// SPDX-License-Identifier: GPL-2.0+
/*
 * Hardware monitoring driver for Vicor PLI1209BC Digital Supervisor
 *
 * Copyright (c) 2022 9elements GmbH
 */

#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/pmbus.h>
#include <linux/regulator/driver.h>
#include "pmbus.h"

/*
 * The capability command is only supported at page 0. Probing the device while
 * the page register is set to 1 will falsely enable PEC support. Disable
 * capability probing accordingly, since the PLI1209BC does not have any
 * additional capabilities.
 */
static struct pmbus_platform_data pli1209bc_plat_data = {
        .flags = PMBUS_NO_CAPABILITY,
};

static int pli1209bc_read_word_data(struct i2c_client *client, int page,
                                    int phase, int reg)
{
        int data;

        switch (reg) {
        /* PMBUS_READ_POUT uses a direct format with R=0 */
        case PMBUS_READ_POUT:
                data = pmbus_read_word_data(client, page, phase, reg);
                if (data < 0)
                        return data;
                data = sign_extend32(data, 15) * 10;
                return clamp_val(data, -32768, 32767) & 0xffff;
        /*
         * PMBUS_READ_VOUT and PMBUS_READ_TEMPERATURE_1 return invalid data
         * when the BCM is turned off. Since it is not possible to return
         * ENODATA error, return zero instead.
         */
        case PMBUS_READ_VOUT:
        case PMBUS_READ_TEMPERATURE_1:
                data = pmbus_read_word_data(client, page, phase,
                                            PMBUS_STATUS_WORD);
                if (data < 0)
                        return data;
                if (data & PB_STATUS_POWER_GOOD_N)
                        return 0;
                return pmbus_read_word_data(client, page, phase, reg);
        default:
                return -ENODATA;
        }
}

#if IS_ENABLED(CONFIG_SENSORS_PLI1209BC_REGULATOR)
static const struct regulator_desc pli1209bc_reg_desc = {
        .name = "vout2",
        .id = 1,
        .of_match = of_match_ptr("vout2"),
        .regulators_node = of_match_ptr("regulators"),
        .ops = &pmbus_regulator_ops,
        .type = REGULATOR_VOLTAGE,
        .owner = THIS_MODULE,
};
#endif

static struct pmbus_driver_info pli1209bc_info = {
        .pages = 2,
        .format[PSC_VOLTAGE_IN] = direct,
        .format[PSC_VOLTAGE_OUT] = direct,
        .format[PSC_CURRENT_IN] = direct,
        .format[PSC_CURRENT_OUT] = direct,
        .format[PSC_POWER] = direct,
        .format[PSC_TEMPERATURE] = direct,
        .m[PSC_VOLTAGE_IN] = 1,
        .b[PSC_VOLTAGE_IN] = 0,
        .R[PSC_VOLTAGE_IN] = 1,
        .m[PSC_VOLTAGE_OUT] = 1,
        .b[PSC_VOLTAGE_OUT] = 0,
        .R[PSC_VOLTAGE_OUT] = 1,
        .m[PSC_CURRENT_IN] = 1,
        .b[PSC_CURRENT_IN] = 0,
        .R[PSC_CURRENT_IN] = 3,
        .m[PSC_CURRENT_OUT] = 1,
        .b[PSC_CURRENT_OUT] = 0,
        .R[PSC_CURRENT_OUT] = 2,
        .m[PSC_POWER] = 1,
        .b[PSC_POWER] = 0,
        .R[PSC_POWER] = 1,
        .m[PSC_TEMPERATURE] = 1,
        .b[PSC_TEMPERATURE] = 0,
        .R[PSC_TEMPERATURE] = 0,
        /*
         * Page 0 sums up all attributes except voltage readings.
         * The pli1209 digital supervisor only contains a single BCM, making
         * page 0 redundant.
         */
        .func[1] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT
            | PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT
            | PMBUS_HAVE_PIN | PMBUS_HAVE_POUT
            | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP
            | PMBUS_HAVE_STATUS_IOUT | PMBUS_HAVE_STATUS_INPUT,
        .read_word_data = pli1209bc_read_word_data,
        .write_delay = 250,
#if IS_ENABLED(CONFIG_SENSORS_PLI1209BC_REGULATOR)
        .num_regulators = 1,
        .reg_desc = &pli1209bc_reg_desc,
#endif
};

static int pli1209bc_probe(struct i2c_client *client)
{
        client->dev.platform_data = &pli1209bc_plat_data;
        return pmbus_do_probe(client, &pli1209bc_info);
}

static const struct i2c_device_id pli1209bc_id[] = {
        {"pli1209bc"},
        {}
};

MODULE_DEVICE_TABLE(i2c, pli1209bc_id);

#ifdef CONFIG_OF
static const struct of_device_id pli1209bc_of_match[] = {
        { .compatible = "vicor,pli1209bc" },
        { },
};
MODULE_DEVICE_TABLE(of, pli1209bc_of_match);
#endif

static struct i2c_driver pli1209bc_driver = {
        .driver = {
                   .name = "pli1209bc",
                   .of_match_table = of_match_ptr(pli1209bc_of_match),
                   },
        .probe = pli1209bc_probe,
        .id_table = pli1209bc_id,
};

module_i2c_driver(pli1209bc_driver);

MODULE_AUTHOR("Marcello Sylvester Bauer <sylv@sylv.io>");
MODULE_DESCRIPTION("PMBus driver for Vicor PLI1209BC");
MODULE_LICENSE("GPL");
MODULE_IMPORT_NS("PMBUS");