1 /*
2 * Hardware monitoring driver for PMBus devices
3 *
4 * Copyright (c) 2010, 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/kernel.h>
22 #include <linux/module.h>
23 #include <linux/init.h>
24 #include <linux/err.h>
25 #include <linux/slab.h>
26 #include <linux/mutex.h>
27 #include <linux/i2c.h>
28 #include "pmbus.h"
29
30 /*
31 * Find sensor groups and status registers on each page.
32 */
pmbus_find_sensor_groups(struct i2c_client * client,struct pmbus_driver_info * info)33 static void pmbus_find_sensor_groups(struct i2c_client *client,
34 struct pmbus_driver_info *info)
35 {
36 int page;
37
38 /* Sensors detected on page 0 only */
39 if (pmbus_check_word_register(client, 0, PMBUS_READ_VIN))
40 info->func[0] |= PMBUS_HAVE_VIN;
41 if (pmbus_check_word_register(client, 0, PMBUS_READ_VCAP))
42 info->func[0] |= PMBUS_HAVE_VCAP;
43 if (pmbus_check_word_register(client, 0, PMBUS_READ_IIN))
44 info->func[0] |= PMBUS_HAVE_IIN;
45 if (pmbus_check_word_register(client, 0, PMBUS_READ_PIN))
46 info->func[0] |= PMBUS_HAVE_PIN;
47 if (info->func[0]
48 && pmbus_check_byte_register(client, 0, PMBUS_STATUS_INPUT))
49 info->func[0] |= PMBUS_HAVE_STATUS_INPUT;
50 if (pmbus_check_byte_register(client, 0, PMBUS_FAN_CONFIG_12) &&
51 pmbus_check_word_register(client, 0, PMBUS_READ_FAN_SPEED_1)) {
52 info->func[0] |= PMBUS_HAVE_FAN12;
53 if (pmbus_check_byte_register(client, 0, PMBUS_STATUS_FAN_12))
54 info->func[0] |= PMBUS_HAVE_STATUS_FAN12;
55 }
56 if (pmbus_check_byte_register(client, 0, PMBUS_FAN_CONFIG_34) &&
57 pmbus_check_word_register(client, 0, PMBUS_READ_FAN_SPEED_3)) {
58 info->func[0] |= PMBUS_HAVE_FAN34;
59 if (pmbus_check_byte_register(client, 0, PMBUS_STATUS_FAN_34))
60 info->func[0] |= PMBUS_HAVE_STATUS_FAN34;
61 }
62 if (pmbus_check_word_register(client, 0, PMBUS_READ_TEMPERATURE_1))
63 info->func[0] |= PMBUS_HAVE_TEMP;
64 if (pmbus_check_word_register(client, 0, PMBUS_READ_TEMPERATURE_2))
65 info->func[0] |= PMBUS_HAVE_TEMP2;
66 if (pmbus_check_word_register(client, 0, PMBUS_READ_TEMPERATURE_3))
67 info->func[0] |= PMBUS_HAVE_TEMP3;
68 if (info->func[0] & (PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2
69 | PMBUS_HAVE_TEMP3)
70 && pmbus_check_byte_register(client, 0,
71 PMBUS_STATUS_TEMPERATURE))
72 info->func[0] |= PMBUS_HAVE_STATUS_TEMP;
73
74 /* Sensors detected on all pages */
75 for (page = 0; page < info->pages; page++) {
76 if (pmbus_check_word_register(client, page, PMBUS_READ_VOUT)) {
77 info->func[page] |= PMBUS_HAVE_VOUT;
78 if (pmbus_check_byte_register(client, page,
79 PMBUS_STATUS_VOUT))
80 info->func[page] |= PMBUS_HAVE_STATUS_VOUT;
81 }
82 if (pmbus_check_word_register(client, page, PMBUS_READ_IOUT)) {
83 info->func[page] |= PMBUS_HAVE_IOUT;
84 if (pmbus_check_byte_register(client, 0,
85 PMBUS_STATUS_IOUT))
86 info->func[page] |= PMBUS_HAVE_STATUS_IOUT;
87 }
88 if (pmbus_check_word_register(client, page, PMBUS_READ_POUT))
89 info->func[page] |= PMBUS_HAVE_POUT;
90 }
91 }
92
93 /*
94 * Identify chip parameters.
