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