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
  38 #define LP5523_REG_ENABLE               0x00
  39 #define LP5523_REG_OP_MODE              0x01
  40 #define LP5523_REG_RATIOMETRIC_MSB      0x02
  41 #define LP5523_REG_RATIOMETRIC_LSB      0x03
  42 #define LP5523_REG_ENABLE_LEDS_MSB      0x04
  43 #define LP5523_REG_ENABLE_LEDS_LSB      0x05
  44 #define LP5523_REG_LED_CNTRL_BASE       0x06
  45 #define LP5523_REG_LED_PWM_BASE         0x16
  46 #define LP5523_REG_LED_CURRENT_BASE     0x26
  47 #define LP5523_REG_CONFIG               0x36
  48 #define LP5523_REG_CHANNEL1_PC          0x37
  49 #define LP5523_REG_CHANNEL2_PC          0x38
  50 #define LP5523_REG_CHANNEL3_PC          0x39
  51 #define LP5523_REG_STATUS               0x3a
  52 #define LP5523_REG_GPO                  0x3b
  53 #define LP5523_REG_VARIABLE             0x3c
  54 #define LP5523_REG_RESET                0x3d
  55 #define LP5523_REG_TEMP_CTRL            0x3e
  56 #define LP5523_REG_TEMP_READ            0x3f
  57 #define LP5523_REG_TEMP_WRITE           0x40
  58 #define LP5523_REG_LED_TEST_CTRL        0x41
  59 #define LP5523_REG_LED_TEST_ADC         0x42
  60 #define LP5523_REG_ENG1_VARIABLE        0x45
  61 #define LP5523_REG_ENG2_VARIABLE        0x46
  62 #define LP5523_REG_ENG3_VARIABLE        0x47
  63 #define LP5523_REG_MASTER_FADER1        0x48
  64 #define LP5523_REG_MASTER_FADER2        0x49
  65 #define LP5523_REG_MASTER_FADER3        0x4a
  66 #define LP5523_REG_CH1_PROG_START       0x4c
  67 #define LP5523_REG_CH2_PROG_START       0x4d
  68 #define LP5523_REG_CH3_PROG_START       0x4e
  69 #define LP5523_REG_PROG_PAGE_SEL        0x4f
  70 #define LP5523_REG_PROG_MEM             0x50
  71
  72 #define LP5523_CMD_LOAD                 0x15 /* 00010101 */
  73 #define LP5523_CMD_RUN                  0x2a /* 00101010 */
  74 #define LP5523_CMD_DISABLED             0x00 /* 00000000 */
  75
  76 #define LP5523_ENABLE                   0x40
  77 #define LP5523_AUTO_INC                 0x40
  78 #define LP5523_PWR_SAVE                 0x20
  79 #define LP5523_PWM_PWR_SAVE             0x04
  80 #define LP5523_CP_1                     0x08
  81 #define LP5523_CP_1_5                   0x10
  82 #define LP5523_CP_AUTO                  0x18
  83 #define LP5523_INT_CLK                  0x01
  84 #define LP5523_AUTO_CLK                 0x02
  85 #define LP5523_EN_LEDTEST               0x80
  86 #define LP5523_LEDTEST_DONE             0x80
  87
  88 #define LP5523_DEFAULT_CURRENT          50 /* microAmps */
  89 #define LP5523_PROGRAM_LENGTH           32 /* in bytes */
  90 #define LP5523_PROGRAM_PAGES            6
  91 #define LP5523_ADC_SHORTCIRC_LIM        80
  92
  93 #define LP5523_LEDS                     9
  94 #define LP5523_ENGINES                  3
  95
  96 #define LP5523_ENG_MASK_BASE            0x30 /* 00110000 */
  97
  98 #define LP5523_ENG_STATUS_MASK          0x07 /* 00000111 */
  99
 100 #define LP5523_IRQ_FLAGS                IRQF_TRIGGER_FALLING
 101
 102 #define LP5523_EXT_CLK_USED             0x08
 103
 104 #define LED_ACTIVE(mux, led)            (!!(mux & (0x0001 << led)))
 105 #define SHIFT_MASK(id)                  (((id) - 1) * 2)
 106
 107 struct lp5523_engine {
 108         const struct attribute_group *attributes;
 109         int             id;
 110         u8              mode;
 111         u8              prog_page;
 112         u8              mux_page;
 113         u16             led_mux;
 114         u8              engine_mask;
 115 };
 116
 117 struct lp5523_led {
 118         int                     id;
 119         u8                      chan_nr;
 120         u8                      led_current;
 121         u8                      max_current;
 122         struct led_classdev     cdev;
 123         struct work_struct      brightness_work;
 124         u8                      brightness;
 125 };
 126
 127 struct lp5523_chip {
 128         struct mutex            lock; /* Serialize control */
 129         struct i2c_client       *client;
 130         struct lp5523_engine    engines[LP5523_ENGINES];
 131         struct lp5523_led       leds[LP5523_LEDS];
 132         struct lp5523_platform_data *pdata;
 133         u8                      num_channels;
 134         u8                      num_leds;
 135 };
 136
 137 static inline struct lp5523_led *cdev_to_led(struct led_classdev *cdev)
 138 {
 139         return container_of(cdev, struct lp5523_led, cdev);
 140 }
 141
 142 static inline struct lp5523_chip *engine_to_lp5523(struct lp5523_engine *engine)
 143 {
 144         return container_of(engine, struct lp5523_chip,
 145                             engines[engine->id - 1]);
 146 }
 147
 148 static inline struct lp5523_chip *led_to_lp5523(struct lp5523_led *led)
 149 {
 150         return container_of(led, struct lp5523_chip,
 151                             leds[led->id]);
 152 }
 153
 154 static int lp5523_set_mode(struct lp5523_engine *engine, u8 mode);
 155 static int lp5523_set_engine_mode(struct lp5523_engine *engine, u8 mode);
 156 static int lp5523_load_program(struct lp5523_engine *engine, u8 *pattern);
 157
