1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * LP5521 LED chip driver. 4 * 5 * Copyright (C) 2010 Nokia Corporation 6 * Copyright (C) 2012 Texas Instruments 7 * 8 * Contact: Samu Onkalo <samu.p.onkalo@nokia.com> 9 * Milo(Woogyom) Kim <milo.kim@ti.com> 10 */ 11 12 #include <linux/delay.h> 13 #include <linux/firmware.h> 14 #include <linux/i2c.h> 15 #include <linux/leds.h> 16 #include <linux/module.h> 17 #include <linux/mutex.h> 18 #include <linux/platform_data/leds-lp55xx.h> 19 #include <linux/slab.h> 20 #include <linux/of.h> 21 22 #include "leds-lp55xx-common.h" 23 24 #define LP5521_PROGRAM_LENGTH 32 25 #define LP5521_MAX_LEDS 3 26 #define LP5521_CMD_DIRECT 0x3F 27 28 /* Registers */ 29 #define LP5521_REG_ENABLE 0x00 30 #define LP5521_REG_OP_MODE 0x01 31 #define LP5521_REG_R_PWM 0x02 32 #define LP5521_REG_G_PWM 0x03 33 #define LP5521_REG_B_PWM 0x04 34 #define LP5521_REG_R_CURRENT 0x05 35 #define LP5521_REG_G_CURRENT 0x06 36 #define LP5521_REG_B_CURRENT 0x07 37 #define LP5521_REG_CONFIG 0x08 38 #define LP5521_REG_STATUS 0x0C 39 #define LP5521_REG_RESET 0x0D 40 #define LP5521_REG_R_PROG_MEM 0x10 41 #define LP5521_REG_G_PROG_MEM 0x30 42 #define LP5521_REG_B_PROG_MEM 0x50 43 44 /* Base register to set LED current */ 45 #define LP5521_REG_LED_CURRENT_BASE LP5521_REG_R_CURRENT 46 /* Base register to set the brightness */ 47 #define LP5521_REG_LED_PWM_BASE LP5521_REG_R_PWM 48 49 /* Bits in ENABLE register */ 50 #define LP5521_MASTER_ENABLE 0x40 /* Chip master enable */ 51 #define LP5521_LOGARITHMIC_PWM 0x80 /* Logarithmic PWM adjustment */ 52 #define LP5521_EXEC_RUN 0x2A 53 #define LP5521_ENABLE_DEFAULT \ 54 (LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM) 55 #define LP5521_ENABLE_RUN_PROGRAM \ 56 (LP5521_ENABLE_DEFAULT | LP5521_EXEC_RUN) 57 58 /* CONFIG register */ 59 #define LP5521_PWM_HF 0x40 /* PWM: 0 = 256Hz, 1 = 558Hz */ 60 #define LP5521_PWRSAVE_EN 0x20 /* 1 = Power save mode */ 61 #define LP5521_CP_MODE_OFF 0 /* Charge pump (CP) off */ 62 #define LP5521_CP_MODE_BYPASS 8 /* CP forced to bypass mode */ 63 #define LP5521_CP_MODE_1X5 0x10 /* CP forced to 1.5x mode */ 64 #define LP5521_CP_MODE_AUTO 0x18 /* Automatic mode selection */ 65 #define LP5521_R_TO_BATT 0x04 /* R out: 0 = CP, 1 = Vbat */ 66 #define LP5521_CLK_INT 0x01 /* Internal clock */ 67 #define LP5521_DEFAULT_CFG \ 68 (LP5521_PWM_HF | LP5521_PWRSAVE_EN | LP5521_CP_MODE_AUTO) 69 70 /* Status */ 71 #define LP5521_EXT_CLK_USED 0x08 72 73 /* default R channel current register value */ 74 #define LP5521_REG_R_CURR_DEFAULT 0xAF 75 76 /* Reset register value */ 77 #define LP5521_RESET 0xFF 78 79 /* Program Memory Operations */ 80 #define LP5521_MODE_R_M 0x30 /* Operation Mode Register */ 81 #define LP5521_MODE_G_M 0x0C 82 #define LP5521_MODE_B_M 0x03 83 #define LP5521_LOAD_R 0x10 84 #define LP5521_LOAD_G 0x04 85 #define LP5521_LOAD_B 0x01 86 87 #define LP5521_R_IS_LOADING(mode) \ 88 ((mode & LP5521_MODE_R_M) == LP5521_LOAD_R) 89 #define LP5521_G_IS_LOADING(mode) \ 90 ((mode & LP5521_MODE_G_M) == LP5521_LOAD_G) 91 #define LP5521_B_IS_LOADING(mode) \ 92 ((mode & LP5521_MODE_B_M) == LP5521_LOAD_B) 93 94 #define LP5521_EXEC_R_M 0x30 /* Enable Register */ 95 #define LP5521_EXEC_G_M 0x0C 96 #define LP5521_EXEC_B_M 0x03 97 #define LP5521_EXEC_M 0x3F 98 #define LP5521_RUN_R 0x20 99 #define LP5521_RUN_G 0x08 100 #define LP5521_RUN_B 0x02 101 102 static inline void