drivers/regulator/mp8859.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 //
   3 // Copyright (c) 2019 five technologies GmbH
   4 // Author: Markus Reichl <m.reichl@fivetechno.de>
   5
   6 #include <linux/module.h>
   7 #include <linux/i2c.h>
   8 #include <linux/of.h>
   9 #include <linux/regulator/driver.h>
  10 #include <linux/regmap.h>
  11
  12
  13 #define VOL_MIN_IDX                     0x00
  14 #define VOL_MAX_IDX                     0x7ff
  15
  16 /* Register definitions */
  17 #define MP8859_VOUT_L_REG               0    //3 lo Bits
  18 #define MP8859_VOUT_H_REG               1    //8 hi Bits
  19 #define MP8859_VOUT_GO_REG              2
  20 #define MP8859_IOUT_LIM_REG             3
  21 #define MP8859_CTL1_REG                 4
  22 #define MP8859_CTL2_REG                 5
  23 #define MP8859_RESERVED1_REG            6
  24 #define MP8859_RESERVED2_REG            7
  25 #define MP8859_RESERVED3_REG            8
  26 #define MP8859_STATUS_REG               9
  27 #define MP8859_INTERRUPT_REG            0x0A
  28 #define MP8859_MASK_REG                 0x0B
  29 #define MP8859_ID1_REG                  0x0C
  30 #define MP8859_MFR_ID_REG               0x27
  31 #define MP8859_DEV_ID_REG               0x28
  32 #define MP8859_IC_REV_REG               0x29
  33
  34 #define MP8859_MAX_REG                  0x29
  35
  36 #define MP8859_GO_BIT                   0x01
  37
  38 #define MP8859_IOUT_LIM_MASK            0x7f
  39
  40 #define MP8859_ENABLE_MASK              0x80
  41 #define MP8859_DISCHG_EN_MASK           0x10
  42 #define MP8859_MODE_MASK                0x08
  43
  44 #define MP8859_PG_MASK                  0x80
  45 #define MP8859_OTP_MASK                 0x40
  46 #define MP8859_OTW_MASK                 0x20
  47 #define MP8859_CC_CV_MASK               0x10
  48
  49 static int mp8859_set_voltage_sel(struct regulator_dev *rdev, unsigned int sel)
  50 {
  51         int ret;
  52
  53         ret = regmap_write(rdev->regmap, MP8859_VOUT_L_REG, sel & 0x7);
  54
  55         if (ret)
  56                 return ret;
  57         ret = regmap_write(rdev->regmap, MP8859_VOUT_H_REG, sel >> 3);
  58
  59         if (ret)
  60                 return ret;
  61         ret = regmap_update_bits(rdev->regmap, MP8859_VOUT_GO_REG,
  62                                         MP8859_GO_BIT, 1);
  63         return ret;
  64 }
  65
  66 static int mp8859_get_voltage_sel(struct regulator_dev *rdev)
  67 {
  68         unsigned int val_tmp;
  69         unsigned int val;
  70         int ret;
  71
  72         ret = regmap_read(rdev->regmap, MP8859_VOUT_H_REG, &val_tmp);
  73
  74         if (ret)
  75                 return ret;
  76         val = val_tmp << 3;
  77
  78         ret = regmap_read(rdev->regmap, MP8859_VOUT_L_REG, &val_tmp);
  79
  80         if (ret)
  81                 return ret;
  82         val |= val_tmp & 0x07;
  83         return val;
  84 }
  85
  86 static int mp8859_set_voltage_time_sel(struct regulator_dev *rdev,
  87                                        unsigned int from, unsigned int to)
  88 {
  89         int change;
  90
  91         /* The voltage ramps at 1mV/uS, selectors are 10mV */
  92         if (from > to)
  93                 change = from - to;
  94         else
  95                 change = to - from;
  96
  97         return change * 10 * 1000;
  98 }
  99
 100 static unsigned int mp8859_get_mode(struct regulator_dev *rdev)
 101 {
 102         unsigned int val;
 103         int ret;
 104
 105         ret = regmap_read(rdev->regmap, MP8859_CTL1_REG, &val);
 106         if (ret != 0) {
 107                 dev_err(&rdev->dev, "Failed to read mode: %d\n", ret);
 108                 return 0;
