1 /* 2 * LP5521 LED chip driver. 3 * 4 * Copyright (C) 2010 Nokia Corporation 5 * Copyright (C) 2012 Texas Instruments 6 * 7 * Contact: Samu Onkalo <samu.p.onkalo@nokia.com> 8 * Milo(Woogyom) Kim <milo.kim@ti.com> 9 * 10 * This program is free software; you can redistribute it and/or 11 * modify it under the terms of the GNU General Public License 12 * version 2 as published by the Free Software Foundation. 13 * 14 * This program is distributed in the hope that it will be useful, but 15 * WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 17 * General Public License for more details. 18 * 19 * You should have received a copy of the GNU General Public License 20 * along with this program; if not, write to the Free Software 21 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 22 * 02110-1301 USA 23 */ 24 25 #include <linux/delay.h> 26 #include <linux/firmware.h> 27 #include <linux/i2c.h> 28 #include <linux/leds.h> 29 #include <linux/module.h> 30 #include <linux/mutex.h> 31 #include <linux/platform_data/leds-lp55xx.h> 32 #include <linux/slab.h> 33 #include <linux/of.h> 34 35 #include "leds-lp55xx-common.h" 36 37 #define LP5521_PROGRAM_LENGTH 32 38 #define LP5521_MAX_LEDS 3 39 #define LP5521_CMD_DIRECT 0x3F 40 41 /* Registers */ 42 #define LP5521_REG_ENABLE 0x00 43 #define LP5521_REG_OP_MODE 0x01 44 #define LP5521_REG_R_PWM 0x02 45 #define LP5521_REG_G_PWM 0x03 46 #define LP5521_REG_B_PWM 0x04 47 #define LP5521_REG_R_CURRENT 0x05 48 #define LP5521_REG_G_CURRENT 0x06 49 #define LP5521_REG_B_CURRENT 0x07 50 #define LP5521_REG_CONFIG 0x08 51 #define LP5521_REG_STATUS 0x0C 52 #define LP5521_REG_RESET 0x0D 53 #define LP5521_REG_R_PROG_MEM 0x10 54 #define LP5521_REG_G_PROG_MEM 0x30 55 #define LP5521_REG_B_PROG_MEM 0x50 56 57 /* Base register to set LED current */ 58 #define LP5521_REG_LED_CURRENT_BASE LP5521_REG_R_CURRENT 59 /* Base register to set the brightness */ 60 #define LP5521_REG_LED_PWM_BASE LP5521_REG_R_PWM 61 62 /* Bits in ENABLE register */ 63 #define LP5521_MASTER_ENABLE 0x40 /* Chip master enable */ 64 #define LP5521_LOGARITHMIC_PWM 0x80 /* Logarithmic PWM adjustment */ 65 #define LP5521_EXEC_RUN 0x2A 66 #define LP5521_ENABLE_DEFAULT \ 67 (LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM) 68 #define LP5521_ENABLE_RUN_PROGRAM \ 69 (LP5521_ENABLE_DEFAULT | LP5521_EXEC_RUN) 70 71 /* CONFIG register */ 72 #define LP5521_PWM_HF 0x40 /* PWM: 0 = 256Hz, 1 = 558Hz */ 73 #define LP5521_PWRSAVE_EN 0x20 /* 1 = Power save mode */ 74 #define LP5521_CP_MODE_OFF 0 /* Charge pump (CP) off */ 75 #define LP5521_CP_MODE_BYPASS 8 /* CP forced to bypass mode */ 76 #define LP5521_CP_MODE_1X5 0x10 /* CP forced to 1.5x mode */ 77 #define LP5521_CP_MODE_AUTO 0x18 /* Automatic mode selection */ 78 #define LP5521_R_TO_BATT 0x04 /* R out: 0 = CP, 1 = Vbat */ 79 #define LP5521_CLK_INT 0x01 /* Internal clock */ 80 #define LP5521_DEFAULT_CFG \ 81 (LP5521_PWM_HF | LP5521_PWRSAVE_EN | LP5521_CP_MODE_AUTO) 82 83 /* Status */ 84 #define LP5521_EXT_CLK_USED 0x08 85 86 /* default R channel current register value */ 87 #define LP5521_REG_R_CURR_DEFAULT 0xAF 88 89 /* Reset register value */ 90 #define LP5521_RESET 0xFF 91 92 /* Program Memory Operations */ 93 #define LP5521_MODE_R_M 0x30 /* Operation Mode Register */ 94 #define LP5521_MODE_G_M 0x0C 95 #define LP5521_MODE_B_M 0x03 96 #define LP5521_LOAD_R 0x10 97 #define LP5521_LOAD_G 0x04 98 #define LP5521_LOAD_B 0x01 99 100 #define LP5521_R_IS_LOADING(mode) \ 101 ((mode & LP5521_MODE_R_M) == LP5521_LOAD_R) 102 #define LP5521_G_IS_LOADING(mode) \ 103 ((mode & LP5521_MODE_G_M) == LP5521_LOAD_G) 104 #define LP5521_B_IS_LOADING(mode) \ 105 ((mode & LP5521_MODE_B_M) == LP5521_LOAD_B) 106 107 #define LP5521_EXEC_R_M 0x30 /* Enable Register */ 108 #define LP5521_EXEC_G_M 0x0C 109 #define LP5521_EXEC_B_M 0x03 110 #define LP5521_EXEC_M 0x3F 111 #define LP5521_RUN_R 0x20 112 #define LP5521_RUN_G 0x08 113 #define LP5521_RUN_B 0x02 114 115 static inline void lp5521_wait_opmode_done(void) 116 { 117 /* operation mode change needs to be longer than 153 us */ 118 usleep_range(200, 300); 119 } 120 121 static inline void lp5521_wait_enable_done(void) 122 { 123 /* it takes more 488 us to update ENABLE register */ 124 usleep_range(500, 600); 125 } 126 127 static void lp5521_set_led_current(struct lp55xx_led *led, u8 led_current) 128 { 129 led->led_current = led_current; 130 lp55xx_write(led->chip, LP5521_REG_LED_CURRENT_BASE + led->chan_nr, 131 led_current); 132 } 133 134 static void lp5521_load_engine(struct lp55xx_chip *chip) 135 { 136 enum lp55xx_engine_index idx = chip->engine_idx; 137 static const u8 mask[] = { 138 [LP55XX_ENGINE_1] = LP5521_MODE_R_M, 139 [LP55XX_ENGINE_2] = LP5521_MODE_G_M, 140 [LP55XX_ENGINE_3] = LP5521_MODE_B_M, 141 }; 142 143 static const u8 val[] = { 144 [LP55XX_ENGINE_1] = LP5521_LOAD_R, 145 [LP55XX_ENGINE_2] = LP5521_LOAD_G, 146 [LP55XX_ENGINE_3] = LP5521_LOAD_B, 147 }; 148 149 lp55xx_update_bits(chip, LP5521_REG_OP_MODE, mask[idx], val[idx]); 150 151 lp5521_wait_opmode_done(); 152 } 153 154 static void lp5521_stop_all_engines(struct lp55xx_chip *chip) 155 { 156 lp55xx_write(chip, LP5521_REG_OP_MODE, 0); 157 lp5521_wait_opmode_done(); 158 } 159 160 static void lp5521_stop_engine(struct lp55xx_chip *chip) 161 { 162 enum lp55xx_engine_index idx = chip->engine_idx; 163 static const u8 mask[] = { 164 [LP55XX_ENGINE_1] = LP5521_MODE_R_M, 165 [LP55XX_ENGINE_2] = LP5521_MODE_G_M, 166 [LP55XX_ENGINE_3] = LP5521_MODE_B_M, 167 }; 168 169 lp55xx_update_bits(chip, LP5521_REG_OP_MODE, mask[idx], 0); 170 171 lp5521_wait_opmode_done(); 172 } 173 174 static void lp5521_run_engine(struct lp55xx_chip *chip, bool start) 175 { 176 int ret; 177 u8 mode; 178 u8 exec; 179 180 /* stop engine */ 181 if (!start) { 182 lp5521_stop_engine(chip); 183 lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT); 184 