linux/drivers/leds/leds-lm3642.c
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   1/*
   2* Simple driver for Texas Instruments LM3642 LED Flash driver chip
   3* Copyright (C) 2012 Texas Instruments
   4*
   5* This program is free software; you can redistribute it and/or modify
   6* it under the terms of the GNU General Public License version 2 as
   7* published by the Free Software Foundation.
   8*
   9*/
  10#include <linux/module.h>
  11#include <linux/delay.h>
  12#include <linux/i2c.h>
  13#include <linux/leds.h>
  14#include <linux/slab.h>
  15#include <linux/platform_device.h>
  16#include <linux/fs.h>
  17#include <linux/regmap.h>
  18#include <linux/workqueue.h>
  19#include <linux/platform_data/leds-lm3642.h>
  20
  21#define REG_FILT_TIME                   (0x0)
  22#define REG_IVFM_MODE                   (0x1)
  23#define REG_TORCH_TIME                  (0x6)
  24#define REG_FLASH                       (0x8)
  25#define REG_I_CTRL                      (0x9)
  26#define REG_ENABLE                      (0xA)
  27#define REG_FLAG                        (0xB)
  28#define REG_MAX                         (0xB)
  29
  30#define UVLO_EN_SHIFT                   (7)
  31#define IVM_D_TH_SHIFT                  (2)
  32#define TORCH_RAMP_UP_TIME_SHIFT        (3)
  33#define TORCH_RAMP_DN_TIME_SHIFT        (0)
  34#define INDUCTOR_I_LIMIT_SHIFT          (6)
  35#define FLASH_RAMP_TIME_SHIFT           (3)
  36#define FLASH_TOUT_TIME_SHIFT           (0)
  37#define TORCH_I_SHIFT                   (4)
  38#define FLASH_I_SHIFT                   (0)
  39#define IVFM_SHIFT                      (7)
  40#define TX_PIN_EN_SHIFT                 (6)
  41#define STROBE_PIN_EN_SHIFT             (5)
  42#define TORCH_PIN_EN_SHIFT              (4)
  43#define MODE_BITS_SHIFT                 (0)
  44
  45#define UVLO_EN_MASK                    (0x1)
  46#define IVM_D_TH_MASK                   (0x7)
  47#define TORCH_RAMP_UP_TIME_MASK         (0x7)
  48#define TORCH_RAMP_DN_TIME_MASK         (0x7)
  49#define INDUCTOR_I_LIMIT_MASK           (0x1)
  50#define FLASH_RAMP_TIME_MASK            (0x7)
  51#define FLASH_TOUT_TIME_MASK            (0x7)
  52#define TORCH_I_MASK                    (0x7)
  53#define FLASH_I_MASK                    (0xF)
  54#define IVFM_MASK                       (0x1)
  55#define TX_PIN_EN_MASK                  (0x1)
  56#define STROBE_PIN_EN_MASK              (0x1)
  57#define TORCH_PIN_EN_MASK               (0x1)
  58#define MODE_BITS_MASK                  (0x73)
  59#define EX_PIN_CONTROL_MASK             (0x71)
  60#define EX_PIN_ENABLE_MASK              (0x70)
  61
  62enum lm3642_mode {
  63        MODES_STASNDBY = 0,
  64        MODES_INDIC,
  65        MODES_TORCH,
  66        MODES_FLASH
  67};
  68
  69struct lm3642_chip_data {
  70        struct device *dev;
  71
  72        struct led_classdev cdev_flash;
  73        struct led_classdev cdev_torch;
  74        struct led_classdev cdev_indicator;
  75
  76        struct work_struct work_flash;
  77        struct work_struct work_torch;
  78        struct work_struct work_indicator;
  79
  80        u8 br_flash;
  81        u8 br_torch;
  82        u8 br_indicator;
  83
  84        enum lm3642_torch_pin_enable torch_pin;
  85        enum lm3642_strobe_pin_enable strobe_pin;
  86        enum lm3642_tx_pin_enable tx_pin;
  87
  88        struct lm3642_platform_data *pdata;
  89        struct regmap *regmap;
  90        struct mutex lock;
  91
  92        unsigned int last_flag;
  93};
  94
  95/* chip initialize */
  96static int __devinit lm3642_chip_init(struct lm3642_chip_data *chip)
  97{
  98        int ret;
  99        struct lm3642_platform_data *pdata = chip->pdata;
 100
 101        /* set enable register */
 102        ret = regmap_update_bits(chip->regmap, REG_ENABLE, EX_PIN_ENABLE_MASK,
 103                                 pdata->tx_pin);
 104        if (ret < 0)
 105                dev_err(chip->dev, "Failed to update REG_ENABLE Register\n");
 106        return ret;
 107}
 108
 109/* chip control */
 110static int lm3642_control(struct lm3642_chip_data *chip,
 111                          u8 brightness, enum lm3642_mode opmode)
 112{
 113        int ret;
 114
 115        ret = regmap_read(chip->regmap, REG_FLAG, &chip->last_flag);
 116        if (ret < 0) {
 117                dev_err(chip->dev, "Failed to read REG_FLAG Register\n");
