drivers/leds/leds-lm3642.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3 * Simple driver for Texas Instruments LM3642 LED Flash driver chip
   4 * Copyright (C) 2012 Texas Instruments
   5 */
   6 #include <linux/module.h>
   7 #include <linux/delay.h>
   8 #include <linux/i2c.h>
   9 #include <linux/leds.h>
  10 #include <linux/slab.h>
  11 #include <linux/platform_device.h>
  12 #include <linux/fs.h>
  13 #include <linux/regmap.h>
  14 #include <linux/platform_data/leds-lm3642.h>
  15
  16 #define REG_FILT_TIME                   (0x0)
  17 #define REG_IVFM_MODE                   (0x1)
  18 #define REG_TORCH_TIME                  (0x6)
  19 #define REG_FLASH                       (0x8)
  20 #define REG_I_CTRL                      (0x9)
  21 #define REG_ENABLE                      (0xA)
  22 #define REG_FLAG                        (0xB)
  23 #define REG_MAX                         (0xB)
  24
  25 #define UVLO_EN_SHIFT                   (7)
  26 #define IVM_D_TH_SHIFT                  (2)
  27 #define TORCH_RAMP_UP_TIME_SHIFT        (3)
  28 #define TORCH_RAMP_DN_TIME_SHIFT        (0)
  29 #define INDUCTOR_I_LIMIT_SHIFT          (6)
  30 #define FLASH_RAMP_TIME_SHIFT           (3)
  31 #define FLASH_TOUT_TIME_SHIFT           (0)
  32 #define TORCH_I_SHIFT                   (4)
  33 #define FLASH_I_SHIFT                   (0)
  34 #define IVFM_SHIFT                      (7)
  35 #define TX_PIN_EN_SHIFT                 (6)
  36 #define STROBE_PIN_EN_SHIFT             (5)
  37 #define TORCH_PIN_EN_SHIFT              (4)
  38 #define MODE_BITS_SHIFT                 (0)
  39
  40 #define UVLO_EN_MASK                    (0x1)
  41 #define IVM_D_TH_MASK                   (0x7)
  42 #define TORCH_RAMP_UP_TIME_MASK         (0x7)
  43 #define TORCH_RAMP_DN_TIME_MASK         (0x7)
  44 #define INDUCTOR_I_LIMIT_MASK           (0x1)
  45 #define FLASH_RAMP_TIME_MASK            (0x7)
  46 #define FLASH_TOUT_TIME_MASK            (0x7)
  47 #define TORCH_I_MASK                    (0x7)
  48 #define FLASH_I_MASK                    (0xF)
  49 #define IVFM_MASK                       (0x1)
  50 #define TX_PIN_EN_MASK                  (0x1)
  51 #define STROBE_PIN_EN_MASK              (0x1)
  52 #define TORCH_PIN_EN_MASK               (0x1)
  53 #define MODE_BITS_MASK                  (0x73)
  54 #define EX_PIN_CONTROL_MASK             (0x71)
  55 #define EX_PIN_ENABLE_MASK              (0x70)
  56
  57 enum lm3642_mode {
  58         MODES_STASNDBY = 0,
  59         MODES_INDIC,
  60         MODES_TORCH,
  61         MODES_FLASH
  62 };
  63
  64 struct lm3642_chip_data {
  65         struct device *dev;
  66
  67         struct led_classdev cdev_flash;
  68         struct led_classdev cdev_torch;
  69         struct led_classdev cdev_indicator;
  70
  71         u8 br_flash;
  72         u8 br_torch;
  73         u8 br_indicator;
  74
  75         enum lm3642_torch_pin_enable torch_pin;
  76         enum lm3642_strobe_pin_enable strobe_pin;
  77         enum lm3642_tx_pin_enable tx_pin;
  78
  79         struct lm3642_platform_data *pdata;
  80         struct regmap *regmap;
  81         struct mutex lock;
  82
  83         unsigned int last_flag;
  84 };
  85
  86 /* chip initialize */
  87 static int lm3642_chip_init(struct lm3642_chip_data *chip)
  88 {
  89         int ret;
  90         struct lm3642_platform_data *pdata = chip->pdata;
  91
  92         /* set enable register */
  93         ret = regmap_update_bits(chip->regmap, REG_ENABLE, EX_PIN_ENABLE_MASK,
  94                                  pdata->tx_pin);
  95         if (ret < 0)
  96                 dev_err(chip->dev, "Failed to update REG_ENABLE Register\n");
  97         return ret;
  98 }
  99
 100 /* chip control */
 101 static int lm3642_control(struct lm3642_chip_data *chip,
 102                           u8 brightness, enum lm3642_mode opmode)
 103 {
 104         int ret;
 105
