drivers/leds/leds-lp5523.c

   1 /*
   2  * lp5523.c - LP5523 LED 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-lp5523.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 LP5523_REG_ENABLE               0x00
  43 #define LP5523_REG_OP_MODE              0x01
  44 #define LP5523_REG_RATIOMETRIC_MSB      0x02
  45 #define LP5523_REG_RATIOMETRIC_LSB      0x03
  46 #define LP5523_REG_ENABLE_LEDS_MSB      0x04
  47 #define LP5523_REG_ENABLE_LEDS_LSB      0x05
  48 #define LP5523_REG_LED_CNTRL_BASE       0x06
  49 #define LP5523_REG_LED_PWM_BASE         0x16
  50 #define LP5523_REG_LED_CURRENT_BASE     0x26
  51 #define LP5523_REG_CONFIG               0x36
  52 #define LP5523_REG_CHANNEL1_PC          0x37
  53 #define LP5523_REG_CHANNEL2_PC          0x38
  54 #define LP5523_REG_CHANNEL3_PC          0x39
  55 #define LP5523_REG_STATUS               0x3a
  56 #define LP5523_REG_GPO                  0x3b
  57 #define LP5523_REG_VARIABLE             0x3c
  58 #define LP5523_REG_RESET                0x3d
  59 #define LP5523_REG_TEMP_CTRL            0x3e
  60 #define LP5523_REG_TEMP_READ            0x3f
  61 #define LP5523_REG_TEMP_WRITE           0x40
  62 #define LP5523_REG_LED_TEST_CTRL        0x41
  63 #define LP5523_REG_LED_TEST_ADC         0x42
  64 #define LP5523_REG_ENG1_VARIABLE        0x45
  65 #define LP5523_REG_ENG2_VARIABLE        0x46
  66 #define LP5523_REG_ENG3_VARIABLE        0x47
  67 #define LP5523_REG_MASTER_FADER1        0x48
  68 #define LP5523_REG_MASTER_FADER2        0x49
  69 #define LP5523_REG_MASTER_FADER3        0x4a
  70 #define LP5523_REG_CH1_PROG_START       0x4c
  71 #define LP5523_REG_CH2_PROG_START       0x4d
  72 #define LP5523_REG_CH3_PROG_START       0x4e
  73 #define LP5523_REG_PROG_PAGE_SEL        0x4f
  74 #define LP5523_REG_PROG_MEM             0x50
  75
  76 #define LP5523_CMD_LOAD                 0x15 /* 00010101 */
  77 #define LP5523_CMD_RUN                  0x2a /* 00101010 */
  78 #define LP5523_CMD_DISABLED             0x00 /* 00000000 */
  79
  80 #define LP5523_ENABLE                   0x40
  81 #define LP5523_AUTO_INC                 0x40
  82 #define LP5523_PWR_SAVE                 0x20
  83 #define LP5523_PWM_PWR_SAVE             0x04
  84 #define LP5523_CP_1                     0x08
  85 #define LP5523_CP_1_5                   0x10
  86 #define LP5523_CP_AUTO                  0x18
  87 #define LP5523_INT_CLK                  0x01
  88 #define LP5523_AUTO_CLK                 0x02
  89 #define LP5523_EN_LEDTEST               0x80
  90 #define LP5523_LEDTEST_DONE             0x80
  91 #define LP5523_RESET                    0xFF
  92
  93 #define LP5523_DEFAULT_CURRENT          50 /* microAmps */
  94 #define LP5523_PROGRAM_LENGTH           32 /* in bytes */
  95 #define LP5523_PROGRAM_PAGES            6
  96 #define LP5523_ADC_SHORTCIRC_LIM        80
  97
  98 #define LP5523_MAX_LEDS                 9
  99 #define LP5523_ENGINES                  3
 100
 101 #define LP5523_ENG_MASK_BASE            0x30 /* 00110000 */
 102
 103 #define LP5523_ENG_STATUS_MASK          0x07 /* 00000111 */
 104
 105 #define LP5523_IRQ_FLAGS                IRQF_TRIGGER_FALLING
 106
 107 #define LP5523_EXT_CLK_USED             0x08
 108
 109 #define LED_ACTIVE(mux, led)            (!!(mux & (0x0001 << led)))
 110 #define SHIFT_MASK(id)                  (((id) - 1) * 2)
 111
 112 /* Memory Page Selection */
 113 #define LP5523_PAGE_ENG1                0
 114 #define LP5523_PAGE_ENG2                1
 115 #define LP5523_PAGE_ENG3                2
 116
 117 /* Program Memory Operations */
 118 #define LP5523_MODE_ENG1_M              0x30    /* Operation Mode Register */
 119 #define LP5523_MODE_ENG2_M              0x0C
 120 #define LP5523_MODE_ENG3_M              0x03
 121 #define LP5523_LOAD_ENG1                0x10
 122 #define LP5523_LOAD_ENG2                0x04
 123 #define LP5523_LOAD_ENG3                0x01
 124
 125 #define LP5523_ENG1_IS_LOADING(mode)    \
 126         ((mode & LP5523_MODE_ENG1_M) == LP5523_LOAD_ENG1)