 118                goto out;
 119        }
 120
 121        if (chip->last_flag)
 122                dev_info(chip->dev, "Last FLAG is 0x%x\n", chip->last_flag);
 123
 124        /* brightness 0 means off-state */
 125        if (!brightness)
 126                opmode = MODES_STASNDBY;
 127
 128        switch (opmode) {
 129        case MODES_TORCH:
 130                ret = regmap_update_bits(chip->regmap, REG_I_CTRL,
 131                                         TORCH_I_MASK << TORCH_I_SHIFT,
 132                                         (brightness - 1) << TORCH_I_SHIFT);
 133
 134                if (chip->torch_pin)
 135                        opmode |= (TORCH_PIN_EN_MASK << TORCH_PIN_EN_SHIFT);
 136                break;
 137
 138        case MODES_FLASH:
 139                ret = regmap_update_bits(chip->regmap, REG_I_CTRL,
 140                                         FLASH_I_MASK << FLASH_I_SHIFT,
 141                                         (brightness - 1) << FLASH_I_SHIFT);
 142
 143                if (chip->strobe_pin)
 144                        opmode |= (STROBE_PIN_EN_MASK << STROBE_PIN_EN_SHIFT);
 145                break;
 146
 147        case MODES_INDIC:
 148                ret = regmap_update_bits(chip->regmap, REG_I_CTRL,
 149                                         TORCH_I_MASK << TORCH_I_SHIFT,
 150                                         (brightness - 1) << TORCH_I_SHIFT);
 151                break;
 152
 153        case MODES_STASNDBY:
 154
 155                break;
 156
 157        default:
 158                return ret;
 159        }
 160        if (ret < 0) {
 161                dev_err(chip->dev, "Failed to write REG_I_CTRL Register\n");
 162                goto out;
 163        }
 164
 165        if (chip->tx_pin)
 166                opmode |= (TX_PIN_EN_MASK << TX_PIN_EN_SHIFT);
 167
 168        ret = regmap_update_bits(chip->regmap, REG_ENABLE,
 169                                 MODE_BITS_MASK << MODE_BITS_SHIFT,
 170                                 opmode << MODE_BITS_SHIFT);
 171out:
 172        return ret;
 173}
 174
 175/* torch */
 176
 177/* torch pin config for lm3642*/
 178static ssize_t lm3642_torch_pin_store(struct device *dev,
 179                                      struct device_attribute *devAttr,
 180                                      const char *buf, size_t size)
 181{
 182        ssize_t ret;
 183        struct led_classdev *led_cdev = dev_get_drvdata(dev);
 184        struct lm3642_chip_data *chip =
 185            container_of(led_cdev, struct lm3642_chip_data, cdev_indicator);
 186        unsigned int state;
 187
 188        ret = kstrtouint(buf, 10, &state);
 189        if (ret)
 190                goto out_strtoint;
 191        if (state != 0)
 192                state = 0x01 << TORCH_PIN_EN_SHIFT;
 193
 194        chip->torch_pin = state;
 195        ret = regmap_update_bits(chip->regmap, REG_ENABLE,
 196                                 TORCH_PIN_EN_MASK << TORCH_PIN_EN_SHIFT,
 197                                 state);
 198        if (ret < 0)
 199                goto out;
 200
 201        return size;
 202out:
 203        dev_err(chip->dev, "%s:i2c access fail to register\n", __func__);
 204        return size;
 205out_strtoint:
 206        dev_err(chip->dev, "%s: fail to change str to int\n", __func__);
 207        return size;
 208}
 209
 210static DEVICE_ATTR(torch_pin, 0666, NULL, lm3642_torch_pin_store);
 211
 212static void lm3642_deferred_torch_brightness_set(struct work_struct *work)
 213{
 214        struct lm3642_chip_data *chip =
 215            container_of(work, struct lm3642_chip_data, work_torch);
 216
 217        mutex_lock(&chip->lock);
 218        lm3642_control(chip, chip->br_torch, MODES_TORCH);
 219        mutex_unlock(&chip->lock);
 220}
 221
 222static void lm3642_torch_brightness_set(struct led_classdev *cdev,
 223                                        enum led_brightness brightness)
 224{
 225        struct lm3642_chip_data *chip =
 226            container_of(cdev, struct lm3642_chip_data, cdev_torch);
 227
 228        chip->br_torch = brightness;
 229        schedule_work(&chip->work_torch);
 230}
 231
 232/* flash */
 233
 234/* strobe pin config for lm3642*/
 235static ssize_t lm3642_strobe_pin_store(struct device *dev,
 236                                       struct device_attribute *devAttr,