 158 static void lp5523_led_brightness_work(struct work_struct *work);
 159
 160 static int lp5523_write(struct i2c_client *client, u8 reg, u8 value)
 161 {
 162         return i2c_smbus_write_byte_data(client, reg, value);
 163 }
 164
 165 static int lp5523_read(struct i2c_client *client, u8 reg, u8 *buf)
 166 {
 167         s32 ret = i2c_smbus_read_byte_data(client, reg);
 168
 169         if (ret < 0)
 170                 return -EIO;
 171
 172         *buf = ret;
 173         return 0;
 174 }
 175
 176 static int lp5523_detect(struct i2c_client *client)
 177 {
 178         int ret;
 179         u8 buf;
 180
 181         ret = lp5523_write(client, LP5523_REG_ENABLE, 0x40);
 182         if (ret)
 183                 return ret;
 184         ret = lp5523_read(client, LP5523_REG_ENABLE, &buf);
 185         if (ret)
 186                 return ret;
 187         if (buf == 0x40)
 188                 return 0;
 189         else
 190                 return -ENODEV;
 191 }
 192
 193 static int lp5523_configure(struct i2c_client *client)
 194 {
 195         struct lp5523_chip *chip = i2c_get_clientdata(client);
 196         int ret = 0;
 197         u8 status;
 198
 199         /* one pattern per engine setting led mux start and stop addresses */
 200         u8 pattern[][LP5523_PROGRAM_LENGTH] =  {
 201                 { 0x9c, 0x30, 0x9c, 0xb0, 0x9d, 0x80, 0xd8, 0x00, 0},
 202                 { 0x9c, 0x40, 0x9c, 0xc0, 0x9d, 0x80, 0xd8, 0x00, 0},
 203                 { 0x9c, 0x50, 0x9c, 0xd0, 0x9d, 0x80, 0xd8, 0x00, 0},
 204         };
 205
 206         ret |= lp5523_write(client, LP5523_REG_ENABLE, LP5523_ENABLE);
 207         /* Chip startup time is 500 us, 1 - 2 ms gives some margin */
 208         usleep_range(1000, 2000);
 209
 210         ret |= lp5523_write(client, LP5523_REG_CONFIG,
 211                             LP5523_AUTO_INC | LP5523_PWR_SAVE |
 212                             LP5523_CP_AUTO | LP5523_AUTO_CLK |
 213                             LP5523_PWM_PWR_SAVE);
 214
 215         /* turn on all leds */
 216         ret |= lp5523_write(client, LP5523_REG_ENABLE_LEDS_MSB, 0x01);
 217         ret |= lp5523_write(client, LP5523_REG_ENABLE_LEDS_LSB, 0xff);
 218
 219         /* hardcode 32 bytes of memory for each engine from program memory */
 220         ret |= lp5523_write(client, LP5523_REG_CH1_PROG_START, 0x00);
 221         ret |= lp5523_write(client, LP5523_REG_CH2_PROG_START, 0x10);
 222         ret |= lp5523_write(client, LP5523_REG_CH3_PROG_START, 0x20);
 223
 224         /* write led mux address space for each channel */
 225         ret |= lp5523_load_program(&chip->engines[0], pattern[0]);
 226         ret |= lp5523_load_program(&chip->engines[1], pattern[1]);
 227         ret |= lp5523_load_program(&chip->engines[2], pattern[2]);
 228
 229         if (ret) {
 230                 dev_err(&client->dev, "could not load mux programs\n");
 231                 return -1;
 232         }
 233
 234         /* set all engines exec state and mode to run 00101010 */
 235         ret |= lp5523_write(client, LP5523_REG_ENABLE,
 236                             (LP5523_CMD_RUN | LP5523_ENABLE));
 237
 238         ret |= lp5523_write(client, LP5523_REG_OP_MODE, LP5523_CMD_RUN);
 239
 240         if (ret) {
 241                 dev_err(&client->dev, "could not start mux programs\n");
 242                 return -1;
 243         }
 244
 245         /* Let the programs run for couple of ms and check the engine status */
 246         usleep_range(3000, 6000);
 247         lp5523_read(client, LP5523_REG_STATUS, &status);
 248         status &= LP5523_ENG_STATUS_MASK;
 249
 250         if (status == LP5523_ENG_STATUS_MASK) {
 251                 dev_dbg(&client->dev, "all engines configured\n");
 252         } else {
 253                 dev_info(&client->dev, "status == %x\n", status);
 254                 dev_err(&client->dev, "cound not configure LED engine\n");
 255                 return -1;
 256         }
 257
 258         dev_info(&client->dev, "disabling engines\n");
 259
 260         ret |= lp5523_write(client, LP5523_REG_OP_MODE, LP5523_CMD_DISABLED);
 261
 262         return ret;
 263 }
 264
 265 static int lp5523_set_engine_mode(struct lp5523_engine *engine, u8 mode)
 266 {
 267         struct lp5523_chip *chip = engine_to_lp5523(engine);
 268         struct i2c_client *client = chip->client;
 269         int ret;
 270         u8 engine_state;
 271
 272         ret = lp5523_read(client, LP5523_REG_OP_MODE, &engine_state);
 273         if (ret)
 274                 goto fail;
 275
 276         engine_state &= ~(engine->engine_mask);
 277
 278         /* set mode only for this engine */
 279         mode &= engine->engine_mask;
 280
 281         engine_state |= mode;
 282
 283         ret |= lp5523_write(client, LP5523_REG_OP_MODE, engine_state);
 284 fail:
 285         return ret;
 286 }
 287
 288 static int lp5523_load_mux(struct lp5523_engine *engine, u16 mux)
 289 {
 290         struct lp5523_chip *chip = engine_to_lp5523(engine);
 291         struct i2c_client *client = chip->client;
 292         int ret = 0;
 293
