[PATCH 2/4] ath9k: rework power state handling

[Felix Fietkau <nbd@openwrt.org>]

Turning off the radio when mac80211 tells the driver that it's idle is not
a good idea, as idle interfaces might still occasionally scan or send packets.
The only time the radio can be safely turned off is when drv_stop has been
called. In the mean time, use sc->ps_idle only to indicate network sleep vs
full sleep.
Move the LED GPIO changes out of the PCI suspend/resume path, the start/stop
functions already take care of that.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
---
 drivers/net/wireless/ath/ath9k/main.c |  156 ++++++++++-----------------------
 drivers/net/wireless/ath/ath9k/pci.c  |   19 +----
 2 files changed, 47 insertions(+), 128 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index 734e854..81e1368 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -883,82 +883,6 @@ chip_reset:
 #undef SCHED_INTR
 }
 
-static void ath_radio_enable(struct ath_softc *sc, struct ieee80211_hw *hw)
-{
-	struct ath_hw *ah = sc->sc_ah;
-	struct ath_common *common = ath9k_hw_common(ah);
-	struct ieee80211_channel *channel = hw->conf.channel;
-	int r;
-
-	ath9k_ps_wakeup(sc);
-	spin_lock_bh(&sc->sc_pcu_lock);
-	atomic_set(&ah->intr_ref_cnt, -1);
-
-	ath9k_hw_configpcipowersave(ah, false);
-
-	if (!ah->curchan)
-		ah->curchan = ath9k_cmn_get_curchannel(sc->hw, ah);
-
-	r = ath9k_hw_reset(ah, ah->curchan, ah->caldata, false);
-	if (r) {
-		ath_err(common,
-			"Unable to reset channel (%u MHz), reset status %d\n",
-			channel->center_freq, r);
-	}
-
-	ath_complete_reset(sc, true);
-
-	/* Enable LED */
-	ath9k_hw_cfg_output(ah, ah->led_pin,
-			    AR_GPIO_OUTPUT_MUX_AS_OUTPUT);
-	ath9k_hw_set_gpio(ah, ah->led_pin, 0);
-
-	spin_unlock_bh(&sc->sc_pcu_lock);
-
-	ath9k_ps_restore(sc);
-}
-
-void ath_radio_disable(struct ath_softc *sc, struct ieee80211_hw *hw)
-{
-	struct ath_hw *ah = sc->sc_ah;
-	struct ieee80211_channel *channel = hw->conf.channel;
-	int r;
-
-	ath9k_ps_wakeup(sc);
-
-	ath_cancel_work(sc);
-
-	spin_lock_bh(&sc->sc_pcu_lock);
-
-	/*
-	 * Keep the LED on when the radio is disabled
-	 * during idle unassociated state.
-	 */
-	if (!sc->ps_idle) {
-		ath9k_hw_set_gpio(ah, ah->led_pin, 1);
-		ath9k_hw_cfg_gpio_input(ah, ah->led_pin);
-	}
-
-	ath_prepare_reset(sc, false, true);
-
-	if (!ah->curchan)
-		ah->curchan = ath9k_cmn_get_curchannel(hw, ah);
-
-	r = ath9k_hw_reset(ah, ah->curchan, ah->caldata, false);
-	if (r) {
-		ath_err(ath9k_hw_common(sc->sc_ah),
-			"Unable to reset channel (%u MHz), reset status %d\n",
-			channel->center_freq, r);
-	}
-
-	ath9k_hw_phy_disable(ah);
-
-	ath9k_hw_configpcipowersave(ah, true);
-
-	spin_unlock_bh(&sc->sc_pcu_lock);
-	ath9k_ps_restore(sc);
-}
-
 static int ath_reset(struct ath_softc *sc, bool retry_tx)
 {
 	int r;
@@ -1094,6 +1018,9 @@ static int ath9k_start(struct ieee80211_hw *hw)
 	 * and then setup of the interrupt mask.
 	 */
 	spin_lock_bh(&sc->sc_pcu_lock);
+
+	atomic_set(&ah->intr_ref_cnt, -1);
+
 	r = ath9k_hw_reset(ah, init_channel, ah->caldata, false);
 	if (r) {
 		ath_err(common,
@@ -1132,6 +1059,18 @@ static int ath9k_start(struct ieee80211_hw *hw)
 		goto mutex_unlock;
 	}
 
+	if (ah->led_pin >= 0) {
+		ath9k_hw_cfg_output(ah, ah->led_pin,
+				    AR_GPIO_OUTPUT_MUX_AS_OUTPUT);
+		ath9k_hw_set_gpio(ah, ah->led_pin, 0);
+	}
+
+	/*
+	 * Reset key cache to sane defaults (all entries cleared) instead of
+	 * semi-random values after suspend/resume.
+	 */
+	ath9k_cmn_init_crypto(sc->sc_ah);
+
 	spin_unlock_bh(&sc->sc_pcu_lock);
 
 	if ((ah->btcoex_hw.scheme != ATH_BTCOEX_CFG_NONE) &&
@@ -1230,6 +1169,7 @@ static void ath9k_stop(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);
+	bool prev_idle;
 
 	mutex_lock(&sc->mutex);
 
@@ -1260,35 +1200,45 @@ static void ath9k_stop(struct ieee80211_hw *hw)
 	 * before setting the invalid flag. */
 	ath9k_hw_disable_interrupts(ah);
 
