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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright (C) 2014 Texas Instruments4 * Author: Tomi Valkeinen <tomi.valkeinen@ti.com>5 */6 7/*8 * As omapdss panel drivers are omapdss specific, but we want to define the9 * DT-data in generic manner, we convert the compatible strings of the panel and10 * encoder nodes from "panel-foo" to "omapdss,panel-foo". This way we can have11 * both correct DT data and omapdss specific drivers.12 *13 * When we get generic panel drivers to the kernel, this file will be removed.14 */15 16#include <linux/kernel.h>17#include <linux/of.h>18#include <linux/of_graph.h>19#include <linux/slab.h>20#include <linux/list.h>21 22static struct list_head dss_conv_list __initdata;23 24static const char prefix[] __initconst = "omapdss,";25 26struct dss_conv_node {27 struct list_head list;28 struct device_node *node;29 bool root;30};31 32static int __init omapdss_count_strings(const struct property *prop)33{34 const char *p = prop->value;35 int l = 0, total = 0;36 int i;37 38 for (i = 0; total < prop->length; total += l, p += l, i++)39 l = strlen(p) + 1;40 41 return i;42}43 44static void __init omapdss_update_prop(struct device_node *node, char *compat,45 int len)46{47 struct property *prop;48 49 prop = kzalloc(sizeof(*prop), GFP_KERNEL);50 if (!prop)51 return;52 53 prop->name = "compatible";54 prop->value = compat;55 prop->length = len;56 57 of_update_property(node, prop);58}59 60static void __init omapdss_prefix_strcpy(char *dst, int dst_len,61 const char *src, int src_len)62{63 size_t total = 0;64 65 while (total < src_len) {66 size_t l = strlen(src) + 1;67 68 strcpy(dst, prefix);69 dst += strlen(prefix);70 71 strcpy(dst, src);72 dst += l;73 74 src += l;75 total += l;76 }77}78 79/* prepend compatible property strings with "omapdss," */80static void __init omapdss_omapify_node(struct device_node *node)81{82 struct property *prop;83 char *new_compat;84 int num_strs;85 int new_len;86 87 prop = of_find_property(node, "compatible", NULL);88 89 if (!prop || !prop->value)90 return;91 92 if (strnlen(prop->value, prop->length) >= prop->length)93 return;94 95 /* is it already prefixed? */96 if (strncmp(prefix, prop->value, strlen(prefix)) == 0)97 return;98 99 num_strs = omapdss_count_strings(prop);100 101 new_len = prop->length + strlen(prefix) * num_strs;102 new_compat = kmalloc(new_len, GFP_KERNEL);103 if (!new_compat)104 return;105 106 omapdss_prefix_strcpy(new_compat, new_len, prop->value, prop->length);107 108 omapdss_update_prop(node, new_compat, new_len);109}110 111static void __init omapdss_add_to_list(struct device_node *node, bool root)112{113 struct dss_conv_node *n = kmalloc(sizeof(struct dss_conv_node),114 GFP_KERNEL);115 if (n) {116 n->node = node;117 n->root = root;118 list_add(&n->list, &dss_conv_list);119 }120}121 122static bool __init omapdss_list_contains(const struct device_node *node)123{124 struct dss_conv_node *n;125 126 list_for_each_entry(n, &dss_conv_list, list) {127 if (n->node == node)128 return true;129 }130 131 return false;132}133 134static void __init omapdss_walk_device(struct device_node *node, bool root)135{136 struct device_node *n;137 138 omapdss_add_to_list(node, root);139 140 /*141 * of_graph_get_remote_port_parent() prints an error if there is no142 * port/ports node. To avoid that, check first that there's the node.143 */144 n = of_get_child_by_name(node, "ports");145 if (!n)146 n = of_get_child_by_name(node, "port");147 if (!n)148 return;149 150 of_node_put(n);151 152 for_each_endpoint_of_node(node, n) {153 struct device_node *pn;154 155 pn = of_graph_get_remote_port_parent(n);156 157 if (!pn)158 continue;159 160 if (!of_device_is_available(pn) || omapdss_list_contains(pn)) {161 of_node_put(pn);162 continue;163 }164 165 omapdss_walk_device(pn, false);166 }167}168 169static const struct of_device_id omapdss_of_match[] __initconst = {170 { .compatible = "ti,omap2-dss", },171 { .compatible = "ti,omap3-dss", },172 { .compatible = "ti,omap4-dss", },173 { .compatible = "ti,omap5-dss", },174 { .compatible = "ti,dra7-dss", },175 {},176};177 178static int __init omapdss_boot_init(void)179{180 struct device_node *dss, *child;181 182 INIT_LIST_HEAD(&dss_conv_list);183 184 dss = of_find_matching_node(NULL, omapdss_of_match);185 186 if (dss == NULL || !of_device_is_available(dss)) {187 of_node_put(dss);188 return 0;189 }190 191 omapdss_walk_device(dss, true);192 193 for_each_available_child_of_node(dss, child) {194 if (!of_property_present(child, "compatible"))195 continue;196 197 omapdss_walk_device(child, true);198 }199 200 while (!list_empty(&dss_conv_list)) {201 struct dss_conv_node *n;202 203 n = list_first_entry(&dss_conv_list, struct dss_conv_node,204 list);205 206 if (!n->root)207 omapdss_omapify_node(n->node);208 209 list_del(&n->list);210 of_node_put(n->node);211 kfree(n);212 }213 214 return 0;215}216 217subsys_initcall(omapdss_boot_init);218