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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Device tree integration for the pin control subsystem4 *5 * Copyright (C) 2012 NVIDIA CORPORATION. All rights reserved.6 */7 8#include <linux/device.h>9#include <linux/of.h>10#include <linux/pinctrl/pinctrl.h>11#include <linux/slab.h>12 13#include "core.h"14#include "devicetree.h"15 16/**17 * struct pinctrl_dt_map - mapping table chunk parsed from device tree18 * @node: list node for struct pinctrl's @dt_maps field19 * @pctldev: the pin controller that allocated this struct, and will free it20 * @map: the mapping table entries21 * @num_maps: number of mapping table entries22 */23struct pinctrl_dt_map {24 struct list_head node;25 struct pinctrl_dev *pctldev;26 struct pinctrl_map *map;27 unsigned int num_maps;28};29 30static void dt_free_map(struct pinctrl_dev *pctldev,31 struct pinctrl_map *map, unsigned int num_maps)32{33 int i;34 35 for (i = 0; i < num_maps; ++i) {36 kfree_const(map[i].dev_name);37 map[i].dev_name = NULL;38 }39 40 if (pctldev) {41 const struct pinctrl_ops *ops = pctldev->desc->pctlops;42 if (ops->dt_free_map)43 ops->dt_free_map(pctldev, map, num_maps);44 } else {45 /* There is no pctldev for PIN_MAP_TYPE_DUMMY_STATE */46 kfree(map);47 }48}49 50void pinctrl_dt_free_maps(struct pinctrl *p)51{52 struct pinctrl_dt_map *dt_map, *n1;53 54 list_for_each_entry_safe(dt_map, n1, &p->dt_maps, node) {55 pinctrl_unregister_mappings(dt_map->map);56 list_del(&dt_map->node);57 dt_free_map(dt_map->pctldev, dt_map->map,58 dt_map->num_maps);59 kfree(dt_map);60 }61 62 of_node_put(p->dev->of_node);63}64 65static int dt_remember_or_free_map(struct pinctrl *p, const char *statename,66 struct pinctrl_dev *pctldev,67 struct pinctrl_map *map, unsigned int num_maps)68{69 int i;70 struct pinctrl_dt_map *dt_map;71 72 /* Initialize common mapping table entry fields */73 for (i = 0; i < num_maps; i++) {74 const char *devname;75 76 devname = kstrdup_const(dev_name(p->dev), GFP_KERNEL);77 if (!devname)78 goto err_free_map;79 80 map[i].dev_name = devname;81 map[i].name = statename;82 if (pctldev)83 map[i].ctrl_dev_name = dev_name(pctldev->dev);84 }85 86 /* Remember the converted mapping table entries */87 dt_map = kzalloc(sizeof(*dt_map), GFP_KERNEL);88 if (!dt_map)89 goto err_free_map;90 91 dt_map->pctldev = pctldev;92 dt_map->map = map;93 dt_map->num_maps = num_maps;94 list_add_tail(&dt_map->node, &p->dt_maps);95 96 return pinctrl_register_mappings(map, num_maps);97 98err_free_map:99 dt_free_map(pctldev, map, num_maps);100 return -ENOMEM;101}102 103struct pinctrl_dev *of_pinctrl_get(struct device_node *np)104{105 return get_pinctrl_dev_from_of_node(np);106}107EXPORT_SYMBOL_GPL(of_pinctrl_get);108 109static int dt_to_map_one_config(struct pinctrl *p,110 struct pinctrl_dev *hog_pctldev,111 const char *statename,112 struct device_node *np_config)113{114 struct pinctrl_dev *pctldev = NULL;115 struct device_node *np_pctldev;116 const struct pinctrl_ops *ops;117 int ret;118 struct pinctrl_map *map;119 unsigned int num_maps;120 bool allow_default = false;121 122 /* Find the pin controller containing np_config */123 np_pctldev = of_node_get(np_config);124 for (;;) {125 if (!allow_default)126 allow_default = of_property_read_bool(np_pctldev,127 "pinctrl-use-default");128 129 np_pctldev = of_get_next_parent(np_pctldev);130 if (!np_pctldev || of_node_is_root(np_pctldev)) {131 of_node_put(np_pctldev);132 ret = -ENODEV;133 /* keep deferring if modules are enabled */134 if (IS_ENABLED(CONFIG_MODULES) && !allow_default && ret < 0)135 ret = -EPROBE_DEFER;136 return ret;137 }138 /* If we're creating a hog we can use the passed pctldev */139 if (hog_pctldev && (np_pctldev == p->dev->of_node)) {140 pctldev = hog_pctldev;141 break;142 }143 pctldev = get_pinctrl_dev_from_of_node(np_pctldev);144 if (pctldev)145 break;146 /* Do not defer probing of hogs (circular