-	if (!(sc->sc_flags & SC_OP_INVALID)) {
-		ath_drain_all_txq(sc, false);
-		ath_stoprecv(sc);
-		ath9k_hw_phy_disable(ah);
-	} else
-		sc->rx.rxlink = NULL;
+	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);
+	tasklet_kill(&sc->bcon_tasklet);
+
+	prev_idle = sc->ps_idle;
+	sc->ps_idle = true;
+
+	spin_lock_bh(&sc->sc_pcu_lock);
+
+	if (ah->led_pin >= 0) {
+		ath9k_hw_set_gpio(ah, ah->led_pin, 1);
+		ath9k_hw_cfg_gpio_input(ah, ah->led_pin);
+	}
+
+	ath_prepare_reset(sc, false, true);
 
 	if (sc->rx.frag) {
 		dev_kfree_skb_any(sc->rx.frag);
 		sc->rx.frag = NULL;
 	}
 
-	/* disable HAL and put h/w to sleep */
-	ath9k_hw_disable(ah);
+	if (!ah->curchan)
+		ah->curchan = ath9k_cmn_get_curchannel(hw, ah);
 
-	spin_unlock_bh(&sc->sc_pcu_lock);
+	ath9k_hw_reset(ah, ah->curchan, ah->caldata, false);
+	ath9k_hw_phy_disable(ah);
 
-	/* 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);
-	tasklet_kill(&sc->bcon_tasklet);
+	ath9k_hw_configpcipowersave(ah, true);
 
-	ath9k_ps_restore(sc);
+	spin_unlock_bh(&sc->sc_pcu_lock);
 
-	sc->ps_idle = true;
-	ath_radio_disable(sc, hw);
+	ath9k_ps_restore(sc);
 
 	sc->sc_flags |= SC_OP_INVALID;
+	sc->ps_idle = prev_idle;
 
 	mutex_unlock(&sc->mutex);
 
@@ -1628,8 +1578,8 @@ static int ath9k_config(struct ieee80211_hw *hw, u32 changed)
 	struct ath_hw *ah = sc->sc_ah;
 	struct ath_common *common = ath9k_hw_common(ah);
 	struct ieee80211_conf *conf = &hw->conf;
-	bool disable_radio = false;
 
+	ath9k_ps_wakeup(sc);
 	mutex_lock(&sc->mutex);
 
 	/*
@@ -1638,16 +1588,8 @@ static int ath9k_config(struct ieee80211_hw *hw, u32 changed)
 	 * of the changes. Likewise we must only disable the radio towards
 	 * the end.
 	 */
-	if (changed & IEEE80211_CONF_CHANGE_IDLE) {
+	if (changed & IEEE80211_CONF_CHANGE_IDLE)
 		sc->ps_idle = !!(conf->flags & IEEE80211_CONF_IDLE);
-		if (!sc->ps_idle) {
-			ath_radio_enable(sc, hw);
-			ath_dbg(common, ATH_DBG_CONFIG,
-				"not-idle: enabling radio\n");
-		} else {
-			disable_radio = true;
-		}
-	}
 
 	/*
 	 * We just prepare to enable PS. We have to wait until our AP has
@@ -1753,18 +1695,12 @@ static int ath9k_config(struct ieee80211_hw *hw, u32 changed)
 		ath_dbg(common, ATH_DBG_CONFIG,
 			"Set power: %d\n", conf->power_level);
 		sc->config.txpowlimit = 2 * conf->power_level;
-		ath9k_ps_wakeup(sc);
 		ath9k_cmn_update_txpow(ah, sc->curtxpow,
 				       sc->config.txpowlimit, &sc->curtxpow);
-		ath9k_ps_restore(sc);
-	}
-
-	if (disable_radio) {
-		ath_dbg(common, ATH_DBG_CONFIG, "idle: disabling radio\n");
-		ath_radio_disable(sc, hw);
 	}
 
 	mutex_unlock(&sc->mutex);
+	ath9k_ps_restore(sc);
 
 	return 0;
 }
diff --git a/drivers/net/wireless/ath/ath9k/pci.c b/drivers/net/wireless/ath/ath9k/pci.c
index 2dcdf63..f42ab6c 100644
--- a/drivers/net/wireless/ath/ath9k/pci.c
+++ b/drivers/net/wireless/ath/ath9k/pci.c
@@ -307,12 +307,11 @@ static int ath_pci_suspend(struct device *device)
 	struct ieee80211_hw *hw = pci_get_drvdata(pdev);
 	struct ath_softc *sc = hw->priv;
 
-	ath9k_hw_set_gpio(sc->sc_ah, sc->sc_ah->led_pin, 1);
-
 	/* The device has to be moved to FULLSLEEP forcibly.
 	 * Otherwise the chip never moved to full sleep,
 	 * when no interface is up.
 	 */
+	ath9k_hw_disable(sc->sc_ah);
 	ath9k_hw_setpower(sc->sc_ah, ATH9K_PM_FULL_SLEEP);
 
 	return 0;
@@ -334,22 +333,6 @@ static int ath_pci_resume(struct device *device)
 	if ((val & 0x0000ff00) != 0)
 		pci_write_config_dword(pdev, 0x40, val & 0xffff00ff);
 
-	ath9k_ps_wakeup(sc);
-	/* Enable LED */
-	ath9k_hw_cfg_output(sc->sc_ah, sc->sc_ah->led_pin,
-			    AR_GPIO_OUTPUT_MUX_AS_OUTPUT);
-	ath9k_hw_set_gpio(sc->sc_ah, sc->sc_ah->led_pin, 0);
-
-	  /*
-	   * Reset key cache to sane defaults (all entries cleared) instead of
-	   * semi-random values after suspend/resume.
-	   */
-	ath9k_cmn_init_crypto(sc->sc_ah);
-	ath9k_ps_restore(sc);
-
-	sc->ps_idle = true;
-	ath_radio_disable(sc, hw);
-
 	return 0;
 }
 
-- 
1.7.3.2