1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Hardware monitoring driver for PMBus devices
4 *
5 * Copyright (c) 2010, 2011 Ericsson AB.
6 */
7
8 #include <linux/kernel.h>
9 #include <linux/module.h>
10 #include <linux/init.h>
11 #include <linux/err.h>
12 #include <linux/slab.h>
13 #include <linux/mutex.h>
14 #include <linux/i2c.h>
15 #include <linux/pmbus.h>
16 #include "pmbus.h"
17
18 struct pmbus_device_info {
19 int pages;
20 u32 flags;
21 };
22
23 static const struct i2c_device_id pmbus_id[];
24
25 /*
26 * Find sensor groups and status registers on each page.
27 */
pmbus_find_sensor_groups(struct i2c_client * client,struct pmbus_driver_info * info)28 static void pmbus_find_sensor_groups(struct i2c_client *client,
29 struct pmbus_driver_info *info)
30 {
31 int page;
32
33 /* Sensors detected on page 0 only */
34 if (pmbus_check_word_register(client, 0, PMBUS_READ_VIN))
35 info->func[0] |= PMBUS_HAVE_VIN;
36 if (pmbus_check_word_register(client, 0, PMBUS_READ_VCAP))
37 info->func[0] |= PMBUS_HAVE_VCAP;
38 if (pmbus_check_word_register(client, 0, PMBUS_READ_IIN))
39 info->func[0] |= PMBUS_HAVE_IIN;
40 if (pmbus_check_word_register(client, 0, PMBUS_READ_PIN))
41 info->func[0] |= PMBUS_HAVE_PIN;
42 if (info->func[0]
43 && pmbus_check_byte_register(client, 0, PMBUS_STATUS_INPUT))
44 info->func[0] |= PMBUS_HAVE_STATUS_INPUT;
45 if (pmbus_check_byte_register(client, 0, PMBUS_FAN_CONFIG_12) &&
46 pmbus_check_word_register(client, 0, PMBUS_READ_FAN_SPEED_1)) {
47 info->func[0] |= PMBUS_HAVE_FAN12;
48 if (pmbus_check_byte_register(client, 0, PMBUS_STATUS_FAN_12))
49 info->func[0] |= PMBUS_HAVE_STATUS_FAN12;
50 }
51 if (pmbus_check_byte_register(client, 0, PMBUS_FAN_CONFIG_34) &&
52 pmbus_check_word_register(client, 0, PMBUS_READ_FAN_SPEED_3)) {
53 info->func[0] |= PMBUS_HAVE_FAN34;
54 if (pmbus_check_byte_register(client, 0, PMBUS_STATUS_FAN_34))
55 info->func[0] |= PMBUS_HAVE_STATUS_FAN34;
56 }
57 if (pmbus_check_word_register(client, 0, PMBUS_READ_TEMPERATURE_1))
58 info->func[0] |= PMBUS_HAVE_TEMP;
59 if (pmbus_check_word_register(client, 0, PMBUS_READ_TEMPERATURE_2))
60 info->func[0] |= PMBUS_HAVE_TEMP2;
61 if (pmbus_check_word_register(client, 0, PMBUS_READ_TEMPERATURE_3))
62 info->func[0] |= PMBUS_HAVE_TEMP3;
63 if (info->func[0] & (PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2
64 | PMBUS_HAVE_TEMP3)
65 && pmbus_check_byte_register(client, 0,
66 PMBUS_STATUS_TEMPERATURE))
67 info->func[0] |= PMBUS_HAVE_STATUS_TEMP;
68
69 /* Sensors detected on all pages */
70 for (page = 0; page < info->pages; page++) {
71 if (pmbus_check_word_register(client, page, PMBUS_READ_VOUT)) {
72 info->func[page] |= PMBUS_HAVE_VOUT;
73 if (pmbus_check_byte_register(client, page,
74 PMBUS_STATUS_VOUT))
75 info->func[page] |= PMBUS_HAVE_STATUS_VOUT;
76 }
77 if (pmbus_check_word_register(client, page, PMBUS_READ_IOUT)) {
78 info->func[page] |= PMBUS_HAVE_IOUT;
79 if (pmbus_check_byte_register(client, 0,
80 PMBUS_STATUS_IOUT))
81 info->func[page] |= PMBUS_HAVE_STATUS_IOUT;
82 }
83 if (pmbus_check_word_register(client, page, PMBUS_READ_POUT))
84 info->func[page] |= PMBUS_HAVE_POUT;
85 }
86 }
87
88 /*
89 * Identify chip parameters.
