linux/drivers/leds/leds-lp8860.c
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   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
  22#define LP8860_DISP_CL1_BRT_MSB         0x00
  23#define LP8860_DISP_CL1_BRT_LSB         0x01
  24#define LP8860_DISP_CL1_CURR_MSB        0x02
  25#define LP8860_DISP_CL1_CURR_LSB        0x03
  26#define LP8860_CL2_BRT_MSB              0x04
  27#define LP8860_CL2_BRT_LSB              0x05
  28#define LP8860_CL2_CURRENT              0x06
  29#define LP8860_CL3_BRT_MSB              0x07
  30#define LP8860_CL3_BRT_LSB              0x08
  31#define LP8860_CL3_CURRENT              0x09
  32#define LP8860_CL4_BRT_MSB              0x0a
  33#define LP8860_CL4_BRT_LSB              0x0b
  34#define LP8860_CL4_CURRENT              0x0c
  35#define LP8860_CONFIG                   0x0d
  36#define LP8860_STATUS                   0x0e
  37#define LP8860_FAULT                    0x0f
  38#define LP8860_LED_FAULT                0x10
  39#define LP8860_FAULT_CLEAR              0x11
  40#define LP8860_ID                       0x12
  41#define LP8860_TEMP_MSB                 0x13
  42#define LP8860_TEMP_LSB                 0x14
  43#define LP8860_DISP_LED_CURR_MSB        0x15
  44#define LP8860_DISP_LED_CURR_LSB        0x16
  45#define LP8860_DISP_LED_PWM_MSB         0x17
  46#define LP8860_DISP_LED_PWM_LSB         0x18
  47#define LP8860_EEPROM_CNTRL             0x19
  48#define LP8860_EEPROM_UNLOCK            0x1a
  49
  50#define LP8860_EEPROM_REG_0             0x60
  51#define LP8860_EEPROM_REG_1             0x61
  52#define LP8860_EEPROM_REG_2             0x62
  53#define LP8860_EEPROM_REG_3             0x63
  54#define LP8860_EEPROM_REG_4             0x64
  55#define LP8860_EEPROM_REG_5             0x65
  56#define LP8860_EEPROM_REG_6             0x66
  57#define LP8860_EEPROM_REG_7             0x67
  58#define LP8860_EEPROM_REG_8             0x68
  59#define LP8860_EEPROM_REG_9             0x69
  60#define LP8860_EEPROM_REG_10            0x6a
  61#define LP8860_EEPROM_REG_11            0x6b
  62#define LP8860_EEPROM_REG_12            0x6c
  63#define LP8860_EEPROM_REG_13            0x6d
  64#define LP8860_EEPROM_REG_14            0x6e
  65#define LP8860_EEPROM_REG_15            0x6f
  66#define LP8860_EEPROM_REG_16            0x70
  67#define LP8860_EEPROM_REG_17            0x71
  68#define LP8860_EEPROM_REG_18            0x72
  69#define LP8860_EEPROM_REG_19            0x73
  70#define LP8860_EEPROM_REG_20            0x74
  71#define LP8860_EEPROM_REG_21            0x75
  72#define LP8860_EEPROM_REG_22            0x76
  73#define LP8860_EEPROM_REG_23            0x77
  74#define LP8860_EEPROM_REG_24            0x78
  75
  76#define LP8860_LOCK_EEPROM              0x00
  77#define LP8860_UNLOCK_EEPROM            0x01
  78#define LP8860_PROGRAM_EEPROM           0x02
  79#define LP8860_EEPROM_CODE_1            0x08
  80#define LP8860_EEPROM_CODE_2            0xba
  81#define LP8860_EEPROM_CODE_3            0xef
  82
  83#define LP8860_CLEAR_FAULTS             0x01
  84
  85#define LP8860_NAME                     "lp8860"
  86
  87/**
  88 * struct lp8860_led
  89 * @lock: Lock for reading/writing the device
  90 * @client: Pointer to the I2C client
  91 * @led_dev: led class device pointer
  92 * @regmap: Devices register map
  93 * @eeprom_regmap: EEPROM register map
  94 * @enable_gpio: VDDIO/EN gpio to enable communication interface
  95 * @regulator: LED supply regulator pointer
