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         u8 page_sel[] = {
 156                 [LP55XX_ENGINE_1] = LP5523_PAGE_ENG1,
 157                 [LP55XX_ENGINE_2] = LP5523_PAGE_ENG2,
 158                 [LP55XX_ENGINE_3] = LP5523_PAGE_ENG3,
 159         };
 160
 161         lp55xx_update_bits(chip, LP5523_REG_OP_MODE, mask[idx], val[idx]);
 162
 163         lp5523_wait_opmode_done();
 164
 165         lp55xx_write(chip, LP5523_REG_PROG_PAGE_SEL, page_sel[idx]);
 166 }
 167
 168 static void lp5523_stop_engine(struct lp55xx_chip *chip)
 169 {
 170         lp55xx_write(chip, LP5523_REG_OP_MODE, 0);
 171         lp5523_wait_opmode_done();
 172 }
 173
 174 static void lp5523_turn_off_channels(struct lp55xx_chip *chip)
 175 {
 176         int i;
 177
 178         for (i = 0; i < LP5523_MAX_LEDS; i++)
 179                 lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0);
 180 }
 181
 182 static void lp5523_run_engine(struct lp55xx_chip *chip, bool start)
 183 {
 184         int ret;
 185         u8 mode;
 186         u8 exec;
 187
 188         /* stop engine */
 189         if (!start) {
 190                 lp5523_stop_engine(chip);
 191                 lp5523_turn_off_channels(chip);
 192                 return;
 193         }
 194
 195         /*
 196          * To run the engine,
 197          * operation mode and enable register should updated at the same time
 198          */
 199
 200         ret = lp55xx_read(chip, LP5523_REG_OP_MODE, &mode);
 201         if (ret)
 202                 return;
 203
 204         ret = lp55xx_read(chip, LP5523_REG_ENABLE, &exec);
 205         if (ret)
 206                 return;
 207
 208         /* change operation mode to RUN only when each engine is loading */
 209         if (LP5523_ENG1_IS_LOADING(mode)) {
 210                 mode = (mode & ~LP5523_MODE_ENG1_M) | LP5523_RUN_ENG1;
 211                 exec = (exec & ~LP5523_EXEC_ENG1_M) | LP5523_RUN_ENG1;
 212         }
 213
 214         if (LP5523_ENG2_IS_LOADING(mode)) {
 215                 mode = (mode & ~LP5523_MODE_ENG2_M) | LP5523_RUN_ENG2;
 216                 exec = (exec & ~LP5523_EXEC_ENG2_M) | LP5523_RUN_ENG2;
 217         }
 218
 219         if (LP5523_ENG3_IS_LOADING(mode)) {
 220                 mode = (mode & ~LP5523_MODE_ENG3_M) | LP5523_RUN_ENG3;
 221                 exec = (exec & ~LP5523_EXEC_ENG3_M) | LP5523_RUN_ENG3;
 222         }
 223
 224         lp55xx_write(chip, LP5523_REG_OP_MODE, mode);
 225         lp5523_wait_opmode_done();
 226
 227         lp55xx_update_bits(chip, LP5523_REG_ENABLE, LP5523_EXEC_M, exec);
 228 }
 229
 230 static int lp5523_update_program_memory(struct lp55xx_chip *chip,
 231                                         const u8 *data, size_t size)
 232 {
 233         u8 pattern[LP5523_PROGRAM_LENGTH] = {0};
 234         unsigned cmd;
 235         char c[3];
 236         int update_size;
 237         int nrchars;
 238         int offset = 0;
 239         int ret;
 240         int i;
 241
 242         /* clear program memory before updating */
 243         for (i = 0; i < LP5523_PROGRAM_LENGTH; i++)
 244                 lp55xx_write(chip, LP5523_REG_PROG_MEM + i, 0);
 245
 246         i = 0;
 247         while ((offset < size - 1) && (i < LP5523_PROGRAM_LENGTH)) {
 248                 /* separate sscanfs because length is working only for %s */
 249                 ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
 250                 if (ret != 1)
 251                         goto err;
 252
 253                 ret = sscanf(c, "%2x", &cmd);
 254                 if (ret != 1)
 255                         goto err;
 256
 257                 pattern[i] = (u8)cmd;
 258                 offset += nrchars;
 259                 i++;
 260         }
 261
 262         /* Each instruction is 16bit long. Check that length is even */
 263         if (i % 2)
 264                 goto err;
 265
 266         update_size = i;
 267         for (i = 0; i < update_size; i++)
 268                 lp55xx_write(chip, LP5523_REG_PROG_MEM + i, pattern[i]);
 269
 270         return 0;
 271
 272 err:
 273         dev_err(&chip->cl->dev, "wrong pattern format\n");
 274         return -EINVAL;
 275 }
 276
 277 static void lp5523_firmware_loaded(struct lp55xx_chip *chip)
 278 {
