// SPDX-License-Identifier: GPL-2.0-only
/*
 * ADIS16133/ADIS16135/ADIS16136 gyroscope driver
 *
 * Copyright 2012 Analog Devices Inc.
 *   Author: Lars-Peter Clausen <lars@metafoo.de>
 */

#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/spi/spi.h>
#include <linux/sysfs.h>
#include <linux/module.h>

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

#include <linux/debugfs.h>

#define ADIS16136_REG_FLASH_CNT         0x00
#define ADIS16136_REG_TEMP_OUT          0x02
#define ADIS16136_REG_GYRO_OUT2         0x04
#define ADIS16136_REG_GYRO_OUT          0x06
#define ADIS16136_REG_GYRO_OFF2         0x08
#define ADIS16136_REG_GYRO_OFF          0x0A
#define ADIS16136_REG_ALM_MAG1          0x10
#define ADIS16136_REG_ALM_MAG2          0x12
#define ADIS16136_REG_ALM_SAMPL1        0x14
#define ADIS16136_REG_ALM_SAMPL2        0x16
#define ADIS16136_REG_ALM_CTRL          0x18
#define ADIS16136_REG_GPIO_CTRL         0x1A
#define ADIS16136_REG_MSC_CTRL          0x1C
#define ADIS16136_REG_SMPL_PRD          0x1E
#define ADIS16136_REG_AVG_CNT           0x20
#define ADIS16136_REG_DEC_RATE          0x22
#define ADIS16136_REG_SLP_CTRL          0x24
#define ADIS16136_REG_DIAG_STAT         0x26
#define ADIS16136_REG_GLOB_CMD          0x28
#define ADIS16136_REG_LOT1              0x32
#define ADIS16136_REG_LOT2              0x34
#define ADIS16136_REG_LOT3              0x36
#define ADIS16136_REG_PROD_ID           0x38
#define ADIS16136_REG_SERIAL_NUM        0x3A

#define ADIS16136_DIAG_STAT_FLASH_UPDATE_FAIL   2
#define ADIS16136_DIAG_STAT_SPI_FAIL            3
#define ADIS16136_DIAG_STAT_SELF_TEST_FAIL      5
#define ADIS16136_DIAG_STAT_FLASH_CHKSUM_FAIL   6

#define ADIS16136_MSC_CTRL_MEMORY_TEST BIT(11)
#define ADIS16136_MSC_CTRL_SELF_TEST BIT(10)

struct adis16136_chip_info {
        unsigned int precision;
        unsigned int fullscale;
        const struct adis_data adis_data;
};

struct adis16136 {
        const struct adis16136_chip_info *chip_info;

        struct adis adis;
};

#ifdef CONFIG_DEBUG_FS

static ssize_t adis16136_show_serial(struct file *file,
                char __user *userbuf, size_t count, loff_t *ppos)
{
        struct adis16136 *adis16136 = file->private_data;
        uint16_t lot1, lot2, lot3, serial;
        char buf[20];
        size_t len;
        int ret;

        ret = adis_read_reg_16(&adis16136->adis, ADIS16136_REG_SERIAL_NUM,
                &serial);
        if (ret)
                return ret;

        ret = adis_read_reg_16(&adis16136->adis, ADIS16136_REG_LOT1, &lot1);
        if (ret)
                return ret;

        ret = adis_read_reg_16(&adis16136->adis, ADIS16136_REG_LOT2, &lot2);
        if (ret)
                return ret;

        ret = adis_read_reg_16(&adis16136->adis, ADIS16136_REG_LOT3, &lot3);
        if (ret)
                return ret;

        len = snprintf(buf, sizeof(buf), "%.4x%.4x%.4x-%.4x\n", lot1, lot2,
                lot3, serial);

        return simple_read_from_buffer(userbuf, count, ppos, buf, len);
}

static const struct file_operations adis16136_serial_fops = {
        .open = simple_open,
        .read = adis16136_show_serial,
        .llseek = default_llseek,
        .owner = THIS_MODULE,
};

static int adis16136_show_product_id(void *arg, u64 *val)
{
        struct adis16136 *adis16136 = arg;
        u16 prod_id;
        int ret;

        ret = adis_read_reg_16(&adis16136->adis, ADIS16136_REG_PROD_ID,
                &prod_id);
        if (ret)
                return ret;

        *val = prod_id;

        return 0;
}
DEFINE_DEBUGFS_ATTRIBUTE(adis16136_product_id_fops,
        adis16136_show_product_id, NULL, "%llu\n");

static int adis16136_show_flash_count(void *arg, u64 *val)
{
        struct adis16136 *adis16136 = arg;
        uint16_t flash_count;
        int ret;

        ret = adis_read_reg_16(&adis16136->adis, ADIS16136_REG_FLASH_CNT,
                &flash_count);
        if (ret)
                return ret;

