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-settling-time-up-us", &pval); 94 if (!ret) 95 constraints->settling_time_up = pval; 96 if (constraints->settling_time_up && constraints->settling_time) { 97 pr_warn("%s: ambiguous configuration for settling time, ignoring 'regulator-settling-time-up-us'\n", 98 np->name); 99 constraints->settling_time_up = 0; 100 } 101 102 ret = of_property_read_u32(np, "regulator-settling-time-down-us", 103 &pval); 104 if (!ret) 105 constraints->settling_time_down = pval; 106 if (constraints->settling_time_down && constraints->settling_time) { 107 pr_warn("%s: ambiguous configuration for settling time, ignoring 'regulator-settling-time-down-us'\n", 108 np->name); 109 constraints->settling_time_down = 0; 110 } 111 112 ret = of_property_read_u32(np, "regulator-enable-ramp-delay", &pval); 113 if (!ret) 114 constraints->enable_time = pval; 115 116 constraints->soft_start = of_property_read_bool(np, 117 "regulator-soft-start"); 118 ret = of_property_read_u32(np, "regulator-active-discharge", &pval); 119 if (!ret) { 120 constraints->active_discharge = 121 (pval) ? REGULATOR_ACTIVE_DISCHARGE_ENABLE : 122 REGULATOR_ACTIVE_DISCHARGE_DISABLE; 123 } 124 125 if (!of_property_read_u32(np, "regulator-initial-mode", &pval)) { 126 if (desc && desc->of_map_mode) { 127 ret = desc->of_map_mode(pval); 128 if (ret == -EINVAL) 129 pr_err("%s: invalid mode %u\n", np->name, pval); 130 else 131 constraints->initial_mode = ret; 132 } else { 133 pr_warn("%s: mapping for mode %d not defined\n", 134 np->name, pval); 135 } 136 } 137 138 if (!of_property_read_u32(np, "regulator-system-load", &pval)) 139 constraints->system_load = pval; 140 141 constraints->over_current_protection = of_property_read_bool(np, 142 "regulator-over-current-protection"); 143 144 for (i = 0; i < ARRAY_SIZE(regulator_states); i++) { 145 switch (i) { 146 case PM_SUSPEND_MEM: 147 suspend_state = &constraints->state_mem; 148 break; 149 case PM_SUSPEND_MAX: 150 suspend_state = &constraints->state_disk; 151 break; 152 case PM_SUSPEND_ON: 153 case PM_SUSPEND_TO_IDLE: 154 case PM_SUSPEND_STANDBY: 155 default: 156 continue; 157 } 158 159 suspend_np = of_get_child_by_name(np, regulator_states[i]); 160 if (!suspend_np || !suspend_state) 161 continue; 162 163 if (!of_property_read_u32(suspend_np, "regulator-mode", 164 &pval)) { 165 if (desc && desc->of_map_mode) { 166 ret = desc->of_map_mode(pval); 167 if (ret == -EINVAL) 168 pr_err("%s: invalid mode %u\n", 169 np->name, pval); 170 else 171 suspend_state->mode = ret; 172 } else { 173 pr_warn("%s: mapping for mode %d not defined\n", 174 np->name, pval); 175 } 176 } 177 178 if (of_property_read_bool(suspend_np, 179 "regulator-on-in-suspend")) 180 suspend_state->enabled = ENABLE_IN_SUSPEND; 181 else if (of_property_read_bool(suspend_np, 182 "regulator-off-in-suspend")) 183 suspend_state->enabled = DISABLE_IN_SUSPEND; 184 else 185 suspend_state->enabled = DO_NOTHING_IN_SUSPEND; 186 187 if (!of_property_read_u32(np, "regulator-suspend-min-microvolt", 188 &pval)) 189 suspend_state->min_uV = pval; 190 191 if (!of_property_read_u32(np, "regulator-suspend-max-microvolt", 192 &pval)) 193 suspend_state->max_uV = pval; 194 195 if (!of_property_read_u32(suspend_np, 196 "regulator-suspend-microvolt", &pval)) 197 suspend_state->uV = pval; 198 else /* otherwise use min_uV as default suspend voltage */ 199 suspend_state->uV = suspend_state->min_uV; 200 201 if (of_property_read_bool(suspend_np, 202 "regulator-changeable-in-suspend")) 203 suspend_state->changeable = true; 204 205 if (i == PM_SUSPEND_MEM) 206 constraints->initial_state = PM_SUSPEND_MEM; 207 208 of_node_put(suspend_np); 209 suspend_state = NULL; 210 suspend_np = NULL; 211 } 212 } 213 214 /** 215 * of_get_regulator_init_data - extract regulator_init_data structure info 216 * @dev: device requesting for regulator_init_data 217 * @node: regulator device node 218 * @desc: regulator description 219 * 220 * Populates regulator_init_data structure by extracting data from device 221 * tree node, returns a pointer to the populated struture or NULL if memory 222 * alloc fails. 