1 files changed, 295 insertions, 0 deletions
diff --git a/drivers/gpu/drm/omapdrm/dss/base.c b/drivers/gpu/drm/omapdrm/dss/base.c
new file mode 100644
index 000000000..050ca7eaf
--- /dev/null
+++ b/drivers/gpu/drm/omapdrm/dss/base.c
@@ -0,0 +1,295 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * OMAP Display Subsystem Base
+ *
+ * Copyright (C) 2015-2017 Texas Instruments Incorporated - https://www.ti.com/
+ */
+
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/of_graph.h>
+#include <linux/platform_device.h>
+
+#include "dss.h"
+#include "omapdss.h"
+
+struct dispc_device *dispc_get_dispc(struct dss_device *dss)
+{
+	return dss->dispc;
+}
+
+/* -----------------------------------------------------------------------------
+ * OMAP DSS Devices Handling
+ */
+
+static LIST_HEAD(omapdss_devices_list);
+static DEFINE_MUTEX(omapdss_devices_lock);
+
+void omapdss_device_register(struct omap_dss_device *dssdev)
+{
+	mutex_lock(&omapdss_devices_lock);
+	list_add_tail(&dssdev->list, &omapdss_devices_list);
+	mutex_unlock(&omapdss_devices_lock);
+}
+
+void omapdss_device_unregister(struct omap_dss_device *dssdev)
+{
+	mutex_lock(&omapdss_devices_lock);
+	list_del(&dssdev->list);
+	mutex_unlock(&omapdss_devices_lock);
+}
+
+static bool omapdss_device_is_registered(struct device_node *node)
+{
+	struct omap_dss_device *dssdev;
+	bool found = false;
+
+	mutex_lock(&omapdss_devices_lock);
+
+	list_for_each_entry(dssdev, &omapdss_devices_list, list) {
+		if (dssdev->dev->of_node == node) {
+			found = true;
+			break;
+		}
+	}
+
+	mutex_unlock(&omapdss_devices_lock);
+	return found;
+}
+
+struct omap_dss_device *omapdss_device_get(struct omap_dss_device *dssdev)
+{
+	if (get_device(dssdev->dev) == NULL)
+		return NULL;
+
+	return dssdev;
+}
+
+void omapdss_device_put(struct omap_dss_device *dssdev)
+{
+	put_device(dssdev->dev);
+}
+
+struct omap_dss_device *omapdss_find_device_by_node(struct device_node *node)
+{
+	struct omap_dss_device *dssdev;
+
+	list_for_each_entry(dssdev, &omapdss_devices_list, list) {
+		if (dssdev->dev->of_node == node)
+			return omapdss_device_get(dssdev);
+	}
+
+	return NULL;
+}
+
+/*
+ * Search for the next output device starting at @from. Release the reference to
+ * the @from device, and acquire a reference to the returned device if found.
+ */
+struct omap_dss_device *omapdss_device_next_output(struct omap_dss_device *from)
+{
+	struct omap_dss_device *dssdev;
+	struct list_head *list;
+
+	mutex_lock(&omapdss_devices_lock);
+
+	if (list_empty(&omapdss_devices_list)) {
+		dssdev = NULL;
+		goto done;
+	}
+
+	/*
+	 * Start from the from entry if given or from omapdss_devices_list
+	 * otherwise.
+	 */
+	list = from ? &from->list : &omapdss_devices_list;
+
+	list_for_each_entry(dssdev, list, list) {
+		/*
+		 * Stop if we reach the omapdss_devices_list, that's the end of
+		 * the list.
+		 */
+		if (&dssdev->list == &omapdss_devices_list) {
+			dssdev = NULL;
+			goto done;
+		}
+
+		if (dssdev->id && dssdev->bridge)
+			goto done;
+	}
+
+	dssdev = NULL;
+
+done:
+	if (from)
+		omapdss_device_put(from);
+	if (dssdev)
+		omapdss_device_get(dssdev);
+
+	mutex_unlock(&omapdss_devices_lock);
+	return dssdev;
+}
+
+static bool omapdss_device_is_connected(struct omap_dss_device *dssdev)
+{
+	return dssdev->dss;
+}
+
+int omapdss_device_connect(struct dss_device *dss,
+			   struct omap_dss_device *src,
+			   struct omap_dss_device *dst)
+{
+	dev_dbg(&dss->pdev->dev, "connect(%s, %s)\n",
+		src ? dev_name(src->dev) : "NULL",
+		dst ? dev_name(dst->dev) : "NULL");
+
+	if (!dst) {
+		/*
+		 * The destination is NULL when the source is connected to a
+		 * bridge instead of a DSS device. Stop here, we will attach
+		 * the bridge later when we will have a DRM encoder.
