xref: /openbmc/linux/drivers/hwmon/pmbus/max8688.c (revision eb3fcf00)
1 /*
2  * Hardware monitoring driver for Maxim MAX8688
3  *
4  * Copyright (c) 2011 Ericsson AB.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19  */
20 
21 #include <linux/bitops.h>
22 #include <linux/kernel.h>
23 #include <linux/module.h>
24 #include <linux/init.h>
25 #include <linux/err.h>
26 #include <linux/i2c.h>
27 #include "pmbus.h"
28 
29 #define MAX8688_MFR_VOUT_PEAK		0xd4
30 #define MAX8688_MFR_IOUT_PEAK		0xd5
31 #define MAX8688_MFR_TEMPERATURE_PEAK	0xd6
32 #define MAX8688_MFG_STATUS		0xd8
33 
34 #define MAX8688_STATUS_OC_FAULT		BIT(4)
35 #define MAX8688_STATUS_OV_FAULT		BIT(5)
36 #define MAX8688_STATUS_OV_WARNING	BIT(8)
37 #define MAX8688_STATUS_UV_FAULT		BIT(9)
38 #define MAX8688_STATUS_UV_WARNING	BIT(10)
39 #define MAX8688_STATUS_UC_FAULT		BIT(11)
40 #define MAX8688_STATUS_OC_WARNING	BIT(12)
41 #define MAX8688_STATUS_OT_FAULT		BIT(13)
42 #define MAX8688_STATUS_OT_WARNING	BIT(14)
43 
44 static int max8688_read_word_data(struct i2c_client *client, int page, int reg)
45 {
46 	int ret;
47 
48 	if (page)
49 		return -ENXIO;
50 
51 	switch (reg) {
52 	case PMBUS_VIRT_READ_VOUT_MAX:
53 		ret = pmbus_read_word_data(client, 0, MAX8688_MFR_VOUT_PEAK);
54 		break;
55 	case PMBUS_VIRT_READ_IOUT_MAX:
56 		ret = pmbus_read_word_data(client, 0, MAX8688_MFR_IOUT_PEAK);
57 		break;
58 	case PMBUS_VIRT_READ_TEMP_MAX:
59 		ret = pmbus_read_word_data(client, 0,
60 					   MAX8688_MFR_TEMPERATURE_PEAK);
61 		break;
62 	case PMBUS_VIRT_RESET_VOUT_HISTORY:
63 	case PMBUS_VIRT_RESET_IOUT_HISTORY:
64 	case PMBUS_VIRT_RESET_TEMP_HISTORY:
65 		ret = 0;
66 		break;
67 	default:
68 		ret = -ENODATA;
69 		break;
70 	}
71 	return ret;
72 }
73 
74 static int max8688_write_word_data(struct i2c_client *client, int page, int reg,
75 				   u16 word)
76 {
77 	int ret;
78 
79 	switch (reg) {
80 	case PMBUS_VIRT_RESET_VOUT_HISTORY:
81 		ret = pmbus_write_word_data(client, 0, MAX8688_MFR_VOUT_PEAK,
82 					    0);
83 		break;
84 	case PMBUS_VIRT_RESET_IOUT_HISTORY:
85 		ret = pmbus_write_word_data(client, 0, MAX8688_MFR_IOUT_PEAK,
86 					    0);
87 		break;
88 	case PMBUS_VIRT_RESET_TEMP_HISTORY:
89 		ret = pmbus_write_word_data(client, 0,
90 					    MAX8688_MFR_TEMPERATURE_PEAK,
91 					    0xffff);
92 		break;
93 	default:
94 		ret = -ENODATA;
95 		break;
96 	}
97 	return ret;
98 }
99 
100 static int max8688_read_byte_data(struct i2c_client *client, int page, int reg)
101 {
102 	int ret = 0;
103 	int mfg_status;
104 
105 	if (page > 0)
106 		return -ENXIO;
107 
108 	switch (reg) {
109 	case PMBUS_STATUS_VOUT:
110 		mfg_status = pmbus_read_word_data(client, 0,
111 						  MAX8688_MFG_STATUS);
112 		if (mfg_status < 0)
113 			return mfg_status;
114 		if (mfg_status & MAX8688_STATUS_UV_WARNING)
115 			ret |= PB_VOLTAGE_UV_WARNING;
