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 #include "omapdss.h"
  22
  23 static bool dss_initialized;
  24 static const struct dispc_ops *ops;
  25
  26 static struct list_head omapdss_comp_list;
  27
  28 struct omapdss_comp_node {
  29         struct list_head list;
  30         struct device_node *node;
  31         bool dss_core_component;
  32 };
  33
  34 void omapdss_set_is_initialized(bool set)
  35 {
  36         dss_initialized = set;
  37 }
  38 EXPORT_SYMBOL(omapdss_set_is_initialized);
  39
  40 bool omapdss_is_initialized(void)
  41 {
  42         return dss_initialized;
  43 }
  44 EXPORT_SYMBOL(omapdss_is_initialized);
  45
  46 void dispc_set_ops(const struct dispc_ops *o)
  47 {
  48         ops = o;
  49 }
  50 EXPORT_SYMBOL(dispc_set_ops);
  51
  52 const struct dispc_ops *dispc_get_ops(void)
  53 {
  54         return ops;
  55 }
  56 EXPORT_SYMBOL(dispc_get_ops);
  57
  58 static bool omapdss_list_contains(const struct device_node *node)
  59 {
  60         struct omapdss_comp_node *comp;
  61
  62         list_for_each_entry(comp, &omapdss_comp_list, list) {
  63                 if (comp->node == node)
  64                         return true;
  65         }
  66
  67         return false;
  68 }
  69
  70 static void omapdss_walk_device(struct device *dev, struct device_node *node,
  71                                 bool dss_core)
  72 {
  73         struct device_node *n;
  74         struct omapdss_comp_node *comp = devm_kzalloc(dev, sizeof(*comp),
  75                                                       GFP_KERNEL);
  76
  77         if (comp) {
  78                 comp->node = node;
  79                 comp->dss_core_component = dss_core;
  80                 list_add(&comp->list, &omapdss_comp_list);
  81         }
  82
  83         /*
  84          * of_graph_get_remote_port_parent() prints an error if there is no
  85          * port/ports node. To avoid that, check first that there's the node.
  86          */
  87         n = of_get_child_by_name(node, "ports");
  88         if (!n)
  89                 n = of_get_child_by_name(node, "port");
  90         if (!n)
  91                 return;
  92
  93         of_node_put(n);
  94
  95         n = NULL;
  96         while ((n = of_graph_get_next_endpoint(node, n)) != NULL) {
  97                 struct device_node *pn = of_graph_get_remote_port_parent(n);
  98
  99                 if (!pn)
 100                         continue;
 101
 102                 if (!of_device_is_available(pn) || omapdss_list_contains(pn)) {
 103                         of_node_put(pn);
 104                         continue;
 105                 }
 106
 107                 omapdss_walk_device(dev, pn, false);
 108         }
 109 }
 110
 111 void omapdss_gather_components(struct device *dev)
 112 {
 113         struct device_node *child;
 114
 115         INIT_LIST_HEAD(&omapdss_comp_list);
 116
 117         omapdss_walk_device(dev, dev->of_node, true);
 118
 119         for_each_available_child_of_node(dev->of_node, child) {
 120                 if (!of_find_property(child, "compatible", NULL))
 121                         continue;
 122
 123                 omapdss_walk_device(dev, child, true);
 124         }
 125 }
 126 EXPORT_SYMBOL(omapdss_gather_components);
 127
 128 static bool omapdss_component_is_loaded(struct omapdss_comp_node *comp)
 129 {
 130         if (comp->dss_core_component)
 131                 return true;
 132         if (omapdss_component_is_display(comp->node))
 133                 return true;
 134         if (omapdss_component_is_output(comp->node))
 135                 return true;
 136
 137         return false;
 138 }
 139
 140 bool omapdss_stack_is_ready(void)
 141 {
 142         struct omapdss_comp_node *comp;
 143
 144         list_for_each_entry(comp, &omapdss_comp_list, list) {
 145                 if (!omapdss_component_is_loaded(comp))
 146                         return false;
 147         }
 148
 149         return true;
 150 }
 151 EXPORT_SYMBOL(omapdss_stack_is_ready);
 152
 153 MODULE_AUTHOR("Tomi Valkeinen <[email protected]>");
 154 MODULE_DESCRIPTION("OMAP Display Subsystem Base");
 155 MODULE_LICENSE("GPL v2");