root/drivers/hwmon/pmbus/q54sj108a2.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Driver for Delta modules, Q54SJ108A2 series 1/4 Brick DC/DC
 * Regulated Power Module
 *
 * Copyright 2020 Delta LLC.
 */

#include <linux/debugfs.h>
#include <linux/hex.h>
#include <linux/i2c.h>
#include <linux/kstrtox.h>
#include <linux/module.h>
#include <linux/of.h>
#include "pmbus.h"

#define STORE_DEFAULT_ALL               0x11
#define ERASE_BLACKBOX_DATA             0xD1
#define READ_HISTORY_EVENT_NUMBER       0xD2
#define READ_HISTORY_EVENTS             0xE0
#define SET_HISTORY_EVENT_OFFSET        0xE1
#define PMBUS_FLASH_KEY_WRITE           0xEC

enum chips {
        q54sj108a2
};

enum {
        Q54SJ108A2_DEBUGFS_OPERATION = 0,
        Q54SJ108A2_DEBUGFS_CLEARFAULT,
        Q54SJ108A2_DEBUGFS_WRITEPROTECT,
        Q54SJ108A2_DEBUGFS_STOREDEFAULT,
        Q54SJ108A2_DEBUGFS_VOOV_RESPONSE,
        Q54SJ108A2_DEBUGFS_IOOC_RESPONSE,
        Q54SJ108A2_DEBUGFS_PMBUS_VERSION,
        Q54SJ108A2_DEBUGFS_MFR_ID,
        Q54SJ108A2_DEBUGFS_MFR_MODEL,
        Q54SJ108A2_DEBUGFS_MFR_REVISION,
        Q54SJ108A2_DEBUGFS_MFR_LOCATION,
        Q54SJ108A2_DEBUGFS_BLACKBOX_ERASE,
        Q54SJ108A2_DEBUGFS_BLACKBOX_READ_OFFSET,
        Q54SJ108A2_DEBUGFS_BLACKBOX_SET_OFFSET,
        Q54SJ108A2_DEBUGFS_BLACKBOX_READ,
        Q54SJ108A2_DEBUGFS_FLASH_KEY,
        Q54SJ108A2_DEBUGFS_NUM_ENTRIES
};

struct q54sj108a2_data {
        enum chips chip;
        struct i2c_client *client;

        int debugfs_entries[Q54SJ108A2_DEBUGFS_NUM_ENTRIES];
};

#define to_psu(x, y) container_of((x), struct q54sj108a2_data, debugfs_entries[(y)])

static struct pmbus_driver_info q54sj108a2_info[] = {
        [q54sj108a2] = {
                .pages = 1,

                /* Source : Delta Q54SJ108A2 */
                .format[PSC_TEMPERATURE] = linear,
                .format[PSC_VOLTAGE_IN] = linear,
                .format[PSC_CURRENT_OUT] = linear,

                .func[0] = PMBUS_HAVE_VIN |
                PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT |
                PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT |
                PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP |
                PMBUS_HAVE_STATUS_INPUT,
        },
};

static ssize_t q54sj108a2_debugfs_read(struct file *file, char __user *buf,
                                       size_t count, loff_t *ppos)
{
        int rc;
        int *idxp = file->private_data;
        int idx = *idxp;
        struct q54sj108a2_data *psu = to_psu(idxp, idx);
        char data[I2C_SMBUS_BLOCK_MAX + 2] = { 0 };
        char data_char[I2C_SMBUS_BLOCK_MAX * 2 + 2] = { 0 };
        char *out = data;
        char *res;

        switch (idx) {
        case Q54SJ108A2_DEBUGFS_OPERATION:
                rc = i2c_smbus_read_byte_data(psu->client, PMBUS_OPERATION);
                if (rc < 0)
                        return rc;

                rc = snprintf(data, 3, "%02x", rc);
                break;
        case Q54SJ108A2_DEBUGFS_WRITEPROTECT:
                rc = i2c_smbus_read_byte_data(psu->client, PMBUS_WRITE_PROTECT);
                if (rc < 0)
                        return rc;

                rc = snprintf(data, 3, "%02x", rc);
                break;
        case Q54SJ108A2_DEBUGFS_VOOV_RESPONSE:
                rc = i2c_smbus_read_byte_data(psu->client, PMBUS_VOUT_OV_FAULT_RESPONSE);
                if (rc < 0)
                        return rc;

