1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Hardware monitoring driver for Maxim MAX8688
4 *
5 * Copyright (c) 2011 Ericsson AB.
6 */
7
8#include <linux/bitops.h>
9#include <linux/kernel.h>
10#include <linux/module.h>
11#include <linux/init.h>
12#include <linux/err.h>
13#include <linux/i2c.h>
14#include "pmbus.h"
15
16#define MAX8688_MFR_VOUT_PEAK		0xd4
17#define MAX8688_MFR_IOUT_PEAK		0xd5
18#define MAX8688_MFR_TEMPERATURE_PEAK	0xd6
19#define MAX8688_MFG_STATUS		0xd8
20
21#define MAX8688_STATUS_OC_FAULT		BIT(4)
22#define MAX8688_STATUS_OV_FAULT		BIT(5)
23#define MAX8688_STATUS_OV_WARNING	BIT(8)
24#define MAX8688_STATUS_UV_FAULT		BIT(9)
25#define MAX8688_STATUS_UV_WARNING	BIT(10)
26#define MAX8688_STATUS_UC_FAULT		BIT(11)
27#define MAX8688_STATUS_OC_WARNING	BIT(12)
28#define MAX8688_STATUS_OT_FAULT		BIT(13)
29#define MAX8688_STATUS_OT_WARNING	BIT(14)
30
31static int max8688_read_word_data(struct i2c_client *client, int page,
32				  int phase, int reg)
33{
34	int ret;
35
36	if (page > 0)
37		return -ENXIO;
38
39	switch (reg) {
40	case PMBUS_VIRT_READ_VOUT_MAX:
41		ret = pmbus_read_word_data(client, 0, 0xff,
42					   MAX8688_MFR_VOUT_PEAK);
43		break;
44	case PMBUS_VIRT_READ_IOUT_MAX:
45		ret = pmbus_read_word_data(client, 0, 0xff,
46					   MAX8688_MFR_IOUT_PEAK);
47		break;
48	case PMBUS_VIRT_READ_TEMP_MAX:
49		ret = pmbus_read_word_data(client, 0, 0xff,
50					   MAX8688_MFR_TEMPERATURE_PEAK);
51		break;
52	case PMBUS_VIRT_RESET_VOUT_HISTORY:
53	case PMBUS_VIRT_RESET_IOUT_HISTORY:
54	case PMBUS_VIRT_RESET_TEMP_HISTORY:
55		ret = 0;
56		break;
57	default:
58		ret = -ENODATA;
59		break;
60	}
61	return ret;
62}
63
64static int max8688_write_word_data(struct i2c_client *client, int page, int reg,
65				   u16 word)
66{
67	int ret;
68
69	switch (reg) {
70	case PMBUS_VIRT_RESET_VOUT_HISTORY:
71		ret = pmbus_write_word_data(client, 0, MAX8688_MFR_VOUT_PEAK,
72					    0);
73		break;
74	case PMBUS_VIRT_RESET_IOUT_HISTORY:
75		ret = pmbus_write_word_data(client, 0, MAX8688_MFR_IOUT_PEAK,
76					    0);
77		break;
78	case PMBUS_VIRT_RESET_TEMP_HISTORY:
79		ret = pmbus_write_word_data(client, 0,
80					    MAX8688_MFR_TEMPERATURE_PEAK,
81					    0xffff);
82		break;
83	default:
84		ret = -ENODATA;
85		break;
86	}
87	return ret;
88}
89
90static int max8688_read_byte_data(struct i2c_client *client, int page, int reg)
91{
92	int ret = 0;
93	int mfg_status;
94
95	if (page > 0)
96		return -ENXIO;
97
98	switch (reg) {
99	case PMBUS_STATUS_VOUT:
100		mfg_status = pmbus_read_word_data(client, 0, 0xff,
101						  MAX8688_MFG_STATUS);
102		if (mfg_status < 0)
103			return mfg_status;
104		if (mfg_status & MAX8688_STATUS_UV_WARNING)
105			ret |= PB_VOLTAGE_UV_WARNING;
