root/drivers/iio/light/jsa1212.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * JSA1212 Ambient Light & Proximity Sensor Driver
 *
 * Copyright (c) 2014, Intel Corporation.
 *
 * JSA1212 I2C slave address: 0x44(ADDR tied to GND), 0x45(ADDR tied to VDD)
 *
 * TODO: Interrupt support, thresholds, range support.
 */

#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/mutex.h>
#include <linux/regmap.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>

/* JSA1212 reg address */
#define JSA1212_CONF_REG                0x01
#define JSA1212_INT_REG                 0x02
#define JSA1212_PXS_LT_REG              0x03
#define JSA1212_PXS_HT_REG              0x04
#define JSA1212_ALS_TH1_REG             0x05
#define JSA1212_ALS_TH2_REG             0x06
#define JSA1212_ALS_TH3_REG             0x07
#define JSA1212_PXS_DATA_REG            0x08
#define JSA1212_ALS_DT1_REG             0x09
#define JSA1212_ALS_DT2_REG             0x0A
#define JSA1212_ALS_RNG_REG             0x0B
#define JSA1212_MAX_REG                 0x0C

/* JSA1212 reg masks */
#define JSA1212_CONF_MASK               0xFF
#define JSA1212_INT_MASK                0xFF
#define JSA1212_PXS_LT_MASK             0xFF
#define JSA1212_PXS_HT_MASK             0xFF
#define JSA1212_ALS_TH1_MASK            0xFF
#define JSA1212_ALS_TH2_LT_MASK         0x0F
#define JSA1212_ALS_TH2_HT_MASK         0xF0
#define JSA1212_ALS_TH3_MASK            0xFF
#define JSA1212_PXS_DATA_MASK           0xFF
#define JSA1212_ALS_DATA_MASK           0x0FFF
#define JSA1212_ALS_DT1_MASK            0xFF
#define JSA1212_ALS_DT2_MASK            0x0F
#define JSA1212_ALS_RNG_MASK            0x07

/* JSA1212 CONF REG bits */
#define JSA1212_CONF_PXS_MASK           0x80
#define JSA1212_CONF_PXS_ENABLE         0x80
#define JSA1212_CONF_PXS_DISABLE        0x00
#define JSA1212_CONF_ALS_MASK           0x04
#define JSA1212_CONF_ALS_ENABLE         0x04
#define JSA1212_CONF_ALS_DISABLE        0x00
#define JSA1212_CONF_IRDR_MASK          0x08
/* Proxmity sensing IRDR current sink settings */
#define JSA1212_CONF_IRDR_200MA         0x08
#define JSA1212_CONF_IRDR_100MA         0x00
#define JSA1212_CONF_PXS_SLP_MASK       0x70
#define JSA1212_CONF_PXS_SLP_0MS        0x70
#define JSA1212_CONF_PXS_SLP_12MS       0x60
#define JSA1212_CONF_PXS_SLP_50MS       0x50
#define JSA1212_CONF_PXS_SLP_75MS       0x40
#define JSA1212_CONF_PXS_SLP_100MS      0x30
#define JSA1212_CONF_PXS_SLP_200MS      0x20
#define JSA1212_CONF_PXS_SLP_400MS      0x10
#define JSA1212_CONF_PXS_SLP_800MS      0x00

/* JSA1212 INT REG bits */
#define JSA1212_INT_CTRL_MASK           0x01
#define JSA1212_INT_CTRL_EITHER         0x00
#define JSA1212_INT_CTRL_BOTH           0x01
#define JSA1212_INT_ALS_PRST_MASK       0x06
#define JSA1212_INT_ALS_PRST_1CONV      0x00
#define JSA1212_INT_ALS_PRST_4CONV      0x02
#define JSA1212_INT_ALS_PRST_8CONV      0x04
#define JSA1212_INT_ALS_PRST_16CONV     0x06
#define JSA1212_INT_ALS_FLAG_MASK       0x08
#define JSA1212_INT_ALS_FLAG_CLR        0x00
#define JSA1212_INT_PXS_PRST_MASK       0x60
#define JSA1212_INT_PXS_PRST_1CONV      0x00
#define JSA1212_INT_PXS_PRST_4CONV      0x20
#define JSA1212_INT_PXS_PRST_8CONV      0x40
#define JSA1212_INT_PXS_PRST_16CONV     0x60
#define JSA1212_INT_PXS_FLAG_MASK       0x80
#define JSA1212_INT_PXS_FLAG_CLR        0x00

/* JSA1212 ALS RNG REG bits */
#define JSA1212_ALS_RNG_0_2048          0x00
#define JSA1212_ALS_RNG_0_1024          0x01
#define JSA1212_ALS_RNG_0_512           0x02
#define JSA1212_ALS_RNG_0_256           0x03
#define JSA1212_ALS_RNG_0_128           0x04

/* JSA1212 INT threshold range */
#define JSA1212_ALS_TH_MIN      0x0000
#define JSA1212_ALS_TH_MAX      0x0FFF
#define JSA1212_PXS_TH_MIN      0x00
#define JSA1212_PXS_TH_MAX      0xFF

