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/platform_data/leds-lm3642.h>
  19
  20#define REG_FILT_TIME                   (0x0)
  21#define REG_IVFM_MODE                   (0x1)
  22#define REG_TORCH_TIME                  (0x6)
  23#define REG_FLASH                       (0x8)
  24#define REG_I_CTRL                      (0x9)
  25#define REG_ENABLE                      (0xA)
  26#define REG_FLAG                        (0xB)
  27#define REG_MAX                         (0xB)
  28
  29#define UVLO_EN_SHIFT                   (7)
  30#define IVM_D_TH_SHIFT                  (2)
  31#define TORCH_RAMP_UP_TIME_SHIFT        (3)
  32#define TORCH_RAMP_DN_TIME_SHIFT        (0)
  33#define INDUCTOR_I_LIMIT_SHIFT          (6)
  34#define FLASH_RAMP_TIME_SHIFT           (3)
  35#define FLASH_TOUT_TIME_SHIFT           (0)
  36#define TORCH_I_SHIFT                   (4)
  37#define FLASH_I_SHIFT                   (0)
  38#define IVFM_SHIFT                      (7)
  39#define TX_PIN_EN_SHIFT                 (6)
  40#define STROBE_PIN_EN_SHIFT             (5)
  41#define TORCH_PIN_EN_SHIFT              (4)
  42#define MODE_BITS_SHIFT                 (0)
  43
  44#define UVLO_EN_MASK                    (0x1)
  45#define IVM_D_TH_MASK                   (0x7)
  46#define TORCH_RAMP_UP_TIME_MASK         (0x7)
  47#define TORCH_RAMP_DN_TIME_MASK         (0x7)
  48#define INDUCTOR_I_LIMIT_MASK           (0x1)
  49#define FLASH_RAMP_TIME_MASK            (0x7)
  50#define FLASH_TOUT_TIME_MASK            (0x7)
  51#define TORCH_I_MASK                    (0x7)
  52#define FLASH_I_MASK                    (0xF)
  53#define IVFM_MASK                       (0x1)
  54#define TX_PIN_EN_MASK                  (0x1)
  55#define STROBE_PIN_EN_MASK              (0x1)
  56#define TORCH_PIN_EN_MASK               (0x1)
  57#define MODE_BITS_MASK                  (0x73)
  58#define EX_PIN_CONTROL_MASK             (0x71)
  59#define EX_PIN_ENABLE_MASK              (0x70)
  60
  61enum lm3642_mode {
  62        MODES_STASNDBY = 0,
  63        MODES_INDIC,
  64        MODES_TORCH,
  65        MODES_FLASH
  66};
  67
  68struct lm3642_chip_data {
  69        struct device *dev;
  70
  71        struct led_classdev cdev_flash;
  72        struct led_classdev cdev_torch;
  73        struct led_classdev cdev_indicator;
  74
  75        u8 br_flash;
  76        u8 br_torch;
  77        u8 br_indicator;
  78
  79        enum lm3642_torch_pin_enable torch_pin;
  80        enum lm3642_strobe_pin_enable strobe_pin;
  81        enum lm3642_tx_pin_enable tx_pin;
  82
  83        struct lm3642_platform_data *pdata;
  84        struct regmap *regmap;
  85        struct mutex lock;
  86
  87        unsigned int last_flag;
  88};
  89
  90/* chip initialize */
  91static int lm3642_chip_init(struct lm3642_chip_data *chip)
  92{
  93        int ret;
  94        struct lm3642_platform_data *pdata = chip->pdata;
  95
  96        /* set enable register */
  97        ret = regmap_update_bits(chip->regmap, REG_ENABLE, EX_PIN_ENABLE_MASK,
  98                                 pdata->tx_pin);
  99        if (ret < 0)
 100                dev_err(chip->dev, "Failed to update REG_ENABLE Register\n");
 101        return ret;
 102}
 103
 104/* chip control */
 105static int lm3642_control(struct lm3642_chip_data *chip,
 106                          u8 brightness, enum lm3642_mode opmode)
 107{
 108        int ret;
 109
 110        ret = regmap_read(chip->regmap, REG_FLAG, &chip->last_flag);
 111        if (ret < 0) {
 112                dev_err(chip->dev, "Failed to read REG_FLAG Register\n");
 113                goto out;
 114        }
 115
 116        if (chip->last_flag)
 117                dev_info(chip->dev, "Last FLAG is 0x%x\n", chip->last_flag);
 118
 119        /* brightness 0 means off-state */
