3 files changed, 306 insertions, 0 deletions

diff --git a/drivers/video/display/Kconfig b/drivers/video/display/Kconfig
new file mode 100644
index 00000000000..477192d69af
--- /dev/null
+++ b/drivers/video/display/Kconfig
@@ -0,0 +1,10 @@
+menuconfig DISPLAY_CORE
+	tristate "Display Core"
+	---help---
+	  Support common display framework for graphics devices.
+
+if DISPLAY_CORE
+
+
+
+endif # DISPLAY_CORE
diff --git a/drivers/video/display/Makefile b/drivers/video/display/Makefile
new file mode 100644
index 00000000000..bd93496d2cf
--- /dev/null
+++ b/drivers/video/display/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_DISPLAY_CORE) += display-core.o
diff --git a/drivers/video/display/display-core.c b/drivers/video/display/display-core.c
new file mode 100644
index 00000000000..9c93aae3926
--- /dev/null
+++ b/drivers/video/display/display-core.c
@@ -0,0 +1,295 @@
+/*
+ * Display Core
+ *
+ * Copyright (C) 2012 Renesas Solutions Corp.
+ *
+ * Contacts: Laurent Pinchart <laurent.pinchart@ideasonboard.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/export.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+
+#include <video/display.h>
+#include <video/videomode.h>
+
+static struct video_source *video_source_bind(struct display_entity *entity);
+static void video_source_unbind(struct display_entity *entity);
+
+/* -----------------------------------------------------------------------------
+ * Display Entity
+ */
+
+static LIST_HEAD(display_entity_list);
+static DEFINE_MUTEX(display_entity_mutex);
+
+struct display_entity *display_entity_get_first(void)
+{
+	/* FIXME: Don't we need some locking here? */
+
+	if (list_empty(&display_entity_list))
+		return NULL;
+
+	return list_first_entry(&display_entity_list, struct display_entity,
+			list);
+}
+EXPORT_SYMBOL(display_entity_get_first);
+
+int display_entity_set_state(struct display_entity *entity,
+			     enum display_entity_state state)
+{
+	int ret;
+
+	if (entity->state == state)
+		return 0;
+
+	if (!entity->ops || !entity->ops->set_state)
+		return 0;
+
+	ret = entity->ops->set_state(entity, state);
+	if (ret < 0)
+		return ret;
+
+	entity->state = state;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(display_entity_set_state);
+
+int display_entity_get_modes(struct display_entity *entity,
+			     const struct videomode **modes)
+{
+	if (!entity->ops || !entity->ops->get_modes)
+		return 0;
+
+	return entity->ops->get_modes(entity, modes);
+}
+EXPORT_SYMBOL_GPL(display_entity_get_modes);
+
+int display_entity_get_size(struct display_entity *entity,
+			    unsigned int *width, unsigned int *height)
+{
+	if (!entity->ops || !entity->ops->get_size)
+		return -EOPNOTSUPP;
+
+	return entity->ops->get_size(entity, width, height);
+}
+EXPORT_SYMBOL_GPL(display_entity_get_size);
+
+int display_entity_get_params(struct display_entity *entity,
+			      struct display_entity_interface_params *params)
+{
+	if (!entity->ops || !entity->ops->get_params)
+		return -EOPNOTSUPP;
+
+	return entity->ops->get_params(entity, params);
+}
+EXPORT_SYMBOL_GPL(display_entity_get_params);
+
+static void display_entity_release(struct kref *ref)
+{
+	struct display_entity *entity =
+		container_of(ref, struct display_entity, ref);
+
+	if (entity->release)
+		entity->release(entity);
+}
+
+struct display_entity *display_entity_get(struct display_entity *entity)
+{
+	if (entity == NULL)
+		return NULL;
+
+	kref_get(&entity->ref);
+	return entity;
+}
+EXPORT_SYMBOL_GPL(display_entity_get);
+
+void display_entity_put(struct display_entity *entity)
+{
+	kref_put(&entity->ref, display_entity_release);
+}
+EXPORT_SYMBOL_GPL(display_entity_put);
+