loop) */147 if (np_pctldev == p->dev->of_node) {148 of_node_put(np_pctldev);149 return -ENODEV;150 }151 }152 of_node_put(np_pctldev);153 154 /*155 * Call pinctrl driver to parse device tree node, and156 * generate mapping table entries157 */158 ops = pctldev->desc->pctlops;159 if (!ops->dt_node_to_map) {160 dev_err(p->dev, "pctldev %s doesn't support DT\n",161 dev_name(pctldev->dev));162 return -ENODEV;163 }164 ret = ops->dt_node_to_map(pctldev, np_config, &map, &num_maps);165 if (ret < 0)166 return ret;167 else if (num_maps == 0) {168 /*169 * If we have no valid maps (maybe caused by empty pinctrl node170 * or typing error) ther is no need remember this, so just171 * return.172 */173 dev_info(p->dev,174 "there is not valid maps for state %s\n", statename);175 return 0;176 }177 178 /* Stash the mapping table chunk away for later use */179 return dt_remember_or_free_map(p, statename, pctldev, map, num_maps);180}181 182static int dt_remember_dummy_state(struct pinctrl *p, const char *statename)183{184 struct pinctrl_map *map;185 186 map = kzalloc(sizeof(*map), GFP_KERNEL);187 if (!map)188 return -ENOMEM;189 190 /* There is no pctldev for PIN_MAP_TYPE_DUMMY_STATE */191 map->type = PIN_MAP_TYPE_DUMMY_STATE;192 193 return dt_remember_or_free_map(p, statename, NULL, map, 1);194}195 196int pinctrl_dt_to_map(struct pinctrl *p, struct pinctrl_dev *pctldev)197{198 struct device_node *np = p->dev->of_node;199 int state, ret;200 char *propname;201 struct property *prop;202 const char *statename;203 const __be32 *list;204 int size, config;205 phandle phandle;206 struct device_node *np_config;207 208 /* CONFIG_OF enabled, p->dev not instantiated from DT */209 if (!np) {210 if (of_have_populated_dt())211 dev_dbg(p->dev,212 "no of_node; not parsing pinctrl DT\n");213 return 0;214 }215 216 /* We may store pointers to property names within the node */217 of_node_get(np);218 219 /* For each defined state ID */220 for (state = 0; ; state++) {221 /* Retrieve the pinctrl-* property */222 propname = kasprintf(GFP_KERNEL, "pinctrl-%d", state);223 if (!propname) {224 ret = -ENOMEM;225 goto err;226 }227 prop = of_find_property(np, propname, &size);228 kfree(propname);229 if (!prop) {230 if (state == 0) {231 ret = -ENODEV;232 goto err;233 }234 break;235 }236 list = prop->value;237 size /= sizeof(*list);238 239 /* Determine whether pinctrl-names property names the state */240 ret = of_property_read_string_index(np, "pinctrl-names",241 state, &statename);242 /*243 * If not, statename is just the integer state ID. But rather244 * than dynamically allocate it and have to free it later,245 * just point part way into the property name for the string.246 */247 if (ret < 0)248 statename = prop->name + strlen("pinctrl-");249 250 /* For every referenced pin configuration node in it */251 for (config = 0; config < size; config++) {252 phandle = be32_to_cpup(list++);253 254 /* Look up the pin configuration node */255 np_config = of_find_node_by_phandle(phandle);256 if (!np_config) {257 dev_err(p->dev,258 "prop %s index %i invalid phandle\n",259 prop->name, config);260 ret = -EINVAL;261 goto err;262 }263 264 /* Parse the node */265 ret = dt_to_map_one_config(p, pctldev, statename,266 np_config);267 of_node_put(np_config);268 if (ret < 0)269 goto err;270 }271 272 /* No entries in DT? Generate a dummy state table entry */273 if (!size) {274 ret = dt_remember_dummy_state(p, statename);275 if (ret < 0)276 goto err;277 }278 }279 280 return 0;281 282err:283 pinctrl_dt_free_maps(p);284 return ret;285}286 287/*288 * For pinctrl binding, typically #pinctrl-cells is for the pin controller289 * device, so either parent or grandparent. See pinctrl-bindings.txt.290 */291static int pinctrl_find_cells_size(const struct device_node *np)292{293 const char *cells_name = "#pinctrl-cells";294 int cells_size, error;295 296 error = of_property_read_u32(np->parent, cells_name, &cells_size);297 