1 /* 2 * Copyright (C) 2014-2015 Samsung Electronics 3 * Przemyslaw Marczak <p.marczak@samsung.com> 4 * 5 * SPDX-License-Identifier: GPL-2.0+ 6 */ 7 8 #ifndef _INCLUDE_REGULATOR_H_ 9 #define _INCLUDE_REGULATOR_H_ 10 11 /** 12 * U-Boot Voltage/Current Regulator 13 * ================================ 14 * 15 * The regulator API is based on a driver model, with the device tree support. 16 * And this header describes the functions and data types for the uclass id: 17 * 'UCLASS_REGULATOR' and the regulator driver API. 18 * 19 * The regulator uclass - is based on uclass platform data which is allocated, 20 * automatically for each regulator device on bind and 'dev->uclass_platdata' 21 * points to it. The data type is: 'struct dm_regulator_uclass_platdata'. 22 * The uclass file: 'drivers/power/regulator/regulator-uclass.c' 23 * 24 * The regulator device - is based on driver's model 'struct udevice'. 25 * The API can use regulator name in two meanings: 26 * - devname - the regulator device's name: 'dev->name' 27 * - platname - the device's platdata's name. So in the code it looks like: 28 * 'uc_pdata = dev->uclass_platdata'; 'name = uc_pdata->name'. 29 * 30 * The regulator device driver - provide an implementation of uclass operations 31 * pointed by 'dev->driver->ops' as a struct of type 'struct dm_regulator_ops'. 32 * 33 * To proper bind the regulator device, the device tree node should provide 34 * regulator constraints, like in the example below: 35 * 36 * ldo1 { 37 * regulator-name = "VDD_MMC_1.8V"; (must be unique for proper bind) 38 * regulator-min-microvolt = <1000000>; (optional) 39 * regulator-max-microvolt = <1000000>; (optional) 40 * regulator-min-microamp = <1000>; (optional) 41 * regulator-max-microamp = <1000>; (optional) 42 * regulator-always-on; (optional) 43 * regulator-boot-on; (optional) 44 * }; 45 * 46 * Note: For the proper operation, at least name constraint is needed, since 47 * it can be used when calling regulator_get_by_platname(). And the mandatory 48 * rule for this name is, that it must be globally unique for the single dts. 49 * If regulator-name property is not provided, node name will be chosen. 50 * 51 * Regulator bind: 52 * For each regulator device, the device_bind() should be called with passed 53 * device tree offset. This is required for this uclass's '.post_bind' method, 54 * which does the scan on the device node, for the 'regulator-name' constraint. 55 * If the parent is not a PMIC device, and the child is not bind by function: 56 * 'pmic_bind_childs()', then it's recommended to bind the device by call to 57 * dm_scan_fdt_node() - this is usually done automatically for bus devices, 58 * as a post bind method. 59 * 60 * Regulator get: 61 * Having the device's name constraint, we can call regulator_by_platname(), 62 * to find the required regulator. Before return, the regulator is probed, 63 * and the rest of its constraints are put into the device's uclass platform 64 * data, by the uclass regulator '.pre_probe' method. 65 * 66 * For more info about PMIC bind, please refer to file: 'include/power/pmic.h' 67 * 68 * Note: 69 * Please do not use the device_bind_by_name() function, since it pass '-1' as 70 * device node offset - and the bind will fail on uclass .post_bind method, 71 * because of missing 'regulator-name' constraint. 72 * 73 * 74 * Fixed Voltage/Current Regulator 75 * =============================== 76 * 77 * When fixed voltage regulator is needed, then enable the config: 78 * - CONFIG_DM_REGULATOR_FIXED 79 * 80 * The driver file: 'drivers/power/regulator/fixed.c', provides basic support 81 * for control the GPIO, and return the device tree constraint values. 