 237                                       const char *buf, size_t size)
 238{
 239        ssize_t ret;
 240        struct led_classdev *led_cdev = dev_get_drvdata(dev);
 241        struct lm3642_chip_data *chip =
 242            container_of(led_cdev, struct lm3642_chip_data, cdev_indicator);
 243        unsigned int state;
 244
 245        ret = kstrtouint(buf, 10, &state);
 246        if (ret)
 247                goto out_strtoint;
 248        if (state != 0)
 249                state = 0x01 << STROBE_PIN_EN_SHIFT;
 250
 251        chip->strobe_pin = state;
 252        ret = regmap_update_bits(chip->regmap, REG_ENABLE,
 253                                 STROBE_PIN_EN_MASK << STROBE_PIN_EN_SHIFT,
 254                                 state);
 255        if (ret < 0)
 256                goto out;
 257
 258        return size;
 259out:
 260        dev_err(chip->dev, "%s:i2c access fail to register\n", __func__);
 261        return size;
 262out_strtoint:
 263        dev_err(chip->dev, "%s: fail to change str to int\n", __func__);
 264        return size;
 265}
 266
 267static DEVICE_ATTR(strobe_pin, 0666, NULL, lm3642_strobe_pin_store);
 268
 269static void lm3642_deferred_strobe_brightness_set(struct work_struct *work)
 270{
 271        struct lm3642_chip_data *chip =
 272            container_of(work, struct lm3642_chip_data, work_flash);
 273
 274        mutex_lock(&chip->lock);
 275        lm3642_control(chip, chip->br_flash, MODES_FLASH);
 276        mutex_unlock(&chip->lock);
 277}
 278
 279static void lm3642_strobe_brightness_set(struct led_classdev *cdev,
 280                                         enum led_brightness brightness)
 281{
 282        struct lm3642_chip_data *chip =
 283            container_of(cdev, struct lm3642_chip_data, cdev_flash);
 284
 285        chip->br_flash = brightness;
 286        schedule_work(&chip->work_flash);
 287}
 288
 289/* indicator */
 290static void lm3642_deferred_indicator_brightness_set(struct work_struct *work)
 291{
 292        struct lm3642_chip_data *chip =
 293            container_of(work, struct lm3642_chip_data, work_indicator);
 294
 295        mutex_lock(&chip->lock);
 296        lm3642_control(chip, chip->br_indicator, MODES_INDIC);
 297        mutex_unlock(&chip->lock);
 298}
 299
 300static void lm3642_indicator_brightness_set(struct led_classdev *cdev,
 301                                            enum led_brightness brightness)
 302{
 303        struct lm3642_chip_data *chip =
 304            container_of(cdev, struct lm3642_chip_data, cdev_indicator);
 305
 306        chip->br_indicator = brightness;
 307        schedule_work(&chip->work_indicator);
 308}
 309
 310static const struct regmap_config lm3642_regmap = {
 311        .reg_bits = 8,
 312        .val_bits = 8,
 313        .max_register = REG_MAX,
 314};
 315
 316static int __devinit lm3642_probe(struct i2c_client *client,
 317                                  const struct i2c_device_id *id)
 318{
 319        struct lm3642_platform_data *pdata = client->dev.platform_data;
 320        struct lm3642_chip_data *chip;
 321
 322        int err;
 323
 324        if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
 325                dev_err(&client->dev, "i2c functionality check fail.\n");
 326                return -EOPNOTSUPP;
 327        }
 328
 329        if (pdata == NULL) {
 330                dev_err(&client->dev, "needs Platform Data.\n");
 331                return -ENODATA;
 332        }
 333
 334        chip = devm_kzalloc(&client->dev,
 335                            sizeof(struct lm3642_chip_data), GFP_KERNEL);
 336        if (!chip)
 337                return -ENOMEM;
 338
 339        chip->dev = &client->dev;
 340        chip->pdata = pdata;
 341
 342        chip->tx_pin = pdata->tx_pin;
 343        chip->torch_pin = pdata->torch_pin;
 344        chip->strobe_pin = pdata->strobe_pin;
 345
 346        chip->regmap = devm_regmap_init_i2c(client, &lm3642_regmap);
 347        if (IS_ERR(chip->regmap)) {
 348                err = PTR_ERR(chip->regmap);
 349                dev_err(&client->dev, "Failed to allocate register map: %d\n",
 350                        err);
 351                return err;
 352        }
 353
 354        mutex_init(&chip->lock);
 355        i2c_set_clientdata(client, chip);
 356
 357        err = lm3642_chip_init(chip);
