1 /* 2 * Copyright (C) 2013 Texas Instruments 3 * Author: Tomi Valkeinen <tomi.valkeinen@ti.com> 4 * 5 * This program is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 as published by 7 * the Free Software Foundation. 8 * 9 * This program is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 12 * more details. 13 */ 14 15 #include <linux/device.h> 16 #include <linux/err.h> 17 #include <linux/module.h> 18 #include <linux/of.h> 19 #include <linux/of_graph.h> 20 #include <linux/seq_file.h> 21 22 #include <video/omapfb_dss.h> 23 24 #include "dss.h" 25 26 struct device_node * 27 omapdss_of_get_next_port(const struct device_node *parent, 28 struct device_node *prev) 29 { 30 struct device_node *port = NULL; 31 32 if (!parent) 33 return NULL; 34 35 if (!prev) { 36 struct device_node *ports; 37 /* 38 * It's the first call, we have to find a port subnode 39 * within this node or within an optional 'ports' node. 40 */ 41 ports = of_get_child_by_name(parent, "ports"); 42 if (ports) 43 parent = ports; 44 45 port = of_get_child_by_name(parent, "port"); 46 47 /* release the 'ports' node */ 48 of_node_put(ports); 49 } else { 50 struct device_node *ports; 51 52 ports = of_get_parent(prev); 53 if (!ports) 54 return NULL; 55 56 do { 57 port = of_get_next_child(ports, prev); 58 if (!port) { 59 of_node_put(ports); 60 return NULL; 61 } 62 prev = port; 63 } while (!of_node_name_eq(port, "port")); 64 65 of_node_put(ports); 66 } 67 68 return port; 69 } 70 EXPORT_SYMBOL_GPL(omapdss_of_get_next_port); 71 72 struct device_node * 73 omapdss_of_get_next_endpoint(const struct device_node *parent, 74 struct device_node *prev) 75 { 76 struct device_node *ep = NULL; 77 78 if (!parent) 79 return NULL; 80 81 do { 82 ep = of_get_next_child(parent, prev); 83 if (!ep) 84 return NULL; 85 prev = ep; 86 } while (!of_node_name_eq(ep, "endpoint")); 87 88 return ep; 89 } 90 EXPORT_SYMBOL_GPL(omapdss_of_get_next_endpoint); 91 92 struct device_node *dss_of_port_get_parent_device(struct device_node *port) 93 { 94 struct device_node *np; 95 int i; 96 97 if (!port) 98 return NULL; 99 100 np = of_get_parent(port); 101 102 for (i = 0; i < 2 && np; ++i) { 103 struct property *prop; 104 105 prop = of_find_property(np, "compatible", NULL); 106 107 if (prop) 108 return np; 109 110 np = of_get_next_parent(np); 111 } 112 113 return NULL; 114 } 115 116 u32 dss_of_port_get_port_number(struct device_node *port) 117 { 118 int r; 119 u32 reg; 120 121 r = of_property_read_u32(port, "reg", ®); 122 if (r) 123 reg = 0; 124 125 return reg; 126 } 127 128 static struct device_node *omapdss_of_get_remote_port(const struct device_node *node) 129 { 130 struct device_node *np; 131 132 np = of_graph_get_remote_endpoint(node); 133 if (!np) 134 return NULL; 135 136 np = of_get_next_parent(np); 137 138 return np; 139 } 140 141 struct device_node * 142 omapdss_of_get_first_endpoint(const struct device_node *parent) 143 { 144 struct device_node *port, *ep; 145 146 port = omapdss_of_get_next_port(parent, NULL); 147 148 if (!port) 149 return NULL; 150 151 ep = omapdss_of_get_next_endpoint(port, NULL); 152 153 of_node_put(port); 154 155 return ep; 156 } 157 EXPORT_SYMBOL_GPL(omapdss_of_get_first_endpoint); 158 159 struct omap_dss_device * 160 omapdss_of_find_source_for_first_ep(struct device_node *node) 161 { 162 struct device_node *ep; 163 struct device_node *src_port; 164 struct omap_dss_device *src; 165 166 ep = omapdss_of_get_first_endpoint(node); 167 if (!ep) 168 return ERR_PTR(-EINVAL); 169 170 src_port = omapdss_of_get_remote_port(ep); 171 if (!src_port) { 172 of_node_put(ep); 173 return ERR_PTR(-EINVAL); 174 } 175 176 of_node_put(ep); 177 178 src = omap_dss_find_output_by_port_node(src_port); 179 180 of_node_put(src_port); 181 182 return src ? src : ERR_PTR(-EPROBE_DEFER); 183 } 184 EXPORT_SYMBOL_GPL(omapdss_of_find_source_for_first_ep); 185