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/of_gpio.h>
  19 #include <linux/gpio/consumer.h>
  20 #include <linux/slab.h>
  21 #include <uapi/linux/uleds.h>
  22
  23 #define LP8860_DISP_CL1_BRT_MSB         0x00
  24 #define LP8860_DISP_CL1_BRT_LSB         0x01
  25 #define LP8860_DISP_CL1_CURR_MSB        0x02
  26 #define LP8860_DISP_CL1_CURR_LSB        0x03
  27 #define LP8860_CL2_BRT_MSB              0x04
  28 #define LP8860_CL2_BRT_LSB              0x05
  29 #define LP8860_CL2_CURRENT              0x06
  30 #define LP8860_CL3_BRT_MSB              0x07
  31 #define LP8860_CL3_BRT_LSB              0x08
  32 #define LP8860_CL3_CURRENT              0x09
  33 #define LP8860_CL4_BRT_MSB              0x0a
  34 #define LP8860_CL4_BRT_LSB              0x0b
  35 #define LP8860_CL4_CURRENT              0x0c
  36 #define LP8860_CONFIG                   0x0d
  37 #define LP8860_STATUS                   0x0e
  38 #define LP8860_FAULT                    0x0f
  39 #define LP8860_LED_FAULT                0x10
  40 #define LP8860_FAULT_CLEAR              0x11
  41 #define LP8860_ID                       0x12
  42 #define LP8860_TEMP_MSB                 0x13
  43 #define LP8860_TEMP_LSB                 0x14
  44 #define LP8860_DISP_LED_CURR_MSB        0x15
  45 #define LP8860_DISP_LED_CURR_LSB        0x16
  46 #define LP8860_DISP_LED_PWM_MSB         0x17
  47 #define LP8860_DISP_LED_PWM_LSB         0x18
  48 #define LP8860_EEPROM_CNTRL             0x19
  49 #define LP8860_EEPROM_UNLOCK            0x1a
  50
  51 #define LP8860_EEPROM_REG_0             0x60
  52 #define LP8860_EEPROM_REG_1             0x61
  53 #define LP8860_EEPROM_REG_2             0x62
  54 #define LP8860_EEPROM_REG_3             0x63
  55 #define LP8860_EEPROM_REG_4             0x64
  56 #define LP8860_EEPROM_REG_5             0x65
  57 #define LP8860_EEPROM_REG_6             0x66
  58 #define LP8860_EEPROM_REG_7             0x67
  59 #define LP8860_EEPROM_REG_8             0x68
  60 #define LP8860_EEPROM_REG_9             0x69
  61 #define LP8860_EEPROM_REG_10            0x6a
  62 #define LP8860_EEPROM_REG_11            0x6b
  63 #define LP8860_EEPROM_REG_12            0x6c
  64 #define LP8860_EEPROM_REG_13            0x6d
  65 #define LP8860_EEPROM_REG_14            0x6e
  66 #define LP8860_EEPROM_REG_15            0x6f
  67 #define LP8860_EEPROM_REG_16            0x70
  68 #define LP8860_EEPROM_REG_17            0x71
  69 #define LP8860_EEPROM_REG_18            0x72
  70 #define LP8860_EEPROM_REG_19            0x73
  71 #define LP8860_EEPROM_REG_20            0x74
  72 #define LP8860_EEPROM_REG_21            0x75
  73 #define LP8860_EEPROM_REG_22            0x76
  74 #define LP8860_EEPROM_REG_23            0x77
  75 #define LP8860_EEPROM_REG_24            0x78
  76
  77 #define LP8860_LOCK_EEPROM              0x00
  78 #define LP8860_UNLOCK_EEPROM            0x01
  79 #define LP8860_PROGRAM_EEPROM           0x02
  80 #define LP8860_EEPROM_CODE_1            0x08
  81 #define LP8860_EEPROM_CODE_2            0xba
  82 #define LP8860_EEPROM_CODE_3            0xef
  83
  84 #define LP8860_CLEAR_FAULTS             0x01
  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  * @label - LED label
  96  */
  97 struct lp8860_led {
  98         struct mutex lock;
  99         struct i2c_client *client;
 100         struct led_classdev led_dev;
 101         struct regmap *regmap;
 102         struct regmap *eeprom_regmap;
 103         struct gpio_desc *enable_gpio;
 104         struct regulator *regulator;
 105         char label[LED_MAX_NAME_SIZE];
 106 };
 107
 108 struct lp8860_eeprom_reg {
