iwl-core.c

/******************************************************************************
 *
 * GPL LICENSE SUMMARY
 *
 * Copyright(c) 2008 - 2011 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.GPL.
 *
 * Contact Information:
 *  Intel Linux Wireless <ilw@linux.intel.com>
 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
 *****************************************************************************/

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/etherdevice.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <net/mac80211.h>

#include "iwl-eeprom.h"
#include "iwl-dev.h" /* FIXME: remove */
#include "iwl-debug.h"
#include "iwl-core.h"
#include "iwl-io.h"
#include "iwl-power.h"
#include "iwl-sta.h"
#include "iwl-helpers.h"


/*
 * set bt_coex_active to true, uCode will do kill/defer
 * every time the priority line is asserted (BT is sending signals on the
 * priority line in the PCIx).
 * set bt_coex_active to false, uCode will ignore the BT activity and
 * perform the normal operation
 *
 * User might experience transmit issue on some platform due to WiFi/BT
 * co-exist problem. The possible behaviors are:
 *   Able to scan and finding all the available AP
 *   Not able to associate with any AP
 * On those platforms, WiFi communication can be restored by set
 * "bt_coex_active" module parameter to "false"
 *
 * default: bt_coex_active = true (BT_COEX_ENABLE)
 */
bool bt_coex_active = true;
module_param(bt_coex_active, bool, S_IRUGO);
MODULE_PARM_DESC(bt_coex_active, "enable wifi/bluetooth co-exist");

u32 iwl_debug_level;

const u8 iwl_bcast_addr[ETH_ALEN] = { 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };


/* This function both allocates and initializes hw and priv. */
struct ieee80211_hw *iwl_alloc_all(struct iwl_cfg *cfg)
{
	struct iwl_priv *priv;
	/* mac80211 allocates memory for this device instance, including
	 *   space for this driver's private structure */
	struct ieee80211_hw *hw;

	hw = ieee80211_alloc_hw(sizeof(struct iwl_priv),
				cfg->ops->ieee80211_ops);
	if (hw == NULL) {
		pr_err("%s: Can not allocate network device\n",
		       cfg->name);
		goto out;
	}

	priv = hw->priv;
	priv->hw = hw;

out:
	return hw;
}

#define MAX_BIT_RATE_40_MHZ 150 /* Mbps */
#define MAX_BIT_RATE_20_MHZ 72 /* Mbps */
static void iwlcore_init_ht_hw_capab(const struct iwl_priv *priv,
			      struct ieee80211_sta_ht_cap *ht_info,
			      enum ieee80211_band band)
{
	u16 max_bit_rate = 0;
	u8 rx_chains_num = priv->hw_params.rx_chains_num;
	u8 tx_chains_num = priv->hw_params.tx_chains_num;

	ht_info->cap = 0;
	memset(&ht_info->mcs, 0, sizeof(ht_info->mcs));

	ht_info->ht_supported = true;

	if (priv->cfg->ht_params &&
	    priv->cfg->ht_params->ht_greenfield_support)
		ht_info->cap |= IEEE80211_HT_CAP_GRN_FLD;
	ht_info->cap |= IEEE80211_HT_CAP_SGI_20;
	max_bit_rate = MAX_BIT_RATE_20_MHZ;
	if (priv->hw_params.ht40_channel & BIT(band)) {
		ht_info->cap |= IEEE80211_HT_CAP_SUP_WIDTH_20_40;
		ht_info->cap |= IEEE80211_HT_CAP_SGI_40;
		ht_info->mcs.rx_mask[4] = 0x01;
		max_bit_rate = MAX_BIT_RATE_40_MHZ;
	}

	if (priv->cfg->mod_params->amsdu_size_8K)
		ht_info->cap |= IEEE80211_HT_CAP_MAX_AMSDU;

	ht_info->ampdu_factor = CFG_HT_RX_AMPDU_FACTOR_DEF;
	if (priv->cfg->bt_params && priv->cfg->bt_params->ampdu_factor)
		ht_info->ampdu_factor = priv->cfg->bt_params->ampdu_factor;
	ht_info->ampdu_density = CFG_HT_MPDU_DENSITY_DEF;
	if (priv->cfg->bt_params && priv->cfg->bt_params->ampdu_density)
		ht_info->ampdu_density = priv->cfg->bt_params->ampdu_density;

	ht_info->mcs.rx_mask[0] = 0xFF;
	if (rx_chains_num >= 2)
		ht_info->mcs.rx_mask[1] = 0xFF;
	if (rx_chains_num >= 3)
		ht_info->mcs.rx_mask[2] = 0xFF;

	/* Highest supported Rx data rate */
	max_bit_rate *= rx_chains_num;
	WARN_ON(max_bit_rate & ~IEEE80211_HT_MCS_RX_HIGHEST_MASK);
	ht_info->mcs.rx_highest = cpu_to_le16(max_bit_rate);

	/* Tx MCS capabilities */
	ht_info->mcs.tx_params = IEEE80211_HT_MCS_TX_DEFINED;
	if (tx_chains_num != rx_chains_num) {
		ht_info->mcs.tx_params |= IEEE80211_HT_MCS_TX_RX_DIFF;
		ht_info->mcs.tx_params |= ((tx_chains_num - 1) <<
				IEEE80211_HT_MCS_TX_MAX_STREAMS_SHIFT);
	}
}

