// SPDX-License-Identifier: GPL-2.0+
/*
 * ADIS16460 IMU driver
 *
 * Copyright 2019 Analog Devices Inc.
 */

#include <linux/module.h>
#include <linux/spi/spi.h>

#include <linux/iio/iio.h>
#include <linux/iio/imu/adis.h>

#include <linux/debugfs.h>

#define ADIS16460_REG_FLASH_CNT         0x00
#define ADIS16460_REG_DIAG_STAT         0x02
#define ADIS16460_REG_X_GYRO_LOW        0x04
#define ADIS16460_REG_X_GYRO_OUT        0x06
#define ADIS16460_REG_Y_GYRO_LOW        0x08
#define ADIS16460_REG_Y_GYRO_OUT        0x0A
#define ADIS16460_REG_Z_GYRO_LOW        0x0C
#define ADIS16460_REG_Z_GYRO_OUT        0x0E
#define ADIS16460_REG_X_ACCL_LOW        0x10
#define ADIS16460_REG_X_ACCL_OUT        0x12
#define ADIS16460_REG_Y_ACCL_LOW        0x14
#define ADIS16460_REG_Y_ACCL_OUT        0x16
#define ADIS16460_REG_Z_ACCL_LOW        0x18
#define ADIS16460_REG_Z_ACCL_OUT        0x1A
#define ADIS16460_REG_SMPL_CNTR         0x1C
#define ADIS16460_REG_TEMP_OUT          0x1E
#define ADIS16460_REG_X_DELT_ANG        0x24
#define ADIS16460_REG_Y_DELT_ANG        0x26
#define ADIS16460_REG_Z_DELT_ANG        0x28
#define ADIS16460_REG_X_DELT_VEL        0x2A
#define ADIS16460_REG_Y_DELT_VEL        0x2C
#define ADIS16460_REG_Z_DELT_VEL        0x2E
#define ADIS16460_REG_MSC_CTRL          0x32
#define ADIS16460_REG_SYNC_SCAL         0x34
#define ADIS16460_REG_DEC_RATE          0x36
#define ADIS16460_REG_FLTR_CTRL         0x38
#define ADIS16460_REG_GLOB_CMD          0x3E
#define ADIS16460_REG_X_GYRO_OFF        0x40
#define ADIS16460_REG_Y_GYRO_OFF        0x42
#define ADIS16460_REG_Z_GYRO_OFF        0x44
#define ADIS16460_REG_X_ACCL_OFF        0x46
#define ADIS16460_REG_Y_ACCL_OFF        0x48
#define ADIS16460_REG_Z_ACCL_OFF        0x4A
#define ADIS16460_REG_LOT_ID1           0x52
#define ADIS16460_REG_LOT_ID2           0x54
#define ADIS16460_REG_PROD_ID           0x56
#define ADIS16460_REG_SERIAL_NUM        0x58
#define ADIS16460_REG_CAL_SGNTR         0x60
#define ADIS16460_REG_CAL_CRC           0x62
#define ADIS16460_REG_CODE_SGNTR        0x64
#define ADIS16460_REG_CODE_CRC          0x66

struct adis16460_chip_info {
        unsigned int num_channels;
        const struct iio_chan_spec *channels;
        unsigned int gyro_max_val;
        unsigned int gyro_max_scale;
        unsigned int accel_max_val;
        unsigned int accel_max_scale;
};

struct adis16460 {
        const struct adis16460_chip_info *chip_info;
        struct adis adis;
};

static int adis16460_show_serial_number(void *arg, u64 *val)
{
        struct adis16460 *adis16460 = arg;
        u16 serial;
        int ret;

        ret = adis_read_reg_16(&adis16460->adis, ADIS16460_REG_SERIAL_NUM,
                &serial);
        if (ret)
                return ret;

        *val = serial;

        return 0;
}
DEFINE_DEBUGFS_ATTRIBUTE(adis16460_serial_number_fops,
                adis16460_show_serial_number, NULL, "0x%.4llx\n");

static int adis16460_show_product_id(void *arg, u64 *val)
{
        struct adis16460 *adis16460 = arg;
        u16 prod_id;
        int ret;

        ret = adis_read_reg_16(&adis16460->adis, ADIS16460_REG_PROD_ID,
                &prod_id);
        if (ret)
                return ret;

