1 /* 2 * LP5521 LED chip driver. 3 * 4 * Copyright (C) 2010 Nokia Corporation 5 * 6 * Contact: Samu Onkalo <samu.p.onkalo@nokia.com> 7 * 8 * This program is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU General Public License 10 * version 2 as published by the Free Software Foundation. 11 * 12 * This program is distributed in the hope that it will be useful, but 13 * WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with this program; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 20 * 02110-1301 USA 21 */ 22 23 #include <linux/module.h> 24 #include <linux/init.h> 25 #include <linux/i2c.h> 26 #include <linux/mutex.h> 27 #include <linux/gpio.h> 28 #include <linux/interrupt.h> 29 #include <linux/delay.h> 30 #include <linux/ctype.h> 31 #include <linux/spinlock.h> 32 #include <linux/wait.h> 33 #include <linux/leds.h> 34 #include <linux/leds-lp5521.h> 35 #include <linux/workqueue.h> 36 #include <linux/slab.h> 37 #include <linux/platform_data/leds-lp55xx.h> 38 #include <linux/firmware.h> 39 40 #include "leds-lp55xx-common.h" 41 42 #define LP5521_PROGRAM_LENGTH 32 /* in bytes */ 43 44 #define LP5521_MAX_LEDS 3 /* Maximum number of LEDs */ 45 #define LP5521_MAX_ENGINES 3 /* Maximum number of engines */ 46 47 #define LP5521_ENG_MASK_BASE 0x30 /* 00110000 */ 48 #define LP5521_ENG_STATUS_MASK 0x07 /* 00000111 */ 49 50 #define LP5521_CMD_LOAD 0x15 /* 00010101 */ 51 #define LP5521_CMD_RUN 0x2a /* 00101010 */ 52 #define LP5521_CMD_DIRECT 0x3f /* 00111111 */ 53 #define LP5521_CMD_DISABLED 0x00 /* 00000000 */ 54 55 /* Registers */ 56 #define LP5521_REG_ENABLE 0x00 57 #define LP5521_REG_OP_MODE 0x01 58 #define LP5521_REG_R_PWM 0x02 59 #define LP5521_REG_G_PWM 0x03 60 #define LP5521_REG_B_PWM 0x04 61 #define LP5521_REG_R_CURRENT 0x05 62 #define LP5521_REG_G_CURRENT 0x06 63 #define LP5521_REG_B_CURRENT 0x07 64 #define LP5521_REG_CONFIG 0x08 65 #define LP5521_REG_R_CHANNEL_PC 0x09 66 #define LP5521_REG_G_CHANNEL_PC 0x0A 67 #define LP5521_REG_B_CHANNEL_PC 0x0B 68 #define LP5521_REG_STATUS 0x0C 69 #define LP5521_REG_RESET 0x0D 70 #define LP5521_REG_GPO 0x0E 71 #define LP5521_REG_R_PROG_MEM 0x10 72 #define LP5521_REG_G_PROG_MEM 0x30 73 #define LP5521_REG_B_PROG_MEM 0x50 74 75 #define LP5521_PROG_MEM_BASE LP5521_REG_R_PROG_MEM 76 #define LP5521_PROG_MEM_SIZE 0x20 77 78 /* Base register to set LED current */ 79 #define LP5521_REG_LED_CURRENT_BASE LP5521_REG_R_CURRENT 80 81 /* Base register to set the brightness */ 82 #define LP5521_REG_LED_PWM_BASE LP5521_REG_R_PWM 83 84 /* Bits in ENABLE register */ 85 #define LP5521_MASTER_ENABLE 0x40 /* Chip master enable */ 86 #define LP5521_LOGARITHMIC_PWM 0x80 /* Logarithmic PWM adjustment */ 87 #define LP5521_EXEC_RUN 0x2A 88 #define LP5521_ENABLE_DEFAULT \ 89 (LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM) 90 #define LP5521_ENABLE_RUN_PROGRAM \ 91 (LP5521_ENABLE_DEFAULT | LP5521_EXEC_RUN) 92 93 /* Status */ 94 #define LP5521_EXT_CLK_USED 0x08 95 96 /* default R channel current register value */ 97 #define LP5521_REG_R_CURR_DEFAULT 0xAF 98 99 /* Pattern Mode */ 100 #define PATTERN_OFF 0 101 102 /* Reset register value */ 103 #define LP5521_RESET 0xFF 104 105 /* Program Memory Operations */ 106 #define LP5521_MODE_R_M 0x30 /* Operation Mode Register */ 107 #define LP5521_MODE_G_M 0x0C 108 #define LP5521_MODE_B_M 0x03 109 #define LP5521_LOAD_R 0x10 110 #define LP5521_LOAD_G 0x04 111 #define LP5521_LOAD_B 0x01 112 113 #define LP5521_R_IS_LOADING(mode) \ 114 ((mode & LP5521_MODE_R_M) == LP5521_LOAD_R) 115 #define LP5521_G_IS_LOADING(mode) \ 116 ((mode & LP5521_MODE_G_M) == LP5521_LOAD_G) 117 #define LP5521_B_IS_LOADING(mode) \ 118 ((mode & LP5521_MODE_B_M) == LP5521_LOAD_B) 119 120 #define LP5521_EXEC_R_M 0x30 /* Enable Register */ 121 #define LP5521_EXEC_G_M 0x0C 122 #define LP5521_EXEC_B_M 0x03 123 #define LP5521_EXEC_M 0x3F 124 #define LP5521_RUN_R 0x20 125 #define LP5521_RUN_G 0x08 126 #define LP5521_RUN_B 0x02 127 128 struct lp5521_led { 129 int id; 130 u8 chan_nr; 131 u8 led_current; 132 u8 max_current; 133 struct led_classdev cdev; 134 struct work_struct brightness_work; 135 u8 brightness; 136 }; 137 138 struct lp5521_chip { 139 struct lp5521_platform_data *pdata; 140 struct mutex lock; /* Serialize control */ 141 struct i2c_client *client; 142 struct lp5521_led leds[LP5521_MAX_LEDS]; 143 u8 num_channels; 144 u8 num_leds; 145 }; 146 147 static inline void lp5521_wait_opmode_done(void) 148 { 149 /* operation mode change needs to be longer than 153 us */ 150 usleep_range(200, 300); 151 } 152 153 static inline void lp5521_wait_enable_done(void) 154 { 155 /* it takes more 488 us to update ENABLE register */ 156 usleep_range(500, 600); 157 } 158 159 static void lp5521_set_led_current(struct lp55xx_led *led, u8 led_current) 160 { 161 led->led_current = led_current; 162 lp55xx_write(led->chip, LP5521_REG_LED_CURRENT_BASE + led->chan_nr, 163 led_current); 164 } 165 166 static inline int lp5521_write(struct i2c_client *client, u8 reg, u8 value) 167 { 168 return i2c_smbus_write_byte_data(client, reg, value); 169 } 170 171 static int lp5521_read(struct i2c_client *client, u8 reg, u8 *buf) 172 { 173 s32 ret; 174 175 ret = i2c_smbus_read_byte_data(client, reg); 176 if (ret < 0) 177 return ret; 178 179 *buf = ret; 180 return 0; 181 } 182 183 static void lp5521_load_engine(struct lp55xx_chip *chip) 184 { 185 enum lp55xx_engine_index idx = chip->engine_idx; 186 u8 mask[] = { 187 [LP55XX_ENGINE_1] = LP5521_MODE_R_M, 188 [LP55XX_ENGINE_2] = LP5521_MODE_G_M, 189 [LP55XX_ENGINE_3] = LP5521_MODE_B_M, 190 }; 191 192 u8 val[] = { 193 [LP55XX_ENGINE_1] = LP5521_LOAD_R, 194 [LP55XX_ENGINE_2] = LP5521_LOAD_G, 195 [LP55XX_ENGINE_3] = LP5521_LOAD_B, 196 }; 197 198 lp55xx_update_bits(chip, LP5521_REG_OP_MODE, mask[idx], val[idx]); 