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 const __be32 *min_uV, *max_uV; 32 struct regulation_constraints *constraints = &(*init_data)->constraints; 33 struct regulator_state *suspend_state; 34 struct device_node *suspend_np; 35 int ret, i; 36 u32 pval; 37 38 constraints->name = of_get_property(np, "regulator-name", NULL); 39 40 min_uV = of_get_property(np, "regulator-min-microvolt", NULL); 41 if (min_uV) 42 constraints->min_uV = be32_to_cpu(*min_uV); 43 max_uV = of_get_property(np, "regulator-max-microvolt", NULL); 44 if (max_uV) 45 constraints->max_uV = be32_to_cpu(*max_uV); 46 47 /* Voltage change possible? */ 48 if (constraints->min_uV != constraints->max_uV) 49 constraints->valid_ops_mask |= REGULATOR_CHANGE_VOLTAGE; 50 /* Only one voltage? Then make sure it's set. */ 51 if (min_uV && max_uV && constraints->min_uV == constraints->max_uV) 52 constraints->apply_uV = true; 53 54 if (!of_property_read_u32(np, "regulator-microvolt-offset", &pval)) 55 constraints->uV_offset = pval; 56 if (!of_property_read_u32(np, "regulator-min-microamp", &pval)) 57 constraints->min_uA = pval; 58 if (!of_property_read_u32(np, "regulator-max-microamp", &pval)) 59 constraints->max_uA = pval; 60 61 if (!of_property_read_u32(np, "regulator-input-current-limit-microamp", 62 &pval)) 63 constraints->ilim_uA = pval; 64 65 /* Current change possible? */ 66 if (constraints->min_uA != constraints->max_uA) 67 constraints->valid_ops_mask |= REGULATOR_CHANGE_CURRENT; 68 69 constraints->boot_on = of_property_read_bool(np, "regulator-boot-on"); 70 constraints->always_on = of_property_read_bool(np, "regulator-always-on"); 71 if (!constraints->always_on) /* status change should be possible. */ 72 constraints->valid_ops_mask |= REGULATOR_CHANGE_STATUS; 73 74 constraints->pull_down = of_property_read_bool(np, "regulator-pull-down"); 75 76 if (of_property_read_bool(np, "regulator-allow-bypass")) 77 constraints->valid_ops_mask |= REGULATOR_CHANGE_BYPASS; 78 79 if (of_property_read_bool(np, "regulator-allow-set-load")) 80 constraints->valid_ops_mask |= REGULATOR_CHANGE_DRMS; 81 82 ret = of_property_read_u32(np, "regulator-ramp-delay", &pval); 83 if (!ret) { 84 if (pval) 85 constraints->ramp_delay = pval; 86 else 87 constraints->ramp_disable = true; 88 } 89 90 ret = of_property_read_u32(np, "regulator-enable-ramp-delay", &pval); 91 if (!ret) 92 constraints->enable_time = pval; 93 94 constraints->soft_start = of_property_read_bool(np, 95 "regulator-soft-start"); 96 97 if (!of_property_read_u32(np, "regulator-initial-mode", &pval)) { 98 if (desc && desc->of_map_mode) { 99 ret = desc->of_map_mode(pval); 100 if (ret == -EINVAL) 101 pr_err("%s: invalid mode %u\n", np->name, pval); 102 else 103 constraints->initial_mode = ret; 104 } else { 105 pr_warn("%s: mapping for mode %d not defined\n", 106 np->name, pval); 107 } 108 } 109 110 if (!of_property_read_u32(np, "regulator-system-load", &pval)) 111 constraints->system_load = pval; 112 113 constraints->over_current_protection = of_property_read_bool(np, 114 "regulator-over-current-protection"); 115 116 for (i = 0; i < ARRAY_SIZE(regulator_states); i++) { 117 switch (i) { 118 case PM_SUSPEND_MEM: 119 suspend_state = &constraints->state_mem; 120 break; 121 case PM_SUSPEND_MAX: 122 suspend_state = &constraints->state_disk; 123 break; 124 case PM_SUSPEND_ON: 125 case PM_SUSPEND_FREEZE: 126 case PM_SUSPEND_STANDBY: 127 default: 128 continue; 129 } 130 131 suspend_np = of_get_child_by_name(np, regulator_states[i]); 132 if (!suspend_np || !suspend_state) 133 continue; 134 135 if (!of_property_read_u32(suspend_np, "regulator-mode", 136 &pval)) { 137 if (desc && desc->of_map_mode) { 138 ret = desc->of_map_mode(pval); 139 if (ret == -EINVAL) 140 pr_err("%s: invalid mode %u\n", 141 np->name, pval); 142 else 143 suspend_state->mode = ret; 144 } else { 145 pr_warn("%s: mapping for mode %d not defined\n", 146 np->name, pval); 147 } 148 } 149 150 if (of_property_read_bool(suspend_np, 151 "regulator-on-in-suspend")) 152 suspend_state->enabled = true; 153 else if (of_property_read_bool(suspend_np, 154 "regulator-off-in-suspend")) 155 suspend_state->disabled = true; 156 157 if (!of_property_read_u32(suspend_np, 158 "regulator-suspend-microvolt", &pval)) 159 suspend_state->uV = pval; 160 161 of_node_put(suspend_np); 162 suspend_state = NULL; 163 suspend_np = NULL; 164 } 165 } 166 167 /** 168 * of_get_regulator_init_data - extract regulator_init_data structure info 169 * @dev: device requesting for regulator_init_data 170 * @node: regulator device node 171 * @desc: regulator description 172 * 173 * Populates regulator_init_data structure by extracting data from device 174 * tree node, returns a pointer to the populated struture or NULL if memory 175 * alloc fails. 