leds-lm355x.c

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/*
* Simple driver for Texas Instruments LM355x LED Flash driver chip
* Copyright (C) 2012 Texas Instruments
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/

#include <linux/module.h>
#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/gpio.h>
#include <linux/leds.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/fs.h>
#include <linux/regmap.h>
#include <linux/workqueue.h>
#include <linux/platform_data/leds-lm355x.h>

enum lm355x_type {
    CHIP_LM3554 = 0,
    CHIP_LM3556,
};

enum lm355x_regs {
    REG_FLAG = 0,
    REG_TORCH_CFG,
    REG_TORCH_CTRL,
    REG_STROBE_CFG,
    REG_FLASH_CTRL,
    REG_INDI_CFG,
    REG_INDI_CTRL,
    REG_OPMODE,
    REG_MAX,
};

/* operation mode */
enum lm355x_mode {
    MODE_SHDN = 0,
    MODE_INDIC,
    MODE_TORCH,
    MODE_FLASH
};

/* register map info. */
struct lm355x_reg_data {
    u8 regno;
    u8 mask;
    u8 shift;
};

struct lm355x_chip_data {
    struct device *dev;
    enum lm355x_type type;

    struct led_classdev cdev_flash;
    struct led_classdev cdev_torch;
    struct led_classdev cdev_indicator;

    struct work_struct work_flash;
    struct work_struct work_torch;
    struct work_struct work_indicator;

    u8 br_flash;
    u8 br_torch;
    u8 br_indicator;

    struct lm355x_platform_data *pdata;
    struct regmap *regmap;
    struct mutex lock;

    unsigned int last_flag;
    struct lm355x_reg_data *regs;
};

/* specific indicator function for lm3556 */
enum lm3556_indic_pulse_time {
    PULSE_TIME_0_MS = 0,
    PULSE_TIME_32_MS,
    PULSE_TIME_64_MS,
    PULSE_TIME_92_MS,
    PULSE_TIME_128_MS,
    PULSE_TIME_160_MS,
    PULSE_TIME_196_MS,
    PULSE_TIME_224_MS,
    PULSE_TIME_256_MS,
    PULSE_TIME_288_MS,
    PULSE_TIME_320_MS,
    PULSE_TIME_352_MS,
    PULSE_TIME_384_MS,
    PULSE_TIME_416_MS,
    PULSE_TIME_448_MS,
    PULSE_TIME_480_MS,
};

enum lm3556_indic_n_blank {
    INDIC_N_BLANK_0 = 0,
    INDIC_N_BLANK_1,
    INDIC_N_BLANK_2,
    INDIC_N_BLANK_3,
    INDIC_N_BLANK_4,
    INDIC_N_BLANK_5,
    INDIC_N_BLANK_6,
    INDIC_N_BLANK_7,
    INDIC_N_BLANK_8,
    INDIC_N_BLANK_9,
    INDIC_N_BLANK_10,
    INDIC_N_BLANK_11,
    INDIC_N_BLANK_12,
    INDIC_N_BLANK_13,
    INDIC_N_BLANK_14,
    INDIC_N_BLANK_15,
};

enum lm3556_indic_period {
    INDIC_PERIOD_0 = 0,
    INDIC_PERIOD_1,
    INDIC_PERIOD_2,
    INDIC_PERIOD_3,
    INDIC_PERIOD_4,
    INDIC_PERIOD_5,
    INDIC_PERIOD_6,
    INDIC_PERIOD_7,
};

#define INDIC_PATTERN_SIZE 4

struct indicator {
    u8 blinking;
    u8 period_cnt;
};

