Merge branch 'pm-wakeirq'

* pm-wakeirq:
  PM / wakeirq: Fix typo in prototype for dev_pm_set_dedicated_wake_irq
  PM / Wakeirq: Add automated device wake IRQ handling

6 files changed, 422 insertions, 1 deletions

diff --git a/drivers/base/power/Makefile b/drivers/base/power/Makefile
index 1cb8544..f94a6cc 100644
--- a/drivers/base/power/Makefile
+++ b/drivers/base/power/Makefile
@@ -1,4 +1,4 @@
-obj-$(CONFIG_PM)	+= sysfs.o generic_ops.o common.o qos.o runtime.o
+obj-$(CONFIG_PM)	+= sysfs.o generic_ops.o common.o qos.o runtime.o wakeirq.o
 obj-$(CONFIG_PM_SLEEP)	+= main.o wakeup.o
 obj-$(CONFIG_PM_TRACE_RTC)	+= trace.o
 obj-$(CONFIG_PM_OPP)	+= opp.o
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index 5528e59..30b7bbf 100644
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -24,6 +24,7 @@
 #include <linux/pm.h>
 #include <linux/pm_runtime.h>
 #include <linux/pm-trace.h>
+#include <linux/pm_wakeirq.h>
 #include <linux/interrupt.h>
 #include <linux/sched.h>
 #include <linux/async.h>
@@ -587,6 +588,7 @@ void dpm_resume_noirq(pm_message_t state)
 	async_synchronize_full();
 	dpm_show_time(starttime, state, "noirq");
 	resume_device_irqs();
+	device_wakeup_disarm_wake_irqs();
 	cpuidle_resume();
 	trace_suspend_resume(TPS("dpm_resume_noirq"), state.event, false);
 }
@@ -1104,6 +1106,7 @@ int dpm_suspend_noirq(pm_message_t state)
 
 	trace_suspend_resume(TPS("dpm_suspend_noirq"), state.event, true);
 	cpuidle_pause();
+	device_wakeup_arm_wake_irqs();
 	suspend_device_irqs();
 	mutex_lock(&dpm_list_mtx);
 	pm_transition = state;
diff --git a/drivers/base/power/power.h b/drivers/base/power/power.h
index b6b8a27..f1a5d95 100644
--- a/drivers/base/power/power.h
+++ b/drivers/base/power/power.h
@@ -20,6 +20,46 @@ static inline void pm_runtime_early_init(struct device *dev)
 extern void pm_runtime_init(struct device *dev);
 extern void pm_runtime_remove(struct device *dev);
 
+struct wake_irq {
+	struct device *dev;
+	int irq;
+	bool dedicated_irq:1;
+};
+
+extern void dev_pm_arm_wake_irq(struct wake_irq *wirq);
+extern void dev_pm_disarm_wake_irq(struct wake_irq *wirq);
+
+#ifdef CONFIG_PM_SLEEP
+
+extern int device_wakeup_attach_irq(struct device *dev,
+				    struct wake_irq *wakeirq);
+extern void device_wakeup_detach_irq(struct device *dev);
+extern void device_wakeup_arm_wake_irqs(void);
+extern void device_wakeup_disarm_wake_irqs(void);
+
+#else
+
+static inline int
+device_wakeup_attach_irq(struct device *dev,
+			 struct wake_irq *wakeirq)
+{
+	return 0;
+}
+
+static inline void device_wakeup_detach_irq(struct device *dev)
+{
+}
+
+static inline void device_wakeup_arm_wake_irqs(void)
+{
+}
+
+static inline void device_wakeup_disarm_wake_irqs(void)
+{
+}
+
+#endif /* CONFIG_PM_SLEEP */
+
 /*
  * sysfs.c
  */
@@ -52,6 +92,14 @@ static inline void wakeup_sysfs_remove(struct device *dev) {}
 static inline int pm_qos_sysfs_add(struct device *dev) { return 0; }
 static inline void pm_qos_sysfs_remove(struct device *dev) {}
 
+static inline void dev_pm_arm_wake_irq(struct wake_irq *wirq)
+{
+}
+
+static inline void dev_pm_disarm_wake_irq(struct wake_irq *wirq)
+{
+}
+
 #endif
 
 #ifdef CONFIG_PM_SLEEP
diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c
index 4ffe4a2..e1a10a0 100644
--- a/drivers/base/power/runtime.c
+++ b/drivers/base/power/runtime.c
@@ -10,6 +10,7 @@
 #include <linux/sched.h>
 #include <linux/export.h>
 #include <linux/pm_runtime.h>
+#include <linux/pm_wakeirq.h>
 #include <trace/events/rpm.h>
 #include "power.h"
 
