2 * Device tree integration for the pin control subsystem
4 * Copyright (C) 2012 NVIDIA CORPORATION. All rights reserved.
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2, as published by the Free Software Foundation.
10 * This program is distributed in the hope it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
15 * You should have received a copy of the GNU General Public License
16 * along with this program. If not, see <http://www.gnu.org/licenses/>.
19 #include <linux/device.h>
21 #include <linux/pinctrl/pinctrl.h>
22 #include <linux/slab.h>
25 #include "devicetree.h"
28 * struct pinctrl_dt_map - mapping table chunk parsed from device tree
29 * @node: list node for struct pinctrl's @dt_maps field
30 * @pctldev: the pin controller that allocated this struct, and will free it
31 * @maps: the mapping table entries
33 struct pinctrl_dt_map {
34 struct list_head node;
35 struct pinctrl_dev *pctldev;
36 struct pinctrl_map *map;
40 static void dt_free_map(struct pinctrl_dev *pctldev,
41 struct pinctrl_map *map, unsigned num_maps)
45 for (i = 0; i < num_maps; ++i) {
46 kfree_const(map[i].dev_name);
47 map[i].dev_name = NULL;
51 const struct pinctrl_ops *ops = pctldev->desc->pctlops;
53 ops->dt_free_map(pctldev, map, num_maps);
55 /* There is no pctldev for PIN_MAP_TYPE_DUMMY_STATE */
60 void pinctrl_dt_free_maps(struct pinctrl *p)
62 struct pinctrl_dt_map *dt_map, *n1;
64 list_for_each_entry_safe(dt_map, n1, &p->dt_maps, node) {
65 pinctrl_unregister_map(dt_map->map);
66 list_del(&dt_map->node);
67 dt_free_map(dt_map->pctldev, dt_map->map,
72 of_node_put(p->dev->of_node);
75 static int dt_remember_or_free_map(struct pinctrl *p, const char *statename,
76 struct pinctrl_dev *pctldev,
77 struct pinctrl_map *map, unsigned num_maps)
80 struct pinctrl_dt_map *dt_map;
82 /* Initialize common mapping table entry fields */
83 for (i = 0; i < num_maps; i++) {
86 devname = kstrdup_const(dev_name(p->dev), GFP_KERNEL);
90 map[i].dev_name = devname;
91 map[i].name = statename;
93 map[i].ctrl_dev_name = dev_name(pctldev->dev);
96 /* Remember the converted mapping table entries */
97 dt_map = kzalloc(sizeof(*dt_map), GFP_KERNEL);
101 dt_map->pctldev = pctldev;
103 dt_map->num_maps = num_maps;
104 list_add_tail(&dt_map->node, &p->dt_maps);
106 return pinctrl_register_map(map, num_maps, false);
109 dt_free_map(pctldev, map, num_maps);
113 struct pinctrl_dev *of_pinctrl_get(struct device_node *np)
115 return get_pinctrl_dev_from_of_node(np);
118 static int dt_to_map_one_config(struct pinctrl *p,
119 struct pinctrl_dev *hog_pctldev,
120 const char *statename,
121 struct device_node *np_config)
123 struct pinctrl_dev *pctldev = NULL;
124 struct device_node *np_pctldev;
125 const struct pinctrl_ops *ops;
127 struct pinctrl_map *map;
129 bool allow_default = false;
131 /* Find the pin controller containing np_config */
132 np_pctldev = of_node_get(np_config);
135 allow_default = of_property_read_bool(np_pctldev,
136 "pinctrl-use-default");
138 np_pctldev = of_get_next_parent(np_pctldev);
139 if (!np_pctldev || of_node_is_root(np_pctldev)) {
140 of_node_put(np_pctldev);
141 ret = driver_deferred_probe_check_state(p->dev);
142 /* keep deferring if modules are enabled unless we've timed out */
143 if (IS_ENABLED(CONFIG_MODULES) && !allow_default && ret == -ENODEV)
148 /* If we're creating a hog we can use the passed pctldev */
149 if (hog_pctldev && (np_pctldev == p->dev->of_node)) {
150 pctldev = hog_pctldev;
153 pctldev = get_pinctrl_dev_from_of_node(np_pctldev);
156 /* Do not defer probing of hogs (circular loop) */
157 if (np_pctldev == p->dev->of_node) {
158 of_node_put(np_pctldev);
162 of_node_put(np_pctldev);
165 * Call pinctrl driver to parse device tree node, and
166 * generate mapping table entries
168 ops = pctldev->desc->pctlops;
169 if (!ops->dt_node_to_map) {
170 dev_err(p->dev, "pctldev %s doesn't support DT\n",
171 dev_name(pctldev->dev));
174 ret = ops->dt_node_to_map(pctldev, np_config, &map, &num_maps);
178 /* Stash the mapping table chunk away for later use */
179 return dt_remember_or_free_map(p, statename, pctldev, map, num_maps);
182 static int dt_remember_dummy_state(struct pinctrl *p, const char *statename)
184 struct pinctrl_map *map;
186 map = kzalloc(sizeof(*map), GFP_KERNEL);
190 /* There is no pctldev for PIN_MAP_TYPE_DUMMY_STATE */
191 map->type = PIN_MAP_TYPE_DUMMY_STATE;
193 return dt_remember_or_free_map(p, statename, NULL, map, 1);
196 bool pinctrl_dt_has_hogs(struct pinctrl_dev *pctldev)
198 struct device_node *np;
199 struct property *prop;
202 np = pctldev->dev->of_node;
206 prop = of_find_property(np, "pinctrl-0", &size);
208 return prop ? true : false;
211 int pinctrl_dt_to_map(struct pinctrl *p, struct pinctrl_dev *pctldev)
213 struct device_node *np = p->dev->of_node;
216 struct property *prop;
217 const char *statename;
221 struct device_node *np_config;
223 /* CONFIG_OF enabled, p->dev not instantiated from DT */
225 if (of_have_populated_dt())
227 "no of_node; not parsing pinctrl DT\n");
231 /* We may store pointers to property names within the node */
234 /* For each defined state ID */
235 for (state = 0; ; state++) {
236 /* Retrieve the pinctrl-* property */
237 propname = kasprintf(GFP_KERNEL, "pinctrl-%d", state);
240 prop = of_find_property(np, propname, &size);
250 size /= sizeof(*list);
252 /* Determine whether pinctrl-names property names the state */
253 ret = of_property_read_string_index(np, "pinctrl-names",
256 * If not, statename is just the integer state ID. But rather
257 * than dynamically allocate it and have to free it later,
258 * just point part way into the property name for the string.
