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 = true; 181 else if (of_property_read_bool(suspend_np, 182 "regulator-off-in-suspend")) 183 suspend_state->disabled = true; 184 185 if (!of_property_read_u32(suspend_np, 186 "regulator-suspend-microvolt", &pval)) 187 suspend_state->uV = pval; 188 189 if (i == PM_SUSPEND_MEM) 190 constraints->initial_state = PM_SUSPEND_MEM; 191 192 of_node_put(suspend_np); 193 suspend_state = NULL; 194 suspend_np = NULL; 195 } 196 } 197 198 /** 199 * of_get_regulator_init_data - extract regulator_init_data structure info 200 * @dev: device requesting for regulator_init_data 201 * @node: regulator device node 202 * @desc: regulator description 203 * 204 * Populates regulator_init_data structure by extracting data from device 205 * tree node, returns a pointer to the populated struture or NULL if memory 206 * alloc fails. 207 */ 208 struct regulator_init_data *of_get_regulator_init_data(struct device *dev, 209 struct device_node *node, 210 const struct regulator_desc *desc) 211 { 212 struct regulator_init_data *init_data; 213 214 if (!node) 215 return NULL; 216 217 init_data = devm_kzalloc(dev, sizeof(*init_data), GFP_KERNEL); 218 if (!init_data) 219 return NULL; /* Out of memory? */ 220 221 of_get_regulation_constraints(node, &init_data, desc); 222 return init_data; 223 } 224 EXPORT_SYMBOL_GPL(of_get_regulator_init_data); 225 226 struct devm_of_regulator_matches { 227 struct of_regulator_match *matches; 228 unsigned int num_matches; 229 }; 230 231 static void devm_of_regulator_put_matches(struct device *dev, void *res) 232 { 233 struct devm_of_regulator_matches *devm_matches = res; 234 int i; 235 236 for (i = 0; i < devm_matches->num_matches; i++) 237 of_node_put(devm_matches->matches[i].of_node); 238 } 239 240 /** 241 * of_regulator_match - extract multiple regulator init data from device tree. 242 * @dev: device requesting the data 243 * @node: parent device node of the regulators 244 * @matches: match table for the regulators 245 * @num_matches: number of entries in match table 246 * 247 * This function uses a match table specified by the regulator driver to 248 * parse regulator init data from the device tree. @node is expected to 249 * contain a set of child nodes, each providing the init data for one 250 * regulator. The data parsed from a child node will be matched to a regulator 251 * based on either the deprecated property regulator-compatible if present, 252 * or otherwise the child node's name. Note that the match table is modified 253 * in place and an additional of_node reference is taken for each matched 254 * regulator. 255 * 256 * Returns the number of matches found or a negative error code on failure. 257 */ 258 int of_regulator_match(struct device *dev, struct device_node *node, 259 struct of_regulator_match *matches, 260 unsigned int num_matches) 261 { 262 unsigned int count = 0; 263 unsigned int i; 264 const char *name; 265 struct device_node *child; 266 struct devm_of_regulator_matches *devm_matches; 267 268 if (!dev || !node) 269 return -EINVAL; 270 271 devm_matches = devres_alloc(devm_of_regulator_put_matches, 272 sizeof(struct devm_of_regulator_matches), 273 GFP_KERNEL); 274 if (!devm_matches) 275 return -ENOMEM; 276 277 devm_matches->matches = matches; 278 devm_matches->num_matches = num_matches; 279 280 devres_add(dev, devm_matches); 281 282 for (i = 0; i < num_matches; i++) { 283 struct of_regulator_match *match = &matches[i]; 284 match->init_data = NULL; 285 match->of_node = NULL; 286 } 287 288 for_each_child_of_node(node, child) { 289 name = of_get_property(child, 290 "regulator-compatible", NULL); 291 if (!name) 292 name = child->name; 293 for (i = 0; i < num_matches; i++) { 294 struct of_regulator_match *match = &matches[i]; 295 if (match->of_node) 296 continue; 297 298 if (strcmp(match->name, name)) 299 continue; 300 301 match->init_data = 302 of_get_regulator_init_data(dev, child, 303 match->desc); 304 if (!match->init_data) { 305 dev_err(dev, 306 "failed to parse DT for regulator %s\n", 307 child->name); 308 return -EINVAL; 309 } 310 match->of_node = of_node_get(child); 311 count++; 312 break; 313 } 314 } 315 316 return count; 317 } 318 EXPORT_SYMBOL_GPL(of_regulator_match); 319 320 struct regulator_init_data *regulator_of_get_init_data(struct device *dev, 321 const struct regulator_desc *desc, 322 struct regulator_config *config, 323 struct device_node **node) 324 { 325 struct device_node *search, *child; 326 struct regulator_init_data *init_data = NULL; 327 const char *name; 328 329 if (!dev->of_node || !desc->of_match) 330 return NULL; 331 332 if (desc->regulators_node) 333 search = of_get_child_by_name(dev->of_node, 334 desc->regulators_node); 335 else 336 search = of_node_get(dev->of_node); 337 338 if (!search) { 339 dev_dbg(dev, "Failed to find regulator container node '%s'\n", 340 desc->regulators_node); 341 return NULL; 342 } 343 344 for_each_available_child_of_node(search, child) { 345 name = of_get_property(child, "regulator-compatible", NULL); 346 if (!name) 347 name = child->name; 348 349 if (strcmp(desc->of_match, name)) 350 continue; 351 352 init_data = of_get_regulator_init_data(dev, child, desc); 353 if (!init_data) { 354 dev_err(dev, 355 "failed to parse DT for regulator %s\n", 356 child->name); 357 break; 358 } 359 360 if (desc->of_parse_cb) { 361 if (desc->of_parse_cb(child, desc, config)) { 362 dev_err(dev, 363 "driver callback failed to parse DT for regulator %s\n", 364 child->name); 365 init_data = NULL; 366 break; 367 } 368 } 369 370 of_node_get(child); 371 *node = child; 372 break; 373 } 374 375 of_node_put(search); 376 377 return init_data; 378 } 379