linux/drivers/leds/leds-lp5562.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * LP5562 LED driver
   4 *
   5 * Copyright (C) 2013 Texas Instruments
   6 *
   7 * Author: Milo(Woogyom) Kim <milo.kim@ti.com>
   8 */
   9
  10#include <linux/delay.h>
  11#include <linux/firmware.h>
  12#include <linux/i2c.h>
  13#include <linux/leds.h>
  14#include <linux/module.h>
  15#include <linux/mutex.h>
  16#include <linux/of.h>
  17#include <linux/platform_data/leds-lp55xx.h>
  18#include <linux/slab.h>
  19
  20#include "leds-lp55xx-common.h"
  21
  22#define LP5562_PROGRAM_LENGTH           32
  23#define LP5562_MAX_LEDS                 4
  24
  25/* ENABLE Register 00h */
  26#define LP5562_REG_ENABLE               0x00
  27#define LP5562_EXEC_ENG1_M              0x30
  28#define LP5562_EXEC_ENG2_M              0x0C
  29#define LP5562_EXEC_ENG3_M              0x03
  30#define LP5562_EXEC_M                   0x3F
  31#define LP5562_MASTER_ENABLE            0x40    /* Chip master enable */
  32#define LP5562_LOGARITHMIC_PWM          0x80    /* Logarithmic PWM adjustment */
  33#define LP5562_EXEC_RUN                 0x2A
  34#define LP5562_ENABLE_DEFAULT   \
  35        (LP5562_MASTER_ENABLE | LP5562_LOGARITHMIC_PWM)
  36#define LP5562_ENABLE_RUN_PROGRAM       \
  37        (LP5562_ENABLE_DEFAULT | LP5562_EXEC_RUN)
  38
  39/* OPMODE Register 01h */
  40#define LP5562_REG_OP_MODE              0x01
  41#define LP5562_MODE_ENG1_M              0x30
  42#define LP5562_MODE_ENG2_M              0x0C
  43#define LP5562_MODE_ENG3_M              0x03
  44#define LP5562_LOAD_ENG1                0x10
  45#define LP5562_LOAD_ENG2                0x04
  46#define LP5562_LOAD_ENG3                0x01
  47#define LP5562_RUN_ENG1                 0x20
  48#define LP5562_RUN_ENG2                 0x08
  49#define LP5562_RUN_ENG3                 0x02
  50#define LP5562_ENG1_IS_LOADING(mode)    \
  51        ((mode & LP5562_MODE_ENG1_M) == LP5562_LOAD_ENG1)
  52#define LP5562_ENG2_IS_LOADING(mode)    \
  53        ((mode & LP5562_MODE_ENG2_M) == LP5562_LOAD_ENG2)
  54#define LP5562_ENG3_IS_LOADING(mode)    \
  55        ((mode & LP5562_MODE_ENG3_M) == LP5562_LOAD_ENG3)
  56
  57/* BRIGHTNESS Registers */
  58#define LP5562_REG_R_PWM                0x04
  59#define LP5562_REG_G_PWM                0x03
  60#define LP5562_REG_B_PWM                0x02
  61#define LP5562_REG_W_PWM                0x0E
  62
  63/* CURRENT Registers */
  64#define LP5562_REG_R_CURRENT            0x07
  65#define LP5562_REG_G_CURRENT            0x06
  66#define LP5562_REG_B_CURRENT            0x05
  67#define LP5562_REG_W_CURRENT            0x0F
  68
  69/* CONFIG Register 08h */
  70#define LP5562_REG_CONFIG               0x08
  71#define LP5562_PWM_HF                   0x40
  72#define LP5562_PWRSAVE_EN               0x20
  73#define LP5562_CLK_INT                  0x01    /* Internal clock */
  74#define LP5562_DEFAULT_CFG              (LP5562_PWM_HF | LP5562_PWRSAVE_EN)
  75
  76/* RESET Register 0Dh */
  77#define LP5562_REG_RESET                0x0D
  78#define LP5562_RESET                    0xFF
  79
  80/* PROGRAM ENGINE Registers */
  81#define LP5562_REG_PROG_MEM_ENG1        0x10
  82#define LP5562_REG_PROG_MEM_ENG2        0x30
  83#define LP5562_REG_PROG_MEM_ENG3        0x50
  84
  85/* LEDMAP Register 70h */
  86#define LP5562_REG_ENG_SEL              0x70
  87#define LP5562_ENG_SEL_PWM              0
  88#define LP5562_ENG_FOR_RGB_M            0x3F
  89#define LP5562_ENG_SEL_RGB              0x1B    /* R:ENG1, G:ENG2, B:ENG3 */
  90#define LP5562_ENG_FOR_W_M              0xC0