/**
 * iwlcore_init_geos - Initialize mac80211's geo/channel info based from eeprom
 */
int iwlcore_init_geos(struct iwl_priv *priv)
{
	struct iwl_channel_info *ch;
	struct ieee80211_supported_band *sband;
	struct ieee80211_channel *channels;
	struct ieee80211_channel *geo_ch;
	struct ieee80211_rate *rates;
	int i = 0;

	if (priv->bands[IEEE80211_BAND_2GHZ].n_bitrates ||
	    priv->bands[IEEE80211_BAND_5GHZ].n_bitrates) {
		IWL_DEBUG_INFO(priv, "Geography modes already initialized.\n");
		set_bit(STATUS_GEO_CONFIGURED, &priv->status);
		return 0;
	}

	channels = kzalloc(sizeof(struct ieee80211_channel) *
			   priv->channel_count, GFP_KERNEL);
	if (!channels)
		return -ENOMEM;

	rates = kzalloc((sizeof(struct ieee80211_rate) * IWL_RATE_COUNT_LEGACY),
			GFP_KERNEL);
	if (!rates) {
		kfree(channels);
		return -ENOMEM;
	}

	/* 5.2GHz channels start after the 2.4GHz channels */
	sband = &priv->bands[IEEE80211_BAND_5GHZ];
	sband->channels = &channels[ARRAY_SIZE(iwl_eeprom_band_1)];
	/* just OFDM */
	sband->bitrates = &rates[IWL_FIRST_OFDM_RATE];
	sband->n_bitrates = IWL_RATE_COUNT_LEGACY - IWL_FIRST_OFDM_RATE;

	if (priv->cfg->sku & IWL_SKU_N)
		iwlcore_init_ht_hw_capab(priv, &sband->ht_cap,
					 IEEE80211_BAND_5GHZ);

	sband = &priv->bands[IEEE80211_BAND_2GHZ];
	sband->channels = channels;
	/* OFDM & CCK */
	sband->bitrates = rates;
	sband->n_bitrates = IWL_RATE_COUNT_LEGACY;

	if (priv->cfg->sku & IWL_SKU_N)
		iwlcore_init_ht_hw_capab(priv, &sband->ht_cap,
					 IEEE80211_BAND_2GHZ);

	priv->ieee_channels = channels;
	priv->ieee_rates = rates;

	for (i = 0;  i < priv->channel_count; i++) {
		ch = &priv->channel_info[i];

		/* FIXME: might be removed if scan is OK */
		if (!is_channel_valid(ch))
			continue;

		sband =  &priv->bands[ch->band];

		geo_ch = &sband->channels[sband->n_channels++];

		geo_ch->center_freq =
			ieee80211_channel_to_frequency(ch->channel, ch->band);
		geo_ch->max_power = ch->max_power_avg;
		geo_ch->max_antenna_gain = 0xff;
		geo_ch->hw_value = ch->channel;

		if (is_channel_valid(ch)) {
			if (!(ch->flags & EEPROM_CHANNEL_IBSS))
				geo_ch->flags |= IEEE80211_CHAN_NO_IBSS;

			if (!(ch->flags & EEPROM_CHANNEL_ACTIVE))
				geo_ch->flags |= IEEE80211_CHAN_PASSIVE_SCAN;

			if (ch->flags & EEPROM_CHANNEL_RADAR)
				geo_ch->flags |= IEEE80211_CHAN_RADAR;

			geo_ch->flags |= ch->ht40_extension_channel;

			if (ch->max_power_avg > priv->tx_power_device_lmt)
				priv->tx_power_device_lmt = ch->max_power_avg;
		} else {
			geo_ch->flags |= IEEE80211_CHAN_DISABLED;
		}

		IWL_DEBUG_INFO(priv, "Channel %d Freq=%d[%sGHz] %s flag=0x%X\n",
				ch->channel, geo_ch->center_freq,
				is_channel_a_band(ch) ?  "5.2" : "2.4",
				geo_ch->flags & IEEE80211_CHAN_DISABLED ?
				"restricted" : "valid",
				 geo_ch->flags);
	}

	if ((priv->bands[IEEE80211_BAND_5GHZ].n_channels == 0) &&
	     priv->cfg->sku & IWL_SKU_A) {
		IWL_INFO(priv, "Incorrectly detected BG card as ABG. "
			"Please send your PCI ID 0x%04X:0x%04X to maintainer.\n",
			   priv->pci_dev->device,
			   priv->pci_dev->subsystem_device);
		priv->cfg->sku &= ~IWL_SKU_A;
	}