 109         }
 110
 111         if (val & MP8859_MODE_MASK)
 112                 return REGULATOR_MODE_FAST;
 113         else
 114                 return REGULATOR_MODE_NORMAL;
 115 }
 116
 117 static int mp8859_set_mode(struct regulator_dev *rdev, unsigned int mode)
 118 {
 119         unsigned int val;
 120
 121         switch (mode) {
 122         case REGULATOR_MODE_FAST:
 123                 val = MP8859_MODE_MASK;
 124                 break;
 125         case REGULATOR_MODE_NORMAL:
 126                 val = 0;
 127                 break;
 128         default:
 129                 return -EINVAL;
 130         }
 131
 132         return regmap_update_bits(rdev->regmap, MP8859_CTL1_REG,
 133                                   MP8859_MODE_MASK, val);
 134 }
 135
 136 static int mp8859_set_current_limit(struct regulator_dev *rdev,
 137                                     int min_uA, int max_uA)
 138 {
 139         unsigned int cur_val, new_val;
 140         int ret, i;
 141
 142         /* Steps of 50mA */
 143         new_val = max_uA / 50000;
 144         if (new_val > MP8859_IOUT_LIM_MASK)
 145                 return -EINVAL;
 146         if (new_val == 0)
 147                 return -EINVAL;
 148
 149         /*
 150          * If the regulator is limiting then ramp gradually as per
 151          * datasheet, otherwise just set the value directly.
 152          */
 153         ret = regmap_read(rdev->regmap, MP8859_STATUS_REG, &cur_val);
 154         if (ret != 0)
 155                 return ret;
 156         if (!(cur_val & MP8859_CC_CV_MASK)) {
 157                 return regmap_update_bits(rdev->regmap, MP8859_IOUT_LIM_REG,
 158                                           MP8859_IOUT_LIM_MASK, new_val);
 159         }
 160
 161         ret = regmap_read(rdev->regmap, MP8859_IOUT_LIM_REG, &cur_val);
 162         if (ret != 0)
 163                 return ret;
 164
 165         if (cur_val >= new_val) {
 166                 for (i = cur_val; i >= new_val; i--) {
 167                         ret = regmap_update_bits(rdev->regmap,
 168                                                  MP8859_IOUT_LIM_REG,
 169                                                  MP8859_IOUT_LIM_MASK,
 170                                                  cur_val - i);
 171                         if (ret != 0)
 172                                 return ret;
 173                 }
 174         } else {
 175                 for (i = cur_val; i <= new_val; i++) {
 176                         ret = regmap_update_bits(rdev->regmap,
 177                                                  MP8859_IOUT_LIM_REG,
 178                                                  MP8859_IOUT_LIM_MASK,
 179                                                  cur_val + i);
 180                         if (ret != 0)
 181                                 return ret;
 182                 }
 183         }
 184
 185         return 0;
 186 }
 187
 188 static int mp8859_get_status(struct regulator_dev *rdev)
 189 {
 190         unsigned int val;
 191         int ret;
 192
 193         /* Output status is only meaingful when enabled */
 194         ret = regmap_read(rdev->regmap, MP8859_CTL1_REG, &val);
 195         if (ret != 0)
 196                 return ret;
 197         if (!(val & MP8859_ENABLE_MASK))
 198                 return REGULATOR_STATUS_UNDEFINED;
 199
 200         ret = regmap_read(rdev->regmap, MP8859_STATUS_REG, &val);
 201         if (ret != 0)
 202                 return ret;
 203
 204         if (val & MP8859_PG_MASK)
 205                 return REGULATOR_STATUS_ON;
 206         else
 207                 return REGULATOR_STATUS_ERROR;
 208 }
 209
 210 static int mp8859_get_error_flags(struct regulator_dev *rdev,
