blob: fe04e748dfe4b5cf036af6e9e2af7ba7c0868b19 [file] [log] [blame]
Stephen Warren57291ce2012-03-23 10:29:46 -06001/*
2 * Device tree integration for the pin control subsystem
3 *
4 * Copyright (C) 2012 NVIDIA CORPORATION. All rights reserved.
5 *
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.
9 *
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
13 * more details.
14 *
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/>.
17 */
18
19#include <linux/device.h>
20#include <linux/of.h>
21#include <linux/pinctrl/pinctrl.h>
22#include <linux/slab.h>
23
24#include "core.h"
25#include "devicetree.h"
26
27/**
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
32 */
33struct pinctrl_dt_map {
34 struct list_head node;
35 struct pinctrl_dev *pctldev;
36 struct pinctrl_map *map;
37 unsigned num_maps;
38};
39
40static void dt_free_map(struct pinctrl_dev *pctldev,
41 struct pinctrl_map *map, unsigned num_maps)
42{
43 if (pctldev) {
Laurent Pinchart022ab142013-02-16 10:25:07 +010044 const struct pinctrl_ops *ops = pctldev->desc->pctlops;
Stephen Warren57291ce2012-03-23 10:29:46 -060045 ops->dt_free_map(pctldev, map, num_maps);
46 } else {
47 /* There is no pctldev for PIN_MAP_TYPE_DUMMY_STATE */
48 kfree(map);
49 }
50}
51
52void pinctrl_dt_free_maps(struct pinctrl *p)
53{
54 struct pinctrl_dt_map *dt_map, *n1;
55
56 list_for_each_entry_safe(dt_map, n1, &p->dt_maps, node) {
57 pinctrl_unregister_map(dt_map->map);
58 list_del(&dt_map->node);
59 dt_free_map(dt_map->pctldev, dt_map->map,
60 dt_map->num_maps);
61 kfree(dt_map);
62 }
63
64 of_node_put(p->dev->of_node);
65}
66
67static int dt_remember_or_free_map(struct pinctrl *p, const char *statename,
68 struct pinctrl_dev *pctldev,
69 struct pinctrl_map *map, unsigned num_maps)
70{
71 int i;
72 struct pinctrl_dt_map *dt_map;
73
74 /* Initialize common mapping table entry fields */
75 for (i = 0; i < num_maps; i++) {
76 map[i].dev_name = dev_name(p->dev);
77 map[i].name = statename;
78 if (pctldev)
79 map[i].ctrl_dev_name = dev_name(pctldev->dev);
80 }
81
82 /* Remember the converted mapping table entries */
83 dt_map = kzalloc(sizeof(*dt_map), GFP_KERNEL);
84 if (!dt_map) {
85 dev_err(p->dev, "failed to alloc struct pinctrl_dt_map\n");
86 dt_free_map(pctldev, map, num_maps);
87 return -ENOMEM;
88 }
89
90 dt_map->pctldev = pctldev;
91 dt_map->map = map;
92 dt_map->num_maps = num_maps;
93 list_add_tail(&dt_map->node, &p->dt_maps);
94
Doug Andersonc5272a22015-05-01 09:01:27 -070095 return pinctrl_register_map(map, num_maps, false);
Stephen Warren57291ce2012-03-23 10:29:46 -060096}
97
Linus Walleij1e63d7b2012-11-06 16:03:35 +010098struct pinctrl_dev *of_pinctrl_get(struct device_node *np)
Shiraz Hashimf23f1512012-10-27 15:21:36 +053099{
Masahiro Yamadafb00de72015-06-18 14:42:45 +0900100 return get_pinctrl_dev_from_of_node(np);
Shiraz Hashimf23f1512012-10-27 15:21:36 +0530101}
102
Stephen Warren57291ce2012-03-23 10:29:46 -0600103static int dt_to_map_one_config(struct pinctrl *p, const char *statename,
104 struct device_node *np_config)
105{
106 struct device_node *np_pctldev;
107 struct pinctrl_dev *pctldev;
Laurent Pinchart022ab142013-02-16 10:25:07 +0100108 const struct pinctrl_ops *ops;
Stephen Warren57291ce2012-03-23 10:29:46 -0600109 int ret;
110 struct pinctrl_map *map;
111 unsigned num_maps;
112
113 /* Find the pin controller containing np_config */
114 np_pctldev = of_node_get(np_config);
115 for (;;) {
116 np_pctldev = of_get_next_parent(np_pctldev);
117 if (!np_pctldev || of_node_is_root(np_pctldev)) {
Linus Walleijc05127c2012-04-10 10:00:38 +0200118 dev_info(p->dev, "could not find pctldev for node %s, deferring probe\n",
Stephen Warren57291ce2012-03-23 10:29:46 -0600119 np_config->full_name);
120 of_node_put(np_pctldev);
Linus Walleijc05127c2012-04-10 10:00:38 +0200121 /* OK let's just assume this will appear later then */
