drivers/leds/leds-lp5523.c

   1 /*
   2  * lp5523.c - LP5523 LED Driver
   3  *
   4  * Copyright (C) 2010 Nokia Corporation
   5  * Copyright (C) 2012 Texas Instruments
   6  *
   7  * Contact: Samu Onkalo <samu.p.onkalo@nokia.com>
   8  *          Milo(Woogyom) Kim <milo.kim@ti.com>
   9  *
  10  * This program is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU General Public License
  12  * version 2 as published by the Free Software Foundation.
  13  *
  14  * This program is distributed in the hope that it will be useful, but
  15  * WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  17  * General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
  22  * 02110-1301 USA
  23  */
  24
  25 #include <linux/delay.h>
  26 #include <linux/firmware.h>
  27 #include <linux/i2c.h>
  28 #include <linux/init.h>
  29 #include <linux/leds.h>
  30 #include <linux/module.h>
  31 #include <linux/mutex.h>
  32 #include <linux/platform_data/leds-lp55xx.h>
  33 #include <linux/slab.h>
  34
  35 #include "leds-lp55xx-common.h"
  36
  37 #define LP5523_PROGRAM_LENGTH           32
  38 #define LP5523_MAX_LEDS                 9
  39
  40 /* Registers */
  41 #define LP5523_REG_ENABLE               0x00
  42 #define LP5523_REG_OP_MODE              0x01
  43 #define LP5523_REG_ENABLE_LEDS_MSB      0x04
  44 #define LP5523_REG_ENABLE_LEDS_LSB      0x05
  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_STATUS               0x3A
  49 #define LP5523_REG_RESET                0x3D
  50 #define LP5523_REG_LED_TEST_CTRL        0x41
  51 #define LP5523_REG_LED_TEST_ADC         0x42
  52 #define LP5523_REG_PROG_PAGE_SEL        0x4F
  53 #define LP5523_REG_PROG_MEM             0x50
  54
  55 /* Bit description in registers */
  56 #define LP5523_ENABLE                   0x40
  57 #define LP5523_AUTO_INC                 0x40
  58 #define LP5523_PWR_SAVE                 0x20
  59 #define LP5523_PWM_PWR_SAVE             0x04
  60 #define LP5523_CP_AUTO                  0x18
  61 #define LP5523_AUTO_CLK                 0x02
  62
  63 #define LP5523_EN_LEDTEST               0x80
  64 #define LP5523_LEDTEST_DONE             0x80
  65 #define LP5523_RESET                    0xFF
  66 #define LP5523_ADC_SHORTCIRC_LIM        80
  67 #define LP5523_EXT_CLK_USED             0x08
  68
  69 /* Memory Page Selection */
  70 #define LP5523_PAGE_ENG1                0
  71 #define LP5523_PAGE_ENG2                1
  72 #define LP5523_PAGE_ENG3                2
  73
  74 /* Program Memory Operations */
  75 #define LP5523_MODE_ENG1_M              0x30    /* Operation Mode Register */
  76 #define LP5523_MODE_ENG2_M              0x0C
  77 #define LP5523_MODE_ENG3_M              0x03
  78 #define LP5523_LOAD_ENG1                0x10
  79 #define LP5523_LOAD_ENG2                0x04
  80 #define LP5523_LOAD_ENG3                0x01
  81
  82 #define LP5523_ENG1_IS_LOADING(mode)    \
  83         ((mode & LP5523_MODE_ENG1_M) == LP5523_LOAD_ENG1)
  84 #define LP5523_ENG2_IS_LOADING(mode)    \
  85         ((mode & LP5523_MODE_ENG2_M) == LP5523_LOAD_ENG2)
  86 #define LP5523_ENG3_IS_LOADING(mode)    \
  87         ((mode & LP5523_MODE_ENG3_M) == LP5523_LOAD_ENG3)
  88
  89 #define LP5523_EXEC_ENG1_M              0x30    /* Enable Register */
  90 #define LP5523_EXEC_ENG2_M              0x0C
  91 #define LP5523_EXEC_ENG3_M              0x03
  92 #define LP5523_EXEC_M                   0x3F
  93 #define LP5523_RUN_ENG1                 0x20
  94 #define LP5523_RUN_ENG2                 0x08
  95 #define LP5523_RUN_ENG3                 0x02
  96
  97 enum lp5523_chip_id {
  98         LP5523,
  99         LP55231,
 100 };
 101
 102 static inline void lp5523_wait_opmode_done(void)
 103 {
 104         usleep_range(1000, 2000);
 105 }
 106
 107 static void lp5523_set_led_current(struct lp55xx_led *led, u8 led_current)
 108 {