 211                                   unsigned int *flags)
 212 {
 213         unsigned int status, enabled;
 214         int ret;
 215
 216         *flags = 0;
 217
 218         /* Output status is only meaingful when enabled */
 219         ret = regmap_read(rdev->regmap, MP8859_CTL1_REG, &enabled);
 220         if (ret != 0)
 221                 return ret;
 222         enabled &= MP8859_ENABLE_MASK;
 223
 224         ret = regmap_read(rdev->regmap, MP8859_STATUS_REG, &status);
 225         if (ret != 0)
 226                 return ret;
 227
 228         if (enabled && !(status & MP8859_PG_MASK))
 229                 status |= REGULATOR_ERROR_FAIL;
 230         if (status & MP8859_OTP_MASK)
 231                 status |= REGULATOR_ERROR_OVER_TEMP;
 232         if (status & MP8859_OTW_MASK)
 233                 status |= REGULATOR_ERROR_OVER_TEMP_WARN;
 234         if (status & MP8859_CC_CV_MASK)
 235                 status |= REGULATOR_ERROR_OVER_CURRENT;
 236
 237         return 0;
 238 }
 239
 240 static const struct linear_range mp8859_dcdc_ranges[] = {
 241         REGULATOR_LINEAR_RANGE(0, VOL_MIN_IDX, VOL_MAX_IDX, 10000),
 242 };
 243
 244 static bool mp8859_readable(struct device *dev, unsigned int reg)
 245 {
 246         switch (reg) {
 247         case MP8859_VOUT_L_REG:
 248         case MP8859_VOUT_H_REG:
 249         case MP8859_VOUT_GO_REG:
 250         case MP8859_IOUT_LIM_REG:
 251         case MP8859_CTL1_REG:
 252         case MP8859_CTL2_REG:
 253         case MP8859_STATUS_REG:
 254         case MP8859_INTERRUPT_REG:
 255         case MP8859_MASK_REG:
 256         case MP8859_ID1_REG:
 257         case MP8859_MFR_ID_REG:
 258         case MP8859_DEV_ID_REG:
 259         case MP8859_IC_REV_REG:
 260                 return true;
 261         default:
 262                 return false;
 263         }
 264 }
 265
 266 static bool mp8859_volatile(struct device *dev, unsigned int reg)
 267 {
 268         switch (reg) {
 269         case MP8859_VOUT_GO_REG:
 270         case MP8859_STATUS_REG:
 271         case MP8859_INTERRUPT_REG:
 272                 return true;
 273         default:
 274                 return false;
 275         }
 276 }
 277
 278 static const struct regmap_config mp8859_regmap = {
 279         .reg_bits = 8,
 280         .val_bits = 8,
 281         .max_register = MP8859_MAX_REG,
 282         .cache_type = REGCACHE_MAPLE,
 283         .readable_reg = mp8859_readable,
 284         .volatile_reg = mp8859_volatile,
 285 };
 286
 287 static const struct regulator_ops mp8859_ops = {
 288         .set_voltage_sel = mp8859_set_voltage_sel,
 289         .get_voltage_sel = mp8859_get_voltage_sel,
 290         .list_voltage = regulator_list_voltage_linear_range,
 291         .set_voltage_time_sel = mp8859_set_voltage_time_sel,
 292         .enable = regulator_enable_regmap,
 293         .disable = regulator_disable_regmap,
 294         .is_enabled = regulator_is_enabled_regmap,
 295         .set_mode = mp8859_set_mode,
 296         .get_mode = mp8859_get_mode,
 297         .set_active_discharge = regulator_set_active_discharge_regmap,
 298         .set_current_limit = mp8859_set_current_limit,
 299         .get_status = mp8859_get_status,
 300         .get_error_flags = mp8859_get_error_flags,
 301 };
 302
 303 static const struct regulator_desc mp8859_regulators[] = {
 304         {
 305                 .id = 0,
 306                 .type = REGULATOR_VOLTAGE,
 307                 .name = "mp8859_dcdc",
 308                 .supply_name = "vin",
 309                 .of_match = of_match_ptr("mp8859_dcdc"),
 310                 .n_voltages = VOL_MAX_IDX + 1,
 311                 .linear_ranges = mp8859_dcdc_ranges,