 127 #define LP5523_ENG2_IS_LOADING(mode)    \
 128         ((mode & LP5523_MODE_ENG2_M) == LP5523_LOAD_ENG2)
 129 #define LP5523_ENG3_IS_LOADING(mode)    \
 130         ((mode & LP5523_MODE_ENG3_M) == LP5523_LOAD_ENG3)
 131
 132 #define LP5523_EXEC_ENG1_M              0x30    /* Enable Register */
 133 #define LP5523_EXEC_ENG2_M              0x0C
 134 #define LP5523_EXEC_ENG3_M              0x03
 135 #define LP5523_EXEC_M                   0x3F
 136 #define LP5523_RUN_ENG1                 0x20
 137 #define LP5523_RUN_ENG2                 0x08
 138 #define LP5523_RUN_ENG3                 0x02
 139
 140 enum lp5523_chip_id {
 141         LP5523,
 142         LP55231,
 143 };
 144
 145 struct lp5523_led {
 146         int                     id;
 147         u8                      chan_nr;
 148         u8                      led_current;
 149         u8                      max_current;
 150         struct led_classdev     cdev;
 151         struct work_struct      brightness_work;
 152         u8                      brightness;
 153 };
 154
 155 struct lp5523_chip {
 156         struct mutex            lock; /* Serialize control */
 157         struct i2c_client       *client;
 158         struct lp5523_led       leds[LP5523_MAX_LEDS];
 159         struct lp5523_platform_data *pdata;
 160         u8                      num_channels;
 161         u8                      num_leds;
 162 };
 163
 164 static inline void lp5523_wait_opmode_done(void)
 165 {
 166         usleep_range(1000, 2000);
 167 }
 168
 169 static void lp5523_set_led_current(struct lp55xx_led *led, u8 led_current)
 170 {
 171         led->led_current = led_current;
 172         lp55xx_write(led->chip, LP5523_REG_LED_CURRENT_BASE + led->chan_nr,
 173                 led_current);
 174 }
 175
 176 static int lp5523_post_init_device(struct lp55xx_chip *chip)
 177 {
 178         int ret;
 179
 180         ret = lp55xx_write(chip, LP5523_REG_ENABLE, LP5523_ENABLE);
 181         if (ret)
 182                 return ret;
 183
 184         /* Chip startup time is 500 us, 1 - 2 ms gives some margin */
 185         usleep_range(1000, 2000);
 186
 187         ret = lp55xx_write(chip, LP5523_REG_CONFIG,
 188                             LP5523_AUTO_INC | LP5523_PWR_SAVE |
 189                             LP5523_CP_AUTO | LP5523_AUTO_CLK |
 190                             LP5523_PWM_PWR_SAVE);
 191         if (ret)
 192                 return ret;
 193
 194         /* turn on all leds */
 195         ret = lp55xx_write(chip, LP5523_REG_ENABLE_LEDS_MSB, 0x01);
 196         if (ret)
 197                 return ret;
 198
 199         return lp55xx_write(chip, LP5523_REG_ENABLE_LEDS_LSB, 0xff);
 200 }
 201
 202 static void lp5523_load_engine(struct lp55xx_chip *chip)
 203 {
 204         enum lp55xx_engine_index idx = chip->engine_idx;
 205         u8 mask[] = {
 206                 [LP55XX_ENGINE_1] = LP5523_MODE_ENG1_M,
 207                 [LP55XX_ENGINE_2] = LP5523_MODE_ENG2_M,
 208                 [LP55XX_ENGINE_3] = LP5523_MODE_ENG3_M,
 209         };
 210
 211         u8 val[] = {
 212                 [LP55XX_ENGINE_1] = LP5523_LOAD_ENG1,
 213                 [LP55XX_ENGINE_2] = LP5523_LOAD_ENG2,
 214                 [LP55XX_ENGINE_3] = LP5523_LOAD_ENG3,
 215         };
 216
 217         u8 page_sel[] = {
 218                 [LP55XX_ENGINE_1] = LP5523_PAGE_ENG1,
 219                 [LP55XX_ENGINE_2] = LP5523_PAGE_ENG2,
 220                 [LP55XX_ENGINE_3] = LP5523_PAGE_ENG3,
 221         };
 222
 223         lp55xx_update_bits(chip, LP5523_REG_OP_MODE, mask[idx], val[idx]);
 224
 225         lp5523_wait_opmode_done();
 226
 227         lp55xx_write(chip, LP5523_REG_PROG_PAGE_SEL, page_sel[idx]);
 228 }
 229
 230 static void lp5523_stop_engine(struct lp55xx_chip *chip)
 231 {
 232         lp55xx_write(chip, LP5523_REG_OP_MODE, 0);
 233         lp5523_wait_opmode_done();
 234 }
 235
 236 static void lp5523_turn_off_channels(struct lp55xx_chip *chip)
 237 {
 238         int i;
 239