95 */
pmbus_identify(struct i2c_client * client,struct pmbus_driver_info * info)96 static int pmbus_identify(struct i2c_client *client,
97 struct pmbus_driver_info *info)
98 {
99 int ret = 0;
100
101 if (!info->pages) {
102 /*
103 * Check if the PAGE command is supported. If it is,
104 * keep setting the page number until it fails or until the
105 * maximum number of pages has been reached. Assume that
106 * this is the number of pages supported by the chip.
107 */
108 if (pmbus_check_byte_register(client, 0, PMBUS_PAGE)) {
109 int page;
110
111 for (page = 1; page < PMBUS_PAGES; page++) {
112 if (pmbus_set_page(client, page) < 0)
113 break;
114 }
115 pmbus_set_page(client, 0);
116 info->pages = page;
117 } else {
118 info->pages = 1;
119 }
120
121 pmbus_clear_faults(client);
122 }
123
124 if (pmbus_check_byte_register(client, 0, PMBUS_VOUT_MODE)) {
125 int vout_mode;
126
127 vout_mode = pmbus_read_byte_data(client, 0, PMBUS_VOUT_MODE);
128 if (vout_mode >= 0 && vout_mode != 0xff) {
129 switch (vout_mode >> 5) {
130 case 0:
131 break;
132 case 1:
133 info->format[PSC_VOLTAGE_OUT] = vid;
134 info->vrm_version = vr11;
135 break;
136 case 2:
137 info->format[PSC_VOLTAGE_OUT] = direct;
138 break;
139 default:
140 ret = -ENODEV;
141 goto abort;
142 }
143 }
144 }
145
146 /*
147 * We should check if the COEFFICIENTS register is supported.
148 * If it is, and the chip is configured for direct mode, we can read
149 * the coefficients from the chip, one set per group of sensor
150 * registers.
151 *
152 * To do this, we will need access to a chip which actually supports the
153 * COEFFICIENTS command, since the command is too complex to implement
154 * without testing it. Until then, abort if a chip configured for direct
155 * mode was detected.
156 */
157 if (info->format[PSC_VOLTAGE_OUT] == direct) {
158 ret = -ENODEV;
159 goto abort;
160 }
161
162 /* Try to find sensor groups */
163 pmbus_find_sensor_groups(client, info);
164 abort:
165 return ret;
166 }
167
pmbus_probe(struct i2c_client * client,const struct i2c_device_id * id)168 static int pmbus_probe(struct i2c_client *client,
169 const struct i2c_device_id *id)
170 {
171 struct pmbus_driver_info *info;
172
173 info = devm_kzalloc(&client->dev, sizeof(struct pmbus_driver_info),
174 GFP_KERNEL);
175 if (!info)
176 return -ENOMEM;
177
178 info->pages = id->driver_data;
179 info->identify = pmbus_identify;
180
181 return pmbus_do_probe(client, id, info);
182 }
183
184 /*
185 * Use driver_data to set the number of pages supported by the chip.
186 */
187 static const struct i2c_device_id pmbus_id[] = {
188 {"adp4000", 1},
189 {"bmr453", 1},
190 {"bmr454", 1},
191 {"mdt040", 1},
192 {"ncp4200", 1},
193 {"ncp4208", 1},
194 {"pdt003", 1},
195 {"pdt006", 1},
196 {"pdt012", 1},
197 {"pmbus", 0},
198 {"tps40400", 1},
199 {"tps544b20", 1},
200 {"tps544b25", 1},
201 {"tps544c20", 1},
202 {"tps544c25", 1},
203 {"udt020", 1},
204 {}
205 };
206
207 MODULE_DEVICE_TABLE(i2c, pmbus_id);
208
209 /* This is the driver that will be inserted */
210 static struct i2c_driver pmbus_driver = {
211 .driver = {
212 .name = "pmbus",
213 },
214 .probe = pmbus_probe,
215 .remove = pmbus_do_remove,
216 .id_table = pmbus_id,
217 };
218
219 module_i2c_driver(pmbus_driver);
220
221 MODULE_AUTHOR("Guenter Roeck");
222 MODULE_DESCRIPTION("Generic PMBus driver");
223 MODULE_LICENSE("GPL");
224