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 * @maps: the mapping table entries
22 struct pinctrl_dt_map {
23 struct list_head node;
24 struct pinctrl_dev *pctldev;
25 struct pinctrl_map *map;
29 static void dt_free_map(struct pinctrl_dev *pctldev,
30 struct pinctrl_map *map, unsigned num_maps)
33 const struct pinctrl_ops *ops = pctldev->desc->pctlops;
35 ops->dt_free_map(pctldev, map, num_maps);
37 /* There is no pctldev for PIN_MAP_TYPE_DUMMY_STATE */
42 void pinctrl_dt_free_maps(struct pinctrl *p)
44 struct pinctrl_dt_map *dt_map, *n1;
46 list_for_each_entry_safe(dt_map, n1, &p->dt_maps, node) {
47 pinctrl_unregister_map(dt_map->map);
48 list_del(&dt_map->node);
49 dt_free_map(dt_map->pctldev, dt_map->map,
54 of_node_put(p->dev->of_node);
57 static int dt_remember_or_free_map(struct pinctrl *p, const char *statename,
58 struct pinctrl_dev *pctldev,
59 struct pinctrl_map *map, unsigned num_maps)
62 struct pinctrl_dt_map *dt_map;
64 /* Initialize common mapping table entry fields */
65 for (i = 0; i < num_maps; i++) {
66 map[i].dev_name = dev_name(p->dev);
67 map[i].name = statename;
69 map[i].ctrl_dev_name = dev_name(pctldev->dev);
72 /* Remember the converted mapping table entries */
73 dt_map = kzalloc(sizeof(*dt_map), GFP_KERNEL);
75 dt_free_map(pctldev, map, num_maps);
79 dt_map->pctldev = pctldev;
81 dt_map->num_maps = num_maps;
82 list_add_tail(&dt_map->node, &p->dt_maps);
84 return pinctrl_register_map(map, num_maps, false);
87 struct pinctrl_dev *of_pinctrl_get(struct device_node *np)
89 return get_pinctrl_dev_from_of_node(np);
92 static int dt_to_map_one_config(struct pinctrl *p,
93 struct pinctrl_dev *hog_pctldev,
94 const char *statename,
95 struct device_node *np_config)
97 struct pinctrl_dev *pctldev = NULL;
98 struct device_node *np_pctldev;
99 const struct pinctrl_ops *ops;
101 struct pinctrl_map *map;
103 bool allow_default = false;
105 /* Find the pin controller containing np_config */
106 np_pctldev = of_node_get(np_config);
109 allow_default = of_property_read_bool(np_pctldev,
110 "pinctrl-use-default");
112 np_pctldev = of_get_next_parent(np_pctldev);
113 if (!np_pctldev || of_node_is_root(np_pctldev)) {
114 of_node_put(np_pctldev);
115 /* keep deferring if modules are enabled unless we've timed out */
116 if (IS_ENABLED(CONFIG_MODULES) && !allow_default)
117 return driver_deferred_probe_check_state_continue(p->dev);
119 return driver_deferred_probe_check_state(p->dev);
121 /* If we're creating a hog we can use the passed pctldev */
122 if (hog_pctldev && (np_pctldev == p->dev->of_node)) {
123 pctldev = hog_pctldev;
126 pctldev = get_pinctrl_dev_from_of_node(np_pctldev);
129 /* Do not defer probing of hogs (circular loop) */
130 if (np_pctldev == p->dev->of_node) {
131 of_node_put(np_pctldev);
135 of_node_put(np_pctldev);
138 * Call pinctrl driver to parse device tree node, and
139 * generate mapping table entries
141 ops = pctldev->desc->pctlops;
142 if (!ops->dt_node_to_map) {
143 dev_err(p->dev, "pctldev %s doesn't support DT\n",
144 dev_name(pctldev->dev));
147 ret = ops->dt_node_to_map(pctldev, np_config, &map, &num_maps);
151 /* Stash the mapping table chunk away for later use */
152 return dt_remember_or_free_map(p, statename, pctldev, map, num_maps);
155 static int dt_remember_dummy_state(struct pinctrl *p, const char *statename)
157 struct pinctrl_map *map;
159 map = kzalloc(sizeof(*map), GFP_KERNEL);
163 /* There is no pctldev for PIN_MAP_TYPE_DUMMY_STATE */
164 map->type = PIN_MAP_TYPE_DUMMY_STATE;
166 return dt_remember_or_free_map(p, statename, NULL, map, 1);
169 bool pinctrl_dt_has_hogs(struct pinctrl_dev *pctldev)
171 struct device_node *np;
172 struct property *prop;
175 np = pctldev->dev->of_node;
179 prop = of_find_property(np, "pinctrl-0", &size);
181 return prop ? true : false;
184 int pinctrl_dt_to_map(struct pinctrl *p, struct pinctrl_dev *pctldev)
186 struct device_node *np = p->dev->of_node;
189 struct property *prop;
190 const char *statename;
194 struct device_node *np_config;
196 /* CONFIG_OF enabled, p->dev not instantiated from DT */
198 if (of_have_populated_dt())
200 "no of_node; not parsing pinctrl DT\n");
204 /* We may store pointers to property names within the node */
207 /* For each defined state ID */
208 for (state = 0; ; state++) {
209 /* Retrieve the pinctrl-* property */
210 propname = kasprintf(GFP_KERNEL, "pinctrl-%d", state);
211 prop = of_find_property(np, propname, &size);
221 size /= sizeof(*list);
223 /* Determine whether pinctrl-names property names the state */
224 ret = of_property_read_string_index(np, "pinctrl-names",
227 * If not, statename is just the integer state ID. But rather
228 * than dynamically allocate it and have to free it later,
229 * just point part way into the property name for the string.