199 200 lp5521_wait_opmode_done(); 201 } 202 203 static void lp5521_stop_engine(struct lp55xx_chip *chip) 204 { 205 lp55xx_write(chip, LP5521_REG_OP_MODE, 0); 206 lp5521_wait_opmode_done(); 207 } 208 209 static void lp5521_run_engine(struct lp55xx_chip *chip, bool start) 210 { 211 int ret; 212 u8 mode; 213 u8 exec; 214 215 /* stop engine */ 216 if (!start) { 217 lp5521_stop_engine(chip); 218 lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT); 219 lp5521_wait_opmode_done(); 220 return; 221 } 222 223 /* 224 * To run the engine, 225 * operation mode and enable register should updated at the same time 226 */ 227 228 ret = lp55xx_read(chip, LP5521_REG_OP_MODE, &mode); 229 if (ret) 230 return; 231 232 ret = lp55xx_read(chip, LP5521_REG_ENABLE, &exec); 233 if (ret) 234 return; 235 236 /* change operation mode to RUN only when each engine is loading */ 237 if (LP5521_R_IS_LOADING(mode)) { 238 mode = (mode & ~LP5521_MODE_R_M) | LP5521_RUN_R; 239 exec = (exec & ~LP5521_EXEC_R_M) | LP5521_RUN_R; 240 } 241 242 if (LP5521_G_IS_LOADING(mode)) { 243 mode = (mode & ~LP5521_MODE_G_M) | LP5521_RUN_G; 244 exec = (exec & ~LP5521_EXEC_G_M) | LP5521_RUN_G; 245 } 246 247 if (LP5521_B_IS_LOADING(mode)) { 248 mode = (mode & ~LP5521_MODE_B_M) | LP5521_RUN_B; 249 exec = (exec & ~LP5521_EXEC_B_M) | LP5521_RUN_B; 250 } 251 252 lp55xx_write(chip, LP5521_REG_OP_MODE, mode); 253 lp5521_wait_opmode_done(); 254 255 lp55xx_update_bits(chip, LP5521_REG_ENABLE, LP5521_EXEC_M, exec); 256 lp5521_wait_enable_done(); 257 } 258 259 static int lp5521_update_program_memory(struct lp55xx_chip *chip, 260 const u8 *data, size_t size) 261 { 262 enum lp55xx_engine_index idx = chip->engine_idx; 263 u8 pattern[LP5521_PROGRAM_LENGTH] = {0}; 264 u8 addr[] = { 265 [LP55XX_ENGINE_1] = LP5521_REG_R_PROG_MEM, 266 [LP55XX_ENGINE_2] = LP5521_REG_G_PROG_MEM, 267 [LP55XX_ENGINE_3] = LP5521_REG_B_PROG_MEM, 268 }; 269 unsigned cmd; 270 char c[3]; 271 int program_size; 272 int nrchars; 273 int offset = 0; 274 int ret; 275 int i; 276 277 /* clear program memory before updating */ 278 for (i = 0; i < LP5521_PROGRAM_LENGTH; i++) 279 lp55xx_write(chip, addr[idx] + i, 0); 280 281 i = 0; 282 while ((offset < size - 1) && (i < LP5521_PROGRAM_LENGTH)) { 283 /* separate sscanfs because length is working only for %s */ 284 ret = sscanf(data + offset, "%2s%n ", c, &nrchars); 285 if (ret != 1) 286 goto err; 287 288 ret = sscanf(c, "%2x", &cmd); 289 if (ret != 1) 290 goto err; 291 292 pattern[i] = (u8)cmd; 293 offset += nrchars; 294 i++; 295 } 296 297 /* Each instruction is 16bit long. Check that length is even */ 298 if (i % 2) 299 goto err; 300 301 program_size = i; 302 for (i = 0; i < program_size; i++) 303 lp55xx_write(chip, addr[idx] + i, pattern[i]); 304 305 return 0; 306 307 err: 308 dev_err(&chip->cl->dev, "wrong pattern format\n"); 309 return -EINVAL; 310 } 311 312 static void