  91#define LP5562_ENG1_FOR_W               0x40    /* W:ENG1 */
  92#define LP5562_ENG2_FOR_W               0x80    /* W:ENG2 */
  93#define LP5562_ENG3_FOR_W               0xC0    /* W:ENG3 */
  94
  95/* Program Commands */
  96#define LP5562_CMD_DISABLE              0x00
  97#define LP5562_CMD_LOAD                 0x15
  98#define LP5562_CMD_RUN                  0x2A
  99#define LP5562_CMD_DIRECT               0x3F
 100#define LP5562_PATTERN_OFF              0
 101
 102static inline void lp5562_wait_opmode_done(void)
 103{
 104        /* operation mode change needs to be longer than 153 us */
 105        usleep_range(200, 300);
 106}
 107
 108static inline void lp5562_wait_enable_done(void)
 109{
 110        /* it takes more 488 us to update ENABLE register */
 111        usleep_range(500, 600);
 112}
 113
 114static void lp5562_set_led_current(struct lp55xx_led *led, u8 led_current)
 115{
 116        static const u8 addr[] = {
 117                LP5562_REG_R_CURRENT,
 118                LP5562_REG_G_CURRENT,
 119                LP5562_REG_B_CURRENT,
 120                LP5562_REG_W_CURRENT,
 121        };
 122
 123        led->led_current = led_current;
 124        lp55xx_write(led->chip, addr[led->chan_nr], led_current);
 125}
 126
 127static void lp5562_load_engine(struct lp55xx_chip *chip)
 128{
 129        enum lp55xx_engine_index idx = chip->engine_idx;
 130        static const u8 mask[] = {
 131                [LP55XX_ENGINE_1] = LP5562_MODE_ENG1_M,
 132                [LP55XX_ENGINE_2] = LP5562_MODE_ENG2_M,
 133                [LP55XX_ENGINE_3] = LP5562_MODE_ENG3_M,
 134        };
 135
 136        static const u8 val[] = {
 137                [LP55XX_ENGINE_1] = LP5562_LOAD_ENG1,
 138                [LP55XX_ENGINE_2] = LP5562_LOAD_ENG2,
 139                [LP55XX_ENGINE_3] = LP5562_LOAD_ENG3,
 140        };
 141
 142        lp55xx_update_bits(chip, LP5562_REG_OP_MODE, mask[idx], val[idx]);
 143
 144        lp5562_wait_opmode_done();
 145}
 146
 147static void lp5562_stop_engine(struct lp55xx_chip *chip)
 148{
 149        lp55xx_write(chip, LP5562_REG_OP_MODE, LP5562_CMD_DISABLE);
 150        lp5562_wait_opmode_done();
 151}
 152
 153static void lp5562_run_engine(struct lp55xx_chip *chip, bool start)
 154{
 155        int ret;
 156        u8 mode;
 157        u8 exec;
 158
 159        /* stop engine */
 160        if (!start) {
 161                lp55xx_write(chip, LP5562_REG_ENABLE, LP5562_ENABLE_DEFAULT);
 162                lp5562_wait_enable_done();
 163                lp5562_stop_engine(chip);
 164                lp55xx_write(chip, LP5562_REG_ENG_SEL, LP5562_ENG_SEL_PWM);
 165                lp55xx_write(chip, LP5562_REG_OP_MODE, LP5562_CMD_DIRECT);
 166                lp5562_wait_opmode_done();
 167                return;
 168        }
 169
 170        /*
 171         * To run the engine,
 172         * operation mode and enable register should updated at the same time
 173         */
 174
 175        ret = lp55xx_read(chip, LP5562_REG_OP_MODE, &mode);
 176        if (ret)
 177                return;
 178
 179        ret = lp55xx_read(chip, LP5562_REG_ENABLE, &exec);
 180        if (ret)
 181                return;
 182
 183        /* change operation mode to RUN only when each engine is loading */
 184        if (LP5562_ENG1_IS_LOADING(mode)) {
 185                mode = (mode & ~LP5562_MODE_ENG1_M) | LP5562_RUN_ENG1;
 186                exec = (exec & ~LP5562_EXEC_ENG1_M) | LP5562_RUN_ENG1;
 187        }
 188
 189        if (LP5562_ENG2_IS_LOADING(mode)) {
 190                mode = (mode & ~LP5562_MODE_ENG2_M) | LP5562_RUN_ENG2;