lp5521_wait_opmode_done(); 185 return; 186 } 187 188 /* 189 * To run the engine, 190 * operation mode and enable register should updated at the same time 191 */ 192 193 ret = lp55xx_read(chip, LP5521_REG_OP_MODE, &mode); 194 if (ret) 195 return; 196 197 ret = lp55xx_read(chip, LP5521_REG_ENABLE, &exec); 198 if (ret) 199 return; 200 201 /* change operation mode to RUN only when each engine is loading */ 202 if (LP5521_R_IS_LOADING(mode)) { 203 mode = (mode & ~LP5521_MODE_R_M) | LP5521_RUN_R; 204 exec = (exec & ~LP5521_EXEC_R_M) | LP5521_RUN_R; 205 } 206 207 if (LP5521_G_IS_LOADING(mode)) { 208 mode = (mode & ~LP5521_MODE_G_M) | LP5521_RUN_G; 209 exec = (exec & ~LP5521_EXEC_G_M) | LP5521_RUN_G; 210 } 211 212 if (LP5521_B_IS_LOADING(mode)) { 213 mode = (mode & ~LP5521_MODE_B_M) | LP5521_RUN_B; 214 exec = (exec & ~LP5521_EXEC_B_M) | LP5521_RUN_B; 215 } 216 217 lp55xx_write(chip, LP5521_REG_OP_MODE, mode); 218 lp5521_wait_opmode_done(); 219 220 lp55xx_update_bits(chip, LP5521_REG_ENABLE, LP5521_EXEC_M, exec); 221 lp5521_wait_enable_done(); 222 } 223 224 static int lp5521_update_program_memory(struct lp55xx_chip *chip, 225 const u8 *data, size_t size) 226 { 227 enum lp55xx_engine_index idx = chip->engine_idx; 228 u8 pattern[LP5521_PROGRAM_LENGTH] = {0}; 229 static const u8 addr[] = { 230 [LP55XX_ENGINE_1] = LP5521_REG_R_PROG_MEM, 231 [LP55XX_ENGINE_2] = LP5521_REG_G_PROG_MEM, 232 [LP55XX_ENGINE_3] = LP5521_REG_B_PROG_MEM, 233 }; 234 unsigned cmd; 235 char c[3]; 236 int nrchars; 237 int ret; 238 int offset = 0; 239 int i = 0; 240 241 while ((offset < size - 1) && (i < LP5521_PROGRAM_LENGTH)) { 242 /* separate sscanfs because length is working only for %s */ 243 ret = sscanf(data + offset, "%2s%n ", c, &nrchars); 244 if (ret != 1) 245 goto err; 246 247 ret = sscanf(c, "%2x", &cmd); 248 if (ret != 1) 249 goto err; 250 251 pattern[i] = (u8)cmd; 252 offset += nrchars; 253 i++; 254 } 255 256 /* Each instruction is 16bit long. Check that length is even */ 257 if (i % 2) 258 goto err; 259 260 for (i = 0; i < LP5521_PROGRAM_LENGTH; i++) { 261 ret = lp55xx_write(chip, addr[idx] + i, pattern[i]); 262 if (ret) 263 return -EINVAL; 264 } 265 266 return size; 267 268 err: 269 dev_err(&chip->cl->dev, "wrong pattern format\n"); 270 return -EINVAL; 271 } 272 273 static void lp5521_firmware_loaded(struct lp55xx_chip *chip) 274 { 275 const struct firmware *fw = chip->fw; 276 277 if (fw->size > LP5521_PROGRAM_LENGTH) { 278 dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n", 279 fw->size); 280 return; 281 } 282 283 /* 284 * Program memory sequence 285 * 1) set engine mode to "LOAD" 286 * 2) write firmware data into program memory 287 */ 288 289 lp5521_load_engine(chip); 290 lp5521_update_program_memory(chip, fw->data, fw->size); 291 } 292 293 static int lp5521_post_init_device(struct lp55xx_chip *chip) 294 { 295 int ret; 296 u8 val; 297 298 /* 299 * Make sure that the chip is reset by reading back the r channel 300 * current reg. This is dummy read is required on some platforms - 301 * otherwise further access to the R G B channels in the 302 * LP5521_REG_ENABLE register will not have any effect - strange! 