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_MASK 0x18 /* Charge pump mode */ 62 #define LP5521_CP_MODE_SHIFT 3 63 #define LP5521_R_TO_BATT 0x04 /* R out: 0 = CP, 1 = Vbat */ 64 #define LP5521_CLK_INT 0x01 /* Internal clock */ 65 #define LP5521_DEFAULT_CFG (LP5521_PWM_HF | LP5521_PWRSAVE_EN) 66 67 /* Status */ 68 #define LP5521_EXT_CLK_USED 0x08 69 70 /* default R channel current register value */ 71 #define LP5521_REG_R_CURR_DEFAULT 0xAF 72 73 /* Reset register value */ 74 #define LP5521_RESET 0xFF 75 76 /* Program Memory Operations */ 77 #define LP5521_MODE_R_M 0x30 /* Operation Mode Register */ 78 #define LP5521_MODE_G_M 0x0C 79 #define LP5521_MODE_B_M 0x03 80 #define LP5521_LOAD_R 0x10 81 #define LP5521_LOAD_G 0x04 82 #define LP5521_LOAD_B 0x01 83 84 #define LP5521_R_IS_LOADING(mode) \ 85 ((mode & LP5521_MODE_R_M) == LP5521_LOAD_R) 86 #define LP5521_G_IS_LOADING(mode) \ 87 ((mode & LP5521_MODE_G_M) == LP5521_LOAD_G) 88 #define LP5521_B_IS_LOADING(mode) \ 89 ((mode & LP5521_MODE_B_M) == LP5521_LOAD_B) 90 91 #define LP5521_EXEC_R_M 0x30 /* Enable Register */ 92 #define LP5521_EXEC_G_M 0x0C 93 #define LP5521_EXEC_B_M 0x03 94 #define LP5521_EXEC_M 0x3F 95 #define LP5521_RUN_R 0x20 96 #define LP5521_RUN_G 0x08 97 #define LP5521_RUN_B 0x02 98 99 static inline void lp5521_wait_opmode_done(void) 100 { 101 /* operation mode change needs to be longer than 153 us */ 102 usleep_range(200, 300); 103 } 104 105 static inline void lp5521_wait_enable_done(void) 106 { 107 /* it takes more 488 us to update ENABLE register */ 108 usleep_range(500, 600); 109 } 110 111 static void lp5521_set_led_current(struct lp55xx_led *led, u8 led_current) 112 { 113 led->led_current = led_current; 114 lp55xx_write(led->chip, LP5521_REG_LED_CURRENT_BASE + led->chan_nr, 115 led_current); 116 } 117 118 static void lp5521_load_engine(struct lp55xx_chip *chip) 119 { 120 enum lp55xx_engine_index idx = chip->engine_idx; 121 static const u8 mask[] = { 122 [LP55XX_ENGINE_1] = LP5521_MODE_R_M, 123 [LP55XX_ENGINE_2] = LP5521_MODE_G_M, 124 [LP55XX_ENGINE_3] = LP5521_MODE_B_M, 125 }; 126 127 static const u8 val[] = { 128 [LP55XX_ENGINE_1] = LP5521_LOAD_R, 129 [LP55XX_ENGINE_2] = LP5521_LOAD_G, 130 [LP55XX_ENGINE_3] = LP5521_LOAD_B, 131 }; 132 133 lp55xx_update_bits(chip, LP5521_REG_OP_MODE, mask[idx], val[idx]); 134 135 lp5521_wait_opmode_done(); 136 } 137 138 static void lp5521_stop_all_engines(struct lp55xx_chip *chip) 139 { 140 lp55xx_write(chip, LP5521_REG_OP_MODE, 0); 141 lp5521_wait_opmode_done(); 142 } 143 144 static void lp5521_stop_engine(struct lp55xx_chip *chip) 145 { 146 enum lp55xx_engine_index idx = chip->engine_idx; 147 static const u8 mask[] = { 148 [LP55XX_ENGINE_1] = LP5521_MODE_R_M, 149 [LP55XX_ENGINE_2] = LP5521_MODE_G_M, 150 [LP55XX_ENGINE_3] = LP5521_MODE_B_M, 151 }; 152 153 lp55xx_update_bits(chip, LP5521_REG_OP_MODE, mask[idx], 0); 154 155 lp5521_wait_opmode_done(); 156 } 157 158 static void lp5521_run_engine(struct lp55xx_chip *chip, bool start) 159 { 160 int ret; 161 u8 mode; 162 u8 exec; 163 164 /* stop engine */ 165 if (!start) { 