122 return -EPROBE_DEFER;
Stephen Warren57291ce2012-03-23 10:29:46 -0600123 }
Patrice Chotard42fed7b2013-04-11 11:01:27 +0200124 pctldev = get_pinctrl_dev_from_of_node(np_pctldev);
Stephen Warren57291ce2012-03-23 10:29:46 -0600125 if (pctldev)
126 break;
Linus Walleijb2083062013-01-11 21:22:36 +0100127 /* Do not defer probing of hogs (circular loop) */
128 if (np_pctldev == p->dev->of_node) {
129 of_node_put(np_pctldev);
130 return -ENODEV;
131 }
Stephen Warren57291ce2012-03-23 10:29:46 -0600132 }
133 of_node_put(np_pctldev);
134
135 /*
136 * Call pinctrl driver to parse device tree node, and
137 * generate mapping table entries
138 */
139 ops = pctldev->desc->pctlops;
140 if (!ops->dt_node_to_map) {
141 dev_err(p->dev, "pctldev %s doesn't support DT\n",
142 dev_name(pctldev->dev));
143 return -ENODEV;
144 }
145 ret = ops->dt_node_to_map(pctldev, np_config, &map, &num_maps);
146 if (ret < 0)
147 return ret;
148
149 /* Stash the mapping table chunk away for later use */
150 return dt_remember_or_free_map(p, statename, pctldev, map, num_maps);
151}
152
153static int dt_remember_dummy_state(struct pinctrl *p, const char *statename)
154{
155 struct pinctrl_map *map;
156
157 map = kzalloc(sizeof(*map), GFP_KERNEL);
158 if (!map) {
159 dev_err(p->dev, "failed to alloc struct pinctrl_map\n");
160 return -ENOMEM;
161 }
162
163 /* There is no pctldev for PIN_MAP_TYPE_DUMMY_STATE */
164 map->type = PIN_MAP_TYPE_DUMMY_STATE;
165
166 return dt_remember_or_free_map(p, statename, NULL, map, 1);
167}
168
169int pinctrl_dt_to_map(struct pinctrl *p)
170{
171 struct device_node *np = p->dev->of_node;
172 int state, ret;
173 char *propname;
174 struct property *prop;
175 const char *statename;
176 const __be32 *list;
177 int size, config;
178 phandle phandle;
179 struct device_node *np_config;
180
181 /* CONFIG_OF enabled, p->dev not instantiated from DT */
182 if (!np) {
Mark Brown5d88dce2014-01-30 18:57:20 +0000183 if (of_have_populated_dt())
184 dev_dbg(p->dev,
185 "no of_node; not parsing pinctrl DT\n");
Stephen Warren57291ce2012-03-23 10:29:46 -0600186 return 0;
187 }
188
189 /* We may store pointers to property names within the node */
190 of_node_get(np);
191
192 /* For each defined state ID */
193 for (state = 0; ; state++) {
194 /* Retrieve the pinctrl-* property */
195 propname = kasprintf(GFP_KERNEL, "pinctrl-%d", state);
196 prop = of_find_property(np, propname, &size);
197 kfree(propname);
198 if (!prop)
199 break;
200 list = prop->value;
201 size /= sizeof(*list);
202
203 /* Determine whether pinctrl-names property names the state */
204 ret = of_property_read_string_index(np, "pinctrl-names",
205 state, &statename);
206 /*
207 * If not, statename is just the integer state ID. But rather
208 * than dynamically allocate it and have to free it later,
209 * just point part way into the property name for the string.
210 */
211 if (ret < 0) {
212 /* strlen("pinctrl-") == 8 */
213 statename = prop->name + 8;
214 }
215
216 /* For every referenced pin configuration node in it */
217 for (config = 0; config < size; config++) {
218 phandle = be32_to_cpup(list++);
219
220 /* Look up the pin configuration node */
221 np_config = of_find_node_by_phandle(phandle);
222 if (!np_config) {
223 dev_err(p->dev,
224 "prop %s index %i invalid phandle\n",
225 prop->name, config);
226 ret = -EINVAL;
227 goto err;
228 }
229
230 /* Parse the node */
231 ret = dt_to_map_one_config(p, statename, np_config);
232 of_node_put(np_config);
233 if (ret < 0)
234 goto err;
235 }
236
237 /* No entries in DT? Generate a dummy state table entry */
238 if (!size) {
239 ret = dt_remember_dummy_state(p, statename);
240 if (ret < 0)
241 goto err;
242 }
243 }
244
245 return 0;
246
247err:
248 pinctrl_dt_free_maps(p);
249 return ret;
250}