/* indicator pattern data only for lm3556 */
static struct indicator indicator_pattern[INDIC_PATTERN_SIZE] = {
    [0] = {(INDIC_N_BLANK_1 << 4) | PULSE_TIME_32_MS, INDIC_PERIOD_1},
    [1] = {(INDIC_N_BLANK_15 << 4) | PULSE_TIME_32_MS, INDIC_PERIOD_2},
    [2] = {(INDIC_N_BLANK_10 << 4) | PULSE_TIME_32_MS, INDIC_PERIOD_4},
    [3] = {(INDIC_N_BLANK_5 << 4) | PULSE_TIME_32_MS, INDIC_PERIOD_7},
};

static struct lm355x_reg_data lm3554_regs[REG_MAX] = {
    [REG_FLAG] = {0xD0, 0xBF, 0},
    [REG_TORCH_CFG] = {0xE0, 0x80, 7},
    [REG_TORCH_CTRL] = {0xA0, 0x38, 3},
    [REG_STROBE_CFG] = {0xE0, 0x04, 2},
    [REG_FLASH_CTRL] = {0xB0, 0x78, 3},
    [REG_INDI_CFG] = {0xE0, 0x08, 3},
    [REG_INDI_CTRL] = {0xA0, 0xC0, 6},
    [REG_OPMODE] = {0xA0, 0x03, 0},
};

static struct lm355x_reg_data lm3556_regs[REG_MAX] = {
    [REG_FLAG] = {0x0B, 0xFF, 0},
    [REG_TORCH_CFG] = {0x0A, 0x10, 4},
    [REG_TORCH_CTRL] = {0x09, 0x70, 4},
    [REG_STROBE_CFG] = {0x0A, 0x20, 5},
    [REG_FLASH_CTRL] = {0x09, 0x0F, 0},
    [REG_INDI_CFG] = {0xFF, 0xFF, 0},
    [REG_INDI_CTRL] = {0x09, 0x70, 4},
    [REG_OPMODE] = {0x0A, 0x03, 0},
};

static char lm355x_name[][I2C_NAME_SIZE] = {
    [CHIP_LM3554] = LM3554_NAME,
    [CHIP_LM3556] = LM3556_NAME,
};

/* chip initialize */
static int __devinit lm355x_chip_init(struct lm355x_chip_data *chip)
{
    int ret;
    unsigned int reg_val;
    struct lm355x_platform_data *pdata = chip->pdata;

    /* input and output pins configuration */
    switch (chip->type) {
    case CHIP_LM3554:
        reg_val = pdata->pin_tx2 | pdata->ntc_pin;
        ret = regmap_update_bits(chip->regmap, 0xE0, 0x28, reg_val);
        if (ret < 0)
            goto out;
        reg_val = pdata->pass_mode;
        ret = regmap_update_bits(chip->regmap, 0xA0, 0x04, reg_val);
        if (ret < 0)
            goto out;
        break;

    case CHIP_LM3556:
        reg_val = pdata->pin_tx2 | pdata->ntc_pin | pdata->pass_mode;
        ret = regmap_update_bits(chip->regmap, 0x0A, 0xC4, reg_val);
        if (ret < 0)
            goto out;
        break;
    default:
        return -ENODATA;
    }

    return ret;
out:
    dev_err(chip->dev, "%s:i2c access fail to register\n", __func__);
    return ret;
}

/* chip control */
static void lm355x_control(struct lm355x_chip_data *chip,
               u8 brightness, enum lm355x_mode opmode)
{
    int ret;
    unsigned int reg_val;
    struct lm355x_platform_data *pdata = chip->pdata;
    struct lm355x_reg_data *preg = chip->regs;

    ret = regmap_read(chip->regmap, preg[REG_FLAG].regno, &chip->last_flag);
    if (ret < 0)
        goto out;
    if (chip->last_flag & preg[REG_FLAG].mask)
        dev_info(chip->dev, "%s Last FLAG is 0x%x\n",
             lm355x_name[chip->type],
             chip->last_flag & preg[REG_FLAG].mask);
    /* brightness 0 means shutdown */
    if (!brightness)
        opmode = MODE_SHDN;