 240         for (i = 0; i < LP5523_MAX_LEDS; i++)
 241                 lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0);
 242 }
 243
 244 static void lp5523_run_engine(struct lp55xx_chip *chip, bool start)
 245 {
 246         int ret;
 247         u8 mode;
 248         u8 exec;
 249
 250         /* stop engine */
 251         if (!start) {
 252                 lp5523_stop_engine(chip);
 253                 lp5523_turn_off_channels(chip);
 254                 return;
 255         }
 256
 257         /*
 258          * To run the engine,
 259          * operation mode and enable register should updated at the same time
 260          */
 261
 262         ret = lp55xx_read(chip, LP5523_REG_OP_MODE, &mode);
 263         if (ret)
 264                 return;
 265
 266         ret = lp55xx_read(chip, LP5523_REG_ENABLE, &exec);
 267         if (ret)
 268                 return;
 269
 270         /* change operation mode to RUN only when each engine is loading */
 271         if (LP5523_ENG1_IS_LOADING(mode)) {
 272                 mode = (mode & ~LP5523_MODE_ENG1_M) | LP5523_RUN_ENG1;
 273                 exec = (exec & ~LP5523_EXEC_ENG1_M) | LP5523_RUN_ENG1;
 274         }
 275
 276         if (LP5523_ENG2_IS_LOADING(mode)) {
 277                 mode = (mode & ~LP5523_MODE_ENG2_M) | LP5523_RUN_ENG2;
 278                 exec = (exec & ~LP5523_EXEC_ENG2_M) | LP5523_RUN_ENG2;
 279         }
 280
 281         if (LP5523_ENG3_IS_LOADING(mode)) {
 282                 mode = (mode & ~LP5523_MODE_ENG3_M) | LP5523_RUN_ENG3;
 283                 exec = (exec & ~LP5523_EXEC_ENG3_M) | LP5523_RUN_ENG3;
 284         }
 285
 286         lp55xx_write(chip, LP5523_REG_OP_MODE, mode);
 287         lp5523_wait_opmode_done();
 288
 289         lp55xx_update_bits(chip, LP5523_REG_ENABLE, LP5523_EXEC_M, exec);
 290 }
 291
 292 static int lp5523_update_program_memory(struct lp55xx_chip *chip,
 293                                         const u8 *data, size_t size)
 294 {
 295         u8 pattern[LP5523_PROGRAM_LENGTH] = {0};
 296         unsigned cmd;
 297         char c[3];
 298         int update_size;
 299         int nrchars;
 300         int offset = 0;
 301         int ret;
 302         int i;
 303
 304         /* clear program memory before updating */
 305         for (i = 0; i < LP5523_PROGRAM_LENGTH; i++)
 306                 lp55xx_write(chip, LP5523_REG_PROG_MEM + i, 0);
 307
 308         i = 0;
 309         while ((offset < size - 1) && (i < LP5523_PROGRAM_LENGTH)) {
 310                 /* separate sscanfs because length is working only for %s */
 311                 ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
 312                 if (ret != 1)
 313                         goto err;
 314
 315                 ret = sscanf(c, "%2x", &cmd);
 316                 if (ret != 1)
 317                         goto err;
 318
 319                 pattern[i] = (u8)cmd;
 320                 offset += nrchars;
 321                 i++;
 322         }
 323
 324         /* Each instruction is 16bit long. Check that length is even */
 325         if (i % 2)
 326                 goto err;
 327
 328         update_size = i;
 329         for (i = 0; i < update_size; i++)
 330                 lp55xx_write(chip, LP5523_REG_PROG_MEM + i, pattern[i]);
 331
 332         return 0;
 333
 334 err:
 335         dev_err(&chip->cl->dev, "wrong pattern format\n");
 336         return -EINVAL;
 337 }
 338
 339 static void lp5523_firmware_loaded(struct lp55xx_chip *chip)
 340 {
 341         const struct firmware *fw = chip->fw;
 342
 343         if (fw->size > LP5523_PROGRAM_LENGTH) {
 344                 dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
 345                         fw->size);
 346                 return;
 347         }
 348
 349         /*
 350          * Program momery sequence
 351          *  1) set engine mode to "LOAD"
 352          *  2) write firmware data into program memory
 353          */
 354
 355         lp5523_load_engine(chip);