 109         uint8_t reg;
 110         uint8_t value;
 111 };
 112
 113 static struct lp8860_eeprom_reg lp8860_eeprom_disp_regs[] = {
 114         { LP8860_EEPROM_REG_0, 0xed },
 115         { LP8860_EEPROM_REG_1, 0xdf },
 116         { LP8860_EEPROM_REG_2, 0xdc },
 117         { LP8860_EEPROM_REG_3, 0xf0 },
 118         { LP8860_EEPROM_REG_4, 0xdf },
 119         { LP8860_EEPROM_REG_5, 0xe5 },
 120         { LP8860_EEPROM_REG_6, 0xf2 },
 121         { LP8860_EEPROM_REG_7, 0x77 },
 122         { LP8860_EEPROM_REG_8, 0x77 },
 123         { LP8860_EEPROM_REG_9, 0x71 },
 124         { LP8860_EEPROM_REG_10, 0x3f },
 125         { LP8860_EEPROM_REG_11, 0xb7 },
 126         { LP8860_EEPROM_REG_12, 0x17 },
 127         { LP8860_EEPROM_REG_13, 0xef },
 128         { LP8860_EEPROM_REG_14, 0xb0 },
 129         { LP8860_EEPROM_REG_15, 0x87 },
 130         { LP8860_EEPROM_REG_16, 0xce },
 131         { LP8860_EEPROM_REG_17, 0x72 },
 132         { LP8860_EEPROM_REG_18, 0xe5 },
 133         { LP8860_EEPROM_REG_19, 0xdf },
 134         { LP8860_EEPROM_REG_20, 0x35 },
 135         { LP8860_EEPROM_REG_21, 0x06 },
 136         { LP8860_EEPROM_REG_22, 0xdc },
 137         { LP8860_EEPROM_REG_23, 0x88 },
 138         { LP8860_EEPROM_REG_24, 0x3E },
 139 };
 140
 141 static int lp8860_unlock_eeprom(struct lp8860_led *led, int lock)
 142 {
 143         int ret;
 144
 145         mutex_lock(&led->lock);
 146
 147         if (lock == LP8860_UNLOCK_EEPROM) {
 148                 ret = regmap_write(led->regmap,
 149                         LP8860_EEPROM_UNLOCK,
 150                         LP8860_EEPROM_CODE_1);
 151                 if (ret) {
 152                         dev_err(&led->client->dev, "EEPROM Unlock failed\n");
 153                         goto out;
 154                 }
 155
 156                 ret = regmap_write(led->regmap,
 157                         LP8860_EEPROM_UNLOCK,
 158                         LP8860_EEPROM_CODE_2);
 159                 if (ret) {
 160                         dev_err(&led->client->dev, "EEPROM Unlock failed\n");
 161                         goto out;
 162                 }
 163                 ret = regmap_write(led->regmap,
 164                         LP8860_EEPROM_UNLOCK,
 165                         LP8860_EEPROM_CODE_3);
 166                 if (ret) {
 167                         dev_err(&led->client->dev, "EEPROM Unlock failed\n");
 168                         goto out;
 169                 }
 170         } else {
 171                 ret = regmap_write(led->regmap,
 172                         LP8860_EEPROM_UNLOCK,
 173                         LP8860_LOCK_EEPROM);
 174         }
 175
 176 out:
 177         mutex_unlock(&led->lock);
 178         return ret;
 179 }
 180
 181 static int lp8860_fault_check(struct lp8860_led *led)
 182 {
 183         int ret, fault;
 184         unsigned int read_buf;
 185
 186         ret = regmap_read(led->regmap, LP8860_LED_FAULT, &read_buf);
 187         if (ret)
 188                 goto out;
 189
 190         fault = read_buf;
 191
 192         ret = regmap_read(led->regmap, LP8860_FAULT, &read_buf);
 193         if (ret)
 194                 goto out;
 195
 196         fault |= read_buf;
 197
 198         /* Attempt to clear any faults */
 199         if (fault)
 200                 ret = regmap_write(led->regmap, LP8860_FAULT_CLEAR,
 201                         LP8860_CLEAR_FAULTS);
 202 out:
 203         return ret;
 204 }
 205
 206 static int lp8860_brightness_set(struct led_classdev *led_cdev,
 207                                 enum led_brightness brt_val)
 208 {
