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 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_WO(torch_pin); 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 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_WO(strobe_pin); 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 { 294 struct lm3642_platform_data *pdata = dev_get_platdata(&client->dev); 295 struct lm3642_chip_data *chip; 296 297 int err; 298 299 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { 300 dev_err(&client->dev, "i2c functionality check fail.\n"); 301 return -EOPNOTSUPP; 302 } 303 304 if (pdata == NULL) { 305 dev_err(&client->dev, "needs Platform Data.\n"); 306 return -ENODATA; 307 } 308 309 chip = devm_kzalloc(&client->dev, 310 sizeof(struct lm3642_chip_data), GFP_KERNEL); 311 if (!chip) 312 return -ENOMEM; 313 314 chip->dev = &client->dev; 315 chip->pdata = pdata; 316 317 chip->tx_pin = pdata->tx_pin; 318 chip->torch_pin = pdata->torch_pin; 319 chip->strobe_pin = pdata->strobe_pin; 320 321 chip->regmap = devm_regmap_init_i2c(client, &lm3642_regmap); 322 if (IS_ERR(chip->regmap)) { 323 err = PTR_ERR(chip->regmap); 324 dev_err(&client->dev, "Failed to allocate register map: %d\n", 325 err); 326 return err; 327 } 328 329 mutex_init(&chip->lock); 330 i2c_set_clientdata(client, chip); 331 332 err = lm3642_chip_init(chip); 333 if (err < 0) 334 goto err_out; 335 336 /* flash */ 337 chip->cdev_flash.name = "flash"; 338 chip->cdev_flash.max_brightness = 16; 339 chip->cdev_flash.brightness_set_blocking = lm3642_strobe_brightness_set; 340 chip->cdev_flash.default_trigger = "flash"; 341 chip->cdev_flash.groups = lm3642_flash_groups; 342 err = led_classdev_register(&client->dev, &chip->cdev_flash); 343 if (err < 0) { 344 dev_err(chip->dev, "failed to register flash\n"); 345 goto err_out; 346 } 347 348 /* torch */ 349 chip->cdev_torch.name = "torch"; 350 chip->cdev_torch.max_brightness = 8; 351 chip->cdev_torch.brightness_set_blocking = lm3642_torch_brightness_set; 352 chip->cdev_torch.default_trigger = "torch"; 353 chip->cdev_torch.groups = lm3642_torch_groups; 354 err = led_classdev_register(&client->dev, &chip->cdev_torch); 355 if (err < 0) { 356 dev_err(chip->dev, "failed to register torch\n"); 357 goto err_create_torch_file; 358 } 359 360 /* indicator */ 361 chip->cdev_indicator.name = "indicator"; 362 chip->cdev_indicator.max_brightness = 8; 363 chip->cdev_indicator.brightness_set_blocking = 364 lm3642_indicator_brightness_set; 365 err = led_classdev_register(&client->dev, &chip->cdev_indicator); 366 if (err < 0) { 367 dev_err(chip->dev, "failed to register indicator\n"); 368 goto err_create_indicator_file; 369 } 370 371 dev_info(&client->dev, "LM3642 is initialized\n"); 372 return 0; 373 374 err_create_indicator_file: 375 led_classdev_unregister(&chip->cdev_torch); 376 err_create_torch_file: 377 led_classdev_unregister(&chip->cdev_flash); 378 err_out: 379 return err; 380 } 381 382 static void lm3642_remove(struct i2c_client *client) 383 { 384 struct lm3642_chip_data *chip = i2c_get_clientdata(client); 385 386 led_classdev_unregister(&chip->cdev_indicator); 387 led_classdev_unregister(&chip->cdev_torch); 388 led_classdev_unregister(&chip->cdev_flash); 389 regmap_write(chip->regmap, REG_ENABLE, 0); 390 } 391 392 static const struct i2c_device_id lm3642_id[] = { 393 { LM3642_NAME }, 394 {} 395 }; 396 397 MODULE_DEVICE_TABLE(i2c, lm3642_id); 398 399 static struct i2c_driver lm3642_i2c_driver = { 400 .driver = { 401 .name = LM3642_NAME, 402 .pm = NULL, 403 }, 404 .probe = lm3642_probe, 405 .remove = lm3642_remove, 406 .id_table = lm3642_id, 407 }; 408 409 module_i2c_driver(lm3642_i2c_driver); 410 411 MODULE_DESCRIPTION("Texas Instruments Flash Lighting driver for LM3642"); 412 MODULE_AUTHOR("Daniel Jeong <daniel.jeong@ti.com>"); 413 MODULE_AUTHOR("G.Shark Jeong <gshark.jeong@gmail.com>"); 414 MODULE_LICENSE("GPL v2"); 415