// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Hardware monitoring driver for PIM4006, PIM4328 and PIM4820
 *
 * Copyright (c) 2021 Flextronics International Sweden AB
 */

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

enum chips { pim4006, pim4328, pim4820 };

struct pim4328_data {
        enum chips id;
        struct pmbus_driver_info info;
};

#define to_pim4328_data(x)  container_of(x, struct pim4328_data, info)

/* PIM4006 and PIM4328 */
#define PIM4328_MFR_READ_VINA           0xd3
#define PIM4328_MFR_READ_VINB           0xd4

/* PIM4006 */
#define PIM4328_MFR_READ_IINA           0xd6
#define PIM4328_MFR_READ_IINB           0xd7
#define PIM4328_MFR_FET_CHECKSTATUS     0xd9

/* PIM4328 */
#define PIM4328_MFR_STATUS_BITS         0xd5

/* PIM4820 */
#define PIM4328_MFR_READ_STATUS         0xd0

static const struct i2c_device_id pim4328_id[] = {
        {"bmr455", pim4328},
        {"pim4006", pim4006},
        {"pim4106", pim4006},
        {"pim4206", pim4006},
        {"pim4306", pim4006},
        {"pim4328", pim4328},
        {"pim4406", pim4006},
        {"pim4820", pim4820},
        {}
};
MODULE_DEVICE_TABLE(i2c, pim4328_id);

static int pim4328_read_word_data(struct i2c_client *client, int page,
                                  int phase, int reg)
{
        int ret;

        if (page > 0)
                return -ENXIO;

        if (phase == 0xff)
                return -ENODATA;

        switch (reg) {
        case PMBUS_READ_VIN:
                ret = pmbus_read_word_data(client, page, phase,
                                           phase == 0 ? PIM4328_MFR_READ_VINA
                                                      : PIM4328_MFR_READ_VINB);
                break;
        case PMBUS_READ_IIN:
                ret = pmbus_read_word_data(client, page, phase,
                                           phase == 0 ? PIM4328_MFR_READ_IINA
                                                      : PIM4328_MFR_READ_IINB);
                break;
        default:
                ret = -ENODATA;
        }

        return ret;
}

static int pim4328_read_byte_data(struct i2c_client *client, int page, int reg)
{
        const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
        struct pim4328_data *data = to_pim4328_data(info);
        int ret, status;

        if (page > 0)
                return -ENXIO;

        switch (reg) {
        case PMBUS_STATUS_BYTE:
                ret = pmbus_read_byte_data(client, page, PMBUS_STATUS_BYTE);
                if (ret < 0)
                        return ret;
                if (data->id == pim4006) {
                        status = pmbus_read_word_data(client, page, 0xff,
                                                      PIM4328_MFR_FET_CHECKSTATUS);
                        if (status < 0)
                                return status;
                        if (status & 0x0630) /* Input UV */
                                ret |= PB_STATUS_VIN_UV;
                } else if (data->id == pim4328) {
                        status = pmbus_read_byte_data(client, page,
                                                      PIM4328_MFR_STATUS_BITS);
                        if (status < 0)
                                return status;
                        if (status & 0x04) /* Input UV */
                                ret |= PB_STATUS_VIN_UV;
                        if (status & 0x40) /* Output UV */
                                ret |= PB_STATUS_NONE_ABOVE;
                } else if (data->id == pim4820) {
                        status = pmbus_read_byte_data(client, page,
                                                      PIM4328_MFR_READ_STATUS);
                        if (status < 0)
                                return status;
                        if (status & 0x05) /* Input OV or OC */
                                ret |= PB_STATUS_NONE_ABOVE;
                        if (status & 0x1a) /* Input UV */
                                ret |= PB_STATUS_VIN_UV;
                        if (status & 0x40) /* OT */
                                ret |= PB_STATUS_TEMPERATURE;
                }
                break;
        default:
                ret = -ENODATA;
        }