 106         ret = regmap_read(chip->regmap, REG_FLAG, &chip->last_flag);
 107         if (ret < 0) {
 108                 dev_err(chip->dev, "Failed to read REG_FLAG Register\n");
 109                 return ret;
 110         }
 111
 112         if (chip->last_flag)
 113                 dev_info(chip->dev, "Last FLAG is 0x%x\n", chip->last_flag);
 114
 115         /* brightness 0 means off-state */
 116         if (!brightness)
 117                 opmode = MODES_STASNDBY;
 118
 119         switch (opmode) {
 120         case MODES_TORCH:
 121                 ret = regmap_update_bits(chip->regmap, REG_I_CTRL,
 122                                          TORCH_I_MASK << TORCH_I_SHIFT,
 123                                          (brightness - 1) << TORCH_I_SHIFT);
 124
 125                 if (chip->torch_pin)
 126                         opmode |= (TORCH_PIN_EN_MASK << TORCH_PIN_EN_SHIFT);
 127                 break;
 128
 129         case MODES_FLASH:
 130                 ret = regmap_update_bits(chip->regmap, REG_I_CTRL,
 131                                          FLASH_I_MASK << FLASH_I_SHIFT,
 132                                          (brightness - 1) << FLASH_I_SHIFT);
 133
 134                 if (chip->strobe_pin)
 135                         opmode |= (STROBE_PIN_EN_MASK << STROBE_PIN_EN_SHIFT);
 136                 break;
 137
 138         case MODES_INDIC:
 139                 ret = regmap_update_bits(chip->regmap, REG_I_CTRL,
 140                                          TORCH_I_MASK << TORCH_I_SHIFT,
 141                                          (brightness - 1) << TORCH_I_SHIFT);
 142                 break;
 143
 144         case MODES_STASNDBY:
 145
 146                 break;
 147
 148         default:
 149                 return -EINVAL;
 150         }
 151         if (ret < 0) {
 152                 dev_err(chip->dev, "Failed to write REG_I_CTRL Register\n");
 153                 return ret;
 154         }
 155
 156         if (chip->tx_pin)
 157                 opmode |= (TX_PIN_EN_MASK << TX_PIN_EN_SHIFT);
 158
 159         ret = regmap_update_bits(chip->regmap, REG_ENABLE,
 160                                  MODE_BITS_MASK << MODE_BITS_SHIFT,
 161                                  opmode << MODE_BITS_SHIFT);
 162         return ret;
 163 }
 164
 165 /* torch */
 166
 167 /* torch pin config for lm3642 */
 168 static ssize_t lm3642_torch_pin_store(struct device *dev,
 169                                       struct device_attribute *attr,
 170                                       const char *buf, size_t size)
 171 {
 172         ssize_t ret;
 173         struct led_classdev *led_cdev = dev_get_drvdata(dev);
 174         struct lm3642_chip_data *chip =
 175             container_of(led_cdev, struct lm3642_chip_data, cdev_indicator);
 176         unsigned int state;
 177
 178         ret = kstrtouint(buf, 10, &state);
 179         if (ret)
 180                 return ret;
 181         if (state != 0)
 182                 state = 0x01 << TORCH_PIN_EN_SHIFT;
 183
 184         chip->torch_pin = state;
 185         ret = regmap_update_bits(chip->regmap, REG_ENABLE,
 186                                  TORCH_PIN_EN_MASK << TORCH_PIN_EN_SHIFT,
 187                                  state);
 188         if (ret < 0) {
 189                 dev_err(chip->dev, "%s:i2c access fail to register\n", __func__);
 190                 return ret;
 191         }
 192
 193         return size;
 194 }
 195
 196 static DEVICE_ATTR(torch_pin, S_IWUSR, NULL, lm3642_torch_pin_store);
 197
 198 static int lm3642_torch_brightness_set(struct led_classdev *cdev,
 199                                         enum led_brightness brightness)
 200 {
 201         struct lm3642_chip_data *chip =
 202             container_of(cdev, struct lm3642_chip_data, cdev_torch);
 203         int ret;
 204
 205         mutex_lock(&chip->lock);
 206         chip->br_torch = brightness;