166 lp5521_stop_engine(chip); 167 lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT); 168 lp5521_wait_opmode_done(); 169 return; 170 } 171 172 /* 173 * To run the engine, 174 * operation mode and enable register should updated at the same time 175 */ 176 177 ret = lp55xx_read(chip, LP5521_REG_OP_MODE, &mode); 178 if (ret) 179 return; 180 181 ret = lp55xx_read(chip, LP5521_REG_ENABLE, &exec); 182 if (ret) 183 return; 184 185 /* change operation mode to RUN only when each engine is loading */ 186 if (LP5521_R_IS_LOADING(mode)) { 187 mode = (mode & ~LP5521_MODE_R_M) | LP5521_RUN_R; 188 exec = (exec & ~LP5521_EXEC_R_M) | LP5521_RUN_R; 189 } 190 191 if (LP5521_G_IS_LOADING(mode)) { 192 mode = (mode & ~LP5521_MODE_G_M) | LP5521_RUN_G; 193 exec = (exec & ~LP5521_EXEC_G_M) | LP5521_RUN_G; 194 } 195 196 if (LP5521_B_IS_LOADING(mode)) { 197 mode = (mode & ~LP5521_MODE_B_M) | LP5521_RUN_B; 198 exec = (exec & ~LP5521_EXEC_B_M) | LP5521_RUN_B; 199 } 200 201 lp55xx_write(chip, LP5521_REG_OP_MODE, mode); 202 lp5521_wait_opmode_done(); 203 204 lp55xx_update_bits(chip, LP5521_REG_ENABLE, LP5521_EXEC_M, exec); 205 lp5521_wait_enable_done(); 206 } 207 208 static int lp5521_update_program_memory(struct lp55xx_chip *chip, 209 const u8 *data, size_t size) 210 { 211 enum lp55xx_engine_index idx = chip->engine_idx; 212 u8 pattern[LP5521_PROGRAM_LENGTH] = {0}; 213 static const u8 addr[] = { 214 [LP55XX_ENGINE_1] = LP5521_REG_R_PROG_MEM, 215 [LP55XX_ENGINE_2] = LP5521_REG_G_PROG_MEM, 216 [LP55XX_ENGINE_3] = LP5521_REG_B_PROG_MEM, 217 }; 218 unsigned cmd; 219 char c[3]; 220 int nrchars; 221 int ret; 222 int offset = 0; 223 int i = 0; 224 225 while ((offset < size - 1) && (i < LP5521_PROGRAM_LENGTH)) { 226 /* separate sscanfs because length is working only for %s */ 227 ret = sscanf(data + offset, "%2s%n ", c, &nrchars); 228 if (ret != 1) 229 goto err; 230 231 ret = sscanf(c, "%2x", &cmd); 232 if (ret != 1) 233 goto err; 234 235 pattern[i] = (u8)cmd; 236 offset += nrchars; 237 i++; 238 } 239 240 /* Each instruction is 16bit long. Check that length is even */ 241 if (i % 2) 242 goto err; 243 244 for (i = 0; i < LP5521_PROGRAM_LENGTH; i++) { 245 ret = lp55xx_write(chip, addr[idx] + i, pattern[i]); 246 if (ret) 247 return -EINVAL; 248 } 249 250 return size; 251 252 err: 253 dev_err(&chip->cl->dev, "wrong pattern format\n"); 254 return -EINVAL; 255 } 256 257 static void lp5521_firmware_loaded(struct lp55xx_chip *chip) 258 { 259 const struct firmware *fw = chip->fw; 260 261 if (fw->size > LP5521_PROGRAM_LENGTH) { 262 dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n", 263 fw->size); 264 return; 265 } 266 267 /* 268 * Program memory sequence 269 * 1) set engine mode to "LOAD" 270 * 2) write firmware data into program memory 271 */ 272 273 lp5521_load_engine(chip); 274 lp5521_update_program_memory(chip, fw->data, fw->size); 275 } 276 277 static int lp5521_post_init_device(struct lp55xx_chip *chip) 278 { 279 int ret; 280 u8 val; 281 282 /* 283 * Make sure that the chip is reset by reading back the r channel 284 * current reg. This is dummy read is required on some platforms - 285 * otherwise further access to the R G B channels in the 286 * LP5521_REG_ENABLE register will not have any effect - strange! 