261 /* strlen("pinctrl-") == 8 */
262 statename = prop->name + 8;
265 /* For every referenced pin configuration node in it */
266 for (config = 0; config < size; config++) {
267 phandle = be32_to_cpup(list++);
269 /* Look up the pin configuration node */
270 np_config = of_find_node_by_phandle(phandle);
273 "prop %s index %i invalid phandle\n",
280 ret = dt_to_map_one_config(p, pctldev, statename,
282 of_node_put(np_config);
287 /* No entries in DT? Generate a dummy state table entry */
289 ret = dt_remember_dummy_state(p, statename);
298 pinctrl_dt_free_maps(p);
303 * For pinctrl binding, typically #pinctrl-cells is for the pin controller
304 * device, so either parent or grandparent. See pinctrl-bindings.txt.
306 static int pinctrl_find_cells_size(const struct device_node *np)
308 const char *cells_name = "#pinctrl-cells";
309 int cells_size, error;
311 error = of_property_read_u32(np->parent, cells_name, &cells_size);
313 error = of_property_read_u32(np->parent->parent,
314 cells_name, &cells_size);
323 * pinctrl_get_list_and_count - Gets the list and it's cell size and number
324 * @np: pointer to device node with the property
325 * @list_name: property that contains the list
326 * @list: pointer for the list found
327 * @cells_size: pointer for the cell size found
328 * @nr_elements: pointer for the number of elements found
330 * Typically np is a single pinctrl entry containing the list.
332 static int pinctrl_get_list_and_count(const struct device_node *np,
333 const char *list_name,
343 *list = of_get_property(np, list_name, &size);
347 *cells_size = pinctrl_find_cells_size(np);
351 /* First element is always the index within the pinctrl device */
352 *nr_elements = (size / sizeof(**list)) / (*cells_size + 1);
358 * pinctrl_count_index_with_args - Count number of elements in a pinctrl entry
359 * @np: pointer to device node with the property
360 * @list_name: property that contains the list
362 * Counts the number of elements in a pinctrl array consisting of an index
363 * within the controller and a number of u32 entries specified for each
364 * entry. Note that device_node is always for the parent pin controller device.
366 int pinctrl_count_index_with_args(const struct device_node *np,
367 const char *list_name)
370 int size, nr_cells, error;
372 error = pinctrl_get_list_and_count(np, list_name, &list,
379 EXPORT_SYMBOL_GPL(pinctrl_count_index_with_args);
382 * pinctrl_copy_args - Populates of_phandle_args based on index
383 * @np: pointer to device node with the property
384 * @list: pointer to a list with the elements
385 * @index: entry within the list of elements
386 * @nr_cells: number of cells in the list
387 * @nr_elem: number of elements for each entry in the list
388 * @out_args: returned values
390 * Populates the of_phandle_args based on the index in the list.
392 static int pinctrl_copy_args(const struct device_node *np,
394 int index, int nr_cells, int nr_elem,
395 struct of_phandle_args *out_args)
399 memset(out_args, 0, sizeof(*out_args));
400 out_args->np = (struct device_node *)np;
401 out_args->args_count = nr_cells + 1;
403 if (index >= nr_elem)
406 list += index * (nr_cells + 1);
408 for (i = 0; i < nr_cells + 1; i++)
409 out_args->args[i] = be32_to_cpup(list++);
415 * pinctrl_parse_index_with_args - Find a node pointed by index in a list
416 * @np: pointer to device node with the property
417 * @list_name: property that contains the list
418 * @index: index within the list
419 * @out_arts: entries in the list pointed by index
421 * Finds the selected element in a pinctrl array consisting of an index
422 * within the controller and a number of u32 entries specified for each
423 * entry. Note that device_node is always for the parent pin controller device.
425 int pinctrl_parse_index_with_args(const struct device_node *np,
426 const char *list_name, int index,
427 struct of_phandle_args *out_args)
430 int nr_elem, nr_cells, error;
432 error = pinctrl_get_list_and_count(np, list_name, &list,
433 &nr_cells, &nr_elem);
434 if (error || !nr_cells)
437 error = pinctrl_copy_args(np, list, index, nr_cells, nr_elem,
444 EXPORT_SYMBOL_GPL(pinctrl_parse_index_with_args);