        *val = prod_id;

        return 0;
}
DEFINE_DEBUGFS_ATTRIBUTE(adis16460_product_id_fops,
                adis16460_show_product_id, NULL, "%llu\n");

static int adis16460_show_flash_count(void *arg, u64 *val)
{
        struct adis16460 *adis16460 = arg;
        u32 flash_count;
        int ret;

        ret = adis_read_reg_32(&adis16460->adis, ADIS16460_REG_FLASH_CNT,
                &flash_count);
        if (ret)
                return ret;

        *val = flash_count;

        return 0;
}
DEFINE_DEBUGFS_ATTRIBUTE(adis16460_flash_count_fops,
                adis16460_show_flash_count, NULL, "%lld\n");

static void adis16460_debugfs_init(struct iio_dev *indio_dev)
{
        struct adis16460 *adis16460 = iio_priv(indio_dev);
        struct dentry *d = iio_get_debugfs_dentry(indio_dev);

        if (!IS_ENABLED(CONFIG_DEBUG_FS))
                return;

        debugfs_create_file_unsafe("serial_number", 0400,
                        d, adis16460, &adis16460_serial_number_fops);
        debugfs_create_file_unsafe("product_id", 0400,
                        d, adis16460, &adis16460_product_id_fops);
        debugfs_create_file_unsafe("flash_count", 0400,
                        d, adis16460, &adis16460_flash_count_fops);
}

static int adis16460_set_freq(struct iio_dev *indio_dev, int val, int val2)
{
        struct adis16460 *st = iio_priv(indio_dev);
        int t;

        t =  val * 1000 + val2 / 1000;
        if (t <= 0)
                return -EINVAL;

        t = 2048000 / t;
        if (t > 2048)
                t = 2048;

        if (t != 0)
                t--;

        return adis_write_reg_16(&st->adis, ADIS16460_REG_DEC_RATE, t);
}

static int adis16460_get_freq(struct iio_dev *indio_dev, int *val, int *val2)
{
        struct adis16460 *st = iio_priv(indio_dev);
        uint16_t t;
        int ret;
        unsigned int freq;

        ret = adis_read_reg_16(&st->adis, ADIS16460_REG_DEC_RATE, &t);
        if (ret)
                return ret;

        freq = 2048000 / (t + 1);
        *val = freq / 1000;
        *val2 = (freq % 1000) * 1000;

        return IIO_VAL_INT_PLUS_MICRO;
}

static int adis16460_read_raw(struct iio_dev *indio_dev,
        const struct iio_chan_spec *chan, int *val, int *val2, long info)
{
        struct adis16460 *st = iio_priv(indio_dev);

        switch (info) {
        case IIO_CHAN_INFO_RAW:
                return adis_single_conversion(indio_dev, chan, 0, val);
        case IIO_CHAN_INFO_SCALE:
                switch (chan->type) {
                case IIO_ANGL_VEL:
                        *val = st->chip_info->gyro_max_scale;
                        *val2 = st->chip_info->gyro_max_val;
                        return IIO_VAL_FRACTIONAL;
                case IIO_ACCEL:
                        *val = st->chip_info->accel_max_scale;
                        *val2 = st->chip_info->accel_max_val;
                        return IIO_VAL_FRACTIONAL;
                case IIO_TEMP:
                        *val = 50; /* 50 milli degrees Celsius/LSB */
                        return IIO_VAL_INT;
                default:
                        return -EINVAL;
                }
        case IIO_CHAN_INFO_OFFSET:
                *val = 500; /* 25 degrees Celsius = 0x0000 */
                return IIO_VAL_INT;
        case IIO_CHAN_INFO_SAMP_FREQ:
                return adis16460_get_freq(indio_dev, val, val2);
        default:
                return -EINVAL;
        }
}

