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