#define JSA1212_ALS_DELAY_MS    200
#define JSA1212_PXS_DELAY_MS    100

#define JSA1212_DRIVER_NAME     "jsa1212"

enum jsa1212_op_mode {
        JSA1212_OPMODE_ALS_EN,
        JSA1212_OPMODE_PXS_EN,
};

struct jsa1212_data {
        struct i2c_client *client;
        struct mutex lock;
        u8 als_rng_idx;
        bool als_en; /* ALS enable status */
        bool pxs_en; /* proximity enable status */
        struct regmap *regmap;
};

/* ALS range idx to val mapping */
static const int jsa1212_als_range_val[] = {2048, 1024, 512, 256, 128,
                                                128, 128, 128};

/* Enables or disables ALS function based on status */
static int jsa1212_als_enable(struct jsa1212_data *data, u8 status)
{
        int ret;

        ret = regmap_update_bits(data->regmap, JSA1212_CONF_REG,
                                JSA1212_CONF_ALS_MASK,
                                status);
        if (ret < 0)
                return ret;

        data->als_en = !!status;

        return 0;
}

/* Enables or disables PXS function based on status */
static int jsa1212_pxs_enable(struct jsa1212_data *data, u8 status)
{
        int ret;

        ret = regmap_update_bits(data->regmap, JSA1212_CONF_REG,
                                JSA1212_CONF_PXS_MASK,
                                status);
        if (ret < 0)
                return ret;

        data->pxs_en = !!status;

        return 0;
}

static int jsa1212_read_als_data(struct jsa1212_data *data,
                                unsigned int *val)
{
        int ret;
        __le16 als_data;

        ret = jsa1212_als_enable(data, JSA1212_CONF_ALS_ENABLE);
        if (ret < 0)
                return ret;

        /* Delay for data output */
        msleep(JSA1212_ALS_DELAY_MS);

        /* Read 12 bit data */
        ret = regmap_bulk_read(data->regmap, JSA1212_ALS_DT1_REG, &als_data, 2);
        if (ret < 0) {
                dev_err(&data->client->dev, "als data read err\n");
                goto als_data_read_err;
        }

        *val = le16_to_cpu(als_data);

als_data_read_err:
        return jsa1212_als_enable(data, JSA1212_CONF_ALS_DISABLE);
}

static int jsa1212_read_pxs_data(struct jsa1212_data *data,
                                unsigned int *val)
{
        int ret;
        unsigned int pxs_data;

        ret = jsa1212_pxs_enable(data, JSA1212_CONF_PXS_ENABLE);
        if (ret < 0)
                return ret;

        /* Delay for data output */
        msleep(JSA1212_PXS_DELAY_MS);

        /* Read out all data */
        ret = regmap_read(data->regmap, JSA1212_PXS_DATA_REG, &pxs_data);
        if (ret < 0) {
                dev_err(&data->client->dev, "pxs data read err\n");
                goto pxs_data_read_err;
        }

        *val = pxs_data & JSA1212_PXS_DATA_MASK;

pxs_data_read_err:
        return jsa1212_pxs_enable(data, JSA1212_CONF_PXS_DISABLE);
}

static int jsa1212_read_raw(struct iio_dev *indio_dev,
                                struct iio_chan_spec const *chan,
                                int *val, int *val2, long mask)
{
        int ret;
        struct jsa1212_data *data = iio_priv(indio_dev);

        switch (mask) {
        case IIO_CHAN_INFO_RAW:
                mutex_lock(&data->lock);
                switch (chan->type) {
                case IIO_LIGHT:
                        ret = jsa1212_read_als_data(data, val);
                        break;
                case IIO_PROXIMITY:
                        ret = jsa1212_read_pxs_data(data, val);
                        break;
                default:
                        ret = -EINVAL;
                        break;
                }
                mutex_unlock(&data->lock);
                return ret < 0 ? ret : IIO_VAL_INT;
        case IIO_CHAN_INFO_SCALE:
                switch (chan->type) {
                case IIO_LIGHT:
                        *val = jsa1212_als_range_val[data->als_rng_idx];
                        *val2 = BIT(12); /* Max 12 bit value */
                        return IIO_VAL_FRACTIONAL;
                default:
                        break;
                }
                break;
        default:
                break;
        }

        return -EINVAL;
}

static const struct iio_chan_spec jsa1212_channels[] = {
        {
                .type = IIO_LIGHT,
                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
                        BIT(IIO_CHAN_INFO_SCALE),
        },
        {
                .type = IIO_PROXIMITY,
                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
        }
};

static const struct iio_info jsa1212_info = {
        .read_raw               = &jsa1212_read_raw,
};

static int jsa1212_chip_init(struct jsa1212_data *data)
{
        int ret;

        ret = regmap_write(data->regmap, JSA1212_CONF_REG,
                                (JSA1212_CONF_PXS_SLP_50MS |
                                JSA1212_CONF_IRDR_200MA));
        if (ret < 0)
                return ret;