 358        if (err < 0)
 359                goto err_out;
 360
 361        /* flash */
 362        INIT_WORK(&chip->work_flash, lm3642_deferred_strobe_brightness_set);
 363        chip->cdev_flash.name = "flash";
 364        chip->cdev_flash.max_brightness = 16;
 365        chip->cdev_flash.brightness_set = lm3642_strobe_brightness_set;
 366        err = led_classdev_register((struct device *)
 367                                    &client->dev, &chip->cdev_flash);
 368        if (err < 0) {
 369                dev_err(chip->dev, "failed to register flash\n");
 370                goto err_out;
 371        }
 372        err = device_create_file(chip->cdev_flash.dev, &dev_attr_strobe_pin);
 373        if (err < 0) {
 374                dev_err(chip->dev, "failed to create strobe-pin file\n");
 375                goto err_create_flash_pin_file;
 376        }
 377
 378        /* torch */
 379        INIT_WORK(&chip->work_torch, lm3642_deferred_torch_brightness_set);
 380        chip->cdev_torch.name = "torch";
 381        chip->cdev_torch.max_brightness = 8;
 382        chip->cdev_torch.brightness_set = lm3642_torch_brightness_set;
 383        err = led_classdev_register((struct device *)
 384                                    &client->dev, &chip->cdev_torch);
 385        if (err < 0) {
 386                dev_err(chip->dev, "failed to register torch\n");
 387                goto err_create_torch_file;
 388        }
 389        err = device_create_file(chip->cdev_torch.dev, &dev_attr_torch_pin);
 390        if (err < 0) {
 391                dev_err(chip->dev, "failed to create torch-pin file\n");
 392                goto err_create_torch_pin_file;
 393        }
 394
 395        /* indicator */
 396        INIT_WORK(&chip->work_indicator,
 397                  lm3642_deferred_indicator_brightness_set);
 398        chip->cdev_indicator.name = "indicator";
 399        chip->cdev_indicator.max_brightness = 8;
 400        chip->cdev_indicator.brightness_set = lm3642_indicator_brightness_set;
 401        err = led_classdev_register((struct device *)
 402                                    &client->dev, &chip->cdev_indicator);
 403        if (err < 0) {
 404                dev_err(chip->dev, "failed to register indicator\n");
 405                goto err_create_indicator_file;
 406        }
 407
 408        dev_info(&client->dev, "LM3642 is initialized\n");
 409        return 0;
 410
 411err_create_indicator_file:
 412        device_remove_file(chip->cdev_torch.dev, &dev_attr_torch_pin);
 413err_create_torch_pin_file:
 414        led_classdev_unregister(&chip->cdev_torch);
 415err_create_torch_file:
 416        device_remove_file(chip->cdev_flash.dev, &dev_attr_strobe_pin);
 417err_create_flash_pin_file:
 418        led_classdev_unregister(&chip->cdev_flash);
 419err_out:
 420        return err;
 421}
 422
 423static int __devexit lm3642_remove(struct i2c_client *client)
 424{
 425        struct lm3642_chip_data *chip = i2c_get_clientdata(client);
 426
 427        led_classdev_unregister(&chip->cdev_indicator);
 428        flush_work(&chip->work_indicator);
 429        device_remove_file(chip->cdev_torch.dev, &dev_attr_torch_pin);
 430        led_classdev_unregister(&chip->cdev_torch);
 431        flush_work(&chip->work_torch);
 432        device_remove_file(chip->cdev_flash.dev, &dev_attr_strobe_pin);
 433        led_classdev_unregister(&chip->cdev_flash);
 434        flush_work(&chip->work_flash);
 435        regmap_write(chip->regmap, REG_ENABLE, 0);
 436        return 0;
 437}
 438
 439static const struct i2c_device_id lm3642_id[] = {
 440        {LM3642_NAME, 0},
 441        {}
 442};
 443
 444MODULE_DEVICE_TABLE(i2c, lm3642_id);
 445
 446static struct i2c_driver lm3642_i2c_driver = {
 447        .driver = {
 448                   .name = LM3642_NAME,
 449                   .owner = THIS_MODULE,
 450                   .pm = NULL,
 451                   },
 452        .probe = lm3642_probe,
 453        .remove = __devexit_p(lm3642_remove),
 454        .id_table = lm3642_id,
 455};
 456
 457module_i2c_driver(lm3642_i2c_driver);
 458
 459MODULE_DESCRIPTION("Texas Instruments Flash Lighting driver for LM3642");
 460MODULE_AUTHOR("Daniel Jeong <daniel.jeong@ti.com>");
 461MODULE_AUTHOR("G.Shark Jeong <gshark.jeong@gmail.com>");
 462MODULE_LICENSE("GPL v2");
 463
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