  96 */
  97struct 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};
 106
 107struct lp8860_eeprom_reg {
 108        uint8_t reg;
 109        uint8_t value;
 110};
 111
 112static struct lp8860_eeprom_reg lp8860_eeprom_disp_regs[] = {
 113        { LP8860_EEPROM_REG_0, 0xed },
 114        { LP8860_EEPROM_REG_1, 0xdf },
 115        { LP8860_EEPROM_REG_2, 0xdc },
 116        { LP8860_EEPROM_REG_3, 0xf0 },
 117        { LP8860_EEPROM_REG_4, 0xdf },
 118        { LP8860_EEPROM_REG_5, 0xe5 },
 119        { LP8860_EEPROM_REG_6, 0xf2 },
 120        { LP8860_EEPROM_REG_7, 0x77 },
 121        { LP8860_EEPROM_REG_8, 0x77 },
 122        { LP8860_EEPROM_REG_9, 0x71 },
 123        { LP8860_EEPROM_REG_10, 0x3f },
 124        { LP8860_EEPROM_REG_11, 0xb7 },
 125        { LP8860_EEPROM_REG_12, 0x17 },
 126        { LP8860_EEPROM_REG_13, 0xef },
 127        { LP8860_EEPROM_REG_14, 0xb0 },
 128        { LP8860_EEPROM_REG_15, 0x87 },
 129        { LP8860_EEPROM_REG_16, 0xce },
 130        { LP8860_EEPROM_REG_17, 0x72 },
 131        { LP8860_EEPROM_REG_18, 0xe5 },
 132        { LP8860_EEPROM_REG_19, 0xdf },
 133        { LP8860_EEPROM_REG_20, 0x35 },
 134        { LP8860_EEPROM_REG_21, 0x06 },
 135        { LP8860_EEPROM_REG_22, 0xdc },
 136        { LP8860_EEPROM_REG_23, 0x88 },
 137        { LP8860_EEPROM_REG_24, 0x3E },
 138};
 139
 140static int lp8860_unlock_eeprom(struct lp8860_led *led, int lock)
 141{
 142        int ret;
 143
 144        mutex_lock(&led->lock);
 145
 146        if (lock == LP8860_UNLOCK_EEPROM) {
 147                ret = regmap_write(led->regmap,
 148                        LP8860_EEPROM_UNLOCK,
 149                        LP8860_EEPROM_CODE_1);
 150                if (ret) {
 151                        dev_err(&led->client->dev, "EEPROM Unlock failed\n");
 152                        goto out;
 153                }
 154
 155                ret = regmap_write(led->regmap,
 156                        LP8860_EEPROM_UNLOCK,
 157                        LP8860_EEPROM_CODE_2);
 158                if (ret) {
 159                        dev_err(&led->client->dev, "EEPROM Unlock failed\n");
 160                        goto out;
 161                }
 162                ret = regmap_write(led->regmap,
 163                        LP8860_EEPROM_UNLOCK,
 164                        LP8860_EEPROM_CODE_3);
 165                if (ret) {
 166                        dev_err(&led->client->dev, "EEPROM Unlock failed\n");
 167                        goto out;
 168                }
 169        } else {
 170                ret = regmap_write(led->regmap,
 171                        LP8860_EEPROM_UNLOCK,
 172                        LP8860_LOCK_EEPROM);
 173        }
 174
 175out:
 176        mutex_unlock(&led->lock);
 177        return ret;
 178}
 179
 180static int lp8860_fault_check(struct lp8860_led *led)
 181{
 182        int ret, fault;
 183        unsigned int read_buf;
 184
 185        ret = regmap_read(led->regmap, LP8860_LED_FAULT, &read_buf);
 186        if (ret)
 187                goto out;
 188
 189        fault = read_buf;
 190
 191        ret = regmap_read(led->regmap, LP8860_FAULT, &read_buf);
 192        if (ret)
 193                goto out;
 194
 195        fault |= read_buf;
 196
 197        /* Attempt to clear any faults */
 198        if (fault)
 199                ret = regmap_write(led->regmap, LP8860_FAULT_CLEAR,
 200                        LP8860_CLEAR_FAULTS);
 201out:
 202        return ret;
 203}
 204
 205static int lp8860_brightness_set(struct led_classdev *led_cdev,
 206                                enum led_brightness brt_val)
 207{
 208        struct lp8860_led *led =
 209                        container_of(led_cdev, struct lp8860_led, led_dev);
 210        int disp_brightness = brt_val * 255;
 211        int ret;
 212
 213        mutex_lock(&led->lock);
 214
 215        ret = lp8860_fault_check(led);
 216        if (ret) {
 217                dev_err(&led->client->dev, "Cannot read/clear faults\n");
 218                goto out;
 219        }
 220
 221        ret = regmap_write(led->regmap, LP8860_DISP_CL1_BRT_MSB,
 222                        (disp_brightness & 0xff00) >> 8);
 223        if (ret) {
 224                dev_err(&led->client->dev, "Cannot write CL1 MSB\n");
 225                goto out;
 226        }
 227
 228        ret = regmap_write(led->regmap, LP8860_DISP_CL1_BRT_LSB,
 229                        disp_brightness & 0xff);
 230        if (ret) {
 231                dev_err(&led->client->dev, "Cannot write CL1 LSB\n");
 232                goto out;
 233        }
 234out:
 235        mutex_unlock(&led->lock);
 236        return ret;
 237}
 238
 239static int lp8860_init(struct lp8860_led *led)
 240{
 241        unsigned int read_buf;
 242        int ret, i, reg_count;
 243
 244        if (led->regulator) {
 245                ret = regulator_enable(led->regulator);
 246                if (ret) {
 247                        dev_err(&led->client->dev,
 248                                "Failed to enable regulator\n");
 249                        return ret;
 250                }
 251        }
 252
 253        if (led->enable_gpio)
 254                gpiod_direction_output(led->enable_gpio, 1);
 255
 256        ret = lp8860_fault_check(led);
 257        if (ret)
 258                goto out;
 259
 260        ret = regmap_read(led->regmap, LP8860_STATUS, &read_buf);
 261        if (ret)
 262                goto out;
 263
 264        ret = lp8860_unlock_eeprom(led, LP8860_UNLOCK_EEPROM);
 265        if (ret) {
 266                dev_err(&led->client->dev, "Failed unlocking EEPROM\n");
 267                goto out;
 268        }
 269
 270        reg_count = ARRAY_SIZE(lp8860_eeprom_disp_regs) / sizeof(lp8860_eeprom_disp_regs[0]);
 271        for (i = 0; i < reg_count; i++) {
 272                ret = regmap_write(led->eeprom_regmap,
 273                                lp8860_eeprom_disp_regs[i].reg,
 274                                lp8860_eeprom_disp_regs[i].value);
 275                if (ret) {
 276                        dev_err(&led->client->dev, "Failed writing EEPROM\n");
 277                        goto out;
 278                }
 279        }
 280
 281        ret = lp8860_unlock_eeprom(led, LP8860_LOCK_EEPROM);
 282        if (ret)
 283                goto out;
 284
 285        ret = regmap_write(led->regmap,
 286                        LP8860_EEPROM_CNTRL,
 287                        LP8860_PROGRAM_EEPROM);
 288        if (ret) {
 289                dev_err(&led->client->dev, "Failed programming EEPROM\n");
 290                goto out;
 291        }
 292
 293        return ret;
 294
 295out:
 296        if (ret)
 297                if (led->enable_gpio)
 298                        gpiod_direction_output(led->enable_gpio, 0);
 299
 300        if (led->regulator) {
 301                ret = regulator_disable(led->regulator);
