/******************************************************************************
 *
 * Copyright(c) 2009-2012  Realtek Corporation.
 *
 * 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:
 * wlanfae <wlanfae@realtek.com>
 * Realtek Corporation, No. 2, Innovation Road II, Hsinchu Science Park,
 * Hsinchu 300, Taiwan.
 *
 * Larry Finger <Larry.Finger@lwfinger.net>
 *
 *****************************************************************************/

#include <linux/export.h>
#include "wifi.h"
#include "base.h"
#include "ps.h"

bool rtl_ps_enable_nic(struct ieee80211_hw *hw)
{
	struct rtl_priv *rtlpriv = rtl_priv(hw);
	struct rtl_ps_ctl *ppsc = rtl_psc(rtl_priv(hw));
	struct rtl_hal *rtlhal = rtl_hal(rtl_priv(hw));

	/*<1> reset trx ring */
	if (rtlhal->interface == INTF_PCI)
		rtlpriv->intf_ops->reset_trx_ring(hw);

	if (is_hal_stop(rtlhal))
		RT_TRACE(rtlpriv, COMP_ERR, DBG_WARNING,
			 "Driver is already down!\n");

	/*<2> Enable Adapter */
	if (rtlpriv->cfg->ops->hw_init(hw))
		return 1;
	RT_CLEAR_PS_LEVEL(ppsc, RT_RF_OFF_LEVL_HALT_NIC);

	/*<3> Enable Interrupt */
	rtlpriv->cfg->ops->enable_interrupt(hw);

	/*<enable timer> */
	rtl_watch_dog_timer_callback((unsigned long)hw);

	return true;
}
EXPORT_SYMBOL(rtl_ps_enable_nic);

bool rtl_ps_disable_nic(struct ieee80211_hw *hw)
{
	struct rtl_priv *rtlpriv = rtl_priv(hw);

	/*<1> Stop all timer */
	rtl_deinit_deferred_work(hw);

	/*<2> Disable Interrupt */
	rtlpriv->cfg->ops->disable_interrupt(hw);
	tasklet_kill(&rtlpriv->works.irq_tasklet);

	/*<3> Disable Adapter */
	rtlpriv->cfg->ops->hw_disable(hw);

	return true;
}
EXPORT_SYMBOL(rtl_ps_disable_nic);

bool rtl_ps_set_rf_state(struct ieee80211_hw *hw,
			 enum rf_pwrstate state_toset,
			 u32 changesource)
{
	struct rtl_priv *rtlpriv = rtl_priv(hw);
	struct rtl_ps_ctl *ppsc = rtl_psc(rtl_priv(hw));
	bool actionallowed = false;

	switch (state_toset) {
	case ERFON:
		ppsc->rfoff_reason &= (~changesource);

		if ((changesource == RF_CHANGE_BY_HW) &&
		    (ppsc->hwradiooff)) {
			ppsc->hwradiooff = false;
		}

		if (!ppsc->rfoff_reason) {
			ppsc->rfoff_reason = 0;
			actionallowed = true;
		}

		break;

	case ERFOFF:

		if ((changesource == RF_CHANGE_BY_HW) && !ppsc->hwradiooff) {
			ppsc->hwradiooff = true;
		}

		ppsc->rfoff_reason |= changesource;
		actionallowed = true;
		break;

	case ERFSLEEP:
		ppsc->rfoff_reason |= changesource;
		actionallowed = true;
		break;

	default:
		RT_TRACE(rtlpriv, COMP_ERR, DBG_EMERG,
			 "switch case not processed\n");
		break;
	}

	if (actionallowed)
		rtlpriv->cfg->ops->set_rf_power_state(hw, state_toset);

	return actionallowed;
}
EXPORT_SYMBOL(rtl_ps_set_rf_state);

static void _rtl_ps_inactive_ps(struct ieee80211_hw *hw)
{
	struct rtl_priv *rtlpriv = rtl_priv(hw);
	struct rtl_hal *rtlhal = rtl_hal(rtl_priv(hw));
	struct rtl_ps_ctl *ppsc = rtl_psc(rtl_priv(hw));

