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/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
  61 enum lm3642_mode {
  62         MODES_STASNDBY = 0,
  63         MODES_INDIC,
  64         MODES_TORCH,
  65         MODES_FLASH
  66 };
  67
  68 struct 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 */
  91 static 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 */
 105 static 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);
 166 out:
 167         return ret;
 168 }
 169
 170 /* torch */
 171
 172 /* torch pin config for lm3642*/
 173 static 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;
 197 out:
 198         dev_err(chip->dev, "%s:i2c access fail to register\n", __func__);
 199         return ret;
 200 out_strtoint:
 201         dev_err(chip->dev, "%s: fail to change str to int\n", __func__);
 202         return ret;
 203 }
 204
 205 static DEVICE_ATTR(torch_pin, S_IWUSR, NULL, lm3642_torch_pin_store);
 206
 207 static 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*/
 224 static 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;
 248 out:
 249         dev_err(chip->dev, "%s:i2c access fail to register\n", __func__);
 250         return ret;
 251 out_strtoint:
 252         dev_err(chip->dev, "%s: fail to change str to int\n", __func__);
 253         return ret;
 254 }
 255
 256 static DEVICE_ATTR(strobe_pin, S_IWUSR, NULL, lm3642_strobe_pin_store);
 257
 258 static 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 */
 273 static 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
 287 static const struct regmap_config lm3642_regmap = {
 288         .reg_bits = 8,
 289         .val_bits = 8,
 290         .max_register = REG_MAX,
 291 };
 292
 293 static struct attribute *lm3642_flash_attrs[] = {
 294         &dev_attr_strobe_pin.attr,
 295         NULL
 296 };
 297 ATTRIBUTE_GROUPS(lm3642_flash);
 298
 299 static struct attribute *lm3642_torch_attrs[] = {
 300         &dev_attr_torch_pin.attr,
 301         NULL
 302 };
 303 ATTRIBUTE_GROUPS(lm3642_torch);
 304
 305 static 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
 391 err_create_indicator_file:
 392         led_classdev_unregister(&chip->cdev_torch);
 393 err_create_torch_file:
 394         led_classdev_unregister(&chip->cdev_flash);
 395 err_out:
 396         return err;
 397 }
 398
 399 static 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
 410 static const struct i2c_device_id lm3642_id[] = {
 411         {LM3642_NAME, 0},
 412         {}
 413 };
 414
 415 MODULE_DEVICE_TABLE(i2c, lm3642_id);
 416
 417 static 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
 427 module_i2c_driver(lm3642_i2c_driver);
 428
 429 MODULE_DESCRIPTION("Texas Instruments Flash Lighting driver for LM3642");
 430 MODULE_AUTHOR("Daniel Jeong <daniel.jeong@ti.com>");
 431 MODULE_AUTHOR("G.Shark Jeong <gshark.jeong@gmail.com>");
 432 MODULE_LICENSE("GPL v2");