drivers/leds/leds-lp8860.c

   1 /*
   2  * TI LP8860 4-Channel LED Driver
   3  *
   4  * Copyright (C) 2014 Texas Instruments
   5  *
   6  * Author: Dan Murphy <dmurphy@ti.com>
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License
  10  * version 2 as published by the Free Software Foundation.
  11  *
  12  */
  13
  14 #include <linux/i2c.h>
  15 #include <linux/init.h>
  16 #include <linux/leds.h>
  17 #include <linux/regmap.h>
  18 #include <linux/regulator/consumer.h>
  19 #include <linux/module.h>
  20 #include <linux/mutex.h>
  21 #include <linux/of.h>
  22 #include <linux/of_gpio.h>
  23 #include <linux/gpio/consumer.h>
  24 #include <linux/slab.h>
  25
  26 #define LP8860_DISP_CL1_BRT_MSB         0x00
  27 #define LP8860_DISP_CL1_BRT_LSB         0x01
  28 #define LP8860_DISP_CL1_CURR_MSB        0x02
  29 #define LP8860_DISP_CL1_CURR_LSB        0x03
  30 #define LP8860_CL2_BRT_MSB              0x04
  31 #define LP8860_CL2_BRT_LSB              0x05
  32 #define LP8860_CL2_CURRENT              0x06
  33 #define LP8860_CL3_BRT_MSB              0x07
  34 #define LP8860_CL3_BRT_LSB              0x08
  35 #define LP8860_CL3_CURRENT              0x09
  36 #define LP8860_CL4_BRT_MSB              0x0a
  37 #define LP8860_CL4_BRT_LSB              0x0b
  38 #define LP8860_CL4_CURRENT              0x0c
  39 #define LP8860_CONFIG                   0x0d
  40 #define LP8860_STATUS                   0x0e
  41 #define LP8860_FAULT                    0x0f
  42 #define LP8860_LED_FAULT                0x10
  43 #define LP8860_FAULT_CLEAR              0x11
  44 #define LP8860_ID                       0x12
  45 #define LP8860_TEMP_MSB                 0x13
  46 #define LP8860_TEMP_LSB                 0x14
  47 #define LP8860_DISP_LED_CURR_MSB        0x15
  48 #define LP8860_DISP_LED_CURR_LSB        0x16
  49 #define LP8860_DISP_LED_PWM_MSB         0x17
  50 #define LP8860_DISP_LED_PWM_LSB         0x18
  51 #define LP8860_EEPROM_CNTRL             0x19
  52 #define LP8860_EEPROM_UNLOCK            0x1a
  53
  54 #define LP8860_EEPROM_REG_0             0x60
  55 #define LP8860_EEPROM_REG_1             0x61
  56 #define LP8860_EEPROM_REG_2             0x62
  57 #define LP8860_EEPROM_REG_3             0x63
  58 #define LP8860_EEPROM_REG_4             0x64
  59 #define LP8860_EEPROM_REG_5             0x65
  60 #define LP8860_EEPROM_REG_6             0x66
  61 #define LP8860_EEPROM_REG_7             0x67
  62 #define LP8860_EEPROM_REG_8             0x68
  63 #define LP8860_EEPROM_REG_9             0x69
  64 #define LP8860_EEPROM_REG_10            0x6a
  65 #define LP8860_EEPROM_REG_11            0x6b
  66 #define LP8860_EEPROM_REG_12            0x6c
  67 #define LP8860_EEPROM_REG_13            0x6d
  68 #define LP8860_EEPROM_REG_14            0x6e
  69 #define LP8860_EEPROM_REG_15            0x6f
  70 #define LP8860_EEPROM_REG_16            0x70
  71 #define LP8860_EEPROM_REG_17            0x71
  72 #define LP8860_EEPROM_REG_18            0x72
  73 #define LP8860_EEPROM_REG_19            0x73
  74 #define LP8860_EEPROM_REG_20            0x74
  75 #define LP8860_EEPROM_REG_21            0x75
  76 #define LP8860_EEPROM_REG_22            0x76
  77 #define LP8860_EEPROM_REG_23            0x77
  78 #define LP8860_EEPROM_REG_24            0x78
  79
  80 #define LP8860_LOCK_EEPROM              0x00
  81 #define LP8860_UNLOCK_EEPROM            0x01
  82 #define LP8860_PROGRAM_EEPROM           0x02
  83 #define LP8860_EEPROM_CODE_1            0x08
  84 #define LP8860_EEPROM_CODE_2            0xba
  85 #define LP8860_EEPROM_CODE_3            0xef
