drivers/regulator/of_regulator.c

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