 120        if (!brightness)
 121                opmode = MODES_STASNDBY;
 122
 123        switch (opmode) {
 124        case MODES_TORCH:
 125                ret = regmap_update_bits(chip->regmap, REG_I_CTRL,
 126                                         TORCH_I_MASK << TORCH_I_SHIFT,
 127                                         (brightness - 1) << TORCH_I_SHIFT);
 128
 129                if (chip->torch_pin)
 130                        opmode |= (TORCH_PIN_EN_MASK << TORCH_PIN_EN_SHIFT);
 131                break;
 132
 133        case MODES_FLASH:
 134                ret = regmap_update_bits(chip->regmap, REG_I_CTRL,
 135                                         FLASH_I_MASK << FLASH_I_SHIFT,
 136                                         (brightness - 1) << FLASH_I_SHIFT);
 137
 138                if (chip->strobe_pin)
 139                        opmode |= (STROBE_PIN_EN_MASK << STROBE_PIN_EN_SHIFT);
 140                break;
 141
 142        case MODES_INDIC:
 143                ret = regmap_update_bits(chip->regmap, REG_I_CTRL,
 144                                         TORCH_I_MASK << TORCH_I_SHIFT,
 145                                         (brightness - 1) << TORCH_I_SHIFT);
 146                break;
 147
 148        case MODES_STASNDBY:
 149
 150                break;
 151
 152        default:
 153                return ret;
 154        }
 155        if (ret < 0) {
 156                dev_err(chip->dev, "Failed to write REG_I_CTRL Register\n");
 157                goto out;
 158        }
 159
 160        if (chip->tx_pin)
 161                opmode |= (TX_PIN_EN_MASK << TX_PIN_EN_SHIFT);
 162
 163        ret = regmap_update_bits(chip->regmap, REG_ENABLE,
 164                                 MODE_BITS_MASK << MODE_BITS_SHIFT,
 165                                 opmode << MODE_BITS_SHIFT);
 166out:
 167        return ret;
 168}
 169
 170/* torch */
 171
 172/* torch pin config for lm3642*/
 173static ssize_t lm3642_torch_pin_store(struct device *dev,
 174                                      struct device_attribute *attr,
 175                                      const char *buf, size_t size)
 176{
 177        ssize_t ret;
 178        struct led_classdev *led_cdev = dev_get_drvdata(dev);
 179        struct lm3642_chip_data *chip =
 180            container_of(led_cdev, struct lm3642_chip_data, cdev_indicator);
 181        unsigned int state;
 182
 183        ret = kstrtouint(buf, 10, &state);
 184        if (ret)
 185                goto out_strtoint;
 186        if (state != 0)
 187                state = 0x01 << TORCH_PIN_EN_SHIFT;
 188
 189        chip->torch_pin = state;
 190        ret = regmap_update_bits(chip->regmap, REG_ENABLE,
 191                                 TORCH_PIN_EN_MASK << TORCH_PIN_EN_SHIFT,
 192                                 state);
 193        if (ret < 0)
 194                goto out;
 195
 196        return size;
 197out:
 198        dev_err(chip->dev, "%s:i2c access fail to register\n", __func__);
 199        return ret;
 200out_strtoint:
 201        dev_err(chip->dev, "%s: fail to change str to int\n", __func__);
 202        return ret;
 203}
 204
 205static DEVICE_ATTR(torch_pin, S_IWUSR, NULL, lm3642_torch_pin_store);
 206
 207static int lm3642_torch_brightness_set(struct led_classdev *cdev,
 208                                        enum led_brightness brightness)
 209{
 210        struct lm3642_chip_data *chip =
 211            container_of(cdev, struct lm3642_chip_data, cdev_torch);
 212        int ret;
 213
 214        mutex_lock(&chip->lock);
 215        chip->br_torch = brightness;
 216        ret = lm3642_control(chip, chip->br_torch, MODES_TORCH);
 217        mutex_unlock(&chip->lock);
 218        return ret;
 219}
 220
 221/* flash */
 222
 223/* strobe pin config for lm3642*/