static int adis16460_write_raw(struct iio_dev *indio_dev,
        const struct iio_chan_spec *chan, int val, int val2, long info)
{
        switch (info) {
        case IIO_CHAN_INFO_SAMP_FREQ:
                return adis16460_set_freq(indio_dev, val, val2);
        default:
                return -EINVAL;
        }
}

enum {
        ADIS16460_SCAN_GYRO_X,
        ADIS16460_SCAN_GYRO_Y,
        ADIS16460_SCAN_GYRO_Z,
        ADIS16460_SCAN_ACCEL_X,
        ADIS16460_SCAN_ACCEL_Y,
        ADIS16460_SCAN_ACCEL_Z,
        ADIS16460_SCAN_TEMP,
};

#define ADIS16460_MOD_CHANNEL(_type, _mod, _address, _si, _bits) \
        { \
                .type = (_type), \
                .modified = 1, \
                .channel2 = (_mod), \
                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
                .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
                .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
                .address = (_address), \
                .scan_index = (_si), \
                .scan_type = { \
                        .sign = 's', \
                        .realbits = (_bits), \
                        .storagebits = (_bits), \
                        .endianness = IIO_BE, \
                }, \
        }

#define ADIS16460_GYRO_CHANNEL(_mod) \
        ADIS16460_MOD_CHANNEL(IIO_ANGL_VEL, IIO_MOD_ ## _mod, \
        ADIS16460_REG_ ## _mod ## _GYRO_LOW, ADIS16460_SCAN_GYRO_ ## _mod, \
        32)

#define ADIS16460_ACCEL_CHANNEL(_mod) \
        ADIS16460_MOD_CHANNEL(IIO_ACCEL, IIO_MOD_ ## _mod, \
        ADIS16460_REG_ ## _mod ## _ACCL_LOW, ADIS16460_SCAN_ACCEL_ ## _mod, \
        32)

#define ADIS16460_TEMP_CHANNEL() { \
                .type = IIO_TEMP, \
                .indexed = 1, \
                .channel = 0, \
                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
                        BIT(IIO_CHAN_INFO_SCALE) | \
                        BIT(IIO_CHAN_INFO_OFFSET), \
                .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
                .address = ADIS16460_REG_TEMP_OUT, \
                .scan_index = ADIS16460_SCAN_TEMP, \
                .scan_type = { \
                        .sign = 's', \
                        .realbits = 16, \
                        .storagebits = 16, \
                        .endianness = IIO_BE, \
                }, \
        }

static const struct iio_chan_spec adis16460_channels[] = {
        ADIS16460_GYRO_CHANNEL(X),
        ADIS16460_GYRO_CHANNEL(Y),
        ADIS16460_GYRO_CHANNEL(Z),
        ADIS16460_ACCEL_CHANNEL(X),
        ADIS16460_ACCEL_CHANNEL(Y),
        ADIS16460_ACCEL_CHANNEL(Z),
        ADIS16460_TEMP_CHANNEL(),
        IIO_CHAN_SOFT_TIMESTAMP(7)
};

static const struct adis16460_chip_info adis16460_chip_info = {
        .channels = adis16460_channels,
        .num_channels = ARRAY_SIZE(adis16460_channels),
        /*
         * storing the value in rad/degree and the scale in degree
         * gives us the result in rad and better precession than
         * storing the scale directly in rad.
         */
        .gyro_max_val = IIO_RAD_TO_DEGREE(200 << 16),
        .gyro_max_scale = 1,
        .accel_max_val = IIO_M_S_2_TO_G(20000 << 16),
        .accel_max_scale = 5,
};

static const struct iio_info adis16460_info = {
        .read_raw = &adis16460_read_raw,
        .write_raw = &adis16460_write_raw,
        .update_scan_mode = adis_update_scan_mode,
        .debugfs_reg_access = adis_debugfs_reg_access,
};