82 * 83 * To bind the fixed voltage regulator device, we usually use a 'simple-bus' 84 * node as a parent. And 'regulator-fixed' for the driver compatible. This is 85 * the same as in the kernel. The example node of fixed regulator: 86 * 87 * simple-bus { 88 * compatible = "simple-bus"; 89 * #address-cells = <1>; 90 * #size-cells = <0>; 91 * 92 * blue_led { 93 * compatible = "regulator-fixed"; 94 * regulator-name = "VDD_LED_3.3V"; 95 * regulator-min-microvolt = <3300000>; 96 * regulator-max-microvolt = <3300000>; 97 * gpio = <&gpc1 0 GPIO_ACTIVE_LOW>; 98 * }; 99 * }; 100 * 101 * The fixed regulator devices also provide regulator uclass platform data. And 102 * devices bound from such node, can use the regulator drivers API. 103 */ 104 105 /* enum regulator_type - used for regulator_*() variant calls */ 106 enum regulator_type { 107 REGULATOR_TYPE_LDO = 0, 108 REGULATOR_TYPE_BUCK, 109 REGULATOR_TYPE_DVS, 110 REGULATOR_TYPE_FIXED, 111 REGULATOR_TYPE_OTHER, 112 }; 113 114 /** 115 * struct dm_regulator_mode - this structure holds an information about 116 * each regulator operation mode. Probably in most cases - an array. 117 * This will be probably a driver-static data, since it is device-specific. 118 * 119 * @id - a driver-specific mode id 120 * @register_value - a driver-specific value for its mode id 121 * @name - the name of mode - used for regulator command 122 * Note: 123 * The field 'id', should be always a positive number, since the negative values 124 * are reserved for the errno numbers when returns the mode id. 125 */ 126 struct dm_regulator_mode { 127 int id; /* Set only as >= 0 (negative value is reserved for errno) */ 128 int register_value; 129 const char *name; 130 }; 131 132 enum regulator_flag { 133 REGULATOR_FLAG_AUTOSET_UV = 1 << 0, 134 REGULATOR_FLAG_AUTOSET_UA = 1 << 1, 135 }; 136 137 /** 138 * struct dm_regulator_uclass_platdata - pointed by dev->uclass_platdata, and 139 * allocated on each regulator bind. This structure holds an information 140 * about each regulator's constraints and supported operation modes. 141 * There is no "step" voltage value - so driver should take care of this. 142 * 143 * @type - one of 'enum regulator_type' 144 * @mode - pointer to the regulator mode (array if more than one) 145 * @mode_count - number of '.mode' entries 146 * @min_uV* - minimum voltage (micro Volts) 147 * @max_uV* - maximum voltage (micro Volts) 148 * @min_uA* - minimum amperage (micro Amps) 149 * @max_uA* - maximum amperage (micro Amps) 150 * @always_on* - bool type, true or false 151 * @boot_on* - bool type, true or false 152 * TODO(sjg@chromium.org): Consider putting the above two into @flags 153 * @flags: - flags value (see REGULATOR_FLAG_...) 154 * @name** - fdt regulator name - should be taken from the device tree 155 * 156 * Note: 157 * * - set automatically on device probe by the uclass's '.pre_probe' method. 158 * ** - set automatically on device bind by the uclass's '.post_bind' method. 159 * The constraints: type, mode, mode_count, can be set by device driver, e.g. 160 * by the driver '.probe' method. 161 */ 162 struct dm_regulator_uclass_platdata { 163 enum regulator_type type; 164 struct dm_regulator_mode *mode; 165 int mode_count; 166 int min_uV; 167 int max_uV; 168 int min_uA; 169 int max_uA; 170 bool always_on; 171 bool boot_on; 172 const char *name; 173 int flags; 174 }; 175 176 /* Regulator device operations */ 177 struct dm_regulator_ops { 178 /** 179 * The regulator output value function calls operates on a micro Volts. 180 * 181 * get/set_value - get/set output value of the given output number 182 * @dev - regulator device 183 * Sets: 184 * @uV - set the output value [micro Volts] 185 * @return output value [uV] on success or negative errno if fail. 186 */ 187 int (*get_value)(struct udevice *dev); 188 int (*set_value)(struct udevice *dev, int uV); 189 190 /** 191 * The regulator output current function calls operates on a micro Amps. 192 * 193 * get/set_current - get/set output current of the given output number 194 * @dev - regulator device 195 * Sets: 196 * @uA - set the output current [micro Amps] 197 * @return output value [uA] on success or negative errno if fail. 198 */ 199 int (*get_current)(struct udevice *dev); 200 int (*set_current)(struct udevice *dev, int uA); 201 202 /** 203 * The most basic feature of the regulator output is its enable state. 