drivers/leds/leds-lp8860.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * TI LP8860 4-Channel LED Driver
   4  *
   5  * Copyright (C) 2014 Texas Instruments
   6  *
   7  * Author: Dan Murphy <dmurphy@ti.com>
   8  */
   9
  10 #include <linux/i2c.h>
  11 #include <linux/init.h>
  12 #include <linux/leds.h>
  13 #include <linux/regmap.h>
  14 #include <linux/regulator/consumer.h>
  15 #include <linux/module.h>
  16 #include <linux/mutex.h>
  17 #include <linux/of.h>
  18 #include <linux/gpio/consumer.h>
  19 #include <linux/slab.h>
  20
  21 #define LP8860_DISP_CL1_BRT_MSB         0x00
  22 #define LP8860_DISP_CL1_BRT_LSB         0x01
  23 #define LP8860_DISP_CL1_CURR_MSB        0x02
  24 #define LP8860_DISP_CL1_CURR_LSB        0x03
  25 #define LP8860_CL2_BRT_MSB              0x04
  26 #define LP8860_CL2_BRT_LSB              0x05
  27 #define LP8860_CL2_CURRENT              0x06
  28 #define LP8860_CL3_BRT_MSB              0x07
  29 #define LP8860_CL3_BRT_LSB              0x08
  30 #define LP8860_CL3_CURRENT              0x09
  31 #define LP8860_CL4_BRT_MSB              0x0a
  32 #define LP8860_CL4_BRT_LSB              0x0b
  33 #define LP8860_CL4_CURRENT              0x0c
  34 #define LP8860_CONFIG                   0x0d
  35 #define LP8860_STATUS                   0x0e
  36 #define LP8860_FAULT                    0x0f
  37 #define LP8860_LED_FAULT                0x10
  38 #define LP8860_FAULT_CLEAR              0x11
  39 #define LP8860_ID                       0x12
  40 #define LP8860_TEMP_MSB                 0x13
  41 #define LP8860_TEMP_LSB                 0x14
  42 #define LP8860_DISP_LED_CURR_MSB        0x15
  43 #define LP8860_DISP_LED_CURR_LSB        0x16
  44 #define LP8860_DISP_LED_PWM_MSB         0x17
  45 #define LP8860_DISP_LED_PWM_LSB         0x18
  46 #define LP8860_EEPROM_CNTRL             0x19
  47 #define LP8860_EEPROM_UNLOCK            0x1a
  48
  49 #define LP8860_EEPROM_REG_0             0x60
  50 #define LP8860_EEPROM_REG_1             0x61
  51 #define LP8860_EEPROM_REG_2             0x62
  52 #define LP8860_EEPROM_REG_3             0x63
  53 #define LP8860_EEPROM_REG_4             0x64
  54 #define LP8860_EEPROM_REG_5             0x65
  55 #define LP8860_EEPROM_REG_6             0x66
  56 #define LP8860_EEPROM_REG_7             0x67
  57 #define LP8860_EEPROM_REG_8             0x68
  58 #define LP8860_EEPROM_REG_9             0x69
  59 #define LP8860_EEPROM_REG_10            0x6a
  60 #define LP8860_EEPROM_REG_11            0x6b
  61 #define LP8860_EEPROM_REG_12            0x6c
  62 #define LP8860_EEPROM_REG_13            0x6d
  63 #define LP8860_EEPROM_REG_14            0x6e
  64 #define LP8860_EEPROM_REG_15            0x6f
  65 #define LP8860_EEPROM_REG_16            0x70
  66 #define LP8860_EEPROM_REG_17            0x71
  67 #define LP8860_EEPROM_REG_18            0x72
  68 #define LP8860_EEPROM_REG_19            0x73
  69 #define LP8860_EEPROM_REG_20            0x74
  70 #define LP8860_EEPROM_REG_21            0x75
  71 #define LP8860_EEPROM_REG_22            0x76
  72 #define LP8860_EEPROM_REG_23            0x77
  73 #define LP8860_EEPROM_REG_24            0x78
  74
  75 #define LP8860_LOCK_EEPROM              0x00
  76 #define LP8860_UNLOCK_EEPROM            0x01
  77 #define LP8860_PROGRAM_EEPROM           0x02
  78 #define LP8860_EEPROM_CODE_1            0x08
  79 #define LP8860_EEPROM_CODE_2            0xba
  80 #define LP8860_EEPROM_CODE_3            0xef
  81
  82 #define LP8860_CLEAR_FAULTS             0x01
  83
  84 #define LP8860_NAME                     "lp8860"
  85
  86 /**
  87  * struct lp8860_led
