1 /*
2 * OF helpers for regulator framework
3 *
4 * Copyright (C) 2011 Texas Instruments, Inc.
5 * Rajendra Nayak <rnayak@ti.com>
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 */
12
13 #include <linux/module.h>
14 #include <linux/slab.h>
15 #include <linux/of.h>
16 #include <linux/regulator/machine.h>
17 #include <linux/regulator/driver.h>
18 #include <linux/regulator/of_regulator.h>
19
20 #include "internal.h"
21
22 static const char *const regulator_states[PM_SUSPEND_MAX + 1] = {
23 [PM_SUSPEND_MEM] = "regulator-state-mem",
24 [PM_SUSPEND_MAX] = "regulator-state-disk",
25 };
26
of_get_regulation_constraints(struct device_node * np,struct regulator_init_data ** init_data,const struct regulator_desc * desc)27 static void of_get_regulation_constraints(struct device_node *np,
28 struct regulator_init_data **init_data,
29 const struct regulator_desc *desc)
30 {
31 struct regulation_constraints *constraints = &(*init_data)->constraints;
32 struct regulator_state *suspend_state;
33 struct device_node *suspend_np;
34 unsigned int mode;
35 int ret, i;
36 u32 pval;
37
38 constraints->name = of_get_property(np, "regulator-name", NULL);
39
40 if (!of_property_read_u32(np, "regulator-min-microvolt", &pval))
41 constraints->min_uV = pval;
42
43 if (!of_property_read_u32(np, "regulator-max-microvolt", &pval))
44 constraints->max_uV = pval;
45
46 /* Voltage change possible? */
47 if (constraints->min_uV != constraints->max_uV)
48 constraints->valid_ops_mask |= REGULATOR_CHANGE_VOLTAGE;
49
50 /* Do we have a voltage range, if so try to apply it? */
51 if (constraints->min_uV && constraints->max_uV)
52 constraints->apply_uV = true;
53
54 if (!of_property_read_u32(np, "regulator-microvolt-offset", &pval))
55 constraints->uV_offset = pval;
56 if (!of_property_read_u32(np, "regulator-min-microamp", &pval))
57 constraints->min_uA = pval;
58 if (!of_property_read_u32(np, "regulator-max-microamp", &pval))
59 constraints->max_uA = pval;
60
61 if (!of_property_read_u32(np, "regulator-input-current-limit-microamp",
62 &pval))
63 constraints->ilim_uA = pval;
64
65 /* Current change possible? */
66 if (constraints->min_uA != constraints->max_uA)
67 constraints->valid_ops_mask |= REGULATOR_CHANGE_CURRENT;
68
69 constraints->boot_on = of_property_read_bool(np, "regulator-boot-on");
70 constraints->always_on = of_property_read_bool(np, "regulator-always-on");
71 if (!constraints->always_on) /* status change should be possible. */
72 constraints->valid_ops_mask |= REGULATOR_CHANGE_STATUS;
73
74 constraints->pull_down = of_property_read_bool(np, "regulator-pull-down");
75
76 if (of_property_read_bool(np, "regulator-allow-bypass"))
77 constraints->valid_ops_mask |= REGULATOR_CHANGE_BYPASS;
78
79 if (of_property_read_bool(np, "regulator-allow-set-load"))
80 constraints->valid_ops_mask |= REGULATOR_CHANGE_DRMS;
81
82 ret = of_property_read_u32(np, "regulator-ramp-delay", &pval);
83 if (!ret) {
84 if (pval)
85 constraints->ramp_delay = pval;
86 else
87 constraints->ramp_disable = true;
88 }
89
90 ret = of_property_read_u32(np, "regulator-settling-time-us", &pval);
91 if (!ret)
92 constraints->settling_time = pval;
93
94 ret = of_property_read_u32(np, "regulator-settling-time-up-us", &pval);
95 if (!ret)
96 constraints->settling_time_up = pval;
97 if (constraints->settling_time_up && constraints->settling_time) {
98 pr_warn("%s: ambiguous configuration for settling time, ignoring 'regulator-settling-time-up-us'\n",
99 np->name);
100 constraints->settling_time_up = 0;
101 }
102
103 ret = of_property_read_u32(np, "regulator-settling-time-down-us",
104 &pval);
105 if (!ret)
106 constraints->settling_time_down = pval;
107 if (constraints->settling_time_down && constraints->settling_time) {
108 pr_warn("%s: ambiguous configuration for settling time, ignoring 'regulator-settling-time-down-us'\n",
109 np->name);
110 constraints->settling_time_down = 0;
111 }
112
113 ret = of_property_read_u32(np, "regulator-enable-ramp-delay", &pval);
