1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * Hardware monitoring driver for Maxim MAX16508, MAX16600, MAX16601, |
4 | * and MAX16602. |
5 | * |
6 | * Implementation notes: |
7 | * |
8 | * This chip series supports two rails, VCORE and VSA. Telemetry information |
9 | * for the two rails is reported in two subsequent I2C addresses. The driver |
10 | * instantiates a dummy I2C client at the second I2C address to report |
11 | * information for the VSA rail in a single instance of the driver. |
12 | * Telemetry for the VSA rail is reported to the PMBus core in PMBus page 2. |
13 | * |
14 | * The chip reports input current using two separate methods. The input current |
15 | * reported with the standard READ_IIN command is derived from the output |
16 | * current. The first method is reported to the PMBus core with PMBus page 0, |
17 | * the second method is reported with PMBus page 1. |
18 | * |
19 | * The chip supports reading per-phase temperatures and per-phase input/output |
20 | * currents for VCORE. Telemetry is reported in vendor specific registers. |
21 | * The driver translates the vendor specific register values to PMBus standard |
22 | * register values and reports per-phase information in PMBus page 0. |
23 | * |
24 | * Copyright 2019, 2020 Google LLC. |
25 | */ |
26 | |
27 | #include <linux/bits.h> |
28 | #include <linux/i2c.h> |
29 | #include <linux/init.h> |
30 | #include <linux/kernel.h> |
31 | #include <linux/module.h> |
32 | |
33 | #include "pmbus.h" |
34 | |
35 | enum chips { max16508, max16600, max16601, max16602 }; |
36 | |
37 | #define REG_DEFAULT_NUM_POP 0xc4 |
38 | #define REG_SETPT_DVID 0xd1 |
39 | #define DAC_10MV_MODE BIT(4) |
40 | #define REG_IOUT_AVG_PK 0xee |
41 | #define REG_IIN_SENSOR 0xf1 |
42 | #define REG_TOTAL_INPUT_POWER 0xf2 |
43 | #define REG_PHASE_ID 0xf3 |
44 | #define CORE_RAIL_INDICATOR BIT(7) |
45 | #define REG_PHASE_REPORTING 0xf4 |
46 | |
47 | #define MAX16601_NUM_PHASES 8 |
48 | |
49 | struct max16601_data { |
50 | enum chips id; |
51 | struct pmbus_driver_info info; |
52 | struct i2c_client *vsa; |
53 | int iout_avg_pkg; |
54 | }; |
55 | |
56 | #define to_max16601_data(x) container_of(x, struct max16601_data, info) |
57 | |
58 | static int max16601_read_byte(struct i2c_client *client, int page, int reg) |
59 | { |
60 | const struct pmbus_driver_info *info = pmbus_get_driver_info(client); |
61 | struct max16601_data *data = to_max16601_data(info); |
62 | |
63 | if (page > 0) { |
64 | if (page == 2) /* VSA */ |
65 | return i2c_smbus_read_byte_data(client: data->vsa, command: reg); |
66 | return -EOPNOTSUPP; |
67 | } |
68 | return -ENODATA; |
69 | } |
70 | |
71 | static int max16601_read_word(struct i2c_client *client, int page, int phase, |
72 | int reg) |
73 | { |
74 | const struct pmbus_driver_info *info = pmbus_get_driver_info(client); |
75 | struct max16601_data *data = to_max16601_data(info); |
76 | u8 buf[I2C_SMBUS_BLOCK_MAX + 1]; |
77 | int ret; |
78 | |
79 | switch (page) { |
80 | case 0: /* VCORE */ |
81 | if (phase == 0xff) |
82 | return -ENODATA; |
83 | switch (reg) { |
84 | case PMBUS_READ_IIN: |
85 | case PMBUS_READ_IOUT: |
86 | case PMBUS_READ_TEMPERATURE_1: |
87 | ret = i2c_smbus_write_byte_data(client, REG_PHASE_ID, |
88 | value: phase); |
89 | if (ret) |
