// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Hardware monitoring driver for LM25056 / LM25066 / LM5064 / LM5066
 *
 * Copyright (c) 2011 Ericsson AB.
 * Copyright (c) 2013 Guenter Roeck
 */

#include <linux/bitops.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/log2.h>
#include <linux/of.h>
#include "pmbus.h"

enum chips { lm25056, lm25066, lm5064, lm5066, lm5066i };

#define LM25066_READ_VAUX               0xd0
#define LM25066_MFR_READ_IIN            0xd1
#define LM25066_MFR_READ_PIN            0xd2
#define LM25066_MFR_IIN_OC_WARN_LIMIT   0xd3
#define LM25066_MFR_PIN_OP_WARN_LIMIT   0xd4
#define LM25066_READ_PIN_PEAK           0xd5
#define LM25066_CLEAR_PIN_PEAK          0xd6
#define LM25066_DEVICE_SETUP            0xd9
#define LM25066_READ_AVG_VIN            0xdc
#define LM25066_SAMPLES_FOR_AVG         0xdb
#define LM25066_READ_AVG_VOUT           0xdd
#define LM25066_READ_AVG_IIN            0xde
#define LM25066_READ_AVG_PIN            0xdf

#define LM25066_DEV_SETUP_CL            BIT(4)  /* Current limit */

#define LM25066_SAMPLES_FOR_AVG_MAX     4096

/* LM25056 only */

#define LM25056_VAUX_OV_WARN_LIMIT      0xe3
#define LM25056_VAUX_UV_WARN_LIMIT      0xe4

#define LM25056_MFR_STS_VAUX_OV_WARN    BIT(1)
#define LM25056_MFR_STS_VAUX_UV_WARN    BIT(0)

struct __coeff {
        short m, b, R;
};

#define PSC_CURRENT_IN_L        (PSC_NUM_CLASSES)
#define PSC_POWER_L             (PSC_NUM_CLASSES + 1)

static const struct __coeff lm25066_coeff[][PSC_NUM_CLASSES + 2] = {
        [lm25056] = {
                [PSC_VOLTAGE_IN] = {
                        .m = 16296,
                        .b = 1343,
                        .R = -2,
                },
                [PSC_CURRENT_IN] = {
                        .m = 13797,
                        .b = -1833,
                        .R = -2,
                },
                [PSC_CURRENT_IN_L] = {
                        .m = 6726,
                        .b = -537,
                        .R = -2,
                },
                [PSC_POWER] = {
                        .m = 5501,
                        .b = -2908,
                        .R = -3,
                },
                [PSC_POWER_L] = {
                        .m = 26882,
                        .b = -5646,
                        .R = -4,
                },
                [PSC_TEMPERATURE] = {
                        .m = 1580,
                        .b = -14500,
                        .R = -2,
                },
        },
        [lm25066] = {
                [PSC_VOLTAGE_IN] = {
                        .m = 22070,
                        .b = -1800,
                        .R = -2,
                },
                [PSC_VOLTAGE_OUT] = {
                        .m = 22070,
                        .b = -1800,
                        .R = -2,
                },
                [PSC_CURRENT_IN] = {
                        .m = 13661,
                        .b = -5200,
                        .R = -2,
                },
                [PSC_CURRENT_IN_L] = {
                        .m = 6854,
                        .b = -3100,
                        .R = -2,
                },
                [PSC_POWER] = {
                        .m = 736,
                        .b = -3300,
                        .R = -2,
                },
                [PSC_POWER_L] = {
                        .m = 369,
                        .b = -1900,
                        .R = -2,
                },
                [PSC_TEMPERATURE] = {
                        .m = 16,
                },
        },
        [lm5064] = {
                [PSC_VOLTAGE_IN] = {
                        .m = 4611,
                        .b = -642,
                        .R = -2,
                },
                [PSC_VOLTAGE_OUT] = {
                        .m = 4621,
                        .b = 423,
                        .R = -2,
                },
                [PSC_CURRENT_IN] = {
                        .m = 10742,
                        .b = 1552,
                        .R = -2,
                },
                [PSC_CURRENT_IN_L] = {
                        .m = 5456,
                        .b = 2118,
                        .R = -2,
                },
                [PSC_POWER] = {
                        .m = 1204,
                        .b = 8524,
                        .R = -3,
                },
                [PSC_POWER_L] = {
                        .m = 612,
                        .b = 11202,
                        .R = -3,
                },
                [PSC_TEMPERATURE] = {
                        .m = 16,
                },
        },
        [lm5066] = {
                [PSC_VOLTAGE_IN] = {
                        .m = 4587,
                        .b = -1200,
                        .R = -2,
                },
                [PSC_VOLTAGE_OUT] = {
                        .m = 4587,
                        .b = -2400,
                        .R = -2,
                },
                [PSC_CURRENT_IN] = {
                        .m = 10753,
                        .b = -1200,
                        .R = -2,
                },
                [PSC_CURRENT_IN_L] = {
                        .m = 5405,
                        .b = -600,
                        .R = -2,
                },
                [PSC_POWER] = {
                        .m = 1204,
                        .b = -6000,
                        .R = -3,
                },
                [PSC_POWER_L] = {
                        .m = 605,
                        .b = -8000,
                        .R = -3,
                },
                [PSC_TEMPERATURE] = {
                        .m = 16,
                },
        },
        [lm5066i] = {
                [PSC_VOLTAGE_IN] = {
                        .m = 4617,
                        .b = -140,
                        .R = -2,
                },
                [PSC_VOLTAGE_OUT] = {
                        .m = 4602,
                        .b = 500,
                        .R = -2,
                },
                [PSC_CURRENT_IN] = {
                        .m = 15076,
                        .b = -504,
                        .R = -2,
                },
                [PSC_CURRENT_IN_L] = {
                        .m = 7645,
                        .b = 100,
                        .R = -2,
                },
                [PSC_POWER] = {
                        .m = 1701,
                        .b = -4000,
                        .R = -3,
                },
                [PSC_POWER_L] = {
                        .m = 861,
                        .b = -965,
                        .R = -3,
                },
                [PSC_TEMPERATURE] = {
                        .m = 16,
                },
        },
};

