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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * OMAP Display Subsystem Base4 *5 * Copyright (C) 2015-2017 Texas Instruments Incorporated - https://www.ti.com/6 */7 8#include <linux/kernel.h>9#include <linux/list.h>10#include <linux/module.h>11#include <linux/mutex.h>12#include <linux/of.h>13#include <linux/of_graph.h>14#include <linux/platform_device.h>15 16#include "dss.h"17#include "omapdss.h"18 19struct dispc_device *dispc_get_dispc(struct dss_device *dss)20{21 return dss->dispc;22}23 24/* -----------------------------------------------------------------------------25 * OMAP DSS Devices Handling26 */27 28static LIST_HEAD(omapdss_devices_list);29static DEFINE_MUTEX(omapdss_devices_lock);30 31void omapdss_device_register(struct omap_dss_device *dssdev)32{33 mutex_lock(&omapdss_devices_lock);34 list_add_tail(&dssdev->list, &omapdss_devices_list);35 mutex_unlock(&omapdss_devices_lock);36}37 38void omapdss_device_unregister(struct omap_dss_device *dssdev)39{40 mutex_lock(&omapdss_devices_lock);41 list_del(&dssdev->list);42 mutex_unlock(&omapdss_devices_lock);43}44 45static bool omapdss_device_is_registered(struct device_node *node)46{47 struct omap_dss_device *dssdev;48 bool found = false;49 50 mutex_lock(&omapdss_devices_lock);51 52 list_for_each_entry(dssdev, &omapdss_devices_list, list) {53 if (dssdev->dev->of_node == node) {54 found = true;55 break;56 }57 }58 59 mutex_unlock(&omapdss_devices_lock);60 return found;61}62 63struct omap_dss_device *omapdss_device_get(struct omap_dss_device *dssdev)64{65 if (get_device(dssdev->dev) == NULL)66 return NULL;67 68 return dssdev;69}70 71void omapdss_device_put(struct omap_dss_device *dssdev)72{73 put_device(dssdev->dev);74}75 76struct omap_dss_device *omapdss_find_device_by_node(struct device_node *node)77{78 struct omap_dss_device *dssdev;79 80 list_for_each_entry(dssdev, &omapdss_devices_list, list) {81 if (dssdev->dev->of_node == node)82 return omapdss_device_get(dssdev);83 }84 85 return NULL;86}87 88/*89 * Search for the next output device starting at @from. Release the reference to90 * the @from device, and acquire a reference to the returned device if found.91 */92struct omap_dss_device *omapdss_device_next_output(struct omap_dss_device *from)93{94 struct omap_dss_device *dssdev;95 struct list_head *list;96 97 mutex_lock(&omapdss_devices_lock);98 99 if (list_empty(&omapdss_devices_list)) {100 dssdev = NULL;101 goto done;102 }103 104 /*105 * Start from the from entry if given or from omapdss_devices_list106 * otherwise.107 */108 list = from ? &from->list : &omapdss_devices_list;109 110 list_for_each_entry(dssdev, list, list) {111 /*112 * Stop if we reach the omapdss_devices_list, that's the end of113 * the list.114 */115 if (&dssdev->list == &omapdss_devices_list) {116 dssdev = NULL;117 goto done;118 }119 120 if (dssdev->id && dssdev->bridge)121 goto done;122 }123 124 dssdev = NULL;125 126done:127 if (from)128 omapdss_device_put(from);129 if (dssdev)130 omapdss_device_get(dssdev);131 132 mutex_unlock(&omapdss_devices_lock);133 return dssdev;134}135 136static bool omapdss_device_is_connected(struct omap_dss_device *dssdev)137{138 return dssdev->dss;139}140 141int omapdss_device_connect(struct dss_device *dss,142 struct omap_dss_device *src,143 struct omap_dss_device *dst)144{145 dev_dbg(&dss->pdev->dev, "connect(%s, %s)\n",146 src ? dev_name(src->dev) : "NULL",147 dst ? dev_name(dst->dev) : "NULL");148 149 if (!dst) {150 /*151 * The destination is NULL when the source is connected to a152 * bridge instead of a DSS device. Stop here, we will attach153 * the bridge later when we will have a DRM encoder.154 */155 return src && src->bridge ? 0 : -EINVAL;156 }157 158 if (omapdss_device_is_connected(dst))159 return -EBUSY;160 161 dst->dss = dss;162 163 return 0;164}165 166void omapdss_device_disconnect(struct omap_dss_device *src,167 struct omap_dss_device *dst)168{169 struct dss_device *dss = src ? src->dss : dst->dss;170 171 dev_dbg(&dss->pdev->dev, "disconnect(%s, %s)\n",172 src ? dev_name(src->dev) : "NULL",173 dst ? dev_name(dst->dev) : "NULL");174 175 if (!dst) {176 WARN_ON(!src->bridge);177 return;178 }179 180 if (!dst->id && !omapdss_device_is_connected(dst)) {181 WARN_ON(1);182 return;183 }184 185 dst->dss = NULL;186}187 188/* -----------------------------------------------------------------------------189 * Components Handling190 */191 192static struct list_head omapdss_comp_list;193 194struct omapdss_comp_node {195 struct list_head list;196 struct device_node *node;197 bool dss_core_component;198 const char *compat;199};200 201static bool omapdss_list_contains(const struct device_node *node)202{203 struct omapdss_comp_node *comp;204 205 list_for_each_entry(comp, &omapdss_comp_list, list) {206 if (comp->node == node)207 return true;208 }209 210 return false;211}212 213static void omapdss_walk_device(struct device *dev, struct device_node *node,214 bool dss_core)215{216 struct omapdss_comp_node *comp;217 struct device_node *n;218 const char *compat;219 int ret;220 221 ret = of_property_read_string(node, "compatible", &compat);222 if (ret < 0)223 return;224 225 comp = devm_kzalloc(dev, sizeof(*comp), GFP_KERNEL);226 if (comp) {227 comp->node = node;228 comp->dss_core_component = dss_core;229 comp->compat = compat;230 list_add(&comp->list, &omapdss_comp_list);231 }232 233 /*234 * of_graph_get_remote_port_parent() prints an error if there is no235 * port/ports node. To avoid that, check first that there's the node.236 */237 n = of_get_child_by_name(node, "ports");238 if (!n)239 n = of_get_child_by_name(node, "port");240 if (!n)241 return;242 243 of_node_put(n);244 245 for_each_endpoint_of_node(node, n) {246 struct device_node *pn = of_graph_get_remote_port_parent(n);247 248 if (!pn)249 continue;250 251 if (!of_device_is_available(pn) || omapdss_list_contains(pn)) {252 of_node_put(pn);253 continue;254 }255 256 omapdss_walk_device(dev, pn, false);257 }258}259 260void omapdss_gather_components(struct device *dev)261{262 struct device_node *child;263 264 INIT_LIST_HEAD(&omapdss_comp_list);265 266 omapdss_walk_device(dev, dev->of_node, true);267 268 for_each_available_child_of_node(dev->of_node, child)269 omapdss_walk_device(dev, child, true);270}271 272static bool omapdss_component_is_loaded(struct omapdss_comp_node *comp)273{274 if (comp->dss_core_component)275 return true;276 if (!strstarts(comp->compat, "omapdss,"))277 return true;278 if (omapdss_device_is_registered(comp->node))279 return true;280 281 return false;282}283 284bool omapdss_stack_is_ready(void)285{286 struct omapdss_comp_node *comp;287 288 list_for_each_entry(comp, &omapdss_comp_list, list) {289 if (!omapdss_component_is_loaded(comp))290 return false;291 }292 293 return true;294}295