1 files changed, 90 insertions, 15 deletions

diff --git a/drivers/acpi/wakeup.c b/drivers/acpi/wakeup.c
index 9614126bf56e..0b2e42530adf 100644
--- a/drivers/acpi/wakeup.c
+++ b/drivers/acpi/wakeup.c
@@ -12,6 +12,15 @@
 #include "internal.h"
 #include "sleep.h"
 
+struct acpi_wakeup_handler {
+	struct list_head list_node;
+	bool (*wakeup)(void *context);
+	void *context;
+};
+
+static LIST_HEAD(acpi_wakeup_handler_head);
+static DEFINE_MUTEX(acpi_wakeup_handler_mutex);
+
 /*
  * We didn't lock acpi_device_lock in the file, because it invokes oops in
  * suspend/resume and isn't really required as this is called in S-state. At
@@ -30,12 +39,10 @@ ACPI_MODULE_NAME("wakeup_devices")
  */
 void acpi_enable_wakeup_devices(u8 sleep_state)
 {
-	struct list_head *node, *next;
-
-	list_for_each_safe(node, next, &acpi_wakeup_device_list) {
-		struct acpi_device *dev =
-			container_of(node, struct acpi_device, wakeup_list);
+	struct acpi_device *dev, *tmp;
 
+	list_for_each_entry_safe(dev, tmp, &acpi_wakeup_device_list,
+				 wakeup_list) {
 		if (!dev->wakeup.flags.valid
 		    || sleep_state > (u32) dev->wakeup.sleep_state
 		    || !(device_may_wakeup(&dev->dev)
@@ -57,12 +64,10 @@ void acpi_enable_wakeup_devices(u8 sleep_state)
  */
 void acpi_disable_wakeup_devices(u8 sleep_state)
 {
-	struct list_head *node, *next;
-
-	list_for_each_safe(node, next, &acpi_wakeup_device_list) {
-		struct acpi_device *dev =
-			container_of(node, struct acpi_device, wakeup_list);
+	struct acpi_device *dev, *tmp;
 
+	list_for_each_entry_safe(dev, tmp, &acpi_wakeup_device_list,
+				 wakeup_list) {
 		if (!dev->wakeup.flags.valid
 		    || sleep_state > (u32) dev->wakeup.sleep_state
 		    || !(device_may_wakeup(&dev->dev)
@@ -79,13 +84,11 @@ void acpi_disable_wakeup_devices(u8 sleep_state)
 
 int __init acpi_wakeup_device_init(void)
 {
-	struct list_head *node, *next;
+	struct acpi_device *dev, *tmp;
 
 	mutex_lock(&acpi_device_lock);
-	list_for_each_safe(node, next, &acpi_wakeup_device_list) {
-		struct acpi_device *dev = container_of(node,
-						       struct acpi_device,
-						       wakeup_list);
+	list_for_each_entry_safe(dev, tmp, &acpi_wakeup_device_list,
+				 wakeup_list) {
 		if (device_can_wakeup(&dev->dev)) {
 			/* Button GPEs are supposed to be always enabled. */
 			acpi_enable_gpe(dev->wakeup.gpe_device,
@@ -96,3 +99,75 @@ int __init acpi_wakeup_device_init(void)
 	mutex_unlock(&acpi_device_lock);
 	return 0;
 }
+
+/**
+ * acpi_register_wakeup_handler - Register wakeup handler
+ * @wake_irq: The IRQ through which the device may receive wakeups
+ * @wakeup:   Wakeup-handler to call when the SCI has triggered a wakeup
+ * @context:  Context to pass to the handler when calling it
+ *
+ * Drivers which may share an IRQ with the SCI can use this to register
+ * a handler which returns true when the device they are managing wants
+ * to trigger a wakeup.
+ */
+int acpi_register_wakeup_handler(int wake_irq, bool (*wakeup)(void *context),
+				 void *context)
+{
+	struct acpi_wakeup_handler *handler;
+
+	/*
+	 * If the device is not sharing its IRQ with the SCI, there is no
+	 * need to register the handler.
+	 */
+	if (!acpi_sci_irq_valid() || wake_irq != acpi_sci_irq)
+		return 0;
+
+	handler = kmalloc(sizeof(*handler), GFP_KERNEL);
+	if (!handler)
+		return -ENOMEM;
+
+	handler->wakeup = wakeup;
+	handler->context = context;
+
+	mutex_lock(&acpi_wakeup_handler_mutex);
+	list_add(&handler->list_node, &acpi_wakeup_handler_head);
+	mutex_unlock(&acpi_wakeup_handler_mutex);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(acpi_register_wakeup_handler);
+
+/**
+ * acpi_unregister_wakeup_handler - Unregister wakeup handler
+ * @wakeup:   Wakeup-handler passed to acpi_register_wakeup_handler()
+ * @context:  Context passed to acpi_register_wakeup_handler()
+ */
+void acpi_unregister_wakeup_handler(bool (*wakeup)(void *context),
+				    void *context)
+{
+	struct acpi_wakeup_handler *handler;
+
+	mutex_lock(&acpi_wakeup_handler_mutex);
+	list_for_each_entry(handler, &acpi_wakeup_handler_head, list_node) {
+		if (handler->wakeup == wakeup && handler->context == context) {
+			list_del(&handler->list_node);
+			kfree(handler);
+			break;
+		}
+	}
+	mutex_unlock(&acpi_wakeup_handler_mutex);
+}
+EXPORT_SYMBOL_GPL(acpi_unregister_wakeup_handler);
+
+bool acpi_check_wakeup_handlers(void)
+{
+	struct acpi_wakeup_handler *handler;
+
+	/* No need to lock, nothing else is running when we're called. */
+	list_for_each_entry(handler, &acpi_wakeup_handler_head, list_node) {
+		if (handler->wakeup(handler->context))
+			return true;
+	}
+
+	return false;
+}