        *val = flash_count;

        return 0;
}
DEFINE_DEBUGFS_ATTRIBUTE(adis16136_flash_count_fops,
        adis16136_show_flash_count, NULL, "%lld\n");

static int adis16136_debugfs_init(struct iio_dev *indio_dev)
{
        struct adis16136 *adis16136 = iio_priv(indio_dev);
        struct dentry *d = iio_get_debugfs_dentry(indio_dev);

        debugfs_create_file_unsafe("serial_number", 0400,
                d, adis16136, &adis16136_serial_fops);
        debugfs_create_file_unsafe("product_id", 0400,
                d, adis16136, &adis16136_product_id_fops);
        debugfs_create_file_unsafe("flash_count", 0400,
                d, adis16136, &adis16136_flash_count_fops);

        return 0;
}

#else

static int adis16136_debugfs_init(struct iio_dev *indio_dev)
{
        return 0;
}

#endif

static int adis16136_set_freq(struct adis16136 *adis16136, unsigned int freq)
{
        unsigned int t;

        t = 32768 / freq;
        if (t < 0xf)
                t = 0xf;
        else if (t > 0xffff)
                t = 0xffff;
        else
                t--;

        return adis_write_reg_16(&adis16136->adis, ADIS16136_REG_SMPL_PRD, t);
}

static int __adis16136_get_freq(struct adis16136 *adis16136, unsigned int *freq)
{
        uint16_t t;
        int ret;

        ret = __adis_read_reg_16(&adis16136->adis, ADIS16136_REG_SMPL_PRD, &t);
        if (ret)
                return ret;

        *freq = 32768 / (t + 1);

        return 0;
}

static ssize_t adis16136_write_frequency(struct device *dev,
        struct device_attribute *attr, const char *buf, size_t len)
{
        struct iio_dev *indio_dev = dev_to_iio_dev(dev);
        struct adis16136 *adis16136 = iio_priv(indio_dev);
        unsigned int val;
        int ret;

        ret = kstrtouint(buf, 10, &val);
        if (ret)
                return ret;

        if (val == 0)
                return -EINVAL;

        ret = adis16136_set_freq(adis16136, val);

        return ret ? ret : len;
}

static ssize_t adis16136_read_frequency(struct device *dev,
        struct device_attribute *attr, char *buf)
{
        struct iio_dev *indio_dev = dev_to_iio_dev(dev);
        struct adis16136 *adis16136 = iio_priv(indio_dev);
        unsigned int freq;
        int ret;

        adis_dev_auto_lock(&adis16136->adis);
        ret = __adis16136_get_freq(adis16136, &freq);
        if (ret)
                return ret;

        return sysfs_emit(buf, "%d\n", freq);
}

static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR | S_IRUGO,
                                  adis16136_read_frequency,
                                  adis16136_write_frequency);

static const unsigned adis16136_3db_divisors[] = {
        [0] = 2, /* Special case */
        [1] = 6,
        [2] = 12,
        [3] = 25,
        [4] = 50,
        [5] = 100,
        [6] = 200,
        [7] = 200, /* Not a valid setting */
};

static int adis16136_set_filter(struct iio_dev *indio_dev, int val)
{
        struct adis16136 *adis16136 = iio_priv(indio_dev);
        unsigned int freq;
        int i, ret;

        adis_dev_auto_lock(&adis16136->adis);
        ret = __adis16136_get_freq(adis16136, &freq);
        if (ret)
                return ret;

        for (i = ARRAY_SIZE(adis16136_3db_divisors) - 1; i >= 1; i--) {
                if (freq / adis16136_3db_divisors[i] >= val)
                        break;
        }

        return __adis_write_reg_16(&adis16136->adis, ADIS16136_REG_AVG_CNT, i);
}

static int adis16136_get_filter(struct iio_dev *indio_dev, int *val)
{
        struct adis16136 *adis16136 = iio_priv(indio_dev);
        unsigned int freq;
        uint16_t val16;
        int ret;

        adis_dev_auto_lock(&adis16136->adis);

        ret = __adis_read_reg_16(&adis16136->adis, ADIS16136_REG_AVG_CNT,
                                 &val16);
        if (ret)
                return ret;

        ret = __adis16136_get_freq(adis16136, &freq);
        if (ret)
                return ret;

        *val = freq / adis16136_3db_divisors[val16 & 0x07];

        return IIO_VAL_INT;
}

static int adis16136_read_raw(struct iio_dev *indio_dev,
        const struct iio_chan_spec *chan, int *val, int *val2, long info)
{
        struct adis16136 *adis16136 = iio_priv(indio_dev);
        uint32_t val32;
        int ret;