 207         ret = lm3642_control(chip, chip->br_torch, MODES_TORCH);
 208         mutex_unlock(&chip->lock);
 209         return ret;
 210 }
 211
 212 /* flash */
 213
 214 /* strobe pin config for lm3642*/
 215 static ssize_t lm3642_strobe_pin_store(struct device *dev,
 216                                        struct device_attribute *attr,
 217                                        const char *buf, size_t size)
 218 {
 219         ssize_t ret;
 220         struct led_classdev *led_cdev = dev_get_drvdata(dev);
 221         struct lm3642_chip_data *chip =
 222             container_of(led_cdev, struct lm3642_chip_data, cdev_indicator);
 223         unsigned int state;
 224
 225         ret = kstrtouint(buf, 10, &state);
 226         if (ret)
 227                 return ret;
 228         if (state != 0)
 229                 state = 0x01 << STROBE_PIN_EN_SHIFT;
 230
 231         chip->strobe_pin = state;
 232         ret = regmap_update_bits(chip->regmap, REG_ENABLE,
 233                                  STROBE_PIN_EN_MASK << STROBE_PIN_EN_SHIFT,
 234                                  state);
 235         if (ret < 0) {
 236                 dev_err(chip->dev, "%s:i2c access fail to register\n", __func__);
 237                 return ret;
 238         }
 239
 240         return size;
 241 }
 242
 243 static DEVICE_ATTR(strobe_pin, S_IWUSR, NULL, lm3642_strobe_pin_store);
 244
 245 static int lm3642_strobe_brightness_set(struct led_classdev *cdev,
 246                                          enum led_brightness brightness)
 247 {
 248         struct lm3642_chip_data *chip =
 249             container_of(cdev, struct lm3642_chip_data, cdev_flash);
 250         int ret;
 251
 252         mutex_lock(&chip->lock);
 253         chip->br_flash = brightness;
 254         ret = lm3642_control(chip, chip->br_flash, MODES_FLASH);
 255         mutex_unlock(&chip->lock);
 256         return ret;
 257 }
 258
 259 /* indicator */
 260 static int lm3642_indicator_brightness_set(struct led_classdev *cdev,
 261                                             enum led_brightness brightness)
 262 {
 263         struct lm3642_chip_data *chip =
 264             container_of(cdev, struct lm3642_chip_data, cdev_indicator);
 265         int ret;
 266
 267         mutex_lock(&chip->lock);
 268         chip->br_indicator = brightness;
 269         ret = lm3642_control(chip, chip->br_indicator, MODES_INDIC);
 270         mutex_unlock(&chip->lock);
 271         return ret;
 272 }
 273
 274 static const struct regmap_config lm3642_regmap = {
 275         .reg_bits = 8,
 276         .val_bits = 8,
 277         .max_register = REG_MAX,
 278 };
 279
 280 static struct attribute *lm3642_flash_attrs[] = {
 281         &dev_attr_strobe_pin.attr,
 282         NULL
 283 };
 284 ATTRIBUTE_GROUPS(lm3642_flash);
 285
 286 static struct attribute *lm3642_torch_attrs[] = {
 287         &dev_attr_torch_pin.attr,
 288         NULL
 289 };
 290 ATTRIBUTE_GROUPS(lm3642_torch);
 291
 292 static int lm3642_probe(struct i2c_client *client,
 293                                   const struct i2c_device_id *id)
 294 {
 295         struct lm3642_platform_data *pdata = dev_get_platdata(&client->dev);
 296         struct lm3642_chip_data *chip;
 297
 298         int err;
 299
 300         if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
 301                 dev_err(&client->dev, "i2c functionality check fail.\n");
 302                 return -EOPNOTSUPP;
 303         }
 304
 305         if (pdata == NULL) {
 306                 dev_err(&client->dev, "needs Platform Data.\n");
 307                 return -ENODATA;
 308         }
 309
 310         chip = devm_kzalloc(&client->dev,
 311                             sizeof(struct lm3642_chip_data), GFP_KERNEL);
 312         if (!chip)
 313                 return -ENOMEM;
 314
 315         chip->dev = &client->dev;
 316         chip->pdata = pdata;
 317
 318         chip->tx_pin = pdata->tx_pin;