 312                 .n_linear_ranges = 1,
 313                 .enable_reg = MP8859_CTL1_REG,
 314                 .enable_mask = MP8859_ENABLE_MASK,
 315                 .enable_val = MP8859_ENABLE_MASK,
 316                 .active_discharge_reg = MP8859_CTL1_REG,
 317                 .active_discharge_on = MP8859_DISCHG_EN_MASK,
 318                 .active_discharge_mask = MP8859_DISCHG_EN_MASK,
 319                 .ops = &mp8859_ops,
 320                 .owner = THIS_MODULE,
 321         },
 322 };
 323
 324 static int mp8859_i2c_probe(struct i2c_client *i2c)
 325 {
 326         int ret;
 327         struct regulator_config config = {.dev = &i2c->dev};
 328         struct regmap *regmap = devm_regmap_init_i2c(i2c, &mp8859_regmap);
 329         struct regulator_dev *rdev;
 330         unsigned int val, rev;
 331
 332         if (IS_ERR(regmap)) {
 333                 ret = PTR_ERR(regmap);
 334                 dev_err(&i2c->dev, "regmap init failed: %d\n", ret);
 335                 return ret;
 336         }
 337
 338         ret = regmap_read(regmap, MP8859_MFR_ID_REG, &val);
 339         if (ret != 0) {
 340                 dev_err(&i2c->dev, "Failed to read manufacturer ID: %d\n", ret);
 341                 return ret;
 342         }
 343         if (val != 0x9) {
 344                 dev_err(&i2c->dev, "Manufacturer ID %x != 9\n", val);
 345                 return -EINVAL;
 346         }
 347
 348         ret = regmap_read(regmap, MP8859_DEV_ID_REG, &val);
 349         if (ret != 0) {
 350                 dev_err(&i2c->dev, "Failed to read device ID: %d\n", ret);
 351                 return ret;
 352         }
 353         if (val != 0x58) {
 354                 dev_err(&i2c->dev, "Manufacturer ID %x != 0x58\n", val);
 355                 return -EINVAL;
 356         }
 357
 358         ret = regmap_read(regmap, MP8859_IC_REV_REG, &rev);
 359         if (ret != 0) {
 360                 dev_err(&i2c->dev, "Failed to read device revision: %d\n", ret);
 361                 return ret;
 362         }
 363         ret = regmap_read(regmap, MP8859_ID1_REG, &val);
 364         if (ret != 0) {
 365                 dev_err(&i2c->dev, "Failed to read device ID1: %d\n", ret);
 366                 return ret;
 367         }
 368         dev_info(&i2c->dev, "MP8859-%04d revision %d\n", val, rev);
 369
 370         rdev = devm_regulator_register(&i2c->dev, &mp8859_regulators[0],
 371                                         &config);
 372
 373         if (IS_ERR(rdev)) {
 374                 ret = PTR_ERR(rdev);
 375                 dev_err(&i2c->dev, "failed to register %s: %d\n",
 376                         mp8859_regulators[0].name, ret);
 377                 return ret;
 378         }
 379         return 0;
 380 }
 381
 382 static const struct of_device_id mp8859_dt_id[] __maybe_unused = {
 383         {.compatible =  "mps,mp8859"},
 384         {},
 385 };
 386 MODULE_DEVICE_TABLE(of, mp8859_dt_id);
 387
 388 static const struct i2c_device_id mp8859_i2c_id[] = {
 389         { "mp8859", },
 390         {  },
 391 };
 392 MODULE_DEVICE_TABLE(i2c, mp8859_i2c_id);
 393
 394 static struct i2c_driver mp8859_regulator_driver = {
 395         .driver = {
 396                 .name = "mp8859",
 397                 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
 398                 .of_match_table = of_match_ptr(mp8859_dt_id),
 399         },
 400         .probe = mp8859_i2c_probe,
 401         .id_table = mp8859_i2c_id,
 402 };
 403
 404 module_i2c_driver(mp8859_regulator_driver);
 405
 406 MODULE_DESCRIPTION("Monolithic Power Systems MP8859 voltage regulator driver");
 407 MODULE_AUTHOR("Markus Reichl <m.reichl@fivetechno.de>");
 408 MODULE_LICENSE("GPL v2");