 279         const struct firmware *fw = chip->fw;
 280
 281         if (fw->size > LP5523_PROGRAM_LENGTH) {
 282                 dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
 283                         fw->size);
 284                 return;
 285         }
 286
 287         /*
 288          * Program momery sequence
 289          *  1) set engine mode to "LOAD"
 290          *  2) write firmware data into program memory
 291          */
 292
 293         lp5523_load_engine(chip);
 294         lp5523_update_program_memory(chip, fw->data, fw->size);
 295 }
 296
 297 static ssize_t lp5523_selftest(struct device *dev,
 298                                struct device_attribute *attr,
 299                                char *buf)
 300 {
 301         struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
 302         struct lp55xx_chip *chip = led->chip;
 303         struct lp55xx_platform_data *pdata = chip->pdata;
 304         int i, ret, pos = 0;
 305         u8 status, adc, vdd;
 306
 307         mutex_lock(&chip->lock);
 308
 309         ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
 310         if (ret < 0)
 311                 goto fail;
 312
 313         /* Check that ext clock is really in use if requested */
 314         if (pdata->clock_mode == LP55XX_CLOCK_EXT) {
 315                 if  ((status & LP5523_EXT_CLK_USED) == 0)
 316                         goto fail;
 317         }
 318
 319         /* Measure VDD (i.e. VBAT) first (channel 16 corresponds to VDD) */
 320         lp55xx_write(chip, LP5523_REG_LED_TEST_CTRL, LP5523_EN_LEDTEST | 16);
 321         usleep_range(3000, 6000); /* ADC conversion time is typically 2.7 ms */
 322         ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
 323         if (ret < 0)
 324                 goto fail;
 325
 326         if (!(status & LP5523_LEDTEST_DONE))
 327                 usleep_range(3000, 6000); /* Was not ready. Wait little bit */
 328
 329         ret = lp55xx_read(chip, LP5523_REG_LED_TEST_ADC, &vdd);
 330         if (ret < 0)
 331                 goto fail;
 332
 333         vdd--;  /* There may be some fluctuation in measurement */
 334
 335         for (i = 0; i < LP5523_MAX_LEDS; i++) {
 336                 /* Skip non-existing channels */
 337                 if (pdata->led_config[i].led_current == 0)
 338                         continue;
 339
 340                 /* Set default current */
 341                 lp55xx_write(chip, LP5523_REG_LED_CURRENT_BASE + i,
 342                         pdata->led_config[i].led_current);
 343
 344                 lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0xff);
 345                 /* let current stabilize 2 - 4ms before measurements start */
 346                 usleep_range(2000, 4000);
 347                 lp55xx_write(chip, LP5523_REG_LED_TEST_CTRL,
 348                              LP5523_EN_LEDTEST | i);
 349                 /* ADC conversion time is 2.7 ms typically */
 350                 usleep_range(3000, 6000);
 351                 ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
 352                 if (ret < 0)
 353                         goto fail;
 354
 355                 if (!(status & LP5523_LEDTEST_DONE))
 356                         usleep_range(3000, 6000);/* Was not ready. Wait. */
 357
 358                 ret = lp55xx_read(chip, LP5523_REG_LED_TEST_ADC, &adc);
 359                 if (ret < 0)
 360                         goto fail;
 361
 362                 if (adc >= vdd || adc < LP5523_ADC_SHORTCIRC_LIM)
 363                         pos += sprintf(buf + pos, "LED %d FAIL\n", i);
 364
 365                 lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0x00);
 366
 367                 /* Restore current */
 368                 lp55xx_write(chip, LP5523_REG_LED_CURRENT_BASE + i,
 369                         led->led_current);
 370                 led++;
 371         }
 372         if (pos == 0)
 373                 pos = sprintf(buf, "OK\n");
 374         goto release_lock;
 375 fail:
 376         pos = sprintf(buf, "FAIL\n");
 377
 378 release_lock:
 379         mutex_unlock(&chip->lock);
 380
 381         return pos;
 382 }
 383
 384 static void lp5523_led_brightness_work(struct work_struct *work)
 385 {
 386         struct lp55xx_led *led = container_of(work, struct lp55xx_led,
