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;
130 /* Find the pin controller containing np_config */
131 np_pctldev = of_node_get(np_config);
133 np_pctldev = of_get_next_parent(np_pctldev);
134 if (!np_pctldev || of_node_is_root(np_pctldev)) {
135 dev_info(p->dev, "could not find pctldev for node %pOF, deferring probe\n",
137 of_node_put(np_pctldev);
138 /* OK let's just assume this will appear later then */
139 return -EPROBE_DEFER;
141 /* If we're creating a hog we can use the passed pctldev */
142 if (hog_pctldev && (np_pctldev == p->dev->of_node)) {
143 pctldev = hog_pctldev;
146 pctldev = get_pinctrl_dev_from_of_node(np_pctldev);
149 /* Do not defer probing of hogs (circular loop) */
150 if (np_pctldev == p->dev->of_node) {
151 of_node_put(np_pctldev);
155 of_node_put(np_pctldev);
158 * Call pinctrl driver to parse device tree node, and
159 * generate mapping table entries
161 ops = pctldev->desc->pctlops;
162 if (!ops->dt_node_to_map) {
163 dev_err(p->dev, "pctldev %s doesn't support DT\n",
164 dev_name(pctldev->dev));
167 ret = ops->dt_node_to_map(pctldev, np_config, &map, &num_maps);
171 /* Stash the mapping table chunk away for later use */
172 return dt_remember_or_free_map(p, statename, pctldev, map, num_maps);
175 static int dt_remember_dummy_state(struct pinctrl *p, const char *statename)
177 struct pinctrl_map *map;
179 map = kzalloc(sizeof(*map), GFP_KERNEL);
183 /* There is no pctldev for PIN_MAP_TYPE_DUMMY_STATE */
184 map->type = PIN_MAP_TYPE_DUMMY_STATE;
186 return dt_remember_or_free_map(p, statename, NULL, map, 1);
189 bool pinctrl_dt_has_hogs(struct pinctrl_dev *pctldev)
191 struct device_node *np;
192 struct property *prop;
195 np = pctldev->dev->of_node;
199 prop = of_find_property(np, "pinctrl-0", &size);
201 return prop ? true : false;
204 int pinctrl_dt_to_map(struct pinctrl *p, struct pinctrl_dev *pctldev)
206 struct device_node *np = p->dev->of_node;
209 struct property *prop;
210 const char *statename;
214 struct device_node *np_config;
216 /* CONFIG_OF enabled, p->dev not instantiated from DT */
218 if (of_have_populated_dt())
220 "no of_node; not parsing pinctrl DT\n");
224 /* We may store pointers to property names within the node */
227 /* For each defined state ID */
228 for (state = 0; ; state++) {
229 /* Retrieve the pinctrl-* property */
230 propname = kasprintf(GFP_KERNEL, "pinctrl-%d", state);
233 prop = of_find_property(np, propname, &size);
243 size /= sizeof(*list);
245 /* Determine whether pinctrl-names property names the state */
246 ret = of_property_read_string_index(np, "pinctrl-names",
249 * If not, statename is just the integer state ID. But rather
250 * than dynamically allocate it and have to free it later,
251 * just point part way into the property name for the string.
254 /* strlen("pinctrl-") == 8 */
255 statename = prop->name + 8;
258 /* For every referenced pin configuration node in it */
259 for (config = 0; config < size; config++) {
260 phandle = be32_to_cpup(list++);
262 /* Look up the pin configuration node */
263 np_config = of_find_node_by_phandle(phandle);
266 "prop %s index %i invalid phandle\n",
273 ret = dt_to_map_one_config(p, pctldev, statename,
275 of_node_put(np_config);
280 /* No entries in DT? Generate a dummy state table entry */
282 ret = dt_remember_dummy_state(p, statename);
291 pinctrl_dt_free_maps(p);
296 * For pinctrl binding, typically #pinctrl-cells is for the pin controller
297 * device, so either parent or grandparent. See pinctrl-bindings.txt.
299 static int pinctrl_find_cells_size(const struct device_node *np)
301 const char *cells_name = "#pinctrl-cells";
302 int cells_size, error;
304 error = of_property_read_u32(np->parent, cells_name, &cells_size);
306 error = of_property_read_u32(np->parent->parent,
307 cells_name, &cells_size);
316 * pinctrl_get_list_and_count - Gets the list and it's cell size and number
317 * @np: pointer to device node with the property
318 * @list_name: property that contains the list
319 * @list: pointer for the list found
320 * @cells_size: pointer for the cell size found
321 * @nr_elements: pointer for the number of elements found
323 * Typically np is a single pinctrl entry containing the list.
325 static int pinctrl_get_list_and_count(const struct device_node *np,
326 const char *list_name,
336 *list = of_get_property(np, list_name, &size);
340 *cells_size = pinctrl_find_cells_size(np);
344 /* First element is always the index within the pinctrl device */
345 *nr_elements = (size / sizeof(**list)) / (*cells_size + 1);
351 * pinctrl_count_index_with_args - Count number of elements in a pinctrl entry
352 * @np: pointer to device node with the property
353 * @list_name: property that contains the list
355 * Counts the number of elements in a pinctrl array consisting of an index
356 * within the controller and a number of u32 entries specified for each
357 * entry. Note that device_node is always for the parent pin controller device.
359 int pinctrl_count_index_with_args(const struct device_node *np,
360 const char *list_name)
363 int size, nr_cells, error;
365 error = pinctrl_get_list_and_count(np, list_name, &list,
372 EXPORT_SYMBOL_GPL(pinctrl_count_index_with_args);
375 * pinctrl_copy_args - Populates of_phandle_args based on index
376 * @np: pointer to device node with the property
377 * @list: pointer to a list with the elements
378 * @index: entry within the list of elements
379 * @nr_cells: number of cells in the list
380 * @nr_elem: number of elements for each entry in the list
381 * @out_args: returned values
383 * Populates the of_phandle_args based on the index in the list.
385 static int pinctrl_copy_args(const struct device_node *np,
387 int index, int nr_cells, int nr_elem,
388 struct of_phandle_args *out_args)
392 memset(out_args, 0, sizeof(*out_args));
393 out_args->np = (struct device_node *)np;
394 out_args->args_count = nr_cells + 1;
396 if (index >= nr_elem)
399 list += index * (nr_cells + 1);
401 for (i = 0; i < nr_cells + 1; i++)
402 out_args->args[i] = be32_to_cpup(list++);
408 * pinctrl_parse_index_with_args - Find a node pointed by index in a list
409 * @np: pointer to device node with the property
410 * @list_name: property that contains the list
411 * @index: index within the list
412 * @out_arts: entries in the list pointed by index
414 * Finds the selected element in a pinctrl array consisting of an index
415 * within the controller and a number of u32 entries specified for each
416 * entry. Note that device_node is always for the parent pin controller device.
418 int pinctrl_parse_index_with_args(const struct device_node *np,
419 const char *list_name, int index,
420 struct of_phandle_args *out_args)
423 int nr_elem, nr_cells, error;
425 error = pinctrl_get_list_and_count(np, list_name, &list,
426 &nr_cells, &nr_elem);
427 if (error || !nr_cells)
430 error = pinctrl_copy_args(np, list, index, nr_cells, nr_elem,
437 EXPORT_SYMBOL_GPL(pinctrl_parse_index_with_args);