 302                if (ret)
 303                        dev_err(&led->client->dev,
 304                                "Failed to disable regulator\n");
 305        }
 306
 307        return ret;
 308}
 309
 310static const struct reg_default lp8860_reg_defs[] = {
 311        { LP8860_DISP_CL1_BRT_MSB, 0x00},
 312        { LP8860_DISP_CL1_BRT_LSB, 0x00},
 313        { LP8860_DISP_CL1_CURR_MSB, 0x00},
 314        { LP8860_DISP_CL1_CURR_LSB, 0x00},
 315        { LP8860_CL2_BRT_MSB, 0x00},
 316        { LP8860_CL2_BRT_LSB, 0x00},
 317        { LP8860_CL2_CURRENT, 0x00},
 318        { LP8860_CL3_BRT_MSB, 0x00},
 319        { LP8860_CL3_BRT_LSB, 0x00},
 320        { LP8860_CL3_CURRENT, 0x00},
 321        { LP8860_CL4_BRT_MSB, 0x00},
 322        { LP8860_CL4_BRT_LSB, 0x00},
 323        { LP8860_CL4_CURRENT, 0x00},
 324        { LP8860_CONFIG, 0x00},
 325        { LP8860_FAULT_CLEAR, 0x00},
 326        { LP8860_EEPROM_CNTRL, 0x80},
 327        { LP8860_EEPROM_UNLOCK, 0x00},
 328};
 329
 330static const struct regmap_config lp8860_regmap_config = {
 331        .reg_bits = 8,
 332        .val_bits = 8,
 333
 334        .max_register = LP8860_EEPROM_UNLOCK,
 335        .reg_defaults = lp8860_reg_defs,
 336        .num_reg_defaults = ARRAY_SIZE(lp8860_reg_defs),
 337        .cache_type = REGCACHE_NONE,
 338};
 339
 340static const struct reg_default lp8860_eeprom_defs[] = {
 341        { LP8860_EEPROM_REG_0, 0x00 },
 342        { LP8860_EEPROM_REG_1, 0x00 },
 343        { LP8860_EEPROM_REG_2, 0x00 },
 344        { LP8860_EEPROM_REG_3, 0x00 },
 345        { LP8860_EEPROM_REG_4, 0x00 },
 346        { LP8860_EEPROM_REG_5, 0x00 },
 347        { LP8860_EEPROM_REG_6, 0x00 },
 348        { LP8860_EEPROM_REG_7, 0x00 },
 349        { LP8860_EEPROM_REG_8, 0x00 },
 350        { LP8860_EEPROM_REG_9, 0x00 },
 351        { LP8860_EEPROM_REG_10, 0x00 },
 352        { LP8860_EEPROM_REG_11, 0x00 },
 353        { LP8860_EEPROM_REG_12, 0x00 },
 354        { LP8860_EEPROM_REG_13, 0x00 },
 355        { LP8860_EEPROM_REG_14, 0x00 },
 356        { LP8860_EEPROM_REG_15, 0x00 },
 357        { LP8860_EEPROM_REG_16, 0x00 },
 358        { LP8860_EEPROM_REG_17, 0x00 },
 359        { LP8860_EEPROM_REG_18, 0x00 },
 360        { LP8860_EEPROM_REG_19, 0x00 },
 361        { LP8860_EEPROM_REG_20, 0x00 },
 362        { LP8860_EEPROM_REG_21, 0x00 },
 363        { LP8860_EEPROM_REG_22, 0x00 },
 364        { LP8860_EEPROM_REG_23, 0x00 },
 365        { LP8860_EEPROM_REG_24, 0x00 },
 366};
 367
 368static const struct regmap_config lp8860_eeprom_regmap_config = {
 369        .reg_bits = 8,
 370        .val_bits = 8,
 371
 372        .max_register = LP8860_EEPROM_REG_24,
 373        .reg_defaults = lp8860_eeprom_defs,
 374        .num_reg_defaults = ARRAY_SIZE(lp8860_eeprom_defs),
 375        .cache_type = REGCACHE_NONE,
 376};
 377
 378static int lp8860_probe(struct i2c_client *client,
 379                        const struct i2c_device_id *id)
 380{
 381        int ret;
 382        struct lp8860_led *led;
 383        struct device_node *np = dev_of_node(&client->dev);
 384        struct device_node *child_node;
 385        struct led_init_data init_data = {};
 386
 387        led = devm_kzalloc(&client->dev, sizeof(*led), GFP_KERNEL);
 388        if (!led)
 389                return -ENOMEM;
 390
 391        child_node = of_get_next_available_child(np, NULL);
 392        if (!child_node)
 393                return -EINVAL;
 394