 294         ret |= lp5523_set_engine_mode(engine, LP5523_CMD_LOAD);
 295
 296         ret |= lp5523_write(client, LP5523_REG_PROG_PAGE_SEL, engine->mux_page);
 297         ret |= lp5523_write(client, LP5523_REG_PROG_MEM,
 298                             (u8)(mux >> 8));
 299         ret |= lp5523_write(client, LP5523_REG_PROG_MEM + 1, (u8)(mux));
 300         engine->led_mux = mux;
 301
 302         return ret;
 303 }
 304
 305 static int lp5523_load_program(struct lp5523_engine *engine, u8 *pattern)
 306 {
 307         struct lp5523_chip *chip = engine_to_lp5523(engine);
 308         struct i2c_client *client = chip->client;
 309
 310         int ret = 0;
 311
 312         ret |= lp5523_set_engine_mode(engine, LP5523_CMD_LOAD);
 313
 314         ret |= lp5523_write(client, LP5523_REG_PROG_PAGE_SEL,
 315                             engine->prog_page);
 316         ret |= i2c_smbus_write_i2c_block_data(client, LP5523_REG_PROG_MEM,
 317                                               LP5523_PROGRAM_LENGTH, pattern);
 318
 319         return ret;
 320 }
 321
 322 static int lp5523_run_program(struct lp5523_engine *engine)
 323 {
 324         struct lp5523_chip *chip = engine_to_lp5523(engine);
 325         struct i2c_client *client = chip->client;
 326         int ret;
 327
 328         ret = lp5523_write(client, LP5523_REG_ENABLE,
 329                                         LP5523_CMD_RUN | LP5523_ENABLE);
 330         if (ret)
 331                 goto fail;
 332
 333         ret = lp5523_set_engine_mode(engine, LP5523_CMD_RUN);
 334 fail:
 335         return ret;
 336 }
 337
 338 static int lp5523_mux_parse(const char *buf, u16 *mux, size_t len)
 339 {
 340         int i;
 341         u16 tmp_mux = 0;
 342         len = len < LP5523_LEDS ? len : LP5523_LEDS;
 343         for (i = 0; i < len; i++) {
 344                 switch (buf[i]) {
 345                 case '1':
 346                         tmp_mux |= (1 << i);
 347                         break;
 348                 case '0':
 349                         break;
 350                 case '\n':
 351                         i = len;
 352                         break;
 353                 default:
 354                         return -1;
 355                 }
 356         }
 357         *mux = tmp_mux;
 358
 359         return 0;
 360 }
 361
 362 static void lp5523_mux_to_array(u16 led_mux, char *array)
 363 {
 364         int i, pos = 0;
 365         for (i = 0; i < LP5523_LEDS; i++)
 366                 pos += sprintf(array + pos, "%x", LED_ACTIVE(led_mux, i));
 367
 368         array[pos] = '\0';
 369 }
 370
 371 /*--------------------------------------------------------------*/
 372 /*                      Sysfs interface                         */
 373 /*--------------------------------------------------------------*/
 374
 375 static ssize_t show_engine_leds(struct device *dev,
 376                             struct device_attribute *attr,
 377                             char *buf, int nr)
 378 {
 379         struct i2c_client *client = to_i2c_client(dev);
 380         struct lp5523_chip *chip = i2c_get_clientdata(client);
 381         char mux[LP5523_LEDS + 1];
 382
 383         lp5523_mux_to_array(chip->engines[nr - 1].led_mux, mux);
 384
 385         return sprintf(buf, "%s\n", mux);
 386 }
 387
 388 #define show_leds(nr)                                                   \
 389 static ssize_t show_engine##nr##_leds(struct device *dev,               \
 390                             struct device_attribute *attr,              \
 391                             char *buf)                                  \
 392 {                                                                       \
 393         return show_engine_leds(dev, attr, buf, nr);                    \
 394 }
 395 show_leds(1)
 396 show_leds(2)
 397 show_leds(3)
 398
 399 static ssize_t store_engine_leds(struct device *dev,
 400                              struct device_attribute *attr,
 401                              const char *buf, size_t len, int nr)
 402 {
 403         struct i2c_client *client = to_i2c_client(dev);
 404         struct lp5523_chip *chip = i2c_get_clientdata(client);
 405         u16 mux = 0;
 406
 407         if (lp5523_mux_parse(buf, &mux, len))
 408                 return -EINVAL;
 409
 410         if (lp5523_load_mux(&chip->engines[nr - 1], mux))
 411                 return -EINVAL;
 412
 413         return len;
 414 }
 415
 416 #define store_leds(nr)                                          \
 417 static ssize_t store_engine##nr##_leds(struct device *dev,      \
 418                              struct device_attribute *attr,     \
 419                              const char *buf, size_t len)       \
 420 {                                                               \
 421         return store_engine_leds(dev, attr, buf, len, nr);      \
 422 }
 423 store_leds(1)
 424 store_leds(2)
 425 store_leds(3)
 426
 427 static ssize_t lp5523_selftest(struct device *dev,
 428                                struct device_attribute *attr,
 429                                char *buf)
 430 {