lp5521_firmware_loaded(struct lp55xx_chip *chip) 313 { 314 const struct firmware *fw = chip->fw; 315 316 if (fw->size > LP5521_PROGRAM_LENGTH) { 317 dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n", 318 fw->size); 319 return; 320 } 321 322 /* 323 * Program momery sequence 324 * 1) set engine mode to "LOAD" 325 * 2) write firmware data into program memory 326 */ 327 328 lp5521_load_engine(chip); 329 lp5521_update_program_memory(chip, fw->data, fw->size); 330 } 331 332 static int lp5521_post_init_device(struct lp55xx_chip *chip) 333 { 334 int ret; 335 u8 val; 336 337 /* 338 * Make sure that the chip is reset by reading back the r channel 339 * current reg. This is dummy read is required on some platforms - 340 * otherwise further access to the R G B channels in the 341 * LP5521_REG_ENABLE register will not have any effect - strange! 342 */ 343 ret = lp55xx_read(chip, LP5521_REG_R_CURRENT, &val); 344 if (ret) { 345 dev_err(&chip->cl->dev, "error in resetting chip\n"); 346 return ret; 347 } 348 if (val != LP5521_REG_R_CURR_DEFAULT) { 349 dev_err(&chip->cl->dev, 350 "unexpected data in register (expected 0x%x got 0x%x)\n", 351 LP5521_REG_R_CURR_DEFAULT, val); 352 ret = -EINVAL; 353 return ret; 354 } 355 usleep_range(10000, 20000); 356 357 /* Set all PWMs to direct control mode */ 358 ret = lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT); 359 360 val = chip->pdata->update_config ? 361 : (LP5521_PWRSAVE_EN | LP5521_CP_MODE_AUTO | LP5521_R_TO_BATT); 362 ret = lp55xx_write(chip, LP5521_REG_CONFIG, val); 363 if (ret) 364 return ret; 365 366 /* Initialize all channels PWM to zero -> leds off */ 367 lp55xx_write(chip, LP5521_REG_R_PWM, 0); 368 lp55xx_write(chip, LP5521_REG_G_PWM, 0); 369 lp55xx_write(chip, LP5521_REG_B_PWM, 0); 370 371 /* Set engines are set to run state when OP_MODE enables engines */ 372 ret = lp55xx_write(chip, LP5521_REG_ENABLE, LP5521_ENABLE_RUN_PROGRAM); 373 if (ret) 374 return ret; 375 376 lp5521_wait_enable_done(); 377 378 return 0; 379 } 380 381 static int lp5521_run_selftest(struct lp5521_chip *chip, char *buf) 382 { 383 int ret; 384 u8 status; 385 386 ret = lp5521_read(chip->client, LP5521_REG_STATUS, &status); 387 if (ret < 0) 388 return ret; 389 390 /* Check that ext clock is really in use if requested */ 391 if (chip->pdata && chip->pdata->clock_mode == LP5521_CLOCK_EXT) 392 if ((status & LP5521_EXT_CLK_USED) == 0) 393 return -EIO; 394 return 0; 395 } 396 397 static void lp5521_led_brightness_work(struct work_struct *work) 398 { 399 struct lp55xx_led *led = container_of(work, struct lp55xx_led, 400 brightness_work); 401 struct lp55xx_chip *chip = led->chip; 402 403 mutex_lock(&chip->lock); 404 lp55xx_write(chip, LP5521_REG_LED_PWM_BASE + led->chan_nr, 405 led->brightness); 406 mutex_unlock(&chip->lock); 407 } 408 409 static ssize_t lp5521_selftest(struct device *dev, 410 struct device_attribute *attr, 411 char *buf) 412 { 413 struct i2c_client *client = to_i2c_client(dev); 414 struct lp5521_chip *chip = i2c_get_clientdata(client); 415 int ret; 416 417 mutex_lock(&chip->lock); 418 ret = lp5521_run_selftest(chip, buf); 419 mutex_unlock(&chip->lock); 420 return sprintf(buf, "%s\n", ret ? "FAIL" : "OK"); 421 } 422 423 static void lp5521_clear_program_memory(struct i2c_client *cl) 424 { 425 int i; 426 u8 rgb_mem[] = { 427 LP5521_REG_R_PROG_MEM, 428 LP5521_REG_G_PROG_MEM, 429 LP5521_REG_B_PROG_MEM, 430 }; 431 432 for (i = 0; i < ARRAY_SIZE(rgb_mem); i++) { 433 lp5521_write(cl, rgb_mem[i], 0); 434 lp5521_write(cl, rgb_mem[i] + 1, 0); 435 } 436 } 437 438 static void lp5521_write_program_memory(struct i2c_client *cl, 439 u8 base, u8 *rgb, int size) 440 { 441 int i; 442 443 if (!rgb || size <= 0) 444 return; 445 446 for (i = 0; i < size; i++) 447 lp5521_write(cl, base + i, *(rgb + i)); 448 449 lp5521_write(cl, base + i, 0); 450 lp5521_write(cl, base + i + 1, 0); 451 } 452 453 static inline struct lp5521_led_pattern *lp5521_get_pattern 454 (struct lp5521_chip *chip, u8 offset) 455 { 456 struct lp5521_led_pattern *ptn; 457 ptn = chip->pdata->patterns + (offset - 1); 458 return ptn; 459 } 460 461 static void lp5521_run_led_pattern(int mode, struct lp5521_chip *chip) 462 { 463 struct lp5521_led_pattern *ptn; 464 struct i2c_client *cl = chip->client; 465 int num_patterns = chip->pdata->num_patterns; 466 467 if (mode > num_patterns || !(chip->pdata->patterns)) 468 return; 469 470 if (mode == PATTERN_OFF) { 471 lp5521_write(cl, LP5521_REG_ENABLE, LP5521_ENABLE_DEFAULT); 472 usleep_range(1000, 2000); 473 lp5521_write(cl, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT); 474 } else { 475 ptn = lp5521_get_pattern(chip, mode); 476 if (!ptn) 477 return; 478 479 lp5521_write(cl, LP5521_REG_OP_MODE, LP5521_CMD_LOAD); 480 usleep_range(1000, 2000); 481 482 lp5521_clear_program_memory(cl); 483 484 lp5521_write_program_memory(cl, LP5521_REG_R_PROG_MEM, 485 ptn->r, ptn->size_r); 486 lp5521_write_program_memory(cl, LP5521_REG_G_PROG_MEM, 487 ptn->g, ptn->size_g); 488 lp5521_write_program_memory(cl, LP5521_REG_B_PROG_MEM, 489 ptn->b, ptn->size_b); 490 491 lp5521_write(cl, LP5521_REG_OP_MODE, LP5521_CMD_RUN); 492 usleep_range(1000, 2000); 493 lp5521_write(cl, LP5521_REG_ENABLE, LP5521_ENABLE_RUN_PROGRAM); 494 } 495 } 496 497 /* device attributes */ 498 static DEVICE_ATTR(selftest, S_IRUGO, lp5521_selftest, NULL); 499 500 static struct attribute *lp5521_attributes[] = { 501 &dev_attr_selftest.attr, 502 NULL 503 }; 504 505 static const struct attribute_group lp5521_group = { 506 .attrs = lp5521_attributes, 507 }; 508 509 static int lp5521_register_sysfs(struct i2c_client *client) 510 { 511 struct device *dev = &client->dev; 512 return sysfs_create_group(&dev->kobj, &lp5521_group); 513 } 514 515 static void lp5521_unregister_sysfs(struct