303 */ 304 ret = lp55xx_read(chip, LP5521_REG_R_CURRENT, &val); 305 if (ret) { 306 dev_err(&chip->cl->dev, "error in resetting chip\n"); 307 return ret; 308 } 309 if (val != LP5521_REG_R_CURR_DEFAULT) { 310 dev_err(&chip->cl->dev, 311 "unexpected data in register (expected 0x%x got 0x%x)\n", 312 LP5521_REG_R_CURR_DEFAULT, val); 313 ret = -EINVAL; 314 return ret; 315 } 316 usleep_range(10000, 20000); 317 318 /* Set all PWMs to direct control mode */ 319 ret = lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT); 320 321 /* Update configuration for the clock setting */ 322 val = LP5521_DEFAULT_CFG; 323 if (!lp55xx_is_extclk_used(chip)) 324 val |= LP5521_CLK_INT; 325 326 ret = lp55xx_write(chip, LP5521_REG_CONFIG, val); 327 if (ret) 328 return ret; 329 330 /* Initialize all channels PWM to zero -> leds off */ 331 lp55xx_write(chip, LP5521_REG_R_PWM, 0); 332 lp55xx_write(chip, LP5521_REG_G_PWM, 0); 333 lp55xx_write(chip, LP5521_REG_B_PWM, 0); 334 335 /* Set engines are set to run state when OP_MODE enables engines */ 336 ret = lp55xx_write(chip, LP5521_REG_ENABLE, LP5521_ENABLE_RUN_PROGRAM); 337 if (ret) 338 return ret; 339 340 lp5521_wait_enable_done(); 341 342 return 0; 343 } 344 345 static int lp5521_run_selftest(struct lp55xx_chip *chip, char *buf) 346 { 347 struct lp55xx_platform_data *pdata = chip->pdata; 348 int ret; 349 u8 status; 350 351 ret = lp55xx_read(chip, LP5521_REG_STATUS, &status); 352 if (ret < 0) 353 return ret; 354 355 if (pdata->clock_mode != LP55XX_CLOCK_EXT) 356 return 0; 357 358 /* Check that ext clock is really in use if requested */ 359 if ((status & LP5521_EXT_CLK_USED) == 0) 360 return -EIO; 361 362 return 0; 363 } 364 365 static int lp5521_led_brightness(struct lp55xx_led *led) 366 { 367 struct lp55xx_chip *chip = led->chip; 368 int ret; 369 370 mutex_lock(&chip->lock); 371 ret = lp55xx_write(chip, LP5521_REG_LED_PWM_BASE + led->chan_nr, 372 led->brightness); 373 mutex_unlock(&chip->lock); 374 375 return ret; 376 } 377 378 static ssize_t show_engine_mode(struct device *dev, 379 struct device_attribute *attr, 380 char *buf, int nr) 381 { 382 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev)); 383 struct lp55xx_chip *chip = led->chip; 384 enum lp55xx_engine_mode mode = chip->engines[nr - 1].mode; 385 386 switch (mode) { 387 case LP55XX_ENGINE_RUN: 388 return sprintf(buf, "run\n"); 389 case LP55XX_ENGINE_LOAD: 390 return sprintf(buf, "load\n"); 391 case LP55XX_ENGINE_DISABLED: 392 default: 393 return sprintf(buf, "disabled\n"); 394 } 395 } 396 show_mode(1) 397 show_mode(2) 398 show_mode(3) 399 400 static ssize_t store_engine_mode(struct device *dev, 401 struct device_attribute *attr, 402 const char *buf, size_t len, int nr) 403 { 404 