	ppsc->swrf_processing = true;

	if (ppsc->inactive_pwrstate == ERFON &&
	    rtlhal->interface == INTF_PCI) {
		if ((ppsc->reg_rfps_level & RT_RF_OFF_LEVL_ASPM) &&
		    RT_IN_PS_LEVEL(ppsc, RT_PS_LEVEL_ASPM) &&
		    rtlhal->interface == INTF_PCI) {
			rtlpriv->intf_ops->disable_aspm(hw);
			RT_CLEAR_PS_LEVEL(ppsc, RT_PS_LEVEL_ASPM);
		}
	}

	rtl_ps_set_rf_state(hw, ppsc->inactive_pwrstate, RF_CHANGE_BY_IPS);

	if (ppsc->inactive_pwrstate == ERFOFF &&
	    rtlhal->interface == INTF_PCI) {
		if (ppsc->reg_rfps_level & RT_RF_OFF_LEVL_ASPM &&
			!RT_IN_PS_LEVEL(ppsc, RT_PS_LEVEL_ASPM)) {
			rtlpriv->intf_ops->enable_aspm(hw);
			RT_SET_PS_LEVEL(ppsc, RT_PS_LEVEL_ASPM);
		}
	}

	ppsc->swrf_processing = false;
}

void rtl_ips_nic_off_wq_callback(void *data)
{
	struct rtl_works *rtlworks =
	    container_of_dwork_rtl(data, struct rtl_works, ips_nic_off_wq);
	struct ieee80211_hw *hw = rtlworks->hw;
	struct rtl_priv *rtlpriv = rtl_priv(hw);
	struct rtl_hal *rtlhal = rtl_hal(rtl_priv(hw));
	struct rtl_mac *mac = rtl_mac(rtl_priv(hw));
	struct rtl_ps_ctl *ppsc = rtl_psc(rtl_priv(hw));
	enum rf_pwrstate rtstate;

	if (mac->opmode != NL80211_IFTYPE_STATION) {
		RT_TRACE(rtlpriv, COMP_ERR, DBG_WARNING,
			 "not station return\n");
		return;
	}

	if (mac->link_state > MAC80211_NOLINK)
		return;

	if (is_hal_stop(rtlhal))
		return;

	if (rtlpriv->sec.being_setkey)
		return;

	if (ppsc->inactiveps) {
		rtstate = ppsc->rfpwr_state;

		/*
		 *Do not enter IPS in the following conditions:
		 *(1) RF is already OFF or Sleep
		 *(2) swrf_processing (indicates the IPS is still under going)
		 *(3) Connectted (only disconnected can trigger IPS)
		 *(4) IBSS (send Beacon)
		 *(5) AP mode (send Beacon)
		 *(6) monitor mode (rcv packet)
		 */

		if (rtstate == ERFON &&
		    !ppsc->swrf_processing &&
		    (mac->link_state == MAC80211_NOLINK) &&
		    !mac->act_scanning) {
			RT_TRACE(rtlpriv, COMP_RF, DBG_TRACE,
				 "IPSEnter(): Turn off RF\n");

			ppsc->inactive_pwrstate = ERFOFF;
			ppsc->in_powersavemode = true;

			/*rtl_pci_reset_trx_ring(hw); */
			_rtl_ps_inactive_ps(hw);
		}
	}
}

void rtl_ips_nic_off(struct ieee80211_hw *hw)
{
	struct rtl_priv *rtlpriv = rtl_priv(hw);