struct lm25066_data {
        int id;
        u16 rlimit;                     /* Maximum register value */
        struct pmbus_driver_info info;
};

#define to_lm25066_data(x)  container_of(x, struct lm25066_data, info)

static int lm25066_read_word_data(struct i2c_client *client, int page,
                                  int phase, int reg)
{
        const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
        const struct lm25066_data *data = to_lm25066_data(info);
        int ret;

        switch (reg) {
        case PMBUS_VIRT_READ_VMON:
                ret = pmbus_read_word_data(client, 0, 0xff, LM25066_READ_VAUX);
                if (ret < 0)
                        break;
                /* Adjust returned value to match VIN coefficients */
                switch (data->id) {
                case lm25056:
                        /* VIN: 6.14 mV VAUX: 293 uV LSB */
                        ret = DIV_ROUND_CLOSEST(ret * 293, 6140);
                        break;
                case lm25066:
                        /* VIN: 4.54 mV VAUX: 283.2 uV LSB */
                        ret = DIV_ROUND_CLOSEST(ret * 2832, 45400);
                        break;
                case lm5064:
                        /* VIN: 4.53 mV VAUX: 700 uV LSB */
                        ret = DIV_ROUND_CLOSEST(ret * 70, 453);
                        break;
                case lm5066:
                case lm5066i:
                        /* VIN: 2.18 mV VAUX: 725 uV LSB */
                        ret = DIV_ROUND_CLOSEST(ret * 725, 2180);
                        break;
                }
                break;
        case PMBUS_READ_IIN:
                ret = pmbus_read_word_data(client, 0, 0xff,
                                           LM25066_MFR_READ_IIN);
                break;
        case PMBUS_READ_PIN:
                ret = pmbus_read_word_data(client, 0, 0xff,
                                           LM25066_MFR_READ_PIN);
                break;
        case PMBUS_IIN_OC_WARN_LIMIT:
                ret = pmbus_read_word_data(client, 0, 0xff,
                                           LM25066_MFR_IIN_OC_WARN_LIMIT);
                break;
        case PMBUS_PIN_OP_WARN_LIMIT:
                ret = pmbus_read_word_data(client, 0, 0xff,
                                           LM25066_MFR_PIN_OP_WARN_LIMIT);
                break;
        case PMBUS_VIRT_READ_VIN_AVG:
                ret = pmbus_read_word_data(client, 0, 0xff,
                                           LM25066_READ_AVG_VIN);
                break;
        case PMBUS_VIRT_READ_VOUT_AVG:
                ret = pmbus_read_word_data(client, 0, 0xff,
                                           LM25066_READ_AVG_VOUT);
                break;
        case PMBUS_VIRT_READ_IIN_AVG:
                ret = pmbus_read_word_data(client, 0, 0xff,
                                           LM25066_READ_AVG_IIN);
                break;
        case PMBUS_VIRT_READ_PIN_AVG:
                ret = pmbus_read_word_data(client, 0, 0xff,
                                           LM25066_READ_AVG_PIN);
                break;
        case PMBUS_VIRT_READ_PIN_MAX:
                ret = pmbus_read_word_data(client, 0, 0xff,
                                           LM25066_READ_PIN_PEAK);
                break;
        case PMBUS_VIRT_RESET_PIN_HISTORY:
                ret = 0;
                break;
        case PMBUS_VIRT_SAMPLES:
                ret = pmbus_read_byte_data(client, 0, LM25066_SAMPLES_FOR_AVG);
                if (ret < 0)
                        break;
                ret = 1 << ret;
                break;
        default:
                ret = -ENODATA;
                break;
        }
        return ret;
}