lp5521_wait_opmode_done(void) 103 { 104 /* operation mode change needs to be longer than 153 us */ 105 usleep_range(200, 300); 106 } 107 108 static inline void lp5521_wait_enable_done(void) 109 { 110 /* it takes more 488 us to update ENABLE register */ 111 usleep_range(500, 600); 112 } 113 114 static void lp5521_set_led_current(struct lp55xx_led *led, u8 led_current) 115 { 116 led->led_current = led_current; 117 lp55xx_write(led->chip, LP5521_REG_LED_CURRENT_BASE + led->chan_nr, 118 led_current); 119 } 120 121 static void lp5521_load_engine(struct lp55xx_chip *chip) 122 { 123 enum lp55xx_engine_index idx = chip->engine_idx; 124 static const u8 mask[] = { 125 [LP55XX_ENGINE_1] = LP5521_MODE_R_M, 126 [LP55XX_ENGINE_2] = LP5521_MODE_G_M, 127 [LP55XX_ENGINE_3] = LP5521_MODE_B_M, 128 }; 129 130 static const u8 val[] = { 131 [LP55XX_ENGINE_1] = LP5521_LOAD_R, 132 [LP55XX_ENGINE_2] = LP5521_LOAD_G, 133 [LP55XX_ENGINE_3] = LP5521_LOAD_B, 134 }; 135 136 lp55xx_update_bits(chip, LP5521_REG_OP_MODE, mask[idx], val[idx]); 137 138 lp5521_wait_opmode_done(); 139 } 140 141 static void lp5521_stop_all_engines(struct lp55xx_chip *chip) 142 { 143 lp55xx_write(chip, LP5521_REG_OP_MODE, 0); 144 lp5521_wait_opmode_done(); 145 } 146 147 static void lp5521_stop_engine(struct lp55xx_chip *chip) 148 { 149 enum lp55xx_engine_index idx = chip->engine_idx; 150 static const u8 mask[] = { 151 [LP55XX_ENGINE_1] = LP5521_MODE_R_M, 152 [LP55XX_ENGINE_2] = LP5521_MODE_G_M, 153 [LP55XX_ENGINE_3] = LP5521_MODE_B_M, 154 }; 155 156 lp55xx_update_bits(chip, LP5521_REG_OP_MODE, mask[idx], 0); 157 158 lp5521_wait_opmode_done(); 159 } 160 161 static void lp5521_run_engine(struct lp55xx_chip *chip, bool start) 162 { 163 int ret; 164 u8 mode; 165 u8 exec; 166 167 /* stop engine */ 168 if (!start) { 169 lp5521_stop_engine(chip); 170 lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT); 171 lp5521_wait_opmode_done(); 172 return; 173 } 174 175 /* 176 * To run the engine, 177 * operation mode and enable register should updated at the same time 178 */ 179 180 ret = lp55xx_read(chip, LP5521_REG_OP_MODE, &mode); 181 if (ret) 182 return; 183 184 ret = lp55xx_read(chip, LP5521_REG_ENABLE, &exec); 185 if (ret) 186 return; 187 188 /* change operation mode to RUN only when each engine is loading */ 189 if (LP5521_R_IS_LOADING(mode)) { 190 mode = (mode & ~LP5521_MODE_R_M) | LP5521_RUN_R; 191 exec = (exec & ~LP5521_EXEC_R_M) | LP5521_RUN_R; 192 } 193 194 if (LP5521_G_IS_LOADING(mode)) { 195 mode = (mode & ~LP5521_MODE_G_M) | LP5521_RUN_G; 196 exec = (exec & ~LP5521_EXEC_G_M) | LP5521_RUN_G; 197 } 198 199 if (LP5521_B_IS_LOADING(mode)) { 200 mode = (mode & ~LP5521_MODE_B_M) | LP5521_RUN_B; 201 exec = (exec & ~LP5521_EXEC_B_M) | LP5521_RUN_B; 202 } 203 204 lp55xx_write(chip, LP5521_REG_OP_MODE, mode); 205 lp5521_wait_opmode_done(); 206 207 lp55xx_update_bits(chip, LP5521_REG_ENABLE, LP5521_EXEC_M, exec); 208 lp5521_wait_enable_done(); 209 } 210 211 static int lp5521_update_program_memory(struct lp55xx_chip *chip, 212 const u8 *data, size_t size) 213 { 214 enum lp55xx_engine_index idx = chip->engine_idx; 215 u8 pattern[LP5521_PROGRAM_LENGTH] = {0}; 216 static const u8 addr[] = { 217 [LP55XX_ENGINE_1] = LP5521_REG_R_PROG_MEM, 218 [LP55XX_ENGINE_2] = LP5521_REG_G_PROG_MEM, 219 [LP55XX_ENGINE_3] = LP5521_REG_B_PROG_MEM, 220 }; 221 unsigned cmd; 222 char c[3]; 223 int nrchars; 224 int ret; 225 int