if (ret) {
			IWL_ERR(priv, "Error setting new RXON (%d)\n", ret);
			return ret;
		}
		memcpy(active, &ctx->staging, sizeof(*active));

		/* IBSS beacon needs to be sent after setting assoc */
		if (ctx->vif && (ctx->vif->type == NL80211_IFTYPE_ADHOC))
			if (iwlagn_update_beacon(priv, ctx->vif))
				IWL_ERR(priv, "Error sending IBSS beacon\n");
	}

	iwl_print_rx_config_cmd(priv, ctx);

	iwl_init_sensitivity(priv);

	/*
	 * If we issue a new RXON command which required a tune then we must
	 * send a new TXPOWER command or we won't be able to Tx any frames.
	 *
	 * FIXME: which RXON requires a tune? Can we optimise this out in
	 *        some cases?
	 */
	ret = iwl_set_tx_power(priv, priv->tx_power_user_lmt, true);
	if (ret) {
		IWL_ERR(priv, "Error sending TX power (%d)\n", ret);
		return ret;
	}

	return 0;
}

static void iwlagn_update_qos(struct iwl_priv *priv,
			      struct iwl_rxon_context *ctx)
{
	int ret;

	if (!ctx->is_active)
		return;

	ctx->qos_data.def_qos_parm.qos_flags = 0;

	if (ctx->qos_data.qos_active)
		ctx->qos_data.def_qos_parm.qos_flags |=
			QOS_PARAM_FLG_UPDATE_EDCA_MSK;

	if (ctx->ht.enabled)
		ctx->qos_data.def_qos_parm.qos_flags |= QOS_PARAM_FLG_TGN_MSK;

	IWL_DEBUG_QOS(priv, "send QoS cmd with Qos active=%d FLAGS=0x%X\n",
		      ctx->qos_data.qos_active,
		      ctx->qos_data.def_qos_parm.qos_flags);

	ret = iwl_send_cmd_pdu(priv, ctx->qos_cmd,
			       sizeof(struct iwl_qosparam_cmd),
			       &ctx->qos_data.def_qos_parm);
	if (ret)
		IWL_ERR(priv, "Failed to update QoS\n");
}

int iwlagn_mac_config(struct ieee80211_hw *hw, u32 changed)
{
	struct iwl_priv *priv = hw->priv;
	struct iwl_rxon_context *ctx;
	struct ieee80211_conf *conf = &hw->conf;
	struct ieee80211_channel *channel = conf->channel;
	const struct iwl_channel_info *ch_info;
	int ret = 0;
	bool ht_changed[NUM_IWL_RXON_CTX] = {};

	IWL_DEBUG_MAC80211(priv, "changed %#x", changed);

	mutex_lock(&priv->mutex);

	if (unlikely(test_bit(STATUS_SCANNING, &priv->status))) {
		IWL_DEBUG_MAC80211(priv, "leave - scanning\n");
		goto out;
	}

	if (!iwl_is_ready(priv)) {
		IWL_DEBUG_MAC80211(priv, "leave - not ready\n");
		goto out;
	}

	if (changed & (IEEE80211_CONF_CHANGE_SMPS |
		       IEEE80211_CONF_CHANGE_CHANNEL)) {
		/* mac80211 uses static for non-HT which is what we want */
		priv->current_ht_config.smps = conf->smps_mode;

		/*
		 * Recalculate chain counts.
		 *
		 * If monitor mode is enabled then mac80211 will
		 * set up the SM PS mode to OFF if an HT channel is
		 * configured.
		 */
		if (priv->cfg->ops->hcmd->set_rxon_chain)
			for_each_context(priv, ctx)
				priv->cfg->ops->hcmd->set_rxon_chain(priv, ctx);
	}

	if (changed & IEEE80211_CONF_CHANGE_CHANNEL) {
		unsigned long flags;

		ch_info = iwl_get_channel_info(priv, channel->band,
					       channel->hw_value);
		if (!is_channel_valid(ch_info)) {
			IWL_DEBUG_MAC80211(priv, "leave - invalid channel\n");
			ret = -EINVAL;
			goto out;
		}

		spin_lock_irqsave(&priv->lock, flags);

		for_each_context(priv, ctx) {
			/* Configure HT40 channels */
			if (ctx->ht.enabled != conf_is_ht(conf)) {
				ctx->ht.enabled = conf_is_ht(conf);
				ht_changed[ctx->ctxid] = true;
			}

			if (ctx->ht.enabled) {
				if (conf_is_ht40_minus(conf)) {
					ctx->ht.extension_chan_offset =
						IEEE80211_HT_PARAM_CHA_SEC_BELOW;
					ctx->ht.is_40mhz = true;
				} else if (conf_is_ht40_plus(conf)) {
					ctx->ht.extension_chan_offset =
						IEEE80211_HT_PARAM_CHA_SEC_ABOVE;
					ctx->ht.is_40mhz = true;
				} else {
					ctx->ht.extension_chan_offset =
						IEEE80211_HT_PARAM_CHA_SEC_NONE;
					ctx->ht.is_40mhz = false;
				}
			} else
				ctx->ht.is_40mhz = false;