static int lm25056_read_word_data(struct i2c_client *client, int page,
                                  int phase, int reg)
{
        int ret;

        switch (reg) {
        case PMBUS_VIRT_VMON_UV_WARN_LIMIT:
                ret = pmbus_read_word_data(client, 0, 0xff,
                                           LM25056_VAUX_UV_WARN_LIMIT);
                if (ret < 0)
                        break;
                /* Adjust returned value to match VIN coefficients */
                ret = DIV_ROUND_CLOSEST(ret * 293, 6140);
                break;
        case PMBUS_VIRT_VMON_OV_WARN_LIMIT:
                ret = pmbus_read_word_data(client, 0, 0xff,
                                           LM25056_VAUX_OV_WARN_LIMIT);
                if (ret < 0)
                        break;
                /* Adjust returned value to match VIN coefficients */
                ret = DIV_ROUND_CLOSEST(ret * 293, 6140);
                break;
        default:
                ret = lm25066_read_word_data(client, page, phase, reg);
                break;
        }
        return ret;
}

static int lm25056_read_byte_data(struct i2c_client *client, int page, int reg)
{
        int ret, s;

        switch (reg) {
        case PMBUS_VIRT_STATUS_VMON:
                ret = pmbus_read_byte_data(client, 0,
                                           PMBUS_STATUS_MFR_SPECIFIC);
                if (ret < 0)
                        break;
                s = 0;
                if (ret & LM25056_MFR_STS_VAUX_UV_WARN)
                        s |= PB_VOLTAGE_UV_WARNING;
                if (ret & LM25056_MFR_STS_VAUX_OV_WARN)
                        s |= PB_VOLTAGE_OV_WARNING;
                ret = s;
                break;
        default:
                ret = -ENODATA;
                break;
        }
        return ret;
}

static int lm25066_write_word_data(struct i2c_client *client, int page, int reg,
                                   u16 word)
{
        const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
        const struct lm25066_data *data = to_lm25066_data(info);
        int ret;

