linux/drivers/leds/leds-lp5523.c
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   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
 107enum lp5523_chip_id {
 108        LP5523,
 109        LP55231,
 110};
 111
 112struct lp5523_engine {
 113        int             id;
 114        u8              mode;
 115        u8              prog_page;
 116        u8              mux_page;
 117        u16             led_mux;
 118        u8              engine_mask;
 119};
 120
 121struct lp5523_led {
 122        int                     id;
 123        u8                      chan_nr;
 124        u8                      led_current;
 125        u8                      max_current;
 126        struct led_classdev     cdev;
 127        struct work_struct      brightness_work;
 128        u8                      brightness;
 129};
 130
 131struct lp5523_chip {
 132        struct mutex            lock; /* Serialize control */
 133        struct i2c_client       *client;
 134        struct lp5523_engine    engines[LP5523_ENGINES];
 135        struct lp5523_led       leds[LP5523_LEDS];
 136        struct lp5523_platform_data *pdata;
 137        u8                      num_channels;
 138        u8                      num_leds;
 139};
 140
 141static inline struct lp5523_led *cdev_to_led(struct led_classdev *cdev)
 142{
 143        return container_of(cdev, struct lp5523_led, cdev);
 144}
 145
 146static inline struct lp5523_chip *engine_to_lp5523(struct lp5523_engine *engine)
 147{
 148        return container_of(engine, struct lp5523_chip,
 149                            engines[engine->id - 1]);
 150}
 151
 152static inline struct lp5523_chip *led_to_lp5523(struct lp5523_led *led)
 153{
 154        return container_of(led, struct lp5523_chip,
 155                            leds[led->id]);
 156}
 157
 158static void lp5523_set_mode(struct lp5523_engine *engine, u8 mode);
 159static int lp5523_set_engine_mode(struct lp5523_engine *engine, u8 mode);
 160static int lp5523_load_program(struct lp5523_engine *engine, const u8 *pattern);
 161
 162static void lp5523_led_brightness_work(struct work_struct *work);
 163
 164static int lp5523_write(struct i2c_client *client, u8 reg, u8 value)
 165{
 166        return i2c_smbus_write_byte_data(client, reg, value);
 167}
 168
 169static int lp5523_read(struct i2c_client *client, u8 reg, u8 *buf)
 170{
 171        s32 ret = i2c_smbus_read_byte_data(client, reg);
 172
 173        if (ret < 0)
 174                return -EIO;
 175
 176        *buf = ret;
 177        return 0;
 178}
 179
 180static int lp5523_detect(struct i2c_client *client)
 181{
 182        int ret;
 183        u8 buf;
 184
 185        ret = lp5523_write(client, LP5523_REG_ENABLE, LP5523_ENABLE);
 186        if (ret)
 187                return ret;
 188        ret = lp5523_read(client, LP5523_REG_ENABLE, &buf);
 189        if (ret)
 190                return ret;
 191        if (buf == 0x40)
 192                return 0;
 193        else
 194                return -ENODEV;
 195}
 196
 197static int lp5523_configure(struct i2c_client *client)
 198{
 199        struct lp5523_chip *chip = i2c_get_clientdata(client);
 200        int ret = 0;
 201        u8 status;
 202
 203        /* one pattern per engine setting led mux start and stop addresses */
 204        static const u8 pattern[][LP5523_PROGRAM_LENGTH] =  {
 205                { 0x9c, 0x30, 0x9c, 0xb0, 0x9d, 0x80, 0xd8, 0x00, 0},
 206                { 0x9c, 0x40, 0x9c, 0xc0, 0x9d, 0x80, 0xd8, 0x00, 0},
 207                { 0x9c, 0x50, 0x9c, 0xd0, 0x9d, 0x80, 0xd8, 0x00, 0},
 208        };
 209
 210        ret |= lp5523_write(client, LP5523_REG_ENABLE, LP5523_ENABLE);
 211        /* Chip startup time is 500 us, 1 - 2 ms gives some margin */
 212        usleep_range(1000, 2000);
 213
 214        ret |= lp5523_write(client, LP5523_REG_CONFIG,
 215                            LP5523_AUTO_INC | LP5523_PWR_SAVE |
 216                            LP5523_CP_AUTO | LP5523_AUTO_CLK |
 217                            LP5523_PWM_PWR_SAVE);
 218
 219        /* turn on all leds */
 220        ret |= lp5523_write(client, LP5523_REG_ENABLE_LEDS_MSB, 0x01);
 221        ret |= lp5523_write(client, LP5523_REG_ENABLE_LEDS_LSB, 0xff);
 222
 223        /* hardcode 32 bytes of memory for each engine from program memory */
 224        ret |= lp5523_write(client, LP5523_REG_CH1_PROG_START, 0x00);
 225        ret |= lp5523_write(client, LP5523_REG_CH2_PROG_START, 0x10);
