/******************************************************************************
*
* GPL LICENSE SUMMARY
*
* Copyright(c) 2008 - 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.GPL.
*
* Contact Information:
* Intel Linux Wireless <ilw@linux.intel.com>
* Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
*****************************************************************************/
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/etherdevice.h>
#include <net/mac80211.h>
#include "iwl-eeprom.h"
#include "iwl-dev.h"
#include "iwl-core.h"
#include "iwl-sta.h"
#include "iwl-io.h"
#include "iwl-helpers.h"
/* For active scan, listen ACTIVE_DWELL_TIME (msec) on each channel after
* sending probe req. This should be set long enough to hear probe responses
* from more than one AP. */
#define IWL_ACTIVE_DWELL_TIME_24 (30) /* all times in msec */
#define IWL_ACTIVE_DWELL_TIME_52 (20)
#define IWL_ACTIVE_DWELL_FACTOR_24GHZ (3)
#define IWL_ACTIVE_DWELL_FACTOR_52GHZ (2)
/* For passive scan, listen PASSIVE_DWELL_TIME (msec) on each channel.
* Must be set longer than active dwell time.
* For the most reliable scan, set > AP beacon interval (typically 100msec). */
#define IWL_PASSIVE_DWELL_TIME_24 (20) /* all times in msec */
#define IWL_PASSIVE_DWELL_TIME_52 (10)
#define IWL_PASSIVE_DWELL_BASE (100)
#define IWL_CHANNEL_TUNE_TIME 5
/**
* iwl_scan_cancel - Cancel any currently executing HW scan
*
* NOTE: priv->mutex is not required before calling this function
*/
int iwl_scan_cancel(struct iwl_priv *priv)
{
if (!test_bit(STATUS_SCAN_HW, &priv->status)) {
clear_bit(STATUS_SCANNING, &priv->status);
return 0;
}
if (test_bit(STATUS_SCANNING, &priv->status)) {
if (!test_and_set_bit(STATUS_SCAN_ABORTING, &priv->status)) {
IWL_DEBUG_SCAN(priv, "Queuing scan abort.\n");
queue_work(priv->workqueue, &priv->abort_scan);
} else
IWL_DEBUG_SCAN(priv, "Scan abort already in progress.\n");
return test_bit(STATUS_SCANNING, &priv->status);
}
return 0;
}
EXPORT_SYMBOL(iwl_scan_cancel);
/**
* iwl_scan_cancel_timeout - Cancel any currently executing HW scan
* @ms: amount of time to wait (in milliseconds) for scan to abort
*
* NOTE: priv->mutex must be held before calling this function
*/
int iwl_scan_cancel_timeout(struct iwl_priv *priv, unsigned long ms)
{
unsigned long now = jiffies;
int ret;
ret = iwl_scan_cancel(priv);
if (ret && ms) {
mutex_unlock(&priv->mutex);
while (!time_after(jiffies, now + msecs_to_jiffies(ms)) &&
test_bit(STATUS_SCANNING, &priv->status))
msleep(1);
mutex_lock(&priv->mutex);
return test_bit(STATUS_SCANNING, &priv->status);
}
return ret;
}
EXPORT_SYMBOL(iwl_scan_cancel_timeout);
static int iwl_send_scan_abort(struct iwl_priv *priv)
{
int ret = 0;
struct iwl_rx_packet *pkt;
struct iwl_host_cmd cmd = {
.id = REPLY_SCAN_ABORT_CMD,
.flags = CMD_WANT_SKB,
};
/* If there isn't a scan actively going on in the hardware
* then we are in between scan bands and not actually