 431         struct i2c_client *client = to_i2c_client(dev);
 432         struct lp5523_chip *chip = i2c_get_clientdata(client);
 433         int i, ret, pos = 0;
 434         int led = 0;
 435         u8 status, adc, vdd;
 436
 437         mutex_lock(&chip->lock);
 438
 439         ret = lp5523_read(chip->client, LP5523_REG_STATUS, &status);
 440         if (ret < 0)
 441                 goto fail;
 442
 443         /* Check that ext clock is really in use if requested */
 444         if ((chip->pdata) && (chip->pdata->clock_mode == LP5523_CLOCK_EXT))
 445                 if  ((status & LP5523_EXT_CLK_USED) == 0)
 446                         goto fail;
 447
 448         /* Measure VDD (i.e. VBAT) first (channel 16 corresponds to VDD) */
 449         lp5523_write(chip->client, LP5523_REG_LED_TEST_CTRL,
 450                                     LP5523_EN_LEDTEST | 16);
 451         usleep_range(3000, 6000); /* ADC conversion time is typically 2.7 ms */
 452         ret = lp5523_read(chip->client, LP5523_REG_STATUS, &status);
 453         if (!(status & LP5523_LEDTEST_DONE))
 454                 usleep_range(3000, 6000); /* Was not ready. Wait little bit */
 455
 456         ret |= lp5523_read(chip->client, LP5523_REG_LED_TEST_ADC, &vdd);
 457         vdd--;  /* There may be some fluctuation in measurement */
 458
 459         for (i = 0; i < LP5523_LEDS; i++) {
 460                 /* Skip non-existing channels */
 461                 if (chip->pdata->led_config[i].led_current == 0)
 462                         continue;
 463
 464                 /* Set default current */
 465                 lp5523_write(chip->client,
 466                         LP5523_REG_LED_CURRENT_BASE + i,
 467                         chip->pdata->led_config[i].led_current);
 468
 469                 lp5523_write(chip->client, LP5523_REG_LED_PWM_BASE + i, 0xff);
 470                 /* let current stabilize 2 - 4ms before measurements start */
 471                 usleep_range(2000, 4000);
 472                 lp5523_write(chip->client,
 473                              LP5523_REG_LED_TEST_CTRL,
 474                              LP5523_EN_LEDTEST | i);
 475                 /* ADC conversion time is 2.7 ms typically */
 476                 usleep_range(3000, 6000);
 477                 ret = lp5523_read(chip->client, LP5523_REG_STATUS, &status);
 478                 if (!(status & LP5523_LEDTEST_DONE))
 479                         usleep_range(3000, 6000);/* Was not ready. Wait. */
 480                 ret |= lp5523_read(chip->client, LP5523_REG_LED_TEST_ADC, &adc);
 481
 482                 if (adc >= vdd || adc < LP5523_ADC_SHORTCIRC_LIM)
 483                         pos += sprintf(buf + pos, "LED %d FAIL\n", i);
 484
 485                 lp5523_write(chip->client, LP5523_REG_LED_PWM_BASE + i, 0x00);
 486
 487                 /* Restore current */
 488                 lp5523_write(chip->client,
 489                         LP5523_REG_LED_CURRENT_BASE + i,
 490                         chip->leds[led].led_current);
 491                 led++;
 492         }
 493         if (pos == 0)
 494                 pos = sprintf(buf, "OK\n");
 495         goto release_lock;
 496 fail:
 497         pos = sprintf(buf, "FAIL\n");
 498
 499 release_lock:
 500         mutex_unlock(&chip->lock);
 501
 502         return pos;
 503 }
 504
 505 static void lp5523_set_brightness(struct led_classdev *cdev,
 506                              enum led_brightness brightness)
 507 {
 508         struct lp5523_led *led = cdev_to_led(cdev);
 509
 510         led->brightness = (u8)brightness;
 511
 512         schedule_work(&led->brightness_work);
 513 }
 514
 515 static void lp5523_led_brightness_work(struct work_struct *work)
 516 {
 517         struct lp5523_led *led = container_of(work,
 518                                               struct lp5523_led,
 519                                               brightness_work);
 520         struct lp5523_chip *chip = led_to_lp5523(led);
 521         struct i2c_client *client = chip->client;
 522
 523         mutex_lock(&chip->lock);
 524
 525         lp5523_write(client, LP5523_REG_LED_PWM_BASE + led->chan_nr,
 526                      led->brightness);
 527
 528         mutex_unlock(&chip->lock);
 529 }
 530
 531 static int lp5523_do_store_load(struct lp5523_engine *engine,
 532                                 const char *buf, size_t len)
 533 {
 534         struct lp5523_chip *chip = engine_to_lp5523(engine);
 535         struct i2c_client *client = chip->client;
 536         int  ret, nrchars, offset = 0, i = 0;
 537         char c[3];
 538         unsigned cmd;
 539         u8 pattern[LP5523_PROGRAM_LENGTH] = {0};
 540
 541         while ((offset < len - 1) && (i < LP5523_PROGRAM_LENGTH)) {
 542                 /* separate sscanfs because length is working only for %s */
 543                 ret = sscanf(buf + offset, "%2s%n ", c, &nrchars);
 544                 ret = sscanf(c, "%2x", &cmd);
 545                 if (ret != 1)
 546                         goto fail;
 547                 pattern[i] = (u8)cmd;
 548
 549                 offset += nrchars;