        return ret;
}

static int pim4328_probe(struct i2c_client *client)
{
        int status;
        u8 device_id[I2C_SMBUS_BLOCK_MAX + 1];
        const struct i2c_device_id *mid;
        struct pim4328_data *data;
        struct pmbus_driver_info *info;
        struct pmbus_platform_data *pdata;
        struct device *dev = &client->dev;

        if (!i2c_check_functionality(client->adapter,
                                     I2C_FUNC_SMBUS_READ_BYTE_DATA
                                     | I2C_FUNC_SMBUS_BLOCK_DATA))
                return -ENODEV;

        data = devm_kzalloc(&client->dev, sizeof(struct pim4328_data),
                            GFP_KERNEL);
        if (!data)
                return -ENOMEM;

        status = i2c_smbus_read_block_data(client, PMBUS_MFR_MODEL, device_id);
        if (status < 0) {
                dev_err(&client->dev, "Failed to read Manufacturer Model\n");
                return status;
        }
        for (mid = pim4328_id; mid->name[0]; mid++) {
                if (!strncasecmp(mid->name, device_id, strlen(mid->name)))
                        break;
        }
        if (!mid->name[0]) {
                dev_err(&client->dev, "Unsupported device\n");
                return -ENODEV;
        }

        if (strcmp(client->name, mid->name))
                dev_notice(&client->dev,
                           "Device mismatch: Configured %s, detected %s\n",
                           client->name, mid->name);

        data->id = mid->driver_data;
        info = &data->info;
        info->pages = 1;
        info->read_byte_data = pim4328_read_byte_data;
        info->read_word_data = pim4328_read_word_data;

        pdata = devm_kzalloc(dev, sizeof(struct pmbus_platform_data),
                             GFP_KERNEL);
        if (!pdata)
                return -ENOMEM;
        dev->platform_data = pdata;
        pdata->flags = PMBUS_NO_CAPABILITY | PMBUS_NO_WRITE_PROTECT;

        switch (data->id) {
        case pim4006:
                info->phases[0] = 2;
                info->func[0] = PMBUS_PHASE_VIRTUAL | PMBUS_HAVE_VIN
                        | PMBUS_HAVE_TEMP | PMBUS_HAVE_IOUT;
                info->pfunc[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_IIN;
                info->pfunc[1] = PMBUS_HAVE_VIN | PMBUS_HAVE_IIN;
                break;
        case pim4328:
                info->phases[0] = 2;
                info->func[0] = PMBUS_PHASE_VIRTUAL
                        | PMBUS_HAVE_VCAP | PMBUS_HAVE_VIN
                        | PMBUS_HAVE_TEMP | PMBUS_HAVE_IOUT;
                info->pfunc[0] = PMBUS_HAVE_VIN;
                info->pfunc[1] = PMBUS_HAVE_VIN;
                info->format[PSC_VOLTAGE_IN] = direct;
                info->format[PSC_TEMPERATURE] = direct;
                info->format[PSC_CURRENT_OUT] = direct;
                pdata->flags |= PMBUS_USE_COEFFICIENTS_CMD;
                break;
        case pim4820:
                info->func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_TEMP
                        | PMBUS_HAVE_IIN;
                info->format[PSC_VOLTAGE_IN] = direct;
                info->format[PSC_TEMPERATURE] = direct;
                info->format[PSC_CURRENT_IN] = direct;
                pdata->flags |= PMBUS_USE_COEFFICIENTS_CMD;
                break;
        default:
                return -ENODEV;
        }

        return pmbus_do_probe(client, info);
}

static struct i2c_driver pim4328_driver = {
        .driver = {
                   .name = "pim4328",
                   },
        .probe = pim4328_probe,
        .id_table = pim4328_id,
};

module_i2c_driver(pim4328_driver);

MODULE_AUTHOR("Erik Rosen <erik.rosen@metormote.com>");
MODULE_DESCRIPTION("PMBus driver for PIM4006, PIM4328, PIM4820 power interface modules");
MODULE_LICENSE("GPL");
MODULE_IMPORT_NS("PMBUS");