	IWL_INFO(priv, "Tunable channels: %d 802.11bg, %d 802.11a channels\n",
		   priv->bands[IEEE80211_BAND_2GHZ].n_channels,
		   priv->bands[IEEE80211_BAND_5GHZ].n_channels);

	set_bit(STATUS_GEO_CONFIGURED, &priv->status);

	return 0;
}

/*
 * iwlcore_free_geos - undo allocations in iwlcore_init_geos
 */
void iwlcore_free_geos(struct iwl_priv *priv)
{
	kfree(priv->ieee_channels);
	kfree(priv->ieee_rates);
	clear_bit(STATUS_GEO_CONFIGURED, &priv->status);
}

static bool iwl_is_channel_extension(struct iwl_priv *priv,
				     enum ieee80211_band band,
				     u16 channel, u8 extension_chan_offset)
{
	const struct iwl_channel_info *ch_info;

	ch_info = iwl_get_channel_info(priv, band, channel);
	if (!is_channel_valid(ch_info))
		return false;

	if (extension_chan_offset == IEEE80211_HT_PARAM_CHA_SEC_ABOVE)
		return !(ch_info->ht40_extension_channel &
					IEEE80211_CHAN_NO_HT40PLUS);
	else if (extension_chan_offset == IEEE80211_HT_PARAM_CHA_SEC_BELOW)
		return !(ch_info->ht40_extension_channel &
					IEEE80211_CHAN_NO_HT40MINUS);

	return false;
}

bool iwl_is_ht40_tx_allowed(struct iwl_priv *priv,
			    struct iwl_rxon_context *ctx,
			    struct ieee80211_sta_ht_cap *ht_cap)
{
	if (!ctx->ht.enabled || !ctx->ht.is_40mhz)
		return false;

	/*
	 * We do not check for IEEE80211_HT_CAP_SUP_WIDTH_20_40
	 * the bit will not set if it is pure 40MHz case
	 */
	if (ht_cap && !ht_cap->ht_supported)
		return false;

#ifdef CONFIG_IWLWIFI_DEBUGFS
	if (priv->disable_ht40)
		return false;
#endif

	return iwl_is_channel_extension(priv, priv->band,
			le16_to_cpu(ctx->staging.channel),
			ctx->ht.extension_chan_offset);
}

static u16 iwl_adjust_beacon_interval(u16 beacon_val, u16 max_beacon_val)
{
	u16 new_val;
	u16 beacon_factor;

	/*
	 * If mac80211 hasn't given us a beacon interval, program
	 * the default into the device (not checking this here
	 * would cause the adjustment below to return the maximum
	 * value, which may break PAN.)
	 */
	if (!beacon_val)
		return DEFAULT_BEACON_INTERVAL;

	/*
	 * If the beacon interval we obtained from the peer
	 * is too large, we'll have to wake up more often
	 * (and in IBSS case, we'll beacon too much)
	 *
	 * For example, if max_beacon_val is 4096, and the
	 * requested beacon interval is 7000, we'll have to
	 * use 3500 to be able to wake up on the beacons.
	 *
	 * This could badly influence beacon detection stats.
	 */

	beacon_factor = (beacon_val + max_beacon_val) / max_beacon_val;
	new_val = beacon_val / beacon_factor;

	if (!new_val)
		new_val = max_beacon_val;

	return new_val;
}

int iwl_send_rxon_timing(struct iwl_priv *priv, struct iwl_rxon_context *ctx)
{
	u64 tsf;
	s32 interval_tm, rem;
	struct ieee80211_conf *conf = NULL;
	u16 beacon_int;
	struct ieee80211_vif *vif = ctx->vif;

	conf = ieee80211_get_hw_conf(priv->hw);

	lockdep_assert_held(&priv->mutex);

	memset(&ctx->timing, 0, sizeof(struct iwl_rxon_time_cmd));

	ctx->timing.timestamp = cpu_to_le64(priv->timestamp);
	ctx->timing.listen_interval = cpu_to_le16(conf->listen_interval);

	beacon_int = vif ? vif->bss_conf.beacon_int : 0;

	/*
	 * TODO: For IBSS we need to get atim_window from mac80211,
	 *	 for now just always use 0
	 */
	ctx->timing.atim_window = 0;

	if (ctx->ctxid == IWL_RXON_CTX_PAN &&
	    (!ctx->vif || ctx->vif->type != NL80211_IFTYPE_STATION) &&
	    iwl_is_associated(priv, IWL_RXON_CTX_BSS) &&
	    priv->contexts[IWL_RXON_CTX_BSS].vif &&
	    priv->contexts[IWL_RXON_CTX_BSS].vif->bss_conf.beacon_int) {
		ctx->timing.beacon_interval =
			priv->contexts[IWL_RXON_CTX_BSS].timing.beacon_interval;
		beacon_int = le16_to_cpu(ctx->timing.beacon_interval);
	} else if (ctx->ctxid == IWL_RXON_CTX_BSS &&
		   iwl_is_associated(priv, IWL_RXON_CTX_PAN) &&
		   priv->contexts[IWL_RXON_CTX_PAN].vif &&
		   priv->contexts[IWL_RXON_CTX_PAN].vif->bss_conf.beacon_int &&
		   (!iwl_is_associated_ctx(ctx) || !ctx->vif ||
		    !ctx->vif->bss_conf.beacon_int)) {
		ctx->timing.beacon_interval =
			priv->contexts[IWL_RXON_CTX_PAN].timing.beacon_interval;
		beacon_int = le16_to_cpu(ctx->timing.beacon_interval);
	} else {
		beacon_int = iwl_adjust_beacon_interval(beacon_int,
				priv->hw_params.max_beacon_itrvl * TIME_UNIT);
		ctx->timing.beacon_interval = cpu_to_le16(beacon_int);
	}

	tsf = priv->timestamp; /* tsf is modifed by do_div: copy it */
	interval_tm = beacon_int * TIME_UNIT;
	rem = do_div(tsf, interval_tm);
	ctx->timing.beacon_init_val = cpu_to_le32(interval_tm - rem);

	ctx->timing.dtim_period = vif ? (vif->bss_conf.dtim_period ?: 1) : 1;

