drivers/net/wireless/ath/ath9k/wow.c - maze/linux - Git at Google

 /*
  * Copyright (c) 2013 Qualcomm Atheros, Inc.
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
  * copyright notice and this permission notice appear in all copies.
  *
  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */

 #include "ath9k.h"

 static const struct wiphy_wowlan_support ath9k_wowlan_support = {
 	.flags = WIPHY_WOWLAN_MAGIC_PKT | WIPHY_WOWLAN_DISCONNECT,
 	.n_patterns = MAX_NUM_USER_PATTERN,
 	.pattern_min_len = 1,
 	.pattern_max_len = MAX_PATTERN_SIZE,
 };

 static void ath9k_wow_map_triggers(struct ath_softc *sc,
 				   struct cfg80211_wowlan *wowlan,
 				   u32 *wow_triggers)
 {
 	if (wowlan->disconnect)
 		*wow_triggers |= AH_WOW_LINK_CHANGE |
 				 AH_WOW_BEACON_MISS;
 	if (wowlan->magic_pkt)
 		*wow_triggers |= AH_WOW_MAGIC_PATTERN_EN;

 	if (wowlan->n_patterns)
 		*wow_triggers |= AH_WOW_USER_PATTERN_EN;

 	sc->wow_enabled = *wow_triggers;

 }

 static void ath9k_wow_add_disassoc_deauth_pattern(struct ath_softc *sc)
 {
 	struct ath_hw *ah = sc->sc_ah;
 	struct ath_common *common = ath9k_hw_common(ah);
 	int pattern_count = 0;
 	int i, byte_cnt;
 	u8 dis_deauth_pattern[MAX_PATTERN_SIZE];
 	u8 dis_deauth_mask[MAX_PATTERN_SIZE];

 	memset(dis_deauth_pattern, 0, MAX_PATTERN_SIZE);
 	memset(dis_deauth_mask, 0, MAX_PATTERN_SIZE);

 	/*
 	 * Create Dissassociate / Deauthenticate packet filter
 	 *
 	 *     2 bytes        2 byte    6 bytes   6 bytes  6 bytes
 	 *  +--------------+----------+---------+--------+--------+----
 	 *  + Frame Control+ Duration +   DA    +  SA    +  BSSID +
 	 *  +--------------+----------+---------+--------+--------+----
 	 *
 	 * The above is the management frame format for disassociate/
 	 * deauthenticate pattern, from this we need to match the first byte
 	 * of 'Frame Control' and DA, SA, and BSSID fields
 	 * (skipping 2nd byte of FC and Duration feild.
 	 *
 	 * Disassociate pattern
 	 * --------------------
 	 * Frame control = 00 00 1010
 	 * DA, SA, BSSID = x:x:x:x:x:x
 	 * Pattern will be A0000000 | x:x:x:x:x:x | x:x:x:x:x:x
 	 *			    | x:x:x:x:x:x  -- 22 bytes
 	 *
 	 * Deauthenticate pattern
 	 * ----------------------
 	 * Frame control = 00 00 1100
 	 * DA, SA, BSSID = x:x:x:x:x:x
 	 * Pattern will be C0000000 | x:x:x:x:x:x | x:x:x:x:x:x
 	 *			    | x:x:x:x:x:x  -- 22 bytes
 	 */

 	/* Create Disassociate Pattern first */

 	byte_cnt = 0;

 	/* Fill out the mask with all FF's */

 	for (i = 0; i < MAX_PATTERN_MASK_SIZE; i++)
 		dis_deauth_mask[i] = 0xff;

 	/* copy the first byte of frame control field */
 	dis_deauth_pattern[byte_cnt] = 0xa0;
 	byte_cnt++;

 	/* skip 2nd byte of frame control and Duration field */
 	byte_cnt += 3;

 	/*
 	 * need not match the destination mac address, it can be a broadcast
 	 * mac address or an unicast to this station
 	 */
 	byte_cnt += 6;

 	/* copy the source mac address */
 	memcpy((dis_deauth_pattern + byte_cnt), common->curbssid, ETH_ALEN);

 	byte_cnt += 6;

 	/* copy the bssid, its same as the source mac address */

 	memcpy((dis_deauth_pattern + byte_cnt), common->curbssid, ETH_ALEN);

