1 // SPDX-License-Identifier: GPL-2.0 2 // Flash and torch driver for Texas Instruments LM3601X LED 3 // Flash driver chip family 4 // Copyright (C) 2018 Texas Instruments Incorporated - https://www.ti.com/ 5 6 #include <linux/delay.h> 7 #include <linux/i2c.h> 8 #include <linux/leds.h> 9 #include <linux/led-class-flash.h> 10 #include <linux/module.h> 11 #include <linux/regmap.h> 12 #include <linux/slab.h> 13 14 #define LM3601X_LED_IR 0x0 15 #define LM3601X_LED_TORCH 0x1 16 17 /* Registers */ 18 #define LM3601X_ENABLE_REG 0x01 19 #define LM3601X_CFG_REG 0x02 20 #define LM3601X_LED_FLASH_REG 0x03 21 #define LM3601X_LED_TORCH_REG 0x04 22 #define LM3601X_FLAGS_REG 0x05 23 #define LM3601X_DEV_ID_REG 0x06 24 25 #define LM3601X_SW_RESET BIT(7) 26 27 /* Enable Mode bits */ 28 #define LM3601X_MODE_STANDBY 0x00 29 #define LM3601X_MODE_IR_DRV BIT(0) 30 #define LM3601X_MODE_TORCH BIT(1) 31 #define LM3601X_MODE_STROBE (BIT(0) | BIT(1)) 32 #define LM3601X_STRB_EN BIT(2) 33 #define LM3601X_STRB_EDGE_TRIG BIT(3) 34 #define LM3601X_IVFM_EN BIT(4) 35 36 #define LM36010_BOOST_LIMIT_28 BIT(5) 37 #define LM36010_BOOST_FREQ_4MHZ BIT(6) 38 #define LM36010_BOOST_MODE_PASS BIT(7) 39 40 /* Flag Mask */ 41 #define LM3601X_FLASH_TIME_OUT BIT(0) 42 #define LM3601X_UVLO_FAULT BIT(1) 43 #define LM3601X_THERM_SHUTDOWN BIT(2) 44 #define LM3601X_THERM_CURR BIT(3) 45 #define LM36010_CURR_LIMIT BIT(4) 46 #define LM3601X_SHORT_FAULT BIT(5) 47 #define LM3601X_IVFM_TRIP BIT(6) 48 #define LM36010_OVP_FAULT BIT(7) 49 50 #define LM3601X_MAX_TORCH_I_UA 376000 51 #define LM3601X_MIN_TORCH_I_UA 2400 52 #define LM3601X_TORCH_REG_DIV 2965 53 54 #define LM3601X_MAX_STROBE_I_UA 1500000 55 #define LM3601X_MIN_STROBE_I_UA 11000 56 #define LM3601X_STROBE_REG_DIV 11800 57 58 #define LM3601X_TIMEOUT_MASK 0x1e 59 #define LM3601X_ENABLE_MASK (LM3601X_MODE_IR_DRV | LM3601X_MODE_TORCH) 60 61 #define LM3601X_LOWER_STEP_US 40000 62 #define LM3601X_UPPER_STEP_US 200000 63 #define LM3601X_MIN_TIMEOUT_US 40000 64 #define LM3601X_MAX_TIMEOUT_US 1600000 65 #define LM3601X_TIMEOUT_XOVER_US 400000 66 67 enum lm3601x_type { 68 CHIP_LM36010 = 0, 69 CHIP_LM36011, 70 }; 71 72 /** 73 * struct lm3601x_led - private lm3601x LED data 74 * @fled_cdev: flash LED class device pointer 75 * @client: Pointer to the I2C client 76 * @regmap: Devices register map 77 * @lock: Lock for reading/writing the device 78 * @flash_timeout: the timeout for the flash 79 * @last_flag: last known flags register value 80 * @torch_current_max: maximum current for the torch 81 * @flash_current_max: maximum current for the flash 82 * @max_flash_timeout: maximum timeout for the flash 83 * @led_mode: The mode to enable either IR or Torch 84 */ 85 struct lm3601x_led { 86 struct led_classdev_flash fled_cdev; 87 struct i2c_client *client; 88 struct regmap *regmap; 89 struct mutex lock; 90 91 unsigned int flash_timeout; 92 unsigned int last_flag; 93 94 u32 torch_current_max; 95 u32 flash_current_max; 96 u32 max_flash_timeout; 97 98 u32 led_mode; 99 }; 100 101 static const struct reg_default lm3601x_regmap_defs[] = { 102 { LM3601X_ENABLE_REG, 0x20 }, 103 { LM3601X_CFG_REG, 0x15 }, 104 { LM3601X_LED_FLASH_REG, 0x00 }, 105 { LM3601X_LED_TORCH_REG, 0x00 }, 106 }; 107 108 static bool lm3601x_volatile_reg(struct device *dev, unsigned int reg) 109 { 110 switch (reg) { 111 case LM3601X_FLAGS_REG: 112 return true; 113 default: 114 return false; 115 } 116 } 117 118 static const struct regmap_config lm3601x_regmap = { 