 209         struct lp8860_led *led =
 210                         container_of(led_cdev, struct lp8860_led, led_dev);
 211         int disp_brightness = brt_val * 255;
 212         int ret;
 213
 214         mutex_lock(&led->lock);
 215
 216         ret = lp8860_fault_check(led);
 217         if (ret) {
 218                 dev_err(&led->client->dev, "Cannot read/clear faults\n");
 219                 goto out;
 220         }
 221
 222         ret = regmap_write(led->regmap, LP8860_DISP_CL1_BRT_MSB,
 223                         (disp_brightness & 0xff00) >> 8);
 224         if (ret) {
 225                 dev_err(&led->client->dev, "Cannot write CL1 MSB\n");
 226                 goto out;
 227         }
 228
 229         ret = regmap_write(led->regmap, LP8860_DISP_CL1_BRT_LSB,
 230                         disp_brightness & 0xff);
 231         if (ret) {
 232                 dev_err(&led->client->dev, "Cannot write CL1 LSB\n");
 233                 goto out;
 234         }
 235 out:
 236         mutex_unlock(&led->lock);
 237         return ret;
 238 }
 239
 240 static int lp8860_init(struct lp8860_led *led)
 241 {
 242         unsigned int read_buf;
 243         int ret, i, reg_count;
 244
 245         if (led->regulator) {
 246                 ret = regulator_enable(led->regulator);
 247                 if (ret) {
 248                         dev_err(&led->client->dev,
 249                                 "Failed to enable regulator\n");
 250                         return ret;
 251                 }
 252         }
 253
 254         if (led->enable_gpio)
 255                 gpiod_direction_output(led->enable_gpio, 1);
 256
 257         ret = lp8860_fault_check(led);
 258         if (ret)
 259                 goto out;
 260
 261         ret = regmap_read(led->regmap, LP8860_STATUS, &read_buf);
 262         if (ret)
 263                 goto out;
 264
 265         ret = lp8860_unlock_eeprom(led, LP8860_UNLOCK_EEPROM);
 266         if (ret) {
 267                 dev_err(&led->client->dev, "Failed unlocking EEPROM\n");
 268                 goto out;
 269         }
 270
 271         reg_count = ARRAY_SIZE(lp8860_eeprom_disp_regs) / sizeof(lp8860_eeprom_disp_regs[0]);
 272         for (i = 0; i < reg_count; i++) {
 273                 ret = regmap_write(led->eeprom_regmap,
 274                                 lp8860_eeprom_disp_regs[i].reg,
 275                                 lp8860_eeprom_disp_regs[i].value);
 276                 if (ret) {
 277                         dev_err(&led->client->dev, "Failed writing EEPROM\n");
 278                         goto out;
 279                 }
 280         }
 281
 282         ret = lp8860_unlock_eeprom(led, LP8860_LOCK_EEPROM);
 283         if (ret)
 284                 goto out;
 285
 286         ret = regmap_write(led->regmap,
 287                         LP8860_EEPROM_CNTRL,
 288                         LP8860_PROGRAM_EEPROM);
 289         if (ret) {
 290                 dev_err(&led->client->dev, "Failed programming EEPROM\n");
 291                 goto out;
 292         }
 293
 294         return ret;
 295
 296 out:
 297         if (ret)
 298                 if (led->enable_gpio)
 299                         gpiod_direction_output(led->enable_gpio, 0);
 300
 301         if (led->regulator) {
 302                 ret = regulator_disable(led->regulator);
 303                 if (ret)
 304                         dev_err(&led->client->dev,
 305                                 "Failed to disable regulator\n");
 306         }
 307
 308         return ret;
 309 }
 310
 311 static const struct reg_default lp8860_reg_defs[] = {
