1 files changed, 346 insertions, 0 deletions
diff --git a/drivers/staging/cw1200/pm.c b/drivers/staging/cw1200/pm.c
new file mode 100644
index 00000000000..7c1a957de3e
--- /dev/null
+++ b/drivers/staging/cw1200/pm.c
@@ -0,0 +1,346 @@
+/*
+ * Mac80211 power management API for ST-Ericsson CW1200 drivers
+ *
+ * Copyright (c) 2011, ST-Ericsson
+ * Author: Dmitry Tarnyagin <dmitry.tarnyagin@stericsson.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/platform_device.h>
+#include "cw1200.h"
+#include "pm.h"
+#include "sta.h"
+#include "bh.h"
+#include "sbus.h"
+
+static int cw1200_suspend_late(struct device *dev);
+static void cw1200_pm_release(struct device *dev);
+static int cw1200_pm_probe(struct platform_device *pdev);
+
+/* private */
+struct cw1200_suspend_state {
+	unsigned long bss_loss_tmo;
+	unsigned long connection_loss_tmo;
+	unsigned long join_tmo;
+	unsigned long direct_probe;
+	unsigned long link_id_gc;
+};
+
+static const struct dev_pm_ops cw1200_pm_ops = {
+	.suspend_noirq = cw1200_suspend_late,
+};
+
+static struct platform_driver cw1200_power_driver = {
+	.probe = cw1200_pm_probe,
+	.driver = {
+		.name = "cw1200_power",
+		.pm = &cw1200_pm_ops,
+	},
+};
+
+static int cw1200_pm_init_common(struct cw1200_pm_state *pm,
+				  struct cw1200_common *priv)
+{
+	int ret;
+
+	spin_lock_init(&pm->lock);
+	ret = platform_driver_register(&cw1200_power_driver);
+	if (ret)
+		return ret;
+	pm->pm_dev = platform_device_alloc("cw1200_power", 0);
+	if (!pm->pm_dev) {
+		platform_driver_unregister(&cw1200_power_driver);
+		return ENOMEM;
+	}
+
+	pm->pm_dev->dev.platform_data = priv;
+	ret = platform_device_add(pm->pm_dev);
+	if (ret) {
+		kfree(pm->pm_dev);
+		pm->pm_dev = NULL;
+	}
+
+	return ret;
+}
+
+static void cw1200_pm_deinit_common(struct cw1200_pm_state *pm)
+{
+	platform_driver_unregister(&cw1200_power_driver);
+	if (pm->pm_dev) {
+		pm->pm_dev->dev.platform_data = NULL;
+		platform_device_unregister(pm->pm_dev);
+		pm->pm_dev = NULL;
+	}
+}
+
+#ifdef CONFIG_WAKELOCK
+
+int cw1200_pm_init(struct cw1200_pm_state *pm,
+		   struct cw1200_common *priv)
+{
+	int ret = cw1200_pm_init_common(pm, priv);
+	if (!ret)
+		wake_lock_init(&pm->wakelock,
+			WAKE_LOCK_SUSPEND, "cw1200_wlan");
+	return ret;
+}
+
+void cw1200_pm_deinit(struct cw1200_pm_state *pm)
+{
+	if (wake_lock_active(&pm->wakelock))
+		wake_unlock(&pm->wakelock);
+	wake_lock_destroy(&pm->wakelock);
+	cw1200_pm_deinit_common(pm);
+}
+
+void cw1200_pm_stay_awake(struct cw1200_pm_state *pm,
+			  unsigned long tmo)
+{
+	long cur_tmo;
+	spin_lock_bh(&pm->lock);
+	cur_tmo = pm->wakelock.expires - jiffies;