119 .reg_bits = 8, 120 .val_bits = 8, 121 122 .max_register = LM3601X_DEV_ID_REG, 123 .reg_defaults = lm3601x_regmap_defs, 124 .num_reg_defaults = ARRAY_SIZE(lm3601x_regmap_defs), 125 .cache_type = REGCACHE_MAPLE, 126 .volatile_reg = lm3601x_volatile_reg, 127 }; 128 129 static struct lm3601x_led *fled_cdev_to_led(struct led_classdev_flash *fled_cdev) 130 { 131 return container_of(fled_cdev, struct lm3601x_led, fled_cdev); 132 } 133 134 static int lm3601x_read_faults(struct lm3601x_led *led) 135 { 136 int flags_val; 137 int ret; 138 139 ret = regmap_read(led->regmap, LM3601X_FLAGS_REG, &flags_val); 140 if (ret < 0) 141 return -EIO; 142 143 led->last_flag = 0; 144 145 if (flags_val & LM36010_OVP_FAULT) 146 led->last_flag |= LED_FAULT_OVER_VOLTAGE; 147 148 if (flags_val & (LM3601X_THERM_SHUTDOWN | LM3601X_THERM_CURR)) 149 led->last_flag |= LED_FAULT_OVER_TEMPERATURE; 150 151 if (flags_val & LM3601X_SHORT_FAULT) 152 led->last_flag |= LED_FAULT_SHORT_CIRCUIT; 153 154 if (flags_val & LM36010_CURR_LIMIT) 155 led->last_flag |= LED_FAULT_OVER_CURRENT; 156 157 if (flags_val & LM3601X_UVLO_FAULT) 158 led->last_flag |= LED_FAULT_UNDER_VOLTAGE; 159 160 if (flags_val & LM3601X_IVFM_TRIP) 161 led->last_flag |= LED_FAULT_INPUT_VOLTAGE; 162 163 if (flags_val & LM3601X_THERM_SHUTDOWN) 164 led->last_flag |= LED_FAULT_LED_OVER_TEMPERATURE; 165 166 return led->last_flag; 167 } 168 169 static int lm3601x_brightness_set(struct led_classdev *cdev, 170 enum led_brightness brightness) 171 { 172 struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(cdev); 173 struct lm3601x_led *led = fled_cdev_to_led(fled_cdev); 174 int ret, led_mode_val; 175 176 mutex_lock(&led->lock); 177 178 ret = lm3601x_read_faults(led); 179 if (ret < 0) 180 goto out; 181 182 if (led->led_mode == LM3601X_LED_TORCH) 183 led_mode_val = LM3601X_MODE_TORCH; 184 else 185 led_mode_val = LM3601X_MODE_IR_DRV; 186 187 if (brightness == LED_OFF) { 188 ret = regmap_update_bits(led->regmap, LM3601X_ENABLE_REG, 189 led_mode_val, LED_OFF); 190 goto out; 191 } 192 193 ret = regmap_write(led->regmap, LM3601X_LED_TORCH_REG, brightness - 1); 194 if (ret < 0) 195 goto out; 196 197 ret = regmap_update_bits(led->regmap, LM3601X_ENABLE_REG, 198 LM3601X_MODE_TORCH | LM3601X_MODE_IR_DRV, 199 led_mode_val); 200 out: 201 mutex_unlock(&led->lock); 202 return ret; 203 } 204 205 static int lm3601x_strobe_set(struct led_classdev_flash *fled_cdev, 206 bool state) 207 { 208 struct lm3601x_led *led = fled_cdev_to_led(fled_cdev); 209 int timeout_reg_val; 210 int current_timeout; 211 int ret; 212 213 mutex_lock(&led->lock); 214 215 ret = regmap_read(led->regmap, LM3601X_CFG_REG, ¤t_timeout); 216 if (ret < 0) 217 goto out; 218 219 if (led->flash_timeout >= LM3601X_TIMEOUT_XOVER_US) 220 timeout_reg_val = led->flash_timeout / LM3601X_UPPER_STEP_US + 0x07; 221 else 222 timeout_reg_val = led->flash_timeout / LM3601X_LOWER_STEP_US - 0x01; 223 224 if (led->flash_timeout != current_timeout) 225 ret = regmap_update_bits(led->regmap, LM3601X_CFG_REG, 226 LM3601X_TIMEOUT_MASK, timeout_reg_val); 227 228 if (state) 229 ret = regmap_update_bits(led->regmap, LM3601X_ENABLE_REG, 230 LM3601X_MODE_TORCH | LM3601X_MODE_IR_DRV, 231 LM3601X_MODE_STROBE); 232 else 233 ret = regmap_update_bits(led->regmap, LM3601X_ENABLE_REG, 234 LM3601X_MODE_STROBE, LED_OFF); 235 236 ret = lm3601x_read_faults(led); 237 out: 238 mutex_unlock(&led->lock); 239 return ret; 240 } 241 242 static int lm3601x_flash_brightness_set(struct