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 goto out; 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 ret; 150 } 151 if (ret < 0) { 152 dev_err(chip->dev, "Failed to write REG_I_CTRL Register\n"); 153 goto out; 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 out: 163 return ret; 164 } 165 166 /* torch */ 167 168 /* torch pin config for lm3642*/ 169 static ssize_t lm3642_torch_pin_store(struct device *dev, 170 struct device_attribute *attr, 171 const char *buf, size_t size) 172 { 173 ssize_t ret; 174 struct led_classdev *led_cdev = dev_get_drvdata(dev); 175 struct lm3642_chip_data *chip = 176 container_of(led_cdev, struct lm3642_chip_data, cdev_indicator); 177 unsigned int state; 178 179 ret = kstrtouint(buf, 10, &state); 180 if (ret) 181 goto out_strtoint; 182 if (state != 0) 183 state = 0x01 << TORCH_PIN_EN_SHIFT; 184 185 chip->torch_pin = state; 186 ret = regmap_update_bits(chip->regmap, REG_ENABLE, 187 TORCH_PIN_EN_MASK << TORCH_PIN_EN_SHIFT, 188 state); 189 if (ret < 0) 190 goto out; 191 192 return size; 193 out: 194 dev_err(chip->dev, "%s:i2c access fail to register\n", __func__); 195 return ret; 196 out_strtoint: 197 dev_err(chip->dev, "%s: fail to change str to int\n", __func__); 198 return ret; 199 } 200 201 static DEVICE_ATTR(torch_pin, S_IWUSR, NULL, lm3642_torch_pin_store); 202 203 static int lm3642_torch_brightness_set(struct led_classdev *cdev, 204 enum led_brightness brightness) 205 { 206 struct lm3642_chip_data *chip = 207 container_of(cdev, struct lm3642_chip_data, cdev_torch); 208 int ret; 209 210 mutex_lock(&chip->lock); 211 chip->br_torch = brightness; 212 ret = lm3642_control(chip, chip->br_torch, MODES_TORCH); 213 mutex_unlock(&chip->lock); 214 return ret; 215 } 216 217 /* flash */ 218 219 /* strobe pin config for lm3642*/ 220 static ssize_t lm3642_strobe_pin_store(struct device *dev, 221 struct device_attribute *attr, 222 const char *buf, size_t size) 223 { 224 ssize_t ret; 225 struct led_classdev *led_cdev = dev_get_drvdata(dev); 226 struct lm3642_chip_data *chip = 227 container_of(led_cdev, struct lm3642_chip_data, cdev_indicator); 228 unsigned int state; 229 230 ret = kstrtouint(buf, 10, &state); 231 if (ret) 232 goto out_strtoint; 233 if (state != 0) 234 state = 0x01 << STROBE_PIN_EN_SHIFT; 235 236 chip->strobe_pin = state; 237 ret = regmap_update_bits(chip->regmap, REG_ENABLE, 238 STROBE_PIN_EN_MASK << STROBE_PIN_EN_SHIFT, 239 state); 240 if (ret < 0) 241 goto out; 242 243 return size; 244 out: 245 dev_err(chip->dev, "%s:i2c access fail to register\n", __func__); 246 return ret; 247 out_strtoint: 248 dev_err(chip->dev, "%s: fail to change str to int\n", __func__); 249 return ret; 250 } 251 252 static DEVICE_ATTR(strobe_pin, S_IWUSR, NULL, lm3642_strobe_pin_store); 253 254 static int lm3642_strobe_brightness_set(struct led_classdev *cdev, 255 enum led_brightness brightness) 256 { 257 struct lm3642_chip_data *chip = 258 container_of(cdev, struct lm3642_chip_data, cdev_flash); 259 int ret; 260 261 mutex_lock(&chip->lock); 262 chip->br_flash = brightness; 263 ret = lm3642_control(chip, chip->br_flash, MODES_FLASH); 264 mutex_unlock(&chip->lock); 265 return ret; 266 } 267 268 /* indicator */ 269 static int lm3642_indicator_brightness_set(struct led_classdev *cdev, 270 enum led_brightness brightness) 271 { 272 struct lm3642_chip_data *chip = 273 container_of(cdev, struct lm3642_chip_data, cdev_indicator); 274 int ret; 275 276 mutex_lock(&chip->lock); 277 chip->br_indicator = brightness; 278 ret = lm3642_control(chip, chip->br_indicator, MODES_INDIC); 279 mutex_unlock(&chip->lock); 280 return ret; 281 } 282 283 static const struct regmap_config lm3642_regmap = { 284 .reg_bits = 8, 285 .val_bits = 8, 286 .max_register = REG_MAX, 287 }; 288 289 static struct attribute *lm3642_flash_attrs[] = { 290 &dev_attr_strobe_pin.attr, 291 NULL 292 }; 293 ATTRIBUTE_GROUPS(lm3642_flash); 294 295 static struct attribute *lm3642_torch_attrs[] = { 296 &dev_attr_torch_pin.attr, 297 NULL 298 }; 299 ATTRIBUTE_GROUPS(lm3642_torch); 300 301 static int lm3642_probe(struct i2c_client *client, 302 const struct i2c_device_id *id) 303 { 304 struct lm3642_platform_data *pdata = dev_get_platdata(&client->dev); 305 struct lm3642_chip_data *chip; 306 307 int err; 308 309 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { 310 dev_err(&client->dev, "i2c functionality check fail.