        switch (reg) {
        case PMBUS_POUT_OP_FAULT_LIMIT:
        case PMBUS_POUT_OP_WARN_LIMIT:
        case PMBUS_VOUT_UV_WARN_LIMIT:
        case PMBUS_OT_FAULT_LIMIT:
        case PMBUS_OT_WARN_LIMIT:
        case PMBUS_IIN_OC_FAULT_LIMIT:
        case PMBUS_VIN_UV_WARN_LIMIT:
        case PMBUS_VIN_UV_FAULT_LIMIT:
        case PMBUS_VIN_OV_FAULT_LIMIT:
        case PMBUS_VIN_OV_WARN_LIMIT:
                word = ((s16)word < 0) ? 0 : clamp_val(word, 0, data->rlimit);
                ret = pmbus_write_word_data(client, 0, reg, word);
                break;
        case PMBUS_IIN_OC_WARN_LIMIT:
                word = ((s16)word < 0) ? 0 : clamp_val(word, 0, data->rlimit);
                ret = pmbus_write_word_data(client, 0,
                                            LM25066_MFR_IIN_OC_WARN_LIMIT,
                                            word);
                break;
        case PMBUS_PIN_OP_WARN_LIMIT:
                word = ((s16)word < 0) ? 0 : clamp_val(word, 0, data->rlimit);
                ret = pmbus_write_word_data(client, 0,
                                            LM25066_MFR_PIN_OP_WARN_LIMIT,
                                            word);
                break;
        case PMBUS_VIRT_VMON_UV_WARN_LIMIT:
                /* Adjust from VIN coefficients (for LM25056) */
                word = DIV_ROUND_CLOSEST((int)word * 6140, 293);
                word = ((s16)word < 0) ? 0 : clamp_val(word, 0, data->rlimit);
                ret = pmbus_write_word_data(client, 0,
                                            LM25056_VAUX_UV_WARN_LIMIT, word);
                break;
        case PMBUS_VIRT_VMON_OV_WARN_LIMIT:
                /* Adjust from VIN coefficients (for LM25056) */
                word = DIV_ROUND_CLOSEST((int)word * 6140, 293);
                word = ((s16)word < 0) ? 0 : clamp_val(word, 0, data->rlimit);
                ret = pmbus_write_word_data(client, 0,
                                            LM25056_VAUX_OV_WARN_LIMIT, word);
                break;
        case PMBUS_VIRT_RESET_PIN_HISTORY:
                ret = pmbus_write_byte(client, 0, LM25066_CLEAR_PIN_PEAK);
                break;
        case PMBUS_VIRT_SAMPLES:
                word = clamp_val(word, 1, LM25066_SAMPLES_FOR_AVG_MAX);
                ret = pmbus_write_byte_data(client, 0, LM25066_SAMPLES_FOR_AVG,
                                            ilog2(word));
                break;
        default:
                ret = -ENODATA;
                break;
        }
        return ret;
}

#if IS_ENABLED(CONFIG_SENSORS_LM25066_REGULATOR)
static const struct regulator_desc lm25066_reg_desc[] = {
        PMBUS_REGULATOR_ONE_NODE("vout"),
};
#endif

static const struct i2c_device_id lm25066_id[] = {
        {"lm25056", lm25056},
        {"lm25066", lm25066},
        {"lm5064", lm5064},
        {"lm5066", lm5066},
        {"lm5066i", lm5066i},
        { }
};
MODULE_DEVICE_TABLE(i2c, lm25066_id);

static const struct of_device_id __maybe_unused lm25066_of_match[] = {
        { .compatible = "ti,lm25056", .data = (void *)lm25056, },
        { .compatible = "ti,lm25066", .data = (void *)lm25066, },
        { .compatible = "ti,lm5064",  .data = (void *)lm5064,  },
        { .compatible = "ti,lm5066",  .data = (void *)lm5066,  },
        { .compatible = "ti,lm5066i", .data = (void *)lm5066i, },
        { },
};
MODULE_DEVICE_TABLE(of, lm25066_of_match);

static int lm25066_probe(struct i2c_client *client)
{
        int config;
        u32 shunt;
        struct lm25066_data *data;
        struct pmbus_driver_info *info;
        const struct __coeff *coeff;

        if (!i2c_check_functionality(client->adapter,
                                     I2C_FUNC_SMBUS_READ_BYTE_DATA))
                return -ENODEV;

        data = devm_kzalloc(&client->dev, sizeof(struct lm25066_data),
                            GFP_KERNEL);
        if (!data)
                return -ENOMEM;

        config = i2c_smbus_read_byte_data(client, LM25066_DEVICE_SETUP);
        if (config < 0)
                return config;

        data->id = (enum chips)(unsigned long)i2c_get_match_data(client);

        info = &data->info;

        info->pages = 1;
        info->format[PSC_VOLTAGE_IN] = direct;
        info->format[PSC_VOLTAGE_OUT] = direct;
        info->format[PSC_CURRENT_IN] = direct;
        info->format[PSC_TEMPERATURE] = direct;
        info->format[PSC_POWER] = direct;