* actively scanning, so don't send the abort command */
if (!test_bit(STATUS_SCAN_HW, &priv->status)) {
clear_bit(STATUS_SCAN_ABORTING, &priv->status);
return 0;
}
ret = iwl_send_cmd_sync(priv, &cmd);
if (ret) {
clear_bit(STATUS_SCAN_ABORTING, &priv->status);
return ret;
}
pkt = (struct iwl_rx_packet *)cmd.reply_page;
if (pkt->u.status != CAN_ABORT_STATUS) {
/* The scan abort will return 1 for success or
* 2 for "failure". A failure condition can be
* due to simply not being in an active scan which
* can occur if we send the scan abort before we
* the microcode has notified us that a scan is
* completed. */
IWL_DEBUG_INFO(priv, "SCAN_ABORT returned %d.\n", pkt->u.status);
clear_bit(STATUS_SCAN_ABORTING, &priv->status);
clear_bit(STATUS_SCAN_HW, &priv->status);
}
iwl_free_pages(priv, cmd.reply_page);
return ret;
}
/* Service response to REPLY_SCAN_CMD (0x80) */
static void iwl_rx_reply_scan(struct iwl_priv *priv,
struct iwl_rx_mem_buffer *rxb)
{
#ifdef CONFIG_IWLWIFI_DEBUG
struct iwl_rx_packet *pkt = rxb_addr(rxb);
struct iwl_scanreq_notification *notif =
(struct iwl_scanreq_notification *)pkt->u.raw;
IWL_DEBUG_RX(priv, "Scan request status = 0x%x\n", notif->status);
#endif
}
/* Service SCAN_START_NOTIFICATION (0x82) */
static void iwl_rx_scan_start_notif(struct iwl_priv *priv,
struct iwl_rx_mem_buffer *rxb)
{
struct iwl_rx_packet *pkt = rxb_addr(rxb);
struct iwl_scanstart_notification *notif =
(struct iwl_scanstart_notification *)pkt->u.raw;
priv->scan_start_tsf = le32_to_cpu(notif->tsf_low);
IWL_DEBUG_SCAN(priv, "Scan start: "
"%d [802.11%s] "
"(TSF: 0x%08X:%08X) - %d (beacon timer %u)\n",
notif->channel,
notif->band ? "bg" : "a",
le32_to_cpu(notif->tsf_high),
le32_to_cpu(notif->tsf_low),
notif->status, notif->beacon_timer);
}
/* Service SCAN_RESULTS_NOTIFICATION (0x83) */
static void iwl_rx_scan_results_notif(struct iwl_priv *priv,
struct iwl_rx_mem_buffer *rxb)
{
#ifdef CONFIG_IWLWIFI_DEBUG
struct iwl_rx_packet *pkt = rxb_addr(rxb);
struct iwl_scanresults_notification *notif =
(struct iwl_scanresults_notification *)pkt->u.raw;
IWL_DEBUG_SCAN(priv, "Scan ch.res: "
"%d [802.11%s] "
"(TSF: 0x%08X:%08X) - %d "
"elapsed=%lu usec\n",
notif->channel,
notif->band ? "bg" : "a",
le32_to_cpu(notif->tsf_high),
le32_to_cpu(notif->tsf_low),
le32_to_cpu(notif->statistics[0]),
le32_to_cpu(notif->tsf_low) - priv->scan_start_tsf);
#endif
}
/* Service SCAN_COMPLETE_NOTIFICATION (0x84) */
static void iwl_rx_scan_complete_notif(struct iwl_priv *priv,
struct iwl_rx_mem_buffer *rxb)
{
#ifdef CONFIG_IWLWIFI_DEBUG
struct iwl_rx_packet *pkt = rxb_addr(rxb);
struct iwl_scancomplete_notification *scan_notif = (void *)pkt->u.raw;
IWL_DEBUG_SCAN(priv, "Scan complete: %d channels (TSF 0x%08X:%08X) - %d\n",
scan_notif->scanned_channels,
scan_notif->tsf_low,
scan_notif->tsf_high, scan_notif->status);
#endif
/* The HW is no longer scanning */
