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_multicolor_brightness(struct lp55xx_led *led) 353 { 354 struct lp55xx_chip *chip = led->chip; 355 int ret; 356 int i; 357 358 mutex_lock(&chip->lock); 359 for (i = 0; i < led->mc_cdev.num_colors; i++) { 360 ret = lp55xx_write(chip, 361 LP5521_REG_LED_PWM_BASE + 362 led->mc_cdev.subled_info[i].channel, 363 led->mc_cdev.subled_info[i].brightness); 364 if (ret) 365 break; 366 } 367 mutex_unlock(&chip->lock); 368 return ret; 369 } 370 371 static int lp5521_led_brightness(struct lp55xx_led *led) 372 { 373 struct lp55xx_chip *chip = led->chip; 374 int ret; 375 376 mutex_lock(&chip->lock); 377 ret = lp55xx_write(chip, LP5521_REG_LED_PWM_BASE + led->chan_nr, 378 led->brightness); 379 mutex_unlock(&chip->lock); 380 381 return ret; 382 } 383 384 static ssize_t show_engine_mode(struct device *dev, 385 struct device_attribute *attr, 386 char *buf, int nr) 387 { 388 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev)); 389 struct lp55xx_chip *chip = led->chip; 390 enum lp55xx_engine_mode mode = chip->engines[nr - 1].mode; 391 392 switch (mode) { 393 case LP55XX_ENGINE_RUN: 394 return sprintf(buf, "run\n"); 395 case LP55XX_ENGINE_LOAD: 396 return sprintf(buf, "load\n"); 397 case LP55XX_ENGINE_DISABLED: 398 default: 399 return sprintf(buf, "disabled\n"); 400 } 401 } 402 show_mode(1) 403 show_mode(2) 404 show_mode(3) 405 406 static ssize_t store_engine_mode(struct device *dev, 407 struct device_attribute *attr, 408 const char *buf, size_t len, int nr) 409 { 410 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev)); 411 struct lp55xx_chip *chip = led->chip; 412 struct lp55xx_engine *engine = &chip->engines[nr - 1]; 413 414 mutex_lock(&chip->lock); 415 416 chip->engine_idx = nr; 417 418 if (!strncmp(buf, "run", 3)) { 419 lp5521_run_engine(chip, true); 420 engine->mode = LP55XX_ENGINE_RUN; 421 } else if (!strncmp(buf, "load", 4)) { 422 lp5521_stop_engine(chip); 423 lp5521_load_engine(chip); 424 engine->mode = LP55XX_ENGINE_LOAD; 425 } else if (!strncmp(buf, "disabled", 8)) { 426 lp5521_stop_engine(chip); 427 engine->mode = LP55XX_ENGINE_DISABLED; 428 } 429 430 mutex_unlock(&chip->lock); 431 432 return len; 433 } 434 store_mode(1) 435 store_mode(2) 436 store_mode(3) 437 438 static ssize_t store_engine_load(struct device *dev, 439 struct device_attribute *attr, 440 const char *buf, size_t len, int nr) 441 { 442 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev)); 443 struct lp55xx_chip *chip = led->chip; 444 int ret; 445 446 mutex_lock(&chip->lock); 447 448 chip->engine_idx = nr; 449 lp5521_load_engine(chip); 450 ret = lp5521_update_program_memory(chip, buf, len); 451 452 mutex_unlock(&chip->lock); 453 454 return ret; 455 } 456 store_load(1) 457 store_load(2) 458 store_load(3) 459 460 static ssize_t lp5521_selftest(struct device *dev, 461 struct device_attribute *attr, 462 char *buf) 463 { 464 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev)); 465 struct lp55xx_chip *chip = led->chip; 466 int ret; 467 468 mutex_lock(&chip->lock); 469 ret = lp5521_run_selftest(chip, buf); 470 mutex_unlock(&chip->lock); 471 472 return scnprintf(buf, PAGE_SIZE, "%s\n", ret ? "FAIL" : "OK"); 473 } 474 475 /* device attributes */ 476 static LP55XX_DEV_ATTR_RW(engine1_mode, show_engine1_mode, store_engine1_mode); 477 static LP55XX_DEV_ATTR_RW(engine2_mode, show_engine2_mode, store_engine2_mode); 478 static