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 } 360