  86
  87 #define LP8860_CLEAR_FAULTS             0x01
  88
  89 #define LP8860_DISP_LED_NAME            "display_cluster"
  90
  91 /**
  92  * struct lp8860_led -
  93  * @lock - Lock for reading/writing the device
  94  * @client - Pointer to the I2C client
  95  * @led_dev - led class device pointer
  96  * @regmap - Devices register map
  97  * @eeprom_regmap - EEPROM register map
  98  * @enable_gpio - VDDIO/EN gpio to enable communication interface
  99  * @regulator - LED supply regulator pointer
 100  * @label - LED label
 101 **/
 102 struct lp8860_led {
 103         struct mutex lock;
 104         struct i2c_client *client;
 105         struct led_classdev led_dev;
 106         struct regmap *regmap;
 107         struct regmap *eeprom_regmap;
 108         struct gpio_desc *enable_gpio;
 109         struct regulator *regulator;
 110         const char *label;
 111 };
 112
 113 struct lp8860_eeprom_reg {
 114         uint8_t reg;
 115         uint8_t value;
 116 };
 117
 118 static struct lp8860_eeprom_reg lp8860_eeprom_disp_regs[] = {
 119         { LP8860_EEPROM_REG_0, 0xed },
 120         { LP8860_EEPROM_REG_1, 0xdf },
 121         { LP8860_EEPROM_REG_2, 0xdc },
 122         { LP8860_EEPROM_REG_3, 0xf0 },
 123         { LP8860_EEPROM_REG_4, 0xdf },
 124         { LP8860_EEPROM_REG_5, 0xe5 },
 125         { LP8860_EEPROM_REG_6, 0xf2 },
 126         { LP8860_EEPROM_REG_7, 0x77 },
 127         { LP8860_EEPROM_REG_8, 0x77 },
 128         { LP8860_EEPROM_REG_9, 0x71 },
 129         { LP8860_EEPROM_REG_10, 0x3f },
 130         { LP8860_EEPROM_REG_11, 0xb7 },
 131         { LP8860_EEPROM_REG_12, 0x17 },
 132         { LP8860_EEPROM_REG_13, 0xef },
 133         { LP8860_EEPROM_REG_14, 0xb0 },
 134         { LP8860_EEPROM_REG_15, 0x87 },
 135         { LP8860_EEPROM_REG_16, 0xce },
 136         { LP8860_EEPROM_REG_17, 0x72 },
 137         { LP8860_EEPROM_REG_18, 0xe5 },
 138         { LP8860_EEPROM_REG_19, 0xdf },
 139         { LP8860_EEPROM_REG_20, 0x35 },
 140         { LP8860_EEPROM_REG_21, 0x06 },
 141         { LP8860_EEPROM_REG_22, 0xdc },
 142         { LP8860_EEPROM_REG_23, 0x88 },
 143         { LP8860_EEPROM_REG_24, 0x3E },
 144 };
 145
 146 static int lp8860_unlock_eeprom(struct lp8860_led *led, int lock)
 147 {
 148         int ret;
 149
 150         mutex_lock(&led->lock);
 151
 152         if (lock == LP8860_UNLOCK_EEPROM) {
 153                 ret = regmap_write(led->regmap,
 154                         LP8860_EEPROM_UNLOCK,
 155                         LP8860_EEPROM_CODE_1);
 156                 if (ret) {
 157                         dev_err(&led->client->dev, "EEPROM Unlock failed\n");
 158                         goto out;
 159                 }
 160
 161                 ret = regmap_write(led->regmap,
 162                         LP8860_EEPROM_UNLOCK,
 163                         LP8860_EEPROM_CODE_2);
 164                 if (ret) {
 165                         dev_err(&led->client->dev, "EEPROM Unlock failed\n");
 166                         goto out;
 167                 }
 168                 ret = regmap_write(led->regmap,
 169                         LP8860_EEPROM_UNLOCK,
 170                         LP8860_EEPROM_CODE_3);
 171                 if (ret) {
 172                         dev_err(&led->client->dev, "EEPROM Unlock failed\n");
 173                         goto out;
 174                 }
 175         } else {
 176                 ret = regmap_write(led->regmap,
 177                         LP8860_EEPROM_UNLOCK,
 178                         LP8860_LOCK_EEPROM);