led_classdev_flash *fled_cdev, 243 u32 brightness) 244 { 245 struct lm3601x_led *led = fled_cdev_to_led(fled_cdev); 246 u8 brightness_val; 247 int ret; 248 249 mutex_lock(&led->lock); 250 ret = lm3601x_read_faults(led); 251 if (ret < 0) 252 goto out; 253 254 if (brightness == LED_OFF) { 255 ret = regmap_update_bits(led->regmap, LM3601X_ENABLE_REG, 256 LM3601X_MODE_STROBE, LED_OFF); 257 goto out; 258 } 259 260 brightness_val = brightness / LM3601X_STROBE_REG_DIV; 261 262 ret = regmap_write(led->regmap, LM3601X_LED_FLASH_REG, brightness_val); 263 out: 264 mutex_unlock(&led->lock); 265 return ret; 266 } 267 268 static int lm3601x_flash_timeout_set(struct led_classdev_flash *fled_cdev, 269 u32 timeout) 270 { 271 struct lm3601x_led *led = fled_cdev_to_led(fled_cdev); 272 273 mutex_lock(&led->lock); 274 275 led->flash_timeout = timeout; 276 277 mutex_unlock(&led->lock); 278 279 return 0; 280 } 281 282 static int lm3601x_strobe_get(struct led_classdev_flash *fled_cdev, bool *state) 283 { 284 struct lm3601x_led *led = fled_cdev_to_led(fled_cdev); 285 int strobe_state; 286 int ret; 287 288 mutex_lock(&led->lock); 289 290 ret = regmap_read(led->regmap, LM3601X_ENABLE_REG, &strobe_state); 291 if (ret < 0) 292 goto out; 293 294 *state = strobe_state & LM3601X_MODE_STROBE; 295 296 out: 297 mutex_unlock(&led->lock); 298 return ret; 299 } 300 301 static int lm3601x_flash_fault_get(struct led_classdev_flash *fled_cdev, 302 u32 *fault) 303 { 304 struct lm3601x_led *led = fled_cdev_to_led(fled_cdev); 305 306 lm3601x_read_faults(led); 307 308 *fault = led->last_flag; 309 310 return 0; 311 } 312 313 static const struct led_flash_ops flash_ops = { 314 .flash_brightness_set = lm3601x_flash_brightness_set, 315 .strobe_set = lm3601x_strobe_set, 316 .strobe_get = lm3601x_strobe_get, 317 .timeout_set = lm3601x_flash_timeout_set, 318 .fault_get = lm3601x_flash_fault_get, 319 }; 320 321 static int lm3601x_register_leds(struct lm3601x_led *led, 322 struct fwnode_handle *fwnode) 323 { 324 struct led_classdev *led_cdev; 325 struct led_flash_setting *setting; 326 struct led_init_data init_data = {}; 327 328 led->fled_cdev.ops = &flash_ops; 329 330 setting = &led->fled_cdev.timeout; 331 setting->min = LM3601X_MIN_TIMEOUT_US; 332 setting->max = led->max_flash_timeout; 333 setting->step = LM3601X_LOWER_STEP_US; 334 setting->val = led->max_flash_timeout; 335 336 setting = &led->fled_cdev.brightness; 337 setting->min = LM3601X_MIN_STROBE_I_UA; 338 setting->max = led->flash_current_max; 339 setting->step = LM3601X_TORCH_REG_DIV; 340 setting->val = led->flash_current_max; 341 342 led_cdev = &led->fled_cdev.led_cdev; 343 led_cdev->brightness_set_blocking = lm3601x_brightness_set; 344 led_cdev->max_brightness = 345 DIV_ROUND_UP(led->torch_current_max - LM3601X_MIN_TORCH_I_UA + 1, 346 LM3601X_TORCH_REG_DIV); 347 led_cdev->flags |= LED_DEV_CAP_FLASH; 348 349 init_data.fwnode = fwnode; 350 init_data.devicename = led->client->name; 351 init_data.default_label = (led->led_mode == LM3601X_LED_TORCH) ? 