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