 226        ret |= lp5523_write(client, LP5523_REG_CH3_PROG_START, 0x20);
 227
 228        /* write led mux address space for each channel */
 229        ret |= lp5523_load_program(&chip->engines[0], pattern[0]);
 230        ret |= lp5523_load_program(&chip->engines[1], pattern[1]);
 231        ret |= lp5523_load_program(&chip->engines[2], pattern[2]);
 232
 233        if (ret) {
 234                dev_err(&client->dev, "could not load mux programs\n");
 235                return -1;
 236        }
 237
 238        /* set all engines exec state and mode to run 00101010 */
 239        ret |= lp5523_write(client, LP5523_REG_ENABLE,
 240                            (LP5523_CMD_RUN | LP5523_ENABLE));
 241
 242        ret |= lp5523_write(client, LP5523_REG_OP_MODE, LP5523_CMD_RUN);
 243
 244        if (ret) {
 245                dev_err(&client->dev, "could not start mux programs\n");
 246                return -1;
 247        }
 248
 249        /* Let the programs run for couple of ms and check the engine status */
 250        usleep_range(3000, 6000);
 251        lp5523_read(client, LP5523_REG_STATUS, &status);
 252        status &= LP5523_ENG_STATUS_MASK;
 253
 254        if (status == LP5523_ENG_STATUS_MASK) {
 255                dev_dbg(&client->dev, "all engines configured\n");
 256        } else {
 257                dev_info(&client->dev, "status == %x\n", status);
 258                dev_err(&client->dev, "cound not configure LED engine\n");
 259                return -1;
 260        }
 261
 262        dev_info(&client->dev, "disabling engines\n");
 263
 264        ret |= lp5523_write(client, LP5523_REG_OP_MODE, LP5523_CMD_DISABLED);
 265
 266        return ret;
 267}
 268
 269static int lp5523_set_engine_mode(struct lp5523_engine *engine, u8 mode)
 270{
 271        struct lp5523_chip *chip = engine_to_lp5523(engine);
 272        struct i2c_client *client = chip->client;
 273        int ret;
 274        u8 engine_state;
 275
 276        ret = lp5523_read(client, LP5523_REG_OP_MODE, &engine_state);
 277        if (ret)
 278                goto fail;
 279
 280        engine_state &= ~(engine->engine_mask);
 281
 282        /* set mode only for this engine */
 283        mode &= engine->engine_mask;
 284
 285        engine_state |= mode;
 286
 287        ret |= lp5523_write(client, LP5523_REG_OP_MODE, engine_state);
 288fail:
 289        return ret;
 290}
 291
 292static int lp5523_load_mux(struct lp5523_engine *engine, u16 mux)
 293{
 294        struct lp5523_chip *chip = engine_to_lp5523(engine);
 295        struct i2c_client *client = chip->client;
 296        int ret = 0;
 297
 298        ret |= lp5523_set_engine_mode(engine, LP5523_CMD_LOAD);
 299
 300        ret |= lp5523_write(client, LP5523_REG_PROG_PAGE_SEL, engine->mux_page);
 301        ret |= lp5523_write(client, LP5523_REG_PROG_MEM,
 302                            (u8)(mux >> 8));
 303        ret |= lp5523_write(client, LP5523_REG_PROG_MEM + 1, (u8)(mux));
 304        engine->led_mux = mux;
 305
 306        return ret;
 307}
 308
 309static int lp5523_load_program(struct lp5523_engine *engine, const u8 *pattern)
 310{
 311        struct lp5523_chip *chip = engine_to_lp5523(engine);
 312        struct i2c_client *client = chip->client;
 313
 314        int ret = 0;
 315
 316        ret |= lp5523_set_engine_mode(engine, LP5523_CMD_LOAD);
 317
 318        ret |= lp5523_write(client, LP5523_REG_PROG_PAGE_SEL,
 319                            engine->prog_page);
 320        ret |= i2c_smbus_write_i2c_block_data(client, LP5523_REG_PROG_MEM,
 321                                              LP5523_PROGRAM_LENGTH, pattern);
 322
 323        return ret;
 324}
 325
 326static int lp5523_run_program(struct lp5523_engine *engine)
 327{
 328        struct lp5523_chip *chip = engine_to_lp5523(engine);
 329        struct i2c_client *client = chip->client;
 330        int ret;
 331
 332        ret = lp5523_write(client, LP5523_REG_ENABLE,
 333                                        LP5523_CMD_RUN | LP5523_ENABLE);
 334        if (ret)
 335                goto fail;
 336
 337        ret = lp5523_set_engine_mode(engine, LP5523_CMD_RUN);
 338fail:
 339        return ret;
 340}
 341
 342static int lp5523_mux_parse(const char *buf, u16 *mux, size_t len)
 343{
 344        int i;
 345        u16 tmp_mux = 0;
 346
 347        len = min_t(int, len, LP5523_LEDS);
 348        for (i = 0; i < len; i++) {
 349                switch (buf[i]) {
 350                case '1':
 351                        tmp_mux |= (1 << i);