                rc = snprintf(data, 3, "%02x", rc);
                break;
        case Q54SJ108A2_DEBUGFS_IOOC_RESPONSE:
                rc = i2c_smbus_read_byte_data(psu->client, PMBUS_IOUT_OC_FAULT_RESPONSE);
                if (rc < 0)
                        return rc;

                rc = snprintf(data, 3, "%02x", rc);
                break;
        case Q54SJ108A2_DEBUGFS_PMBUS_VERSION:
                rc = i2c_smbus_read_byte_data(psu->client, PMBUS_REVISION);
                if (rc < 0)
                        return rc;

                rc = snprintf(data, 3, "%02x", rc);
                break;
        case Q54SJ108A2_DEBUGFS_MFR_ID:
                rc = i2c_smbus_read_block_data(psu->client, PMBUS_MFR_ID, data);
                if (rc < 0)
                        return rc;
                break;
        case Q54SJ108A2_DEBUGFS_MFR_MODEL:
                rc = i2c_smbus_read_block_data(psu->client, PMBUS_MFR_MODEL, data);
                if (rc < 0)
                        return rc;
                break;
        case Q54SJ108A2_DEBUGFS_MFR_REVISION:
                rc = i2c_smbus_read_block_data(psu->client, PMBUS_MFR_REVISION, data);
                if (rc < 0)
                        return rc;
                break;
        case Q54SJ108A2_DEBUGFS_MFR_LOCATION:
                rc = i2c_smbus_read_block_data(psu->client, PMBUS_MFR_LOCATION, data);
                if (rc < 0)
                        return rc;
                break;
        case Q54SJ108A2_DEBUGFS_BLACKBOX_READ_OFFSET:
                rc = i2c_smbus_read_byte_data(psu->client, READ_HISTORY_EVENT_NUMBER);
                if (rc < 0)
                        return rc;

                rc = snprintf(data, 3, "%02x", rc);
                break;
        case Q54SJ108A2_DEBUGFS_BLACKBOX_READ:
                rc = i2c_smbus_read_block_data(psu->client, READ_HISTORY_EVENTS, data);
                if (rc < 0)
                        return rc;

                res = bin2hex(data_char, data, rc);
                rc = res - data_char;
                out = data_char;
                break;
        case Q54SJ108A2_DEBUGFS_FLASH_KEY:
                rc = i2c_smbus_read_block_data(psu->client, PMBUS_FLASH_KEY_WRITE, data);
                if (rc < 0)
                        return rc;

                res = bin2hex(data_char, data, rc);
                rc = res - data_char;
                out = data_char;
                break;
        default:
                return -EINVAL;
        }

        out[rc] = '\n';
        rc += 2;

        return simple_read_from_buffer(buf, count, ppos, out, rc);
}

static ssize_t q54sj108a2_debugfs_write(struct file *file, const char __user *buf,
                                        size_t count, loff_t *ppos)
{
        u8 flash_key[4];
        u8 dst_data;
        ssize_t rc;
        int *idxp = file->private_data;
        int idx = *idxp;
        struct q54sj108a2_data *psu = to_psu(idxp, idx);

        rc = i2c_smbus_write_byte_data(psu->client, PMBUS_WRITE_PROTECT, 0);
        if (rc)
                return rc;

        switch (idx) {
        case Q54SJ108A2_DEBUGFS_OPERATION:
                rc = kstrtou8_from_user(buf, count, 0, &dst_data);
                if (rc < 0)
                        return rc;

                rc = i2c_smbus_write_byte_data(psu->client, PMBUS_OPERATION, dst_data);
                if (rc < 0)
                        return rc;

                break;
        case Q54SJ108A2_DEBUGFS_CLEARFAULT:
                rc = i2c_smbus_write_byte(psu->client, PMBUS_CLEAR_FAULTS);
                if (rc < 0)
                        return rc;

                break;
        case Q54SJ108A2_DEBUGFS_STOREDEFAULT:
                flash_key[0] = 0x7E;
                flash_key[1] = 0x15;
                flash_key[2] = 0xDC;
                flash_key[3] = 0x42;
                rc = i2c_smbus_write_block_data(psu->client, PMBUS_FLASH_KEY_WRITE, 4, flash_key);
                if (rc < 0)
                        return rc;

                rc = i2c_smbus_write_byte(psu->client, STORE_DEFAULT_ALL);
                if (rc < 0)
                        return rc;

                break;
        case Q54SJ108A2_DEBUGFS_VOOV_RESPONSE:
                rc = kstrtou8_from_user(buf, count, 0, &dst_data);
                if (rc < 0)
                        return rc;