clear_bit(STATUS_SCAN_HW, &priv->status);
IWL_DEBUG_INFO(priv, "Scan on %sGHz took %dms\n",
(priv->scan_band == IEEE80211_BAND_2GHZ) ? "2.4" : "5.2",
jiffies_to_msecs(elapsed_jiffies
(priv->scan_start, jiffies)));
/*
* If a request to abort was given, or the scan did not succeed
* then we reset the scan state machine and terminate,
* re-queuing another scan if one has been requested
*/
if (test_and_clear_bit(STATUS_SCAN_ABORTING, &priv->status))
IWL_DEBUG_INFO(priv, "Aborted scan completed.\n");
IWL_DEBUG_INFO(priv, "Setting scan to off\n");
clear_bit(STATUS_SCANNING, &priv->status);
queue_work(priv->workqueue, &priv->scan_completed);
}
void iwl_setup_rx_scan_handlers(struct iwl_priv *priv)
{
/* scan handlers */
priv->rx_handlers[REPLY_SCAN_CMD] = iwl_rx_reply_scan;
priv->rx_handlers[SCAN_START_NOTIFICATION] = iwl_rx_scan_start_notif;
priv->rx_handlers[SCAN_RESULTS_NOTIFICATION] =
iwl_rx_scan_results_notif;
priv->rx_handlers[SCAN_COMPLETE_NOTIFICATION] =
iwl_rx_scan_complete_notif;
}
EXPORT_SYMBOL(iwl_setup_rx_scan_handlers);
inline u16 iwl_get_active_dwell_time(struct iwl_priv *priv,
enum ieee80211_band band,
u8 n_probes)
{
if (band == IEEE80211_BAND_5GHZ)
return IWL_ACTIVE_DWELL_TIME_52 +
IWL_ACTIVE_DWELL_FACTOR_52GHZ * (n_probes + 1);
else
return IWL_ACTIVE_DWELL_TIME_24 +
IWL_ACTIVE_DWELL_FACTOR_24GHZ * (n_probes + 1);
}
EXPORT_SYMBOL(iwl_get_active_dwell_time);
u16 iwl_get_passive_dwell_time(struct iwl_priv *priv,
enum ieee80211_band band,
struct ieee80211_vif *vif)
{
u16 passive = (band == IEEE80211_BAND_2GHZ) ?
IWL_PASSIVE_DWELL_BASE + IWL_PASSIVE_DWELL_TIME_24 :
IWL_PASSIVE_DWELL_BASE + IWL_PASSIVE_DWELL_TIME_52;
if (iwl_is_associated(priv)) {
/* If we're associated, we clamp the maximum passive
* dwell time to be 98% of the beacon interval (minus
* 2 * channel tune time) */
passive = vif ? vif->bss_conf.beacon_int : 0;
if ((passive > IWL_PASSIVE_DWELL_BASE) || !passive)
passive = IWL_PASSIVE_DWELL_BASE;
passive = (passive * 98) / 100 - IWL_CHANNEL_TUNE_TIME * 2;
}
return passive;
}
EXPORT_SYMBOL(iwl_get_passive_dwell_time);
void iwl_init_scan_params(struct iwl_priv *priv)
{
u8 ant_idx = fls(priv->hw_params.valid_tx_ant) - 1;
if (!priv->scan_tx_ant[IEEE80211_BAND_5GHZ])
priv->scan_tx_ant[IEEE80211_BAND_5GHZ] = ant_idx;
if (!priv->scan_tx_ant[IEEE80211_BAND_2GHZ])
priv->scan_tx_ant[IEEE80211_BAND_2GHZ] = ant_idx;
}
EXPORT_SYMBOL(iwl_init_scan_params);
static int iwl_scan_initiate(struct iwl_priv *priv, struct ieee80211_vif *vif)
{
WARN_ON(!mutex_is_locked(&priv->mutex));
IWL_DEBUG_INFO(priv, "Starting scan...\n");
set_bit(STATUS_SCANNING, &priv->status);
priv->is_internal_short_scan = false;
priv->scan_start = jiffies;
if (WARN_ON(!priv->cfg->ops->utils->request_scan))
return -EOPNOTSUPP;
priv->cfg->ops->utils->request_scan(priv, vif);
return 0;
}
int iwl_mac_hw_scan(struct ieee80211_hw *hw,
struct ieee80211_vif *vif,
struct cfg80211_scan_request *req)