287 */ 288 ret = lp55xx_read(chip, LP5521_REG_R_CURRENT, &val); 289 if (ret) { 290 dev_err(&chip->cl->dev, "error in resetting chip\n"); 291 return ret; 292 } 293 if (val != LP5521_REG_R_CURR_DEFAULT) { 294 dev_err(&chip->cl->dev, 295 "unexpected data in register (expected 0x%x got 0x%x)\n", 296 LP5521_REG_R_CURR_DEFAULT, val); 297 ret = -EINVAL; 298 return ret; 299 } 300 usleep_range(10000, 20000); 301 302 /* Set all PWMs to direct control mode */ 303 ret = lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT); 304 if (ret) 305 return ret; 306 307 /* Update configuration for the clock setting */ 308 val = LP5521_DEFAULT_CFG; 309 if (!lp55xx_is_extclk_used(chip)) 310 val |= LP5521_CLK_INT; 311 312 val |= (chip->pdata->charge_pump_mode << LP5521_CP_MODE_SHIFT) & LP5521_CP_MODE_MASK; 313 314 ret = lp55xx_write(chip, LP5521_REG_CONFIG, val); 315 if (ret) 316 return ret; 317 318 /* Initialize all channels PWM to zero -> leds off */ 319 lp55xx_write(chip, LP5521_REG_R_PWM, 0); 320 lp55xx_write(chip, LP5521_REG_G_PWM, 0); 321 lp55xx_write(chip, LP5521_REG_B_PWM, 0); 322 323 /* Set engines are set to run state when OP_MODE enables engines */ 324 ret = lp55xx_write(chip, LP5521_REG_ENABLE, LP5521_ENABLE_RUN_PROGRAM); 325 if (ret) 326 return ret; 327 328 lp5521_wait_enable_done(); 329 330 return 0; 331 } 332 333 static int lp5521_run_selftest(struct lp55xx_chip *chip, char *buf) 334 { 335 struct lp55xx_platform_data *pdata = chip->pdata; 336 int ret; 337 u8 status; 338 339 ret = lp55xx_read(chip, LP5521_REG_STATUS, &status); 340 if (ret < 0) 341 return ret; 342 343 if (pdata->clock_mode != LP55XX_CLOCK_EXT) 344 return 0; 345 346 /* Check that ext clock is really in use if requested */ 347 if ((status & LP5521_EXT_CLK_USED) == 0) 348 return -EIO; 349 350 return 0; 351 } 352 353 static int lp5521_multicolor_brightness(struct lp55xx_led *led) 354 { 355 struct lp55xx_chip *chip = led->chip; 356 int ret; 357 int i; 358 359 mutex_lock(&chip->lock); 360 for (i = 0; i < led->mc_cdev.num_colors; i++) { 361 ret = lp55xx_write(chip, 362 LP5521_REG_LED_PWM_BASE + 363 led->mc_cdev.subled_info[i].channel, 364 led->mc_cdev.subled_info[i].brightness); 365 if (ret) 366 break; 367 } 368 mutex_unlock(&chip->lock); 369 return ret; 370 } 371 372 static int lp5521_led_brightness(struct lp55xx_led *led) 373 { 374 struct lp55xx_chip *chip = led->chip; 375 int ret; 376 377 mutex_lock(&chip->lock); 378 ret = lp55xx_write(chip, LP5521_REG_LED_PWM_BASE + led->chan_nr, 379 led->brightness); 380 mutex_unlock(&chip->lock); 381 382 return ret; 383 } 384 385 static ssize_t show_engine_mode(struct device *dev, 386 struct device_attribute *attr, 387 char *buf, int nr) 388 { 389 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev)); 390 struct lp55xx_chip *chip = led->chip; 391 enum lp55xx_engine_mode mode = chip->engines[nr - 1].mode; 392 393 switch (mode) { 394 case LP55XX_ENGINE_RUN: 