#define ADIS16460_DIAG_STAT_IN_CLK_OOS  7
#define ADIS16460_DIAG_STAT_FLASH_MEM   6
#define ADIS16460_DIAG_STAT_SELF_TEST   5
#define ADIS16460_DIAG_STAT_OVERRANGE   4
#define ADIS16460_DIAG_STAT_SPI_COMM    3
#define ADIS16460_DIAG_STAT_FLASH_UPT   2

static const char * const adis16460_status_error_msgs[] = {
        [ADIS16460_DIAG_STAT_IN_CLK_OOS] = "Input clock out of sync",
        [ADIS16460_DIAG_STAT_FLASH_MEM] = "Flash memory failure",
        [ADIS16460_DIAG_STAT_SELF_TEST] = "Self test diagnostic failure",
        [ADIS16460_DIAG_STAT_OVERRANGE] = "Sensor overrange",
        [ADIS16460_DIAG_STAT_SPI_COMM] = "SPI communication failure",
        [ADIS16460_DIAG_STAT_FLASH_UPT] = "Flash update failure",
};

static const struct adis_timeout adis16460_timeouts = {
        .reset_ms = 225,
        .sw_reset_ms = 225,
        .self_test_ms = 10,
};

static const struct adis_data adis16460_data = {
        .diag_stat_reg = ADIS16460_REG_DIAG_STAT,
        .glob_cmd_reg = ADIS16460_REG_GLOB_CMD,
        .prod_id_reg = ADIS16460_REG_PROD_ID,
        .prod_id = 16460,
        .self_test_mask = BIT(2),
        .self_test_reg = ADIS16460_REG_GLOB_CMD,
        .has_paging = false,
        .read_delay = 5,
        .write_delay = 5,
        .cs_change_delay = 16,
        .status_error_msgs = adis16460_status_error_msgs,
        .status_error_mask = BIT(ADIS16460_DIAG_STAT_IN_CLK_OOS) |
                BIT(ADIS16460_DIAG_STAT_FLASH_MEM) |
                BIT(ADIS16460_DIAG_STAT_SELF_TEST) |
                BIT(ADIS16460_DIAG_STAT_OVERRANGE) |
                BIT(ADIS16460_DIAG_STAT_SPI_COMM) |
                BIT(ADIS16460_DIAG_STAT_FLASH_UPT),
        .unmasked_drdy = true,
        .timeouts = &adis16460_timeouts,
};

static int adis16460_probe(struct spi_device *spi)
{
        struct iio_dev *indio_dev;
        struct adis16460 *st;
        int ret;

        indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st));
        if (indio_dev == NULL)
                return -ENOMEM;

        st = iio_priv(indio_dev);

        st->chip_info = &adis16460_chip_info;
        indio_dev->name = spi_get_device_id(spi)->name;
        indio_dev->channels = st->chip_info->channels;
        indio_dev->num_channels = st->chip_info->num_channels;
        indio_dev->info = &adis16460_info;
        indio_dev->modes = INDIO_DIRECT_MODE;

        ret = adis_init(&st->adis, indio_dev, spi, &adis16460_data);
        if (ret)
                return ret;

        ret = devm_adis_setup_buffer_and_trigger(&st->adis, indio_dev, NULL);
        if (ret)
                return ret;

        ret = __adis_initial_startup(&st->adis);
        if (ret)
                return ret;

        ret = devm_iio_device_register(&spi->dev, indio_dev);
        if (ret)
                return ret;

        adis16460_debugfs_init(indio_dev);

        return 0;
}

static const struct spi_device_id adis16460_ids[] = {
        { "adis16460", 0 },
        { }
};
MODULE_DEVICE_TABLE(spi, adis16460_ids);

static const struct of_device_id adis16460_of_match[] = {
        { .compatible = "adi,adis16460" },
        { }
};
MODULE_DEVICE_TABLE(of, adis16460_of_match);

static struct spi_driver adis16460_driver = {
        .driver = {
                .name = "adis16460",
                .of_match_table = adis16460_of_match,
        },
        .id_table = adis16460_ids,
        .probe = adis16460_probe,
};
module_spi_driver(adis16460_driver);

MODULE_AUTHOR("Dragos Bogdan <dragos.bogdan@analog.com>");
MODULE_DESCRIPTION("Analog Devices ADIS16460 IMU driver");
MODULE_LICENSE("GPL");
MODULE_IMPORT_NS("IIO_ADISLIB");