 	/* Create Disassociate pattern mask */

 	dis_deauth_mask[0] = 0xfe;
 	dis_deauth_mask[1] = 0x03;
 	dis_deauth_mask[2] = 0xc0;

 	ath_dbg(common, WOW, "Adding disassoc/deauth patterns for WoW\n");

 	ath9k_hw_wow_apply_pattern(ah, dis_deauth_pattern, dis_deauth_mask,
 				   pattern_count, byte_cnt);

 	pattern_count++;
 	/*
 	 * for de-authenticate pattern, only the first byte of the frame
 	 * control field gets changed from 0xA0 to 0xC0
 	 */
 	dis_deauth_pattern[0] = 0xC0;

 	ath9k_hw_wow_apply_pattern(ah, dis_deauth_pattern, dis_deauth_mask,
 				   pattern_count, byte_cnt);

 }

 static void ath9k_wow_add_pattern(struct ath_softc *sc,
 				  struct cfg80211_wowlan *wowlan)
 {
 	struct ath_hw *ah = sc->sc_ah;
 	struct ath9k_wow_pattern *wow_pattern = NULL;
 	struct cfg80211_pkt_pattern *patterns = wowlan->patterns;
 	int mask_len;
 	s8 i = 0;

 	if (!wowlan->n_patterns)
 		return;

 	/*
 	 * Add the new user configured patterns
 	 */
 	for (i = 0; i < wowlan->n_patterns; i++) {

 		wow_pattern = kzalloc(sizeof(*wow_pattern), GFP_KERNEL);

 		if (!wow_pattern)
 			return;

 		/*
 		 * TODO: convert the generic user space pattern to
 		 * appropriate chip specific/802.11 pattern.
 		 */

 		mask_len = DIV_ROUND_UP(wowlan->patterns[i].pattern_len, 8);
 		memset(wow_pattern->pattern_bytes, 0, MAX_PATTERN_SIZE);
 		memset(wow_pattern->mask_bytes, 0, MAX_PATTERN_SIZE);
 		memcpy(wow_pattern->pattern_bytes, patterns[i].pattern,
 		       patterns[i].pattern_len);
 		memcpy(wow_pattern->mask_bytes, patterns[i].mask, mask_len);
 		wow_pattern->pattern_len = patterns[i].pattern_len;

 		/*
 		 * just need to take care of deauth and disssoc pattern,
 		 * make sure we don't overwrite them.
 		 */

 		ath9k_hw_wow_apply_pattern(ah, wow_pattern->pattern_bytes,
 					   wow_pattern->mask_bytes,
 					   i + 2,
 					   wow_pattern->pattern_len);
 		kfree(wow_pattern);

 	}

 }

 int ath9k_suspend(struct ieee80211_hw *hw,
 		  struct cfg80211_wowlan *wowlan)
 {
 	struct ath_softc *sc = hw->priv;
 	struct ath_hw *ah = sc->sc_ah;
 	struct ath_common *common = ath9k_hw_common(ah);
 	u32 wow_triggers_enabled = 0;
 	int ret = 0;

 	mutex_lock(&sc->mutex);

 	ath_cancel_work(sc);
 	ath_stop_ani(sc);

 	if (test_bit(ATH_OP_INVALID, &common->op_flags)) {
 		ath_dbg(common, ANY, "Device not present\n");
 		ret = -EINVAL;
 		goto fail_wow;
 	}

 	if (WARN_ON(!wowlan)) {
 		ath_dbg(common, WOW, "None of the WoW triggers enabled\n");
 		ret = -EINVAL;
 		goto fail_wow;
 	}

 	if (!device_can_wakeup(sc->dev)) {
 		ath_dbg(common, WOW, "device_can_wakeup failed, WoW is not enabled\n");
 		ret = 1;
 		goto fail_wow;
 	}

 	/*
 	 * none of the sta vifs are associated
 	 * and we are not currently handling multivif
 	 * cases, for instance we have to seperately
 	 * configure 'keep alive frame' for each
 	 * STA.
 	 */

 	if (!test_bit(ATH_OP_PRIM_STA_VIF, &common->op_flags)) {
 		ath_dbg(common, WOW, "None of the STA vifs are associated\n");
 		ret = 1;
 		goto fail_wow;
 	}

 	if (sc->nvifs > 1) {
 		ath_dbg(common, WOW, "WoW for multivif is not yet supported\n");
 		ret = 1;
 		goto fail_wow;
 	}

 	ath9k_wow_map_triggers(sc, wowlan, &wow_triggers_enabled);

 	ath_dbg(common, WOW, "WoW triggers enabled 0x%x\n",
 		wow_triggers_enabled);

 	ath9k_ps_wakeup(sc);

 	ath9k_stop_btcoex(sc);