223 */ 224 struct regulator_init_data *of_get_regulator_init_data(struct device *dev, 225 struct device_node *node, 226 const struct regulator_desc *desc) 227 { 228 struct regulator_init_data *init_data; 229 230 if (!node) 231 return NULL; 232 233 init_data = devm_kzalloc(dev, sizeof(*init_data), GFP_KERNEL); 234 if (!init_data) 235 return NULL; /* Out of memory? */ 236 237 of_get_regulation_constraints(node, &init_data, desc); 238 return init_data; 239 } 240 EXPORT_SYMBOL_GPL(of_get_regulator_init_data); 241 242 struct devm_of_regulator_matches { 243 struct of_regulator_match *matches; 244 unsigned int num_matches; 245 }; 246 247 static void devm_of_regulator_put_matches(struct device *dev, void *res) 248 { 249 struct devm_of_regulator_matches *devm_matches = res; 250 int i; 251 252 for (i = 0; i < devm_matches->num_matches; i++) 253 of_node_put(devm_matches->matches[i].of_node); 254 } 255 256 /** 257 * of_regulator_match - extract multiple regulator init data from device tree. 258 * @dev: device requesting the data 259 * @node: parent device node of the regulators 260 * @matches: match table for the regulators 261 * @num_matches: number of entries in match table 262 * 263 * This function uses a match table specified by the regulator driver to 264 * parse regulator init data from the device tree. @node is expected to 265 * contain a set of child nodes, each providing the init data for one 266 * regulator. The data parsed from a child node will be matched to a regulator 267 * based on either the deprecated property regulator-compatible if present, 268 * or otherwise the child node's name. Note that the match table is modified 269 * in place and an additional of_node reference is taken for each matched 270 * regulator. 271 * 272 * Returns the number of matches found or a negative error code on failure. 273 */ 274 int of_regulator_match(struct device *dev, struct device_node *node, 275 struct of_regulator_match *matches, 276 unsigned int num_matches) 277 { 278 unsigned int count = 0; 279 unsigned int i; 280 const char *name; 281 struct device_node *child; 282 struct devm_of_regulator_matches *devm_matches; 283 284 if (!dev || !node) 285 return -EINVAL; 286 287 devm_matches = devres_alloc(devm_of_regulator_put_matches, 288 sizeof(struct devm_of_regulator_matches), 289 GFP_KERNEL); 290 if (!devm_matches) 291 return -ENOMEM; 292 293 devm_matches->matches = matches; 294 devm_matches->num_matches = num_matches; 295 296 devres_add(dev, devm_matches); 297 298 for (i = 0; i < num_matches; i++) { 299 struct of_regulator_match *match = &matches[i]; 300 match->init_data = NULL; 301 match->of_node = NULL; 302 } 303 304 for_each_child_of_node(node, child) { 305 name = of_get_property(child, 306 "regulator-compatible", NULL); 307 if (!name) 308 name = child->name; 309 for (i = 0; i < num_matches; i++) { 310 struct of_regulator_match *match = &matches[i]; 311 if (match->of_node) 312 continue; 313 314 if (strcmp(match->name, name)) 315 continue; 316 317 match->init_data = 318 of_get_regulator_init_data(dev, child, 319 match->desc); 320 if (!match->init_data) { 321 dev_err(dev, 322 "failed to parse DT for regulator %s\n", 323 child->name); 324 return -EINVAL; 325 } 326 match->of_node = of_node_get(child); 327 count++; 328 break; 329 } 330 } 331 332 return count; 333 } 334 EXPORT_SYMBOL_GPL(of_regulator_match); 335 336 struct regulator_init_data *regulator_of_get_init_data(struct device *dev, 337 const struct regulator_desc *desc, 338 struct regulator_config *config, 339 struct device_node **node) 340 { 341 struct device_node *search, *child; 342 struct regulator_init_data *init_data = NULL; 343 const char *name; 344 345 if (!dev->of_node || !desc->of_match) 346 return NULL; 347 348 if (desc->regulators_node) 349 search = of_get_child_by_name(dev->of_node, 350 desc->regulators_node); 351 else 352 search = of_node_get(dev->of_node); 353 354 if (!search) { 355 dev_dbg(dev, "Failed to find regulator container node '%s'\n", 356 desc->regulators_node); 357 return NULL; 358 } 359 360 for_each_available_child_of_node(search, child) { 361 name = of_get_property(child, "regulator-compatible", NULL); 362 if (!name) 363 name = child->name; 364 365 if (strcmp(desc->of_match, name)) 366 continue; 367 368 init_data = of_get_regulator_init_data(dev, child, desc); 369 if (!init_data) { 370 dev_err(dev, 371 "failed to parse DT for regulator %s\n", 372 child->name); 373 break; 374 } 375 376 if (desc->of_parse_cb) { 377 if (desc->of_parse_cb(child, desc, config)) { 378 dev_err(dev, 379 "driver callback failed to parse DT for regulator %s\n", 380 child->name); 381 init_data = NULL; 382 break; 383 } 384 } 385 386 of_node_get(child); 387 *node = child; 388 break; 389 } 390 391 of_node_put(search); 392 393 return init_data; 394 } 395 396 static int of_node_match(struct device *dev, const void *data) 397 { 398 return dev->of_node == data; 399 } 400 401 struct regulator_dev *of_find_regulator_by_node(struct device_node *np) 402 { 403 struct device *dev; 404 405 dev = class_find_device(®ulator_class, NULL, np, of_node_match); 406 407 return dev ? dev_to_rdev(dev) : NULL; 408 } 409