    switch (opmode) {
    case MODE_TORCH:
        ret =
            regmap_update_bits(chip->regmap, preg[REG_TORCH_CTRL].regno,
                       preg[REG_TORCH_CTRL].mask,
                       (brightness - 1)
                       << preg[REG_TORCH_CTRL].shift);
        if (ret < 0)
            goto out;

        if (pdata->pin_tx1 != LM355x_PIN_TORCH_DISABLE) {
            ret =
                regmap_update_bits(chip->regmap,
                           preg[REG_TORCH_CFG].regno,
                           preg[REG_TORCH_CFG].mask,
                           0x01 <<
                           preg[REG_TORCH_CFG].shift);
            if (ret < 0)
                goto out;
            opmode = MODE_SHDN;
            dev_info(chip->dev,
                 "torch brt is set - ext. torch pin mode\n");
        }
        break;

    case MODE_FLASH:

        ret =
            regmap_update_bits(chip->regmap, preg[REG_FLASH_CTRL].regno,
                       preg[REG_FLASH_CTRL].mask,
                       (brightness - 1)
                       << preg[REG_FLASH_CTRL].shift);
        if (ret < 0)
            goto out;

        if (pdata->pin_strobe != LM355x_PIN_STROBE_DISABLE) {
            if (chip->type == CHIP_LM3554)
                reg_val = 0x00;
            else
                reg_val = 0x01;
            ret =
                regmap_update_bits(chip->regmap,
                           preg[REG_STROBE_CFG].regno,
                           preg[REG_STROBE_CFG].mask,
                           reg_val <<
                           preg[REG_STROBE_CFG].shift);
            if (ret < 0)
                goto out;
            opmode = MODE_SHDN;
            dev_info(chip->dev,
                 "flash brt is set - ext. strobe pin mode\n");
        }
        break;

    case MODE_INDIC:
        ret =
            regmap_update_bits(chip->regmap, preg[REG_INDI_CTRL].regno,
                       preg[REG_INDI_CTRL].mask,
                       (brightness - 1)
                       << preg[REG_INDI_CTRL].shift);
        if (ret < 0)
            goto out;

        if (pdata->pin_tx2 != LM355x_PIN_TX_DISABLE) {
            ret =
                regmap_update_bits(chip->regmap,
                           preg[REG_INDI_CFG].regno,
                           preg[REG_INDI_CFG].mask,
                           0x01 <<
                           preg[REG_INDI_CFG].shift);
            if (ret < 0)
                goto out;
            opmode = MODE_SHDN;
        }
        break;
    case MODE_SHDN:
        break;
    default:
        return;
    }
    /* operation mode control */
    ret = regmap_update_bits(chip->regmap, preg[REG_OPMODE].regno,
                 preg[REG_OPMODE].mask,
                 opmode << preg[REG_OPMODE].shift);
    if (ret < 0)
        goto out;
    return;
out:
    dev_err(chip->dev, "%s:i2c access fail to register\n", __func__);
    return;
}

/* torch */
static void lm355x_deferred_torch_brightness_set(struct work_struct *work)
{
    struct lm355x_chip_data *chip =
        container_of(work, struct lm355x_chip_data, work_torch);

    mutex_lock(&chip->lock);
    lm355x_control(chip, chip->br_torch, MODE_TORCH);
    mutex_unlock(&chip->lock);
}

static void lm355x_torch_brightness_set(struct led_classdev *cdev,
                    enum led_brightness brightness)
{
    struct lm355x_chip_data *chip =
        container_of(cdev, struct lm355x_chip_data, cdev_torch);

    chip->br_torch = brightness;
    schedule_work(&chip->work_torch);
}

/* flash */
static void lm355x_deferred_strobe_brightness_set(struct work_struct *work)
{
    struct lm355x_chip_data *chip =
        container_of(work, struct lm355x_chip_data, work_flash);