 550                 i++;
 551         }
 552
 553         /* Each instruction is 16bit long. Check that length is even */
 554         if (i % 2)
 555                 goto fail;
 556
 557         mutex_lock(&chip->lock);
 558
 559         ret = lp5523_load_program(engine, pattern);
 560         mutex_unlock(&chip->lock);
 561
 562         if (ret) {
 563                 dev_err(&client->dev, "failed loading pattern\n");
 564                 return ret;
 565         }
 566
 567         return len;
 568 fail:
 569         dev_err(&client->dev, "wrong pattern format\n");
 570         return -EINVAL;
 571 }
 572
 573 static ssize_t store_engine_load(struct device *dev,
 574                                      struct device_attribute *attr,
 575                                      const char *buf, size_t len, int nr)
 576 {
 577         struct i2c_client *client = to_i2c_client(dev);
 578         struct lp5523_chip *chip = i2c_get_clientdata(client);
 579         return lp5523_do_store_load(&chip->engines[nr - 1], buf, len);
 580 }
 581
 582 #define store_load(nr)                                                  \
 583 static ssize_t store_engine##nr##_load(struct device *dev,              \
 584                                      struct device_attribute *attr,     \
 585                                      const char *buf, size_t len)       \
 586 {                                                                       \
 587         return store_engine_load(dev, attr, buf, len, nr);              \
 588 }
 589 store_load(1)
 590 store_load(2)
 591 store_load(3)
 592
 593 static ssize_t show_engine_mode(struct device *dev,
 594                                 struct device_attribute *attr,
 595                                 char *buf, int nr)
 596 {
 597         struct i2c_client *client = to_i2c_client(dev);
 598         struct lp5523_chip *chip = i2c_get_clientdata(client);
 599         switch (chip->engines[nr - 1].mode) {
 600         case LP5523_CMD_RUN:
 601                 return sprintf(buf, "run\n");
 602         case LP5523_CMD_LOAD:
 603                 return sprintf(buf, "load\n");
 604         case LP5523_CMD_DISABLED:
 605                 return sprintf(buf, "disabled\n");
 606         default:
 607                 return sprintf(buf, "disabled\n");
 608         }
 609 }
 610
 611 #define show_mode(nr)                                                   \
 612 static ssize_t show_engine##nr##_mode(struct device *dev,               \
 613                                     struct device_attribute *attr,      \
 614                                     char *buf)                          \
 615 {                                                                       \
 616         return show_engine_mode(dev, attr, buf, nr);                    \
 617 }
 618 show_mode(1)
 619 show_mode(2)
 620 show_mode(3)
 621
 622 static ssize_t store_engine_mode(struct device *dev,
 623                                  struct device_attribute *attr,
 624                                  const char *buf, size_t len, int nr)
 625 {
 626         struct i2c_client *client = to_i2c_client(dev);
 627         struct lp5523_chip *chip = i2c_get_clientdata(client);
 628         struct lp5523_engine *engine = &chip->engines[nr - 1];
 629         mutex_lock(&chip->lock);
 630
 631         if (!strncmp(buf, "run", 3))
 632                 lp5523_set_mode(engine, LP5523_CMD_RUN);
 633         else if (!strncmp(buf, "load", 4))
 634                 lp5523_set_mode(engine, LP5523_CMD_LOAD);
 635         else if (!strncmp(buf, "disabled", 8))
 636                 lp5523_set_mode(engine, LP5523_CMD_DISABLED);
 637
 638         mutex_unlock(&chip->lock);
 639         return len;
 640 }
 641
 642 #define store_mode(nr)                                                  \
 643 static ssize_t store_engine##nr##_mode(struct device *dev,              \
 644                                      struct device_attribute *attr,     \
 645                                      const char *buf, size_t len)       \
 646 {                                                                       \
 647         return store_engine_mode(dev, attr, buf, len, nr);              \
 648 }
 649 store_mode(1)
 650 store_mode(2)
 651 store_mode(3)
 652
 653 static ssize_t show_max_current(struct device *dev,
 654                             struct device_attribute *attr,
 655                             char *buf)
 656 {
 657         struct led_classdev *led_cdev = dev_get_drvdata(dev);
 658         struct lp5523_led *led = cdev_to_led(led_cdev);
 659
 660         return sprintf(buf, "%d\n", led->max_current);
 661 }
 662
 663 static ssize_t show_current(struct device *dev,
 664                             struct device_attribute *attr,
 665                             char *buf)
 666 {
 667         struct led_classdev *led_cdev = dev_get_drvdata(dev);
 668         struct lp5523_led *led = cdev_to_led(led_cdev);
 669
 670         return sprintf(buf, "%d\n", led->led_current);
 671 }
 672
 673 static ssize_t store_current(struct device *dev,
 674                              struct device_attribute *attr,