 224static ssize_t lm3642_strobe_pin_store(struct device *dev,
 225                                       struct device_attribute *attr,
 226                                       const char *buf, size_t size)
 227{
 228        ssize_t ret;
 229        struct led_classdev *led_cdev = dev_get_drvdata(dev);
 230        struct lm3642_chip_data *chip =
 231            container_of(led_cdev, struct lm3642_chip_data, cdev_indicator);
 232        unsigned int state;
 233
 234        ret = kstrtouint(buf, 10, &state);
 235        if (ret)
 236                goto out_strtoint;
 237        if (state != 0)
 238                state = 0x01 << STROBE_PIN_EN_SHIFT;
 239
 240        chip->strobe_pin = state;
 241        ret = regmap_update_bits(chip->regmap, REG_ENABLE,
 242                                 STROBE_PIN_EN_MASK << STROBE_PIN_EN_SHIFT,
 243                                 state);
 244        if (ret < 0)
 245                goto out;
 246
 247        return size;
 248out:
 249        dev_err(chip->dev, "%s:i2c access fail to register\n", __func__);
 250        return ret;
 251out_strtoint:
 252        dev_err(chip->dev, "%s: fail to change str to int\n", __func__);
 253        return ret;
 254}
 255
 256static DEVICE_ATTR(strobe_pin, S_IWUSR, NULL, lm3642_strobe_pin_store);
 257
 258static int lm3642_strobe_brightness_set(struct led_classdev *cdev,
 259                                         enum led_brightness brightness)
 260{
 261        struct lm3642_chip_data *chip =
 262            container_of(cdev, struct lm3642_chip_data, cdev_flash);
 263        int ret;
 264
 265        mutex_lock(&chip->lock);
 266        chip->br_flash = brightness;
 267        ret = lm3642_control(chip, chip->br_flash, MODES_FLASH);
 268        mutex_unlock(&chip->lock);
 269        return ret;
 270}
 271
 272/* indicator */
 273static int lm3642_indicator_brightness_set(struct led_classdev *cdev,
 274                                            enum led_brightness brightness)
 275{
 276        struct lm3642_chip_data *chip =
 277            container_of(cdev, struct lm3642_chip_data, cdev_indicator);
 278        int ret;
 279
 280        mutex_lock(&chip->lock);
 281        chip->br_indicator = brightness;
 282        ret = lm3642_control(chip, chip->br_indicator, MODES_INDIC);
 283        mutex_unlock(&chip->lock);
 284        return ret;
 285}
 286
 287static const struct regmap_config lm3642_regmap = {
 288        .reg_bits = 8,
 289        .val_bits = 8,
 290        .max_register = REG_MAX,
 291};
 292
 293static struct attribute *lm3642_flash_attrs[] = {
 294        &dev_attr_strobe_pin.attr,
 295        NULL
 296};
 297ATTRIBUTE_GROUPS(lm3642_flash);
 298
 299static struct attribute *lm3642_torch_attrs[] = {
 300        &dev_attr_torch_pin.attr,
 301        NULL
 302};
 303ATTRIBUTE_GROUPS(lm3642_torch);
 304
 305static int lm3642_probe(struct i2c_client *client,
 306                                  const struct i2c_device_id *id)
 307{
 308        struct lm3642_platform_data *pdata = dev_get_platdata(&client->dev);
 309        struct lm3642_chip_data *chip;
 310
 311        int err;
 312
 313        if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
 314                dev_err(&client->dev, "i2c functionality check fail.\n");
 315                return -EOPNOTSUPP;
 316        }
 317
 318        if (pdata == NULL) {
 319                dev_err(&client->dev, "needs Platform Data.\n");
 320                return -ENODATA;
 321        }
 322
 323        chip = devm_kzalloc(&client->dev,
 324                            sizeof(struct lm3642_chip_data), GFP_KERNEL);
 325        if (!chip)
 326                return -ENOMEM;
 327
 328        chip->dev = &client->dev;
 329        chip->pdata = pdata;
 330
 331        chip->tx_pin = pdata->tx_pin;
 332        chip->torch_pin = pdata->torch_pin;