232 statename = prop->name + strlen("pinctrl-");
234 /* For every referenced pin configuration node in it */
235 for (config = 0; config < size; config++) {
236 phandle = be32_to_cpup(list++);
238 /* Look up the pin configuration node */
239 np_config = of_find_node_by_phandle(phandle);
242 "prop %s index %i invalid phandle\n",
249 ret = dt_to_map_one_config(p, pctldev, statename,
251 of_node_put(np_config);
256 /* No entries in DT? Generate a dummy state table entry */
258 ret = dt_remember_dummy_state(p, statename);
267 pinctrl_dt_free_maps(p);
272 * For pinctrl binding, typically #pinctrl-cells is for the pin controller
273 * device, so either parent or grandparent. See pinctrl-bindings.txt.
275 static int pinctrl_find_cells_size(const struct device_node *np)
277 const char *cells_name = "#pinctrl-cells";
278 int cells_size, error;
280 error = of_property_read_u32(np->parent, cells_name, &cells_size);
282 error = of_property_read_u32(np->parent->parent,
283 cells_name, &cells_size);
292 * pinctrl_get_list_and_count - Gets the list and it's cell size and number
293 * @np: pointer to device node with the property
294 * @list_name: property that contains the list
295 * @list: pointer for the list found
296 * @cells_size: pointer for the cell size found
297 * @nr_elements: pointer for the number of elements found
299 * Typically np is a single pinctrl entry containing the list.
301 static int pinctrl_get_list_and_count(const struct device_node *np,
302 const char *list_name,
312 *list = of_get_property(np, list_name, &size);
316 *cells_size = pinctrl_find_cells_size(np);
320 /* First element is always the index within the pinctrl device */
321 *nr_elements = (size / sizeof(**list)) / (*cells_size + 1);
327 * pinctrl_count_index_with_args - Count number of elements in a pinctrl entry
328 * @np: pointer to device node with the property
329 * @list_name: property that contains the list
331 * Counts the number of elements in a pinctrl array consisting of an index
332 * within the controller and a number of u32 entries specified for each
333 * entry. Note that device_node is always for the parent pin controller device.
335 int pinctrl_count_index_with_args(const struct device_node *np,
336 const char *list_name)
339 int size, nr_cells, error;
341 error = pinctrl_get_list_and_count(np, list_name, &list,
348 EXPORT_SYMBOL_GPL(pinctrl_count_index_with_args);
351 * pinctrl_copy_args - Populates of_phandle_args based on index
352 * @np: pointer to device node with the property
353 * @list: pointer to a list with the elements
354 * @index: entry within the list of elements
355 * @nr_cells: number of cells in the list
356 * @nr_elem: number of elements for each entry in the list
357 * @out_args: returned values
359 * Populates the of_phandle_args based on the index in the list.
361 static int pinctrl_copy_args(const struct device_node *np,
363 int index, int nr_cells, int nr_elem,
364 struct of_phandle_args *out_args)
368 memset(out_args, 0, sizeof(*out_args));
369 out_args->np = (struct device_node *)np;
370 out_args->args_count = nr_cells + 1;
372 if (index >= nr_elem)
375 list += index * (nr_cells + 1);
377 for (i = 0; i < nr_cells + 1; i++)
378 out_args->args[i] = be32_to_cpup(list++);
384 * pinctrl_parse_index_with_args - Find a node pointed by index in a list
385 * @np: pointer to device node with the property
386 * @list_name: property that contains the list
387 * @index: index within the list
388 * @out_arts: entries in the list pointed by index
390 * Finds the selected element in a pinctrl array consisting of an index
391 * within the controller and a number of u32 entries specified for each
392 * entry. Note that device_node is always for the parent pin controller device.
394 int pinctrl_parse_index_with_args(const struct device_node *np,
395 const char *list_name, int index,
396 struct of_phandle_args *out_args)
399 int nr_elem, nr_cells, error;
401 error = pinctrl_get_list_and_count(np, list_name, &list,
402 &nr_cells, &nr_elem);
403 if (error || !nr_cells)
406 error = pinctrl_copy_args(np, list, index, nr_cells, nr_elem,
413 EXPORT_SYMBOL_GPL(pinctrl_parse_index_with_args);