	/*
	 *because when link with ap, mac80211 will ask us
	 *to disable nic quickly after scan before linking,
	 *this will cause link failed, so we delay 100ms here
	 */
	queue_delayed_work(rtlpriv->works.rtl_wq,
			   &rtlpriv->works.ips_nic_off_wq, MSECS(100));
}

void rtl_ips_nic_on(struct ieee80211_hw *hw)
{
	struct rtl_priv *rtlpriv = rtl_priv(hw);
	struct rtl_mac *mac = rtl_mac(rtl_priv(hw));
	struct rtl_ps_ctl *ppsc = rtl_psc(rtl_priv(hw));
	enum rf_pwrstate rtstate;
	unsigned long flags;

	if (mac->opmode != NL80211_IFTYPE_STATION)
		return;

	spin_lock_irqsave(&rtlpriv->locks.ips_lock, flags);

	if (ppsc->inactiveps) {
		rtstate = ppsc->rfpwr_state;

		if (rtstate != ERFON &&
		    !ppsc->swrf_processing &&
		    ppsc->rfoff_reason <= RF_CHANGE_BY_IPS) {

			ppsc->inactive_pwrstate = ERFON;
			ppsc->in_powersavemode = false;

			_rtl_ps_inactive_ps(hw);
		}
	}

	spin_unlock_irqrestore(&rtlpriv->locks.ips_lock, flags);
}

/*for FW LPS*/

/*
 *Determine if we can set Fw into PS mode
 *in current condition.Return TRUE if it
 *can enter PS mode.
 */
static bool rtl_get_fwlps_doze(struct ieee80211_hw *hw)
{
	struct rtl_priv *rtlpriv = rtl_priv(hw);
	struct rtl_mac *mac = rtl_mac(rtl_priv(hw));
	struct rtl_ps_ctl *ppsc = rtl_psc(rtl_priv(hw));
	u32 ps_timediff;

	ps_timediff = jiffies_to_msecs(jiffies -
				       ppsc->last_delaylps_stamp_jiffies);

	if (ps_timediff < 2000) {
		RT_TRACE(rtlpriv, COMP_POWER, DBG_LOUD,
			 "Delay enter Fw LPS for DHCP, ARP, or EAPOL exchanging state\n");
		return false;
	}

	if (mac->link_state != MAC80211_LINKED)
		return false;

	if (mac->opmode == NL80211_IFTYPE_ADHOC)
		return false;

	return true;
}

/* Change current and default preamble mode.*/
static void rtl_lps_set_psmode(struct ieee80211_hw *hw, u8 rt_psmode)
{
	struct rtl_priv *rtlpriv = rtl_priv(hw);
	struct rtl_mac *mac = rtl_mac(rtl_priv(hw));
	struct rtl_ps_ctl *ppsc = rtl_psc(rtl_priv(hw));
	u8 rpwm_val, fw_pwrmode;

	if (mac->opmode == NL80211_IFTYPE_ADHOC)
		return;

	if (mac->link_state != MAC80211_LINKED)
		return;

	if (ppsc->dot11_psmode == rt_psmode)
		return;

	/* Update power save mode configured. */
	ppsc->dot11_psmode = rt_psmode;

	/*
	 *<FW control LPS>
	 *1. Enter PS mode
	 *   Set RPWM to Fw to turn RF off and send H2C fw_pwrmode
	 *   cmd to set Fw into PS mode.
	 *2. Leave PS mode
	 *   Send H2C fw_pwrmode cmd to Fw to set Fw into Active
	 *   mode and set RPWM to turn RF on.
	 */

	if ((ppsc->fwctrl_lps) && ppsc->report_linked) {
		bool fw_current_inps;
		if (ppsc->dot11_psmode == EACTIVE) {
			RT_TRACE(rtlpriv, COMP_RF, DBG_DMESG,
				 "FW LPS leave ps_mode:%x\n",
				 FW_PS_ACTIVE_MODE);

			rpwm_val = 0x0C;	/* RF on */
			fw_pwrmode = FW_PS_ACTIVE_MODE;
			rtlpriv->cfg->ops->set_hw_reg(hw, HW_VAR_SET_RPWM,
					(u8 *) (&rpwm_val));
			rtlpriv->cfg->ops->set_hw_reg(hw,
					HW_VAR_H2C_FW_PWRMODE,
					(u8 *) (&fw_pwrmode));
			fw_current_inps = false;

			rtlpriv->cfg->ops->set_hw_reg(hw,
					HW_VAR_FW_PSMODE_STATUS,
					(u8 *) (&fw_current_inps));