 179         }
 180
 181 out:
 182         mutex_unlock(&led->lock);
 183         return ret;
 184 }
 185
 186 static int lp8860_fault_check(struct lp8860_led *led)
 187 {
 188         int ret, fault;
 189         unsigned int read_buf;
 190
 191         ret = regmap_read(led->regmap, LP8860_LED_FAULT, &read_buf);
 192         if (ret)
 193                 goto out;
 194
 195         fault = read_buf;
 196
 197         ret = regmap_read(led->regmap, LP8860_FAULT, &read_buf);
 198         if (ret)
 199                 goto out;
 200
 201         fault |= read_buf;
 202
 203         /* Attempt to clear any faults */
 204         if (fault)
 205                 ret = regmap_write(led->regmap, LP8860_FAULT_CLEAR,
 206                         LP8860_CLEAR_FAULTS);
 207 out:
 208         return ret;
 209 }
 210
 211 static int lp8860_brightness_set(struct led_classdev *led_cdev,
 212                                 enum led_brightness brt_val)
 213 {
 214         struct lp8860_led *led =
 215                         container_of(led_cdev, struct lp8860_led, led_dev);
 216         int disp_brightness = brt_val * 255;
 217         int ret;
 218
 219         mutex_lock(&led->lock);
 220
 221         ret = lp8860_fault_check(led);
 222         if (ret) {
 223                 dev_err(&led->client->dev, "Cannot read/clear faults\n");
 224                 goto out;
 225         }
 226
 227         ret = regmap_write(led->regmap, LP8860_DISP_CL1_BRT_MSB,
 228                         (disp_brightness & 0xff00) >> 8);
 229         if (ret) {
 230                 dev_err(&led->client->dev, "Cannot write CL1 MSB\n");
 231                 goto out;
 232         }
 233
 234         ret = regmap_write(led->regmap, LP8860_DISP_CL1_BRT_LSB,
 235                         disp_brightness & 0xff);
 236         if (ret) {
 237                 dev_err(&led->client->dev, "Cannot write CL1 LSB\n");
 238                 goto out;
 239         }
 240 out:
 241         mutex_unlock(&led->lock);
 242         return ret;
 243 }
 244
 245 static int lp8860_init(struct lp8860_led *led)
 246 {
 247         unsigned int read_buf;
 248         int ret, i, reg_count;
 249
 250         if (led->enable_gpio)
 251                 gpiod_direction_output(led->enable_gpio, 1);
 252
 253         ret = lp8860_fault_check(led);
 254         if (ret)
 255                 goto out;
 256
 257         ret = regmap_read(led->regmap, LP8860_STATUS, &read_buf);
 258         if (ret)
 259                 goto out;
 260
 261         ret = lp8860_unlock_eeprom(led, LP8860_UNLOCK_EEPROM);
 262         if (ret) {
 263                 dev_err(&led->client->dev, "Failed unlocking EEPROM\n");
 264                 goto out;
 265         }
 266
 267         reg_count = ARRAY_SIZE(lp8860_eeprom_disp_regs) / sizeof(lp8860_eeprom_disp_regs[0]);
 268         for (i = 0; i < reg_count; i++) {
 269                 ret = regmap_write(led->eeprom_regmap,
 270                                 lp8860_eeprom_disp_regs[i].reg,
 271                                 lp8860_eeprom_disp_regs[i].value);
 272                 if (ret) {
 273                         dev_err(&led->client->dev, "Failed writing EEPROM\n");
 274                         goto out;
 275                 }
 276         }
 277
 278         ret = lp8860_unlock_eeprom(led, LP8860_LOCK_EEPROM);
 279         if (ret)
 280                 goto out;
 281
 282         ret = regmap_write(led->regmap,
 283                         LP8860_EEPROM_CNTRL,
 284                         LP8860_PROGRAM_EEPROM);
 285         if (ret)