i2c_client *client) 516 { 517 struct device *dev = &client->dev; 518 519 sysfs_remove_group(&dev->kobj, &lp5521_group); 520 } 521 522 /* Chip specific configurations */ 523 static struct lp55xx_device_config lp5521_cfg = { 524 .reset = { 525 .addr = LP5521_REG_RESET, 526 .val = LP5521_RESET, 527 }, 528 .enable = { 529 .addr = LP5521_REG_ENABLE, 530 .val = LP5521_ENABLE_DEFAULT, 531 }, 532 .max_channel = LP5521_MAX_LEDS, 533 .post_init_device = lp5521_post_init_device, 534 .brightness_work_fn = lp5521_led_brightness_work, 535 .set_led_current = lp5521_set_led_current, 536 .firmware_cb = lp5521_firmware_loaded, 537 .run_engine = lp5521_run_engine, 538 }; 539 540 static int lp5521_probe(struct i2c_client *client, 541 const struct i2c_device_id *id) 542 { 543 int ret; 544 struct lp55xx_chip *chip; 545 struct lp55xx_led *led; 546 struct lp55xx_platform_data *pdata = client->dev.platform_data; 547 548 if (!pdata) { 549 dev_err(&client->dev, "no platform data\n"); 550 return -EINVAL; 551 } 552 553 chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL); 554 if (!chip) 555 return -ENOMEM; 556 557 led = devm_kzalloc(&client->dev, 558 sizeof(*led) * pdata->num_channels, GFP_KERNEL); 559 if (!led) 560 return -ENOMEM; 561 562 chip->cl = client; 563 chip->pdata = pdata; 564 chip->cfg = &lp5521_cfg; 565 566 mutex_init(&chip->lock); 567 568 i2c_set_clientdata(client, led); 569 570 ret = lp55xx_init_device(chip); 571 if (ret) 572 goto err_init; 573 574 dev_info(&client->dev, "%s programmable led chip found\n", id->name); 575 576 ret = lp55xx_register_leds(led, chip); 577 if (ret) 578 goto err_register_leds; 579 580 ret = lp5521_register_sysfs(client); 581 if (ret) { 582 dev_err(&client->dev, "registering sysfs failed\n"); 583 goto fail2; 584 } 585 return ret; 586 fail2: 587 lp55xx_unregister_leds(led, chip); 588 err_register_leds: 589 lp55xx_deinit_device(chip); 590 err_init: 591 return ret; 592 } 593 594 static int lp5521_remove(struct i2c_client *client) 595 { 596 struct lp5521_chip *old_chip = i2c_get_clientdata(client); 597 struct lp55xx_led *led = i2c_get_clientdata(client); 598 struct lp55xx_chip *chip = led->chip; 599 600 lp5521_run_led_pattern(PATTERN_OFF, old_chip); 601 lp5521_unregister_sysfs(client); 602 603 lp55xx_unregister_leds(led, chip); 604 lp55xx_deinit_device(chip); 605 606 return 0; 607 } 608 609 static const struct i2c_device_id lp5521_id[] = { 610 { "lp5521", 0 }, /* Three channel chip */ 611 { } 612 }; 613 MODULE_DEVICE_TABLE(i2c, lp5521_id); 614 615 static struct i2c_driver lp5521_driver = { 616 .driver = { 617 .name = "lp5521", 618 }, 619 .probe = lp5521_probe, 620 .remove = lp5521_remove, 621 .id_table = lp5521_id, 622 }; 623 624 module_i2c_driver(lp5521_driver); 625 626 MODULE_AUTHOR("Mathias Nyman, Yuri Zaporozhets, Samu Onkalo"); 627 MODULE_DESCRIPTION("LP5521 LED engine"); 628 MODULE_LICENSE("GPL v2"); 629