 352                        break;
 353                case '0':
 354                        break;
 355                case '\n':
 356                        i = len;
 357                        break;
 358                default:
 359                        return -1;
 360                }
 361        }
 362        *mux = tmp_mux;
 363
 364        return 0;
 365}
 366
 367static void lp5523_mux_to_array(u16 led_mux, char *array)
 368{
 369        int i, pos = 0;
 370        for (i = 0; i < LP5523_LEDS; i++)
 371                pos += sprintf(array + pos, "%x", LED_ACTIVE(led_mux, i));
 372
 373        array[pos] = '\0';
 374}
 375
 376/*--------------------------------------------------------------*/
 377/*                      Sysfs interface                         */
 378/*--------------------------------------------------------------*/
 379
 380static ssize_t show_engine_leds(struct device *dev,
 381                            struct device_attribute *attr,
 382                            char *buf, int nr)
 383{
 384        struct i2c_client *client = to_i2c_client(dev);
 385        struct lp5523_chip *chip = i2c_get_clientdata(client);
 386        char mux[LP5523_LEDS + 1];
 387
 388        lp5523_mux_to_array(chip->engines[nr - 1].led_mux, mux);
 389
 390        return sprintf(buf, "%s\n", mux);
 391}
 392
 393#define show_leds(nr)                                                   \
 394static ssize_t show_engine##nr##_leds(struct device *dev,               \
 395                            struct device_attribute *attr,              \
 396                            char *buf)                                  \
 397{                                                                       \
 398        return show_engine_leds(dev, attr, buf, nr);                    \
 399}
 400show_leds(1)
 401show_leds(2)
 402show_leds(3)
 403
 404static ssize_t store_engine_leds(struct device *dev,
 405                             struct device_attribute *attr,
 406                             const char *buf, size_t len, int nr)
 407{
 408        struct i2c_client *client = to_i2c_client(dev);
 409        struct lp5523_chip *chip = i2c_get_clientdata(client);
 410        u16 mux = 0;
 411        ssize_t ret;
 412
 413        if (lp5523_mux_parse(buf, &mux, len))
 414                return -EINVAL;
 415
 416        mutex_lock(&chip->lock);
 417        ret = -EINVAL;
 418        if (chip->engines[nr - 1].mode != LP5523_CMD_LOAD)
 419                goto leave;
 420
 421        if (lp5523_load_mux(&chip->engines[nr - 1], mux))
 422                goto leave;
 423
 424        ret = len;
 425leave:
 426        mutex_unlock(&chip->lock);
 427        return ret;
 428}
 429
 430#define store_leds(nr)                                          \
 431static ssize_t store_engine##nr##_leds(struct device *dev,      \
 432                             struct device_attribute *attr,     \
 433                             const char *buf, size_t len)       \
 434{                                                               \
 435        return store_engine_leds(dev, attr, buf, len, nr);      \
 436}
 437store_leds(1)
 438store_leds(2)
 439store_leds(3)
 440
 441static ssize_t lp5523_selftest(struct device *dev,
 442                               struct device_attribute *attr,
 443                               char *buf)
 444{
 445        struct i2c_client *client = to_i2c_client(dev);
 446        struct lp5523_chip *chip = i2c_get_clientdata(client);
 447        int i, ret, pos = 0;
 448        int led = 0;
 449        u8 status, adc, vdd;
 450
 451        mutex_lock(&chip->lock);
 452
 453        ret = lp5523_read(chip->client, LP5523_REG_STATUS, &status);
 454        if (ret < 0)
 455                goto fail;
 456
 457        /* Check that ext clock is really in use if requested */
 458        if ((chip->pdata) && (chip->pdata->clock_mode == LP5523_CLOCK_EXT))
 459                if  ((status & LP5523_EXT_CLK_USED) == 0)
 460                        goto fail;
 461
 462        /* Measure VDD (i.e. VBAT) first (channel 16 corresponds to VDD) */
 463        lp5523_write(chip->client, LP5523_REG_LED_TEST_CTRL,
 464                                    LP5523_EN_LEDTEST | 16);
 465        usleep_range(3000, 6000); /* ADC conversion time is typically 2.7 ms */
 466        ret = lp5523_read(chip->client, LP5523_REG_STATUS, &status);
 467        if (!(status & LP5523_LEDTEST_DONE))
 468                usleep_range(3000, 6000); /* Was not ready. Wait little bit */
