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)
34 for (i = 0; i < num_maps; ++i) {
35 kfree_const(map[i].dev_name);
36 map[i].dev_name = NULL;
40 const struct pinctrl_ops *ops = pctldev->desc->pctlops;
42 ops->dt_free_map(pctldev, map, num_maps);
44 /* There is no pctldev for PIN_MAP_TYPE_DUMMY_STATE */
49 void pinctrl_dt_free_maps(struct pinctrl *p)
51 struct pinctrl_dt_map *dt_map, *n1;
53 list_for_each_entry_safe(dt_map, n1, &p->dt_maps, node) {
54 pinctrl_unregister_map(dt_map->map);
55 list_del(&dt_map->node);
56 dt_free_map(dt_map->pctldev, dt_map->map,
61 of_node_put(p->dev->of_node);
64 static int dt_remember_or_free_map(struct pinctrl *p, const char *statename,
65 struct pinctrl_dev *pctldev,
66 struct pinctrl_map *map, unsigned num_maps)
69 struct pinctrl_dt_map *dt_map;
71 /* Initialize common mapping table entry fields */
72 for (i = 0; i < num_maps; i++) {
75 devname = kstrdup_const(dev_name(p->dev), GFP_KERNEL);
79 map[i].dev_name = devname;
80 map[i].name = statename;
82 map[i].ctrl_dev_name = dev_name(pctldev->dev);
85 /* Remember the converted mapping table entries */
86 dt_map = kzalloc(sizeof(*dt_map), GFP_KERNEL);
90 dt_map->pctldev = pctldev;
92 dt_map->num_maps = num_maps;
93 list_add_tail(&dt_map->node, &p->dt_maps);
95 return pinctrl_register_map(map, num_maps, false);
98 dt_free_map(pctldev, map, num_maps);
102 struct pinctrl_dev *of_pinctrl_get(struct device_node *np)
104 return get_pinctrl_dev_from_of_node(np);
107 static int dt_to_map_one_config(struct pinctrl *p,
108 struct pinctrl_dev *hog_pctldev,
109 const char *statename,
110 struct device_node *np_config)
112 struct pinctrl_dev *pctldev = NULL;
113 struct device_node *np_pctldev;
114 const struct pinctrl_ops *ops;
116 struct pinctrl_map *map;
118 bool allow_default = false;
120 /* Find the pin controller containing np_config */
121 np_pctldev = of_node_get(np_config);
124 allow_default = of_property_read_bool(np_pctldev,
125 "pinctrl-use-default");
127 np_pctldev = of_get_next_parent(np_pctldev);
128 if (!np_pctldev || of_node_is_root(np_pctldev)) {
129 of_node_put(np_pctldev);
130 /* keep deferring if modules are enabled unless we've timed out */
131 if (IS_ENABLED(CONFIG_MODULES) && !allow_default)
132 return driver_deferred_probe_check_state_continue(p->dev);
134 return driver_deferred_probe_check_state(p->dev);
136 /* If we're creating a hog we can use the passed pctldev */
137 if (hog_pctldev && (np_pctldev == p->dev->of_node)) {
138 pctldev = hog_pctldev;
141 pctldev = get_pinctrl_dev_from_of_node(np_pctldev);
144 /* Do not defer probing of hogs (circular loop) */
145 if (np_pctldev == p->dev->of_node) {
146 of_node_put(np_pctldev);
150 of_node_put(np_pctldev);
153 * Call pinctrl driver to parse device tree node, and
154 * generate mapping table entries
156 ops = pctldev->desc->pctlops;
157 if (!ops->dt_node_to_map) {
158 dev_err(p->dev, "pctldev %s doesn't support DT\n",
159 dev_name(pctldev->dev));
162 ret = ops->dt_node_to_map(pctldev, np_config, &map, &num_maps);
166 /* Stash the mapping table chunk away for later use */
167 return dt_remember_or_free_map(p, statename, pctldev, map, num_maps);
170 static int dt_remember_dummy_state(struct pinctrl *p, const char *statename)
172 struct pinctrl_map *map;
174 map = kzalloc(sizeof(*map), GFP_KERNEL);
178 /* There is no pctldev for PIN_MAP_TYPE_DUMMY_STATE */
179 map->type = PIN_MAP_TYPE_DUMMY_STATE;
181 return dt_remember_or_free_map(p, statename, NULL, map, 1);
184 bool pinctrl_dt_has_hogs(struct pinctrl_dev *pctldev)
186 struct device_node *np;
187 struct property *prop;
190 np = pctldev->dev->of_node;
194 prop = of_find_property(np, "pinctrl-0", &size);
196 return prop ? true : false;
199 int pinctrl_dt_to_map(struct pinctrl *p, struct pinctrl_dev *pctldev)
201 struct device_node *np = p->dev->of_node;
204 struct property *prop;
205 const char *statename;
209 struct device_node *np_config;
211 /* CONFIG_OF enabled, p->dev not instantiated from DT */
213 if (of_have_populated_dt())
215 "no of_node; not parsing pinctrl DT\n");
219 /* We may store pointers to property names within the node */
222 /* For each defined state ID */
223 for (state = 0; ; state++) {
224 /* Retrieve the pinctrl-* property */
225 propname = kasprintf(GFP_KERNEL, "pinctrl-%d", state);
228 prop = of_find_property(np, propname, &size);
238 size /= sizeof(*list);
240 /* Determine whether pinctrl-names property names the state */
241 ret = of_property_read_string_index(np, "pinctrl-names",
244 * If not, statename is just the integer state ID. But rather
245 * than dynamically allocate it and have to free it later,
246 * just point part way into the property name for the string.