{
struct iwl_priv *priv = hw->priv;
int ret;
IWL_DEBUG_MAC80211(priv, "enter\n");
if (req->n_channels == 0)
return -EINVAL;
mutex_lock(&priv->mutex);
if (!iwl_is_ready_rf(priv)) {
ret = -EIO;
IWL_DEBUG_MAC80211(priv, "leave - not ready or exit pending\n");
goto out_unlock;
}
if (test_bit(STATUS_SCANNING, &priv->status) &&
!priv->is_internal_short_scan) {
IWL_DEBUG_SCAN(priv, "Scan already in progress.\n");
ret = -EAGAIN;
goto out_unlock;
}
if (test_bit(STATUS_SCAN_ABORTING, &priv->status)) {
IWL_DEBUG_SCAN(priv, "Scan request while abort pending\n");
ret = -EAGAIN;
goto out_unlock;
}
/* mac80211 will only ask for one band at a time */
priv->scan_band = req->channels[0]->band;
priv->scan_request = req;
priv->scan_vif = vif;
/*
* If an internal scan is in progress, just set
* up the scan_request as per above.
*/
if (priv->is_internal_short_scan)
ret = 0;
else
ret = iwl_scan_initiate(priv, vif);
IWL_DEBUG_MAC80211(priv, "leave\n");
out_unlock:
mutex_unlock(&priv->mutex);
return ret;
}
EXPORT_SYMBOL(iwl_mac_hw_scan);
/*
* internal short scan, this function should only been called while associated.
* It will reset and tune the radio to prevent possible RF related problem
*/
void iwl_internal_short_hw_scan(struct iwl_priv *priv)
{
queue_work(priv->workqueue, &priv->start_internal_scan);
}
void iwl_bg_start_internal_scan(struct work_struct *work)
{
struct iwl_priv *priv =
container_of(work, struct iwl_priv, start_internal_scan);
mutex_lock(&priv->mutex);
if (priv->is_internal_short_scan == true) {
IWL_DEBUG_SCAN(priv, "Internal scan already in progress\n");
goto unlock;
}
if (!iwl_is_ready_rf(priv)) {
IWL_DEBUG_SCAN(priv, "not ready or exit pending\n");
goto unlock;
}
if (test_bit(STATUS_SCANNING, &priv->status)) {
IWL_DEBUG_SCAN(priv, "Scan already in progress.\n");
goto unlock;
}
if (test_bit(STATUS_SCAN_ABORTING, &priv->status)) {
IWL_DEBUG_SCAN(priv, "Scan request while abort pending\n");
goto unlock;
}
priv->scan_band = priv->band;
IWL_DEBUG_SCAN(priv, "Start internal short scan...\n");
set_bit(STATUS_SCANNING, &priv->status);
priv->is_internal_short_scan = true;
if (WARN_ON(!priv->cfg->ops->utils->request_scan))
goto unlock;
priv->cfg->ops->utils->request_scan(priv, NULL);
unlock:
mutex_unlock(&priv->mutex);
}
EXPORT_SYMBOL(iwl_bg_start_internal_scan);
void iwl_bg_scan_check(struct work_struct *data)
{
struct iwl_priv *priv =
container_of(data, struct iwl_priv, scan_check.work);
if (test_bit(STATUS_EXIT_PENDING, &priv->status))
return;
mutex_lock(&priv->mutex);
if (test_bit(STATUS_SCANNING, &priv->status) &&
!test_bit(STATUS_SCAN_ABORTING, &priv->status)) {
IWL_DEBUG_SCAN(priv, "Scan completion watchdog (%dms)\n",
jiffies_to_msecs(IWL_SCAN_CHECK_WATCHDOG));
if (!test_bit(STATUS_EXIT_PENDING, &priv->status))
iwl_send_scan_abort(priv);
}
mutex_unlock(&priv->mutex);
}
EXPORT_SYMBOL(iwl_bg_scan_check);
/**
* iwl_fill_probe_req - fill in all required fields and IE for probe request
