1 // SPDX-License-Identifier: GPL-2.0-only
3 * Device tree integration for the pin control subsystem
5 * Copyright (C) 2012 NVIDIA CORPORATION. All rights reserved.
8 #include <linux/device.h>
10 #include <linux/pinctrl/pinctrl.h>
11 #include <linux/slab.h>
14 #include "devicetree.h"
17 * struct pinctrl_dt_map - mapping table chunk parsed from device tree
18 * @node: list node for struct pinctrl's @dt_maps field
19 * @pctldev: the pin controller that allocated this struct, and will free it
20 * @map: the mapping table entries
21 * @num_maps: number of mapping table entries
23 struct pinctrl_dt_map {
24 struct list_head node;
25 struct pinctrl_dev *pctldev;
26 struct pinctrl_map *map;
30 static void dt_free_map(struct pinctrl_dev *pctldev,
31 struct pinctrl_map *map, unsigned num_maps)
35 for (i = 0; i < num_maps; ++i) {
36 kfree_const(map[i].dev_name);
37 map[i].dev_name = NULL;
41 const struct pinctrl_ops *ops = pctldev->desc->pctlops;
43 ops->dt_free_map(pctldev, map, num_maps);
45 /* There is no pctldev for PIN_MAP_TYPE_DUMMY_STATE */
50 void pinctrl_dt_free_maps(struct pinctrl *p)
52 struct pinctrl_dt_map *dt_map, *n1;
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,
62 of_node_put(p->dev->of_node);
65 static int dt_remember_or_free_map(struct pinctrl *p, const char *statename,
66 struct pinctrl_dev *pctldev,
67 struct pinctrl_map *map, unsigned num_maps)
70 struct pinctrl_dt_map *dt_map;
72 /* Initialize common mapping table entry fields */
73 for (i = 0; i < num_maps; i++) {
76 devname = kstrdup_const(dev_name(p->dev), GFP_KERNEL);
80 map[i].dev_name = devname;
81 map[i].name = statename;
83 map[i].ctrl_dev_name = dev_name(pctldev->dev);
86 /* Remember the converted mapping table entries */
87 dt_map = kzalloc(sizeof(*dt_map), GFP_KERNEL);
91 dt_map->pctldev = pctldev;
93 dt_map->num_maps = num_maps;
94 list_add_tail(&dt_map->node, &p->dt_maps);
96 return pinctrl_register_mappings(map, num_maps);
99 dt_free_map(pctldev, map, num_maps);
103 struct pinctrl_dev *of_pinctrl_get(struct device_node *np)
105 return get_pinctrl_dev_from_of_node(np);
107 EXPORT_SYMBOL_GPL(of_pinctrl_get);
109 static 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)
114 struct pinctrl_dev *pctldev = NULL;
115 struct device_node *np_pctldev;
116 const struct pinctrl_ops *ops;
118 struct pinctrl_map *map;
120 bool allow_default = false;
122 /* Find the pin controller containing np_config */
123 np_pctldev = of_node_get(np_config);
126 allow_default = of_property_read_bool(np_pctldev,
127 "pinctrl-use-default");
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 = driver_deferred_probe_check_state(p->dev);
133 /* keep deferring if modules are enabled unless we've timed out */
134 if (IS_ENABLED(CONFIG_MODULES) && !allow_default &&
139 /* If we're creating a hog we can use the passed pctldev */
140 if (hog_pctldev && (np_pctldev == p->dev->of_node)) {
141 pctldev = hog_pctldev;
144 pctldev = get_pinctrl_dev_from_of_node(np_pctldev);
147 /* Do not defer probing of hogs (circular loop) */
148 if (np_pctldev == p->dev->of_node) {
149 of_node_put(np_pctldev);
153 of_node_put(np_pctldev);
156 * Call pinctrl driver to parse device tree node, and
157 * generate mapping table entries
159 ops = pctldev->desc->pctlops;
160 if (!ops->dt_node_to_map) {
161 dev_err(p->dev, "pctldev %s doesn't support DT\n",
162 dev_name(pctldev->dev));
165 ret = ops->dt_node_to_map(pctldev, np_config, &map, &num_maps);
168 else if (num_maps == 0) {
170 * If we have no valid maps (maybe caused by empty pinctrl node
171 * or typing error) ther is no need remember this, so just
175 "there is not valid maps for state %s\n", statename);
179 /* Stash the mapping table chunk away for later use */
180 return dt_remember_or_free_map(p, statename, pctldev, map, num_maps);
183 static int dt_remember_dummy_state(struct pinctrl *p, const char *statename)
185 struct pinctrl_map *map;
187 map = kzalloc(sizeof(*map), GFP_KERNEL);
191 /* There is no pctldev for PIN_MAP_TYPE_DUMMY_STATE */
192 map->type = PIN_MAP_TYPE_DUMMY_STATE;
194 return dt_remember_or_free_map(p, statename, NULL, map, 1);
197 int pinctrl_dt_to_map(struct pinctrl *p, struct pinctrl_dev *pctldev)
199 struct device_node *np = p->dev->of_node;
202 struct property *prop;
203 const char *statename;
207 struct device_node *np_config;
209 /* CONFIG_OF enabled, p->dev not instantiated from DT */
211 if (of_have_populated_dt())
213 "no of_node; not parsing pinctrl DT\n");
217 /* We may store pointers to property names within the node */
220 /* For each defined state ID */
221 for (state = 0; ; state++) {
222 /* Retrieve the pinctrl-* property */
223 propname = kasprintf(GFP_KERNEL, "pinctrl-%d", state);
224 prop = of_find_property(np, propname, &size);
234 size /= sizeof(*list);
236 /* Determine whether pinctrl-names property names the state */
237 ret = of_property_read_string_index(np, "pinctrl-names",
240 * If not, statename is just the integer state ID. But rather
241 * than dynamically allocate it and have to free it later,
242 * just point part way into the property name for the string.
