xref: /openbmc/linux/drivers/hwmon/pmbus/max8688.c (revision 5a158981)
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 
31 static int max8688_read_word_data(struct i2c_client *client, int page, int reg)
32 {
33 	int ret;
34 
35 	if (page > 0)
36 		return -ENXIO;
37 
38 	switch (reg) {
39 	case PMBUS_VIRT_READ_VOUT_MAX:
40 		ret = pmbus_read_word_data(client, 0, MAX8688_MFR_VOUT_PEAK);
41 		break;
42 	case PMBUS_VIRT_READ_IOUT_MAX:
43 		ret = pmbus_read_word_data(client, 0, MAX8688_MFR_IOUT_PEAK);
44 		break;
45 	case PMBUS_VIRT_READ_TEMP_MAX:
46 		ret = pmbus_read_word_data(client, 0,
47 					   MAX8688_MFR_TEMPERATURE_PEAK);
48 		break;
49 	case PMBUS_VIRT_RESET_VOUT_HISTORY:
50 	case PMBUS_VIRT_RESET_IOUT_HISTORY:
51 	case PMBUS_VIRT_RESET_TEMP_HISTORY:
52 		ret = 0;
53 		break;
54 	default:
55 		ret = -ENODATA;
56 		break;
57 	}
58 	return ret;
59 }
60 
61 static int max8688_write_word_data(struct i2c_client *client, int page, int reg,
62 				   u16 word)
63 {
64 	int ret;
65 
66 	switch (reg) {
67 	case PMBUS_VIRT_RESET_VOUT_HISTORY:
68 		ret = pmbus_write_word_data(client, 0, MAX8688_MFR_VOUT_PEAK,
69 					    0);
70 		break;
71 	case PMBUS_VIRT_RESET_IOUT_HISTORY:
72 		ret = pmbus_write_word_data(client, 0, MAX8688_MFR_IOUT_PEAK,
73 					    0);
74 		break;
75 	case PMBUS_VIRT_RESET_TEMP_HISTORY:
76 		ret = pmbus_write_word_data(client, 0,
77 					    MAX8688_MFR_TEMPERATURE_PEAK,
78 					    0xffff);
79 		break;
80 	default:
81 		ret = -ENODATA;
82 		break;
83 	}
84 	return ret;
85 }
86 
87 static int max8688_read_byte_data(struct i2c_client *client, int page, int reg)
88 {
89 	int ret = 0;
90 	int mfg_status;
91 
92 	if (page > 0)
93 		return -ENXIO;
94 
95 	switch (reg) {
96 	case PMBUS_STATUS_VOUT:
97 		mfg_status = pmbus_read_word_data(client, 0,
98 						  MAX8688_MFG_STATUS);
99 		if (mfg_status < 0)
100 			return mfg_status;
101 		if (mfg_status & MAX8688_STATUS_UV_WARNING)
102 			ret |= PB_VOLTAGE_UV_WARNING;
103 		if (mfg_status & MAX8688_STATUS_UV_FAULT)
104 			ret |= PB_VOLTAGE_UV_FAULT;
105 		if (mfg_status & MAX8688_STATUS_OV_WARNING)
106 			ret |= PB_VOLTAGE_OV_WARNING;
107 		if (mfg_status & MAX8688_STATUS_OV_FAULT)
108 			ret |= PB_VOLTAGE_OV_FAULT;
109 		break;
110 	case PMBUS_STATUS_IOUT:
111 		mfg_status = pmbus_read_word_data(client, 0,
112 						  MAX8688_MFG_STATUS);
113 		if (mfg_status < 0)
114 			return mfg_status;
115 		if (mfg_status & MAX8688_STATUS_UC_FAULT)
116 			ret |= PB_IOUT_UC_FAULT;
117 		if (mfg_status & MAX8688_STATUS_OC_WARNING)
118 			ret |= PB_IOUT_OC_WARNING;
119 		if (mfg_status & MAX8688_STATUS_OC_FAULT)
120 			ret |= PB_IOUT_OC_FAULT;
121 		break;
122 	case PMBUS_STATUS_TEMPERATURE:
123 		mfg_status = pmbus_read_word_data(client, 0,
124 						  MAX8688_MFG_STATUS);
125 		if (mfg_status < 0)
126 			return mfg_status;
127 		if (mfg_status & MAX8688_STATUS_OT_WARNING)
128 			ret |= PB_TEMP_OT_WARNING;
129 		if (mfg_status & MAX8688_STATUS_OT_FAULT)
130 			ret |= PB_TEMP_OT_FAULT;
131 		break;
132 	default:
133 		ret = -ENODATA;
134 		break;
135 	}
136 	return ret;
137 }
138 
139 static struct pmbus_driver_info max8688_info = {
140 	.pages = 1,
141 	.format[PSC_VOLTAGE_IN] = direct,
142 	.format[PSC_VOLTAGE_OUT] = direct,
143 	.format[PSC_TEMPERATURE] = direct,
144 	.format[PSC_CURRENT_OUT] = direct,
145 	.m[PSC_VOLTAGE_IN] = 19995,
146 	.b[PSC_VOLTAGE_IN] = 0,
147 	.R[PSC_VOLTAGE_IN] = -1,
148 	.m[PSC_VOLTAGE_OUT] = 19995,
149 	.b[PSC_VOLTAGE_OUT] = 0,
150 	.R[PSC_VOLTAGE_OUT] = -1,
151 	.m[PSC_CURRENT_OUT] = 23109,
152 	.b[PSC_CURRENT_OUT] = 0,
153 	.R[PSC_CURRENT_OUT] = -2,
154 	.m[PSC_TEMPERATURE] = -7612,
155 	.b[PSC_TEMPERATURE] = 335,
156 	.R[PSC_TEMPERATURE] = -3,
157 	.func[0] = PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT | PMBUS_HAVE_TEMP
158 		| PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT
159 		| PMBUS_HAVE_STATUS_TEMP,
160 	.read_byte_data = max8688_read_byte_data,
161 	.read_word_data = max8688_read_word_data,
162 	.write_word_data = max8688_write_word_data,
163 };
164 
165 static int max8688_probe(struct i2c_client *client,
166 			 const struct i2c_device_id *id)
167 {
168 	return pmbus_do_probe(client, id, &max8688_info);
169 }
170 
171 static const struct i2c_device_id max8688_id[] = {
172 	{"max8688", 0},
173 	{ }
174 };
175 
176 MODULE_DEVICE_TABLE(i2c, max8688_id);
177 
178 /* This is the driver that will be inserted */
179 static struct i2c_driver max8688_driver = {
180 	.driver = {
181 		   .name = "max8688",
182 		   },
183 	.probe = max8688_probe,
184 	.remove = pmbus_do_remove,
185 	.id_table = max8688_id,
186 };
187 
188 module_i2c_driver(max8688_driver);
189 
190 MODULE_AUTHOR("Guenter Roeck");
191 MODULE_DESCRIPTION("PMBus driver for Maxim MAX8688");
192 MODULE_LICENSE("GPL");
193