204 * 205 * get/set_enable - get/set enable state of the given output number 206 * @dev - regulator device 207 * Sets: 208 * @enable - set true - enable or false - disable 209 * @return true/false for get; or 0 / -errno for set. 210 */ 211 bool (*get_enable)(struct udevice *dev); 212 int (*set_enable)(struct udevice *dev, bool enable); 213 214 /** 215 * The 'get/set_mode()' function calls should operate on a driver- 216 * specific mode id definitions, which should be found in: 217 * field 'id' of struct dm_regulator_mode. 218 * 219 * get/set_mode - get/set operation mode of the given output number 220 * @dev - regulator device 221 * Sets 222 * @mode_id - set output mode id (struct dm_regulator_mode->id) 223 * @return id/0 for get/set on success or negative errno if fail. 224 * Note: 225 * The field 'id' of struct type 'dm_regulator_mode', should be always 226 * a positive number, since the negative is reserved for the error. 227 */ 228 int (*get_mode)(struct udevice *dev); 229 int (*set_mode)(struct udevice *dev, int mode_id); 230 }; 231 232 /** 233 * regulator_mode: returns a pointer to the array of regulator mode info 234 * 235 * @dev - pointer to the regulator device 236 * @modep - pointer to the returned mode info array 237 * @return - count of modep entries on success or negative errno if fail. 238 */ 239 int regulator_mode(struct udevice *dev, struct dm_regulator_mode **modep); 240 241 /** 242 * regulator_get_value: get microvoltage voltage value of a given regulator 243 * 244 * @dev - pointer to the regulator device 245 * @return - positive output value [uV] on success or negative errno if fail. 246 */ 247 int regulator_get_value(struct udevice *dev); 248 249 /** 250 * regulator_set_value: set the microvoltage value of a given regulator. 251 * 252 * @dev - pointer to the regulator device 253 * @uV - the output value to set [micro Volts] 254 * @return - 0 on success or -errno val if fails 255 */ 256 int regulator_set_value(struct udevice *dev, int uV); 257 258 /** 259 * regulator_get_current: get microampere value of a given regulator 260 * 261 * @dev - pointer to the regulator device 262 * @return - positive output current [uA] on success or negative errno if fail. 263 */ 264 int regulator_get_current(struct udevice *dev); 265 266 /** 267 * regulator_set_current: set the microampere value of a given regulator. 268 * 269 * @dev - pointer to the regulator device 270 * @uA - set the output current [micro Amps] 271 * @return - 0 on success or -errno val if fails 272 */ 273 int regulator_set_current(struct udevice *dev, int uA); 274 275 /** 276 * regulator_get_enable: get regulator device enable state. 277 * 278 * @dev - pointer to the regulator device 279 * @return - true/false of enable state 280 */ 281 bool regulator_get_enable(struct udevice *dev); 282 283 /** 284 * regulator_set_enable: set regulator enable state 285 * 286 * @dev - pointer to the regulator device 287 * @enable - set true or false 288 * @return - 0 on success or -errno val if fails 289 */ 290 int regulator_set_enable(struct udevice *dev, bool enable); 291 292 /** 293 * regulator_get_mode: get active operation mode id of a given regulator 294 * 295 * @dev - pointer to the regulator device 296 * @return - positive mode 'id' number on success or -errno val if fails 297 * Note: 298 * The device can provide an array of operating modes, which is type of struct 299 * dm_regulator_mode. Each mode has it's own 'id', which should be unique inside 300 * that array. By calling this function, the driver should return an active mode 301 * id of the given regulator device. 302 */ 303 int regulator_get_mode(struct udevice *dev); 304 305 /** 306 * regulator_set_mode: set the given regulator's, active mode id 307 * 308 * @dev - pointer to the regulator device 309 * @mode_id - mode id to set ('id' field of struct type dm_regulator_mode) 310 * @return - 0 on success or -errno value if fails 311 * Note: 312 * The device can provide an array of operating modes, which is type of struct 313 * dm_regulator_mode. Each mode has it's own 'id', which should be unique inside 314 * that array. By calling this function, the driver should set the active mode 315 * of a given regulator to given by "mode_id" argument. 316 */ 317 int regulator_set_mode(struct udevice *dev, int mode_id); 318 319 /** 320 * regulators_enable_boot_on() - enable regulators needed for boot 321 * 322 * This enables all regulators which are marked to be on at boot time. This 323 * only works for regulators which don't have a range for voltage/current, 324 * since in that case it is not possible to know which value to use. 325 * 326 * This effectively calls regulator_autoset() for every regulator. 