114 if (!ret)
115 constraints->enable_time = pval;
116
117 constraints->soft_start = of_property_read_bool(np,
118 "regulator-soft-start");
119 ret = of_property_read_u32(np, "regulator-active-discharge", &pval);
120 if (!ret) {
121 constraints->active_discharge =
122 (pval) ? REGULATOR_ACTIVE_DISCHARGE_ENABLE :
123 REGULATOR_ACTIVE_DISCHARGE_DISABLE;
124 }
125
126 if (!of_property_read_u32(np, "regulator-initial-mode", &pval)) {
127 if (desc && desc->of_map_mode) {
128 mode = desc->of_map_mode(pval);
129 if (mode == REGULATOR_MODE_INVALID)
130 pr_err("%s: invalid mode %u\n", np->name, pval);
131 else
132 constraints->initial_mode = mode;
133 } else {
134 pr_warn("%s: mapping for mode %d not defined\n",
135 np->name, pval);
136 }
137 }
138
139 if (!of_property_read_u32(np, "regulator-system-load", &pval))
140 constraints->system_load = pval;
141
142 constraints->over_current_protection = of_property_read_bool(np,
143 "regulator-over-current-protection");
144
145 for (i = 0; i < ARRAY_SIZE(regulator_states); i++) {
146 switch (i) {
147 case PM_SUSPEND_MEM:
148 suspend_state = &constraints->state_mem;
149 break;
150 case PM_SUSPEND_MAX:
151 suspend_state = &constraints->state_disk;
152 break;
153 case PM_SUSPEND_ON:
154 case PM_SUSPEND_TO_IDLE:
155 case PM_SUSPEND_STANDBY:
156 default:
157 continue;
158 }
159
160 suspend_np = of_get_child_by_name(np, regulator_states[i]);
161 if (!suspend_np || !suspend_state)
162 continue;
163
164 if (!of_property_read_u32(suspend_np, "regulator-mode",
165 &pval)) {
166 if (desc && desc->of_map_mode) {
167 mode = desc->of_map_mode(pval);
168 if (mode == REGULATOR_MODE_INVALID)
169 pr_err("%s: invalid mode %u\n",
170 np->name, pval);
171 else
172 suspend_state->mode = mode;
173 } else {
174 pr_warn("%s: mapping for mode %d not defined\n",
175 np->name, pval);
176 }
177 }
178
179 if (of_property_read_bool(suspend_np,
180 "regulator-on-in-suspend"))
181 suspend_state->enabled = true;
182 else if (of_property_read_bool(suspend_np,
183 "regulator-off-in-suspend"))
184 suspend_state->disabled = true;
185
186 if (!of_property_read_u32(suspend_np,
187 "regulator-suspend-microvolt", &pval))
188 suspend_state->uV = pval;
189
190 if (i == PM_SUSPEND_MEM)
191 constraints->initial_state = PM_SUSPEND_MEM;
192
193 of_node_put(suspend_np);
194 suspend_state = NULL;
195 suspend_np = NULL;
196 }
197 }
198
199 /**
200 * of_get_regulator_init_data - extract regulator_init_data structure info
201 * @dev: device requesting for regulator_init_data
202 * @node: regulator device node
203 * @desc: regulator description
204 *
205 * Populates regulator_init_data structure by extracting data from device
206 * tree node, returns a pointer to the populated struture or NULL if memory
207 * alloc fails.
208 */
of_get_regulator_init_data(struct device * dev,struct device_node * node,const struct regulator_desc * desc)209 struct regulator_init_data *of_get_regulator_init_data(struct device *dev,
210 struct device_node *node,
211 const struct regulator_desc *desc)
212 {
213 struct regulator_init_data *init_data;
214
215 if (!node)
216 return NULL;
217
218 init_data = devm_kzalloc(dev, sizeof(*init_data), GFP_KERNEL);
219 if (!init_data)
220 return NULL; /* Out of memory? */
221
222 of_get_regulation_constraints(node, &init_data, desc);
223 return init_data;
224 }
225 EXPORT_SYMBOL_GPL(of_get_regulator_init_data);
226
227 struct devm_of_regulator_matches {
228 struct of_regulator_match *matches;
229 unsigned int num_matches;
230 };
231
devm_of_regulator_put_matches(struct device * dev,void * res)232 static void devm_of_regulator_put_matches(struct device *dev, void *res)
233 {
234 struct devm_of_regulator_matches *devm_matches = res;
235 int i;
236
237 for (i = 0; i < devm_matches->num_matches; i++)
238 of_node_put(devm_matches->matches[i].of_node);
239 }
240
241 /**
242 * of_regulator_match - extract multiple regulator init data from device tree.