        info->func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VMON
          | PMBUS_HAVE_PIN | PMBUS_HAVE_IIN | PMBUS_HAVE_STATUS_INPUT
          | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP | PMBUS_HAVE_SAMPLES;

        if (data->id == lm25056) {
                info->func[0] |= PMBUS_HAVE_STATUS_VMON;
                info->read_word_data = lm25056_read_word_data;
                info->read_byte_data = lm25056_read_byte_data;
                data->rlimit = 0x0fff;
        } else {
                info->func[0] |= PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT;
                info->read_word_data = lm25066_read_word_data;
                data->rlimit = 0x0fff;
        }
        info->write_word_data = lm25066_write_word_data;

        coeff = &lm25066_coeff[data->id][0];
        info->m[PSC_TEMPERATURE] = coeff[PSC_TEMPERATURE].m;
        info->b[PSC_TEMPERATURE] = coeff[PSC_TEMPERATURE].b;
        info->R[PSC_TEMPERATURE] = coeff[PSC_TEMPERATURE].R;
        info->m[PSC_VOLTAGE_IN] = coeff[PSC_VOLTAGE_IN].m;
        info->b[PSC_VOLTAGE_IN] = coeff[PSC_VOLTAGE_IN].b;
        info->R[PSC_VOLTAGE_IN] = coeff[PSC_VOLTAGE_IN].R;
        info->m[PSC_VOLTAGE_OUT] = coeff[PSC_VOLTAGE_OUT].m;
        info->b[PSC_VOLTAGE_OUT] = coeff[PSC_VOLTAGE_OUT].b;
        info->R[PSC_VOLTAGE_OUT] = coeff[PSC_VOLTAGE_OUT].R;
        info->R[PSC_CURRENT_IN] = coeff[PSC_CURRENT_IN].R;
        info->R[PSC_POWER] = coeff[PSC_POWER].R;
        if (config & LM25066_DEV_SETUP_CL) {
                info->m[PSC_CURRENT_IN] = coeff[PSC_CURRENT_IN_L].m;
                info->b[PSC_CURRENT_IN] = coeff[PSC_CURRENT_IN_L].b;
                info->m[PSC_POWER] = coeff[PSC_POWER_L].m;
                info->b[PSC_POWER] = coeff[PSC_POWER_L].b;
        } else {
                info->m[PSC_CURRENT_IN] = coeff[PSC_CURRENT_IN].m;
                info->b[PSC_CURRENT_IN] = coeff[PSC_CURRENT_IN].b;
                info->m[PSC_POWER] = coeff[PSC_POWER].m;
                info->b[PSC_POWER] = coeff[PSC_POWER].b;
        }

        /*
         * Values in the TI datasheets are normalized for a 1mOhm sense
         * resistor; assume that unless DT specifies a value explicitly.
         */
        if (of_property_read_u32(client->dev.of_node, "shunt-resistor-micro-ohms", &shunt))
                shunt = 1000;

        info->m[PSC_CURRENT_IN] = info->m[PSC_CURRENT_IN] * shunt / 1000;
        info->m[PSC_POWER] = info->m[PSC_POWER] * shunt / 1000;

#if IS_ENABLED(CONFIG_SENSORS_LM25066_REGULATOR)
        /* LM25056 doesn't support OPERATION */
        if (data->id != lm25056) {
                info->num_regulators = ARRAY_SIZE(lm25066_reg_desc);
                info->reg_desc = lm25066_reg_desc;
        }
#endif

        return pmbus_do_probe(client, info);
}

/* This is the driver that will be inserted */
static struct i2c_driver lm25066_driver = {
        .driver = {
                   .name = "lm25066",
                   .of_match_table = of_match_ptr(lm25066_of_match),
        },
        .probe = lm25066_probe,
        .id_table = lm25066_id,
};

module_i2c_driver(lm25066_driver);

MODULE_AUTHOR("Guenter Roeck");
MODULE_DESCRIPTION("PMBus driver for LM25066 and compatible chips");
MODULE_LICENSE("GPL");
MODULE_IMPORT_NS("PMBUS");