 286                 dev_err(&led->client->dev, "Failed programming EEPROM\n");
 287 out:
 288         if (ret)
 289                 if (led->enable_gpio)
 290                         gpiod_direction_output(led->enable_gpio, 0);
 291         return ret;
 292 }
 293
 294 static const struct reg_default lp8860_reg_defs[] = {
 295         { LP8860_DISP_CL1_BRT_MSB, 0x00},
 296         { LP8860_DISP_CL1_BRT_LSB, 0x00},
 297         { LP8860_DISP_CL1_CURR_MSB, 0x00},
 298         { LP8860_DISP_CL1_CURR_LSB, 0x00},
 299         { LP8860_CL2_BRT_MSB, 0x00},
 300         { LP8860_CL2_BRT_LSB, 0x00},
 301         { LP8860_CL2_CURRENT, 0x00},
 302         { LP8860_CL3_BRT_MSB, 0x00},
 303         { LP8860_CL3_BRT_LSB, 0x00},
 304         { LP8860_CL3_CURRENT, 0x00},
 305         { LP8860_CL4_BRT_MSB, 0x00},
 306         { LP8860_CL4_BRT_LSB, 0x00},
 307         { LP8860_CL4_CURRENT, 0x00},
 308         { LP8860_CONFIG, 0x00},
 309         { LP8860_FAULT_CLEAR, 0x00},
 310         { LP8860_EEPROM_CNTRL, 0x80},
 311         { LP8860_EEPROM_UNLOCK, 0x00},
 312 };
 313
 314 static const struct regmap_config lp8860_regmap_config = {
 315         .reg_bits = 8,
 316         .val_bits = 8,
 317
 318         .max_register = LP8860_EEPROM_UNLOCK,
 319         .reg_defaults = lp8860_reg_defs,
 320         .num_reg_defaults = ARRAY_SIZE(lp8860_reg_defs),
 321         .cache_type = REGCACHE_NONE,
 322 };
 323
 324 static const struct reg_default lp8860_eeprom_defs[] = {
 325         { LP8860_EEPROM_REG_0, 0x00 },
 326         { LP8860_EEPROM_REG_1, 0x00 },
 327         { LP8860_EEPROM_REG_2, 0x00 },
 328         { LP8860_EEPROM_REG_3, 0x00 },
 329         { LP8860_EEPROM_REG_4, 0x00 },
 330         { LP8860_EEPROM_REG_5, 0x00 },
 331         { LP8860_EEPROM_REG_6, 0x00 },
 332         { LP8860_EEPROM_REG_7, 0x00 },
 333         { LP8860_EEPROM_REG_8, 0x00 },
 334         { LP8860_EEPROM_REG_9, 0x00 },
 335         { LP8860_EEPROM_REG_10, 0x00 },
 336         { LP8860_EEPROM_REG_11, 0x00 },
 337         { LP8860_EEPROM_REG_12, 0x00 },
 338         { LP8860_EEPROM_REG_13, 0x00 },
 339         { LP8860_EEPROM_REG_14, 0x00 },
 340         { LP8860_EEPROM_REG_15, 0x00 },
 341         { LP8860_EEPROM_REG_16, 0x00 },
 342         { LP8860_EEPROM_REG_17, 0x00 },
 343         { LP8860_EEPROM_REG_18, 0x00 },
 344         { LP8860_EEPROM_REG_19, 0x00 },
 345         { LP8860_EEPROM_REG_20, 0x00 },
 346         { LP8860_EEPROM_REG_21, 0x00 },
 347         { LP8860_EEPROM_REG_22, 0x00 },
 348         { LP8860_EEPROM_REG_23, 0x00 },
 349         { LP8860_EEPROM_REG_24, 0x00 },
 350 };
 351
 352 static const struct regmap_config lp8860_eeprom_regmap_config = {
 353         .reg_bits = 8,
 354         .val_bits = 8,
 355
 356         .max_register = LP8860_EEPROM_REG_24,
 357         .reg_defaults = lp8860_eeprom_defs,
 358         .num_reg_defaults = ARRAY_SIZE(lp8860_eeprom_defs),
 359         .cache_type = REGCACHE_NONE,
 360 };
 361
 362 static int lp8860_probe(struct i2c_client *client,
 363                         const struct i2c_device_id *id)
 364 {
 365         int ret;
 366         struct lp8860_led *led;
 367         struct device_node *np = client->dev.of_node;
 368
 369         led = devm_kzalloc(&client->dev, sizeof(*led), GFP_KERNEL);
 370         if (!led)
 371                 return -ENOMEM;
 372
 373         led->label = LP8860_DISP_LED_NAME;
 374
 375         if (client->dev.of_node) {
 376                 ret = of_property_read_string(np, "label", &led->label);
 377                 if (ret) {
 378                         dev_err(&client->dev, "Missing label in dt\n");