 191                exec = (exec & ~LP5562_EXEC_ENG2_M) | LP5562_RUN_ENG2;
 192        }
 193
 194        if (LP5562_ENG3_IS_LOADING(mode)) {
 195                mode = (mode & ~LP5562_MODE_ENG3_M) | LP5562_RUN_ENG3;
 196                exec = (exec & ~LP5562_EXEC_ENG3_M) | LP5562_RUN_ENG3;
 197        }
 198
 199        lp55xx_write(chip, LP5562_REG_OP_MODE, mode);
 200        lp5562_wait_opmode_done();
 201
 202        lp55xx_update_bits(chip, LP5562_REG_ENABLE, LP5562_EXEC_M, exec);
 203        lp5562_wait_enable_done();
 204}
 205
 206static int lp5562_update_firmware(struct lp55xx_chip *chip,
 207                                        const u8 *data, size_t size)
 208{
 209        enum lp55xx_engine_index idx = chip->engine_idx;
 210        u8 pattern[LP5562_PROGRAM_LENGTH] = {0};
 211        static const u8 addr[] = {
 212                [LP55XX_ENGINE_1] = LP5562_REG_PROG_MEM_ENG1,
 213                [LP55XX_ENGINE_2] = LP5562_REG_PROG_MEM_ENG2,
 214                [LP55XX_ENGINE_3] = LP5562_REG_PROG_MEM_ENG3,
 215        };
 216        unsigned cmd;
 217        char c[3];
 218        int program_size;
 219        int nrchars;
 220        int offset = 0;
 221        int ret;
 222        int i;
 223
 224        /* clear program memory before updating */
 225        for (i = 0; i < LP5562_PROGRAM_LENGTH; i++)
 226                lp55xx_write(chip, addr[idx] + i, 0);
 227
 228        i = 0;
 229        while ((offset < size - 1) && (i < LP5562_PROGRAM_LENGTH)) {
 230                /* separate sscanfs because length is working only for %s */
 231                ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
 232                if (ret != 1)
 233                        goto err;
 234
 235                ret = sscanf(c, "%2x", &cmd);
 236                if (ret != 1)
 237                        goto err;
 238
 239                pattern[i] = (u8)cmd;
 240                offset += nrchars;
 241                i++;
 242        }
 243
 244        /* Each instruction is 16bit long. Check that length is even */
 245        if (i % 2)
 246                goto err;
 247
 248        program_size = i;
 249        for (i = 0; i < program_size; i++)
 250                lp55xx_write(chip, addr[idx] + i, pattern[i]);
 251
 252        return 0;
 253
 254err:
 255        dev_err(&chip->cl->dev, "wrong pattern format\n");
 256        return -EINVAL;
 257}
 258
 259static void lp5562_firmware_loaded(struct lp55xx_chip *chip)
 260{
 261        const struct firmware *fw = chip->fw;
 262
 263        /*
 264         * the firmware is encoded in ascii hex character, with 2 chars
 265         * per byte
 266         */
 267        if (fw->size > (LP5562_PROGRAM_LENGTH * 2)) {
 268                dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
 269                        fw->size);
 270                return;
 271        }
 272
 273        /*
 274         * Program memory sequence
 275         *  1) set engine mode to "LOAD"
 276         *  2) write firmware data into program memory
 277         */
 278
 279        lp5562_load_engine(chip);
 280        lp5562_update_firmware(chip, fw->data, fw->size);
 281}
 282
 283static int lp5562_post_init_device(struct lp55xx_chip *chip)
 284{
 285        int ret;
 286        u8 cfg = LP5562_DEFAULT_CFG;
 287
 288        /* Set all PWMs to direct control mode */
 289        ret = lp55xx_write(chip, LP5562_REG_OP_MODE, LP5562_CMD_DIRECT);
 290        if (ret)
 291                return ret;
 292
 293        lp5562_wait_opmode_done();
 294
 295        /* Update configuration for the clock setting */
 296        if (!lp55xx_is_extclk_used(chip))