  88  * @lock: Lock for reading/writing the device
  89  * @client: Pointer to the I2C client
  90  * @led_dev: led class device pointer
  91  * @regmap: Devices register map
  92  * @eeprom_regmap: EEPROM register map
  93  * @enable_gpio: VDDIO/EN gpio to enable communication interface
  94  * @regulator: LED supply regulator pointer
  95  */
  96 struct lp8860_led {
  97         struct mutex lock;
  98         struct i2c_client *client;
  99         struct led_classdev led_dev;
 100         struct regmap *regmap;
 101         struct regmap *eeprom_regmap;
 102         struct gpio_desc *enable_gpio;
 103         struct regulator *regulator;
 104 };
 105
 106 struct lp8860_eeprom_reg {
 107         uint8_t reg;
 108         uint8_t value;
 109 };
 110
 111 static struct lp8860_eeprom_reg lp8860_eeprom_disp_regs[] = {
 112         { LP8860_EEPROM_REG_0, 0xed },
 113         { LP8860_EEPROM_REG_1, 0xdf },
 114         { LP8860_EEPROM_REG_2, 0xdc },
 115         { LP8860_EEPROM_REG_3, 0xf0 },
 116         { LP8860_EEPROM_REG_4, 0xdf },
 117         { LP8860_EEPROM_REG_5, 0xe5 },
 118         { LP8860_EEPROM_REG_6, 0xf2 },
 119         { LP8860_EEPROM_REG_7, 0x77 },
 120         { LP8860_EEPROM_REG_8, 0x77 },
 121         { LP8860_EEPROM_REG_9, 0x71 },
 122         { LP8860_EEPROM_REG_10, 0x3f },
 123         { LP8860_EEPROM_REG_11, 0xb7 },
 124         { LP8860_EEPROM_REG_12, 0x17 },
 125         { LP8860_EEPROM_REG_13, 0xef },
 126         { LP8860_EEPROM_REG_14, 0xb0 },
 127         { LP8860_EEPROM_REG_15, 0x87 },
 128         { LP8860_EEPROM_REG_16, 0xce },
 129         { LP8860_EEPROM_REG_17, 0x72 },
 130         { LP8860_EEPROM_REG_18, 0xe5 },
 131         { LP8860_EEPROM_REG_19, 0xdf },
 132         { LP8860_EEPROM_REG_20, 0x35 },
 133         { LP8860_EEPROM_REG_21, 0x06 },
 134         { LP8860_EEPROM_REG_22, 0xdc },
 135         { LP8860_EEPROM_REG_23, 0x88 },
 136         { LP8860_EEPROM_REG_24, 0x3E },
 137 };
 138
 139 static int lp8860_unlock_eeprom(struct lp8860_led *led, int lock)
 140 {
 141         int ret;
 142
 143         mutex_lock(&led->lock);
 144
 145         if (lock == LP8860_UNLOCK_EEPROM) {
 146                 ret = regmap_write(led->regmap,
 147                         LP8860_EEPROM_UNLOCK,
 148                         LP8860_EEPROM_CODE_1);
 149                 if (ret) {
 150                         dev_err(&led->client->dev, "EEPROM Unlock failed\n");
 151                         goto out;
 152                 }
 153
 154                 ret = regmap_write(led->regmap,
 155                         LP8860_EEPROM_UNLOCK,
 156                         LP8860_EEPROM_CODE_2);
 157                 if (ret) {
 158                         dev_err(&led->client->dev, "EEPROM Unlock failed\n");
 159                         goto out;
 160                 }
 161                 ret = regmap_write(led->regmap,
 162                         LP8860_EEPROM_UNLOCK,
 163                         LP8860_EEPROM_CODE_3);
 164                 if (ret) {
 165                         dev_err(&led->client->dev, "EEPROM Unlock failed\n");
 166                         goto out;
 167                 }
 168         } else {
 169                 ret = regmap_write(led->regmap,
 170                         LP8860_EEPROM_UNLOCK,
 171                         LP8860_LOCK_EEPROM);
 172         }
 173
 174 out:
 175         mutex_unlock(&led->lock);
 176         return ret;
 177 }
 178
 179 static int lp8860_fault_check(struct lp8860_led *led)
 180 {
 181         int ret, fault;
 182         unsigned int read_buf;
 183
 184         ret = regmap_read(led->regmap, LP8860_LED_FAULT, &read_buf);