	IWL_DEBUG_ASSOC(priv,
			"beacon interval %d beacon timer %d beacon tim %d\n",
			le16_to_cpu(ctx->timing.beacon_interval),
			le32_to_cpu(ctx->timing.beacon_init_val),
			le16_to_cpu(ctx->timing.atim_window));

	return iwl_send_cmd_pdu(priv, ctx->rxon_timing_cmd,
				sizeof(ctx->timing), &ctx->timing);
}

void iwl_set_rxon_hwcrypto(struct iwl_priv *priv, struct iwl_rxon_context *ctx,
			   int hw_decrypt)
{
	struct iwl_rxon_cmd *rxon = &ctx->staging;

	if (hw_decrypt)
		rxon->filter_flags &= ~RXON_FILTER_DIS_DECRYPT_MSK;
	else
		rxon->filter_flags |= RXON_FILTER_DIS_DECRYPT_MSK;

}

/* validate RXON structure is valid */
int iwl_check_rxon_cmd(struct iwl_priv *priv, struct iwl_rxon_context *ctx)
{
	struct iwl_rxon_cmd *rxon = &ctx->staging;
	bool error = false;

	if (rxon->flags & RXON_FLG_BAND_24G_MSK) {
		if (rxon->flags & RXON_FLG_TGJ_NARROW_BAND_MSK) {
			IWL_WARN(priv, "check 2.4G: wrong narrow\n");
			error = true;
		}
		if (rxon->flags & RXON_FLG_RADAR_DETECT_MSK) {
			IWL_WARN(priv, "check 2.4G: wrong radar\n");
			error = true;
		}
	} else {
		if (!(rxon->flags & RXON_FLG_SHORT_SLOT_MSK)) {
			IWL_WARN(priv, "check 5.2G: not short slot!\n");
			error = true;
		}
		if (rxon->flags & RXON_FLG_CCK_MSK) {
			IWL_WARN(priv, "check 5.2G: CCK!\n");
			error = true;
		}
	}
	if ((rxon->node_addr[0] | rxon->bssid_addr[0]) & 0x1) {
		IWL_WARN(priv, "mac/bssid mcast!\n");
		error = true;
	}

	/* make sure basic rates 6Mbps and 1Mbps are supported */
	if ((rxon->ofdm_basic_rates & IWL_RATE_6M_MASK) == 0 &&
	    (rxon->cck_basic_rates & IWL_RATE_1M_MASK) == 0) {
		IWL_WARN(priv, "neither 1 nor 6 are basic\n");
		error = true;
	}

	if (le16_to_cpu(rxon->assoc_id) > 2007) {
		IWL_WARN(priv, "aid > 2007\n");
		error = true;
	}

	if ((rxon->flags & (RXON_FLG_CCK_MSK | RXON_FLG_SHORT_SLOT_MSK))
			== (RXON_FLG_CCK_MSK | RXON_FLG_SHORT_SLOT_MSK)) {
		IWL_WARN(priv, "CCK and short slot\n");
		error = true;
	}

	if ((rxon->flags & (RXON_FLG_CCK_MSK | RXON_FLG_AUTO_DETECT_MSK))
			== (RXON_FLG_CCK_MSK | RXON_FLG_AUTO_DETECT_MSK)) {
		IWL_WARN(priv, "CCK and auto detect");
		error = true;
	}

	if ((rxon->flags & (RXON_FLG_AUTO_DETECT_MSK |
			    RXON_FLG_TGG_PROTECT_MSK)) ==
			    RXON_FLG_TGG_PROTECT_MSK) {
		IWL_WARN(priv, "TGg but no auto-detect\n");
		error = true;
	}

	if (error)
		IWL_WARN(priv, "Tuning to channel %d\n",
			    le16_to_cpu(rxon->channel));

	if (error) {
		IWL_ERR(priv, "Invalid RXON\n");
		return -EINVAL;
	}
	return 0;
}

/**
 * iwl_full_rxon_required - check if full RXON (vs RXON_ASSOC) cmd is needed
 * @priv: staging_rxon is compared to active_rxon
 *
 * If the RXON structure is changing enough to require a new tune,
 * or is clearing the RXON_FILTER_ASSOC_MSK, then return 1 to indicate that
 * a new tune (full RXON command, rather than RXON_ASSOC cmd) is required.
 */
int iwl_full_rxon_required(struct iwl_priv *priv,
			   struct iwl_rxon_context *ctx)
{
	const struct iwl_rxon_cmd *staging = &ctx->staging;
	const struct iwl_rxon_cmd *active = &ctx->active;

#define CHK(cond)							\
	if ((cond)) {							\
		IWL_DEBUG_INFO(priv, "need full RXON - " #cond "\n");	\
		return 1;						\
	}

#define CHK_NEQ(c1, c2)						\
	if ((c1) != (c2)) {					\
		IWL_DEBUG_INFO(priv, "need full RXON - "	\
			       #c1 " != " #c2 " - %d != %d\n",	\
			       (c1), (c2));			\
		return 1;					\
	}