90 */
pmbus_identify(struct i2c_client * client,struct pmbus_driver_info * info)91 static int pmbus_identify(struct i2c_client *client,
92 struct pmbus_driver_info *info)
93 {
94 int ret = 0;
95
96 if (!info->pages) {
97 /*
98 * Check if the PAGE command is supported. If it is,
99 * keep setting the page number until it fails or until the
100 * maximum number of pages has been reached. Assume that
101 * this is the number of pages supported by the chip.
102 */
103 if (pmbus_check_byte_register(client, 0, PMBUS_PAGE)) {
104 int page;
105
106 info->pages = PMBUS_PAGES;
107
108 for (page = 1; page < PMBUS_PAGES; page++) {
109 if (pmbus_set_page(client, page, 0xff) < 0)
110 break;
111 }
112 pmbus_set_page(client, 0, 0xff);
113 info->pages = page;
114 } else {
115 info->pages = 1;
116 }
117
118 pmbus_clear_faults(client);
119 }
120
121 if (pmbus_check_byte_register(client, 0, PMBUS_VOUT_MODE)) {
122 int vout_mode, i;
123
124 vout_mode = pmbus_read_byte_data(client, 0, PMBUS_VOUT_MODE);
125 if (vout_mode >= 0 && vout_mode != 0xff) {
126 switch (vout_mode >> 5) {
127 case 0:
128 break;
129 case 1:
130 info->format[PSC_VOLTAGE_OUT] = vid;
131 for (i = 0; i < info->pages; i++)
132 info->vrm_version[i] = vr11;
133 break;
134 case 2:
135 info->format[PSC_VOLTAGE_OUT] = direct;
136 break;
137 default:
138 ret = -ENODEV;
139 goto abort;
140 }
141 }
142 }
143
144 /*
145 * We should check if the COEFFICIENTS register is supported.
146 * If it is, and the chip is configured for direct mode, we can read
147 * the coefficients from the chip, one set per group of sensor
148 * registers.
149 *
150 * To do this, we will need access to a chip which actually supports the
151 * COEFFICIENTS command, since the command is too complex to implement
152 * without testing it. Until then, abort if a chip configured for direct
153 * mode was detected.
154 */
155 if (info->format[PSC_VOLTAGE_OUT] == direct) {
156 ret = -ENODEV;
157 goto abort;
158 }
159
160 /* Try to find sensor groups */
161 pmbus_find_sensor_groups(client, info);
162 abort:
163 return ret;
164 }
165
pmbus_probe(struct i2c_client * client)166 static int pmbus_probe(struct i2c_client *client)
167 {
168 struct pmbus_driver_info *info;
169 struct pmbus_platform_data *pdata = NULL;
170 struct device *dev = &client->dev;
171 struct pmbus_device_info *device_info;
172
173 info = devm_kzalloc(dev, sizeof(struct pmbus_driver_info), GFP_KERNEL);
174 if (!info)
175 return -ENOMEM;
176
177 device_info = (struct pmbus_device_info *)i2c_match_id(pmbus_id, client)->driver_data;
178 if (device_info->flags) {
179 pdata = devm_kzalloc(dev, sizeof(struct pmbus_platform_data),
180 GFP_KERNEL);
181 if (!pdata)
182 return -ENOMEM;
183
184 pdata->flags = device_info->flags;
185 }
186
187 info->pages = device_info->pages;
188 info->identify = pmbus_identify;
189 dev->platform_data = pdata;
190
191 return pmbus_do_probe(client, info);
192 }
193
194 static const struct pmbus_device_info pmbus_info_one = {
195 .pages = 1,
196 .flags = 0
197 };
198
199 static const struct pmbus_device_info pmbus_info_zero = {
200 .pages = 0,
201 .flags = 0
202 };
203
204 static const struct pmbus_device_info pmbus_info_one_skip = {
205 .pages = 1,
206 .flags = PMBUS_SKIP_STATUS_CHECK
207 };
208
209 static const struct pmbus_device_info pmbus_info_one_status = {
210 .pages = 1,
211 .flags = PMBUS_READ_STATUS_AFTER_FAILED_CHECK
212 };
213
214 /*
215 * Use driver_data to set the number of pages supported by the chip.