 185         if (ret)
 186                 goto out;
 187
 188         fault = read_buf;
 189
 190         ret = regmap_read(led->regmap, LP8860_FAULT, &read_buf);
 191         if (ret)
 192                 goto out;
 193
 194         fault |= read_buf;
 195
 196         /* Attempt to clear any faults */
 197         if (fault)
 198                 ret = regmap_write(led->regmap, LP8860_FAULT_CLEAR,
 199                         LP8860_CLEAR_FAULTS);
 200 out:
 201         return ret;
 202 }
 203
 204 static int lp8860_brightness_set(struct led_classdev *led_cdev,
 205                                 enum led_brightness brt_val)
 206 {
 207         struct lp8860_led *led =
 208                         container_of(led_cdev, struct lp8860_led, led_dev);
 209         int disp_brightness = brt_val * 255;
 210         int ret;
 211
 212         mutex_lock(&led->lock);
 213
 214         ret = lp8860_fault_check(led);
 215         if (ret) {
 216                 dev_err(&led->client->dev, "Cannot read/clear faults\n");
 217                 goto out;
 218         }
 219
 220         ret = regmap_write(led->regmap, LP8860_DISP_CL1_BRT_MSB,
 221                         (disp_brightness & 0xff00) >> 8);
 222         if (ret) {
 223                 dev_err(&led->client->dev, "Cannot write CL1 MSB\n");
 224                 goto out;
 225         }
 226
 227         ret = regmap_write(led->regmap, LP8860_DISP_CL1_BRT_LSB,
 228                         disp_brightness & 0xff);
 229         if (ret) {
 230                 dev_err(&led->client->dev, "Cannot write CL1 LSB\n");
 231                 goto out;
 232         }
 233 out:
 234         mutex_unlock(&led->lock);
 235         return ret;
 236 }
 237
 238 static int lp8860_init(struct lp8860_led *led)
 239 {
 240         unsigned int read_buf;
 241         int ret, i, reg_count;
 242
 243         if (led->regulator) {
 244                 ret = regulator_enable(led->regulator);
 245                 if (ret) {
 246                         dev_err(&led->client->dev,
 247                                 "Failed to enable regulator\n");
 248                         return ret;
 249                 }
 250         }
 251
 252         gpiod_direction_output(led->enable_gpio, 1);
 253
 254         ret = lp8860_fault_check(led);
 255         if (ret)
 256                 goto out;
 257
 258         ret = regmap_read(led->regmap, LP8860_STATUS, &read_buf);
 259         if (ret)
 260                 goto out;
 261
 262         ret = lp8860_unlock_eeprom(led, LP8860_UNLOCK_EEPROM);
 263         if (ret) {
 264                 dev_err(&led->client->dev, "Failed unlocking EEPROM\n");
 265                 goto out;
 266         }
 267
 268         reg_count = ARRAY_SIZE(lp8860_eeprom_disp_regs) / sizeof(lp8860_eeprom_disp_regs[0]);
 269         for (i = 0; i < reg_count; i++) {
 270                 ret = regmap_write(led->eeprom_regmap,
 271                                 lp8860_eeprom_disp_regs[i].reg,
 272                                 lp8860_eeprom_disp_regs[i].value);
 273                 if (ret) {
 274                         dev_err(&led->client->dev, "Failed writing EEPROM\n");
 275                         goto out;
 276                 }
 277         }
 278
 279         ret = lp8860_unlock_eeprom(led, LP8860_LOCK_EEPROM);
 280         if (ret)
 281                 goto out;
 282
 283         ret = regmap_write(led->regmap,
 284                         LP8860_EEPROM_CNTRL,
 285                         LP8860_PROGRAM_EEPROM);
 286         if (ret) {
 287                 dev_err(&led->client->dev, "Failed programming EEPROM\n");