			/*
			 * Default to no protection. Protection mode will
			 * later be set from BSS config in iwl_ht_conf
			 */
			ctx->ht.protection = IEEE80211_HT_OP_MODE_PROTECTION_NONE;

			/* if we are switching from ht to 2.4 clear flags
			 * from any ht related info since 2.4 does not
			 * support ht */
			if (le16_to_cpu(ctx->staging.channel) !=
			    channel->hw_value)
				ctx->staging.flags = 0;

			iwl_set_rxon_channel(priv, channel, ctx);
			iwl_set_rxon_ht(priv, &priv->current_ht_config);

			iwl_set_flags_for_band(priv, ctx, channel->band,
					       ctx->vif);
		}

		spin_unlock_irqrestore(&priv->lock, flags);

		iwl_update_bcast_stations(priv);

		/*
		 * The list of supported rates and rate mask can be different
		 * for each band; since the band may have changed, reset
		 * the rate mask to what mac80211 lists.
		 */
		iwl_set_rate(priv);
	}

	if (changed & (IEEE80211_CONF_CHANGE_PS |
			IEEE80211_CONF_CHANGE_IDLE)) {
		ret = iwl_power_update_mode(priv, false);
		if (ret)
			IWL_DEBUG_MAC80211(priv, "Error setting sleep level\n");
	}

	if (changed & IEEE80211_CONF_CHANGE_POWER) {
		IWL_DEBUG_MAC80211(priv, "TX Power old=%d new=%d\n",
			priv->tx_power_user_lmt, conf->power_level);

		iwl_set_tx_power(priv, conf->power_level, false);
	}

	for_each_context(priv, ctx) {
		if (!memcmp(&ctx->staging, &ctx->active, sizeof(ctx->staging)))
			continue;
		iwlagn_commit_rxon(priv, ctx);
		if (ht_changed[ctx->ctxid])
			iwlagn_update_qos(priv, ctx);
	}
 out:
	mutex_unlock(&priv->mutex);
	return ret;
}

static void iwlagn_check_needed_chains(struct iwl_priv *priv,
				       struct iwl_rxon_context *ctx,
				       struct ieee80211_bss_conf *bss_conf)
{
	struct ieee80211_vif *vif = ctx->vif;
	struct iwl_rxon_context *tmp;
	struct ieee80211_sta *sta;
	struct iwl_ht_config *ht_conf = &priv->current_ht_config;
	bool need_multiple;

	lockdep_assert_held(&priv->mutex);

	switch (vif->type) {
	case NL80211_IFTYPE_STATION:
		rcu_read_lock();
		sta = ieee80211_find_sta(vif, bss_conf->bssid);
		if (sta) {
			struct ieee80211_sta_ht_cap *ht_cap = &sta->ht_cap;
			int maxstreams;

			maxstreams = (ht_cap->mcs.tx_params &
				      IEEE80211_HT_MCS_TX_MAX_STREAMS_MASK)
					>> IEEE80211_HT_MCS_TX_MAX_STREAMS_SHIFT;
			maxstreams += 1;

			if ((ht_cap->mcs.rx_mask[1] == 0) &&
			    (ht_cap->mcs.rx_mask[2] == 0))
				need_multiple = false;
			if (maxstreams <= 1)
				need_multiple = true;
		} else {
			/*
			 * If at all, this can only happen through a race
			 * when the AP disconnects us while we're still
			 * setting up the connection, in that case mac80211
			 * will soon tell us about that.
			 */
			need_multiple = false;
		}
		rcu_read_unlock();
		break;
	case NL80211_IFTYPE_ADHOC:
		/* currently */
		need_multiple = false;
		break;
	default:
		/* only AP really */
		need_multiple = true;
		break;
	}

	ctx->ht_need_multiple_chains = need_multiple;

	if (!need_multiple) {
		/* check all contexts */
		for_each_context(priv, tmp) {
			if (!tmp->vif)
				continue;
			if (tmp->ht_need_multiple_chains) {
				need_multiple = true;
				break;
			}
		}
	}