 675                              const char *buf, size_t len)
 676 {
 677         struct led_classdev *led_cdev = dev_get_drvdata(dev);
 678         struct lp5523_led *led = cdev_to_led(led_cdev);
 679         struct lp5523_chip *chip = led_to_lp5523(led);
 680         ssize_t ret;
 681         unsigned long curr;
 682
 683         if (strict_strtoul(buf, 0, &curr))
 684                 return -EINVAL;
 685
 686         if (curr > led->max_current)
 687                 return -EINVAL;
 688
 689         mutex_lock(&chip->lock);
 690         ret = lp5523_write(chip->client,
 691                         LP5523_REG_LED_CURRENT_BASE + led->chan_nr,
 692                         (u8)curr);
 693         mutex_unlock(&chip->lock);
 694
 695         if (ret < 0)
 696                 return ret;
 697
 698         led->led_current = (u8)curr;
 699
 700         return len;
 701 }
 702
 703 /* led class device attributes */
 704 static DEVICE_ATTR(led_current, S_IRUGO | S_IWUGO, show_current, store_current);
 705 static DEVICE_ATTR(max_current, S_IRUGO , show_max_current, NULL);
 706
 707 static struct attribute *lp5523_led_attributes[] = {
 708         &dev_attr_led_current.attr,
 709         &dev_attr_max_current.attr,
 710         NULL,
 711 };
 712
 713 static struct attribute_group lp5523_led_attribute_group = {
 714         .attrs = lp5523_led_attributes
 715 };
 716
 717 /* device attributes */
 718 static DEVICE_ATTR(engine1_mode, S_IRUGO | S_IWUGO,
 719                    show_engine1_mode, store_engine1_mode);
 720 static DEVICE_ATTR(engine2_mode, S_IRUGO | S_IWUGO,
 721                    show_engine2_mode, store_engine2_mode);
 722 static DEVICE_ATTR(engine3_mode, S_IRUGO | S_IWUGO,
 723                    show_engine3_mode, store_engine3_mode);
 724 static DEVICE_ATTR(engine1_leds, S_IRUGO | S_IWUGO,
 725                    show_engine1_leds, store_engine1_leds);
 726 static DEVICE_ATTR(engine2_leds, S_IRUGO | S_IWUGO,
 727                    show_engine2_leds, store_engine2_leds);
 728 static DEVICE_ATTR(engine3_leds, S_IRUGO | S_IWUGO,
 729                    show_engine3_leds, store_engine3_leds);
 730 static DEVICE_ATTR(engine1_load, S_IWUGO, NULL, store_engine1_load);
 731 static DEVICE_ATTR(engine2_load, S_IWUGO, NULL, store_engine2_load);
 732 static DEVICE_ATTR(engine3_load, S_IWUGO, NULL, store_engine3_load);
 733 static DEVICE_ATTR(selftest, S_IRUGO, lp5523_selftest, NULL);
 734
 735 static struct attribute *lp5523_attributes[] = {
 736         &dev_attr_engine1_mode.attr,
 737         &dev_attr_engine2_mode.attr,
 738         &dev_attr_engine3_mode.attr,
 739         &dev_attr_selftest.attr,
 740         NULL
 741 };
 742
 743 static struct attribute *lp5523_engine1_attributes[] = {
 744         &dev_attr_engine1_load.attr,
 745         &dev_attr_engine1_leds.attr,
 746         NULL
 747 };
 748
 749 static struct attribute *lp5523_engine2_attributes[] = {
 750         &dev_attr_engine2_load.attr,
 751         &dev_attr_engine2_leds.attr,
 752         NULL
 753 };
 754
 755 static struct attribute *lp5523_engine3_attributes[] = {
 756         &dev_attr_engine3_load.attr,
 757         &dev_attr_engine3_leds.attr,
 758         NULL
 759 };
 760
 761 static const struct attribute_group lp5523_group = {
 762         .attrs = lp5523_attributes,
 763 };
 764
 765 static const struct attribute_group lp5523_engine_group[] = {
 766         {.attrs = lp5523_engine1_attributes },
 767         {.attrs = lp5523_engine2_attributes },
 768         {.attrs = lp5523_engine3_attributes },
 769 };
 770
 771 static int lp5523_register_sysfs(struct i2c_client *client)
 772 {
 773         struct device *dev = &client->dev;
 774         int ret;
 775
 776         ret = sysfs_create_group(&dev->kobj, &lp5523_group);
 777         if (ret < 0)
 778                 return ret;
 779
 780         return 0;
 781 }
 782
 783 static void lp5523_unregister_sysfs(struct i2c_client *client)
 784 {
 785         struct lp5523_chip *chip = i2c_get_clientdata(client);
 786         struct device *dev = &client->dev;
 787         int i;
 788
 789         sysfs_remove_group(&dev->kobj, &lp5523_group);
 790
 791         for (i = 0; i < ARRAY_SIZE(chip->engines); i++)
 792                 if (chip->engines[i].mode == LP5523_CMD_LOAD)
 793                         sysfs_remove_group(&dev->kobj, &lp5523_engine_group[i]);
 794
 795         for (i = 0; i < chip->num_leds; i++)
 796                 sysfs_remove_group(&chip->leds[i].cdev.dev->kobj,
 797                                 &lp5523_led_attribute_group);
 798 }
 799
 800 /*--------------------------------------------------------------*/
 801 /*                      Set chip operating mode                 */
 802 /*--------------------------------------------------------------*/
 803 static int lp5523_set_mode(struct lp5523_engine *engine, u8 mode)
 804 {
 805         /*  engine to chip */
 806         struct lp5523_chip *chip = engine_to_lp5523(engine);
 807         struct i2c_client *client = chip->client;
 808         struct device *dev = &client->dev;
 809         int ret = 0;
 810
