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