\n"); 311 return -EOPNOTSUPP; 312 } 313 314 if (pdata == NULL) { 315 dev_err(&client->dev, "needs Platform Data.\n"); 316 return -ENODATA; 317 } 318 319 chip = devm_kzalloc(&client->dev, 320 sizeof(struct lm3642_chip_data), GFP_KERNEL); 321 if (!chip) 322 return -ENOMEM; 323 324 chip->dev = &client->dev; 325 chip->pdata = pdata; 326 327 chip->tx_pin = pdata->tx_pin; 328 chip->torch_pin = pdata->torch_pin; 329 chip->strobe_pin = pdata->strobe_pin; 330 331 chip->regmap = devm_regmap_init_i2c(client, &lm3642_regmap); 332 if (IS_ERR(chip->regmap)) { 333 err = PTR_ERR(chip->regmap); 334 dev_err(&client->dev, "Failed to allocate register map: %d\n", 335 err); 336 return err; 337 } 338 339 mutex_init(&chip->lock); 340 i2c_set_clientdata(client, chip); 341 342 err = lm3642_chip_init(chip); 343 if (err < 0) 344 goto err_out; 345 346 /* flash */ 347 chip->cdev_flash.name = "flash"; 348 chip->cdev_flash.max_brightness = 16; 349 chip->cdev_flash.brightness_set_blocking = lm3642_strobe_brightness_set; 350 chip->cdev_flash.default_trigger = "flash"; 351 chip->cdev_flash.groups = lm3642_flash_groups, 352 err = led_classdev_register((struct device *) 353 &client->dev, &chip->cdev_flash); 354 if (err < 0) { 355 dev_err(chip->dev, "failed to register flash\n"); 356 goto err_out; 357 } 358 359 /* torch */ 360 chip->cdev_torch.name = "torch"; 361 chip->cdev_torch.max_brightness = 8; 362 chip->cdev_torch.brightness_set_blocking = lm3642_torch_brightness_set; 363 chip->cdev_torch.default_trigger = "torch"; 364 chip->cdev_torch.groups = lm3642_torch_groups, 365 err = led_classdev_register((struct device *) 366 &client->dev, &chip->cdev_torch); 367 if (err < 0) { 368 dev_err(chip->dev, "failed to register torch\n"); 369 goto err_create_torch_file; 370 } 371 372 /* indicator */ 373 chip->cdev_indicator.name = "indicator"; 374 chip->cdev_indicator.max_brightness = 8; 375 chip->cdev_indicator.brightness_set_blocking = 376 lm3642_indicator_brightness_set; 377 err = led_classdev_register((struct device *) 378 &client->dev, &chip->cdev_indicator); 379 if (err < 0) { 380 dev_err(chip->dev, "failed to register indicator\n"); 381 goto err_create_indicator_file; 382 } 383 384 dev_info(&client->dev, "LM3642 is initialized\n"); 385 return 0; 386 387 err_create_indicator_file: 388 led_classdev_unregister(&chip->cdev_torch); 389 err_create_torch_file: 390 led_classdev_unregister(&chip->cdev_flash); 391 err_out: 392 return err; 393 } 394 395 static int lm3642_remove(struct i2c_client *client) 396 { 397 struct lm3642_chip_data *chip = i2c_get_clientdata(client); 398 399 led_classdev_unregister(&chip->cdev_indicator); 400 led_classdev_unregister(&chip->cdev_torch); 401 led_classdev_unregister(&chip->cdev_flash); 402 regmap_write(chip->regmap, REG_ENABLE, 0); 403 return 0; 404 } 405 406 static const struct i2c_device_id lm3642_id[] = { 407 {LM3642_NAME, 0}, 408 {} 409 }; 410 411 MODULE_DEVICE_TABLE(i2c, lm3642_id); 412 413 static struct i2c_driver lm3642_i2c_driver = { 414 .driver = { 415 .name = LM3642_NAME, 416 .pm = NULL, 417 }, 418 .probe = lm3642_probe, 419 .remove = lm3642_remove, 420 .id_table = lm3642_id, 421 }; 422 423 module_i2c_driver(lm3642_i2c_driver); 424 425 MODULE_DESCRIPTION("Texas Instruments Flash Lighting driver for LM3642"); 426 MODULE_AUTHOR("Daniel Jeong <daniel.jeong@ti.com>"); 427 MODULE_AUTHOR("G.Shark Jeong <gshark.jeong@gmail.com>"); 428 MODULE_LICENSE("GPL v2"); 429