90 | return ret; |
91 | ret = i2c_smbus_read_block_data(client, |
92 | REG_PHASE_REPORTING, |
93 | values: buf); |
94 | if (ret < 0) |
95 | return ret; |
96 | if (ret < 6) |
97 | return -EIO; |
98 | switch (reg) { |
99 | case PMBUS_READ_TEMPERATURE_1: |
100 | return buf[1] << 8 | buf[0]; |
101 | case PMBUS_READ_IOUT: |
102 | return buf[3] << 8 | buf[2]; |
103 | case PMBUS_READ_IIN: |
104 | return buf[5] << 8 | buf[4]; |
105 | default: |
106 | break; |
107 | } |
108 | } |
109 | return -EOPNOTSUPP; |
110 | case 1: /* VCORE, read IIN/PIN from sensor element */ |
111 | switch (reg) { |
112 | case PMBUS_READ_IIN: |
113 | return i2c_smbus_read_word_data(client, REG_IIN_SENSOR); |
114 | case PMBUS_READ_PIN: |
115 | return i2c_smbus_read_word_data(client, |
116 | REG_TOTAL_INPUT_POWER); |
117 | default: |
118 | break; |
119 | } |
120 | return -EOPNOTSUPP; |
121 | case 2: /* VSA */ |
122 | switch (reg) { |
123 | case PMBUS_VIRT_READ_IOUT_MAX: |
124 | ret = i2c_smbus_read_word_data(client: data->vsa, |
125 | REG_IOUT_AVG_PK); |
126 | if (ret < 0) |
127 | return ret; |
128 | if (sign_extend32(value: ret, index: 10) > |
129 | sign_extend32(value: data->iout_avg_pkg, index: 10)) |
130 | data->iout_avg_pkg = ret; |
131 | return data->iout_avg_pkg; |
132 | case PMBUS_VIRT_RESET_IOUT_HISTORY: |
133 | return 0; |
134 | case PMBUS_IOUT_OC_FAULT_LIMIT: |
135 | case PMBUS_IOUT_OC_WARN_LIMIT: |
136 | case PMBUS_OT_FAULT_LIMIT: |
137 | case PMBUS_OT_WARN_LIMIT: |
138 | case PMBUS_READ_IIN: |
139 | case PMBUS_READ_IOUT: |
140 | case PMBUS_READ_TEMPERATURE_1: |
141 | case PMBUS_STATUS_WORD: |
142 | return i2c_smbus_read_word_data(client: data->vsa, command: reg); |
143 | default: |
144 | return -EOPNOTSUPP; |
145 | } |
146 | default: |
147 | return -EOPNOTSUPP; |
148 | } |
149 | } |
150 | |
151 | static int max16601_write_byte(struct i2c_client *client, int page, u8 reg) |
152 | { |
153 | const struct pmbus_driver_info *info = pmbus_get_driver_info(client); |
154 | struct max16601_data *data = to_max16601_data(info); |
155 | |
156 | if (page == 2) { |
157 | if (reg == PMBUS_CLEAR_FAULTS) |
158 | return i2c_smbus_write_byte(client: data->vsa, value: reg); |
159 | return -EOPNOTSUPP; |
160 | } |
161 | return -ENODATA; |
162 | } |
163 | |
164 | static int max16601_write_word(struct i2c_client *client, int page, int reg, |
165 | u16 value) |
166 | { |
167 | const struct pmbus_driver_info *info = pmbus_get_driver_info(client); |
168 | struct max16601_data *data = to_max16601_data(info); |
169 | |
170 | switch (page) { |
171 | case 0: /* VCORE */ |
172 | return -ENODATA; |
173 | case 1: /* VCORE IIN/PIN from sensor element */ |
174 | default: |
175 | return -EOPNOTSUPP; |
176 | case 2: /* VSA */ |
177 | switch (reg) { |
178 | case PMBUS_VIRT_RESET_IOUT_HISTORY: |
179 | data->iout_avg_pkg = 0xfc00; |
180 | return 0; |
181 | case PMBUS_IOUT_OC_FAULT_LIMIT: |
182 | case PMBUS_IOUT_OC_WARN_LIMIT: |
183 | case PMBUS_OT_FAULT_LIMIT: |
184 | case PMBUS_OT_WARN_LIMIT: |
185 | return i2c_smbus_write_word_data(client: data->vsa, command: reg, value); |
186 | default: |
187 | return -EOPNOTSUPP; |
188 | } |
189 | } |
190 | } |
191 | |
192 | static int max16601_identify(struct i2c_client *client, |
193 | struct pmbus_driver_info *info) |
194 | { |