        ret = regmap_write(data->regmap, JSA1212_INT_REG,
                                JSA1212_INT_ALS_PRST_4CONV);
        if (ret < 0)
                return ret;

        data->als_rng_idx = JSA1212_ALS_RNG_0_2048;

        return 0;
}

static bool jsa1212_is_volatile_reg(struct device *dev, unsigned int reg)
{
        switch (reg) {
        case JSA1212_PXS_DATA_REG:
        case JSA1212_ALS_DT1_REG:
        case JSA1212_ALS_DT2_REG:
        case JSA1212_INT_REG:
                return true;
        default:
                return false;
        }
}

static const struct regmap_config jsa1212_regmap_config = {
        .name = "jsa1212_regmap",
        .reg_bits = 8,
        .val_bits = 8,
        .max_register = JSA1212_MAX_REG,
        .cache_type = REGCACHE_RBTREE,
        .volatile_reg = jsa1212_is_volatile_reg,
};

static int jsa1212_probe(struct i2c_client *client)
{
        struct jsa1212_data *data;
        struct iio_dev *indio_dev;
        struct regmap *regmap;
        int ret;

        indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
        if (!indio_dev)
                return -ENOMEM;

        regmap = devm_regmap_init_i2c(client, &jsa1212_regmap_config);
        if (IS_ERR(regmap)) {
                dev_err(&client->dev, "Regmap initialization failed.\n");
                return PTR_ERR(regmap);
        }

        data = iio_priv(indio_dev);

        i2c_set_clientdata(client, indio_dev);
        data->client = client;
        data->regmap = regmap;

        mutex_init(&data->lock);

        ret = jsa1212_chip_init(data);
        if (ret < 0)
                return ret;

        indio_dev->channels = jsa1212_channels;
        indio_dev->num_channels = ARRAY_SIZE(jsa1212_channels);
        indio_dev->name = JSA1212_DRIVER_NAME;
        indio_dev->modes = INDIO_DIRECT_MODE;

        indio_dev->info = &jsa1212_info;

        ret = iio_device_register(indio_dev);
        if (ret < 0)
                dev_err(&client->dev, "%s: register device failed\n", __func__);

        return ret;
}

 /* power off the device */
static int jsa1212_power_off(struct jsa1212_data *data)
{
        int ret;

        mutex_lock(&data->lock);

        ret = regmap_update_bits(data->regmap, JSA1212_CONF_REG,
                                JSA1212_CONF_ALS_MASK |
                                JSA1212_CONF_PXS_MASK,
                                JSA1212_CONF_ALS_DISABLE |
                                JSA1212_CONF_PXS_DISABLE);

        if (ret < 0)
                dev_err(&data->client->dev, "power off cmd failed\n");

        mutex_unlock(&data->lock);

        return ret;
}

static void jsa1212_remove(struct i2c_client *client)
{
        struct iio_dev *indio_dev = i2c_get_clientdata(client);
        struct jsa1212_data *data = iio_priv(indio_dev);

        iio_device_unregister(indio_dev);

        jsa1212_power_off(data);
}

static int jsa1212_suspend(struct device *dev)
{
        struct jsa1212_data *data;

        data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));

        return jsa1212_power_off(data);
}

static int jsa1212_resume(struct device *dev)
{
        int ret = 0;
        struct jsa1212_data *data;

        data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));

        mutex_lock(&data->lock);

        if (data->als_en) {
                ret = jsa1212_als_enable(data, JSA1212_CONF_ALS_ENABLE);
                if (ret < 0) {
                        dev_err(dev, "als resume failed\n");
                        goto unlock_and_ret;
                }
        }

        if (data->pxs_en) {
                ret = jsa1212_pxs_enable(data, JSA1212_CONF_PXS_ENABLE);
                if (ret < 0)
                        dev_err(dev, "pxs resume failed\n");
        }

unlock_and_ret:
        mutex_unlock(&data->lock);
        return ret;
}

static DEFINE_SIMPLE_DEV_PM_OPS(jsa1212_pm_ops, jsa1212_suspend,
                                jsa1212_resume);

static const struct acpi_device_id jsa1212_acpi_match[] = {
        {"JSA1212", 0},
        { }
};
MODULE_DEVICE_TABLE(acpi, jsa1212_acpi_match);

static const struct i2c_device_id jsa1212_id[] = {
        { .name = JSA1212_DRIVER_NAME },
        { }
};
MODULE_DEVICE_TABLE(i2c, jsa1212_id);

static struct i2c_driver jsa1212_driver = {
        .driver = {
                .name   = JSA1212_DRIVER_NAME,
                .pm     = pm_sleep_ptr(&jsa1212_pm_ops),
                .acpi_match_table = jsa1212_acpi_match,
        },
        .probe          = jsa1212_probe,
        .remove         = jsa1212_remove,
        .id_table       = jsa1212_id,
};
module_i2c_driver(jsa1212_driver);

MODULE_AUTHOR("Sathya Kuppuswamy <sathyanarayanan.kuppuswamy@linux.intel.com>");
MODULE_DESCRIPTION("JSA1212 proximity/ambient light sensor driver");
MODULE_LICENSE("GPL v2");