+		 */
+		return src && src->bridge ? 0 : -EINVAL;
+	}
+
+	if (omapdss_device_is_connected(dst))
+		return -EBUSY;
+
+	dst->dss = dss;
+
+	return 0;
+}
+
+void omapdss_device_disconnect(struct omap_dss_device *src,
+			       struct omap_dss_device *dst)
+{
+	struct dss_device *dss = src ? src->dss : dst->dss;
+
+	dev_dbg(&dss->pdev->dev, "disconnect(%s, %s)\n",
+		src ? dev_name(src->dev) : "NULL",
+		dst ? dev_name(dst->dev) : "NULL");
+
+	if (!dst) {
+		WARN_ON(!src->bridge);
+		return;
+	}
+
+	if (!dst->id && !omapdss_device_is_connected(dst)) {
+		WARN_ON(1);
+		return;
+	}
+
+	dst->dss = NULL;
+}
+
+/* -----------------------------------------------------------------------------
+ * Components Handling
+ */
+
+static struct list_head omapdss_comp_list;
+
+struct omapdss_comp_node {
+	struct list_head list;
+	struct device_node *node;
+	bool dss_core_component;
+	const char *compat;
+};
+
+static bool omapdss_list_contains(const struct device_node *node)
+{
+	struct omapdss_comp_node *comp;
+
+	list_for_each_entry(comp, &omapdss_comp_list, list) {
+		if (comp->node == node)
+			return true;
+	}
+
+	return false;
+}
+
+static void omapdss_walk_device(struct device *dev, struct device_node *node,
+				bool dss_core)
+{
+	struct omapdss_comp_node *comp;
+	struct device_node *n;
+	const char *compat;
+	int ret;
+
+	ret = of_property_read_string(node, "compatible", &compat);
+	if (ret < 0)
+		return;
+
+	comp = devm_kzalloc(dev, sizeof(*comp), GFP_KERNEL);
+	if (comp) {
+		comp->node = node;
+		comp->dss_core_component = dss_core;
+		comp->compat = compat;
+		list_add(&comp->list, &omapdss_comp_list);
+	}
+
+	/*
+	 * of_graph_get_remote_port_parent() prints an error if there is no
+	 * port/ports node. To avoid that, check first that there's the node.
+	 */
+	n = of_get_child_by_name(node, "ports");
+	if (!n)
+		n = of_get_child_by_name(node, "port");
+	if (!n)
+		return;
+
+	of_node_put(n);
+
+	n = NULL;
+	while ((n = of_graph_get_next_endpoint(node, n)) != NULL) {
+		struct device_node *pn = of_graph_get_remote_port_parent(n);
+
+		if (!pn)
+			continue;
+
+		if (!of_device_is_available(pn) || omapdss_list_contains(pn)) {
+			of_node_put(pn);
+			continue;
+		}
+
+		omapdss_walk_device(dev, pn, false);
+	}
+}
+
+void omapdss_gather_components(struct device *dev)
+{
+	struct device_node *child;
+
+	INIT_LIST_HEAD(&omapdss_comp_list);
+
+	omapdss_walk_device(dev, dev->of_node, true);
+
+	for_each_available_child_of_node(dev->of_node, child)
+		omapdss_walk_device(dev, child, true);
+}
+
+static bool omapdss_component_is_loaded(struct omapdss_comp_node *comp)
+{
+	if (comp->dss_core_component)
+		return true;
+	if (!strstarts(comp->compat, "omapdss,"))
+		return true;
+	if (omapdss_device_is_registered(comp->node))
+		return true;
+
+	return false;
+}
+
+bool omapdss_stack_is_ready(void)
+{
+	struct omapdss_comp_node *comp;
+
+	list_for_each_entry(comp, &omapdss_comp_list, list) {
+		if (!omapdss_component_is_loaded(comp))
+			return false;
+	}
+
+	return true;
+}