395 return sprintf(buf, "run\n"); 396 case LP55XX_ENGINE_LOAD: 397 return sprintf(buf, "load\n"); 398 case LP55XX_ENGINE_DISABLED: 399 default: 400 return sprintf(buf, "disabled\n"); 401 } 402 } 403 show_mode(1) 404 show_mode(2) 405 show_mode(3) 406 407 static ssize_t store_engine_mode(struct device *dev, 408 struct device_attribute *attr, 409 const char *buf, size_t len, int nr) 410 { 411 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev)); 412 struct lp55xx_chip *chip = led->chip; 413 struct lp55xx_engine *engine = &chip->engines[nr - 1]; 414 415 mutex_lock(&chip->lock); 416 417 chip->engine_idx = nr; 418 419 if (!strncmp(buf, "run", 3)) { 420 lp5521_run_engine(chip, true); 421 engine->mode = LP55XX_ENGINE_RUN; 422 } else if (!strncmp(buf, "load", 4)) { 423 lp5521_stop_engine(chip); 424 lp5521_load_engine(chip); 425 engine->mode = LP55XX_ENGINE_LOAD; 426 } else if (!strncmp(buf, "disabled", 8)) { 427 lp5521_stop_engine(chip); 428 engine->mode = LP55XX_ENGINE_DISABLED; 429 } 430 431 mutex_unlock(&chip->lock); 432 433 return len; 434 } 435 store_mode(1) 436 store_mode(2) 437 store_mode(3) 438 439 static ssize_t store_engine_load(struct device *dev, 440 struct device_attribute *attr, 441 const char *buf, size_t len, int nr) 442 { 443 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev)); 444 struct lp55xx_chip *chip = led->chip; 445 int ret; 446 447 mutex_lock(&chip->lock); 448 449 chip->engine_idx = nr; 450 lp5521_load_engine(chip); 451 ret = lp5521_update_program_memory(chip, buf, len); 452 453 mutex_unlock(&chip->lock); 454 455 return ret; 456 } 457 store_load(1) 458 store_load(2) 459 store_load(3) 460 461 static ssize_t lp5521_selftest(struct device *dev, 462 struct device_attribute *attr, 463 char *buf) 464 { 465 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev)); 466 struct lp55xx_chip *chip = led->chip; 467 int ret; 468 469 mutex_lock(&chip->lock); 470 ret = lp5521_run_selftest(chip, buf); 471 mutex_unlock(&chip->lock); 472 473 return sysfs_emit(buf, "%s\n", ret ? "FAIL" : "OK"); 474 } 475 476 /* device attributes */ 477 static LP55XX_DEV_ATTR_RW(engine1_mode, show_engine1_mode, store_engine1_mode); 478 static LP55XX_DEV_ATTR_RW(engine2_mode, show_engine2_mode, store_engine2_mode); 479 static LP55XX_DEV_ATTR_RW(engine3_mode, show_engine3_mode, store_engine3_mode); 480 static LP55XX_DEV_ATTR_WO(engine1_load, store_engine1_load); 481 static LP55XX_DEV_ATTR_WO(engine2_load, store_engine2_load); 482 static LP55XX_DEV_ATTR_WO(engine3_load, store_engine3_load); 483 static LP55XX_DEV_ATTR_RO(selftest, lp5521_selftest); 484 485 static struct attribute *lp5521_attributes[] = { 486 &dev_attr_engine1_mode.attr, 487 &dev_attr_engine2_mode.attr, 488 &dev_attr_engine3_mode.attr, 489 &dev_attr_engine1_load.attr, 490 &dev_attr_engine2_load.attr, 491 &dev_attr_engine3_load.attr, 492 &dev_attr_selftest.attr, 493 NULL 494 }; 495 496 static const struct attribute_group lp5521_group = { 497 .attrs = lp5521_attributes, 498 }; 499 500 /* Chip specific configurations */ 501 static struct lp55xx_device_config lp5521_cfg = { 502 .reset = { 503 .addr = LP5521_REG_RESET, 504 .val = LP5521_RESET, 505 }, 506 .enable = { 507 .addr = LP5521_REG_ENABLE, 508 .val = LP5521_ENABLE_DEFAULT, 509 }, 510 .max_channel = LP5521_MAX_LEDS, 511 .post_init_device = lp5521_post_init_device, 512 .brightness_fn = lp5521_led_brightness, 513 .multicolor_brightness_fn = lp5521_multicolor_brightness, 514 .set_led_current = lp5521_set_led_current, 515 .firmware_cb = lp5521_firmware_loaded, 516 .run_engine = lp5521_run_engine, 517 .dev_attr_group = &lp5521_group, 518 }; 519 520 static int lp5521_probe(struct i2c_client *client) 521 { 522 const struct i2c_device_id *id = i2c_client_get_device_id(client); 523 int ret; 524 struct lp55xx_chip *chip; 525 struct lp55xx_led *led; 526 struct lp55xx_platform_data *pdata = dev_get_platdata(&client->dev); 527 struct device_node *np = dev_of_node(&client->dev); 528 529 chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL); 530 if (!chip) 531 return -ENOMEM; 532 533 chip->cfg = &lp5521_cfg; 534 535 if (!pdata) { 536 if (np) { 537 pdata = lp55xx_of_populate_pdata(&client->dev, np, 538 chip); 539 if (IS_ERR(pdata)) 540 return PTR_ERR(pdata); 541 } else { 542 dev_err(&client->dev, "no platform data\n"); 543 return -EINVAL; 544 } 545 } 546 547 led = devm_kcalloc(&client->dev, 548 pdata->num_channels, sizeof(*led), GFP_KERNEL); 549 if (!led) 550 return -ENOMEM; 551 552 chip->cl = client; 553 chip->pdata = pdata; 554 555 mutex_init(&chip->lock); 556 557 i2c_set_clientdata(client, led); 558 559 ret = lp55xx_init_device(chip); 560 if (ret) 561 goto err_init; 562 563 dev_info(&client->dev, "%s programmable led chip found\n", id->name); 564 565 ret = lp55xx_register_leds(led, chip); 566 if (ret) 567 goto err_out; 568 569 ret = lp55xx_register_sysfs(chip); 570 if (ret) { 571 dev_err(&client->dev, "registering sysfs failed\n"); 572 goto err_out; 573 } 574 575 return 0; 576 577 err_out: 578 lp55xx_deinit_device(chip); 579 err_init: 580 return ret; 581 } 582 583 static void lp5521_remove(struct i2c_client *client) 584 { 585 struct lp55xx_led *led = i2c_get_clientdata(client); 586 struct lp55xx_chip *chip = led->chip; 587 588 lp5521_stop_all_engines(chip); 589 lp55xx_unregister_sysfs(chip); 590 lp55xx_deinit_device(chip); 591 } 592 593 static const struct i2c_device_id lp5521_id[] = { 594 { "lp5521", 0 }, /* Three channel chip */ 595 { } 596 }; 597 MODULE_DEVICE_TABLE(i2c, lp5521_id); 598 599 static const struct of_device_id of_lp5521_leds_match[] = { 600 { .compatible = "national,lp5521", }, 601 {}, 602 }; 603 604 MODULE_DEVICE_TABLE(of, of_lp5521_leds_match); 605 606 static struct i2c_driver lp5521_driver = { 607 .driver = { 608 .name = "lp5521", 609 .of_match_table = of_lp5521_leds_match, 610 }, 611 .probe = lp5521_probe, 612 .remove = lp5521_remove, 613 .id_table = lp5521_id, 614 }; 615 616 module_i2c_driver(lp5521_driver); 617 618 MODULE_AUTHOR("Mathias Nyman, Yuri Zaporozhets, Samu Onkalo"); 619 MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>"); 620 MODULE_DESCRIPTION("LP5521 LED engine"); 621 MODULE_LICENSE("GPL v2"); 622