		} else {
			if (rtl_get_fwlps_doze(hw)) {
				RT_TRACE(rtlpriv, COMP_RF, DBG_DMESG,
					 "FW LPS enter ps_mode:%x\n",
					 ppsc->fwctrl_psmode);

				rpwm_val = 0x02;	/* RF off */
				fw_current_inps = true;
				rtlpriv->cfg->ops->set_hw_reg(hw,
						HW_VAR_FW_PSMODE_STATUS,
						(u8 *) (&fw_current_inps));
				rtlpriv->cfg->ops->set_hw_reg(hw,
						HW_VAR_H2C_FW_PWRMODE,
						(u8 *) (&ppsc->fwctrl_psmode));

				rtlpriv->cfg->ops->set_hw_reg(hw,
						HW_VAR_SET_RPWM,
						(u8 *) (&rpwm_val));
			} else {
				/* Reset the power save related parameters. */
				ppsc->dot11_psmode = EACTIVE;
			}
		}
	}
}

/*Enter the leisure power save mode.*/
void rtl_lps_enter(struct ieee80211_hw *hw)
{
	struct rtl_mac *mac = rtl_mac(rtl_priv(hw));
	struct rtl_ps_ctl *ppsc = rtl_psc(rtl_priv(hw));
	struct rtl_priv *rtlpriv = rtl_priv(hw);

	if (!ppsc->fwctrl_lps)
		return;

	if (rtlpriv->sec.being_setkey)
		return;

	if (rtlpriv->link_info.busytraffic)
		return;

	/*sleep after linked 10s, to let DHCP and 4-way handshake ok enough!! */
	if (mac->cnt_after_linked < 5)
		return;

	if (mac->opmode == NL80211_IFTYPE_ADHOC)
		return;

	if (mac->link_state != MAC80211_LINKED)
		return;

	mutex_lock(&rtlpriv->locks.ps_mutex);

	/* Idle for a while if we connect to AP a while ago. */
	if (mac->cnt_after_linked >= 2) {
		if (ppsc->dot11_psmode == EACTIVE) {
			RT_TRACE(rtlpriv, COMP_POWER, DBG_LOUD,
				 "Enter 802.11 power save mode...\n");

			rtl_lps_set_psmode(hw, EAUTOPS);
		}
	}

	mutex_unlock(&rtlpriv->locks.ps_mutex);
}

/*Leave the leisure power save mode.*/
void rtl_lps_leave(struct ieee80211_hw *hw)
{
	struct rtl_priv *rtlpriv = rtl_priv(hw);
	struct rtl_ps_ctl *ppsc = rtl_psc(rtl_priv(hw));
	struct rtl_hal *rtlhal = rtl_hal(rtl_priv(hw));

	mutex_lock(&rtlpriv->locks.ps_mutex);

	if (ppsc->fwctrl_lps) {
		if (ppsc->dot11_psmode != EACTIVE) {

			/*FIX ME */
			rtlpriv->cfg->ops->enable_interrupt(hw);

			if (ppsc->reg_rfps_level & RT_RF_LPS_LEVEL_ASPM &&
			    RT_IN_PS_LEVEL(ppsc, RT_PS_LEVEL_ASPM) &&
			    rtlhal->interface == INTF_PCI) {
				rtlpriv->intf_ops->disable_aspm(hw);
				RT_CLEAR_PS_LEVEL(ppsc, RT_PS_LEVEL_ASPM);
			}

			RT_TRACE(rtlpriv, COMP_POWER, DBG_LOUD,
				 "Busy Traffic,Leave 802.11 power save..\n");

			rtl_lps_set_psmode(hw, EACTIVE);
		}
	}
	mutex_unlock(&rtlpriv->locks.ps_mutex);
}