 469
 470        ret |= lp5523_read(chip->client, LP5523_REG_LED_TEST_ADC, &vdd);
 471        vdd--;  /* There may be some fluctuation in measurement */
 472
 473        for (i = 0; i < LP5523_LEDS; i++) {
 474                /* Skip non-existing channels */
 475                if (chip->pdata->led_config[i].led_current == 0)
 476                        continue;
 477
 478                /* Set default current */
 479                lp5523_write(chip->client,
 480                        LP5523_REG_LED_CURRENT_BASE + i,
 481                        chip->pdata->led_config[i].led_current);
 482
 483                lp5523_write(chip->client, LP5523_REG_LED_PWM_BASE + i, 0xff);
 484                /* let current stabilize 2 - 4ms before measurements start */
 485                usleep_range(2000, 4000);
 486                lp5523_write(chip->client,
 487                             LP5523_REG_LED_TEST_CTRL,
 488                             LP5523_EN_LEDTEST | i);
 489                /* ADC conversion time is 2.7 ms typically */
 490                usleep_range(3000, 6000);
 491                ret = lp5523_read(chip->client, LP5523_REG_STATUS, &status);
 492                if (!(status & LP5523_LEDTEST_DONE))
 493                        usleep_range(3000, 6000);/* Was not ready. Wait. */
 494                ret |= lp5523_read(chip->client, LP5523_REG_LED_TEST_ADC, &adc);
 495
 496                if (adc >= vdd || adc < LP5523_ADC_SHORTCIRC_LIM)
 497                        pos += sprintf(buf + pos, "LED %d FAIL\n", i);
 498
 499                lp5523_write(chip->client, LP5523_REG_LED_PWM_BASE + i, 0x00);
 500
 501                /* Restore current */
 502                lp5523_write(chip->client,
 503                        LP5523_REG_LED_CURRENT_BASE + i,
 504                        chip->leds[led].led_current);
 505                led++;
 506        }
 507        if (pos == 0)
 508                pos = sprintf(buf, "OK\n");
 509        goto release_lock;
 510fail:
 511        pos = sprintf(buf, "FAIL\n");
 512
 513release_lock:
 514        mutex_unlock(&chip->lock);
 515
 516        return pos;
 517}
 518
 519static void lp5523_set_brightness(struct led_classdev *cdev,
 520                             enum led_brightness brightness)
 521{
 522        struct lp5523_led *led = cdev_to_led(cdev);
 523
 524        led->brightness = (u8)brightness;
 525
 526        schedule_work(&led->brightness_work);
 527}
 528
 529static void lp5523_led_brightness_work(struct work_struct *work)
 530{
 531        struct lp5523_led *led = container_of(work,
 532                                              struct lp5523_led,
 533                                              brightness_work);
 534        struct lp5523_chip *chip = led_to_lp5523(led);
 535        struct i2c_client *client = chip->client;
 536
 537        mutex_lock(&chip->lock);
 538
 539        lp5523_write(client, LP5523_REG_LED_PWM_BASE + led->chan_nr,
 540                     led->brightness);
 541
 542        mutex_unlock(&chip->lock);
 543}
 544
 545static int lp5523_do_store_load(struct lp5523_engine *engine,
 546                                const char *buf, size_t len)
 547{
 548        struct lp5523_chip *chip = engine_to_lp5523(engine);
 549        struct i2c_client *client = chip->client;
 550        int  ret, nrchars, offset = 0, i = 0;
 551        char c[3];
 552        unsigned cmd;
 553        u8 pattern[LP5523_PROGRAM_LENGTH] = {0};
 554
 555        if (engine->mode != LP5523_CMD_LOAD)
 556                return -EINVAL;
 557
 558        while ((offset < len - 1) && (i < LP5523_PROGRAM_LENGTH)) {
 559                /* separate sscanfs because length is working only for %s */
 560                ret = sscanf(buf + offset, "%2s%n ", c, &nrchars);
 561                ret = sscanf(c, "%2x", &cmd);
 562                if (ret != 1)
 563                        goto fail;
 564                pattern[i] = (u8)cmd;
 565
 566                offset += nrchars;
 567                i++;
 568        }
 569
 570        /* Each instruction is 16bit long. Check that length is even */
 571        if (i % 2)
 572                goto fail;
 573
 574        mutex_lock(&chip->lock);
 575        ret = lp5523_load_program(engine, pattern);
 576        mutex_unlock(&chip->lock);
 577
 578        if (ret) {
 579                dev_err(&client->dev, "failed loading pattern\n");
 580                return ret;
 581        }
 582
 583        return len;
 584fail:
 585        dev_err(&client->dev, "wrong pattern format\n");
 586        return -EINVAL;
 587}
 588
 589static ssize_t store_engine_load(struct device *dev,
 590                                     struct device_attribute *attr,
 591                                     const char *buf, size_t len, int nr)
 592{
 593        struct i2c_client *client = to_i2c_client(dev);
 594        struct lp5523_chip *chip = i2c_get_clientdata(client);
 595        return lp5523_do_store_load(&chip->engines[nr - 1], buf, len);
 596}
 597
 598#define store_load(nr)                                                  \
 599static ssize_t store_engine##nr##_load(struct device *dev,              \
 600                                     struct device_attribute *attr,     \
 601                                     const char *buf, size_t len)       \
 602{                                                                       \
 603        return store_engine_load(dev, attr, buf, len, nr);              \
 604}
 605store_load(1)
 606store_load(2)
 607store_load(3)
 608
 609static ssize_t show_engine_mode(struct device *dev,
 610                                struct device_attribute *attr,
 611                                char *buf, int nr)
 612{
 613        struct i2c_client *client = to_i2c_client(dev);
 614        struct lp5523_chip *chip = i2c_get_clientdata(client);
 615        switch (chip->engines[nr - 1].mode) {
 616        case LP5523_CMD_RUN:
 617                return sprintf(buf, "run\n");
 618        case LP5523_CMD_LOAD:
 619                return sprintf(buf, "load\n");
 620        case LP5523_CMD_DISABLED:
 621                return sprintf(buf, "disabled\n");
 622        default:
 623                return sprintf(buf, "disabled\n");
 624        }
 625}
 626
 627#define show_mode(nr)                                                   \
 628static ssize_t show_engine##nr##_mode(struct device *dev,               \
 629                                    struct device_attribute *attr,      \
 630                                    char *buf)                          \
 631{                                                                       \
 632        return show_engine_mode(dev, attr, buf, nr);                    \
 633}
 634show_mode(1)
 635show_mode(2)
 636show_mode(3)
 637
 638static ssize_t store_engine_mode(struct device *dev,
 639                                 struct device_attribute *attr,
 640                                 const char *buf, size_t len, int nr)
 641{
 642        struct i2c_client *client = to_i2c_client(dev);
 643        struct lp5523_chip *chip = i2c_get_clientdata(client);
 644        struct lp5523_engine *engine = &chip->engines[nr - 1];
 645        mutex_lock(&chip->lock);
 646
 647        if (!strncmp(buf, "run", 3))
 648                lp5523_set_mode(engine, LP5523_CMD_RUN);
 649        else if (!strncmp(buf, "load", 4))
 650                lp5523_set_mode(engine, LP5523_CMD_LOAD);
 651        else if (!strncmp(buf, "disabled", 8))
 652                lp5523_set_mode(engine, LP5523_CMD_DISABLED);
 653
 654        mutex_unlock(&chip->lock);
 655        return len;
 656}
 657
 658#define store_mode(nr)                                                  \
 659static ssize_t store_engine##nr##_mode(struct device *dev,              \
 660                                     struct device_attribute *attr,     \
 661                                     const char *buf, size_t len)       \
 662{                                                                       \
 663        return store_engine_mode(dev, attr, buf, len, nr);              \
 664}
 665store_mode(1)
 666store_mode(2)
 667store_mode(3)
 668
 669static ssize_t show_max_current(struct device *dev,
 670                            struct device_attribute *attr,
 671                            char *buf)
 672{
 673        struct led_classdev *led_cdev = dev_get_drvdata(dev);
 674        struct lp5523_led *led = cdev_to_led(led_cdev);
 675
 676        return sprintf(buf, "%d\n", led->max_current);
 677}
 678
 679static ssize_t show_current(struct device *dev,
 680                            struct device_attribute *attr,
 681                            char *buf)
 682{
 683        struct led_classdev *led_cdev = dev_get_drvdata(dev);
 684        struct lp5523_led *led = cdev_to_led(led_cdev);
 685
 686        return sprintf(buf, "%d\n", led->led_current);
 687}
 688
 689static ssize_t store_current(struct device *dev,
 690                             struct device_attribute *attr,