LP55XX_DEV_ATTR_RW(engine3_mode, show_engine3_mode, store_engine3_mode); 479 static LP55XX_DEV_ATTR_WO(engine1_load, store_engine1_load); 480 static LP55XX_DEV_ATTR_WO(engine2_load, store_engine2_load); 481 static LP55XX_DEV_ATTR_WO(engine3_load, store_engine3_load); 482 static LP55XX_DEV_ATTR_RO(selftest, lp5521_selftest); 483 484 static struct attribute *lp5521_attributes[] = { 485 &dev_attr_engine1_mode.attr, 486 &dev_attr_engine2_mode.attr, 487 &dev_attr_engine3_mode.attr, 488 &dev_attr_engine1_load.attr, 489 &dev_attr_engine2_load.attr, 490 &dev_attr_engine3_load.attr, 491 &dev_attr_selftest.attr, 492 NULL 493 }; 494 495 static const struct attribute_group lp5521_group = { 496 .attrs = lp5521_attributes, 497 }; 498 499 /* Chip specific configurations */ 500 static struct lp55xx_device_config lp5521_cfg = { 501 .reset = { 502 .addr = LP5521_REG_RESET, 503 .val = LP5521_RESET, 504 }, 505 .enable = { 506 .addr = LP5521_REG_ENABLE, 507 .val = LP5521_ENABLE_DEFAULT, 508 }, 509 .max_channel = LP5521_MAX_LEDS, 510 .post_init_device = lp5521_post_init_device, 511 .brightness_fn = lp5521_led_brightness, 512 .multicolor_brightness_fn = lp5521_multicolor_brightness, 513 .set_led_current = lp5521_set_led_current, 514 .firmware_cb = lp5521_firmware_loaded, 515 .run_engine = lp5521_run_engine, 516 .dev_attr_group = &lp5521_group, 517 }; 518 519 static int lp5521_probe(struct i2c_client *client, 520 const struct i2c_device_id *id) 521 { 522 int ret; 523 struct lp55xx_chip *chip; 524 struct lp55xx_led *led; 525 struct lp55xx_platform_data *pdata = dev_get_platdata(&client->dev); 526 struct device_node *np = dev_of_node(&client->dev); 527 528 chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL); 529 if (!chip) 530 return -ENOMEM; 531 532 chip->cfg = &lp5521_cfg; 533 534 if (!pdata) { 535 if (np) { 536 pdata = lp55xx_of_populate_pdata(&client->dev, np, 537 chip); 538 if (IS_ERR(pdata)) 539 return PTR_ERR(pdata); 540 } else { 541 dev_err(&client->dev, "no platform data\n"); 542 return -EINVAL; 543 } 544 } 545 546 led = devm_kcalloc(&client->dev, 547 pdata->num_channels, sizeof(*led), GFP_KERNEL); 548 if (!led) 549 return -ENOMEM; 550 551 chip->cl = client; 552 chip->pdata = pdata; 553 554 mutex_init(&chip->lock); 555 556 i2c_set_clientdata(client, led); 557 558 ret = lp55xx_init_device(chip); 559 if (ret) 560 goto err_init; 561 562 dev_info(&client->dev, "%s programmable led chip found\n", id->name); 563 564 ret = lp55xx_register_leds(led, chip); 565 if (ret) 566 goto err_out; 567 568 ret = lp55xx_register_sysfs(chip); 569 if (ret) { 570 dev_err(&client->dev, "registering sysfs failed\n"); 571 goto err_out; 572 } 573 574 return 0; 575 576 err_out: 577 lp55xx_deinit_device(chip); 578 err_init: 579 return ret; 580 } 581 582 static void lp5521_remove(struct i2c_client *client) 583 { 584 struct lp55xx_led *led = i2c_get_clientdata(client); 585 struct lp55xx_chip *chip = led->chip; 586 587 lp5521_stop_all_engines(chip); 588 lp55xx_unregister_sysfs(chip); 589 lp55xx_deinit_device(chip); 590 } 591 592 static const struct i2c_device_id lp5521_id[] = { 593 { "lp5521", 0 }, /* Three channel chip */ 594 { } 595 }; 596 MODULE_DEVICE_TABLE(i2c, lp5521_id); 597 598 #ifdef CONFIG_OF 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 #endif 606 static struct i2c_driver lp5521_driver = { 607 .driver = { 608 .name = "lp5521", 609 .of_match_table = of_match_ptr(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