249 statename = prop->name + strlen("pinctrl-");
251 /* For every referenced pin configuration node in it */
252 for (config = 0; config < size; config++) {
253 phandle = be32_to_cpup(list++);
255 /* Look up the pin configuration node */
256 np_config = of_find_node_by_phandle(phandle);
259 "prop %s index %i invalid phandle\n",
266 ret = dt_to_map_one_config(p, pctldev, statename,
268 of_node_put(np_config);
273 /* No entries in DT? Generate a dummy state table entry */
275 ret = dt_remember_dummy_state(p, statename);
284 pinctrl_dt_free_maps(p);
289 * For pinctrl binding, typically #pinctrl-cells is for the pin controller
290 * device, so either parent or grandparent. See pinctrl-bindings.txt.
292 static int pinctrl_find_cells_size(const struct device_node *np)
294 const char *cells_name = "#pinctrl-cells";
295 int cells_size, error;
297 error = of_property_read_u32(np->parent, cells_name, &cells_size);
299 error = of_property_read_u32(np->parent->parent,
300 cells_name, &cells_size);
309 * pinctrl_get_list_and_count - Gets the list and it's cell size and number
310 * @np: pointer to device node with the property
311 * @list_name: property that contains the list
312 * @list: pointer for the list found
313 * @cells_size: pointer for the cell size found
314 * @nr_elements: pointer for the number of elements found
316 * Typically np is a single pinctrl entry containing the list.
318 static int pinctrl_get_list_and_count(const struct device_node *np,
319 const char *list_name,
329 *list = of_get_property(np, list_name, &size);
333 *cells_size = pinctrl_find_cells_size(np);
337 /* First element is always the index within the pinctrl device */
338 *nr_elements = (size / sizeof(**list)) / (*cells_size + 1);
344 * pinctrl_count_index_with_args - Count number of elements in a pinctrl entry
345 * @np: pointer to device node with the property
346 * @list_name: property that contains the list
348 * Counts the number of elements in a pinctrl array consisting of an index
349 * within the controller and a number of u32 entries specified for each
350 * entry. Note that device_node is always for the parent pin controller device.
352 int pinctrl_count_index_with_args(const struct device_node *np,
353 const char *list_name)
356 int size, nr_cells, error;
358 error = pinctrl_get_list_and_count(np, list_name, &list,
365 EXPORT_SYMBOL_GPL(pinctrl_count_index_with_args);
368 * pinctrl_copy_args - Populates of_phandle_args based on index
369 * @np: pointer to device node with the property
370 * @list: pointer to a list with the elements
371 * @index: entry within the list of elements
372 * @nr_cells: number of cells in the list
373 * @nr_elem: number of elements for each entry in the list
374 * @out_args: returned values
376 * Populates the of_phandle_args based on the index in the list.
378 static int pinctrl_copy_args(const struct device_node *np,
380 int index, int nr_cells, int nr_elem,
381 struct of_phandle_args *out_args)
385 memset(out_args, 0, sizeof(*out_args));
386 out_args->np = (struct device_node *)np;
387 out_args->args_count = nr_cells + 1;
389 if (index >= nr_elem)
392 list += index * (nr_cells + 1);
394 for (i = 0; i < nr_cells + 1; i++)
395 out_args->args[i] = be32_to_cpup(list++);
401 * pinctrl_parse_index_with_args - Find a node pointed by index in a list
402 * @np: pointer to device node with the property
403 * @list_name: property that contains the list
404 * @index: index within the list
405 * @out_arts: entries in the list pointed by index
407 * Finds the selected element in a pinctrl array consisting of an index
408 * within the controller and a number of u32 entries specified for each
409 * entry. Note that device_node is always for the parent pin controller device.
411 int pinctrl_parse_index_with_args(const struct device_node *np,
412 const char *list_name, int index,
413 struct of_phandle_args *out_args)
416 int nr_elem, nr_cells, error;
418 error = pinctrl_get_list_and_count(np, list_name, &list,
419 &nr_cells, &nr_elem);
420 if (error || !nr_cells)
423 error = pinctrl_copy_args(np, list, index, nr_cells, nr_elem,
430 EXPORT_SYMBOL_GPL(pinctrl_parse_index_with_args);