*/
u16 iwl_fill_probe_req(struct iwl_priv *priv, struct ieee80211_mgmt *frame,
const u8 *ta, const u8 *ies, int ie_len, int left)
{
int len = 0;
u8 *pos = NULL;
/* Make sure there is enough space for the probe request,
* two mandatory IEs and the data */
left -= 24;
if (left < 0)
return 0;
frame->frame_control = cpu_to_le16(IEEE80211_STYPE_PROBE_REQ);
memcpy(frame->da, iwl_bcast_addr, ETH_ALEN);
memcpy(frame->sa, ta, ETH_ALEN);
memcpy(frame->bssid, iwl_bcast_addr, ETH_ALEN);
frame->seq_ctrl = 0;
len += 24;
/* ...next IE... */
pos = &frame->u.probe_req.variable[0];
/* fill in our indirect SSID IE */
left -= 2;
if (left < 0)
return 0;
*pos++ = WLAN_EID_SSID;
*pos++ = 0;
len += 2;
if (WARN_ON(left < ie_len))
return len;
if (ies && ie_len) {
memcpy(pos, ies, ie_len);
len += ie_len;
}
return (u16)len;
}
EXPORT_SYMBOL(iwl_fill_probe_req);
void iwl_bg_abort_scan(struct work_struct *work)
{
struct iwl_priv *priv = container_of(work, struct iwl_priv, abort_scan);
if (!test_bit(STATUS_READY, &priv->status) ||
!test_bit(STATUS_GEO_CONFIGURED, &priv->status))
return;
cancel_delayed_work(&priv->scan_check);
mutex_lock(&priv->mutex);
if (test_bit(STATUS_SCAN_ABORTING, &priv->status))
iwl_send_scan_abort(priv);
mutex_unlock(&priv->mutex);
}
EXPORT_SYMBOL(iwl_bg_abort_scan);
void iwl_bg_scan_completed(struct work_struct *work)
{
struct iwl_priv *priv =
container_of(work, struct iwl_priv, scan_completed);
bool internal = false;
IWL_DEBUG_SCAN(priv, "SCAN complete scan\n");
cancel_delayed_work(&priv->scan_check);
mutex_lock(&priv->mutex);
if (priv->is_internal_short_scan) {
priv->is_internal_short_scan = false;
IWL_DEBUG_SCAN(priv, "internal short scan completed\n");
internal = true;
} else {
priv->scan_request = NULL;
priv->scan_vif = NULL;
}
if (test_bit(STATUS_EXIT_PENDING, &priv->status))
goto out;
if (internal && priv->scan_request)
iwl_scan_initiate(priv, priv->scan_vif);
/* Since setting the TXPOWER may have been deferred while
* performing the scan, fire one off */
iwl_set_tx_power(priv, priv->tx_power_user_lmt, true);
/*
* Since setting the RXON may have been deferred while
* performing the scan, fire one off if needed
*/
if (memcmp(&priv->active_rxon,
&priv->staging_rxon, sizeof(priv->staging_rxon)))
iwlcore_commit_rxon(priv);
out:
mutex_unlock(&priv->mutex);
/*
* Do not hold mutex here since this will cause mac80211 to call
* into driver again into functions that will attempt to take
* mutex.
*/
if (!internal)
ieee80211_scan_completed(priv->hw, false);
}
EXPORT_SYMBOL(iwl_bg_scan_completed);
void iwl_setup_scan_deferred_work(struct iwl_priv *priv)
{
INIT_WORK(&priv->scan_completed, iwl_bg_scan_completed);
INIT_WORK(&priv->abort_scan, iwl_bg_abort_scan);
INIT_WORK(&priv->start_internal_scan, iwl_bg_start_internal_scan);
INIT_DELAYED_WORK(&priv->scan_check, iwl_bg_scan_check);
}
EXPORT_SYMBOL(iwl_setup_scan_deferred_work);
