drivers/leds/leds-lm3642.c

   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
  62 enum lm3642_mode {
  63         MODES_STASNDBY = 0,
  64         MODES_INDIC,
  65         MODES_TORCH,
  66         MODES_FLASH
  67 };
  68
  69 struct 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 */
  96 static int 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 */
 110 static 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);
 171 out:
 172         return ret;
 173 }
 174
 175 /* torch */
 176
 177 /* torch pin config for lm3642*/
 178 static ssize_t lm3642_torch_pin_store(struct device *dev,
 179                                       struct device_attribute *attr,
 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;
 202 out:
 203         dev_err(chip->dev, "%s:i2c access fail to register\n", __func__);
 204         return ret;
 205 out_strtoint:
 206         dev_err(chip->dev, "%s: fail to change str to int\n", __func__);
 207         return ret;
 208 }
 209
 210 static DEVICE_ATTR(torch_pin, S_IWUSR, NULL, lm3642_torch_pin_store);
 211
 212 static 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
 222 static 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*/
 235 static ssize_t lm3642_strobe_pin_store(struct device *dev,
 236                                        struct device_attribute *attr,
 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;
 259 out:
 260         dev_err(chip->dev, "%s:i2c access fail to register\n", __func__);
 261         return ret;
 262 out_strtoint:
 263         dev_err(chip->dev, "%s: fail to change str to int\n", __func__);
 264         return ret;
 265 }
 266
 267 static DEVICE_ATTR(strobe_pin, S_IWUSR, NULL, lm3642_strobe_pin_store);
 268
 269 static 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
 279 static 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 */
 290 static 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
 300 static 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
 310 static const struct regmap_config lm3642_regmap = {
 311         .reg_bits = 8,
 312         .val_bits = 8,
 313         .max_register = REG_MAX,
 314 };
 315
 316 static struct attribute *lm3642_flash_attrs[] = {
 317         &dev_attr_strobe_pin.attr,
 318         NULL
 319 };
 320 ATTRIBUTE_GROUPS(lm3642_flash);
 321
 322 static struct attribute *lm3642_torch_attrs[] = {
 323         &dev_attr_torch_pin.attr,
 324         NULL
 325 };
 326 ATTRIBUTE_GROUPS(lm3642_torch);
 327
 328 static int lm3642_probe(struct i2c_client *client,
 329                                   const struct i2c_device_id *id)
 330 {
 331         struct lm3642_platform_data *pdata = dev_get_platdata(&client->dev);
 332         struct lm3642_chip_data *chip;
 333
 334         int err;
 335
 336         if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
 337                 dev_err(&client->dev, "i2c functionality check fail.\n");
 338                 return -EOPNOTSUPP;
 339         }
 340
 341         if (pdata == NULL) {
 342                 dev_err(&client->dev, "needs Platform Data.\n");
 343                 return -ENODATA;
 344         }
 345
 346         chip = devm_kzalloc(&client->dev,
 347                             sizeof(struct lm3642_chip_data), GFP_KERNEL);
 348         if (!chip)
 349                 return -ENOMEM;
 350
 351         chip->dev = &client->dev;
 352         chip->pdata = pdata;
 353
 354         chip->tx_pin = pdata->tx_pin;
 355         chip->torch_pin = pdata->torch_pin;
 356         chip->strobe_pin = pdata->strobe_pin;
 357
 358         chip->regmap = devm_regmap_init_i2c(client, &lm3642_regmap);
 359         if (IS_ERR(chip->regmap)) {
 360                 err = PTR_ERR(chip->regmap);
 361                 dev_err(&client->dev, "Failed to allocate register map: %d\n",
 362                         err);
 363                 return err;
 364         }
 365
 366         mutex_init(&chip->lock);
 367         i2c_set_clientdata(client, chip);
 368
 369         err = lm3642_chip_init(chip);
 370         if (err < 0)
 371                 goto err_out;
 372
 373         /* flash */
 374         INIT_WORK(&chip->work_flash, lm3642_deferred_strobe_brightness_set);
 375         chip->cdev_flash.name = "flash";
 376         chip->cdev_flash.max_brightness = 16;
 377         chip->cdev_flash.brightness_set = lm3642_strobe_brightness_set;
 378         chip->cdev_flash.default_trigger = "flash";
 379         chip->cdev_flash.groups = lm3642_flash_groups,
 380         err = led_classdev_register((struct device *)
 381                                     &client->dev, &chip->cdev_flash);
 382         if (err < 0) {
 383                 dev_err(chip->dev, "failed to register flash\n");
 384                 goto err_out;
 385         }
 386
 387         /* torch */
 388         INIT_WORK(&chip->work_torch, lm3642_deferred_torch_brightness_set);
 389         chip->cdev_torch.name = "torch";
 390         chip->cdev_torch.max_brightness = 8;
 391         chip->cdev_torch.brightness_set = lm3642_torch_brightness_set;
 392         chip->cdev_torch.default_trigger = "torch";
 393         chip->cdev_torch.groups = lm3642_torch_groups,
 394         err = led_classdev_register((struct device *)
 395                                     &client->dev, &chip->cdev_torch);
 396         if (err < 0) {
 397                 dev_err(chip->dev, "failed to register torch\n");
 398                 goto err_create_torch_file;
 399         }
 400
 401         /* indicator */
 402         INIT_WORK(&chip->work_indicator,
 403                   lm3642_deferred_indicator_brightness_set);
 404         chip->cdev_indicator.name = "indicator";
 405         chip->cdev_indicator.max_brightness = 8;
 406         chip->cdev_indicator.brightness_set = lm3642_indicator_brightness_set;
 407         err = led_classdev_register((struct device *)
 408                                     &client->dev, &chip->cdev_indicator);
 409         if (err < 0) {
 410                 dev_err(chip->dev, "failed to register indicator\n");
 411                 goto err_create_indicator_file;
 412         }
 413
 414         dev_info(&client->dev, "LM3642 is initialized\n");
 415         return 0;
 416
 417 err_create_indicator_file:
 418         led_classdev_unregister(&chip->cdev_torch);
 419 err_create_torch_file:
 420         led_classdev_unregister(&chip->cdev_flash);
 421 err_out:
 422         return err;
 423 }
 424
 425 static int lm3642_remove(struct i2c_client *client)
 426 {
 427         struct lm3642_chip_data *chip = i2c_get_clientdata(client);
 428
 429         led_classdev_unregister(&chip->cdev_indicator);
 430         flush_work(&chip->work_indicator);
 431         led_classdev_unregister(&chip->cdev_torch);
 432         flush_work(&chip->work_torch);
 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
 439 static const struct i2c_device_id lm3642_id[] = {
 440         {LM3642_NAME, 0},
 441         {}
 442 };
 443
 444 MODULE_DEVICE_TABLE(i2c, lm3642_id);
 445
 446 static 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 = lm3642_remove,
 454         .id_table = lm3642_id,
 455 };
 456
 457 module_i2c_driver(lm3642_i2c_driver);
 458
 459 MODULE_DESCRIPTION("Texas Instruments Flash Lighting driver for LM3642");
 460 MODULE_AUTHOR("Daniel Jeong <daniel.jeong@ti.com>");
 461 MODULE_AUTHOR("G.Shark Jeong <gshark.jeong@gmail.com>");
 462 MODULE_LICENSE("GPL v2");