	/* These items are only settable from the full RXON command */
	CHK(!iwl_is_associated_ctx(ctx));
	CHK(compare_ether_addr(staging->bssid_addr, active->bssid_addr));
	CHK(compare_ether_addr(staging->node_addr, active->node_addr));
	CHK(compare_ether_addr(staging->wlap_bssid_addr,
				active->wlap_bssid_addr));
	CHK_NEQ(staging->dev_type, active->dev_type);
	CHK_NEQ(staging->channel, active->channel);
	CHK_NEQ(staging->air_propagation, active->air_propagation);
	CHK_NEQ(staging->ofdm_ht_single_stream_basic_rates,
		active->ofdm_ht_single_stream_basic_rates);
	CHK_NEQ(staging->ofdm_ht_dual_stream_basic_rates,
		active->ofdm_ht_dual_stream_basic_rates);
	CHK_NEQ(staging->ofdm_ht_triple_stream_basic_rates,
		active->ofdm_ht_triple_stream_basic_rates);
	CHK_NEQ(staging->assoc_id, active->assoc_id);

	/* flags, filter_flags, ofdm_basic_rates, and cck_basic_rates can
	 * be updated with the RXON_ASSOC command -- however only some
	 * flag transitions are allowed using RXON_ASSOC */

	/* Check if we are not switching bands */
	CHK_NEQ(staging->flags & RXON_FLG_BAND_24G_MSK,
		active->flags & RXON_FLG_BAND_24G_MSK);

	/* Check if we are switching association toggle */
	CHK_NEQ(staging->filter_flags & RXON_FILTER_ASSOC_MSK,
		active->filter_flags & RXON_FILTER_ASSOC_MSK);

#undef CHK
#undef CHK_NEQ

	return 0;
}

u8 iwl_rate_get_lowest_plcp(struct iwl_priv *priv,
			    struct iwl_rxon_context *ctx)
{
	/*
	 * Assign the lowest rate -- should really get this from
	 * the beacon skb from mac80211.
	 */
	if (ctx->staging.flags & RXON_FLG_BAND_24G_MSK)
		return IWL_RATE_1M_PLCP;
	else
		return IWL_RATE_6M_PLCP;
}

static void _iwl_set_rxon_ht(struct iwl_priv *priv,
			     struct iwl_ht_config *ht_conf,
			     struct iwl_rxon_context *ctx)
{
	struct iwl_rxon_cmd *rxon = &ctx->staging;

	if (!ctx->ht.enabled) {
		rxon->flags &= ~(RXON_FLG_CHANNEL_MODE_MSK |
			RXON_FLG_CTRL_CHANNEL_LOC_HI_MSK |
			RXON_FLG_HT40_PROT_MSK |
			RXON_FLG_HT_PROT_MSK);
		return;
	}

	/* FIXME: if the definition of ht.protection changed, the "translation"
	 * will be needed for rxon->flags
	 */
	rxon->flags |= cpu_to_le32(ctx->ht.protection << RXON_FLG_HT_OPERATING_MODE_POS);

	/* Set up channel bandwidth:
	 * 20 MHz only, 20/40 mixed or pure 40 if ht40 ok */
	/* clear the HT channel mode before set the mode */
	rxon->flags &= ~(RXON_FLG_CHANNEL_MODE_MSK |
			 RXON_FLG_CTRL_CHANNEL_LOC_HI_MSK);
	if (iwl_is_ht40_tx_allowed(priv, ctx, NULL)) {
		/* pure ht40 */
		if (ctx->ht.protection == IEEE80211_HT_OP_MODE_PROTECTION_20MHZ) {
			rxon->flags |= RXON_FLG_CHANNEL_MODE_PURE_40;
			/* Note: control channel is opposite of extension channel */
			switch (ctx->ht.extension_chan_offset) {
			case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
				rxon->flags &= ~RXON_FLG_CTRL_CHANNEL_LOC_HI_MSK;
				break;
			case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
				rxon->flags |= RXON_FLG_CTRL_CHANNEL_LOC_HI_MSK;
				break;
			}
		} else {
			/* Note: control channel is opposite of extension channel */
			switch (ctx->ht.extension_chan_offset) {
			case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
				rxon->flags &= ~(RXON_FLG_CTRL_CHANNEL_LOC_HI_MSK);
				rxon->flags |= RXON_FLG_CHANNEL_MODE_MIXED;
				break;
			case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
				rxon->flags |= RXON_FLG_CTRL_CHANNEL_LOC_HI_MSK;
				rxon->flags |= RXON_FLG_CHANNEL_MODE_MIXED;
				break;
			case IEEE80211_HT_PARAM_CHA_SEC_NONE:
			default:
				/* channel location only valid if in Mixed mode */
				IWL_ERR(priv, "invalid extension channel offset\n");
				break;
			}
		}
	} else {
		rxon->flags |= RXON_FLG_CHANNEL_MODE_LEGACY;
	}

