LXR linux/drivers/gpu/drm/omapdrm/dss/base.c

   1/*
   2 * OMAP Display Subsystem Base
   3 *
   4 * Copyright (C) 2015-2017 Texas Instruments Incorporated - http://www.ti.com/
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License version 2 as
   8 * published by the Free Software Foundation.
   9 *
  10 * This program is distributed in the hope that it will be useful, but
  11 * WITHOUT ANY WARRANTY; without even the implied warranty of
  12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13 * General Public License for more details.
  14 */
  15
  16#include <linux/kernel.h>
  17#include <linux/module.h>
  18#include <linux/of.h>
  19#include <linux/of_graph.h>
  20#include <linux/list.h>
  21
  22#include "dss.h"
  23#include "omapdss.h"
  24
  25static struct dss_device *dss_device;
  26
  27static struct list_head omapdss_comp_list;
  28
  29struct omapdss_comp_node {
  30        struct list_head list;
  31        struct device_node *node;
  32        bool dss_core_component;
  33};
  34
  35struct dss_device *omapdss_get_dss(void)
  36{
  37        return dss_device;
  38}
  39EXPORT_SYMBOL(omapdss_get_dss);
  40
  41void omapdss_set_dss(struct dss_device *dss)
  42{
  43        dss_device = dss;
  44}
  45EXPORT_SYMBOL(omapdss_set_dss);
  46
  47struct dispc_device *dispc_get_dispc(struct dss_device *dss)
  48{
  49        return dss->dispc;
  50}
  51EXPORT_SYMBOL(dispc_get_dispc);
  52
  53const struct dispc_ops *dispc_get_ops(struct dss_device *dss)
  54{
  55        return dss->dispc_ops;
  56}
  57EXPORT_SYMBOL(dispc_get_ops);
  58
  59static bool omapdss_list_contains(const struct device_node *node)
  60{
  61        struct omapdss_comp_node *comp;
  62
  63        list_for_each_entry(comp, &omapdss_comp_list, list) {
  64                if (comp->node == node)
  65                        return true;
  66        }
  67
  68        return false;
  69}
  70
  71static void omapdss_walk_device(struct device *dev, struct device_node *node,
  72                                bool dss_core)
  73{
  74        struct device_node *n;
  75        struct omapdss_comp_node *comp = devm_kzalloc(dev, sizeof(*comp),
  76                                                      GFP_KERNEL);
  77
  78        if (comp) {
  79                comp->node = node;
  80                comp->dss_core_component = dss_core;
  81                list_add(&comp->list, &omapdss_comp_list);
  82        }
  83
  84        /*
  85         * of_graph_get_remote_port_parent() prints an error if there is no
  86         * port/ports node. To avoid that, check first that there's the node.
  87         */
  88        n = of_get_child_by_name(node, "ports");
  89        if (!n)
  90                n = of_get_child_by_name(node, "port");
  91        if (!n)
  92                return;
  93
  94        of_node_put(n);
  95
  96        n = NULL;
  97        while ((n = of_graph_get_next_endpoint(node, n)) != NULL) {
  98                struct device_node *pn = of_graph_get_remote_port_parent(n);
  99
 100                if (!pn)
 101                        continue;
 102
 103                if (!of_device_is_available(pn) || omapdss_list_contains(pn)) {
 104                        of_node_put(pn);
 105                        continue;
 106                }
 107
 108                omapdss_walk_device(dev, pn, false);
 109        }
 110}
 111
 112void omapdss_gather_components(struct device *dev)
 113{
 114        struct device_node *child;
 115
 116        INIT_LIST_HEAD(&omapdss_comp_list);
 117
 118        omapdss_walk_device(dev, dev->of_node, true);
 119
 120        for_each_available_child_of_node(dev->of_node, child) {
 121                if (!of_find_property(child, "compatible", NULL))
 122                        continue;
 123
 124                omapdss_walk_device(dev, child, true);
 125        }
 126}
 127EXPORT_SYMBOL(omapdss_gather_components);
 128
 129static bool omapdss_component_is_loaded(struct omapdss_comp_node *comp)
 130{
 131        if (comp->dss_core_component)
 132                return true;
 133        if (omapdss_component_is_display(comp->node))
 134                return true;
 135        if (omapdss_component_is_output(comp->node))
 136                return true;
 137
 138        return false;
 139}
 140
 141bool omapdss_stack_is_ready(void)
 142{
 143        struct omapdss_comp_node *comp;
 144
 145        list_for_each_entry(comp, &omapdss_comp_list, list) {
 146                if (!omapdss_component_is_loaded(comp))
 147                        return false;
 148        }
 149
 150        return true;
 151}
 152EXPORT_SYMBOL(omapdss_stack_is_ready);
 153
 154MODULE_AUTHOR("Tomi Valkeinen <tomi.valkeinen@ti.com>");
 155MODULE_DESCRIPTION("OMAP Display Subsystem Base");
 156MODULE_LICENSE("GPL v2");
 157