offset = 0; 226 int i = 0; 227 228 while ((offset < size - 1) && (i < LP5521_PROGRAM_LENGTH)) { 229 /* separate sscanfs because length is working only for %s */ 230 ret = sscanf(data + offset, "%2s%n ", c, &nrchars); 231 if (ret != 1) 232 goto err; 233 234 ret = sscanf(c, "%2x", &cmd); 235 if (ret != 1) 236 goto err; 237 238 pattern[i] = (u8)cmd; 239 offset += nrchars; 240 i++; 241 } 242 243 /* Each instruction is 16bit long. Check that length is even */ 244 if (i % 2) 245 goto err; 246 247 for (i = 0; i < LP5521_PROGRAM_LENGTH; i++) { 248 ret = lp55xx_write(chip, addr[idx] + i, pattern[i]); 249 if (ret) 250 return -EINVAL; 251 } 252 253 return size; 254 255 err: 256 dev_err(&chip->cl->dev, "wrong pattern format\n"); 257 return -EINVAL; 258 } 259 260 static void lp5521_firmware_loaded(struct lp55xx_chip *chip) 261 { 262 const struct firmware *fw = chip->fw; 263 264 if (fw->size > LP5521_PROGRAM_LENGTH) { 265 dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n", 266 fw->size); 267 return; 268 } 269 270 /* 271 * Program memory sequence 272 * 1) set engine mode to "LOAD" 273 * 2) write firmware data into program memory 274 */ 275 276 lp5521_load_engine(chip); 277 lp5521_update_program_memory(chip, fw->data, fw->size); 278 } 279 280 static int lp5521_post_init_device(struct lp55xx_chip *chip) 281 { 282 int ret; 283 u8 val; 284 285 /* 286 * Make sure that the chip is reset by reading back the r channel 287 * current reg. This is dummy read is required on some platforms - 288 * otherwise further access to the R G B channels in the 289 * LP5521_REG_ENABLE register will not have any effect - strange! 290 */ 291 ret = lp55xx_read(chip, LP5521_REG_R_CURRENT, &val); 292 if (ret) { 293 dev_err(&chip->cl->dev, "error in resetting chip\n"); 294 return ret; 295 } 296 if (val != LP5521_REG_R_CURR_DEFAULT) { 297 dev_err(&chip->cl->dev, 298 "unexpected data in register (expected 0x%x got 0x%x)\n", 299 LP5521_REG_R_CURR_DEFAULT, val); 300 ret = -EINVAL; 301 return ret; 302 } 303 usleep_range(10000, 20000); 304 305 /* Set all PWMs to direct control mode */ 306 ret = lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT); 307 308 /* Update configuration for the clock setting */ 309 val = LP5521_DEFAULT_CFG; 310 if (!lp55xx_is_extclk_used(chip)) 311 val |= LP5521_CLK_INT; 312 313 ret = lp55xx_write(chip, LP5521_REG_CONFIG, val); 314 if (ret) 315 return ret; 316 317 /* Initialize all channels PWM to zero -> leds off */ 318 lp55xx_write(chip, LP5521_REG_R_PWM, 0); 319 lp55xx_write(chip, LP5521_REG_G_PWM, 0); 320 lp55xx_write(chip, LP5521_REG_B_PWM, 0); 321 322 /* Set engines are set to run state when OP_MODE enables engines */ 323 ret = lp55xx_write(chip, LP5521_REG_ENABLE, LP5521_ENABLE_RUN_PROGRAM); 324 if (ret) 325 return ret; 326 327 lp5521_wait_enable_done(); 328 329 return 0; 330 } 331 332 static int lp5521_run_selftest(struct lp55xx_chip *chip, char *buf) 333 { 334 struct lp55xx_platform_data *pdata = chip->pdata; 335 int ret; 336 u8 status; 337 338 ret = lp55xx_read(chip, LP5521_REG_STATUS, &status); 339 if (ret < 0) 340 return ret; 341 342 if (pdata->clock_mode != LP55XX_CLOCK_EXT) 343 return 0; 344 345 /* Check that ext clock is really in use if requested */ 346 if ((status & LP5521_EXT_CLK_USED) == 0) 347 return -EIO; 348 349 return 0; 350 } 351 352 static int lp5521_led_brightness(struct lp55xx_led *led) 353 { 354 struct lp55xx_chip *chip = led->chip; 355 int ret; 356 357 mutex_lock(&chip->lock); 358 ret = lp55xx_write(chip, LP5521_REG_LED_PWM_BASE + led->chan_nr, 359 led->brightness); 360 mutex_unlock(&chip->lock); 361 362 return ret; 363 } 364 365 static ssize_t show_engine_mode(struct device *dev, 366 struct device_attribute *attr, 367 char *buf, int nr) 368 { 369 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev)); 370 struct lp55xx_chip *chip = led->chip; 371 enum lp55xx_engine_mode mode = chip->engines[nr - 1].mode; 372 373 switch (mode) { 374 case LP55XX_ENGINE_RUN: 375 return sprintf(buf, "run\n"); 376 case LP55XX_ENGINE_LOAD: 377 return sprintf(buf, "load\n"); 378 case LP55XX_ENGINE_DISABLED: 379 default: 380 return sprintf(buf, "disabled\n"); 381 } 382 } 383 show_mode(1) 384 show_mode(2) 385 show_mode(3) 386 387 static ssize_t store_engine_mode(struct device *dev, 388 struct device_attribute *attr, 389 const char *buf, size_t len, int nr) 390 { 391 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev)); 392 struct lp55xx_chip *chip = led->chip; 393 struct lp55xx_engine *engine = &chip->engines[nr - 1]; 394 395 mutex_lock(&chip->lock); 396 397 chip->engine_idx = nr; 398 399 if (!strncmp(buf, "run", 3)) { 400 lp5521_run_engine(chip, true); 401 engine->mode = LP55XX_ENGINE_RUN; 402 } else if (!strncmp(buf, "load", 4)) { 403 lp5521_stop_engine(chip); 404 lp5521_load_engine(chip); 405 engine->mode = LP55XX_ENGINE_LOAD; 406 } else if (!strncmp(buf, "disabled", 8)) { 407 lp5521_stop_engine(chip); 408 engine->mode = LP55XX_ENGINE_DISABLED; 409 } 410 411 mutex_unlock(&chip->lock); 412 413 return len; 414 } 415 store_mode(1) 416 store_mode(2) 417 store_mode(3) 418 419 static ssize_t store_engine_load(struct device *dev, 420 struct device_attribute *attr, 421 const char *buf, size_t len, int nr) 422 { 423 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev)); 424 struct lp55xx_chip *chip = led->chip; 425 int ret; 426 427 mutex_lock(&chip->lock); 428 429 chip->engine_idx = nr; 430 lp5521_load_engine(chip); 431 ret = lp5521_update_program_memory(chip, buf, len); 432 433 mutex_unlock(&chip->lock); 434 435 return ret; 436 } 437 store_load(1) 438 store_load(2) 439 store_load(3) 440 441 static ssize_t lp5521_selftest(struct device *dev, 442 struct device_attribute *attr, 443 char *buf) 444 { 445 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev)); 446 struct lp55xx_chip *chip = led->chip; 447 int ret; 448 449 mutex_lock(&chip->lock); 450 ret = lp5521_run_selftest(chip, buf); 451 mutex_unlock(&chip->lock); 452 453 return scnprintf(buf, PAGE_SIZE, "%s\n", ret ? "FAIL" : "OK"); 454 } 455 456 /* device attributes */ 457 static LP55XX_DEV_ATTR_RW(engine1_mode, show_engine1_mode, store_engine1_mode); 458 static LP55XX_DEV_ATTR_RW(engine2_mode, show_engine2_mode, store_engine2_mode); 459 static LP55XX_DEV_ATTR_RW(engine3_mode, show_engine3_mode, store_engine3_mode); 460 static LP55XX_DEV_ATTR_WO(engine1_load, store_engine1_load); 461 static LP55XX_DEV_ATTR_WO(engine2_load, store_engine2_load); 462 static LP55XX_DEV_ATTR_WO(engine3_load, store_engine3_load); 463 static LP55XX_DEV_ATTR_RO(selftest, lp5521_selftest); 464 465 static struct attribute *lp5521_attributes[] = { 466 &dev_attr_engine1_mode.attr, 467 &dev_attr_engine2_mode.attr, 468 &dev_attr_engine3_mode.attr, 469 &dev_attr_engine1_load.attr, 470 &dev_attr_engine2_load.attr, 471 &dev_attr_engine3_load.attr, 