 312         { LP8860_DISP_CL1_BRT_MSB, 0x00},
 313         { LP8860_DISP_CL1_BRT_LSB, 0x00},
 314         { LP8860_DISP_CL1_CURR_MSB, 0x00},
 315         { LP8860_DISP_CL1_CURR_LSB, 0x00},
 316         { LP8860_CL2_BRT_MSB, 0x00},
 317         { LP8860_CL2_BRT_LSB, 0x00},
 318         { LP8860_CL2_CURRENT, 0x00},
 319         { LP8860_CL3_BRT_MSB, 0x00},
 320         { LP8860_CL3_BRT_LSB, 0x00},
 321         { LP8860_CL3_CURRENT, 0x00},
 322         { LP8860_CL4_BRT_MSB, 0x00},
 323         { LP8860_CL4_BRT_LSB, 0x00},
 324         { LP8860_CL4_CURRENT, 0x00},
 325         { LP8860_CONFIG, 0x00},
 326         { LP8860_FAULT_CLEAR, 0x00},
 327         { LP8860_EEPROM_CNTRL, 0x80},
 328         { LP8860_EEPROM_UNLOCK, 0x00},
 329 };
 330
 331 static const struct regmap_config lp8860_regmap_config = {
 332         .reg_bits = 8,
 333         .val_bits = 8,
 334
 335         .max_register = LP8860_EEPROM_UNLOCK,
 336         .reg_defaults = lp8860_reg_defs,
 337         .num_reg_defaults = ARRAY_SIZE(lp8860_reg_defs),
 338         .cache_type = REGCACHE_NONE,
 339 };
 340
 341 static const struct reg_default lp8860_eeprom_defs[] = {
 342         { LP8860_EEPROM_REG_0, 0x00 },
 343         { LP8860_EEPROM_REG_1, 0x00 },
 344         { LP8860_EEPROM_REG_2, 0x00 },
 345         { LP8860_EEPROM_REG_3, 0x00 },
 346         { LP8860_EEPROM_REG_4, 0x00 },
 347         { LP8860_EEPROM_REG_5, 0x00 },
 348         { LP8860_EEPROM_REG_6, 0x00 },
 349         { LP8860_EEPROM_REG_7, 0x00 },
 350         { LP8860_EEPROM_REG_8, 0x00 },
 351         { LP8860_EEPROM_REG_9, 0x00 },
 352         { LP8860_EEPROM_REG_10, 0x00 },
 353         { LP8860_EEPROM_REG_11, 0x00 },
 354         { LP8860_EEPROM_REG_12, 0x00 },
 355         { LP8860_EEPROM_REG_13, 0x00 },
 356         { LP8860_EEPROM_REG_14, 0x00 },
 357         { LP8860_EEPROM_REG_15, 0x00 },
 358         { LP8860_EEPROM_REG_16, 0x00 },
 359         { LP8860_EEPROM_REG_17, 0x00 },
 360         { LP8860_EEPROM_REG_18, 0x00 },
 361         { LP8860_EEPROM_REG_19, 0x00 },
 362         { LP8860_EEPROM_REG_20, 0x00 },
 363         { LP8860_EEPROM_REG_21, 0x00 },
 364         { LP8860_EEPROM_REG_22, 0x00 },
 365         { LP8860_EEPROM_REG_23, 0x00 },
 366         { LP8860_EEPROM_REG_24, 0x00 },
 367 };
 368
 369 static const struct regmap_config lp8860_eeprom_regmap_config = {
 370         .reg_bits = 8,
 371         .val_bits = 8,
 372
 373         .max_register = LP8860_EEPROM_REG_24,
 374         .reg_defaults = lp8860_eeprom_defs,
 375         .num_reg_defaults = ARRAY_SIZE(lp8860_eeprom_defs),
 376         .cache_type = REGCACHE_NONE,
 377 };
 378
 379 static int lp8860_probe(struct i2c_client *client,
 380                         const struct i2c_device_id *id)
 381 {
 382         int ret;
 383         struct lp8860_led *led;
 384         struct device_node *np = client->dev.of_node;
 385         struct device_node *child_node;
 386         const char *name;
 387
 388         led = devm_kzalloc(&client->dev, sizeof(*led), GFP_KERNEL);
 389         if (!led)
 390                 return -ENOMEM;
 391
 392         for_each_available_child_of_node(np, child_node) {
 393                 led->led_dev.default_trigger = of_get_property(child_node,
 394                                                     "linux,default-trigger",
 395                                                     NULL);
 396
 397                 ret = of_property_read_string(child_node, "label", &name);
 398                 if (!ret)
 399                         snprintf(led->label, sizeof(led->label), "%s:%s",
