1 files changed, 319 insertions, 0 deletions
diff --git a/drivers/usb/host/dwc_common_port/dwc_notifier.c b/drivers/usb/host/dwc_common_port/dwc_notifier.c
new file mode 100644
index 000000000000..8b3772afe11d
--- /dev/null
+++ b/drivers/usb/host/dwc_common_port/dwc_notifier.c
@@ -0,0 +1,319 @@
+#ifdef DWC_NOTIFYLIB
+
+#include "dwc_notifier.h"
+#include "dwc_list.h"
+
+typedef struct dwc_observer {
+	void *observer;
+	dwc_notifier_callback_t callback;
+	void *data;
+	char *notification;
+	DWC_CIRCLEQ_ENTRY(dwc_observer) list_entry;
+} observer_t;
+
+DWC_CIRCLEQ_HEAD(observer_queue, dwc_observer);
+
+typedef struct dwc_notifier {
+	void *mem_ctx;
+	void *object;
+	struct observer_queue observers;
+	DWC_CIRCLEQ_ENTRY(dwc_notifier) list_entry;
+} notifier_t;
+
+DWC_CIRCLEQ_HEAD(notifier_queue, dwc_notifier);
+
+typedef struct manager {
+	void *mem_ctx;
+	void *wkq_ctx;
+	dwc_workq_t *wq;
+//	dwc_mutex_t *mutex;
+	struct notifier_queue notifiers;
+} manager_t;
+
+static manager_t *manager = NULL;
+
+static int create_manager(void *mem_ctx, void *wkq_ctx)
+{
+	manager = dwc_alloc(mem_ctx, sizeof(manager_t));
+	if (!manager) {
+		return -DWC_E_NO_MEMORY;
+	}
+
+	DWC_CIRCLEQ_INIT(&manager->notifiers);
+
+	manager->wq = dwc_workq_alloc(wkq_ctx, "DWC Notification WorkQ");
+	if (!manager->wq) {
+		return -DWC_E_NO_MEMORY;
+	}
+
+	return 0;
+}
+
+static void free_manager(void)
+{
+	dwc_workq_free(manager->wq);
+
+	/* All notifiers must have unregistered themselves before this module
+	 * can be removed.  Hitting this assertion indicates a programmer
+	 * error. */
+	DWC_ASSERT(DWC_CIRCLEQ_EMPTY(&manager->notifiers),
+		   "Notification manager being freed before all notifiers have been removed");
+	dwc_free(manager->mem_ctx, manager);
+}
+
+#ifdef DEBUG
+static void dump_manager(void)
+{
+	notifier_t *n;
+	observer_t *o;
+
+	DWC_ASSERT(manager, "Notification manager not found");
+
+	DWC_DEBUG("List of all notifiers and observers:\n");
+	DWC_CIRCLEQ_FOREACH(n, &manager->notifiers, list_entry) {
+		DWC_DEBUG("Notifier %p has observers:\n", n->object);
+		DWC_CIRCLEQ_FOREACH(o, &n->observers, list_entry) {
+			DWC_DEBUG("    %p watching %s\n", o->observer, o->notification);
+		}
+	}
+}
+#else
+#define dump_manager(...)
+#endif
+
+static observer_t *alloc_observer(void *mem_ctx, void *observer, char *notification,
+				  dwc_notifier_callback_t callback, void *data)
+{
+	observer_t *new_observer = dwc_alloc(mem_ctx, sizeof(observer_t));
+
+	if (!new_observer) {
+		return NULL;
+	}
+
+	DWC_CIRCLEQ_INIT_ENTRY(new_observer, list_entry);
+	new_observer->observer = observer;
+	new_observer->notification = notification;
+	new_observer->callback = callback;
+	new_observer->data = data;
+	return new_observer;
+}
+
+static void free_observer(void *mem_ctx, observer_t *observer)
+{
+	dwc_free(mem_ctx, observer);
+}
+
+static notifier_t *alloc_notifier(void *mem_ctx, void *object)
+{
+	notifier_t *notifier;
+
+	if (!object) {
+		return NULL;
+	}
+
+	notifier = dwc_alloc(mem_ctx, sizeof(notifier_t));
+	if (!notifier) {
+		return NULL;
+	}
+
+	DWC_CIRCLEQ_INIT(&notifier->observers);
+	DWC_CIRCLEQ_INIT_ENTRY(notifier, list_entry);
+
+	notifier->mem_ctx = mem_ctx;
+	notifier->object = object;
+	return notifier;
+}
+
+static void free_notifier(notifier_t *notifier)
+{
+	observer_t *observer;
+
+	DWC_CIRCLEQ_FOREACH(observer, &notifier->observers, list_entry) {
+		free_observer(notifier->mem_ctx, observer);
+	}
+
+	dwc_free(notifier->mem_ctx, notifier);
+}
+
+static notifier_t *find_notifier(void *object)
+{
+	notifier_t *notifier;
+
+	DWC_ASSERT(manager, "Notification manager not found");
+
+	if (!object) {
+		return NULL;
+	}
+
+	DWC_CIRCLEQ_FOREACH(notifier, &manager->notifiers, list_entry) {
+		if (notifier->object == object) {
+			return notifier;
+		}
+	}
+
+	return NULL;
+}
+
+int dwc_alloc_notification_manager(void *mem_ctx, void *wkq_ctx)
+{
+	return create_manager(mem_ctx, wkq_ctx);
+}
+
+void dwc_free_notification_manager(void)
+{
+	free_manager();
+}
+
+dwc_notifier_t *dwc_register_notifier(void *mem_ctx, void *object)
+{
+	notifier_t *notifier;
+