 	/*
 	 * Enable wake up on recieving disassoc/deauth
 	 * frame by default.
 	 */
 	ath9k_wow_add_disassoc_deauth_pattern(sc);

 	if (wow_triggers_enabled & AH_WOW_USER_PATTERN_EN)
 		ath9k_wow_add_pattern(sc, wowlan);

 	spin_lock_bh(&sc->sc_pcu_lock);
 	/*
 	 * To avoid false wake, we enable beacon miss interrupt only
 	 * when we go to sleep. We save the current interrupt mask
 	 * so we can restore it after the system wakes up
 	 */
 	sc->wow_intr_before_sleep = ah->imask;
 	ah->imask &= ~ATH9K_INT_GLOBAL;
 	ath9k_hw_disable_interrupts(ah);
 	ah->imask = ATH9K_INT_BMISS | ATH9K_INT_GLOBAL;
 	ath9k_hw_set_interrupts(ah);
 	ath9k_hw_enable_interrupts(ah);

 	spin_unlock_bh(&sc->sc_pcu_lock);

 	/*
 	 * we can now sync irq and kill any running tasklets, since we already
 	 * disabled interrupts and not holding a spin lock
 	 */
 	synchronize_irq(sc->irq);
 	tasklet_kill(&sc->intr_tq);

 	ath9k_hw_wow_enable(ah, wow_triggers_enabled);

 	ath9k_ps_restore(sc);
 	ath_dbg(common, ANY, "WoW enabled in ath9k\n");
 	atomic_inc(&sc->wow_sleep_proc_intr);

 fail_wow:
 	mutex_unlock(&sc->mutex);
 	return ret;
 }

 int ath9k_resume(struct ieee80211_hw *hw)
 {
 	struct ath_softc *sc = hw->priv;
 	struct ath_hw *ah = sc->sc_ah;
 	struct ath_common *common = ath9k_hw_common(ah);
 	u32 wow_status;

 	mutex_lock(&sc->mutex);

 	ath9k_ps_wakeup(sc);

 	spin_lock_bh(&sc->sc_pcu_lock);

 	ath9k_hw_disable_interrupts(ah);
 	ah->imask = sc->wow_intr_before_sleep;
 	ath9k_hw_set_interrupts(ah);
 	ath9k_hw_enable_interrupts(ah);

 	spin_unlock_bh(&sc->sc_pcu_lock);

 	wow_status = ath9k_hw_wow_wakeup(ah);

 	if (atomic_read(&sc->wow_got_bmiss_intr) == 0) {
 		/*
 		 * some devices may not pick beacon miss
 		 * as the reason they woke up so we add
 		 * that here for that shortcoming.
 		 */
 		wow_status |= AH_WOW_BEACON_MISS;
 		atomic_dec(&sc->wow_got_bmiss_intr);
 		ath_dbg(common, ANY, "Beacon miss interrupt picked up during WoW sleep\n");
 	}

 	atomic_dec(&sc->wow_sleep_proc_intr);

 	if (wow_status) {
 		ath_dbg(common, ANY, "Waking up due to WoW triggers %s with WoW status = %x\n",
 			ath9k_hw_wow_event_to_string(wow_status), wow_status);
 	}

 	ath_restart_work(sc);
 	ath9k_start_btcoex(sc);

 	ath9k_ps_restore(sc);
 	mutex_unlock(&sc->mutex);

 	return 0;
 }

 void ath9k_set_wakeup(struct ieee80211_hw *hw, bool enabled)
 {
 	struct ath_softc *sc = hw->priv;

 	mutex_lock(&sc->mutex);
 	device_init_wakeup(sc->dev, 1);
 	device_set_wakeup_enable(sc->dev, enabled);
 	mutex_unlock(&sc->mutex);
 }

 void ath9k_init_wow(struct ieee80211_hw *hw)
 {
 	struct ath_softc *sc = hw->priv;