 691                             const char *buf, size_t len)
 692{
 693        struct led_classdev *led_cdev = dev_get_drvdata(dev);
 694        struct lp5523_led *led = cdev_to_led(led_cdev);
 695        struct lp5523_chip *chip = led_to_lp5523(led);
 696        ssize_t ret;
 697        unsigned long curr;
 698
 699        if (strict_strtoul(buf, 0, &curr))
 700                return -EINVAL;
 701
 702        if (curr > led->max_current)
 703                return -EINVAL;
 704
 705        mutex_lock(&chip->lock);
 706        ret = lp5523_write(chip->client,
 707                        LP5523_REG_LED_CURRENT_BASE + led->chan_nr,
 708                        (u8)curr);
 709        mutex_unlock(&chip->lock);
 710
 711        if (ret < 0)
 712                return ret;
 713
 714        led->led_current = (u8)curr;
 715
 716        return len;
 717}
 718
 719/* led class device attributes */
 720static DEVICE_ATTR(led_current, S_IRUGO | S_IWUSR, show_current, store_current);
 721static DEVICE_ATTR(max_current, S_IRUGO , show_max_current, NULL);
 722
 723static struct attribute *lp5523_led_attributes[] = {
 724        &dev_attr_led_current.attr,
 725        &dev_attr_max_current.attr,
 726        NULL,
 727};
 728
 729static struct attribute_group lp5523_led_attribute_group = {
 730        .attrs = lp5523_led_attributes
 731};
 732
 733/* device attributes */
 734static DEVICE_ATTR(engine1_mode, S_IRUGO | S_IWUSR,
 735                   show_engine1_mode, store_engine1_mode);
 736static DEVICE_ATTR(engine2_mode, S_IRUGO | S_IWUSR,
 737                   show_engine2_mode, store_engine2_mode);
 738static DEVICE_ATTR(engine3_mode, S_IRUGO | S_IWUSR,
 739                   show_engine3_mode, store_engine3_mode);
 740static DEVICE_ATTR(engine1_leds, S_IRUGO | S_IWUSR,
 741                   show_engine1_leds, store_engine1_leds);
 742static DEVICE_ATTR(engine2_leds, S_IRUGO | S_IWUSR,
 743                   show_engine2_leds, store_engine2_leds);
 744static DEVICE_ATTR(engine3_leds, S_IRUGO | S_IWUSR,
 745                   show_engine3_leds, store_engine3_leds);
 746static DEVICE_ATTR(engine1_load, S_IWUSR, NULL, store_engine1_load);
 747static DEVICE_ATTR(engine2_load, S_IWUSR, NULL, store_engine2_load);
 748static DEVICE_ATTR(engine3_load, S_IWUSR, NULL, store_engine3_load);
 749static DEVICE_ATTR(selftest, S_IRUGO, lp5523_selftest, NULL);
 750
 751static struct attribute *lp5523_attributes[] = {
 752        &dev_attr_engine1_mode.attr,
 753        &dev_attr_engine2_mode.attr,
 754        &dev_attr_engine3_mode.attr,
 755        &dev_attr_selftest.attr,
 756        &dev_attr_engine1_load.attr,
 757        &dev_attr_engine1_leds.attr,
 758        &dev_attr_engine2_load.attr,
 759        &dev_attr_engine2_leds.attr,
 760        &dev_attr_engine3_load.attr,
 761        &dev_attr_engine3_leds.attr,
 762        NULL,
 763};
 764
 765static const struct attribute_group lp5523_group = {
 766        .attrs = lp5523_attributes,
 767};
 768
 769static int lp5523_register_sysfs(struct i2c_client *client)
 770{
 771        struct device *dev = &client->dev;
 772        int ret;
 773
 774        ret = sysfs_create_group(&dev->kobj, &lp5523_group);
 775        if (ret < 0)
 776                return ret;
 777
 778        return 0;
 779}
 780
 781static void lp5523_unregister_sysfs(struct i2c_client *client)
 782{
 783        struct lp5523_chip *chip = i2c_get_clientdata(client);
 784        struct device *dev = &client->dev;
 785        int i;
 786
 787        sysfs_remove_group(&dev->kobj, &lp5523_group);
 788
 789        for (i = 0; i < chip->num_leds; i++)
 790                sysfs_remove_group(&chip->leds[i].cdev.dev->kobj,
 791                                &lp5523_led_attribute_group);
 792}
 793
 794/*--------------------------------------------------------------*/
 795/*                      Set chip operating mode                 */
 796/*--------------------------------------------------------------*/
 797static void lp5523_set_mode(struct lp5523_engine *engine, u8 mode)
 798{
 799        /* if in that mode already do nothing, except for run */
 800        if (mode == engine->mode && mode != LP5523_CMD_RUN)
 801                return;
 802
 803        switch (mode) {
 804        case LP5523_CMD_RUN:
 805                lp5523_run_program(engine);
 806                break;
 807        case LP5523_CMD_LOAD:
 808                lp5523_set_engine_mode(engine, LP5523_CMD_DISABLED);
 809                lp5523_set_engine_mode(engine, LP5523_CMD_LOAD);