116 		if (mfg_status & MAX8688_STATUS_UV_FAULT)
117 			ret |= PB_VOLTAGE_UV_FAULT;
118 		if (mfg_status & MAX8688_STATUS_OV_WARNING)
119 			ret |= PB_VOLTAGE_OV_WARNING;
120 		if (mfg_status & MAX8688_STATUS_OV_FAULT)
121 			ret |= PB_VOLTAGE_OV_FAULT;
122 		break;
123 	case PMBUS_STATUS_IOUT:
124 		mfg_status = pmbus_read_word_data(client, 0,
125 						  MAX8688_MFG_STATUS);
126 		if (mfg_status < 0)
127 			return mfg_status;
128 		if (mfg_status & MAX8688_STATUS_UC_FAULT)
129 			ret |= PB_IOUT_UC_FAULT;
130 		if (mfg_status & MAX8688_STATUS_OC_WARNING)
131 			ret |= PB_IOUT_OC_WARNING;
132 		if (mfg_status & MAX8688_STATUS_OC_FAULT)
133 			ret |= PB_IOUT_OC_FAULT;
134 		break;
135 	case PMBUS_STATUS_TEMPERATURE:
136 		mfg_status = pmbus_read_word_data(client, 0,
137 						  MAX8688_MFG_STATUS);
138 		if (mfg_status < 0)
139 			return mfg_status;
140 		if (mfg_status & MAX8688_STATUS_OT_WARNING)
141 			ret |= PB_TEMP_OT_WARNING;
142 		if (mfg_status & MAX8688_STATUS_OT_FAULT)
143 			ret |= PB_TEMP_OT_FAULT;
144 		break;
145 	default:
146 		ret = -ENODATA;
147 		break;
148 	}
149 	return ret;
150 }
151 
152 static struct pmbus_driver_info max8688_info = {
153 	.pages = 1,
154 	.format[PSC_VOLTAGE_IN] = direct,
155 	.format[PSC_VOLTAGE_OUT] = direct,
156 	.format[PSC_TEMPERATURE] = direct,
157 	.format[PSC_CURRENT_OUT] = direct,
158 	.m[PSC_VOLTAGE_IN] = 19995,
159 	.b[PSC_VOLTAGE_IN] = 0,
160 	.R[PSC_VOLTAGE_IN] = -1,
161 	.m[PSC_VOLTAGE_OUT] = 19995,
162 	.b[PSC_VOLTAGE_OUT] = 0,
163 	.R[PSC_VOLTAGE_OUT] = -1,
164 	.m[PSC_CURRENT_OUT] = 23109,
165 	.b[PSC_CURRENT_OUT] = 0,
166 	.R[PSC_CURRENT_OUT] = -2,
167 	.m[PSC_TEMPERATURE] = -7612,
168 	.b[PSC_TEMPERATURE] = 335,
169 	.R[PSC_TEMPERATURE] = -3,
170 	.func[0] = PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT | PMBUS_HAVE_TEMP
171 		| PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT
172 		| PMBUS_HAVE_STATUS_TEMP,
173 	.read_byte_data = max8688_read_byte_data,
174 	.read_word_data = max8688_read_word_data,
175 	.write_word_data = max8688_write_word_data,
176 };
177 
178 static int max8688_probe(struct i2c_client *client,
179 			 const struct i2c_device_id *id)
180 {
181 	return pmbus_do_probe(client, id, &max8688_info);
182 }
183 
184 static const struct i2c_device_id max8688_id[] = {
185 	{"max8688", 0},
186 	{ }
187 };
188 
189 MODULE_DEVICE_TABLE(i2c, max8688_id);
190 
191 /* This is the driver that will be inserted */
192 static struct i2c_driver max8688_driver = {
193 	.driver = {
194 		   .name = "max8688",
195 		   },
196 	.probe = max8688_probe,
197 	.remove = pmbus_do_remove,
198 	.id_table = max8688_id,
199 };
200 
201 module_i2c_driver(max8688_driver);
202 
203 MODULE_AUTHOR("Guenter Roeck");
204 MODULE_DESCRIPTION("PMBus driver for Maxim MAX8688");
205 MODULE_LICENSE("GPL");
206