 288                 goto out;
 289         }
 290
 291         return ret;
 292
 293 out:
 294         if (ret)
 295                 gpiod_direction_output(led->enable_gpio, 0);
 296
 297         if (led->regulator) {
 298                 ret = regulator_disable(led->regulator);
 299                 if (ret)
 300                         dev_err(&led->client->dev,
 301                                 "Failed to disable regulator\n");
 302         }
 303
 304         return ret;
 305 }
 306
 307 static const struct reg_default lp8860_reg_defs[] = {
 308         { LP8860_DISP_CL1_BRT_MSB, 0x00},
 309         { LP8860_DISP_CL1_BRT_LSB, 0x00},
 310         { LP8860_DISP_CL1_CURR_MSB, 0x00},
 311         { LP8860_DISP_CL1_CURR_LSB, 0x00},
 312         { LP8860_CL2_BRT_MSB, 0x00},
 313         { LP8860_CL2_BRT_LSB, 0x00},
 314         { LP8860_CL2_CURRENT, 0x00},
 315         { LP8860_CL3_BRT_MSB, 0x00},
 316         { LP8860_CL3_BRT_LSB, 0x00},
 317         { LP8860_CL3_CURRENT, 0x00},
 318         { LP8860_CL4_BRT_MSB, 0x00},
 319         { LP8860_CL4_BRT_LSB, 0x00},
 320         { LP8860_CL4_CURRENT, 0x00},
 321         { LP8860_CONFIG, 0x00},
 322         { LP8860_FAULT_CLEAR, 0x00},
 323         { LP8860_EEPROM_CNTRL, 0x80},
 324         { LP8860_EEPROM_UNLOCK, 0x00},
 325 };
 326
 327 static const struct regmap_config lp8860_regmap_config = {
 328         .reg_bits = 8,
 329         .val_bits = 8,
 330
 331         .max_register = LP8860_EEPROM_UNLOCK,
 332         .reg_defaults = lp8860_reg_defs,
 333         .num_reg_defaults = ARRAY_SIZE(lp8860_reg_defs),
 334         .cache_type = REGCACHE_NONE,
 335 };
 336
 337 static const struct reg_default lp8860_eeprom_defs[] = {
 338         { LP8860_EEPROM_REG_0, 0x00 },
 339         { LP8860_EEPROM_REG_1, 0x00 },
 340         { LP8860_EEPROM_REG_2, 0x00 },
 341         { LP8860_EEPROM_REG_3, 0x00 },
 342         { LP8860_EEPROM_REG_4, 0x00 },
 343         { LP8860_EEPROM_REG_5, 0x00 },
 344         { LP8860_EEPROM_REG_6, 0x00 },
 345         { LP8860_EEPROM_REG_7, 0x00 },
 346         { LP8860_EEPROM_REG_8, 0x00 },
 347         { LP8860_EEPROM_REG_9, 0x00 },
 348         { LP8860_EEPROM_REG_10, 0x00 },
 349         { LP8860_EEPROM_REG_11, 0x00 },
 350         { LP8860_EEPROM_REG_12, 0x00 },
 351         { LP8860_EEPROM_REG_13, 0x00 },
 352         { LP8860_EEPROM_REG_14, 0x00 },
 353         { LP8860_EEPROM_REG_15, 0x00 },
 354         { LP8860_EEPROM_REG_16, 0x00 },
 355         { LP8860_EEPROM_REG_17, 0x00 },
 356         { LP8860_EEPROM_REG_18, 0x00 },
 357         { LP8860_EEPROM_REG_19, 0x00 },
 358         { LP8860_EEPROM_REG_20, 0x00 },
 359         { LP8860_EEPROM_REG_21, 0x00 },
 360         { LP8860_EEPROM_REG_22, 0x00 },
 361         { LP8860_EEPROM_REG_23, 0x00 },
 362         { LP8860_EEPROM_REG_24, 0x00 },
 363 };
 364
 365 static const struct regmap_config lp8860_eeprom_regmap_config = {
 366         .reg_bits = 8,
 367         .val_bits = 8,
 368
 369         .max_register = LP8860_EEPROM_REG_24,
 370         .reg_defaults = lp8860_eeprom_defs,
 371         .num_reg_defaults = ARRAY_SIZE(lp8860_eeprom_defs),
 372         .cache_type = REGCACHE_NONE,
 373 };
 374
 375 static int lp8860_probe(struct i2c_client *client)
 376 {
 377         int ret;
 378         struct lp8860_led *led;
 379         struct device_node *np = dev_of_node(&client->dev);
 380         struct device_node *child_node;
 381         struct led_init_data init_data = {};
 382
 383         led = devm_kzalloc(&client->dev, sizeof(*led), GFP_KERNEL);
 384         if (!led)
 385                 return -ENOMEM;
 386