243 * @dev: device requesting the data
244 * @node: parent device node of the regulators
245 * @matches: match table for the regulators
246 * @num_matches: number of entries in match table
247 *
248 * This function uses a match table specified by the regulator driver to
249 * parse regulator init data from the device tree. @node is expected to
250 * contain a set of child nodes, each providing the init data for one
251 * regulator. The data parsed from a child node will be matched to a regulator
252 * based on either the deprecated property regulator-compatible if present,
253 * or otherwise the child node's name. Note that the match table is modified
254 * in place and an additional of_node reference is taken for each matched
255 * regulator.
256 *
257 * Returns the number of matches found or a negative error code on failure.
258 */
of_regulator_match(struct device * dev,struct device_node * node,struct of_regulator_match * matches,unsigned int num_matches)259 int of_regulator_match(struct device *dev, struct device_node *node,
260 struct of_regulator_match *matches,
261 unsigned int num_matches)
262 {
263 unsigned int count = 0;
264 unsigned int i;
265 const char *name;
266 struct device_node *child;
267 struct devm_of_regulator_matches *devm_matches;
268
269 if (!dev || !node)
270 return -EINVAL;
271
272 devm_matches = devres_alloc(devm_of_regulator_put_matches,
273 sizeof(struct devm_of_regulator_matches),
274 GFP_KERNEL);
275 if (!devm_matches)
276 return -ENOMEM;
277
278 devm_matches->matches = matches;
279 devm_matches->num_matches = num_matches;
280
281 devres_add(dev, devm_matches);
282
283 for (i = 0; i < num_matches; i++) {
284 struct of_regulator_match *match = &matches[i];
285 match->init_data = NULL;
286 match->of_node = NULL;
287 }
288
289 for_each_child_of_node(node, child) {
290 name = of_get_property(child,
291 "regulator-compatible", NULL);
292 if (!name)
293 name = child->name;
294 for (i = 0; i < num_matches; i++) {
295 struct of_regulator_match *match = &matches[i];
296 if (match->of_node)
297 continue;
298
299 if (strcmp(match->name, name))
300 continue;
301
302 match->init_data =
303 of_get_regulator_init_data(dev, child,
304 match->desc);
305 if (!match->init_data) {
306 dev_err(dev,
307 "failed to parse DT for regulator %s\n",
308 child->name);
309 of_node_put(child);
310 return -EINVAL;
311 }
312 match->of_node = of_node_get(child);
313 count++;
314 break;
315 }
316 }
317
318 return count;
319 }
320 EXPORT_SYMBOL_GPL(of_regulator_match);
321
regulator_of_get_init_data(struct device * dev,const struct regulator_desc * desc,struct regulator_config * config,struct device_node ** node)322 struct regulator_init_data *regulator_of_get_init_data(struct device *dev,
323 const struct regulator_desc *desc,
324 struct regulator_config *config,
325 struct device_node **node)
326 {
327 struct device_node *search, *child;
328 struct regulator_init_data *init_data = NULL;
329 const char *name;
330
331 if (!dev->of_node || !desc->of_match)
332 return NULL;
333
334 if (desc->regulators_node)
335 search = of_get_child_by_name(dev->of_node,
336 desc->regulators_node);
337 else
338 search = of_node_get(dev->of_node);
339
340 if (!search) {
341 dev_dbg(dev, "Failed to find regulator container node '%s'\n",
342 desc->regulators_node);
343 return NULL;
344 }
345
346 for_each_available_child_of_node(search, child) {
347 name = of_get_property(child, "regulator-compatible", NULL);
348 if (!name)
349 name = child->name;
350
351 if (strcmp(desc->of_match, name))
352 continue;
353
354 init_data = of_get_regulator_init_data(dev, child, desc);
355 if (!init_data) {
356 dev_err(dev,
357 "failed to parse DT for regulator %s\n",
358 child->name);
359 break;
360 }
361
362 if (desc->of_parse_cb) {
363 if (desc->of_parse_cb(child, desc, config)) {
364 dev_err(dev,
365 "driver callback failed to parse DT for regulator %s\n",
366 child->name);
367 init_data = NULL;
368 break;
369 }
370 }
371
372 of_node_get(child);
373 *node = child;
374 break;
375 }
376
377 of_node_put(search);
378
379 return init_data;
380 }
381