 297                cfg |= LP5562_CLK_INT;
 298
 299        ret = lp55xx_write(chip, LP5562_REG_CONFIG, cfg);
 300        if (ret)
 301                return ret;
 302
 303        /* Initialize all channels PWM to zero -> leds off */
 304        lp55xx_write(chip, LP5562_REG_R_PWM, 0);
 305        lp55xx_write(chip, LP5562_REG_G_PWM, 0);
 306        lp55xx_write(chip, LP5562_REG_B_PWM, 0);
 307        lp55xx_write(chip, LP5562_REG_W_PWM, 0);
 308
 309        /* Set LED map as register PWM by default */
 310        lp55xx_write(chip, LP5562_REG_ENG_SEL, LP5562_ENG_SEL_PWM);
 311
 312        return 0;
 313}
 314
 315static int lp5562_led_brightness(struct lp55xx_led *led)
 316{
 317        struct lp55xx_chip *chip = led->chip;
 318        static const u8 addr[] = {
 319                LP5562_REG_R_PWM,
 320                LP5562_REG_G_PWM,
 321                LP5562_REG_B_PWM,
 322                LP5562_REG_W_PWM,
 323        };
 324        int ret;
 325
 326        mutex_lock(&chip->lock);
 327        ret = lp55xx_write(chip, addr[led->chan_nr], led->brightness);
 328        mutex_unlock(&chip->lock);
 329
 330        return ret;
 331}
 332
 333static void lp5562_write_program_memory(struct lp55xx_chip *chip,
 334                                        u8 base, const u8 *rgb, int size)
 335{
 336        int i;
 337
 338        if (!rgb || size <= 0)
 339                return;
 340
 341        for (i = 0; i < size; i++)
 342                lp55xx_write(chip, base + i, *(rgb + i));
 343
 344        lp55xx_write(chip, base + i, 0);
 345        lp55xx_write(chip, base + i + 1, 0);
 346}
 347
 348/* check the size of program count */
 349static inline bool _is_pc_overflow(struct lp55xx_predef_pattern *ptn)
 350{
 351        return ptn->size_r >= LP5562_PROGRAM_LENGTH ||
 352               ptn->size_g >= LP5562_PROGRAM_LENGTH ||
 353               ptn->size_b >= LP5562_PROGRAM_LENGTH;
 354}
 355
 356static int lp5562_run_predef_led_pattern(struct lp55xx_chip *chip, int mode)
 357{
 358        struct lp55xx_predef_pattern *ptn;
 359        int i;
 360
 361        if (mode == LP5562_PATTERN_OFF) {
 362                lp5562_run_engine(chip, false);
 363                return 0;
 364        }
 365
 366        ptn = chip->pdata->patterns + (mode - 1);
 367        if (!ptn || _is_pc_overflow(ptn)) {
 368                dev_err(&chip->cl->dev, "invalid pattern data\n");
 369                return -EINVAL;
 370        }
 371
 372        lp5562_stop_engine(chip);
 373
 374        /* Set LED map as RGB */
 375        lp55xx_write(chip, LP5562_REG_ENG_SEL, LP5562_ENG_SEL_RGB);
 376
 377        /* Load engines */
 378        for (i = LP55XX_ENGINE_1; i <= LP55XX_ENGINE_3; i++) {
 379                chip->engine_idx = i;
 380                lp5562_load_engine(chip);
 381        }
 382
 383        /* Clear program registers */
 384        lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG1, 0);
 385        lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG1 + 1, 0);
 386        lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG2, 0);
 387        lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG2 + 1, 0);
 388        lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG3, 0);
 389        lp55xx_write(chip, LP5562_REG_PROG_MEM_ENG3 + 1, 0);
 390
 391        /* Program engines */
 392        lp5562_write_program_memory(chip, LP5562_REG_PROG_MEM_ENG1,
 393                                ptn->r, ptn->size_r);
 394        lp5562_write_program_memory(chip, LP5562_REG_PROG_MEM_ENG2,
 395                                ptn->g, ptn->size_g);