 109         led->led_current = led_current;
 110         lp55xx_write(led->chip, LP5523_REG_LED_CURRENT_BASE + led->chan_nr,
 111                 led_current);
 112 }
 113
 114 static int lp5523_post_init_device(struct lp55xx_chip *chip)
 115 {
 116         int ret;
 117
 118         ret = lp55xx_write(chip, LP5523_REG_ENABLE, LP5523_ENABLE);
 119         if (ret)
 120                 return ret;
 121
 122         /* Chip startup time is 500 us, 1 - 2 ms gives some margin */
 123         usleep_range(1000, 2000);
 124
 125         ret = lp55xx_write(chip, LP5523_REG_CONFIG,
 126                             LP5523_AUTO_INC | LP5523_PWR_SAVE |
 127                             LP5523_CP_AUTO | LP5523_AUTO_CLK |
 128                             LP5523_PWM_PWR_SAVE);
 129         if (ret)
 130                 return ret;
 131
 132         /* turn on all leds */
 133         ret = lp55xx_write(chip, LP5523_REG_ENABLE_LEDS_MSB, 0x01);
 134         if (ret)
 135                 return ret;
 136
 137         return lp55xx_write(chip, LP5523_REG_ENABLE_LEDS_LSB, 0xff);
 138 }
 139
 140 static void lp5523_load_engine(struct lp55xx_chip *chip)
 141 {
 142         enum lp55xx_engine_index idx = chip->engine_idx;
 143         u8 mask[] = {
 144                 [LP55XX_ENGINE_1] = LP5523_MODE_ENG1_M,
 145                 [LP55XX_ENGINE_2] = LP5523_MODE_ENG2_M,
 146                 [LP55XX_ENGINE_3] = LP5523_MODE_ENG3_M,
 147         };
 148
 149         u8 val[] = {
 150                 [LP55XX_ENGINE_1] = LP5523_LOAD_ENG1,
 151                 [LP55XX_ENGINE_2] = LP5523_LOAD_ENG2,
 152                 [LP55XX_ENGINE_3] = LP5523_LOAD_ENG3,
 153         };
 154
 155         lp55xx_update_bits(chip, LP5523_REG_OP_MODE, mask[idx], val[idx]);
 156
 157         lp5523_wait_opmode_done();
 158 }
 159
 160 static void lp5523_load_engine_and_select_page(struct lp55xx_chip *chip)
 161 {
 162         enum lp55xx_engine_index idx = chip->engine_idx;
 163         u8 page_sel[] = {
 164                 [LP55XX_ENGINE_1] = LP5523_PAGE_ENG1,
 165                 [LP55XX_ENGINE_2] = LP5523_PAGE_ENG2,
 166                 [LP55XX_ENGINE_3] = LP5523_PAGE_ENG3,
 167         };
 168
 169         lp5523_load_engine(chip);
 170
 171         lp55xx_write(chip, LP5523_REG_PROG_PAGE_SEL, page_sel[idx]);
 172 }
 173
 174 static void lp5523_stop_engine(struct lp55xx_chip *chip)
 175 {
 176         lp55xx_write(chip, LP5523_REG_OP_MODE, 0);
 177         lp5523_wait_opmode_done();
 178 }
 179
 180 static void lp5523_turn_off_channels(struct lp55xx_chip *chip)
 181 {
 182         int i;
 183
 184         for (i = 0; i < LP5523_MAX_LEDS; i++)
 185                 lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0);
 186 }
 187
 188 static void lp5523_run_engine(struct lp55xx_chip *chip, bool start)
 189 {
 190         int ret;
 191         u8 mode;
 192         u8 exec;
 193
 194         /* stop engine */
 195         if (!start) {
 196                 lp5523_stop_engine(chip);
 197                 lp5523_turn_off_channels(chip);
 198                 return;
 199         }
 200
 201         /*
 202          * To run the engine,
 203          * operation mode and enable register should updated at the same time
 204          */
 205
 206         ret = lp55xx_read(chip, LP5523_REG_OP_MODE, &mode);
 207         if (ret)
 208                 return;
 209
 210         ret = lp55xx_read(chip, LP5523_REG_ENABLE, &exec);
 211         if (ret)
 212                 return;
 213
 214         /* change operation mode to RUN only when each engine is loading */
 215         if (LP5523_ENG1_IS_LOADING(mode)) {
 216                 mode = (mode & ~LP5523_MODE_ENG1_M) | LP5523_RUN_ENG1;
 217                 exec = (exec & ~LP5523_EXEC_ENG1_M) | LP5523_RUN_ENG1;
 218         }
 219
 220         if (LP5523_ENG2_IS_LOADING(mode)) {