327 */ 328 int regulators_enable_boot_on(bool verbose); 329 330 /** 331 * regulator_autoset: setup the voltage/current on a regulator 332 * 333 * The setup depends on constraints found in device's uclass's platform data 334 * (struct dm_regulator_uclass_platdata): 335 * 336 * - Enable - will set - if any of: 'always_on' or 'boot_on' is set to true, 337 * or if both are unset, then the function returns 338 * - Voltage value - will set - if '.min_uV' and '.max_uV' values are equal 339 * - Current limit - will set - if '.min_uA' and '.max_uA' values are equal 340 * 341 * The function returns on the first-encountered error. 342 * 343 * @platname - expected string for dm_regulator_uclass_platdata .name field 344 * @devp - returned pointer to the regulator device - if non-NULL passed 345 * @return: 0 on success or negative value of errno. 346 */ 347 int regulator_autoset(struct udevice *dev); 348 349 /** 350 * regulator_autoset_by_name: setup the regulator given by its uclass's 351 * platform data name field. The setup depends on constraints found in device's 352 * uclass's platform data (struct dm_regulator_uclass_platdata): 353 * - Enable - will set - if any of: 'always_on' or 'boot_on' is set to true, 354 * or if both are unset, then the function returns 355 * - Voltage value - will set - if '.min_uV' and '.max_uV' values are equal 356 * - Current limit - will set - if '.min_uA' and '.max_uA' values are equal 357 * 358 * The function returns on first encountered error. 359 * 360 * @platname - expected string for dm_regulator_uclass_platdata .name field 361 * @devp - returned pointer to the regulator device - if non-NULL passed 362 * @return: 0 on success or negative value of errno. 363 * 364 * The returned 'regulator' device can be used with: 365 * - regulator_get/set_* 366 */ 367 int regulator_autoset_by_name(const char *platname, struct udevice **devp); 368 369 /** 370 * regulator_list_autoset: setup the regulators given by list of their uclass's 371 * platform data name field. The setup depends on constraints found in device's 372 * uclass's platform data. The function loops with calls to: 373 * regulator_autoset_by_name() for each name from the list. 374 * 375 * @list_platname - an array of expected strings for .name field of each 376 * regulator's uclass platdata 377 * @list_devp - an array of returned pointers to the successfully setup 378 * regulator devices if non-NULL passed 379 * @verbose - (true/false) print each regulator setup info, or be quiet 380 * @return 0 on successfully setup of all list entries, otherwise first error. 381 * 382 * The returned 'regulator' devices can be used with: 383 * - regulator_get/set_* 384 * 385 * Note: The list must ends with NULL entry, like in the "platname" list below: 386 * char *my_regulators[] = { 387 * "VCC_3.3V", 388 * "VCC_1.8V", 389 * NULL, 390 * }; 391 */ 392 int regulator_list_autoset(const char *list_platname[], 393 struct udevice *list_devp[], 394 bool verbose); 395 396 /** 397 * regulator_get_by_devname: returns the pointer to the pmic regulator device. 398 * Search by name, found in regulator device's name. 399 * 400 * @devname - expected string for 'dev->name' of regulator device 401 * @devp - returned pointer to the regulator device 402 * @return 0 on success or negative value of errno. 403 * 404 * The returned 'regulator' device is probed and can be used with: 405 * - regulator_get/set_* 406 */ 407 int regulator_get_by_devname(const char *devname, struct udevice **devp); 408 409 /** 410 * regulator_get_by_platname: returns the pointer to the pmic regulator device. 411 * Search by name, found in regulator uclass platdata. 412 * 413 * @platname - expected string for uc_pdata->name of regulator uclass platdata 414 * @devp - returns pointer to the regulator device or NULL on error 415 * @return 0 on success or negative value of errno. 416 * 417 * The returned 'regulator' device is probed and can be used with: 418 * - regulator_get/set_* 419 */ 420 int regulator_get_by_platname(const char *platname, struct udevice **devp); 421 422 #endif /* _INCLUDE_REGULATOR_H_ */ 423