 810                break;
 811        case LP5523_CMD_DISABLED:
 812                lp5523_set_engine_mode(engine, LP5523_CMD_DISABLED);
 813                break;
 814        default:
 815                return;
 816        }
 817
 818        engine->mode = mode;
 819}
 820
 821/*--------------------------------------------------------------*/
 822/*                      Probe, Attach, Remove                   */
 823/*--------------------------------------------------------------*/
 824static int __init lp5523_init_engine(struct lp5523_engine *engine, int id)
 825{
 826        if (id < 1 || id > LP5523_ENGINES)
 827                return -1;
 828        engine->id = id;
 829        engine->engine_mask = LP5523_ENG_MASK_BASE >> SHIFT_MASK(id);
 830        engine->prog_page = id - 1;
 831        engine->mux_page = id + 2;
 832
 833        return 0;
 834}
 835
 836static int __devinit lp5523_init_led(struct lp5523_led *led, struct device *dev,
 837                           int chan, struct lp5523_platform_data *pdata,
 838                           const char *chip_name)
 839{
 840        char name[32];
 841        int res;
 842
 843        if (chan >= LP5523_LEDS)
 844                return -EINVAL;
 845
 846        if (pdata->led_config[chan].led_current) {
 847                led->led_current = pdata->led_config[chan].led_current;
 848                led->max_current = pdata->led_config[chan].max_current;
 849                led->chan_nr = pdata->led_config[chan].chan_nr;
 850
 851                if (led->chan_nr >= LP5523_LEDS) {
 852                        dev_err(dev, "Use channel numbers between 0 and %d\n",
 853                                LP5523_LEDS - 1);
 854                        return -EINVAL;
 855                }
 856
 857                if (pdata->led_config[chan].name) {
 858                        led->cdev.name = pdata->led_config[chan].name;
 859                } else {
 860                        snprintf(name, sizeof(name), "%s:channel%d",
 861                                pdata->label ? : chip_name, chan);
 862                        led->cdev.name = name;
 863                }
 864
 865                led->cdev.brightness_set = lp5523_set_brightness;
 866                res = led_classdev_register(dev, &led->cdev);
 867                if (res < 0) {
 868                        dev_err(dev, "couldn't register led on channel %d\n",
 869                                chan);
 870                        return res;
 871                }
 872                res = sysfs_create_group(&led->cdev.dev->kobj,
 873                                &lp5523_led_attribute_group);
 874                if (res < 0) {
 875                        dev_err(dev, "couldn't register current attribute\n");
 876                        led_classdev_unregister(&led->cdev);
 877                        return res;
 878                }
 879        } else {
 880                led->led_current = 0;
 881        }
 882        return 0;
 883}
 884
 885static int __devinit lp5523_probe(struct i2c_client *client,
 886                        const struct i2c_device_id *id)
 887{
 888        struct lp5523_chip              *chip;
 889        struct lp5523_platform_data     *pdata;
 890        int ret, i, led;
 891
 892        chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
 893        if (!chip)
 894                return -ENOMEM;
 895
 896        i2c_set_clientdata(client, chip);
 897        chip->client = client;
 898
 899        pdata = client->dev.platform_data;
 900
 901        if (!pdata) {
 902                dev_err(&client->dev, "no platform data\n");
 903                return -EINVAL;
 904        }
 905
 906        mutex_init(&chip->lock);
 907
 908        chip->pdata   = pdata;
 909
 910        if (pdata->setup_resources) {
 911                ret = pdata->setup_resources();
 912                if (ret < 0)
 913                        return ret;
 914        }
 915
 916        if (pdata->enable) {
 917                pdata->enable(0);
 918                usleep_range(1000, 2000); /* Keep enable down at least 1ms */
 919                pdata->enable(1);
 920                usleep_range(1000, 2000); /* 500us abs min. */
 921        }
 922
 923        lp5523_write(client, LP5523_REG_RESET, 0xff);
 924        usleep_range(10000, 20000); /*
 925                                     * Exact value is not available. 10 - 20ms
 926                                     * appears to be enough for reset.