                rc = i2c_smbus_write_byte_data(psu->client, PMBUS_VOUT_OV_FAULT_RESPONSE, dst_data);
                if (rc < 0)
                        return rc;

                break;
        case Q54SJ108A2_DEBUGFS_IOOC_RESPONSE:
                rc = kstrtou8_from_user(buf, count, 0, &dst_data);
                if (rc < 0)
                        return rc;

                rc = i2c_smbus_write_byte_data(psu->client, PMBUS_IOUT_OC_FAULT_RESPONSE, dst_data);
                if (rc < 0)
                        return rc;

                break;
        case Q54SJ108A2_DEBUGFS_BLACKBOX_ERASE:
                rc = i2c_smbus_write_byte(psu->client, ERASE_BLACKBOX_DATA);
                if (rc < 0)
                        return rc;

                break;
        case Q54SJ108A2_DEBUGFS_BLACKBOX_SET_OFFSET:
                rc = kstrtou8_from_user(buf, count, 0, &dst_data);
                if (rc < 0)
                        return rc;

                rc = i2c_smbus_write_byte_data(psu->client, SET_HISTORY_EVENT_OFFSET, dst_data);
                if (rc < 0)
                        return rc;

                break;
        default:
                return -EINVAL;
        }

        return count;
}

static const struct file_operations q54sj108a2_fops = {
        .llseek = noop_llseek,
        .read = q54sj108a2_debugfs_read,
        .write = q54sj108a2_debugfs_write,
        .open = simple_open,
};

static const struct i2c_device_id q54sj108a2_id[] = {
        { "q54sj108a2", q54sj108a2 },
        { },
};

MODULE_DEVICE_TABLE(i2c, q54sj108a2_id);

static int q54sj108a2_probe(struct i2c_client *client)
{
        struct device *dev = &client->dev;
        u8 buf[I2C_SMBUS_BLOCK_MAX + 1];
        enum chips chip_id;
        int ret, i;
        struct dentry *debugfs;
        struct dentry *q54sj108a2_dir;
        struct q54sj108a2_data *psu;

        if (!i2c_check_functionality(client->adapter,
                                     I2C_FUNC_SMBUS_BYTE_DATA |
                                     I2C_FUNC_SMBUS_WORD_DATA |
                                     I2C_FUNC_SMBUS_BLOCK_DATA))
                return -ENODEV;

        if (client->dev.of_node)
                chip_id = (enum chips)(unsigned long)of_device_get_match_data(dev);
        else
                chip_id = i2c_match_id(q54sj108a2_id, client)->driver_data;

        ret = i2c_smbus_read_block_data(client, PMBUS_MFR_ID, buf);
        if (ret < 0) {
                dev_err(&client->dev, "Failed to read Manufacturer ID\n");
                return ret;
        }
        if (ret != 6 || strncmp(buf, "DELTA", 5)) {
                buf[ret] = '\0';
                dev_err(dev, "Unsupported Manufacturer ID '%s'\n", buf);
                return -ENODEV;
        }

        /*
         * The chips support reading PMBUS_MFR_MODEL.
         */
        ret = i2c_smbus_read_block_data(client, PMBUS_MFR_MODEL, buf);
        if (ret < 0) {
                dev_err(dev, "Failed to read Manufacturer Model\n");
                return ret;
        }
        if (ret != 14 || strncmp(buf, "Q54SJ108A2", 10)) {
                buf[ret] = '\0';
                dev_err(dev, "Unsupported Manufacturer Model '%s'\n", buf);
                return -ENODEV;
        }

        ret = i2c_smbus_read_block_data(client, PMBUS_MFR_REVISION, buf);
        if (ret < 0) {
                dev_err(dev, "Failed to read Manufacturer Revision\n");
                return ret;
        }
        if (ret != 4 || buf[0] != 'S') {
                buf[ret] = '\0';
                dev_err(dev, "Unsupported Manufacturer Revision '%s'\n", buf);
                return -ENODEV;
        }

        ret = pmbus_do_probe(client, &q54sj108a2_info[chip_id]);
        if (ret)
                return ret;

        psu = devm_kzalloc(&client->dev, sizeof(*psu), GFP_KERNEL);
        if (!psu)
                return 0;

        psu->client = client;

        debugfs = pmbus_get_debugfs_dir(client);

        q54sj108a2_dir = debugfs_create_dir(client->name, debugfs);

        for (i = 0; i < Q54SJ108A2_DEBUGFS_NUM_ENTRIES; ++i)
                psu->debugfs_entries[i] = i;