if (error) {298 error = of_property_read_u32(np->parent->parent,299 cells_name, &cells_size);300 if (error)301 return -ENOENT;302 }303 304 return cells_size;305}306 307/**308 * pinctrl_get_list_and_count - Gets the list and it's cell size and number309 * @np: pointer to device node with the property310 * @list_name: property that contains the list311 * @list: pointer for the list found312 * @cells_size: pointer for the cell size found313 * @nr_elements: pointer for the number of elements found314 *315 * Typically np is a single pinctrl entry containing the list.316 */317static int pinctrl_get_list_and_count(const struct device_node *np,318 const char *list_name,319 const __be32 **list,320 int *cells_size,321 int *nr_elements)322{323 int size;324 325 *cells_size = 0;326 *nr_elements = 0;327 328 *list = of_get_property(np, list_name, &size);329 if (!*list)330 return -ENOENT;331 332 *cells_size = pinctrl_find_cells_size(np);333 if (*cells_size < 0)334 return -ENOENT;335 336 /* First element is always the index within the pinctrl device */337 *nr_elements = (size / sizeof(**list)) / (*cells_size + 1);338 339 return 0;340}341 342/**343 * pinctrl_count_index_with_args - Count number of elements in a pinctrl entry344 * @np: pointer to device node with the property345 * @list_name: property that contains the list346 *347 * Counts the number of elements in a pinctrl array consisting of an index348 * within the controller and a number of u32 entries specified for each349 * entry. Note that device_node is always for the parent pin controller device.350 */351int pinctrl_count_index_with_args(const struct device_node *np,352 const char *list_name)353{354 const __be32 *list;355 int size, nr_cells, error;356 357 error = pinctrl_get_list_and_count(np, list_name, &list,358 &nr_cells, &size);359 if (error)360 return error;361 362 return size;363}364EXPORT_SYMBOL_GPL(pinctrl_count_index_with_args);365 366/**367 * pinctrl_copy_args - Populates of_phandle_args based on index368 * @np: pointer to device node with the property369 * @list: pointer to a list with the elements370 * @index: entry within the list of elements371 * @nr_cells: number of cells in the list372 * @nr_elem: number of elements for each entry in the list373 * @out_args: returned values374 *375 * Populates the of_phandle_args based on the index in the list.376 */377static int pinctrl_copy_args(const struct device_node *np,378 const __be32 *list,379 int index, int nr_cells, int nr_elem,380 struct of_phandle_args *out_args)381{382 int i;383 384 memset(out_args, 0, sizeof(*out_args));385 out_args->np = (struct device_node *)np;386 out_args->args_count = nr_cells + 1;387 388 if (index >= nr_elem)389 return -EINVAL;390 391 list += index * (nr_cells + 1);392 393 for (i = 0; i < nr_cells + 1; i++)394 out_args->args[i] = be32_to_cpup(list++);395 396 return 0;397}398 399/**400 * pinctrl_parse_index_with_args - Find a node pointed by index in a list401 * @np: pointer to device node with the property402 * @list_name: property that contains the list403 * @index: index within the list404 * @out_args: entries in the list pointed by index405 *406 * Finds the selected element in a pinctrl array consisting of an index407 * within the controller and a number of u32 entries specified for each408 * entry. Note that device_node is always for the parent pin controller device.409 */410int pinctrl_parse_index_with_args(const struct device_node *np,411 const char *list_name, int index,412 struct of_phandle_args *out_args)413{414 const __be32 *list;415 int nr_elem, nr_cells, error;416 417 error = pinctrl_get_list_and_count(np, list_name, &list,418 &nr_cells, &nr_elem);419 if (error || !nr_cells)420 return error;421 422 error = pinctrl_copy_args(np, list, index, nr_cells, nr_elem,423 out_args);424 if (error)425 return error;426 427 return 0;428}429EXPORT_SYMBOL_GPL(pinctrl_parse_index_with_args);430