 333        chip->strobe_pin = pdata->strobe_pin;
 334
 335        chip->regmap = devm_regmap_init_i2c(client, &lm3642_regmap);
 336        if (IS_ERR(chip->regmap)) {
 337                err = PTR_ERR(chip->regmap);
 338                dev_err(&client->dev, "Failed to allocate register map: %d\n",
 339                        err);
 340                return err;
 341        }
 342
 343        mutex_init(&chip->lock);
 344        i2c_set_clientdata(client, chip);
 345
 346        err = lm3642_chip_init(chip);
 347        if (err < 0)
 348                goto err_out;
 349
 350        /* flash */
 351        chip->cdev_flash.name = "flash";
 352        chip->cdev_flash.max_brightness = 16;
 353        chip->cdev_flash.brightness_set_blocking = lm3642_strobe_brightness_set;
 354        chip->cdev_flash.default_trigger = "flash";
 355        chip->cdev_flash.groups = lm3642_flash_groups,
 356        err = led_classdev_register((struct device *)
 357                                    &client->dev, &chip->cdev_flash);
 358        if (err < 0) {
 359                dev_err(chip->dev, "failed to register flash\n");
 360                goto err_out;
 361        }
 362
 363        /* torch */
 364        chip->cdev_torch.name = "torch";
 365        chip->cdev_torch.max_brightness = 8;
 366        chip->cdev_torch.brightness_set_blocking = lm3642_torch_brightness_set;
 367        chip->cdev_torch.default_trigger = "torch";
 368        chip->cdev_torch.groups = lm3642_torch_groups,
 369        err = led_classdev_register((struct device *)
 370                                    &client->dev, &chip->cdev_torch);
 371        if (err < 0) {
 372                dev_err(chip->dev, "failed to register torch\n");
 373                goto err_create_torch_file;
 374        }
 375
 376        /* indicator */
 377        chip->cdev_indicator.name = "indicator";
 378        chip->cdev_indicator.max_brightness = 8;
 379        chip->cdev_indicator.brightness_set_blocking =
 380                                                lm3642_indicator_brightness_set;
 381        err = led_classdev_register((struct device *)
 382                                    &client->dev, &chip->cdev_indicator);
 383        if (err < 0) {
 384                dev_err(chip->dev, "failed to register indicator\n");
 385                goto err_create_indicator_file;
 386        }
 387
 388        dev_info(&client->dev, "LM3642 is initialized\n");
 389        return 0;
 390
 391err_create_indicator_file:
 392        led_classdev_unregister(&chip->cdev_torch);
 393err_create_torch_file:
 394        led_classdev_unregister(&chip->cdev_flash);
 395err_out:
 396        return err;
 397}
 398
 399static int lm3642_remove(struct i2c_client *client)
 400{
 401        struct lm3642_chip_data *chip = i2c_get_clientdata(client);
 402
 403        led_classdev_unregister(&chip->cdev_indicator);
 404        led_classdev_unregister(&chip->cdev_torch);
 405        led_classdev_unregister(&chip->cdev_flash);
 406        regmap_write(chip->regmap, REG_ENABLE, 0);
 407        return 0;
 408}
 409
 410static const struct i2c_device_id lm3642_id[] = {
 411        {LM3642_NAME, 0},
 412        {}
 413};
 414
 415MODULE_DEVICE_TABLE(i2c, lm3642_id);
 416
 417static struct i2c_driver lm3642_i2c_driver = {
 418        .driver = {
 419                   .name = LM3642_NAME,
 420                   .pm = NULL,
 421                   },
 422        .probe = lm3642_probe,
 423        .remove = lm3642_remove,
 424        .id_table = lm3642_id,
 425};
 426
 427module_i2c_driver(lm3642_i2c_driver);
 428
 429MODULE_DESCRIPTION("Texas Instruments Flash Lighting driver for LM3642");
 430MODULE_AUTHOR("Daniel Jeong <daniel.jeong@ti.com>");
 431MODULE_AUTHOR("G.Shark Jeong <gshark.jeong@gmail.com>");
 432MODULE_LICENSE("GPL v2");
 433