 387         child_node = of_get_next_available_child(np, NULL);
 388         if (!child_node)
 389                 return -EINVAL;
 390
 391         led->enable_gpio = devm_gpiod_get_optional(&client->dev,
 392                                                    "enable", GPIOD_OUT_LOW);
 393         if (IS_ERR(led->enable_gpio)) {
 394                 ret = PTR_ERR(led->enable_gpio);
 395                 dev_err(&client->dev, "Failed to get enable gpio: %d\n", ret);
 396                 return ret;
 397         }
 398
 399         led->regulator = devm_regulator_get(&client->dev, "vled");
 400         if (IS_ERR(led->regulator))
 401                 led->regulator = NULL;
 402
 403         led->client = client;
 404         led->led_dev.brightness_set_blocking = lp8860_brightness_set;
 405
 406         mutex_init(&led->lock);
 407
 408         i2c_set_clientdata(client, led);
 409
 410         led->regmap = devm_regmap_init_i2c(client, &lp8860_regmap_config);
 411         if (IS_ERR(led->regmap)) {
 412                 ret = PTR_ERR(led->regmap);
 413                 dev_err(&client->dev, "Failed to allocate register map: %d\n",
 414                         ret);
 415                 return ret;
 416         }
 417
 418         led->eeprom_regmap = devm_regmap_init_i2c(client, &lp8860_eeprom_regmap_config);
 419         if (IS_ERR(led->eeprom_regmap)) {
 420                 ret = PTR_ERR(led->eeprom_regmap);
 421                 dev_err(&client->dev, "Failed to allocate register map: %d\n",
 422                         ret);
 423                 return ret;
 424         }
 425
 426         ret = lp8860_init(led);
 427         if (ret)
 428                 return ret;
 429
 430         init_data.fwnode = of_fwnode_handle(child_node);
 431         init_data.devicename = LP8860_NAME;
 432         init_data.default_label = ":display_cluster";
 433
 434         ret = devm_led_classdev_register_ext(&client->dev, &led->led_dev,
 435                                              &init_data);
 436         if (ret) {
 437                 dev_err(&client->dev, "led register err: %d\n", ret);
 438                 return ret;
 439         }
 440
 441         return 0;
 442 }
 443
 444 static void lp8860_remove(struct i2c_client *client)
 445 {
 446         struct lp8860_led *led = i2c_get_clientdata(client);
 447         int ret;
 448
 449         gpiod_direction_output(led->enable_gpio, 0);
 450
 451         if (led->regulator) {
 452                 ret = regulator_disable(led->regulator);
 453                 if (ret)
 454                         dev_err(&led->client->dev,
 455                                 "Failed to disable regulator\n");
 456         }
 457
 458         mutex_destroy(&led->lock);
 459 }
 460
 461 static const struct i2c_device_id lp8860_id[] = {
 462         { "lp8860" },
 463         { }
 464 };
 465 MODULE_DEVICE_TABLE(i2c, lp8860_id);
 466
 467 static const struct of_device_id of_lp8860_leds_match[] = {
 468         { .compatible = "ti,lp8860", },
 469         {},
 470 };
 471 MODULE_DEVICE_TABLE(of, of_lp8860_leds_match);
 472
 473 static struct i2c_driver lp8860_driver = {
 474         .driver = {
 475                 .name   = "lp8860",
 476                 .of_match_table = of_lp8860_leds_match,
 477         },
 478         .probe          = lp8860_probe,
 479         .remove         = lp8860_remove,
 480         .id_table       = lp8860_id,
 481 };
 482 module_i2c_driver(lp8860_driver);
 483
 484 MODULE_DESCRIPTION("Texas Instruments LP8860 LED driver");
 485 MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
 486 MODULE_LICENSE("GPL v2");