106		if (mfg_status & MAX8688_STATUS_UV_FAULT)
107			ret |= PB_VOLTAGE_UV_FAULT;
108		if (mfg_status & MAX8688_STATUS_OV_WARNING)
109			ret |= PB_VOLTAGE_OV_WARNING;
110		if (mfg_status & MAX8688_STATUS_OV_FAULT)
111			ret |= PB_VOLTAGE_OV_FAULT;
112		break;
113	case PMBUS_STATUS_IOUT:
114		mfg_status = pmbus_read_word_data(client, 0, 0xff,
115						  MAX8688_MFG_STATUS);
116		if (mfg_status < 0)
117			return mfg_status;
118		if (mfg_status & MAX8688_STATUS_UC_FAULT)
119			ret |= PB_IOUT_UC_FAULT;
120		if (mfg_status & MAX8688_STATUS_OC_WARNING)
121			ret |= PB_IOUT_OC_WARNING;
122		if (mfg_status & MAX8688_STATUS_OC_FAULT)
123			ret |= PB_IOUT_OC_FAULT;
124		break;
125	case PMBUS_STATUS_TEMPERATURE:
126		mfg_status = pmbus_read_word_data(client, 0, 0xff,
127						  MAX8688_MFG_STATUS);
128		if (mfg_status < 0)
129			return mfg_status;
130		if (mfg_status & MAX8688_STATUS_OT_WARNING)
131			ret |= PB_TEMP_OT_WARNING;
132		if (mfg_status & MAX8688_STATUS_OT_FAULT)
133			ret |= PB_TEMP_OT_FAULT;
134		break;
135	default:
136		ret = -ENODATA;
137		break;
138	}
139	return ret;
140}
141
142static struct pmbus_driver_info max8688_info = {
143	.pages = 1,
144	.format[PSC_VOLTAGE_IN] = direct,
145	.format[PSC_VOLTAGE_OUT] = direct,
146	.format[PSC_TEMPERATURE] = direct,
147	.format[PSC_CURRENT_OUT] = direct,
148	.m[PSC_VOLTAGE_IN] = 19995,
149	.b[PSC_VOLTAGE_IN] = 0,
150	.R[PSC_VOLTAGE_IN] = -1,
151	.m[PSC_VOLTAGE_OUT] = 19995,
152	.b[PSC_VOLTAGE_OUT] = 0,
153	.R[PSC_VOLTAGE_OUT] = -1,
154	.m[PSC_CURRENT_OUT] = 23109,
155	.b[PSC_CURRENT_OUT] = 0,
156	.R[PSC_CURRENT_OUT] = -2,
157	.m[PSC_TEMPERATURE] = -7612,
158	.b[PSC_TEMPERATURE] = 335,
159	.R[PSC_TEMPERATURE] = -3,
160	.func[0] = PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT | PMBUS_HAVE_TEMP
161		| PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT
162		| PMBUS_HAVE_STATUS_TEMP,
163	.read_byte_data = max8688_read_byte_data,
164	.read_word_data = max8688_read_word_data,
165	.write_word_data = max8688_write_word_data,
166};
167
168static int max8688_probe(struct i2c_client *client)
169{
170	return pmbus_do_probe(client, &max8688_info);
171}
172
173static const struct i2c_device_id max8688_id[] = {
174	{"max8688", 0},
175	{ }
176};
177
178MODULE_DEVICE_TABLE(i2c, max8688_id);
179
180/* This is the driver that will be inserted */
181static struct i2c_driver max8688_driver = {
182	.driver = {
183		   .name = "max8688",
184		   },
185	.probe = max8688_probe,
186	.id_table = max8688_id,
187};
188
189module_i2c_driver(max8688_driver);
190
191MODULE_AUTHOR("Guenter Roeck");
192MODULE_DESCRIPTION("PMBus driver for Maxim MAX8688");
193MODULE_LICENSE("GPL");
194MODULE_IMPORT_NS(PMBUS);
195