/* For sw LPS*/
void rtl_swlps_beacon(struct ieee80211_hw *hw, void *data, unsigned int len)
{
	struct rtl_priv *rtlpriv = rtl_priv(hw);
	struct rtl_mac *mac = rtl_mac(rtl_priv(hw));
	struct ieee80211_hdr *hdr = (void *) data;
	struct ieee80211_tim_ie *tim_ie;
	u8 *tim;
	u8 tim_len;
	bool u_buffed;
	bool m_buffed;

	if (mac->opmode != NL80211_IFTYPE_STATION)
		return;

	if (!rtlpriv->psc.swctrl_lps)
		return;

	if (rtlpriv->mac80211.link_state != MAC80211_LINKED)
		return;

	if (!rtlpriv->psc.sw_ps_enabled)
		return;

	if (rtlpriv->psc.fwctrl_lps)
		return;

	if (likely(!(hw->conf.flags & IEEE80211_CONF_PS)))
		return;

	/* check if this really is a beacon */
	if (!ieee80211_is_beacon(hdr->frame_control))
		return;

	/* min. beacon length + FCS_LEN */
	if (len <= 40 + FCS_LEN)
		return;

	/* and only beacons from the associated BSSID, please */
	if (compare_ether_addr(hdr->addr3, rtlpriv->mac80211.bssid))
		return;

	rtlpriv->psc.last_beacon = jiffies;

	tim = rtl_find_ie(data, len - FCS_LEN, WLAN_EID_TIM);
	if (!tim)
		return;

	if (tim[1] < sizeof(*tim_ie))
		return;

	tim_len = tim[1];
	tim_ie = (struct ieee80211_tim_ie *) &tim[2];

	if (!WARN_ON_ONCE(!hw->conf.ps_dtim_period))
		rtlpriv->psc.dtim_counter = tim_ie->dtim_count;

	/* Check whenever the PHY can be turned off again. */

	/* 1. What about buffered unicast traffic for our AID? */
	u_buffed = ieee80211_check_tim(tim_ie, tim_len,
				       rtlpriv->mac80211.assoc_id);

	/* 2. Maybe the AP wants to send multicast/broadcast data? */
	m_buffed = tim_ie->bitmap_ctrl & 0x01;
	rtlpriv->psc.multi_buffered = m_buffed;

	/* unicast will process by mac80211 through
	 * set ~IEEE80211_CONF_PS, So we just check
	 * multicast frames here */
	if (!m_buffed) {
		/* back to low-power land. and delay is
		 * prevent null power save frame tx fail */
		queue_delayed_work(rtlpriv->works.rtl_wq,
				&rtlpriv->works.ps_work, MSECS(5));
	} else {
		RT_TRACE(rtlpriv, COMP_POWER, DBG_DMESG,
			 "u_bufferd: %x, m_buffered: %x\n", u_buffed, m_buffed);
	}
}

void rtl_swlps_rf_awake(struct ieee80211_hw *hw)
{
	struct rtl_priv *rtlpriv = rtl_priv(hw);
	struct rtl_ps_ctl *ppsc = rtl_psc(rtl_priv(hw));
	struct rtl_mac *mac = rtl_mac(rtl_priv(hw));

	if (!rtlpriv->psc.swctrl_lps)
		return;
	if (mac->link_state != MAC80211_LINKED)
		return;

	if (ppsc->reg_rfps_level & RT_RF_LPS_LEVEL_ASPM &&
		RT_IN_PS_LEVEL(ppsc, RT_PS_LEVEL_ASPM)) {
		rtlpriv->intf_ops->disable_aspm(hw);
		RT_CLEAR_PS_LEVEL(ppsc, RT_PS_LEVEL_ASPM);
	}

	mutex_lock(&rtlpriv->locks.ps_mutex);
	rtl_ps_set_rf_state(hw, ERFON, RF_CHANGE_BY_PS);
	mutex_unlock(&rtlpriv->locks.ps_mutex);
}

void rtl_swlps_rfon_wq_callback(void *data)
{
	struct rtl_works *rtlworks =
	    container_of_dwork_rtl(data, struct rtl_works, ps_rfon_wq);
	struct ieee80211_hw *hw = rtlworks->hw;

