drivers/gpu/drm/omapdrm/dss/base.c - linux - Git at Google

 // 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"

 static struct dss_device *dss_device;

 struct dss_device *omapdss_get_dss(void)
 {
 	return dss_device;
 }
 EXPORT_SYMBOL(omapdss_get_dss);

 void omapdss_set_dss(struct dss_device *dss)
 {
 	dss_device = dss;
 }
 EXPORT_SYMBOL(omapdss_set_dss);

 struct dispc_device *dispc_get_dispc(struct dss_device *dss)
 {
 	return dss->dispc;
 }
 EXPORT_SYMBOL(dispc_get_dispc);

 const struct dispc_ops *dispc_get_ops(struct dss_device *dss)
 {
 	return dss->dispc_ops;
 }
 EXPORT_SYMBOL(dispc_get_ops);


 /* -----------------------------------------------------------------------------
  * 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);
 }
 EXPORT_SYMBOL_GPL(omapdss_device_register);

 void omapdss_device_unregister(struct omap_dss_device *dssdev)
 {
 	mutex_lock(&omapdss_devices_lock);
 	list_del(&dssdev->list);
 	mutex_unlock(&omapdss_devices_lock);
 }
 EXPORT_SYMBOL_GPL(omapdss_device_unregister);

 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 (!try_module_get(dssdev->owner))
 		return NULL;

 	if (get_device(dssdev->dev) == NULL) {
 		module_put(dssdev->owner);
 		return NULL;
 	}

 	return dssdev;
 }
 EXPORT_SYMBOL(omapdss_device_get);

 void omapdss_device_put(struct omap_dss_device *dssdev)
 {
 	put_device(dssdev->dev);
 	module_put(dssdev->owner);
 }
 EXPORT_SYMBOL(omapdss_device_put);

 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->next || 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;
 }
 EXPORT_SYMBOL(omapdss_device_next_output);

 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)
 {
 	int ret;

 	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;

 	if (dst->ops && dst->ops->connect) {
 		ret = dst->ops->connect(src, dst);
 		if (ret < 0) {
 			dst->dss = NULL;
 			return ret;
 		}
 	}

 	return 0;
 }
 EXPORT_SYMBOL_GPL(omapdss_device_connect);

 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(!dst->display);
 		return;
 	}

 	WARN_ON(dst->state != OMAP_DSS_DISPLAY_DISABLED);

 	if (dst->ops && dst->ops->disconnect)
 		dst->ops->disconnect(src, dst);
 	dst->dss = NULL;
 }
 EXPORT_SYMBOL_GPL(omapdss_device_disconnect);

 void omapdss_device_enable(struct omap_dss_device *dssdev)
 {
 	if (!dssdev)
 		return;

 	if (dssdev->ops && dssdev->ops->enable)
 		dssdev->ops->enable(dssdev);

 	omapdss_device_enable(dssdev->next);

 	dssdev->state = OMAP_DSS_DISPLAY_ACTIVE;
 }
 EXPORT_SYMBOL_GPL(omapdss_device_enable);

 void omapdss_device_disable(struct omap_dss_device *dssdev)
 {
 	if (!dssdev)
 		return;

 	omapdss_device_disable(dssdev->next);

 	if (dssdev->ops && dssdev->ops->disable)
 		dssdev->ops->disable(dssdev);
 }
 EXPORT_SYMBOL_GPL(omapdss_device_disable);

 /* -----------------------------------------------------------------------------
  * 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);
 }
 EXPORT_SYMBOL(omapdss_gather_components);

 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;
 }
 EXPORT_SYMBOL(omapdss_stack_is_ready);

 MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@ti.com>");
 MODULE_DESCRIPTION("OMAP Display Subsystem Base");
 MODULE_LICENSE("GPL v2");
	// 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"

	static struct dss_device *dss_device;

	struct dss_device *omapdss_get_dss(void)
	{
	return dss_device;
	}
	EXPORT_SYMBOL(omapdss_get_dss);

	void omapdss_set_dss(struct dss_device *dss)
	{
	dss_device = dss;
	}
	EXPORT_SYMBOL(omapdss_set_dss);

	struct dispc_device dispc_get_dispc(struct dss_device dss)
	{
	return dss->dispc;
	}
	EXPORT_SYMBOL(dispc_get_dispc);

	const struct dispc_ops dispc_get_ops(struct dss_device dss)
	{
	return dss->dispc_ops;
	}
	EXPORT_SYMBOL(dispc_get_ops);


	/* -----------------------------------------------------------------------------
	* 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);
	}
	EXPORT_SYMBOL_GPL(omapdss_device_register);

	void omapdss_device_unregister(struct omap_dss_device *dssdev)
	{
	mutex_lock(&omapdss_devices_lock);
	list_del(&dssdev->list);
	mutex_unlock(&omapdss_devices_lock);
	}
	EXPORT_SYMBOL_GPL(omapdss_device_unregister);

	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 (!try_module_get(dssdev->owner))
	return NULL;

	if (get_device(dssdev->dev) == NULL) {
	module_put(dssdev->owner);
	return NULL;
	}

	return dssdev;
	}
	EXPORT_SYMBOL(omapdss_device_get);

	void omapdss_device_put(struct omap_dss_device *dssdev)
	{
	put_device(dssdev->dev);
	module_put(dssdev->owner);
	}
	EXPORT_SYMBOL(omapdss_device_put);

	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->next \|\| 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;
	}
	EXPORT_SYMBOL(omapdss_device_next_output);

	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)
	{
	int ret;

	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;

	if (dst->ops && dst->ops->connect) {
	ret = dst->ops->connect(src, dst);
	if (ret < 0) {
	dst->dss = NULL;
	return ret;
	}
	}

	return 0;
	}
	EXPORT_SYMBOL_GPL(omapdss_device_connect);

	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(!dst->display);
	return;
	}

	WARN_ON(dst->state != OMAP_DSS_DISPLAY_DISABLED);

	if (dst->ops && dst->ops->disconnect)
	dst->ops->disconnect(src, dst);
	dst->dss = NULL;
	}
	EXPORT_SYMBOL_GPL(omapdss_device_disconnect);

	void omapdss_device_enable(struct omap_dss_device *dssdev)
	{
	if (!dssdev)
	return;

	if (dssdev->ops && dssdev->ops->enable)
	dssdev->ops->enable(dssdev);

	omapdss_device_enable(dssdev->next);

	dssdev->state = OMAP_DSS_DISPLAY_ACTIVE;
	}
	EXPORT_SYMBOL_GPL(omapdss_device_enable);

	void omapdss_device_disable(struct omap_dss_device *dssdev)
	{
	if (!dssdev)
	return;

	omapdss_device_disable(dssdev->next);

	if (dssdev->ops && dssdev->ops->disable)
	dssdev->ops->disable(dssdev);
	}
	EXPORT_SYMBOL_GPL(omapdss_device_disable);

	/* -----------------------------------------------------------------------------
	* 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);
	}
	EXPORT_SYMBOL(omapdss_gather_components);

	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;
	}
	EXPORT_SYMBOL(omapdss_stack_is_ready);

	MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@ti.com>");
	MODULE_DESCRIPTION("OMAP Display Subsystem Base");
	MODULE_LICENSE("GPL v2");