216 */
217 static const struct i2c_device_id pmbus_id[] = {
218 {"adp4000", (kernel_ulong_t)&pmbus_info_one},
219 {"bmr310", (kernel_ulong_t)&pmbus_info_one_status},
220 {"bmr453", (kernel_ulong_t)&pmbus_info_one},
221 {"bmr454", (kernel_ulong_t)&pmbus_info_one},
222 {"bmr456", (kernel_ulong_t)&pmbus_info_one},
223 {"bmr457", (kernel_ulong_t)&pmbus_info_one},
224 {"bmr458", (kernel_ulong_t)&pmbus_info_one_status},
225 {"bmr480", (kernel_ulong_t)&pmbus_info_one_status},
226 {"bmr490", (kernel_ulong_t)&pmbus_info_one_status},
227 {"bmr491", (kernel_ulong_t)&pmbus_info_one_status},
228 {"bmr492", (kernel_ulong_t)&pmbus_info_one},
229 {"dps460", (kernel_ulong_t)&pmbus_info_one_skip},
230 {"dps650ab", (kernel_ulong_t)&pmbus_info_one_skip},
231 {"dps800", (kernel_ulong_t)&pmbus_info_one_skip},
232 {"max20796", (kernel_ulong_t)&pmbus_info_one},
233 {"mdt040", (kernel_ulong_t)&pmbus_info_one},
234 {"ncp4200", (kernel_ulong_t)&pmbus_info_one},
235 {"ncp4208", (kernel_ulong_t)&pmbus_info_one},
236 {"pdt003", (kernel_ulong_t)&pmbus_info_one},
237 {"pdt006", (kernel_ulong_t)&pmbus_info_one},
238 {"pdt012", (kernel_ulong_t)&pmbus_info_one},
239 {"pmbus", (kernel_ulong_t)&pmbus_info_zero},
240 {"sgd009", (kernel_ulong_t)&pmbus_info_one_skip},
241 {"tps40400", (kernel_ulong_t)&pmbus_info_one},
242 {"tps544b20", (kernel_ulong_t)&pmbus_info_one},
243 {"tps544b25", (kernel_ulong_t)&pmbus_info_one},
244 {"tps544c20", (kernel_ulong_t)&pmbus_info_one},
245 {"tps544c25", (kernel_ulong_t)&pmbus_info_one},
246 {"udt020", (kernel_ulong_t)&pmbus_info_one},
247 {}
248 };
249
250 MODULE_DEVICE_TABLE(i2c, pmbus_id);
251
252 /* This is the driver that will be inserted */
253 static struct i2c_driver pmbus_driver = {
254 .driver = {
255 .name = "pmbus",
256 },
257 .probe = pmbus_probe,
258 .id_table = pmbus_id,
259 };
260
261 module_i2c_driver(pmbus_driver);
262
263 MODULE_AUTHOR("Guenter Roeck");
264 MODULE_DESCRIPTION("Generic PMBus driver");
265 MODULE_LICENSE("GPL");
266 MODULE_IMPORT_NS("PMBUS");
267