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

	IWL_DEBUG_ASSOC(priv, "rxon flags 0x%X operation mode :0x%X "
			"extension channel offset 0x%x\n",
			le32_to_cpu(rxon->flags), ctx->ht.protection,
			ctx->ht.extension_chan_offset);
}

void iwl_set_rxon_ht(struct iwl_priv *priv, struct iwl_ht_config *ht_conf)
{
	struct iwl_rxon_context *ctx;

	for_each_context(priv, ctx)
		_iwl_set_rxon_ht(priv, ht_conf, ctx);
}

/* Return valid, unused, channel for a passive scan to reset the RF */
u8 iwl_get_single_channel_number(struct iwl_priv *priv,
				 enum ieee80211_band band)
{
	const struct iwl_channel_info *ch_info;
	int i;
	u8 channel = 0;
	u8 min, max;
	struct iwl_rxon_context *ctx;

	if (band == IEEE80211_BAND_5GHZ) {
		min = 14;
		max = priv->channel_count;
	} else {
		min = 0;
		max = 14;
	}

	for (i = min; i < max; i++) {
		bool busy = false;

		for_each_context(priv, ctx) {
			busy = priv->channel_info[i].channel ==
				le16_to_cpu(ctx->staging.channel);
			if (busy)
				break;
		}

		if (busy)
			continue;

		channel = priv->channel_info[i].channel;
		ch_info = iwl_get_channel_info(priv, band, channel);
		if (is_channel_valid(ch_info))
			break;
	}

	return channel;
}

/**
 * iwl_set_rxon_channel - Set the band and channel values in staging RXON
 * @ch: requested channel as a pointer to struct ieee80211_channel

 * NOTE:  Does not commit to the hardware; it sets appropriate bit fields
 * in the staging RXON flag structure based on the ch->band
 */
int iwl_set_rxon_channel(struct iwl_priv *priv, struct ieee80211_channel *ch,
			 struct iwl_rxon_context *ctx)
{
	enum ieee80211_band band = ch->band;
	u16 channel = ch->hw_value;

	if ((le16_to_cpu(ctx->staging.channel) == channel) &&
	    (priv->band == band))
		return 0;

	ctx->staging.channel = cpu_to_le16(channel);
	if (band == IEEE80211_BAND_5GHZ)
		ctx->staging.flags &= ~RXON_FLG_BAND_24G_MSK;
	else
		ctx->staging.flags |= RXON_FLG_BAND_24G_MSK;

	priv->band = band;

	IWL_DEBUG_INFO(priv, "Staging channel set to %d [%d]\n", channel, band);

	return 0;
}

void iwl_set_flags_for_band(struct iwl_priv *priv,
			    struct iwl_rxon_context *ctx,
			    enum ieee80211_band band,
			    struct ieee80211_vif *vif)
{
	if (band == IEEE80211_BAND_5GHZ) {
		ctx->staging.flags &=
		    ~(RXON_FLG_BAND_24G_MSK | RXON_FLG_AUTO_DETECT_MSK
		      | RXON_FLG_CCK_MSK);
		ctx->staging.flags |= RXON_FLG_SHORT_SLOT_MSK;
	} else {
		/* Copied from iwl_post_associate() */
		if (vif && vif->bss_conf.use_short_slot)
			ctx->staging.flags |= RXON_FLG_SHORT_SLOT_MSK;
		else
			ctx->staging.flags &= ~RXON_FLG_SHORT_SLOT_MSK;

		ctx->staging.flags |= RXON_FLG_BAND_24G_MSK;
		ctx->staging.flags |= RXON_FLG_AUTO_DETECT_MSK;
		ctx->staging.flags &= ~RXON_FLG_CCK_MSK;
	}
}

/*
 * initialize rxon structure with default values from eeprom
 */
void iwl_connection_init_rx_config(struct iwl_priv *priv,
				   struct iwl_rxon_context *ctx)
{
	const struct iwl_channel_info *ch_info;

	memset(&ctx->staging, 0, sizeof(ctx->staging));

	if (!ctx->vif) {
		ctx->staging.dev_type = ctx->unused_devtype;
	} else switch (ctx->vif->type) {
	case NL80211_IFTYPE_AP:
		ctx->staging.dev_type = ctx->ap_devtype;
		break;

	case NL80211_IFTYPE_STATION:
		ctx->staging.dev_type = ctx->station_devtype;
		ctx->staging.filter_flags = RXON_FILTER_ACCEPT_GRP_MSK;
		break;

	case NL80211_IFTYPE_ADHOC:
		ctx->staging.dev_type = ctx->ibss_devtype;
		ctx->staging.flags = RXON_FLG_SHORT_PREAMBLE_MSK;
		ctx->staging.filter_flags = RXON_FILTER_BCON_AWARE_MSK |
						  RXON_FILTER_ACCEPT_GRP_MSK;
		break;

	default:
		IWL_ERR(priv, "Unsupported interface type %d\n",
			ctx->vif->type);
		break;
	}

#if 0
	/* TODO:  Figure out when short_preamble would be set and cache from
	 * that */
	if (!hw_to_local(priv->hw)->short_preamble)
		ctx->staging.flags &= ~RXON_FLG_SHORT_PREAMBLE_MSK;
	else
		ctx->staging.flags |= RXON_FLG_SHORT_PREAMBLE_MSK;
#endif

	ch_info = iwl_get_channel_info(priv, priv->band,
				       le16_to_cpu(ctx->active.channel));

	if (!ch_info)
		ch_info = &priv->channel_info[0];

	ctx->staging.channel = cpu_to_le16(ch_info->channel);
	priv->band = ch_info->band;

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

	ctx->staging.ofdm_basic_rates =
	    (IWL_OFDM_RATES_MASK >> IWL_FIRST_OFDM_RATE) & 0xFF;
	ctx->staging.cck_basic_rates =
	    (IWL_CCK_RATES_MASK >> IWL_FIRST_CCK_RATE) & 0xF;