 927                                     */
 928        ret = lp5523_detect(client);
 929        if (ret)
 930                goto fail1;
 931
 932        dev_info(&client->dev, "%s Programmable led chip found\n", id->name);
 933
 934        /* Initialize engines */
 935        for (i = 0; i < ARRAY_SIZE(chip->engines); i++) {
 936                ret = lp5523_init_engine(&chip->engines[i], i + 1);
 937                if (ret) {
 938                        dev_err(&client->dev, "error initializing engine\n");
 939                        goto fail1;
 940                }
 941        }
 942        ret = lp5523_configure(client);
 943        if (ret < 0) {
 944                dev_err(&client->dev, "error configuring chip\n");
 945                goto fail1;
 946        }
 947
 948        /* Initialize leds */
 949        chip->num_channels = pdata->num_channels;
 950        chip->num_leds = 0;
 951        led = 0;
 952        for (i = 0; i < pdata->num_channels; i++) {
 953                /* Do not initialize channels that are not connected */
 954                if (pdata->led_config[i].led_current == 0)
 955                        continue;
 956
 957                INIT_WORK(&chip->leds[led].brightness_work,
 958                        lp5523_led_brightness_work);
 959
 960                ret = lp5523_init_led(&chip->leds[led], &client->dev, i, pdata,
 961                                id->name);
 962                if (ret) {
 963                        dev_err(&client->dev, "error initializing leds\n");
 964                        goto fail2;
 965                }
 966                chip->num_leds++;
 967
 968                chip->leds[led].id = led;
 969                /* Set LED current */
 970                lp5523_write(client,
 971                          LP5523_REG_LED_CURRENT_BASE + chip->leds[led].chan_nr,
 972                          chip->leds[led].led_current);
 973
 974                led++;
 975        }
 976
 977        ret = lp5523_register_sysfs(client);
 978        if (ret) {
 979                dev_err(&client->dev, "registering sysfs failed\n");
 980                goto fail2;
 981        }
 982        return ret;
 983fail2:
 984        for (i = 0; i < chip->num_leds; i++) {
 985                led_classdev_unregister(&chip->leds[i].cdev);
 986                flush_work(&chip->leds[i].brightness_work);
 987        }
 988fail1:
 989        if (pdata->enable)
 990                pdata->enable(0);
 991        if (pdata->release_resources)
 992                pdata->release_resources();
 993        return ret;
 994}
 995
 996static int lp5523_remove(struct i2c_client *client)
 997{
 998        struct lp5523_chip *chip = i2c_get_clientdata(client);
 999        int i;
1000
1001        /* Disable engine mode */
1002        lp5523_write(client, LP5523_REG_OP_MODE, LP5523_CMD_DISABLED);
1003
1004        lp5523_unregister_sysfs(client);
1005
1006        for (i = 0; i < chip->num_leds; i++) {
1007                led_classdev_unregister(&chip->leds[i].cdev);
1008                flush_work(&chip->leds[i].brightness_work);
1009        }
1010
1011        if (chip->pdata->enable)
1012                chip->pdata->enable(0);
1013        if (chip->pdata->release_resources)
1014                chip->pdata->release_resources();
1015        return 0;
1016}
1017
1018static const struct i2c_device_id lp5523_id[] = {
1019        { "lp5523",  LP5523 },
1020        { "lp55231", LP55231 },
1021        { }
1022};
1023
1024MODULE_DEVICE_TABLE(i2c, lp5523_id);
1025
1026static struct i2c_driver lp5523_driver = {
1027        .driver = {
1028                .name   = "lp5523x",
1029        },
1030        .probe          = lp5523_probe,
1031        .remove         = lp5523_remove,
1032        .id_table       = lp5523_id,
1033};
1034
1035module_i2c_driver(lp5523_driver);
1036
1037MODULE_AUTHOR("Mathias Nyman <mathias.nyman@nokia.com>");
1038MODULE_DESCRIPTION("LP5523 LED engine");
1039MODULE_LICENSE("GPL");
1040
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