@@ -514,6 +515,7 @@ static int rpm_suspend(struct device *dev, int rpmflags)
 
 	callback = RPM_GET_CALLBACK(dev, runtime_suspend);
 
+	dev_pm_enable_wake_irq(dev);
 	retval = rpm_callback(callback, dev);
 	if (retval)
 		goto fail;
@@ -552,6 +554,7 @@ static int rpm_suspend(struct device *dev, int rpmflags)
 	return retval;
 
  fail:
+	dev_pm_disable_wake_irq(dev);
 	__update_runtime_status(dev, RPM_ACTIVE);
 	dev->power.deferred_resume = false;
 	wake_up_all(&dev->power.wait_queue);
@@ -734,10 +737,12 @@ static int rpm_resume(struct device *dev, int rpmflags)
 
 	callback = RPM_GET_CALLBACK(dev, runtime_resume);
 
+	dev_pm_disable_wake_irq(dev);
 	retval = rpm_callback(callback, dev);
 	if (retval) {
 		__update_runtime_status(dev, RPM_SUSPENDED);
 		pm_runtime_cancel_pending(dev);
+		dev_pm_enable_wake_irq(dev);
 	} else {
  no_callback:
 		__update_runtime_status(dev, RPM_ACTIVE);
diff --git a/drivers/base/power/wakeirq.c b/drivers/base/power/wakeirq.c
new file mode 100644
index 0000000..7470004
--- /dev/null
+++ b/drivers/base/power/wakeirq.c
@@ -0,0 +1,273 @@
+/*
+ * wakeirq.c - Device wakeirq helper functions
+ *
+ * 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.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/slab.h>
+#include <linux/pm_runtime.h>
+#include <linux/pm_wakeirq.h>
+
+#include "power.h"
+
+/**
+ * dev_pm_attach_wake_irq - Attach device interrupt as a wake IRQ
+ * @dev: Device entry
+ * @irq: Device wake-up capable interrupt
+ * @wirq: Wake irq specific data
+ *
+ * Internal function to attach either a device IO interrupt or a
+ * dedicated wake-up interrupt as a wake IRQ.
+ */
+static int dev_pm_attach_wake_irq(struct device *dev, int irq,
+				  struct wake_irq *wirq)
+{
+	unsigned long flags;
+	int err;
+
+	if (!dev || !wirq)
+		return -EINVAL;
+
+	spin_lock_irqsave(&dev->power.lock, flags);
+	if (dev_WARN_ONCE(dev, dev->power.wakeirq,
+			  "wake irq already initialized\n")) {
+		spin_unlock_irqrestore(&dev->power.lock, flags);
+		return -EEXIST;
+	}
+
+	dev->power.wakeirq = wirq;
+	spin_unlock_irqrestore(&dev->power.lock, flags);
+
+	err = device_wakeup_attach_irq(dev, wirq);
+	if (err)
+		return err;
+
+	return 0;
+}
+
+/**
+ * dev_pm_set_wake_irq - Attach device IO interrupt as wake IRQ
+ * @dev: Device entry
+ * @irq: Device IO interrupt
+ *
+ * Attach a device IO interrupt as a wake IRQ. The wake IRQ gets
+ * automatically configured for wake-up from suspend  based
+ * on the device specific sysfs wakeup entry. Typically called
+ * during driver probe after calling device_init_wakeup().
+ */
+int dev_pm_set_wake_irq(struct device *dev, int irq)
+{
+	struct wake_irq *wirq;
+	int err;
+
+	wirq = kzalloc(sizeof(*wirq), GFP_KERNEL);
+	if (!wirq)
+		return -ENOMEM;
+
+	wirq->dev = dev;
+	wirq->irq = irq;
+
+	err = dev_pm_attach_wake_irq(dev, irq, wirq);
+	if (err)
+		kfree(wirq);
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(dev_pm_set_wake_irq);
+
+/**
+ * dev_pm_clear_wake_irq - Detach a device IO interrupt wake IRQ
+ * @dev: Device entry
+ *
+ * Detach a device wake IRQ and free resources.
+ *
+ * Note that it's OK for drivers to call this without calling
+ * dev_pm_set_wake_irq() as all the driver instances may not have
+ * a wake IRQ configured. This avoid adding wake IRQ specific
+ * checks into the drivers.
+ */
+void dev_pm_clear_wake_irq(struct device *dev)
+{
+	struct wake_irq *wirq = dev->power.wakeirq;
+	unsigned long flags;
+
+	if (!wirq)
+		return;
+
+	spin_lock_irqsave(&dev->power.lock, flags);
+	dev->power.wakeirq = NULL;
+	spin_unlock_irqrestore(&dev->power.lock, flags);
+
+	device_wakeup_detach_irq(dev);
+	if (wirq->dedicated_irq)
+		free_irq(wirq->irq, wirq);
+	kfree(wirq);
+}
+EXPORT_SYMBOL_GPL(dev_pm_clear_wake_irq);
+
+/**
+ * handle_threaded_wake_irq - Handler for dedicated wake-up interrupts
+ * @irq: Device specific dedicated wake-up interrupt
+ * @_wirq: Wake IRQ data
+ *
+ * Some devices have a separate wake-up interrupt in addition to the
+ * device IO interrupt. The wake-up interrupt signals that a device
+ * should be woken up from it's idle state. This handler uses device
+ * specific pm_runtime functions to wake the device, and then it's