 396        lp5562_write_program_memory(chip, LP5562_REG_PROG_MEM_ENG3,
 397                                ptn->b, ptn->size_b);
 398
 399        /* Run engines */
 400        lp5562_run_engine(chip, true);
 401
 402        return 0;
 403}
 404
 405static ssize_t lp5562_store_pattern(struct device *dev,
 406                                struct device_attribute *attr,
 407                                const char *buf, size_t len)
 408{
 409        struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
 410        struct lp55xx_chip *chip = led->chip;
 411        struct lp55xx_predef_pattern *ptn = chip->pdata->patterns;
 412        int num_patterns = chip->pdata->num_patterns;
 413        unsigned long mode;
 414        int ret;
 415
 416        ret = kstrtoul(buf, 0, &mode);
 417        if (ret)
 418                return ret;
 419
 420        if (mode > num_patterns || !ptn)
 421                return -EINVAL;
 422
 423        mutex_lock(&chip->lock);
 424        ret = lp5562_run_predef_led_pattern(chip, mode);
 425        mutex_unlock(&chip->lock);
 426
 427        if (ret)
 428                return ret;
 429
 430        return len;
 431}
 432
 433static ssize_t lp5562_store_engine_mux(struct device *dev,
 434                                     struct device_attribute *attr,
 435                                     const char *buf, size_t len)
 436{
 437        struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
 438        struct lp55xx_chip *chip = led->chip;
 439        u8 mask;
 440        u8 val;
 441
 442        /* LED map
 443         * R ... Engine 1 (fixed)
 444         * G ... Engine 2 (fixed)
 445         * B ... Engine 3 (fixed)
 446         * W ... Engine 1 or 2 or 3
 447         */
 448
 449        if (sysfs_streq(buf, "RGB")) {
 450                mask = LP5562_ENG_FOR_RGB_M;
 451                val = LP5562_ENG_SEL_RGB;
 452        } else if (sysfs_streq(buf, "W")) {
 453                enum lp55xx_engine_index idx = chip->engine_idx;
 454
 455                mask = LP5562_ENG_FOR_W_M;
 456                switch (idx) {
 457                case LP55XX_ENGINE_1:
 458                        val = LP5562_ENG1_FOR_W;
 459                        break;
 460                case LP55XX_ENGINE_2:
 461                        val = LP5562_ENG2_FOR_W;
 462                        break;
 463                case LP55XX_ENGINE_3:
 464                        val = LP5562_ENG3_FOR_W;
 465                        break;
 466                default:
 467                        return -EINVAL;
 468                }
 469
 470        } else {
 471                dev_err(dev, "choose RGB or W\n");
 472                return -EINVAL;
 473        }
 474
 475        mutex_lock(&chip->lock);
 476        lp55xx_update_bits(chip, LP5562_REG_ENG_SEL, mask, val);
 477        mutex_unlock(&chip->lock);
 478
 479        return len;
 480}
 481
 482static LP55XX_DEV_ATTR_WO(led_pattern, lp5562_store_pattern);
 483static LP55XX_DEV_ATTR_WO(engine_mux, lp5562_store_engine_mux);
 484
 485static struct attribute *lp5562_attributes[] = {
 486        &dev_attr_led_pattern.attr,
 487        &dev_attr_engine_mux.attr,
 488        NULL,
 489};
 490
 491static const struct attribute_group lp5562_group = {
 492        .attrs = lp5562_attributes,
 493};
 494
 495/* Chip specific configurations */
 496static struct lp55xx_device_config lp5562_cfg = {
 497        .max_channel  = LP5562_MAX_LEDS,
 498        .reset = {
 499                .addr = LP5562_REG_RESET,
 500                .val  = LP5562_RESET,
 501        },
 502        .enable = {
 503                .addr = LP5562_REG_ENABLE,