 221                 mode = (mode & ~LP5523_MODE_ENG2_M) | LP5523_RUN_ENG2;
 222                 exec = (exec & ~LP5523_EXEC_ENG2_M) | LP5523_RUN_ENG2;
 223         }
 224
 225         if (LP5523_ENG3_IS_LOADING(mode)) {
 226                 mode = (mode & ~LP5523_MODE_ENG3_M) | LP5523_RUN_ENG3;
 227                 exec = (exec & ~LP5523_EXEC_ENG3_M) | LP5523_RUN_ENG3;
 228         }
 229
 230         lp55xx_write(chip, LP5523_REG_OP_MODE, mode);
 231         lp5523_wait_opmode_done();
 232
 233         lp55xx_update_bits(chip, LP5523_REG_ENABLE, LP5523_EXEC_M, exec);
 234 }
 235
 236 static int lp5523_update_program_memory(struct lp55xx_chip *chip,
 237                                         const u8 *data, size_t size)
 238 {
 239         u8 pattern[LP5523_PROGRAM_LENGTH] = {0};
 240         unsigned cmd;
 241         char c[3];
 242         int update_size;
 243         int nrchars;
 244         int offset = 0;
 245         int ret;
 246         int i;
 247
 248         /* clear program memory before updating */
 249         for (i = 0; i < LP5523_PROGRAM_LENGTH; i++)
 250                 lp55xx_write(chip, LP5523_REG_PROG_MEM + i, 0);
 251
 252         i = 0;
 253         while ((offset < size - 1) && (i < LP5523_PROGRAM_LENGTH)) {
 254                 /* separate sscanfs because length is working only for %s */
 255                 ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
 256                 if (ret != 1)
 257                         goto err;
 258
 259                 ret = sscanf(c, "%2x", &cmd);
 260                 if (ret != 1)
 261                         goto err;
 262
 263                 pattern[i] = (u8)cmd;
 264                 offset += nrchars;
 265                 i++;
 266         }
 267
 268         /* Each instruction is 16bit long. Check that length is even */
 269         if (i % 2)
 270                 goto err;
 271
 272         update_size = i;
 273         for (i = 0; i < update_size; i++)
 274                 lp55xx_write(chip, LP5523_REG_PROG_MEM + i, pattern[i]);
 275
 276         return 0;
 277
 278 err:
 279         dev_err(&chip->cl->dev, "wrong pattern format\n");
 280         return -EINVAL;
 281 }
 282
 283 static void lp5523_firmware_loaded(struct lp55xx_chip *chip)
 284 {
 285         const struct firmware *fw = chip->fw;
 286
 287         if (fw->size > LP5523_PROGRAM_LENGTH) {
 288                 dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
 289                         fw->size);
 290                 return;
 291         }
 292
 293         /*
 294          * Program momery sequence
 295          *  1) set engine mode to "LOAD"
 296          *  2) write firmware data into program memory
 297          */
 298
 299         lp5523_load_engine_and_select_page(chip);
 300         lp5523_update_program_memory(chip, fw->data, fw->size);
 301 }
 302
 303 static ssize_t lp5523_selftest(struct device *dev,
 304                                struct device_attribute *attr,
 305                                char *buf)
 306 {
 307         struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
 308         struct lp55xx_chip *chip = led->chip;
 309         struct lp55xx_platform_data *pdata = chip->pdata;
 310         int i, ret, pos = 0;
 311         u8 status, adc, vdd;
 312
 313         mutex_lock(&chip->lock);
 314
 315         ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
 316         if (ret < 0)
 317                 goto fail;
 318
 319         /* Check that ext clock is really in use if requested */
 320         if (pdata->clock_mode == LP55XX_CLOCK_EXT) {
 321                 if  ((status & LP5523_EXT_CLK_USED) == 0)
 322                         goto fail;
 323         }
 324
 325         /* Measure VDD (i.e. VBAT) first (channel 16 corresponds to VDD) */
 326         lp55xx_write(chip, LP5523_REG_LED_TEST_CTRL, LP5523_EN_LEDTEST | 16);