 811         /* if in that mode already do nothing, except for run */
 812         if (mode == engine->mode && mode != LP5523_CMD_RUN)
 813                 return 0;
 814
 815         if (mode == LP5523_CMD_RUN) {
 816                 ret = lp5523_run_program(engine);
 817         } else if (mode == LP5523_CMD_LOAD) {
 818                 lp5523_set_engine_mode(engine, LP5523_CMD_DISABLED);
 819                 lp5523_set_engine_mode(engine, LP5523_CMD_LOAD);
 820
 821                 ret = sysfs_create_group(&dev->kobj, engine->attributes);
 822                 if (ret)
 823                         return ret;
 824         } else if (mode == LP5523_CMD_DISABLED) {
 825                 lp5523_set_engine_mode(engine, LP5523_CMD_DISABLED);
 826         }
 827
 828         /* remove load attribute from sysfs if not in load mode */
 829         if (engine->mode == LP5523_CMD_LOAD && mode != LP5523_CMD_LOAD)
 830                 sysfs_remove_group(&dev->kobj, engine->attributes);
 831
 832         engine->mode = mode;
 833
 834         return ret;
 835 }
 836
 837 /*--------------------------------------------------------------*/
 838 /*                      Probe, Attach, Remove                   */
 839 /*--------------------------------------------------------------*/
 840 static int __init lp5523_init_engine(struct lp5523_engine *engine, int id)
 841 {
 842         if (id < 1 || id > LP5523_ENGINES)
 843                 return -1;
 844         engine->id = id;
 845         engine->engine_mask = LP5523_ENG_MASK_BASE >> SHIFT_MASK(id);
 846         engine->prog_page = id - 1;
 847         engine->mux_page = id + 2;
 848         engine->attributes = &lp5523_engine_group[id - 1];
 849
 850         return 0;
 851 }
 852
 853 static int __init lp5523_init_led(struct lp5523_led *led, struct device *dev,
 854                            int chan, struct lp5523_platform_data *pdata)
 855 {
 856         char name[32];
 857         int res;
 858
 859         if (chan >= LP5523_LEDS)
 860                 return -EINVAL;
 861
 862         if (pdata->led_config[chan].led_current) {
 863                 led->led_current = pdata->led_config[chan].led_current;
 864                 led->max_current = pdata->led_config[chan].max_current;
 865                 led->chan_nr = pdata->led_config[chan].chan_nr;
 866
 867                 if (led->chan_nr >= LP5523_LEDS) {
 868                         dev_err(dev, "Use channel numbers between 0 and %d\n",
 869                                 LP5523_LEDS - 1);
 870                         return -EINVAL;
 871                 }
 872
 873                 snprintf(name, 32, "lp5523:channel%d", chan);
 874
 875                 led->cdev.name = name;
 876                 led->cdev.brightness_set = lp5523_set_brightness;
 877                 res = led_classdev_register(dev, &led->cdev);
 878                 if (res < 0) {
 879                         dev_err(dev, "couldn't register led on channel %d\n",
 880                                 chan);
 881                         return res;
 882                 }
 883                 res = sysfs_create_group(&led->cdev.dev->kobj,
 884                                 &lp5523_led_attribute_group);
 885                 if (res < 0) {
 886                         dev_err(dev, "couldn't register current attribute\n");
 887                         led_classdev_unregister(&led->cdev);
 888                         return res;
 889                 }
 890         } else {
 891                 led->led_current = 0;
 892         }
 893         return 0;
 894 }
 895
 896 static struct i2c_driver lp5523_driver;
 897
 898 static int lp5523_probe(struct i2c_client *client,
 899                         const struct i2c_device_id *id)
 900 {
 901         struct lp5523_chip              *chip;
 902         struct lp5523_platform_data     *pdata;
 903         int ret, i, led;
 904
 905         chip = kzalloc(sizeof(*chip), GFP_KERNEL);
 906         if (!chip)
 907                 return -ENOMEM;
 908
 909         i2c_set_clientdata(client, chip);
 910         chip->client = client;
 911
 912         pdata = client->dev.platform_data;
 913
 914         if (!pdata) {
 915                 dev_err(&client->dev, "no platform data\n");
 916                 ret = -EINVAL;
 917                 goto fail1;
 918         }
 919
 920         mutex_init(&chip->lock);
 921
 922         chip->pdata   = pdata;
 923
 924         if (pdata->setup_resources) {
 925                 ret = pdata->setup_resources();
 926                 if (ret < 0)
 927                         goto fail1;
 928         }
 929
 930         if (pdata->enable) {
 931                 pdata->enable(0);
 932                 usleep_range(1000, 2000); /* Keep enable down at least 1ms */
 933                 pdata->enable(1);
 934                 usleep_range(1000, 2000); /* 500us abs min. */
 935         }
 936
 937         lp5523_write(client, LP5523_REG_RESET, 0xff);
 938         usleep_range(10000, 20000); /*
 939                                      * Exact value is not available. 10 - 20ms
 940                                      * appears to be enough for reset.
