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