 327         usleep_range(3000, 6000); /* ADC conversion time is typically 2.7 ms */
 328         ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
 329         if (ret < 0)
 330                 goto fail;
 331
 332         if (!(status & LP5523_LEDTEST_DONE))
 333                 usleep_range(3000, 6000); /* Was not ready. Wait little bit */
 334
 335         ret = lp55xx_read(chip, LP5523_REG_LED_TEST_ADC, &vdd);
 336         if (ret < 0)
 337                 goto fail;
 338
 339         vdd--;  /* There may be some fluctuation in measurement */
 340
 341         for (i = 0; i < LP5523_MAX_LEDS; i++) {
 342                 /* Skip non-existing channels */
 343                 if (pdata->led_config[i].led_current == 0)
 344                         continue;
 345
 346                 /* Set default current */
 347                 lp55xx_write(chip, LP5523_REG_LED_CURRENT_BASE + i,
 348                         pdata->led_config[i].led_current);
 349
 350                 lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0xff);
 351                 /* let current stabilize 2 - 4ms before measurements start */
 352                 usleep_range(2000, 4000);
 353                 lp55xx_write(chip, LP5523_REG_LED_TEST_CTRL,
 354                              LP5523_EN_LEDTEST | i);
 355                 /* ADC conversion time is 2.7 ms typically */
 356                 usleep_range(3000, 6000);
 357                 ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
 358                 if (ret < 0)
 359                         goto fail;
 360
 361                 if (!(status & LP5523_LEDTEST_DONE))
 362                         usleep_range(3000, 6000);/* Was not ready. Wait. */
 363
 364                 ret = lp55xx_read(chip, LP5523_REG_LED_TEST_ADC, &adc);
 365                 if (ret < 0)
 366                         goto fail;
 367
 368                 if (adc >= vdd || adc < LP5523_ADC_SHORTCIRC_LIM)
 369                         pos += sprintf(buf + pos, "LED %d FAIL\n", i);
 370
 371                 lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0x00);
 372
 373                 /* Restore current */
 374                 lp55xx_write(chip, LP5523_REG_LED_CURRENT_BASE + i,
 375                         led->led_current);
 376                 led++;
 377         }
 378         if (pos == 0)
 379                 pos = sprintf(buf, "OK\n");
 380         goto release_lock;
 381 fail:
 382         pos = sprintf(buf, "FAIL\n");
 383
 384 release_lock:
 385         mutex_unlock(&chip->lock);
 386
 387         return pos;
 388 }
 389
 390 static void lp5523_led_brightness_work(struct work_struct *work)
 391 {
 392         struct lp55xx_led *led = container_of(work, struct lp55xx_led,
 393                                               brightness_work);
 394         struct lp55xx_chip *chip = led->chip;
 395
 396         mutex_lock(&chip->lock);
 397         lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + led->chan_nr,
 398                      led->brightness);
 399         mutex_unlock(&chip->lock);
 400 }
 401
 402 static DEVICE_ATTR(selftest, S_IRUGO, lp5523_selftest, NULL);
 403
 404 static struct attribute *lp5523_attributes[] = {
 405         &dev_attr_selftest.attr,
 406         NULL,
 407 };
 408
 409 static const struct attribute_group lp5523_group = {
 410         .attrs = lp5523_attributes,
 411 };
 412
 413 /* Chip specific configurations */
 414 static struct lp55xx_device_config lp5523_cfg = {
 415         .reset = {
 416                 .addr = LP5523_REG_RESET,
 417                 .val  = LP5523_RESET,
 418         },
 419         .enable = {
 420                 .addr = LP5523_REG_ENABLE,
 421                 .val  = LP5523_ENABLE,
 422         },
 423         .max_channel  = LP5523_MAX_LEDS,
 424         .post_init_device   = lp5523_post_init_device,