        debugfs_create_file("operation", 0644, q54sj108a2_dir,
                            &psu->debugfs_entries[Q54SJ108A2_DEBUGFS_OPERATION],
                            &q54sj108a2_fops);
        debugfs_create_file("clear_fault", 0200, q54sj108a2_dir,
                            &psu->debugfs_entries[Q54SJ108A2_DEBUGFS_CLEARFAULT],
                            &q54sj108a2_fops);
        debugfs_create_file("write_protect", 0444, q54sj108a2_dir,
                            &psu->debugfs_entries[Q54SJ108A2_DEBUGFS_WRITEPROTECT],
                            &q54sj108a2_fops);
        debugfs_create_file("store_default", 0200, q54sj108a2_dir,
                            &psu->debugfs_entries[Q54SJ108A2_DEBUGFS_STOREDEFAULT],
                            &q54sj108a2_fops);
        debugfs_create_file("vo_ov_response", 0644, q54sj108a2_dir,
                            &psu->debugfs_entries[Q54SJ108A2_DEBUGFS_VOOV_RESPONSE],
                            &q54sj108a2_fops);
        debugfs_create_file("io_oc_response", 0644, q54sj108a2_dir,
                            &psu->debugfs_entries[Q54SJ108A2_DEBUGFS_IOOC_RESPONSE],
                            &q54sj108a2_fops);
        debugfs_create_file("pmbus_revision", 0444, q54sj108a2_dir,
                            &psu->debugfs_entries[Q54SJ108A2_DEBUGFS_PMBUS_VERSION],
                            &q54sj108a2_fops);
        debugfs_create_file("mfr_id", 0444, q54sj108a2_dir,
                            &psu->debugfs_entries[Q54SJ108A2_DEBUGFS_MFR_ID],
                            &q54sj108a2_fops);
        debugfs_create_file("mfr_model", 0444, q54sj108a2_dir,
                            &psu->debugfs_entries[Q54SJ108A2_DEBUGFS_MFR_MODEL],
                            &q54sj108a2_fops);
        debugfs_create_file("mfr_revision", 0444, q54sj108a2_dir,
                            &psu->debugfs_entries[Q54SJ108A2_DEBUGFS_MFR_REVISION],
                            &q54sj108a2_fops);
        debugfs_create_file("mfr_location", 0444, q54sj108a2_dir,
                            &psu->debugfs_entries[Q54SJ108A2_DEBUGFS_MFR_LOCATION],
                            &q54sj108a2_fops);
        debugfs_create_file("blackbox_erase", 0200, q54sj108a2_dir,
                            &psu->debugfs_entries[Q54SJ108A2_DEBUGFS_BLACKBOX_ERASE],
                            &q54sj108a2_fops);
        debugfs_create_file("blackbox_read_offset", 0444, q54sj108a2_dir,
                            &psu->debugfs_entries[Q54SJ108A2_DEBUGFS_BLACKBOX_READ_OFFSET],
                            &q54sj108a2_fops);
        debugfs_create_file("blackbox_set_offset", 0200, q54sj108a2_dir,
                            &psu->debugfs_entries[Q54SJ108A2_DEBUGFS_BLACKBOX_SET_OFFSET],
                            &q54sj108a2_fops);
        debugfs_create_file("blackbox_read", 0444, q54sj108a2_dir,
                            &psu->debugfs_entries[Q54SJ108A2_DEBUGFS_BLACKBOX_READ],
                            &q54sj108a2_fops);
        debugfs_create_file("flash_key", 0444, q54sj108a2_dir,
                            &psu->debugfs_entries[Q54SJ108A2_DEBUGFS_FLASH_KEY],
                            &q54sj108a2_fops);

        return 0;
}

static const struct of_device_id q54sj108a2_of_match[] = {
        { .compatible = "delta,q54sj108a2", .data = (void *)q54sj108a2 },
        { },
};

MODULE_DEVICE_TABLE(of, q54sj108a2_of_match);

static struct i2c_driver q54sj108a2_driver = {
        .driver = {
                .name = "q54sj108a2",
                .of_match_table = q54sj108a2_of_match,
        },
        .probe = q54sj108a2_probe,
        .id_table = q54sj108a2_id,
};

module_i2c_driver(q54sj108a2_driver);

MODULE_AUTHOR("Xiao.Ma <xiao.mx.ma@deltaww.com>");
MODULE_DESCRIPTION("PMBus driver for Delta Q54SJ108A2 series modules");
MODULE_LICENSE("GPL");
MODULE_IMPORT_NS("PMBUS");