	/* clear both MIX and PURE40 mode flag */
	ctx->staging.flags &= ~(RXON_FLG_CHANNEL_MODE_MIXED |
					RXON_FLG_CHANNEL_MODE_PURE_40);
	if (ctx->vif)
		memcpy(ctx->staging.node_addr, ctx->vif->addr, ETH_ALEN);

	ctx->staging.ofdm_ht_single_stream_basic_rates = 0xff;
	ctx->staging.ofdm_ht_dual_stream_basic_rates = 0xff;
	ctx->staging.ofdm_ht_triple_stream_basic_rates = 0xff;
}

void iwl_set_rate(struct iwl_priv *priv)
{
	const struct ieee80211_supported_band *hw = NULL;
	struct ieee80211_rate *rate;
	struct iwl_rxon_context *ctx;
	int i;

	hw = iwl_get_hw_mode(priv, priv->band);
	if (!hw) {
		IWL_ERR(priv, "Failed to set rate: unable to get hw mode\n");
		return;
	}

	priv->active_rate = 0;

	for (i = 0; i < hw->n_bitrates; i++) {
		rate = &(hw->bitrates[i]);
		if (rate->hw_value < IWL_RATE_COUNT_LEGACY)
			priv->active_rate |= (1 << rate->hw_value);
	}

	IWL_DEBUG_RATE(priv, "Set active_rate = %0x\n", priv->active_rate);

	for_each_context(priv, ctx) {
		ctx->staging.cck_basic_rates =
		    (IWL_CCK_BASIC_RATES_MASK >> IWL_FIRST_CCK_RATE) & 0xF;

		ctx->staging.ofdm_basic_rates =
		   (IWL_OFDM_BASIC_RATES_MASK >> IWL_FIRST_OFDM_RATE) & 0xFF;
	}
}

void iwl_chswitch_done(struct iwl_priv *priv, bool is_success)
{
	/*
	 * MULTI-FIXME
	 * See iwl_mac_channel_switch.
	 */
	struct iwl_rxon_context *ctx = &priv->contexts[IWL_RXON_CTX_BSS];

	if (test_bit(STATUS_EXIT_PENDING, &priv->status))
		return;

	if (priv->switch_rxon.switch_in_progress) {
		ieee80211_chswitch_done(ctx->vif, is_success);
		mutex_lock(&priv->mutex);
		priv->switch_rxon.switch_in_progress = false;
		mutex_unlock(&priv->mutex);
	}
}

#ifdef CONFIG_IWLWIFI_DEBUG
void iwl_print_rx_config_cmd(struct iwl_priv *priv,
			     struct iwl_rxon_context *ctx)
{
	struct iwl_rxon_cmd *rxon = &ctx->staging;

	IWL_DEBUG_RADIO(priv, "RX CONFIG:\n");
	iwl_print_hex_dump(priv, IWL_DL_RADIO, (u8 *) rxon, sizeof(*rxon));
	IWL_DEBUG_RADIO(priv, "u16 channel: 0x%x\n", le16_to_cpu(rxon->channel));
	IWL_DEBUG_RADIO(priv, "u32 flags: 0x%08X\n", le32_to_cpu(rxon->flags));
	IWL_DEBUG_RADIO(priv, "u32 filter_flags: 0x%08x\n",
			le32_to_cpu(rxon->filter_flags));
	IWL_DEBUG_RADIO(priv, "u8 dev_type: 0x%x\n", rxon->dev_type);
	IWL_DEBUG_RADIO(priv, "u8 ofdm_basic_rates: 0x%02x\n",
			rxon->ofdm_basic_rates);
	IWL_DEBUG_RADIO(priv, "u8 cck_basic_rates: 0x%02x\n", rxon->cck_basic_rates);
	IWL_DEBUG_RADIO(priv, "u8[6] node_addr: %pM\n", rxon->node_addr);
	IWL_DEBUG_RADIO(priv, "u8[6] bssid_addr: %pM\n", rxon->bssid_addr);
	IWL_DEBUG_RADIO(priv, "u16 assoc_id: 0x%x\n", le16_to_cpu(rxon->assoc_id));
}
#endif

void iwlagn_fw_error(struct iwl_priv *priv, bool ondemand)
{
	unsigned int reload_msec;
	unsigned long reload_jiffies;

	/* Set the FW error flag -- cleared on iwl_down */
	set_bit(STATUS_FW_ERROR, &priv->status);

	/* Cancel currently queued command. */
	clear_bit(STATUS_HCMD_ACTIVE, &priv->status);