        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 = adis16136->chip_info->precision;
                        *val2 = (adis16136->chip_info->fullscale << 16);
                        return IIO_VAL_FRACTIONAL;
                case IIO_TEMP:
                        *val = 10;
                        *val2 = 697000; /* 0.010697 degree Celsius */
                        return IIO_VAL_INT_PLUS_MICRO;
                default:
                        return -EINVAL;
                }
        case IIO_CHAN_INFO_CALIBBIAS:
                ret = adis_read_reg_32(&adis16136->adis,
                        ADIS16136_REG_GYRO_OFF2, &val32);
                if (ret)
                        return ret;

                *val = sign_extend32(val32, 31);

                return IIO_VAL_INT;
        case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
                return adis16136_get_filter(indio_dev, val);
        default:
                return -EINVAL;
        }
}

static int adis16136_write_raw(struct iio_dev *indio_dev,
        const struct iio_chan_spec *chan, int val, int val2, long info)
{
        struct adis16136 *adis16136 = iio_priv(indio_dev);

        switch (info) {
        case IIO_CHAN_INFO_CALIBBIAS:
                return adis_write_reg_32(&adis16136->adis,
                        ADIS16136_REG_GYRO_OFF2, val);
        case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
                return adis16136_set_filter(indio_dev, val);
        default:
                break;
        }

        return -EINVAL;
}

enum {
        ADIS16136_SCAN_GYRO,
        ADIS16136_SCAN_TEMP,
};

static const struct iio_chan_spec adis16136_channels[] = {
        {
                .type = IIO_ANGL_VEL,
                .modified = 1,
                .channel2 = IIO_MOD_X,
                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
                        BIT(IIO_CHAN_INFO_CALIBBIAS) |
                        BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
                .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),

                .address = ADIS16136_REG_GYRO_OUT2,
                .scan_index = ADIS16136_SCAN_GYRO,
                .scan_type = {
                        .sign = 's',
                        .realbits = 32,
                        .storagebits = 32,
                        .endianness = IIO_BE,
                },
        }, {
                .type = IIO_TEMP,
                .indexed = 1,
                .channel = 0,
                .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
                        BIT(IIO_CHAN_INFO_SCALE),
                .address = ADIS16136_REG_TEMP_OUT,
                .scan_index = ADIS16136_SCAN_TEMP,
                .scan_type = {
                        .sign = 's',
                        .realbits = 16,
                        .storagebits = 16,
                        .endianness = IIO_BE,
                },
        },
        IIO_CHAN_SOFT_TIMESTAMP(2),
};

static struct attribute *adis16136_attributes[] = {
        &iio_dev_attr_sampling_frequency.dev_attr.attr,
        NULL
};

static const struct attribute_group adis16136_attribute_group = {
        .attrs = adis16136_attributes,
};

static const struct iio_info adis16136_info = {
        .attrs = &adis16136_attribute_group,
        .read_raw = &adis16136_read_raw,
        .write_raw = &adis16136_write_raw,
        .update_scan_mode = adis_update_scan_mode,
        .debugfs_reg_access = adis_debugfs_reg_access,
};

static int adis16136_stop_device(struct iio_dev *indio_dev)
{
        struct adis16136 *adis16136 = iio_priv(indio_dev);
        int ret;

        ret = adis_write_reg_16(&adis16136->adis, ADIS16136_REG_SLP_CTRL, 0xff);
        if (ret)
                dev_err(&indio_dev->dev,
                        "Could not power down device: %d\n", ret);

        return ret;
}

static int adis16136_initial_setup(struct iio_dev *indio_dev)
{
        struct adis16136 *adis16136 = iio_priv(indio_dev);
        unsigned int device_id;
        uint16_t prod_id;
        int ret;

        ret = __adis_initial_startup(&adis16136->adis);
        if (ret)
                return ret;

        ret = adis_read_reg_16(&adis16136->adis, ADIS16136_REG_PROD_ID,
                &prod_id);
        if (ret)
                return ret;

        ret = sscanf(indio_dev->name, "adis%u\n", &device_id);
        if (ret != 1)
                return -EINVAL;

        if (prod_id != device_id)
                dev_warn(&indio_dev->dev, "Device ID(%u) and product ID(%u) do not match.",
                                device_id, prod_id);

        return 0;
}

static const char * const adis16136_status_error_msgs[] = {
        [ADIS16136_DIAG_STAT_FLASH_UPDATE_FAIL] = "Flash update failed",
        [ADIS16136_DIAG_STAT_SPI_FAIL] = "SPI failure",
        [ADIS16136_DIAG_STAT_SELF_TEST_FAIL] = "Self test error",
        [ADIS16136_DIAG_STAT_FLASH_CHKSUM_FAIL] = "Flash checksum error",
};

