1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * Hardware monitoring driver for IR35221
  4 *
  5 * Copyright (C) IBM Corporation 2017.
  6 */
  7
  8#include <linux/err.h>
  9#include <linux/i2c.h>
 10#include <linux/init.h>
 11#include <linux/kernel.h>
 12#include <linux/module.h>
 13#include "pmbus.h"
 14
 15#define IR35221_MFR_VIN_PEAK		0xc5
 16#define IR35221_MFR_VOUT_PEAK		0xc6
 17#define IR35221_MFR_IOUT_PEAK		0xc7
 18#define IR35221_MFR_TEMP_PEAK		0xc8
 19#define IR35221_MFR_VIN_VALLEY		0xc9
 20#define IR35221_MFR_VOUT_VALLEY		0xca
 21#define IR35221_MFR_IOUT_VALLEY		0xcb
 22#define IR35221_MFR_TEMP_VALLEY		0xcc
 23
 24static int ir35221_read_word_data(struct i2c_client *client, int page,
 25				  int phase, int reg)
 26{
 27	int ret;
 28
 29	switch (reg) {
 30	case PMBUS_VIRT_READ_VIN_MAX:
 31		ret = pmbus_read_word_data(client, page, phase,
 32					   IR35221_MFR_VIN_PEAK);
 33		break;
 34	case PMBUS_VIRT_READ_VOUT_MAX:
 35		ret = pmbus_read_word_data(client, page, phase,
 36					   IR35221_MFR_VOUT_PEAK);
 37		break;
 38	case PMBUS_VIRT_READ_IOUT_MAX:
 39		ret = pmbus_read_word_data(client, page, phase,
 40					   IR35221_MFR_IOUT_PEAK);
 41		break;
 42	case PMBUS_VIRT_READ_TEMP_MAX:
 43		ret = pmbus_read_word_data(client, page, phase,
 44					   IR35221_MFR_TEMP_PEAK);
 45		break;
 46	case PMBUS_VIRT_READ_VIN_MIN:
 47		ret = pmbus_read_word_data(client, page, phase,
 48					   IR35221_MFR_VIN_VALLEY);
 49		break;
 50	case PMBUS_VIRT_READ_VOUT_MIN:
 51		ret = pmbus_read_word_data(client, page, phase,
 52					   IR35221_MFR_VOUT_VALLEY);
 53		break;
 54	case PMBUS_VIRT_READ_IOUT_MIN:
 55		ret = pmbus_read_word_data(client, page, phase,
 56					   IR35221_MFR_IOUT_VALLEY);
 57		break;
 58	case PMBUS_VIRT_READ_TEMP_MIN:
 59		ret = pmbus_read_word_data(client, page, phase,
 60					   IR35221_MFR_TEMP_VALLEY);
 61		break;
 62	default:
 63		ret = -ENODATA;
 64		break;
 65	}
 66
 67	return ret;
 68}
 69
 70static int ir35221_probe(struct i2c_client *client)
 71{
 72	struct pmbus_driver_info *info;
 73	u8 buf[I2C_SMBUS_BLOCK_MAX];
 74	int ret;
 75
 76	if (!i2c_check_functionality(client->adapter,
 77				     I2C_FUNC_SMBUS_READ_BYTE_DATA
 78				| I2C_FUNC_SMBUS_READ_WORD_DATA
 79				| I2C_FUNC_SMBUS_READ_BLOCK_DATA))
 80		return -ENODEV;
 81
 82	ret = i2c_smbus_read_block_data(client, PMBUS_MFR_ID, buf);
 83	if (ret < 0) {
 84		dev_err(&client->dev, "Failed to read PMBUS_MFR_ID\n");
 85		return ret;
 86	}
 87	if (ret != 2 || strncmp(buf, "RI", strlen("RI"))) {
 88		dev_err(&client->dev, "MFR_ID unrecognised\n");
 89		return -ENODEV;
 90	}
 91
 92	ret = i2c_smbus_read_block_data(client, PMBUS_MFR_MODEL, buf);
 93	if (ret < 0) {
 94		dev_err(&client->dev, "Failed to read PMBUS_MFR_MODEL\n");
 95		return ret;
 96	}
 97	if (ret != 2 || !(buf[0] == 0x6c && buf[1] == 0x00)) {
 98		dev_err(&client->dev, "MFR_MODEL unrecognised\n");
 99		return -ENODEV;
100	}
101
102	info = devm_kzalloc(&client->dev, sizeof(struct pmbus_driver_info),
103			    GFP_KERNEL);
104	if (!info)
105		return -ENOMEM;
106
107	info->read_word_data = ir35221_read_word_data;
108
109	info->pages = 2;
110	info->format[PSC_VOLTAGE_IN] = linear;
111	info->format[PSC_VOLTAGE_OUT] = linear;
112	info->format[PSC_CURRENT_IN] = linear;
113	info->format[PSC_CURRENT_OUT] = linear;
114	info->format[PSC_POWER] = linear;
115	info->format[PSC_TEMPERATURE] = linear;
116
117	info->func[0] = PMBUS_HAVE_VIN
118		| PMBUS_HAVE_VOUT | PMBUS_HAVE_IIN
119		| PMBUS_HAVE_IOUT | PMBUS_HAVE_PIN
120		| PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP
121		| PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT
122		| PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP;
123	info->func[1] = info->func[0];
124
125	return pmbus_do_probe(client, info);
126}
127
128static const struct i2c_device_id ir35221_id[] = {
129	{"ir35221", 0},
130	{}
131};
132
133MODULE_DEVICE_TABLE(i2c, ir35221_id);
134
135static struct i2c_driver ir35221_driver = {
136	.driver = {
137		.name	= "ir35221",
138	},
139	.probe_new	= ir35221_probe,
140	.id_table	= ir35221_id,
141};
142
143module_i2c_driver(ir35221_driver);
144
145MODULE_AUTHOR("Samuel Mendoza-Jonas <sam@mendozajonas.com");
146MODULE_DESCRIPTION("PMBus driver for IR35221");
147MODULE_LICENSE("GPL");
148MODULE_IMPORT_NS(PMBUS);