+	if (!wake_lock_active(&pm->wakelock) ||
+			cur_tmo < (long)tmo)
+		wake_lock_timeout(&pm->wakelock, tmo);
+	spin_unlock_bh(&pm->lock);
+}
+
+#else /* CONFIG_WAKELOCK */
+
+static void cw1200_pm_stay_awake_tmo(unsigned long arg)
+{
+}
+
+int cw1200_pm_init(struct cw1200_pm_state *pm,
+		   struct cw1200_common *priv)
+{
+	int ret = cw1200_pm_init_common(pm, priv);
+	if (!ret) {
+		init_timer(&pm->stay_awake);
+		pm->stay_awake.data = (unsigned long)pm;
+		pm->stay_awake.function = cw1200_pm_stay_awake_tmo;
+	}
+	return ret;
+}
+
+void cw1200_pm_deinit(struct cw1200_pm_state *pm)
+{
+	del_timer_sync(&pm->stay_awake);
+	cw1200_pm_deinit_common(pm);
+}
+
+void cw1200_pm_stay_awake(struct cw1200_pm_state *pm,
+			  unsigned long tmo)
+{
+	long cur_tmo;
+	spin_lock_bh(&pm->lock);
+	cur_tmo = pm->stay_awake.expires - jiffies;
+	if (!timer_pending(&pm->stay_awake) ||
+			cur_tmo < (long)tmo)
+		mod_timer(&pm->stay_awake, jiffies + tmo);
+	spin_unlock_bh(&pm->lock);
+}
+
+#endif /* CONFIG_WAKELOCK */
+
+static long cw1200_suspend_work(struct delayed_work *work)
+{
+	int ret = cancel_delayed_work(work);
+	long tmo;
+	if (ret > 0) {
+		/* Timer is pending */
+		tmo = work->timer.expires - jiffies;
+		if (tmo < 0)
+			tmo = 0;
+	} else {
+		tmo = -1;
+	}
+	return tmo;
+}
+
+static int cw1200_resume_work(struct cw1200_common *priv,
+			       struct delayed_work *work,
+			       unsigned long tmo)
+{
+	if ((long)tmo < 0)
+		return 1;
+
+	return queue_delayed_work(priv->workqueue, work, tmo);
+}
+
+static int cw1200_suspend_late(struct device *dev)
+{
+	struct cw1200_common *priv = dev->platform_data;
+	if (atomic_read(&priv->bh_rx)) {
+		wiphy_dbg(priv->hw->wiphy,
+			"%s: Suspend interrupted.\n",
+			__func__);
+		return -EAGAIN;
+	}
+	return 0;
+}
+
+static void cw1200_pm_release(struct device *dev)
+{
+}
+
+static int cw1200_pm_probe(struct platform_device *pdev)
+{
+	pdev->dev.release = cw1200_pm_release;
+	return 0;
+}
+
+int cw1200_wow_suspend(struct ieee80211_hw *hw, struct cfg80211_wowlan *wowlan)
+{
+	struct cw1200_common *priv = hw->priv;
+	struct cw1200_pm_state *pm_state = &priv->pm_state;
+	struct cw1200_suspend_state *state;
+	int ret;
+
+#ifndef CONFIG_WAKELOCK
+	spin_lock_bh(&pm_state->lock);
+	ret = timer_pending(&pm_state->stay_awake);
+	spin_unlock_bh(&pm_state->lock);
+	if (ret)
+		return -EAGAIN;
+#endif
+
+	/* Do not suspend when datapath is not idle */
+	if (priv->tx_queue_stats.num_queued)
+		return -EBUSY;
+
+	/* Make sure there is no configuration requests in progress. */
+	if (!mutex_trylock(&priv->conf_mutex))
+		return -EBUSY;
+
+	/* Ensure pending operations are done.