 	if ((sc->sc_ah->caps.hw_caps & ATH9K_HW_WOW_DEVICE_CAPABLE) &&
 	    (sc->driver_data & ATH9K_PCI_WOW) &&
 	    device_can_wakeup(sc->dev))
 		hw->wiphy->wowlan = &ath9k_wowlan_support;

 	atomic_set(&sc->wow_sleep_proc_intr, -1);
 	atomic_set(&sc->wow_got_bmiss_intr, -1);
 }
	/*
	* Copyright (c) 2013 Qualcomm Atheros, Inc.
	*
	* Permission to use, copy, modify, and/or distribute this software for any
	* purpose with or without fee is hereby granted, provided that the above
	* copyright notice and this permission notice appear in all copies.
	*
	* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
	* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
	* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
	* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
	* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
	* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
	* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
	*/

	#include "ath9k.h"

	static const struct wiphy_wowlan_support ath9k_wowlan_support = {
	.flags = WIPHY_WOWLAN_MAGIC_PKT \| WIPHY_WOWLAN_DISCONNECT,
	.n_patterns = MAX_NUM_USER_PATTERN,
	.pattern_min_len = 1,
	.pattern_max_len = MAX_PATTERN_SIZE,
	};

	static void ath9k_wow_map_triggers(struct ath_softc *sc,
	struct cfg80211_wowlan *wowlan,
	u32 *wow_triggers)
	{
	if (wowlan->disconnect)
	*wow_triggers \|= AH_WOW_LINK_CHANGE \|
	AH_WOW_BEACON_MISS;
	if (wowlan->magic_pkt)
	*wow_triggers \|= AH_WOW_MAGIC_PATTERN_EN;

	if (wowlan->n_patterns)
	*wow_triggers \|= AH_WOW_USER_PATTERN_EN;

	sc->wow_enabled = *wow_triggers;

	}

	static void ath9k_wow_add_disassoc_deauth_pattern(struct ath_softc *sc)
	{
	struct ath_hw *ah = sc->sc_ah;
	struct ath_common *common = ath9k_hw_common(ah);
	int pattern_count = 0;
	int i, byte_cnt;
	u8 dis_deauth_pattern[MAX_PATTERN_SIZE];
	u8 dis_deauth_mask[MAX_PATTERN_SIZE];

	memset(dis_deauth_pattern, 0, MAX_PATTERN_SIZE);
	memset(dis_deauth_mask, 0, MAX_PATTERN_SIZE);

	/*
	* Create Dissassociate / Deauthenticate packet filter
	*
	* 2 bytes 2 byte 6 bytes 6 bytes 6 bytes
	* +--------------+----------+---------+--------+--------+----
	* + Frame Control+ Duration + DA + SA + BSSID +
	* +--------------+----------+---------+--------+--------+----
	*
	* The above is the management frame format for disassociate/
	* deauthenticate pattern, from this we need to match the first byte
	* of 'Frame Control' and DA, SA, and BSSID fields
	* (skipping 2nd byte of FC and Duration feild.
	*
	* Disassociate pattern
	* --------------------
	* Frame control = 00 00 1010
	* DA, SA, BSSID = x:x:x:x:x:x
	* Pattern will be A0000000 \| x:x:x:x:x:x \| x:x:x:x:x:x
	* \| x:x:x:x:x:x -- 22 bytes
	*
	* Deauthenticate pattern
	* ----------------------
	* Frame control = 00 00 1100
	* DA, SA, BSSID = x:x:x:x:x:x
	* Pattern will be C0000000 \| x:x:x:x:x:x \| x:x:x:x:x:x
	* \| x:x:x:x:x:x -- 22 bytes
	*/

	/* Create Disassociate Pattern first */

	byte_cnt = 0;

	/* Fill out the mask with all FF's */

	for (i = 0; i < MAX_PATTERN_MASK_SIZE; i++)
	dis_deauth_mask[i] = 0xff;

	/* copy the first byte of frame control field */
	dis_deauth_pattern[byte_cnt] = 0xa0;
	byte_cnt++;

	/* skip 2nd byte of frame control and Duration field */
	byte_cnt += 3;

	/*
	* need not match the destination mac address, it can be a broadcast
	* mac address or an unicast to this station
	*/
	byte_cnt += 6;

	/* copy the source mac address */
	memcpy((dis_deauth_pattern + byte_cnt), common->curbssid, ETH_ALEN);

	byte_cnt += 6;