 356         lp5523_update_program_memory(chip, fw->data, fw->size);
 357 }
 358
 359 static ssize_t lp5523_selftest(struct device *dev,
 360                                struct device_attribute *attr,
 361                                char *buf)
 362 {
 363         struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
 364         struct lp55xx_chip *chip = led->chip;
 365         struct lp55xx_platform_data *pdata = chip->pdata;
 366         int i, ret, pos = 0;
 367         u8 status, adc, vdd;
 368
 369         mutex_lock(&chip->lock);
 370
 371         ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
 372         if (ret < 0)
 373                 goto fail;
 374
 375         /* Check that ext clock is really in use if requested */
 376         if (pdata->clock_mode == LP55XX_CLOCK_EXT) {
 377                 if  ((status & LP5523_EXT_CLK_USED) == 0)
 378                         goto fail;
 379         }
 380
 381         /* Measure VDD (i.e. VBAT) first (channel 16 corresponds to VDD) */
 382         lp55xx_write(chip, LP5523_REG_LED_TEST_CTRL, LP5523_EN_LEDTEST | 16);
 383         usleep_range(3000, 6000); /* ADC conversion time is typically 2.7 ms */
 384         ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
 385         if (ret < 0)
 386                 goto fail;
 387
 388         if (!(status & LP5523_LEDTEST_DONE))
 389                 usleep_range(3000, 6000); /* Was not ready. Wait little bit */
 390
 391         ret = lp55xx_read(chip, LP5523_REG_LED_TEST_ADC, &vdd);
 392         if (ret < 0)
 393                 goto fail;
 394
 395         vdd--;  /* There may be some fluctuation in measurement */
 396
 397         for (i = 0; i < LP5523_MAX_LEDS; i++) {
 398                 /* Skip non-existing channels */
 399                 if (pdata->led_config[i].led_current == 0)
 400                         continue;
 401
 402                 /* Set default current */
 403                 lp55xx_write(chip, LP5523_REG_LED_CURRENT_BASE + i,
 404                         pdata->led_config[i].led_current);
 405
 406                 lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0xff);
 407                 /* let current stabilize 2 - 4ms before measurements start */
 408                 usleep_range(2000, 4000);
 409                 lp55xx_write(chip, LP5523_REG_LED_TEST_CTRL,
 410                              LP5523_EN_LEDTEST | i);
 411                 /* ADC conversion time is 2.7 ms typically */
 412                 usleep_range(3000, 6000);
 413                 ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
 414                 if (ret < 0)
 415                         goto fail;
 416
 417                 if (!(status & LP5523_LEDTEST_DONE))
 418                         usleep_range(3000, 6000);/* Was not ready. Wait. */
 419
 420                 ret = lp55xx_read(chip, LP5523_REG_LED_TEST_ADC, &adc);
 421                 if (ret < 0)
 422                         goto fail;
 423
 424                 if (adc >= vdd || adc < LP5523_ADC_SHORTCIRC_LIM)
 425                         pos += sprintf(buf + pos, "LED %d FAIL\n", i);
 426
 427                 lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0x00);
 428
 429                 /* Restore current */
 430                 lp55xx_write(chip, LP5523_REG_LED_CURRENT_BASE + i,
 431                         led->led_current);
 432                 led++;
 433         }
 434         if (pos == 0)
 435                 pos = sprintf(buf, "OK\n");
 436         goto release_lock;
 437 fail:
 438         pos = sprintf(buf, "FAIL\n");
 439
 440 release_lock:
 441         mutex_unlock(&chip->lock);
 442
 443         return pos;
 444 }
 445
 446 static void lp5523_led_brightness_work(struct work_struct *work)
 447 {
 448         struct lp55xx_led *led = container_of(work, struct lp55xx_led,
 449                                               brightness_work);
 450         struct lp55xx_chip *chip = led->chip;
 451
 452         mutex_lock(&chip->lock);