 425         .brightness_work_fn = lp5523_led_brightness_work,
 426         .set_led_current    = lp5523_set_led_current,
 427         .firmware_cb        = lp5523_firmware_loaded,
 428         .run_engine         = lp5523_run_engine,
 429         .dev_attr_group     = &lp5523_group,
 430 };
 431
 432 static int lp5523_probe(struct i2c_client *client,
 433                         const struct i2c_device_id *id)
 434 {
 435         int ret;
 436         struct lp55xx_chip *chip;
 437         struct lp55xx_led *led;
 438         struct lp55xx_platform_data *pdata;
 439         struct device_node *np = client->dev.of_node;
 440
 441         if (!dev_get_platdata(&client->dev)) {
 442                 if (np) {
 443                         ret = lp55xx_of_populate_pdata(&client->dev, np);
 444                         if (ret < 0)
 445                                 return ret;
 446                 } else {
 447                         dev_err(&client->dev, "no platform data\n");
 448                         return -EINVAL;
 449                 }
 450         }
 451         pdata = dev_get_platdata(&client->dev);
 452
 453         chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
 454         if (!chip)
 455                 return -ENOMEM;
 456
 457         led = devm_kzalloc(&client->dev,
 458                         sizeof(*led) * pdata->num_channels, GFP_KERNEL);
 459         if (!led)
 460                 return -ENOMEM;
 461
 462         chip->cl = client;
 463         chip->pdata = pdata;
 464         chip->cfg = &lp5523_cfg;
 465
 466         mutex_init(&chip->lock);
 467
 468         i2c_set_clientdata(client, led);
 469
 470         ret = lp55xx_init_device(chip);
 471         if (ret)
 472                 goto err_init;
 473
 474         dev_info(&client->dev, "%s Programmable led chip found\n", id->name);
 475
 476         ret = lp55xx_register_leds(led, chip);
 477         if (ret)
 478                 goto err_register_leds;
 479
 480         ret = lp55xx_register_sysfs(chip);
 481         if (ret) {
 482                 dev_err(&client->dev, "registering sysfs failed\n");
 483                 goto err_register_sysfs;
 484         }
 485
 486         return 0;
 487
 488 err_register_sysfs:
 489         lp55xx_unregister_leds(led, chip);
 490 err_register_leds:
 491         lp55xx_deinit_device(chip);
 492 err_init:
 493         return ret;
 494 }
 495
 496 static int lp5523_remove(struct i2c_client *client)
 497 {
 498         struct lp55xx_led *led = i2c_get_clientdata(client);
 499         struct lp55xx_chip *chip = led->chip;
 500
 501         lp5523_stop_engine(chip);
 502         lp55xx_unregister_sysfs(chip);
 503         lp55xx_unregister_leds(led, chip);
 504         lp55xx_deinit_device(chip);
 505
 506         return 0;
 507 }
 508
 509 static const struct i2c_device_id lp5523_id[] = {
 510         { "lp5523",  LP5523 },
 511         { "lp55231", LP55231 },
 512         { }
 513 };
 514
 515 MODULE_DEVICE_TABLE(i2c, lp5523_id);
 516
 517 #ifdef CONFIG_OF
 518 static const struct of_device_id of_lp5523_leds_match[] = {
 519         { .compatible = "national,lp5523", },
 520         {},
 521 };
 522
 523 MODULE_DEVICE_TABLE(of, of_lp5523_leds_match);
 524 #endif
 525
 526 static struct i2c_driver lp5523_driver = {
 527         .driver = {
 528                 .name   = "lp5523x",
 529                 .of_match_table = of_match_ptr(of_lp5523_leds_match),
 530         },
 531         .probe          = lp5523_probe,
 532         .remove         = lp5523_remove,
 533         .id_table       = lp5523_id,
 534 };
 535
 536 module_i2c_driver(lp5523_driver);
 537
 538 MODULE_AUTHOR("Mathias Nyman <mathias.nyman@nokia.com>");
 539 MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
 540 MODULE_DESCRIPTION("LP5523 LED engine");
 541 MODULE_LICENSE("GPL");