 941                                      */
 942         ret = lp5523_detect(client);
 943         if (ret)
 944                 goto fail2;
 945
 946         dev_info(&client->dev, "LP5523 Programmable led chip found\n");
 947
 948         /* Initialize engines */
 949         for (i = 0; i < ARRAY_SIZE(chip->engines); i++) {
 950                 ret = lp5523_init_engine(&chip->engines[i], i + 1);
 951                 if (ret) {
 952                         dev_err(&client->dev, "error initializing engine\n");
 953                         goto fail2;
 954                 }
 955         }
 956         ret = lp5523_configure(client);
 957         if (ret < 0) {
 958                 dev_err(&client->dev, "error configuring chip\n");
 959                 goto fail2;
 960         }
 961
 962         /* Initialize leds */
 963         chip->num_channels = pdata->num_channels;
 964         chip->num_leds = 0;
 965         led = 0;
 966         for (i = 0; i < pdata->num_channels; i++) {
 967                 /* Do not initialize channels that are not connected */
 968                 if (pdata->led_config[i].led_current == 0)
 969                         continue;
 970
 971                 ret = lp5523_init_led(&chip->leds[led], &client->dev, i, pdata);
 972                 if (ret) {
 973                         dev_err(&client->dev, "error initializing leds\n");
 974                         goto fail3;
 975                 }
 976                 chip->num_leds++;
 977
 978                 chip->leds[led].id = led;
 979                 /* Set LED current */
 980                 lp5523_write(client,
 981                           LP5523_REG_LED_CURRENT_BASE + chip->leds[led].chan_nr,
 982                           chip->leds[led].led_current);
 983
 984                 INIT_WORK(&(chip->leds[led].brightness_work),
 985                         lp5523_led_brightness_work);
 986
 987                 led++;
 988         }
 989
 990         ret = lp5523_register_sysfs(client);
 991         if (ret) {
 992                 dev_err(&client->dev, "registering sysfs failed\n");
 993                 goto fail3;
 994         }
 995         return ret;
 996 fail3:
 997         for (i = 0; i < chip->num_leds; i++) {
 998                 led_classdev_unregister(&chip->leds[i].cdev);
 999                 cancel_work_sync(&chip->leds[i].brightness_work);
1000         }
1001 fail2:
1002         if (pdata->enable)
1003                 pdata->enable(0);
1004         if (pdata->release_resources)
1005                 pdata->release_resources();
1006 fail1:
1007         kfree(chip);
1008         return ret;
1009 }
1010
1011 static int lp5523_remove(struct i2c_client *client)
1012 {
1013         struct lp5523_chip *chip = i2c_get_clientdata(client);
1014         int i;
1015
1016         lp5523_unregister_sysfs(client);
1017
1018         for (i = 0; i < chip->num_leds; i++) {
1019                 led_classdev_unregister(&chip->leds[i].cdev);
1020                 cancel_work_sync(&chip->leds[i].brightness_work);
1021         }
1022
1023         if (chip->pdata->enable)
1024                 chip->pdata->enable(0);
1025         if (chip->pdata->release_resources)
1026                 chip->pdata->release_resources();
1027         kfree(chip);
1028         return 0;
1029 }
1030
1031 static const struct i2c_device_id lp5523_id[] = {
1032         { "lp5523", 0 },
1033         { }
1034 };
1035
1036 MODULE_DEVICE_TABLE(i2c, lp5523_id);
1037
1038 static struct i2c_driver lp5523_driver = {
1039         .driver = {
1040                 .name   = "lp5523",
1041         },
1042         .probe          = lp5523_probe,
1043         .remove         = lp5523_remove,
1044         .id_table       = lp5523_id,
1045 };
1046
1047 static int __init lp5523_init(void)
1048 {
1049         int ret;
1050
1051         ret = i2c_add_driver(&lp5523_driver);
1052
1053         if (ret < 0)
1054                 printk(KERN_ALERT "Adding lp5523 driver failed\n");
1055
1056         return ret;
1057 }
1058
1059 static void __exit lp5523_exit(void)
1060 {
1061         i2c_del_driver(&lp5523_driver);
1062 }
1063
1064 module_init(lp5523_init);
1065 module_exit(lp5523_exit);
1066
1067 MODULE_AUTHOR("Mathias Nyman <mathias.nyman@nokia.com>");
1068 MODULE_DESCRIPTION("LP5523 LED engine");
1069 MODULE_LICENSE("GPL");