 453         lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + led->chan_nr,
 454                      led->brightness);
 455         mutex_unlock(&chip->lock);
 456 }
 457
 458 static DEVICE_ATTR(selftest, S_IRUGO, lp5523_selftest, NULL);
 459
 460 static struct attribute *lp5523_attributes[] = {
 461         &dev_attr_selftest.attr,
 462         NULL,
 463 };
 464
 465 static const struct attribute_group lp5523_group = {
 466         .attrs = lp5523_attributes,
 467 };
 468
 469 /* Chip specific configurations */
 470 static struct lp55xx_device_config lp5523_cfg = {
 471         .reset = {
 472                 .addr = LP5523_REG_RESET,
 473                 .val  = LP5523_RESET,
 474         },
 475         .enable = {
 476                 .addr = LP5523_REG_ENABLE,
 477                 .val  = LP5523_ENABLE,
 478         },
 479         .max_channel  = LP5523_MAX_LEDS,
 480         .post_init_device   = lp5523_post_init_device,
 481         .brightness_work_fn = lp5523_led_brightness_work,
 482         .set_led_current    = lp5523_set_led_current,
 483         .firmware_cb        = lp5523_firmware_loaded,
 484         .run_engine         = lp5523_run_engine,
 485         .dev_attr_group     = &lp5523_group,
 486 };
 487
 488 static int lp5523_probe(struct i2c_client *client,
 489                         const struct i2c_device_id *id)
 490 {
 491         int ret;
 492         struct lp55xx_chip *chip;
 493         struct lp55xx_led *led;
 494         struct lp55xx_platform_data *pdata = client->dev.platform_data;
 495
 496         if (!pdata) {
 497                 dev_err(&client->dev, "no platform data\n");
 498                 return -EINVAL;
 499         }
 500
 501         chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
 502         if (!chip)
 503                 return -ENOMEM;
 504
 505         led = devm_kzalloc(&client->dev,
 506                         sizeof(*led) * pdata->num_channels, GFP_KERNEL);
 507         if (!led)
 508                 return -ENOMEM;
 509
 510         chip->cl = client;
 511         chip->pdata = pdata;
 512         chip->cfg = &lp5523_cfg;
 513
 514         mutex_init(&chip->lock);
 515
 516         i2c_set_clientdata(client, led);
 517
 518         ret = lp55xx_init_device(chip);
 519         if (ret)
 520                 goto err_init;
 521
 522         dev_info(&client->dev, "%s Programmable led chip found\n", id->name);
 523
 524         ret = lp55xx_register_leds(led, chip);
 525         if (ret)
 526                 goto err_register_leds;
 527
 528         ret = lp55xx_register_sysfs(chip);
 529         if (ret) {
 530                 dev_err(&client->dev, "registering sysfs failed\n");
 531                 goto err_register_sysfs;
 532         }
 533
 534         return 0;
 535
 536 err_register_sysfs:
 537         lp55xx_unregister_leds(led, chip);
 538 err_register_leds:
 539         lp55xx_deinit_device(chip);
 540 err_init:
 541         return ret;
 542 }
 543
 544 static int lp5523_remove(struct i2c_client *client)
 545 {
 546         struct lp55xx_led *led = i2c_get_clientdata(client);
 547         struct lp55xx_chip *chip = led->chip;
 548
 549         lp5523_stop_engine(chip);
 550         lp55xx_unregister_sysfs(chip);
 551         lp55xx_unregister_leds(led, chip);
 552         lp55xx_deinit_device(chip);
 553
 554         return 0;
 555 }
 556
 557 static const struct i2c_device_id lp5523_id[] = {
 558         { "lp5523",  LP5523 },
 559         { "lp55231", LP55231 },
 560         { }
 561 };
 562
 563 MODULE_DEVICE_TABLE(i2c, lp5523_id);
 564
 565 static struct i2c_driver lp5523_driver = {
 566         .driver = {
 567                 .name   = "lp5523x",
 568         },
 569         .probe          = lp5523_probe,
 570         .remove         = lp5523_remove,
 571         .id_table       = lp5523_id,
 572 };
 573
 574 module_i2c_driver(lp5523_driver);
 575
 576 MODULE_AUTHOR("Mathias Nyman <mathias.nyman@nokia.com>");
 577 MODULE_DESCRIPTION("LP5523 LED engine");
 578 MODULE_LICENSE("GPL");