#define ADIS16136_DATA(_timeouts)                                       \
{                                                                       \
        .diag_stat_reg = ADIS16136_REG_DIAG_STAT,                       \
        .glob_cmd_reg = ADIS16136_REG_GLOB_CMD,                         \
        .msc_ctrl_reg = ADIS16136_REG_MSC_CTRL,                         \
        .self_test_reg = ADIS16136_REG_MSC_CTRL,                        \
        .self_test_mask = ADIS16136_MSC_CTRL_SELF_TEST,                 \
        .read_delay = 10,                                               \
        .write_delay = 10,                                              \
        .status_error_msgs = adis16136_status_error_msgs,               \
        .status_error_mask = BIT(ADIS16136_DIAG_STAT_FLASH_UPDATE_FAIL) |       \
                BIT(ADIS16136_DIAG_STAT_SPI_FAIL) |                     \
                BIT(ADIS16136_DIAG_STAT_SELF_TEST_FAIL) |               \
                BIT(ADIS16136_DIAG_STAT_FLASH_CHKSUM_FAIL),             \
        .timeouts = (_timeouts),                                        \
}

enum adis16136_id {
        ID_ADIS16133,
        ID_ADIS16135,
        ID_ADIS16136,
        ID_ADIS16137,
};

static const struct adis_timeout adis16133_timeouts = {
        .reset_ms = 75,
        .sw_reset_ms = 75,
        .self_test_ms = 50,
};

static const struct adis_timeout adis16136_timeouts = {
        .reset_ms = 128,
        .sw_reset_ms = 75,
        .self_test_ms = 245,
};

static const struct adis16136_chip_info adis16136_chip_info[] = {
        [ID_ADIS16133] = {
                .precision = IIO_DEGREE_TO_RAD(1200),
                .fullscale = 24000,
                .adis_data = ADIS16136_DATA(&adis16133_timeouts),
        },
        [ID_ADIS16135] = {
                .precision = IIO_DEGREE_TO_RAD(300),
                .fullscale = 24000,
                .adis_data = ADIS16136_DATA(&adis16133_timeouts),
        },
        [ID_ADIS16136] = {
                .precision = IIO_DEGREE_TO_RAD(450),
                .fullscale = 24623,
                .adis_data = ADIS16136_DATA(&adis16136_timeouts),
        },
        [ID_ADIS16137] = {
                .precision = IIO_DEGREE_TO_RAD(1000),
                .fullscale = 24609,
                .adis_data = ADIS16136_DATA(&adis16136_timeouts),
        },
};

static void adis16136_stop(void *data)
{
        adis16136_stop_device(data);
}

static int adis16136_probe(struct spi_device *spi)
{
        const struct spi_device_id *id = spi_get_device_id(spi);
        struct adis16136 *adis16136;
        struct iio_dev *indio_dev;
        const struct adis_data *adis16136_data;
        int ret;

        indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*adis16136));
        if (indio_dev == NULL)
                return -ENOMEM;

        spi_set_drvdata(spi, indio_dev);

        adis16136 = iio_priv(indio_dev);

        adis16136->chip_info = &adis16136_chip_info[id->driver_data];
        indio_dev->name = spi_get_device_id(spi)->name;
        indio_dev->channels = adis16136_channels;
        indio_dev->num_channels = ARRAY_SIZE(adis16136_channels);
        indio_dev->info = &adis16136_info;
        indio_dev->modes = INDIO_DIRECT_MODE;

        adis16136_data = &adis16136->chip_info->adis_data;

        ret = adis_init(&adis16136->adis, indio_dev, spi, adis16136_data);
        if (ret)
                return ret;

        ret = devm_adis_setup_buffer_and_trigger(&adis16136->adis, indio_dev, NULL);
        if (ret)
                return ret;

        ret = adis16136_initial_setup(indio_dev);
        if (ret)
                return ret;

        ret = devm_add_action_or_reset(&spi->dev, adis16136_stop, indio_dev);
        if (ret)
                return ret;

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

        adis16136_debugfs_init(indio_dev);

        return 0;
}

static const struct spi_device_id adis16136_ids[] = {
        { "adis16133", ID_ADIS16133 },
        { "adis16135", ID_ADIS16135 },
        { "adis16136", ID_ADIS16136 },
        { "adis16137", ID_ADIS16137 },
        { }
};
MODULE_DEVICE_TABLE(spi, adis16136_ids);

static struct spi_driver adis16136_driver = {
        .driver = {
                .name = "adis16136",
        },
        .id_table = adis16136_ids,
        .probe = adis16136_probe,
};
module_spi_driver(adis16136_driver);

MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
MODULE_DESCRIPTION("Analog Devices ADIS16133/ADIS16135/ADIS16136 gyroscope driver");
MODULE_LICENSE("GPL v2");
MODULE_IMPORT_NS("IIO_ADISLIB");