245 statename = prop->name + strlen("pinctrl-");
247 /* For every referenced pin configuration node in it */
248 for (config = 0; config < size; config++) {
249 phandle = be32_to_cpup(list++);
251 /* Look up the pin configuration node */
252 np_config = of_find_node_by_phandle(phandle);
255 "prop %s index %i invalid phandle\n",
262 ret = dt_to_map_one_config(p, pctldev, statename,
264 of_node_put(np_config);
269 /* No entries in DT? Generate a dummy state table entry */
271 ret = dt_remember_dummy_state(p, statename);
280 pinctrl_dt_free_maps(p);
285 * For pinctrl binding, typically #pinctrl-cells is for the pin controller
286 * device, so either parent or grandparent. See pinctrl-bindings.txt.
288 static int pinctrl_find_cells_size(const struct device_node *np)
290 const char *cells_name = "#pinctrl-cells";
291 int cells_size, error;
293 error = of_property_read_u32(np->parent, cells_name, &cells_size);
295 error = of_property_read_u32(np->parent->parent,
296 cells_name, &cells_size);
305 * pinctrl_get_list_and_count - Gets the list and it's cell size and number
306 * @np: pointer to device node with the property
307 * @list_name: property that contains the list
308 * @list: pointer for the list found
309 * @cells_size: pointer for the cell size found
310 * @nr_elements: pointer for the number of elements found
312 * Typically np is a single pinctrl entry containing the list.
314 static int pinctrl_get_list_and_count(const struct device_node *np,
315 const char *list_name,
325 *list = of_get_property(np, list_name, &size);
329 *cells_size = pinctrl_find_cells_size(np);
333 /* First element is always the index within the pinctrl device */
334 *nr_elements = (size / sizeof(**list)) / (*cells_size + 1);
340 * pinctrl_count_index_with_args - Count number of elements in a pinctrl entry
341 * @np: pointer to device node with the property
342 * @list_name: property that contains the list
344 * Counts the number of elements in a pinctrl array consisting of an index
345 * within the controller and a number of u32 entries specified for each
346 * entry. Note that device_node is always for the parent pin controller device.
348 int pinctrl_count_index_with_args(const struct device_node *np,
349 const char *list_name)
352 int size, nr_cells, error;
354 error = pinctrl_get_list_and_count(np, list_name, &list,
361 EXPORT_SYMBOL_GPL(pinctrl_count_index_with_args);
364 * pinctrl_copy_args - Populates of_phandle_args based on index
365 * @np: pointer to device node with the property
366 * @list: pointer to a list with the elements
367 * @index: entry within the list of elements
368 * @nr_cells: number of cells in the list
369 * @nr_elem: number of elements for each entry in the list
370 * @out_args: returned values
372 * Populates the of_phandle_args based on the index in the list.
374 static int pinctrl_copy_args(const struct device_node *np,
376 int index, int nr_cells, int nr_elem,
377 struct of_phandle_args *out_args)
381 memset(out_args, 0, sizeof(*out_args));
382 out_args->np = (struct device_node *)np;
383 out_args->args_count = nr_cells + 1;
385 if (index >= nr_elem)
388 list += index * (nr_cells + 1);
390 for (i = 0; i < nr_cells + 1; i++)
391 out_args->args[i] = be32_to_cpup(list++);
397 * pinctrl_parse_index_with_args - Find a node pointed by index in a list
398 * @np: pointer to device node with the property
399 * @list_name: property that contains the list
400 * @index: index within the list
401 * @out_args: entries in the list pointed by index
403 * Finds the selected element in a pinctrl array consisting of an index
404 * within the controller and a number of u32 entries specified for each
405 * entry. Note that device_node is always for the parent pin controller device.
407 int pinctrl_parse_index_with_args(const struct device_node *np,
408 const char *list_name, int index,
409 struct of_phandle_args *out_args)
412 int nr_elem, nr_cells, error;
414 error = pinctrl_get_list_and_count(np, list_name, &list,
415 &nr_cells, &nr_elem);
416 if (error || !nr_cells)
419 error = pinctrl_copy_args(np, list, index, nr_cells, nr_elem,
426 EXPORT_SYMBOL_GPL(pinctrl_parse_index_with_args);