176 */ 177 struct regulator_init_data *of_get_regulator_init_data(struct device *dev, 178 struct device_node *node, 179 const struct regulator_desc *desc) 180 { 181 struct regulator_init_data *init_data; 182 183 if (!node) 184 return NULL; 185 186 init_data = devm_kzalloc(dev, sizeof(*init_data), GFP_KERNEL); 187 if (!init_data) 188 return NULL; /* Out of memory? */ 189 190 of_get_regulation_constraints(node, &init_data, desc); 191 return init_data; 192 } 193 EXPORT_SYMBOL_GPL(of_get_regulator_init_data); 194 195 struct devm_of_regulator_matches { 196 struct of_regulator_match *matches; 197 unsigned int num_matches; 198 }; 199 200 static void devm_of_regulator_put_matches(struct device *dev, void *res) 201 { 202 struct devm_of_regulator_matches *devm_matches = res; 203 int i; 204 205 for (i = 0; i < devm_matches->num_matches; i++) 206 of_node_put(devm_matches->matches[i].of_node); 207 } 208 209 /** 210 * of_regulator_match - extract multiple regulator init data from device tree. 211 * @dev: device requesting the data 212 * @node: parent device node of the regulators 213 * @matches: match table for the regulators 214 * @num_matches: number of entries in match table 215 * 216 * This function uses a match table specified by the regulator driver to 217 * parse regulator init data from the device tree. @node is expected to 218 * contain a set of child nodes, each providing the init data for one 219 * regulator. The data parsed from a child node will be matched to a regulator 220 * based on either the deprecated property regulator-compatible if present, 221 * or otherwise the child node's name. Note that the match table is modified 222 * in place and an additional of_node reference is taken for each matched 223 * regulator. 224 * 225 * Returns the number of matches found or a negative error code on failure. 226 */ 227 int of_regulator_match(struct device *dev, struct device_node *node, 228 struct of_regulator_match *matches, 229 unsigned int num_matches) 230 { 231 unsigned int count = 0; 232 unsigned int i; 233 const char *name; 234 struct device_node *child; 235 struct devm_of_regulator_matches *devm_matches; 236 237 if (!dev || !node) 238 return -EINVAL; 239 240 devm_matches = devres_alloc(devm_of_regulator_put_matches, 241 sizeof(struct devm_of_regulator_matches), 242 GFP_KERNEL); 243 if (!devm_matches) 244 return -ENOMEM; 245 246 devm_matches->matches = matches; 247 devm_matches->num_matches = num_matches; 248 249 devres_add(dev, devm_matches); 250 251 for (i = 0; i < num_matches; i++) { 252 struct of_regulator_match *match = &matches[i]; 253 match->init_data = NULL; 254 match->of_node = NULL; 255 } 256 257 for_each_child_of_node(node, child) { 258 name = of_get_property(child, 259 "regulator-compatible", NULL); 260 if (!name) 261 name = child->name; 262 for (i = 0; i < num_matches; i++) { 263 struct of_regulator_match *match = &matches[i]; 264 if (match->of_node) 265 continue; 266 267 if (strcmp(match->name, name)) 268 continue; 269 270 match->init_data = 271 of_get_regulator_init_data(dev, child, 272 match->desc); 273 if (!match->init_data) { 274 dev_err(dev, 275 "failed to parse DT for regulator %s\n", 276 child->name); 277 return -EINVAL; 278 } 279 match->of_node = of_node_get(child); 280 count++; 281 break; 282 } 283 } 284 285 return count; 286 } 287 EXPORT_SYMBOL_GPL(of_regulator_match); 288 289 struct regulator_init_data *regulator_of_get_init_data(struct device *dev, 290 const struct regulator_desc *desc, 291 struct regulator_config *config, 292 struct device_node **node) 293 { 294 struct device_node *search, *child; 295 struct regulator_init_data *init_data = NULL; 296 const char *name; 297 298 if (!dev->of_node || !desc->of_match) 299 return NULL; 300 301 if (desc->regulators_node) 302 search = of_get_child_by_name(dev->of_node, 303 desc->regulators_node); 304 else 305 search = dev->of_node; 306 307 if (!search) { 308 dev_dbg(dev, "Failed to find regulator container node '%s'\n", 309 desc->regulators_node); 310 return NULL; 311 } 312 313 for_each_available_child_of_node(search, child) { 314 name = of_get_property(child, "regulator-compatible", NULL); 315 if (!name) 316 name = child->name; 317 318 if (strcmp(desc->of_match, name)) 319 continue; 320 321 init_data = of_get_regulator_init_data(dev, child, desc); 322 if (!init_data) { 323 dev_err(dev, 324 "failed to parse DT for regulator %s\n", 325 child->name); 326 break; 327 } 328 329 if (desc->of_parse_cb) { 330 if (desc->of_parse_cb(child, desc, config)) { 331 dev_err(dev, 332 "driver callback failed to parse DT for regulator %s\n", 333 child->name); 334 init_data = NULL; 335 break; 336 } 337 } 338 339 of_node_get(child); 340 *node = child; 341 break; 342 } 343 344 of_node_put(search); 345 346 return init_data; 347 } 348