 379                         return -EINVAL;
 380                 }
 381         }
 382
 383         led->enable_gpio = devm_gpiod_get_optional(&client->dev,
 384                                                    "enable", GPIOD_OUT_LOW);
 385         if (IS_ERR(led->enable_gpio)) {
 386                 ret = PTR_ERR(led->enable_gpio);
 387                 dev_err(&client->dev, "Failed to get enable gpio: %d\n", ret);
 388                 return ret;
 389         }
 390
 391         led->regulator = devm_regulator_get(&client->dev, "vled");
 392         if (IS_ERR(led->regulator))
 393                 led->regulator = NULL;
 394
 395         led->client = client;
 396         led->led_dev.name = led->label;
 397         led->led_dev.max_brightness = LED_FULL;
 398         led->led_dev.brightness_set_blocking = lp8860_brightness_set;
 399
 400         mutex_init(&led->lock);
 401
 402         i2c_set_clientdata(client, led);
 403
 404         led->regmap = devm_regmap_init_i2c(client, &lp8860_regmap_config);
 405         if (IS_ERR(led->regmap)) {
 406                 ret = PTR_ERR(led->regmap);
 407                 dev_err(&client->dev, "Failed to allocate register map: %d\n",
 408                         ret);
 409                 return ret;
 410         }
 411
 412         led->eeprom_regmap = devm_regmap_init_i2c(client, &lp8860_eeprom_regmap_config);
 413         if (IS_ERR(led->eeprom_regmap)) {
 414                 ret = PTR_ERR(led->eeprom_regmap);
 415                 dev_err(&client->dev, "Failed to allocate register map: %d\n",
 416                         ret);
 417                 return ret;
 418         }
 419
 420         ret = lp8860_init(led);
 421         if (ret)
 422                 return ret;
 423
 424         ret = led_classdev_register(&client->dev, &led->led_dev);
 425         if (ret) {
 426                 dev_err(&client->dev, "led register err: %d\n", ret);
 427                 return ret;
 428         }
 429
 430         return 0;
 431 }
 432
 433 static int lp8860_remove(struct i2c_client *client)
 434 {
 435         struct lp8860_led *led = i2c_get_clientdata(client);
 436         int ret;
 437
 438         led_classdev_unregister(&led->led_dev);
 439
 440         if (led->enable_gpio)
 441                 gpiod_direction_output(led->enable_gpio, 0);
 442
 443         if (led->regulator) {
 444                 ret = regulator_disable(led->regulator);
 445                 if (ret)
 446                         dev_err(&led->client->dev,
 447                                 "Failed to disable regulator\n");
 448         }
 449
 450         return 0;
 451 }
 452
 453 static const struct i2c_device_id lp8860_id[] = {
 454         { "lp8860", 0 },
 455         { }
 456 };
 457 MODULE_DEVICE_TABLE(i2c, lp8860_id);
 458
 459 #ifdef CONFIG_OF
 460 static const struct of_device_id of_lp8860_leds_match[] = {
 461         { .compatible = "ti,lp8860", },
 462         {},
 463 };
 464 MODULE_DEVICE_TABLE(of, of_lp8860_leds_match);
 465 #endif
 466
 467 static struct i2c_driver lp8860_driver = {
 468         .driver = {
 469                 .name   = "lp8860",
 470                 .of_match_table = of_match_ptr(of_lp8860_leds_match),
 471         },
 472         .probe          = lp8860_probe,
 473         .remove         = lp8860_remove,
 474         .id_table       = lp8860_id,
 475 };
 476 module_i2c_driver(lp8860_driver);
 477
 478 MODULE_DESCRIPTION("Texas Instruments LP8860 LED driver");
 479 MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
 480 MODULE_LICENSE("GPL");