+	 * Note also that wow_suspend must return in ~2.5sec, before
+	 * watchdog is triggered. */
+	if (priv->channel_switch_in_progress)
+		goto revert1;
+
+	/* Do not suspend when join work is scheduled */
+	if (work_pending(&priv->join_work))
+		goto revert1;
+
+	/* Do not suspend when scanning */
+	if (down_trylock(&priv->scan.lock))
+		goto revert1;
+
+	/* Lock TX. */
+	wsm_lock_tx_async(priv);
+	if (priv->hw_bufs_used)
+		goto revert3;
+
+	/* Allocate state */
+	state = kzalloc(sizeof(struct cw1200_suspend_state), GFP_KERNEL);
+	if (!state)
+		goto revert3;
+
+	/* Store delayed work states. */
+	state->bss_loss_tmo =
+		cw1200_suspend_work(&priv->bss_loss_work);
+	state->connection_loss_tmo =
+		cw1200_suspend_work(&priv->connection_loss_work);
+	state->join_tmo =
+		cw1200_suspend_work(&priv->join_timeout);
+	state->direct_probe =
+		cw1200_suspend_work(&priv->scan.probe_work);
+	state->link_id_gc =
+		cw1200_suspend_work(&priv->link_id_gc_work);
+
+	/* Stop serving thread */
+	if (cw1200_bh_suspend(priv))
+		goto revert4;
+
+	ret = timer_pending(&priv->mcast_timeout);
+	if (ret)
+		goto revert5;
+
+	/* Store suspend state */
+	pm_state->suspend_state = state;
+
+	/* Enable IRQ wake */
+	ret = priv->sbus_ops->power_mgmt(priv->sbus_priv, true);
+	if (ret) {
+		wiphy_err(priv->hw->wiphy,
+			"%s: PM request failed: %d. WoW is disabled.\n",
+			__func__, ret);
+		cw1200_wow_resume(hw);
+		return -EBUSY;
+	}
+
+	/* Force resume if event is coming from the device. */
+	if (atomic_read(&priv->bh_rx)) {
+		cw1200_wow_resume(hw);
+		return -EAGAIN;
+	}
+
+	return 0;
+
+revert5:
+	WARN_ON(cw1200_bh_resume(priv));
+revert4:
+	cw1200_resume_work(priv, &priv->bss_loss_work,
+			state->bss_loss_tmo);
+	cw1200_resume_work(priv, &priv->connection_loss_work,
+			state->connection_loss_tmo);
+	cw1200_resume_work(priv, &priv->join_timeout,
+			state->join_tmo);
+	cw1200_resume_work(priv, &priv->scan.probe_work,
+			state->direct_probe);
+	cw1200_resume_work(priv, &priv->link_id_gc_work,
+			state->link_id_gc);
+	kfree(state);
+revert3:
+	wsm_unlock_tx(priv);
+	up(&priv->scan.lock);
+revert1:
+	mutex_unlock(&priv->conf_mutex);
+	return -EBUSY;
+}
+
+int cw1200_wow_resume(struct ieee80211_hw *hw)
+{
+	struct cw1200_common *priv = hw->priv;
+	struct cw1200_pm_state *pm_state = &priv->pm_state;
+	struct cw1200_suspend_state *state;
+
+	state = pm_state->suspend_state;
+	pm_state->suspend_state = NULL;
+
+	/* Disable IRQ wake */
+	priv->sbus_ops->power_mgmt(priv->sbus_priv, false);
+
+	/* Resume BH thread */
+	WARN_ON(cw1200_bh_resume(priv));
+
+	/* Resume delayed work */
+	cw1200_resume_work(priv, &priv->bss_loss_work,
+			state->bss_loss_tmo);
+	cw1200_resume_work(priv, &priv->connection_loss_work,
+			state->connection_loss_tmo);
+	cw1200_resume_work(priv, &priv->join_timeout,
+			state->join_tmo);
+	cw1200_resume_work(priv, &priv->scan.probe_work,
+			state->direct_probe);
+	cw1200_resume_work(priv, &priv->link_id_gc_work,
+			state->link_id_gc);
+
+	/* Unlock datapath */
+	wsm_unlock_tx(priv);
+
+	/* Unlock scan */
+	up(&priv->scan.lock);
+
+	/* Unlock configuration mutex */
+	mutex_unlock(&priv->conf_mutex);
+
+	/* Free memory */
+	kfree(state);
+
+	return 0;
+}