    mutex_lock(&chip->lock);
    lm355x_control(chip, chip->br_flash, MODE_FLASH);
    mutex_unlock(&chip->lock);
}

static void lm355x_strobe_brightness_set(struct led_classdev *cdev,
                     enum led_brightness brightness)
{
    struct lm355x_chip_data *chip =
        container_of(cdev, struct lm355x_chip_data, cdev_flash);

    chip->br_flash = brightness;
    schedule_work(&chip->work_flash);
}

/* indicator */
static void lm355x_deferred_indicator_brightness_set(struct work_struct *work)
{
    struct lm355x_chip_data *chip =
        container_of(work, struct lm355x_chip_data, work_indicator);

    mutex_lock(&chip->lock);
    lm355x_control(chip, chip->br_indicator, MODE_INDIC);
    mutex_unlock(&chip->lock);
}

static void lm355x_indicator_brightness_set(struct led_classdev *cdev,
                        enum led_brightness brightness)
{
    struct lm355x_chip_data *chip =
        container_of(cdev, struct lm355x_chip_data, cdev_indicator);

    chip->br_indicator = brightness;
    schedule_work(&chip->work_indicator);
}

/* indicator pattern only for lm3556*/
static ssize_t lm3556_indicator_pattern_store(struct device *dev,
                          struct device_attribute *devAttr,
                          const char *buf, size_t size)
{
    ssize_t ret;
    struct led_classdev *led_cdev = dev_get_drvdata(dev);
    struct lm355x_chip_data *chip =
        container_of(led_cdev, struct lm355x_chip_data, cdev_indicator);
    unsigned int state;

    ret = kstrtouint(buf, 10, &state);
    if (ret)
        goto out;
    if (state > INDIC_PATTERN_SIZE - 1)
        state = INDIC_PATTERN_SIZE - 1;

    ret = regmap_write(chip->regmap, 0x04,
               indicator_pattern[state].blinking);
    if (ret < 0)
        goto out;

    ret = regmap_write(chip->regmap, 0x05,
               indicator_pattern[state].period_cnt);
    if (ret < 0)
        goto out;

    return size;
out:
    dev_err(chip->dev, "%s:i2c access fail to register\n", __func__);
    return size;
}

static DEVICE_ATTR(pattern, 0666, NULL, lm3556_indicator_pattern_store);

static const struct regmap_config lm355x_regmap = {
    .reg_bits = 8,
    .val_bits = 8,
    .max_register = 0xFF,
};

/* module initialize */
static int __devinit lm355x_probe(struct i2c_client *client,
                  const struct i2c_device_id *id)
{
    struct lm355x_platform_data *pdata = client->dev.platform_data;
    struct lm355x_chip_data *chip;

    int err;

    if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
        dev_err(&client->dev, "i2c functionality check fail.\n");
        return -EOPNOTSUPP;
    }

    if (pdata == NULL) {
        dev_err(&client->dev, "needs Platform Data.\n");
        return -ENODATA;
    }

    chip = devm_kzalloc(&client->dev,
                sizeof(struct lm355x_chip_data), GFP_KERNEL);
    if (!chip)
        return -ENOMEM;

    chip->dev = &client->dev;
    chip->type = id->driver_data;
    switch (id->driver_data) {
    case CHIP_LM3554:
        chip->regs = lm3554_regs;
        break;
    case CHIP_LM3556:
        chip->regs = lm3556_regs;
        break;
    default:
        return -ENOSYS;
    }
    chip->pdata = pdata;

    chip->regmap = devm_regmap_init_i2c(client, &lm355x_regmap);
    if (IS_ERR(chip->regmap)) {
        err = PTR_ERR(chip->regmap);
        dev_err(&client->dev,
            "Failed to allocate register map: %d\n", err);
        return err;
    }

    mutex_init(&chip->lock);
    i2c_set_clientdata(client, chip);

    err = lm355x_chip_init(chip);
    if (err < 0)
        goto err_out;