 400                                  id->name, name);
 401                 else
 402                         snprintf(led->label, sizeof(led->label),
 403                                 "%s::display_cluster", id->name);
 404         }
 405
 406         led->enable_gpio = devm_gpiod_get_optional(&client->dev,
 407                                                    "enable", GPIOD_OUT_LOW);
 408         if (IS_ERR(led->enable_gpio)) {
 409                 ret = PTR_ERR(led->enable_gpio);
 410                 dev_err(&client->dev, "Failed to get enable gpio: %d\n", ret);
 411                 return ret;
 412         }
 413
 414         led->regulator = devm_regulator_get(&client->dev, "vled");
 415         if (IS_ERR(led->regulator))
 416                 led->regulator = NULL;
 417
 418         led->client = client;
 419         led->led_dev.name = led->label;
 420         led->led_dev.brightness_set_blocking = lp8860_brightness_set;
 421
 422         mutex_init(&led->lock);
 423
 424         i2c_set_clientdata(client, led);
 425
 426         led->regmap = devm_regmap_init_i2c(client, &lp8860_regmap_config);
 427         if (IS_ERR(led->regmap)) {
 428                 ret = PTR_ERR(led->regmap);
 429                 dev_err(&client->dev, "Failed to allocate register map: %d\n",
 430                         ret);
 431                 return ret;
 432         }
 433
 434         led->eeprom_regmap = devm_regmap_init_i2c(client, &lp8860_eeprom_regmap_config);
 435         if (IS_ERR(led->eeprom_regmap)) {
 436                 ret = PTR_ERR(led->eeprom_regmap);
 437                 dev_err(&client->dev, "Failed to allocate register map: %d\n",
 438                         ret);
 439                 return ret;
 440         }
 441
 442         ret = lp8860_init(led);
 443         if (ret)
 444                 return ret;
 445
 446         ret = devm_led_classdev_register(&client->dev, &led->led_dev);
 447         if (ret) {
 448                 dev_err(&client->dev, "led register err: %d\n", ret);
 449                 return ret;
 450         }
 451
 452         return 0;
 453 }
 454
 455 static int lp8860_remove(struct i2c_client *client)
 456 {
 457         struct lp8860_led *led = i2c_get_clientdata(client);
 458         int ret;
 459
 460         if (led->enable_gpio)
 461                 gpiod_direction_output(led->enable_gpio, 0);
 462
 463         if (led->regulator) {
 464                 ret = regulator_disable(led->regulator);
 465                 if (ret)
 466                         dev_err(&led->client->dev,
 467                                 "Failed to disable regulator\n");
 468         }
 469
 470         mutex_destroy(&led->lock);
 471
 472         return 0;
 473 }
 474
 475 static const struct i2c_device_id lp8860_id[] = {
 476         { "lp8860", 0 },
 477         { }
 478 };
 479 MODULE_DEVICE_TABLE(i2c, lp8860_id);
 480
 481 static const struct of_device_id of_lp8860_leds_match[] = {
 482         { .compatible = "ti,lp8860", },
 483         {},
 484 };
 485 MODULE_DEVICE_TABLE(of, of_lp8860_leds_match);
 486
 487 static struct i2c_driver lp8860_driver = {
 488         .driver = {
 489                 .name   = "lp8860",
 490                 .of_match_table = of_lp8860_leds_match,
 491         },
 492         .probe          = lp8860_probe,
 493         .remove         = lp8860_remove,
 494         .id_table       = lp8860_id,
 495 };
 496 module_i2c_driver(lp8860_driver);
 497
 498 MODULE_DESCRIPTION("Texas Instruments LP8860 LED driver");
 499 MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
 500 MODULE_LICENSE("GPL v2");