+int __must_check __display_entity_register(struct display_entity *entity,
+					   struct module *owner)
+{
+	struct video_source *src;
+
+	kref_init(&entity->ref);
+	entity->owner = owner;
+	entity->state = DISPLAY_ENTITY_STATE_OFF;
+	entity->source = NULL;
+
+	src = video_source_bind(entity);
+	if (!src)
+		return -EPROBE_DEFER;
+
+	mutex_lock(&display_entity_mutex);
+	list_add(&entity->list, &display_entity_list);
+	mutex_unlock(&display_entity_mutex);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(__display_entity_register);
+
+void display_entity_unregister(struct display_entity *entity)
+{
+	video_source_unbind(entity);
+
+	mutex_lock(&display_entity_mutex);
+
+	list_del(&entity->list);
+	mutex_unlock(&display_entity_mutex);
+
+	display_entity_put(entity);
+}
+EXPORT_SYMBOL_GPL(display_entity_unregister);
+
+/* -----------------------------------------------------------------------------
+ * Video Source
+ */
+
+static LIST_HEAD(video_source_list);
+static DEFINE_MUTEX(video_source_mutex);
+
+static void video_source_release(struct kref *ref)
+{
+	struct video_source *src =
+		container_of(ref, struct video_source, ref);
+
+	if (src->release)
+		src->release(src);
+}
+
+static struct video_source *video_source_get(struct video_source *src)
+{
+	if (src == NULL)
+		return NULL;
+
+	kref_get(&src->ref);
+	if (!try_module_get(src->owner)) {
+		kref_put(&src->ref, video_source_release);
+		return NULL;
+	}
+
+	return src;
+}
+
+static void video_source_put(struct video_source *src)
+{
+	module_put(src->owner);
+	kref_put(&src->ref, video_source_release);
+}
+
+int __must_check __video_source_register(struct video_source *src,
+							struct module *owner)
+{
+	kref_init(&src->ref);
+	src->owner = owner;
+
+	mutex_lock(&video_source_mutex);
+	list_add(&src->list, &video_source_list);
+
+	mutex_unlock(&video_source_mutex);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(__video_source_register);
+
+void video_source_unregister(struct video_source *src)
+{
+	mutex_lock(&video_source_mutex);
+
+	list_del(&src->list);
+	mutex_unlock(&video_source_mutex);
+
+	kref_put(&src->ref, video_source_release);
+}
+EXPORT_SYMBOL_GPL(video_source_unregister);
+
+static struct video_source *video_source_bind(struct display_entity *entity)
+{
+	struct video_source *src = NULL;
+	int ret;
+
+	if (entity->source)
+		return entity->source;
+
+	mutex_lock(&video_source_mutex);
+
+	if (entity->of_node) {
+		struct device_node *np;
+
+		np = of_parse_phandle(entity->of_node, "video-source", 0);
+		if (!np)
+			goto unlock;
+
+		list_for_each_entry(src, &video_source_list, list) {
+			if (src->of_node == np)
+				goto found;
+		}
+
+		src = NULL;
+		goto unlock;
+	}
+
+	if (!entity->src_name)
+		goto unlock;
+
+	list_for_each_entry(src, &video_source_list, list) {
+		if (src->id != entity->src_id)
+			continue;
+		if (!strcmp(src->name, entity->src_name))
+			goto found;
+	}
+
+	src = NULL;
+	goto unlock;
+
+found:
+	video_source_get(src);
+
+	if (src->common_ops->bind) {
+		ret = src->common_ops->bind(src, entity);
+		if (ret != 0) {
+			video_source_put(src);
+			src = NULL;
+			goto unlock;
+		}
+	}
+
+	src->sink = entity;
+	entity->source = src;
+
+unlock:
+	mutex_unlock(&video_source_mutex);
+
+	return src;
+}
+
+static void video_source_unbind(struct display_entity *entity)
+{
+	struct video_source *src = entity->source;
+
+	if (!src)
+		return;
+
+	if (src->common_ops && src->common_ops->unbind)
+		src->common_ops->unbind(src, entity);
+
+	src->sink = NULL;
+	entity->source = NULL;
+
+	video_source_put(src);
+}
+
+MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
+MODULE_DESCRIPTION("Display Core");
+MODULE_LICENSE("GPL");