 319         chip->torch_pin = pdata->torch_pin;
 320         chip->strobe_pin = pdata->strobe_pin;
 321
 322         chip->regmap = devm_regmap_init_i2c(client, &lm3642_regmap);
 323         if (IS_ERR(chip->regmap)) {
 324                 err = PTR_ERR(chip->regmap);
 325                 dev_err(&client->dev, "Failed to allocate register map: %d\n",
 326                         err);
 327                 return err;
 328         }
 329
 330         mutex_init(&chip->lock);
 331         i2c_set_clientdata(client, chip);
 332
 333         err = lm3642_chip_init(chip);
 334         if (err < 0)
 335                 goto err_out;
 336
 337         /* flash */
 338         chip->cdev_flash.name = "flash";
 339         chip->cdev_flash.max_brightness = 16;
 340         chip->cdev_flash.brightness_set_blocking = lm3642_strobe_brightness_set;
 341         chip->cdev_flash.default_trigger = "flash";
 342         chip->cdev_flash.groups = lm3642_flash_groups,
 343         err = led_classdev_register((struct device *)
 344                                     &client->dev, &chip->cdev_flash);
 345         if (err < 0) {
 346                 dev_err(chip->dev, "failed to register flash\n");
 347                 goto err_out;
 348         }
 349
 350         /* torch */
 351         chip->cdev_torch.name = "torch";
 352         chip->cdev_torch.max_brightness = 8;
 353         chip->cdev_torch.brightness_set_blocking = lm3642_torch_brightness_set;
 354         chip->cdev_torch.default_trigger = "torch";
 355         chip->cdev_torch.groups = lm3642_torch_groups,
 356         err = led_classdev_register((struct device *)
 357                                     &client->dev, &chip->cdev_torch);
 358         if (err < 0) {
 359                 dev_err(chip->dev, "failed to register torch\n");
 360                 goto err_create_torch_file;
 361         }
 362
 363         /* indicator */
 364         chip->cdev_indicator.name = "indicator";
 365         chip->cdev_indicator.max_brightness = 8;
 366         chip->cdev_indicator.brightness_set_blocking =
 367                                                 lm3642_indicator_brightness_set;
 368         err = led_classdev_register((struct device *)
 369                                     &client->dev, &chip->cdev_indicator);
 370         if (err < 0) {
 371                 dev_err(chip->dev, "failed to register indicator\n");
 372                 goto err_create_indicator_file;
 373         }
 374
 375         dev_info(&client->dev, "LM3642 is initialized\n");
 376         return 0;
 377
 378 err_create_indicator_file:
 379         led_classdev_unregister(&chip->cdev_torch);
 380 err_create_torch_file:
 381         led_classdev_unregister(&chip->cdev_flash);
 382 err_out:
 383         return err;
 384 }
 385
 386 static int lm3642_remove(struct i2c_client *client)
 387 {
 388         struct lm3642_chip_data *chip = i2c_get_clientdata(client);
 389
 390         led_classdev_unregister(&chip->cdev_indicator);
 391         led_classdev_unregister(&chip->cdev_torch);
 392         led_classdev_unregister(&chip->cdev_flash);
 393         regmap_write(chip->regmap, REG_ENABLE, 0);
 394         return 0;
 395 }
 396
 397 static const struct i2c_device_id lm3642_id[] = {
 398         {LM3642_NAME, 0},
 399         {}
 400 };
 401
 402 MODULE_DEVICE_TABLE(i2c, lm3642_id);
 403
 404 static struct i2c_driver lm3642_i2c_driver = {
 405         .driver = {
 406                    .name = LM3642_NAME,
 407                    .pm = NULL,
 408                    },
 409         .probe = lm3642_probe,
 410         .remove = lm3642_remove,
 411         .id_table = lm3642_id,
 412 };
 413
 414 module_i2c_driver(lm3642_i2c_driver);
 415
 416 MODULE_DESCRIPTION("Texas Instruments Flash Lighting driver for LM3642");
 417 MODULE_AUTHOR("Daniel Jeong <daniel.jeong@ti.com>");
 418 MODULE_AUTHOR("G.Shark Jeong <gshark.jeong@gmail.com>");
 419 MODULE_LICENSE("GPL v2");