 504                .val  = LP5562_ENABLE_DEFAULT,
 505        },
 506        .post_init_device   = lp5562_post_init_device,
 507        .set_led_current    = lp5562_set_led_current,
 508        .brightness_fn      = lp5562_led_brightness,
 509        .run_engine         = lp5562_run_engine,
 510        .firmware_cb        = lp5562_firmware_loaded,
 511        .dev_attr_group     = &lp5562_group,
 512};
 513
 514static int lp5562_probe(struct i2c_client *client,
 515                        const struct i2c_device_id *id)
 516{
 517        int ret;
 518        struct lp55xx_chip *chip;
 519        struct lp55xx_led *led;
 520        struct lp55xx_platform_data *pdata = dev_get_platdata(&client->dev);
 521        struct device_node *np = client->dev.of_node;
 522
 523        if (!pdata) {
 524                if (np) {
 525                        pdata = lp55xx_of_populate_pdata(&client->dev, np);
 526                        if (IS_ERR(pdata))
 527                                return PTR_ERR(pdata);
 528                } else {
 529                        dev_err(&client->dev, "no platform data\n");
 530                        return -EINVAL;
 531                }
 532        }
 533
 534        chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
 535        if (!chip)
 536                return -ENOMEM;
 537
 538        led = devm_kcalloc(&client->dev,
 539                        pdata->num_channels, sizeof(*led), GFP_KERNEL);
 540        if (!led)
 541                return -ENOMEM;
 542
 543        chip->cl = client;
 544        chip->pdata = pdata;
 545        chip->cfg = &lp5562_cfg;
 546
 547        mutex_init(&chip->lock);
 548
 549        i2c_set_clientdata(client, led);
 550
 551        ret = lp55xx_init_device(chip);
 552        if (ret)
 553                goto err_init;
 554
 555        ret = lp55xx_register_leds(led, chip);
 556        if (ret)
 557                goto err_register_leds;
 558
 559        ret = lp55xx_register_sysfs(chip);
 560        if (ret) {
 561                dev_err(&client->dev, "registering sysfs failed\n");
 562                goto err_register_sysfs;
 563        }
 564
 565        return 0;
 566
 567err_register_sysfs:
 568        lp55xx_unregister_leds(led, chip);
 569err_register_leds:
 570        lp55xx_deinit_device(chip);
 571err_init:
 572        return ret;
 573}
 574
 575static int lp5562_remove(struct i2c_client *client)
 576{
 577        struct lp55xx_led *led = i2c_get_clientdata(client);
 578        struct lp55xx_chip *chip = led->chip;
 579
 580        lp5562_stop_engine(chip);
 581
 582        lp55xx_unregister_sysfs(chip);
 583        lp55xx_unregister_leds(led, chip);
 584        lp55xx_deinit_device(chip);
 585
 586        return 0;
 587}
 588
 589static const struct i2c_device_id lp5562_id[] = {
 590        { "lp5562", 0 },
 591        { }
 592};
 593MODULE_DEVICE_TABLE(i2c, lp5562_id);
 594
 595#ifdef CONFIG_OF
 596static const struct of_device_id of_lp5562_leds_match[] = {
 597        { .compatible = "ti,lp5562", },
 598        {},
 599};
 600
 601MODULE_DEVICE_TABLE(of, of_lp5562_leds_match);
 602#endif
 603
 604static struct i2c_driver lp5562_driver = {
 605        .driver = {
 606                .name   = "lp5562",
 607                .of_match_table = of_match_ptr(of_lp5562_leds_match),
 608        },
 609        .probe          = lp5562_probe,
 610        .remove         = lp5562_remove,
 611        .id_table       = lp5562_id,
 612};
 613
 614module_i2c_driver(lp5562_driver);
 615
 616MODULE_DESCRIPTION("Texas Instruments LP5562 LED Driver");
 617MODULE_AUTHOR("Milo Kim");
 618MODULE_LICENSE("GPL");
 619