 395        led->enable_gpio = devm_gpiod_get_optional(&client->dev,
 396                                                   "enable", GPIOD_OUT_LOW);
 397        if (IS_ERR(led->enable_gpio)) {
 398                ret = PTR_ERR(led->enable_gpio);
 399                dev_err(&client->dev, "Failed to get enable gpio: %d\n", ret);
 400                return ret;
 401        }
 402
 403        led->regulator = devm_regulator_get(&client->dev, "vled");
 404        if (IS_ERR(led->regulator))
 405                led->regulator = NULL;
 406
 407        led->client = client;
 408        led->led_dev.brightness_set_blocking = lp8860_brightness_set;
 409
 410        mutex_init(&led->lock);
 411
 412        i2c_set_clientdata(client, led);
 413
 414        led->regmap = devm_regmap_init_i2c(client, &lp8860_regmap_config);
 415        if (IS_ERR(led->regmap)) {
 416                ret = PTR_ERR(led->regmap);
 417                dev_err(&client->dev, "Failed to allocate register map: %d\n",
 418                        ret);
 419                return ret;
 420        }
 421
 422        led->eeprom_regmap = devm_regmap_init_i2c(client, &lp8860_eeprom_regmap_config);
 423        if (IS_ERR(led->eeprom_regmap)) {
 424                ret = PTR_ERR(led->eeprom_regmap);
 425                dev_err(&client->dev, "Failed to allocate register map: %d\n",
 426                        ret);
 427                return ret;
 428        }
 429
 430        ret = lp8860_init(led);
 431        if (ret)
 432                return ret;
 433
 434        init_data.fwnode = of_fwnode_handle(child_node);
 435        init_data.devicename = LP8860_NAME;
 436        init_data.default_label = ":display_cluster";
 437
 438        ret = devm_led_classdev_register_ext(&client->dev, &led->led_dev,
 439                                             &init_data);
 440        if (ret) {
 441                dev_err(&client->dev, "led register err: %d\n", ret);
 442                return ret;
 443        }
 444
 445        return 0;
 446}
 447
 448static int lp8860_remove(struct i2c_client *client)
 449{
 450        struct lp8860_led *led = i2c_get_clientdata(client);
 451        int ret;
 452
 453        if (led->enable_gpio)
 454                gpiod_direction_output(led->enable_gpio, 0);
 455
 456        if (led->regulator) {
 457                ret = regulator_disable(led->regulator);
 458                if (ret)
 459                        dev_err(&led->client->dev,
 460                                "Failed to disable regulator\n");
 461        }
 462
 463        mutex_destroy(&led->lock);
 464
 465        return 0;
 466}
 467
 468static const struct i2c_device_id lp8860_id[] = {
 469        { "lp8860", 0 },
 470        { }
 471};
 472MODULE_DEVICE_TABLE(i2c, lp8860_id);
 473
 474static const struct of_device_id of_lp8860_leds_match[] = {
 475        { .compatible = "ti,lp8860", },
 476        {},
 477};
 478MODULE_DEVICE_TABLE(of, of_lp8860_leds_match);
 479
 480static struct i2c_driver lp8860_driver = {
 481        .driver = {
 482                .name   = "lp8860",
 483                .of_match_table = of_lp8860_leds_match,
 484        },
 485        .probe          = lp8860_probe,
 486        .remove         = lp8860_remove,
 487        .id_table       = lp8860_id,
 488};
 489module_i2c_driver(lp8860_driver);
 490
 491MODULE_DESCRIPTION("Texas Instruments LP8860 LED driver");
 492MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
 493MODULE_LICENSE("GPL v2");
 494