	/* Keep the restart process from trying to send host
	 * commands by clearing the ready bit */
	clear_bit(STATUS_READY, &priv->status);

	wake_up_interruptible(&priv->wait_command_queue);

	if (!ondemand) {
		/*
		 * If firmware keep reloading, then it indicate something
		 * serious wrong and firmware having problem to recover
		 * from it. Instead of keep trying which will fill the syslog
		 * and hang the system, let's just stop it
		 */
		reload_jiffies = jiffies;
		reload_msec = jiffies_to_msecs((long) reload_jiffies -
					(long) priv->reload_jiffies);
		priv->reload_jiffies = reload_jiffies;
		if (reload_msec <= IWL_MIN_RELOAD_DURATION) {
			priv->reload_count++;
			if (priv->reload_count >= IWL_MAX_CONTINUE_RELOAD_CNT) {
				IWL_ERR(priv, "BUG_ON, Stop restarting\n");
				return;
			}
		} else
			priv->reload_count = 0;
	}

	if (!test_bit(STATUS_EXIT_PENDING, &priv->status)) {
		if (priv->cfg->mod_params->restart_fw) {
			IWL_DEBUG(priv, IWL_DL_FW_ERRORS,
				  "Restarting adapter due to uCode error.\n");
			queue_work(priv->workqueue, &priv->restart);
		} else
			IWL_DEBUG(priv, IWL_DL_FW_ERRORS,
				  "Detected FW error, but not restarting\n");
	}
}

/**
 * iwl_irq_handle_error - called for HW or SW error interrupt from card
 */
void iwl_irq_handle_error(struct iwl_priv *priv)
{
	/* W/A for WiFi/WiMAX coex and WiMAX own the RF */
	if (priv->cfg->internal_wimax_coex &&
	    (!(iwl_read_prph(priv, APMG_CLK_CTRL_REG) &
			APMS_CLK_VAL_MRB_FUNC_MODE) ||
	     (iwl_read_prph(priv, APMG_PS_CTRL_REG) &
			APMG_PS_CTRL_VAL_RESET_REQ))) {
		/*
		 * Keep the restart process from trying to send host
		 * commands by clearing the ready bit.
		 */
		clear_bit(STATUS_READY, &priv->status);
		clear_bit(STATUS_HCMD_ACTIVE, &priv->status);
		wake_up_interruptible(&priv->wait_command_queue);
		IWL_ERR(priv, "RF is used by WiMAX\n");
		return;
	}

	IWL_ERR(priv, "Loaded firmware version: %s\n",
		priv->hw->wiphy->fw_version);

	priv->cfg->ops->lib->dump_nic_error_log(priv);
	if (priv->cfg->ops->lib->dump_csr)
		priv->cfg->ops->lib->dump_csr(priv);
	if (priv->cfg->ops->lib->dump_fh)
		priv->cfg->ops->lib->dump_fh(priv, NULL, false);
	priv->cfg->ops->lib->dump_nic_event_log(priv, false, NULL, false);
#ifdef CONFIG_IWLWIFI_DEBUG
	if (iwl_get_debug_level(priv) & IWL_DL_FW_ERRORS)
		iwl_print_rx_config_cmd(priv,
					&priv->contexts[IWL_RXON_CTX_BSS]);
#endif

	iwlagn_fw_error(priv, false);
}

static int iwl_apm_stop_master(struct iwl_priv *priv)
{
	int ret = 0;

	/* stop device's busmaster DMA activity */
	iwl_set_bit(priv, CSR_RESET, CSR_RESET_REG_FLAG_STOP_MASTER);

	ret = iwl_poll_bit(priv, CSR_RESET, CSR_RESET_REG_FLAG_MASTER_DISABLED,
			CSR_RESET_REG_FLAG_MASTER_DISABLED, 100);
	if (ret)
		IWL_WARN(priv, "Master Disable Timed Out, 100 usec\n");

	IWL_DEBUG_INFO(priv, "stop master\n");

	return ret;
}

void iwl_apm_stop(struct iwl_priv *priv)
{
	IWL_DEBUG_INFO(priv, "Stop card, put in low power state\n");

	/* Stop device's DMA activity */
	iwl_apm_stop_master(priv);

	/* Reset the entire device */
	iwl_set_bit(priv, CSR_RESET, CSR_RESET_REG_FLAG_SW_RESET);

	udelay(10);

	/*
	 * Clear "initialization complete" bit to move adapter from
	 * D0A* (powered-up Active) --> D0U* (Uninitialized) state.
	 */
	iwl_clear_bit(priv, CSR_GP_CNTRL, CSR_GP_CNTRL_REG_FLAG_INIT_DONE);
}


/*
 * Start up NIC's basic functionality after it has been reset
 * (e.g. after platform boot, or shutdown via iwl_apm_stop())
 * NOTE:  This does not load uCode nor start the embedded processor
 */
int iwl_apm_init(struct iwl_priv *priv)
{
	int ret = 0;
	u16 lctl;

	IWL_DEBUG_INFO(priv, "Init card's basic functions\n");

	/*
	 * Use "set_bit" below rather than "write", to preserve any hardware
	 * bits already set by default after reset.
	 */

	/* Disable L0S exit timer (platform NMI Work/Around) */
	iwl_set_bit(priv, CSR_GIO_CHICKEN_BITS,
			  CSR_GIO_CHICKEN_BITS_REG_BIT_DIS_L0S_EXIT_TIMER);

	/*
	 * Disable L0s without affecting L1;
	 *  don't wait for ICH L0s (ICH bug W/A)
	 */
	iwl_set_bit(priv, CSR_GIO_CHICKEN_BITS,
			  CSR_GIO_CHICKEN_BITS_REG_BIT_L1A_NO_L0S_RX);

	/* Set FH wait threshold to maximum (HW error during stress W/A) */
	iwl_set_bit(priv, CSR_DBG_HPET_MEM_REG, CSR_DBG_HPET_MEM_REG_VAL