drivers/hwmon/pmbus/q54sj108a2.c - linux - Git at Google

 // 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/i2c.h>
 #include <linux/module.h>
 #include <linux/of_device.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] = { 0 };
 	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, data_char, 32);
 		rc = res - data;

 		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, data_char, 4);
 		rc = res - data;

 		break;
 	default:
 		return -EINVAL;
 	}

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

 	return simple_read_from_buffer(buf, count, ppos, data, 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 != 5 || 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_new = 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");
	// 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/i2c.h>
	#include <linux/module.h>
	#include <linux/of_device.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] = { 0 };
	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, data_char, 32);
	rc = res - data;

	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, data_char, 4);
	rc = res - data;

	break;
	default:
	return -EINVAL;
	}

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

	return simple_read_from_buffer(buf, count, ppos, data, 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 != 5 \|\| 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_new = 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");