 387                                               brightness_work);
 388         struct lp55xx_chip *chip = led->chip;
 389
 390         mutex_lock(&chip->lock);
 391         lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + led->chan_nr,
 392                      led->brightness);
 393         mutex_unlock(&chip->lock);
 394 }
 395
 396 static DEVICE_ATTR(selftest, S_IRUGO, lp5523_selftest, NULL);
 397
 398 static struct attribute *lp5523_attributes[] = {
 399         &dev_attr_selftest.attr,
 400         NULL,
 401 };
 402
 403 static const struct attribute_group lp5523_group = {
 404         .attrs = lp5523_attributes,
 405 };
 406
 407 /* Chip specific configurations */
 408 static struct lp55xx_device_config lp5523_cfg = {
 409         .reset = {
 410                 .addr = LP5523_REG_RESET,
 411                 .val  = LP5523_RESET,
 412         },
 413         .enable = {
 414                 .addr = LP5523_REG_ENABLE,
 415                 .val  = LP5523_ENABLE,
 416         },
 417         .max_channel  = LP5523_MAX_LEDS,
 418         .post_init_device   = lp5523_post_init_device,
 419         .brightness_work_fn = lp5523_led_brightness_work,
 420         .set_led_current    = lp5523_set_led_current,
 421         .firmware_cb        = lp5523_firmware_loaded,
 422         .run_engine         = lp5523_run_engine,
 423         .dev_attr_group     = &lp5523_group,
 424 };
 425
 426 static int lp5523_probe(struct i2c_client *client,
 427                         const struct i2c_device_id *id)
 428 {
 429         int ret;
 430         struct lp55xx_chip *chip;
 431         struct lp55xx_led *led;
 432         struct lp55xx_platform_data *pdata = client->dev.platform_data;
 433
 434         if (!pdata) {
 435                 dev_err(&client->dev, "no platform data\n");
 436                 return -EINVAL;
 437         }
 438
 439         chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
 440         if (!chip)
 441                 return -ENOMEM;
 442
 443         led = devm_kzalloc(&client->dev,
 444                         sizeof(*led) * pdata->num_channels, GFP_KERNEL);
 445         if (!led)
 446                 return -ENOMEM;
 447
 448         chip->cl = client;
 449         chip->pdata = pdata;
 450         chip->cfg = &lp5523_cfg;
 451
 452         mutex_init(&chip->lock);
 453
 454         i2c_set_clientdata(client, led);
 455
 456         ret = lp55xx_init_device(chip);
 457         if (ret)
 458                 goto err_init;
 459
 460         dev_info(&client->dev, "%s Programmable led chip found\n", id->name);
 461
 462         ret = lp55xx_register_leds(led, chip);
 463         if (ret)
 464                 goto err_register_leds;
 465
 466         ret = lp55xx_register_sysfs(chip);
 467         if (ret) {
 468                 dev_err(&client->dev, "registering sysfs failed\n");
 469                 goto err_register_sysfs;
 470         }
 471
 472         return 0;
 473
 474 err_register_sysfs:
 475         lp55xx_unregister_leds(led, chip);
 476 err_register_leds:
 477         lp55xx_deinit_device(chip);
 478 err_init:
 479         return ret;
 480 }
 481
 482 static int lp5523_remove(struct i2c_client *client)
 483 {
 484         struct lp55xx_led *led = i2c_get_clientdata(client);
 485         struct lp55xx_chip *chip = led->chip;
 486
 487         lp5523_stop_engine(chip);
 488         lp55xx_unregister_sysfs(chip);
 489         lp55xx_unregister_leds(led, chip);
 490         lp55xx_deinit_device(chip);
 491
 492         return 0;
 493 }
 494
 495 static const struct i2c_device_id lp5523_id[] = {
 496         { "lp5523",  LP5523 },
 497         { "lp55231", LP55231 },
 498         { }
 499 };
 500
 501 MODULE_DEVICE_TABLE(i2c, lp5523_id);
 502
 503 static struct i2c_driver lp5523_driver = {
 504         .driver = {
 505                 .name   = "lp5523x",
 506         },
 507         .probe          = lp5523_probe,
 508         .remove         = lp5523_remove,
 509         .id_table       = lp5523_id,
 510 };
 511
 512 module_i2c_driver(lp5523_driver);
 513
 514 MODULE_AUTHOR("Mathias Nyman <mathias.nyman@nokia.com>");
 515 MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
 516 MODULE_DESCRIPTION("LP5523 LED engine");
 517 MODULE_LICENSE("GPL");