472 &dev_attr_selftest.attr, 473 NULL 474 }; 475 476 static const struct attribute_group lp5521_group = { 477 .attrs = lp5521_attributes, 478 }; 479 480 /* Chip specific configurations */ 481 static struct lp55xx_device_config lp5521_cfg = { 482 .reset = { 483 .addr = LP5521_REG_RESET, 484 .val = LP5521_RESET, 485 }, 486 .enable = { 487 .addr = LP5521_REG_ENABLE, 488 .val = LP5521_ENABLE_DEFAULT, 489 }, 490 .max_channel = LP5521_MAX_LEDS, 491 .post_init_device = lp5521_post_init_device, 492 .brightness_fn = lp5521_led_brightness, 493 .set_led_current = lp5521_set_led_current, 494 .firmware_cb = lp5521_firmware_loaded, 495 .run_engine = lp5521_run_engine, 496 .dev_attr_group = &lp5521_group, 497 }; 498 499 static int lp5521_probe(struct i2c_client *client, 500 const struct i2c_device_id *id) 501 { 502 int ret; 503 struct lp55xx_chip *chip; 504 struct lp55xx_led *led; 505 struct lp55xx_platform_data *pdata = dev_get_platdata(&client->dev); 506 struct device_node *np = client->dev.of_node; 507 508 if (!pdata) { 509 if (np) { 510 pdata = lp55xx_of_populate_pdata(&client->dev, np); 511 if (IS_ERR(pdata)) 512 return PTR_ERR(pdata); 513 } else { 514 dev_err(&client->dev, "no platform data\n"); 515 return -EINVAL; 516 } 517 } 518 519 chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL); 520 if (!chip) 521 return -ENOMEM; 522 523 led = devm_kcalloc(&client->dev, 524 pdata->num_channels, sizeof(*led), GFP_KERNEL); 525 if (!led) 526 return -ENOMEM; 527 528 chip->cl = client; 529 chip->pdata = pdata; 530 chip->cfg = &lp5521_cfg; 531 532 mutex_init(&chip->lock); 533 534 i2c_set_clientdata(client, led); 535 536 ret = lp55xx_init_device(chip); 537 if (ret) 538 goto err_init; 539 540 dev_info(&client->dev, "%s programmable led chip found\n", id->name); 541 542 ret = lp55xx_register_leds(led, chip); 543 if (ret) 544 goto err_register_leds; 545 546 ret = lp55xx_register_sysfs(chip); 547 if (ret) { 548 dev_err(&client->dev, "registering sysfs failed\n"); 549 goto err_register_sysfs; 550 } 551 552 return 0; 553 554 err_register_sysfs: 555 lp55xx_unregister_leds(led, chip); 556 err_register_leds: 557 lp55xx_deinit_device(chip); 558 err_init: 559 return ret; 560 } 561 562 static int lp5521_remove(struct i2c_client *client) 563 { 564 struct lp55xx_led *led = i2c_get_clientdata(client); 565 struct lp55xx_chip *chip = led->chip; 566 567 lp5521_stop_all_engines(chip); 568 lp55xx_unregister_sysfs(chip); 569 lp55xx_unregister_leds(led, chip); 570 lp55xx_deinit_device(chip); 571 572 return 0; 573 } 574 575 static const struct i2c_device_id lp5521_id[] = { 576 { "lp5521", 0 }, /* Three channel chip */ 577 { } 578 }; 579 MODULE_DEVICE_TABLE(i2c, lp5521_id); 580 581 #ifdef CONFIG_OF 582 static const struct of_device_id of_lp5521_leds_match[] = { 583 { .compatible = "national,lp5521", }, 584 {}, 585 }; 586 587 MODULE_DEVICE_TABLE(of, of_lp5521_leds_match); 588 #endif 589 static struct i2c_driver lp5521_driver = { 590 .driver = { 591 .name = "lp5521", 592 .of_match_table = of_match_ptr(of_lp5521_leds_match), 593 }, 594 .probe = lp5521_probe, 595 .remove = lp5521_remove, 596 .id_table = lp5521_id, 597 }; 598 599 module_i2c_driver(lp5521_driver); 600 601 MODULE_AUTHOR("Mathias Nyman, Yuri Zaporozhets, Samu Onkalo"); 602 MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>"); 603 MODULE_DESCRIPTION("LP5521 LED engine"); 604 MODULE_LICENSE("GPL v2"); 605