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev)); 405 struct lp55xx_chip *chip = led->chip; 406 struct lp55xx_engine *engine = &chip->engines[nr - 1]; 407 408 mutex_lock(&chip->lock); 409 410 chip->engine_idx = nr; 411 412 if (!strncmp(buf, "run", 3)) { 413 lp5521_run_engine(chip, true); 414 engine->mode = LP55XX_ENGINE_RUN; 415 } else if (!strncmp(buf, "load", 4)) { 416 lp5521_stop_engine(chip); 417 lp5521_load_engine(chip); 418 engine->mode = LP55XX_ENGINE_LOAD; 419 } else if (!strncmp(buf, "disabled", 8)) { 420 lp5521_stop_engine(chip); 421 engine->mode = LP55XX_ENGINE_DISABLED; 422 } 423 424 mutex_unlock(&chip->lock); 425 426 return len; 427 } 428 store_mode(1) 429 store_mode(2) 430 store_mode(3) 431 432 static ssize_t store_engine_load(struct device *dev, 433 struct device_attribute *attr, 434 const char *buf, size_t len, int nr) 435 { 436 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev)); 437 struct lp55xx_chip *chip = led->chip; 438 int ret; 439 440 mutex_lock(&chip->lock); 441 442 chip->engine_idx = nr; 443 lp5521_load_engine(chip); 444 ret = lp5521_update_program_memory(chip, buf, len); 445 446 mutex_unlock(&chip->lock); 447 448 return ret; 449 } 450 store_load(1) 451 store_load(2) 452 store_load(3) 453 454 static ssize_t lp5521_selftest(struct device *dev, 455 struct device_attribute *attr, 456 char *buf) 457 { 458 struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev)); 459 struct lp55xx_chip *chip = led->chip; 460 int ret; 461 462 mutex_lock(&chip->lock); 463 ret = lp5521_run_selftest(chip, buf); 464 mutex_unlock(&chip->lock); 465 466 return scnprintf(buf, PAGE_SIZE, "%s\n", ret ? "FAIL" : "OK"); 467 } 468 469 /* device attributes */ 470 static LP55XX_DEV_ATTR_RW(engine1_mode, show_engine1_mode, store_engine1_mode); 471 static LP55XX_DEV_ATTR_RW(engine2_mode, show_engine2_mode, store_engine2_mode); 472 static LP55XX_DEV_ATTR_RW(engine3_mode, show_engine3_mode, store_engine3_mode); 473 static LP55XX_DEV_ATTR_WO(engine1_load, store_engine1_load); 474 static LP55XX_DEV_ATTR_WO(engine2_load, store_engine2_load); 475 static LP55XX_DEV_ATTR_WO(engine3_load, store_engine3_load); 476 static LP55XX_DEV_ATTR_RO(selftest, lp5521_selftest); 477 478 static struct attribute *lp5521_attributes[] = { 479 &dev_attr_engine1_mode.attr, 480 &dev_attr_engine2_mode.attr, 481 &dev_attr_engine3_mode.attr, 482 &dev_attr_engine1_load.attr, 483 &dev_attr_engine2_load.attr, 484 &dev_attr_engine3_load.attr, 485 &dev_attr_selftest.attr, 486 NULL 487 }; 488 489 static const struct attribute_group lp5521_group = { 490 .attrs = lp5521_attributes, 491 }; 492 493 /* Chip specific configurations */ 494 static struct lp55xx_device_config lp5521_cfg = { 495 .reset = { 496 .addr = LP5521_REG_RESET, 497 .val = LP5521_RESET, 498 }, 499 .enable = { 500 .addr = LP5521_REG_ENABLE, 501 .val = LP5521_ENABLE_DEFAULT, 502 }, 503 .max_channel = LP5521_MAX_LEDS, 504 .post_init_device = lp5521_post_init_device, 505 .brightness_fn = lp5521_led_brightness, 506 .set_led_current = lp5521_set_led_current, 507 .firmware_cb = lp5521_firmware_loaded, 508 .run_engine = lp5521_run_engine, 509 .dev_attr_group = &lp5521_group, 510 }; 511 512 static int lp5521_probe(struct i2c_client *client, 513 const struct i2c_device_id *id) 514 { 515 int ret; 516 struct lp55xx_chip *chip; 517 struct lp55xx_led *led; 518 struct lp55xx_platform_data *pdata = dev_get_platdata(&client->dev); 519 struct device_node *np = client->dev.of_node; 520 521 if (!pdata) { 522 if (np) { 523 pdata = lp55xx_of_populate_pdata(&client->dev, np); 524 if (IS_ERR(pdata)) 525 return PTR_ERR(pdata); 526 } else { 527 dev_err(&client->dev, "no platform data\n"); 528 return -EINVAL; 529 } 530 } 531 532 chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL); 533 if (!chip) 534 return -ENOMEM; 535 536 led = devm_kcalloc(&client->dev, 537 pdata->num_channels, sizeof(*led), GFP_KERNEL); 538 if (!led) 539 return -ENOMEM; 540 541 chip->cl = client; 542 chip->pdata = pdata; 543 chip->cfg = &lp5521_cfg; 544 545 mutex_init(&chip->lock); 546 547 i2c_set_clientdata(client, led); 548 549 ret = lp55xx_init_device(chip); 550 if (ret) 551 goto err_init; 552 553 dev_info(&client->dev, "%s programmable led chip found\n", id->name); 554 555 ret = lp55xx_register_leds(led, chip); 556 if (ret) 557 goto err_register_leds; 558 559 ret = lp55xx_register_sysfs(chip); 560 if (ret) { 561 dev_err(&client->dev, "registering sysfs failed\n"); 562 goto err_register_sysfs; 563 } 564 565 return 0; 566 567 err_register_sysfs: 568 lp55xx_unregister_leds(led, chip); 569 err_register_leds: 570 lp55xx_deinit_device(chip); 571 err_init: 572 return ret; 573 } 574 575 static int lp5521_remove(struct i2c_client *client) 576 { 577 struct lp55xx_led *led = i2c_get_clientdata(client); 578 struct lp55xx_chip *chip = led->chip; 579 580 lp5521_stop_all_engines(chip); 581 lp55xx_unregister_sysfs(chip); 582 lp55xx_unregister_leds(led, chip); 583 lp55xx_deinit_device(chip); 584 585 return 0; 586 } 587 588 static const struct i2c_device_id lp5521_id[] = { 589 { "lp5521", 0 }, /* Three channel chip */ 590 { } 591 }; 592 MODULE_DEVICE_TABLE(i2c, lp5521_id); 593 594 #ifdef CONFIG_OF 595 static const struct of_device_id of_lp5521_leds_match[] = { 596 { .compatible = "national,lp5521", }, 597 {}, 598 }; 599 600 MODULE_DEVICE_TABLE(of, of_lp5521_leds_match); 601 #endif 602 static struct i2c_driver lp5521_driver = { 603 .driver = { 604 .name = "lp5521", 605 .of_match_table = of_match_ptr(of_lp5521_leds_match), 606 }, 607 .probe = lp5521_probe, 608 .remove = lp5521_remove, 609 .id_table = lp5521_id, 610 }; 611 612 module_i2c_driver(lp5521_driver); 613 614 MODULE_AUTHOR("Mathias Nyman, Yuri Zaporozhets, Samu Onkalo"); 615 MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>"); 616 MODULE_DESCRIPTION("LP5521 LED engine"); 617 MODULE_LICENSE("GPL v2"); 618