	rtl_swlps_rf_awake(hw);
}

void rtl_swlps_rf_sleep(struct ieee80211_hw *hw)
{
	struct rtl_priv *rtlpriv = rtl_priv(hw);
	struct rtl_mac *mac = rtl_mac(rtl_priv(hw));
	struct rtl_ps_ctl *ppsc = rtl_psc(rtl_priv(hw));
	u8 sleep_intv;

	if (!rtlpriv->psc.sw_ps_enabled)
		return;

	if ((rtlpriv->sec.being_setkey) ||
	    (mac->opmode == NL80211_IFTYPE_ADHOC))
		return;

	/*sleep after linked 10s, to let DHCP and 4-way handshake ok enough!! */
	if ((mac->link_state != MAC80211_LINKED) || (mac->cnt_after_linked < 5))
		return;

	if (rtlpriv->link_info.busytraffic)
		return;

	mutex_lock(&rtlpriv->locks.ps_mutex);
	rtl_ps_set_rf_state(hw, ERFSLEEP, RF_CHANGE_BY_PS);
	mutex_unlock(&rtlpriv->locks.ps_mutex);

	if (ppsc->reg_rfps_level & RT_RF_OFF_LEVL_ASPM &&
		!RT_IN_PS_LEVEL(ppsc, RT_PS_LEVEL_ASPM)) {
		rtlpriv->intf_ops->enable_aspm(hw);
		RT_SET_PS_LEVEL(ppsc, RT_PS_LEVEL_ASPM);
	}

	/* here is power save alg, when this beacon is DTIM
	 * we will set sleep time to dtim_period * n;
	 * when this beacon is not DTIM, we will set sleep
	 * time to sleep_intv = rtlpriv->psc.dtim_counter or
	 * MAX_SW_LPS_SLEEP_INTV(default set to 5) */

	if (rtlpriv->psc.dtim_counter == 0) {
		if (hw->conf.ps_dtim_period == 1)
			sleep_intv = hw->conf.ps_dtim_period * 2;
		else
			sleep_intv = hw->conf.ps_dtim_period;
	} else {
		sleep_intv = rtlpriv->psc.dtim_counter;
	}

	if (sleep_intv > MAX_SW_LPS_SLEEP_INTV)
		sleep_intv = MAX_SW_LPS_SLEEP_INTV;

	/* this print should always be dtim_conter = 0 &
	 * sleep  = dtim_period, that meaons, we should
	 * awake before every dtim */
	RT_TRACE(rtlpriv, COMP_POWER, DBG_DMESG,
		 "dtim_counter:%x will sleep :%d beacon_intv\n",
		 rtlpriv->psc.dtim_counter, sleep_intv);

	/* we tested that 40ms is enough for sw & hw sw delay */
	queue_delayed_work(rtlpriv->works.rtl_wq, &rtlpriv->works.ps_rfon_wq,
			MSECS(sleep_intv * mac->vif->bss_conf.beacon_int - 40));
}


void rtl_swlps_wq_callback(void *data)
{
	struct rtl_works *rtlworks = container_of_dwork_rtl(data,
				     struct rtl_works,
				     ps_work);
	struct ieee80211_hw *hw = rtlworks->hw;
	struct rtl_priv *rtlpriv = rtl_priv(hw);
	bool ps = false;

	ps = (hw->conf.flags & IEEE80211_CONF_PS);

	/* we can sleep after ps null send ok */
	if (rtlpriv->psc.state_inap) {
		rtl_swlps_rf_sleep(hw);

		if (rtlpriv->psc.state && !ps) {
			rtlpriv->psc.sleep_ms = jiffies_to_msecs(jiffies -
					rtlpriv->psc.last_action);
		}

		if (ps)
			rtlpriv->psc.last_slept = jiffies;

		rtlpriv->psc.last_action = jiffies;
		rtlpriv->psc.state = ps;
	}
}