	/* copy the bssid, its same as the source mac address */

	memcpy((dis_deauth_pattern + byte_cnt), common->curbssid, ETH_ALEN);

	/* Create Disassociate pattern mask */

	dis_deauth_mask[0] = 0xfe;
	dis_deauth_mask[1] = 0x03;
	dis_deauth_mask[2] = 0xc0;

	ath_dbg(common, WOW, "Adding disassoc/deauth patterns for WoW\n");

	ath9k_hw_wow_apply_pattern(ah, dis_deauth_pattern, dis_deauth_mask,
	pattern_count, byte_cnt);

	pattern_count++;
	/*
	* for de-authenticate pattern, only the first byte of the frame
	* control field gets changed from 0xA0 to 0xC0
	*/
	dis_deauth_pattern[0] = 0xC0;

	ath9k_hw_wow_apply_pattern(ah, dis_deauth_pattern, dis_deauth_mask,
	pattern_count, byte_cnt);

	}

	static void ath9k_wow_add_pattern(struct ath_softc *sc,
	struct cfg80211_wowlan *wowlan)
	{
	struct ath_hw *ah = sc->sc_ah;
	struct ath9k_wow_pattern *wow_pattern = NULL;
	struct cfg80211_pkt_pattern *patterns = wowlan->patterns;
	int mask_len;
	s8 i = 0;

	if (!wowlan->n_patterns)
	return;

	/*
	* Add the new user configured patterns
	*/
	for (i = 0; i < wowlan->n_patterns; i++) {

	wow_pattern = kzalloc(sizeof(*wow_pattern), GFP_KERNEL);

	if (!wow_pattern)
	return;

	/*
	* TODO: convert the generic user space pattern to
	* appropriate chip specific/802.11 pattern.
	*/

	mask_len = DIV_ROUND_UP(wowlan->patterns[i].pattern_len, 8);
	memset(wow_pattern->pattern_bytes, 0, MAX_PATTERN_SIZE);
	memset(wow_pattern->mask_bytes, 0, MAX_PATTERN_SIZE);
	memcpy(wow_pattern->pattern_bytes, patterns[i].pattern,
	patterns[i].pattern_len);
	memcpy(wow_pattern->mask_bytes, patterns[i].mask, mask_len);
	wow_pattern->pattern_len = patterns[i].pattern_len;

	/*
	* just need to take care of deauth and disssoc pattern,
	* make sure we don't overwrite them.
	*/

	ath9k_hw_wow_apply_pattern(ah, wow_pattern->pattern_bytes,
	wow_pattern->mask_bytes,
	i + 2,
	wow_pattern->pattern_len);
	kfree(wow_pattern);

	}

	}

	int ath9k_suspend(struct ieee80211_hw *hw,
	struct cfg80211_wowlan *wowlan)
	{
	struct ath_softc *sc = hw->priv;
	struct ath_hw *ah = sc->sc_ah;
	struct ath_common *common = ath9k_hw_common(ah);
	u32 wow_triggers_enabled = 0;
	int ret = 0;

	mutex_lock(&sc->mutex);

	ath_cancel_work(sc);
	ath_stop_ani(sc);

	if (test_bit(ATH_OP_INVALID, &common->op_flags)) {
	ath_dbg(common, ANY, "Device not present\n");
	ret = -EINVAL;
	goto fail_wow;
	}

	if (WARN_ON(!wowlan)) {
	ath_dbg(common, WOW, "None of the WoW triggers enabled\n");
	ret = -EINVAL;
	goto fail_wow;
	}

	if (!device_can_wakeup(sc->dev)) {
	ath_dbg(common, WOW, "device_can_wakeup failed, WoW is not enabled\n");
	ret = 1;
	goto fail_wow;
	}

	/*
	* none of the sta vifs are associated
	* and we are not currently handling multivif
	* cases, for instance we have to seperately
	* configure 'keep alive frame' for each
	* STA.
	*/

	if (!test_bit(ATH_OP_PRIM_STA_VIF, &common->op_flags)) {
	ath_dbg(common, WOW, "None of the STA vifs are associated\n");
	ret = 1;
	goto fail_wow;
	}

	if (sc->nvifs > 1) {
	ath_dbg(common, WOW, "WoW for multivif is not yet supported\n");
	ret = 1;
	goto fail_wow;
	}

	ath9k_wow_map_triggers(sc, wowlan, &wow_triggers_enabled);

	ath_dbg(common, WOW, "WoW triggers enabled 0x%x\n",
	wow_triggers_enabled);

	ath9k_ps_wakeup(sc);

	ath9k_stop_btcoex(sc);