    /* flash */
    INIT_WORK(&chip->work_flash, lm355x_deferred_strobe_brightness_set);
    chip->cdev_flash.name = "flash";
    chip->cdev_flash.max_brightness = 16;
    chip->cdev_flash.brightness_set = lm355x_strobe_brightness_set;
    err = led_classdev_register((struct device *)
                    &client->dev, &chip->cdev_flash);
    if (err < 0)
        goto err_out;
    /* torch */
    INIT_WORK(&chip->work_torch, lm355x_deferred_torch_brightness_set);
    chip->cdev_torch.name = "torch";
    chip->cdev_torch.max_brightness = 8;
    chip->cdev_torch.brightness_set = lm355x_torch_brightness_set;
    err = led_classdev_register((struct device *)
                    &client->dev, &chip->cdev_torch);
    if (err < 0)
        goto err_create_torch_file;
    /* indicator */
    INIT_WORK(&chip->work_indicator,
          lm355x_deferred_indicator_brightness_set);
    chip->cdev_indicator.name = "indicator";
    if (id->driver_data == CHIP_LM3554)
        chip->cdev_indicator.max_brightness = 4;
    else
        chip->cdev_indicator.max_brightness = 8;
    chip->cdev_indicator.brightness_set = lm355x_indicator_brightness_set;
    err = led_classdev_register((struct device *)
                    &client->dev, &chip->cdev_indicator);
    if (err < 0)
        goto err_create_indicator_file;
    /* indicator pattern control only for LM3554 */
    if (id->driver_data == CHIP_LM3556) {
        err =
            device_create_file(chip->cdev_indicator.dev,
                       &dev_attr_pattern);
        if (err < 0)
            goto err_create_pattern_file;
    }

    dev_info(&client->dev, "%s is initialized\n",
         lm355x_name[id->driver_data]);
    return 0;

err_create_pattern_file:
    led_classdev_unregister(&chip->cdev_indicator);
err_create_indicator_file:
    led_classdev_unregister(&chip->cdev_torch);
err_create_torch_file:
    led_classdev_unregister(&chip->cdev_flash);
err_out:
    return err;
}

static int __devexit lm355x_remove(struct i2c_client *client)
{
    struct lm355x_chip_data *chip = i2c_get_clientdata(client);
    struct lm355x_reg_data *preg = chip->regs;

    regmap_write(chip->regmap, preg[REG_OPMODE].regno, 0);
    if (chip->type == CHIP_LM3556)
        device_remove_file(chip->cdev_indicator.dev, &dev_attr_pattern);
    led_classdev_unregister(&chip->cdev_indicator);
    flush_work(&chip->work_indicator);
    led_classdev_unregister(&chip->cdev_torch);
    flush_work(&chip->work_torch);
    led_classdev_unregister(&chip->cdev_flash);
    flush_work(&chip->work_flash);
    dev_info(&client->dev, "%s is removed\n", lm355x_name[chip->type]);

    return 0;
}

static const struct i2c_device_id lm355x_id[] = {
    {LM3554_NAME, CHIP_LM3554},
    {LM3556_NAME, CHIP_LM3556},
    {}
};

MODULE_DEVICE_TABLE(i2c, lm355x_id);

static struct i2c_driver lm355x_i2c_driver = {
    .driver = {
           .name = LM355x_NAME,
           .owner = THIS_MODULE,
           .pm = NULL,
           },
    .probe = lm355x_probe,
    .remove = __devexit_p(lm355x_remove),
    .id_table = lm355x_id,
};

module_i2c_driver(lm355x_i2c_driver);

MODULE_DESCRIPTION("Texas Instruments Flash Lighting driver for LM355x");
MODULE_AUTHOR("Daniel Jeong <[email protected]>");
MODULE_AUTHOR("G.Shark Jeong <[email protected]>");
MODULE_LICENSE("GPL v2");