	ht_conf->single_chain_sufficient = !need_multiple;
}

void iwlagn_bss_info_changed(struct ieee80211_hw *hw,
			     struct ieee80211_vif *vif,
			     struct ieee80211_bss_conf *bss_conf,
			     u32 changes)
{
	struct iwl_priv *priv = hw->priv;
	struct iwl_rxon_context *ctx = iwl_rxon_ctx_from_vif(vif);
	int ret;
	bool force = false;

	mutex_lock(&priv->mutex);

	if (changes & BSS_CHANGED_BEACON_INT)
		force = true;

	if (changes & BSS_CHANGED_QOS) {
		ctx->qos_data.qos_active = bss_conf->qos;
		iwlagn_update_qos(priv, ctx);
	}

	ctx->staging.assoc_id = cpu_to_le16(vif->bss_conf.aid);
	if (vif->bss_conf.use_short_preamble)
		ctx->staging.flags |= RXON_FLG_SHORT_PREAMBLE_MSK;
	else
		ctx->staging.flags &= ~RXON_FLG_SHORT_PREAMBLE_MSK;

	if (changes & BSS_CHANGED_ASSOC) {
		if (bss_conf->assoc) {
			iwl_led_associate(priv);
			priv->timestamp = bss_conf->timestamp;
			ctx->staging.filter_flags |= RXON_FILTER_ASSOC_MSK;
		} else {
			ctx->staging.filter_flags &= ~RXON_FILTER_ASSOC_MSK;
			iwl_led_disassociate(priv);
		}
	}

	if (ctx->ht.enabled) {
		ctx->ht.protection = bss_conf->ht_operation_mode &
					IEEE80211_HT_OP_MODE_PROTECTION;
		ctx->ht.non_gf_sta_present = !!(bss_conf->ht_operation_mode &
					IEEE80211_HT_OP_MODE_NON_GF_STA_PRSNT);
		iwlagn_check_needed_chains(priv, ctx, bss_conf);
	}

	if (priv->cfg->ops->hcmd->set_rxon_chain)
		priv->cfg->ops->hcmd->set_rxon_chain(priv, ctx);

	if (bss_conf->use_cts_prot && (priv->band != IEEE80211_BAND_5GHZ))
		ctx->staging.flags |= RXON_FLG_TGG_PROTECT_MSK;
	else
		ctx->staging.flags &= ~RXON_FLG_TGG_PROTECT_MSK;

	if (bss_conf->use_cts_prot)
		ctx->staging.flags |= RXON_FLG_SELF_CTS_EN;
	else
		ctx->staging.flags &= ~RXON_FLG_SELF_CTS_EN;

	memcpy(ctx->staging.bssid_addr, bss_conf->bssid, ETH_ALEN);

	if (vif->type == NL80211_IFTYPE_AP ||
	    vif->type == NL80211_IFTYPE_ADHOC) {
		if (vif->bss_conf.enable_beacon) {
			ctx->staging.filter_flags |= RXON_FILTER_ASSOC_MSK;
			priv->beacon_ctx = ctx;
		} else {
			ctx->staging.filter_flags &= ~RXON_FILTER_ASSOC_MSK;
			priv->beacon_ctx = NULL;
		}
	}

	if (force || memcmp(&ctx->staging, &ctx->active, sizeof(ctx->staging)))
		iwlagn_commit_rxon(priv, ctx);

	if (changes & BSS_CHANGED_IBSS) {
		ret = iwlagn_manage_ibss_station(priv, vif,
						 bss_conf->ibss_joined);
		if (ret)
			IWL_ERR(priv, "failed to %s IBSS station %pM\n",
				bss_conf->ibss_joined ? "add" : "remove",
				bss_conf->bssid);
	}

	if (changes & BSS_CHANGED_BEACON && vif->type == NL80211_IFTYPE_ADHOC &&
	    priv->beacon_ctx) {
		if (iwlagn_update_beacon(priv, vif))
			IWL_ERR(priv, "Error sending IBSS beacon\n");
	}

	mutex_unlock(&priv->mutex);
}

void iwlagn_post_scan(struct iwl_priv *priv)
{
	struct iwl_rxon_context *ctx;

	/*
	 * Since setting the RXON may have been deferred while
	 * performing the scan, fire one off if needed
	 */
	for_each_context(priv, ctx)
		if (memcmp(&ctx->staging, &ctx->active, sizeof(ctx->staging)))
			iwlagn_commit_rxon(priv, ctx);

	if (priv->cfg->ops->hcmd->set_pan_params)
		priv->cfg->ops->hcmd->set_pan_params(priv);
}