	/*
	* Enable wake up on recieving disassoc/deauth
	* frame by default.
	*/
	ath9k_wow_add_disassoc_deauth_pattern(sc);

	if (wow_triggers_enabled & AH_WOW_USER_PATTERN_EN)
	ath9k_wow_add_pattern(sc, wowlan);

	spin_lock_bh(&sc->sc_pcu_lock);
	/*
	* To avoid false wake, we enable beacon miss interrupt only
	* when we go to sleep. We save the current interrupt mask
	* so we can restore it after the system wakes up
	*/
	sc->wow_intr_before_sleep = ah->imask;
	ah->imask &= ~ATH9K_INT_GLOBAL;
	ath9k_hw_disable_interrupts(ah);
	ah->imask = ATH9K_INT_BMISS \| ATH9K_INT_GLOBAL;
	ath9k_hw_set_interrupts(ah);
	ath9k_hw_enable_interrupts(ah);

	spin_unlock_bh(&sc->sc_pcu_lock);

	/*
	* we can now sync irq and kill any running tasklets, since we already
	* disabled interrupts and not holding a spin lock
	*/
	synchronize_irq(sc->irq);
	tasklet_kill(&sc->intr_tq);

	ath9k_hw_wow_enable(ah, wow_triggers_enabled);

	ath9k_ps_restore(sc);
	ath_dbg(common, ANY, "WoW enabled in ath9k\n");
	atomic_inc(&sc->wow_sleep_proc_intr);

	fail_wow:
	mutex_unlock(&sc->mutex);
	return ret;
	}

	int ath9k_resume(struct ieee80211_hw *hw)
	{
	struct ath_softc *sc = hw->priv;
	struct ath_hw *ah = sc->sc_ah;
	struct ath_common *common = ath9k_hw_common(ah);
	u32 wow_status;

	mutex_lock(&sc->mutex);

	ath9k_ps_wakeup(sc);

	spin_lock_bh(&sc->sc_pcu_lock);

	ath9k_hw_disable_interrupts(ah);
	ah->imask = sc->wow_intr_before_sleep;
	ath9k_hw_set_interrupts(ah);
	ath9k_hw_enable_interrupts(ah);

	spin_unlock_bh(&sc->sc_pcu_lock);

	wow_status = ath9k_hw_wow_wakeup(ah);

	if (atomic_read(&sc->wow_got_bmiss_intr) == 0) {
	/*
	* some devices may not pick beacon miss
	* as the reason they woke up so we add
	* that here for that shortcoming.
	*/
	wow_status \|= AH_WOW_BEACON_MISS;
	atomic_dec(&sc->wow_got_bmiss_intr);
	ath_dbg(common, ANY, "Beacon miss interrupt picked up during WoW sleep\n");
	}

	atomic_dec(&sc->wow_sleep_proc_intr);

	if (wow_status) {
	ath_dbg(common, ANY, "Waking up due to WoW triggers %s with WoW status = %x\n",
	ath9k_hw_wow_event_to_string(wow_status), wow_status);
	}

	ath_restart_work(sc);
	ath9k_start_btcoex(sc);

	ath9k_ps_restore(sc);
	mutex_unlock(&sc->mutex);

	return 0;
	}

	void ath9k_set_wakeup(struct ieee80211_hw *hw, bool enabled)
	{
	struct ath_softc *sc = hw->priv;

	mutex_lock(&sc->mutex);
	device_init_wakeup(sc->dev, 1);
	device_set_wakeup_enable(sc->dev, enabled);
	mutex_unlock(&sc->mutex);
	}

	void ath9k_init_wow(struct ieee80211_hw *hw)
	{
	struct ath_softc *sc = hw->priv;

	if ((sc->sc_ah->caps.hw_caps & ATH9K_HW_WOW_DEVICE_CAPABLE) &&
	(sc->driver_data & ATH9K_PCI_WOW) &&
	device_can_wakeup(sc->dev))
	hw->wiphy->wowlan = &ath9k_wowlan_support;

	atomic_set(&sc->wow_sleep_proc_intr, -1);
	atomic_set(&sc->wow_got_bmiss_intr, -1);
	}