352 "torch" : "infrared"; 353 return devm_led_classdev_flash_register_ext(&led->client->dev, 354 &led->fled_cdev, &init_data); 355 } 356 357 static int lm3601x_parse_node(struct lm3601x_led *led, 358 struct fwnode_handle **fwnode) 359 { 360 struct fwnode_handle *child = NULL; 361 int ret = -ENODEV; 362 363 child = device_get_next_child_node(&led->client->dev, child); 364 if (!child) { 365 dev_err(&led->client->dev, "No LED Child node\n"); 366 return ret; 367 } 368 369 ret = fwnode_property_read_u32(child, "reg", &led->led_mode); 370 if (ret) { 371 dev_err(&led->client->dev, "reg DT property missing\n"); 372 goto out_err; 373 } 374 375 if (led->led_mode > LM3601X_LED_TORCH || 376 led->led_mode < LM3601X_LED_IR) { 377 dev_warn(&led->client->dev, "Invalid led mode requested\n"); 378 ret = -EINVAL; 379 goto out_err; 380 } 381 382 ret = fwnode_property_read_u32(child, "led-max-microamp", 383 &led->torch_current_max); 384 if (ret) { 385 dev_warn(&led->client->dev, 386 "led-max-microamp DT property missing\n"); 387 goto out_err; 388 } 389 390 if (led->torch_current_max > LM3601X_MAX_TORCH_I_UA) { 391 dev_warn(&led->client->dev, 392 "Max torch current set too high (%d vs %d)\n", 393 led->torch_current_max, 394 LM3601X_MAX_TORCH_I_UA); 395 led->torch_current_max = LM3601X_MAX_TORCH_I_UA; 396 } 397 398 ret = fwnode_property_read_u32(child, "flash-max-microamp", 399 &led->flash_current_max); 400 if (ret) { 401 dev_warn(&led->client->dev, 402 "flash-max-microamp DT property missing\n"); 403 goto out_err; 404 } 405 406 ret = fwnode_property_read_u32(child, "flash-max-timeout-us", 407 &led->max_flash_timeout); 408 if (ret) { 409 dev_warn(&led->client->dev, 410 "flash-max-timeout-us DT property missing\n"); 411 goto out_err; 412 } 413 414 *fwnode = child; 415 416 out_err: 417 fwnode_handle_put(child); 418 return ret; 419 } 420 421 static int lm3601x_probe(struct i2c_client *client) 422 { 423 struct lm3601x_led *led; 424 struct fwnode_handle *fwnode; 425 int ret; 426 427 led = devm_kzalloc(&client->dev, sizeof(*led), GFP_KERNEL); 428 if (!led) 429 return -ENOMEM; 430 431 led->client = client; 432 i2c_set_clientdata(client, led); 433 434 ret = lm3601x_parse_node(led, &fwnode); 435 if (ret) 436 return -ENODEV; 437 438 led->regmap = devm_regmap_init_i2c(client, &lm3601x_regmap); 439 if (IS_ERR(led->regmap)) { 440 ret = PTR_ERR(led->regmap); 441 dev_err(&client->dev, 442 "Failed to allocate register map: %d\n", ret); 443 return ret; 444 } 445 446 ret = regmap_write(led->regmap, LM3601X_DEV_ID_REG, LM3601X_SW_RESET); 447 if (ret) 448 dev_warn(&client->dev, "Failed to reset the LED controller\n"); 449 450 mutex_init(&led->lock); 451 452 return lm3601x_register_leds(led, fwnode); 453 } 454 455 static void lm3601x_remove(struct i2c_client *client) 456 { 457 struct lm3601x_led *led = i2c_get_clientdata(client); 458 int ret; 459 460 ret = regmap_update_bits(led->regmap, LM3601X_ENABLE_REG, 461 LM3601X_ENABLE_MASK, LM3601X_MODE_STANDBY); 462 if (ret) 463 dev_warn(&client->dev, 464 "Failed to put into standby (%pe)\n", ERR_PTR(ret)); 465 } 466 467 static const struct i2c_device_id lm3601x_id[] = { 468 { "LM36010", CHIP_LM36010 }, 469 { "LM36011", CHIP_LM36011 }, 470 { } 471 }; 472 MODULE_DEVICE_TABLE(i2c, lm3601x_id); 473 474 static const struct of_device_id of_lm3601x_leds_match[] = { 475 { .compatible = "ti,lm36010", }, 476 { .compatible = "ti,lm36011", }, 477 { } 478 }; 479 MODULE_DEVICE_TABLE(of, of_lm3601x_leds_match); 480 481 static struct i2c_driver lm3601x_i2c_driver = { 482 .driver = { 483 .name = "lm3601x", 484 .of_match_table = of_lm3601x_leds_match, 485 }, 486 .probe = lm3601x_probe, 487 .remove = lm3601x_remove, 488 .id_table = lm3601x_id, 489 }; 490 module_i2c_driver(lm3601x_i2c_driver); 491 492 MODULE_DESCRIPTION("Texas Instruments Flash Lighting driver for LM3601X"); 493 MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>"); 494 MODULE_LICENSE("GPL v2"); 495