+	DWC_ASSERT(manager, "Notification manager not found");
+
+	notifier = find_notifier(object);
+	if (notifier) {
+		DWC_ERROR("Notifier %p is already registered\n", object);
+		return NULL;
+	}
+
+	notifier = alloc_notifier(mem_ctx, object);
+	if (!notifier) {
+		return NULL;
+	}
+
+	DWC_CIRCLEQ_INSERT_TAIL(&manager->notifiers, notifier, list_entry);
+
+	DWC_INFO("Notifier %p registered", object);
+	dump_manager();
+
+	return notifier;
+}
+
+void dwc_unregister_notifier(dwc_notifier_t *notifier)
+{
+	DWC_ASSERT(manager, "Notification manager not found");
+
+	if (!DWC_CIRCLEQ_EMPTY(&notifier->observers)) {
+		observer_t *o;
+
+		DWC_ERROR("Notifier %p has active observers when removing\n", notifier->object);
+		DWC_CIRCLEQ_FOREACH(o, &notifier->observers, list_entry) {
+			DWC_DEBUGC("    %p watching %s\n", o->observer, o->notification);
+		}
+
+		DWC_ASSERT(DWC_CIRCLEQ_EMPTY(&notifier->observers),
+			   "Notifier %p has active observers when removing", notifier);
+	}
+
+	DWC_CIRCLEQ_REMOVE_INIT(&manager->notifiers, notifier, list_entry);
+	free_notifier(notifier);
+
+	DWC_INFO("Notifier unregistered");
+	dump_manager();
+}
+
+/* Add an observer to observe the notifier for a particular state, event, or notification. */
+int dwc_add_observer(void *observer, void *object, char *notification,
+		     dwc_notifier_callback_t callback, void *data)
+{
+	notifier_t *notifier = find_notifier(object);
+	observer_t *new_observer;
+
+	if (!notifier) {
+		DWC_ERROR("Notifier %p is not found when adding observer\n", object);
+		return -DWC_E_INVALID;
+	}
+
+	new_observer = alloc_observer(notifier->mem_ctx, observer, notification, callback, data);
+	if (!new_observer) {
+		return -DWC_E_NO_MEMORY;
+	}
+
+	DWC_CIRCLEQ_INSERT_TAIL(&notifier->observers, new_observer, list_entry);
+
+	DWC_INFO("Added observer %p to notifier %p observing notification %s, callback=%p, data=%p",
+		 observer, object, notification, callback, data);
+
+	dump_manager();
+	return 0;
+}
+
+int dwc_remove_observer(void *observer)
+{
+	notifier_t *n;
+
+	DWC_ASSERT(manager, "Notification manager not found");
+
+	DWC_CIRCLEQ_FOREACH(n, &manager->notifiers, list_entry) {
+		observer_t *o;
+		observer_t *o2;
+
+		DWC_CIRCLEQ_FOREACH_SAFE(o, o2, &n->observers, list_entry) {
+			if (o->observer == observer) {
+				DWC_CIRCLEQ_REMOVE_INIT(&n->observers, o, list_entry);
+				DWC_INFO("Removing observer %p from notifier %p watching notification %s:",
+					 o->observer, n->object, o->notification);
+				free_observer(n->mem_ctx, o);
+			}
+		}
+	}
+
+	dump_manager();
+	return 0;
+}
+
+typedef struct callback_data {
+	void *mem_ctx;
+	dwc_notifier_callback_t cb;
+	void *observer;
+	void *data;
+	void *object;
+	char *notification;
+	void *notification_data;
+} cb_data_t;
+
+static void cb_task(void *data)
+{
+	cb_data_t *cb = (cb_data_t *)data;
+
+	cb->cb(cb->object, cb->notification, cb->observer, cb->notification_data, cb->data);
+	dwc_free(cb->mem_ctx, cb);
+}
+
+void dwc_notify(dwc_notifier_t *notifier, char *notification, void *notification_data)
+{
+	observer_t *o;
+
+	DWC_ASSERT(manager, "Notification manager not found");
+
+	DWC_CIRCLEQ_FOREACH(o, &notifier->observers, list_entry) {
+		int len = DWC_STRLEN(notification);
+
+		if (DWC_STRLEN(o->notification) != len) {
+			continue;
+		}
+
+		if (DWC_STRNCMP(o->notification, notification, len) == 0) {
+			cb_data_t *cb_data = dwc_alloc(notifier->mem_ctx, sizeof(cb_data_t));
+
+			if (!cb_data) {
+				DWC_ERROR("Failed to allocate callback data\n");
+				return;
+			}
+
+			cb_data->mem_ctx = notifier->mem_ctx;
+			cb_data->cb = o->callback;
+			cb_data->observer = o->observer;
+			cb_data->data = o->data;
+			cb_data->object = notifier->object;
+			cb_data->notification = notification;
+			cb_data->notification_data = notification_data;
+			DWC_DEBUGC("Observer found %p for notification %s\n", o->observer, notification);
+			DWC_WORKQ_SCHEDULE(manager->wq, cb_task, cb_data,
+					   "Notify callback from %p for Notification %s, to observer %p",
+					   cb_data->object, notification, cb_data->observer);
+		}
+	}
+}
+
+#endif	/* DWC_NOTIFYLIB */