+ * up to the device to do whatever it needs to. Note that as the
+ * device may need to restore context and start up regulators, we
+ * use a threaded IRQ.
+ *
+ * Also note that we are not resending the lost device interrupts.
+ * We assume that the wake-up interrupt just needs to wake-up the
+ * device, and then device's pm_runtime_resume() can deal with the
+ * situation.
+ */
+static irqreturn_t handle_threaded_wake_irq(int irq, void *_wirq)
+{
+	struct wake_irq *wirq = _wirq;
+	int res;
+
+	/* We don't want RPM_ASYNC or RPM_NOWAIT here */
+	res = pm_runtime_resume(wirq->dev);
+	if (res < 0)
+		dev_warn(wirq->dev,
+			 "wake IRQ with no resume: %i\n", res);
+
+	return IRQ_HANDLED;
+}
+
+/**
+ * dev_pm_set_dedicated_wake_irq - Request a dedicated wake-up interrupt
+ * @dev: Device entry
+ * @irq: Device wake-up interrupt
+ *
+ * Unless your hardware has separate wake-up interrupts in addition
+ * to the device IO interrupts, you don't need this.
+ *
+ * Sets up a threaded interrupt handler for a device that has
+ * a dedicated wake-up interrupt in addition to the device IO
+ * interrupt.
+ *
+ * The interrupt starts disabled, and needs to be managed for
+ * the device by the bus code or the device driver using
+ * dev_pm_enable_wake_irq() and dev_pm_disable_wake_irq()
+ * functions.
+ */
+int dev_pm_set_dedicated_wake_irq(struct device *dev, int irq)
+{
+	struct wake_irq *wirq;
+	int err;
+
+	wirq = kzalloc(sizeof(*wirq), GFP_KERNEL);
+	if (!wirq)
+		return -ENOMEM;
+
+	wirq->dev = dev;
+	wirq->irq = irq;
+	wirq->dedicated_irq = true;
+	irq_set_status_flags(irq, IRQ_NOAUTOEN);
+
+	/*
+	 * Consumer device may need to power up and restore state
+	 * so we use a threaded irq.
+	 */
+	err = request_threaded_irq(irq, NULL, handle_threaded_wake_irq,
+				   IRQF_ONESHOT, dev_name(dev), wirq);
+	if (err)
+		goto err_free;
+
+	err = dev_pm_attach_wake_irq(dev, irq, wirq);
+	if (err)
+		goto err_free_irq;
+
+	return err;
+
+err_free_irq:
+	free_irq(irq, wirq);
+err_free:
+	kfree(wirq);
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(dev_pm_set_dedicated_wake_irq);
+
+/**
+ * dev_pm_enable_wake_irq - Enable device wake-up interrupt
+ * @dev: Device
+ *
+ * Called from the bus code or the device driver for
+ * runtime_suspend() to enable the wake-up interrupt while
+ * the device is running.
+ *
+ * Note that for runtime_suspend()) the wake-up interrupts
+ * should be unconditionally enabled unlike for suspend()
+ * that is conditional.
+ */
+void dev_pm_enable_wake_irq(struct device *dev)
+{
+	struct wake_irq *wirq = dev->power.wakeirq;
+
+	if (wirq && wirq->dedicated_irq)
+		enable_irq(wirq->irq);
+}
+EXPORT_SYMBOL_GPL(dev_pm_enable_wake_irq);
+
+/**
+ * dev_pm_disable_wake_irq - Disable device wake-up interrupt
+ * @dev: Device
+ *
+ * Called from the bus code or the device driver for
+ * runtime_resume() to disable the wake-up interrupt while
+ * the device is running.
+ */
+void dev_pm_disable_wake_irq(struct device *dev)
+{
+	struct wake_irq *wirq = dev->power.wakeirq;
+
+	if (wirq && wirq->dedicated_irq)
+		disable_irq_nosync(wirq->irq);
+}
+EXPORT_SYMBOL_GPL(dev_pm_disable_wake_irq);
+
+/**
+ * dev_pm_arm_wake_irq - Arm device wake-up
+ * @wirq: Device wake-up interrupt
+ *
+ * Sets up the wake-up event conditionally based on the
+ * device_may_wake().
+ */
+void dev_pm_arm_wake_irq(struct wake_irq *wirq)
+{
+	if (!wirq)
+		return;
+
+	if (device_may_wakeup(wirq->dev))
+		enable_irq_wake(wirq->irq);
+}
+
+/**
+ * dev_pm_disarm_wake_irq - Disarm device wake-up
+ * @wirq: Device wake-up interrupt
+ *
+ * Clears up the wake-up event conditionally based on the
+ * device_may_wake().
+ */
+void dev_pm_disarm_wake_irq(struct wake_irq *wirq)
+{
+	if (!wirq)
+		return;
+
+	if (device_may_wakeup(wirq->dev))
+		disable_irq_wake(wirq->irq);
+}
diff --git a/drivers/base/power/wakeup.c b/drivers/base/power/wakeup.c
index 87c2603..40f7160 100644
--- a/drivers/base/power/wakeup.c
+++ b/drivers/base/power/wakeup.c
@@ -14,6 +14,7 @@
 #include <linux/suspend.h>
 #include <linux/seq_file.h>
 #include <linux/debugfs.h>
+#include <linux/pm_wakeirq.h>
 #include <trace/events/power.h>
 
 #include "power.h"
@@ -273,6 +274,97 @@ int device_wakeup_enable(struct device *dev)
 EXPORT_SYMBOL_GPL(device_wakeup_enable);
 
 /**
+ * device_wakeup_attach_irq - Attach a wakeirq to a wakeup source
+ * @dev: Device to handle
+ * @wakeirq: Device specific wakeirq entry
+ *
+ * Attach a device wakeirq to the wakeup source so the device
+ * wake IRQ can be configured automatically for suspend and
+ * resume.
+ */
+int device_wakeup_attach_irq(struct device *dev,
+			     struct wake_irq *wakeirq)
+{
+	struct wakeup_source *ws;
+	int ret = 0;
+
+	spin_lock_irq(&dev->power.lock);
+	ws = dev->power.wakeup;
+	if (!ws) {
+		dev_err(dev, "forgot to call call device_init_wakeup?\n");
+		ret = -EINVAL;
+		goto unlock;
+	}
+
+	if (ws->wakeirq) {
+		ret = -EEXIST;
+		goto unlock;
+	}
+
+	ws->wakeirq = wakeirq;
+
+unlock:
+	spin_unlock_irq(&dev->power.lock);
+
+	return ret;
+}
+
+/**
+ * device_wakeup_detach_irq - Detach a wakeirq from a wakeup source
+ * @dev: Device to handle
+ *
+ * Removes a device wakeirq from the wakeup source.
+ */
+void device_wakeup_detach_irq(struct device *dev)
+{
+	struct wakeup_source *ws;
+
+	spin_lock_irq(&dev->power.lock);
+	ws = dev->power.wakeup;
+	if (!ws)
+		goto unlock;
+
+	ws->wakeirq = NULL;
+
+unlock:
+	spin_unlock_irq(&dev->power.lock);
+}
+
+/**
+ * device_wakeup_arm_wake_irqs(void)
+ *
+ * Itereates over the list of device wakeirqs to arm them.
+ */
+void device_wakeup_arm_wake_irqs(void)
+{
+	struct wakeup_source *ws;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(ws, &wakeup_sources, entry) {
+		if (ws->wakeirq)
+			dev_pm_arm_wake_irq(ws->wakeirq);
+	}
+	rcu_read_unlock();
+}
+
+/**
+ * device_wakeup_disarm_wake_irqs(void)
+ *
+ * Itereates over the list of device wakeirqs to disarm them.
+ */
+void device_wakeup_disarm_wake_irqs(void)
+{
+	struct wakeup_source *ws;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(ws, &wakeup_sources, entry) {
+		if (ws->wakeirq)
+			dev_pm_disarm_wake_irq(ws->wakeirq);
+	}
+	rcu_read_unlock();
+}
+
+/**
  * device_wakeup_detach - Detach a device's wakeup source object from it.
  * @dev: Device to detach the wakeup source object from.
  *