195 | struct max16601_data *data = to_max16601_data(info); |
196 | int reg; |
197 | |
198 | reg = i2c_smbus_read_byte_data(client, REG_SETPT_DVID); |
199 | if (reg < 0) |
200 | return reg; |
201 | if (reg & DAC_10MV_MODE) |
202 | info->vrm_version[0] = vr13; |
203 | else |
204 | info->vrm_version[0] = vr12; |
205 | |
206 | if (data->id != max16600 && data->id != max16601 && data->id != max16602) |
207 | return 0; |
208 | |
209 | reg = i2c_smbus_read_byte_data(client, REG_DEFAULT_NUM_POP); |
210 | if (reg < 0) |
211 | return reg; |
212 | |
213 | /* |
214 | * If REG_DEFAULT_NUM_POP returns 0, we don't know how many phases |
215 | * are populated. Stick with the default in that case. |
216 | */ |
217 | reg &= 0x0f; |
218 | if (reg && reg <= MAX16601_NUM_PHASES) |
219 | info->phases[0] = reg; |
220 | |
221 | return 0; |
222 | } |
223 | |
224 | static struct pmbus_driver_info max16601_info = { |
225 | .pages = 3, |
226 | .format[PSC_VOLTAGE_IN] = linear, |
227 | .format[PSC_VOLTAGE_OUT] = vid, |
228 | .format[PSC_CURRENT_IN] = linear, |
229 | .format[PSC_CURRENT_OUT] = linear, |
230 | .format[PSC_TEMPERATURE] = linear, |
231 | .format[PSC_POWER] = linear, |
232 | .func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_IIN | PMBUS_HAVE_PIN | |
233 | PMBUS_HAVE_STATUS_INPUT | |
234 | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT | |
235 | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT | |
236 | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP | |
237 | PMBUS_HAVE_POUT | PMBUS_PAGE_VIRTUAL | PMBUS_PHASE_VIRTUAL, |
238 | .func[1] = PMBUS_HAVE_IIN | PMBUS_HAVE_PIN | PMBUS_PAGE_VIRTUAL, |
239 | .func[2] = PMBUS_HAVE_IIN | PMBUS_HAVE_STATUS_INPUT | |
240 | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT | |
241 | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP | PMBUS_PAGE_VIRTUAL, |
242 | .phases[0] = MAX16601_NUM_PHASES, |
243 | .pfunc[0] = PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT | PMBUS_HAVE_TEMP, |
244 | .pfunc[1] = PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT, |
245 | .pfunc[2] = PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT | PMBUS_HAVE_TEMP, |
246 | .pfunc[3] = PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT, |
247 | .pfunc[4] = PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT | PMBUS_HAVE_TEMP, |
248 | .pfunc[5] = PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT, |
249 | .pfunc[6] = PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT | PMBUS_HAVE_TEMP, |
250 | .pfunc[7] = PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT, |
251 | .identify = max16601_identify, |
252 | .read_byte_data = max16601_read_byte, |
253 | .read_word_data = max16601_read_word, |
254 | .write_byte = max16601_write_byte, |
255 | .write_word_data = max16601_write_word, |
256 | }; |
257 | |
258 | static void max16601_remove(void *_data) |
259 | { |
260 | struct max16601_data *data = _data; |
261 | |
262 | i2c_unregister_device(client: data->vsa); |
263 | } |
264 | |
265 | static const struct i2c_device_id max16601_id[] = { |
266 | {"max16508" , max16508}, |
267 | {"max16600" , max16600}, |
268 | {"max16601" , max16601}, |
269 | {"max16602" , max16602}, |
270 | {} |
271 | }; |
272 | MODULE_DEVICE_TABLE(i2c, max16601_id); |
273 | |
274 | static int max16601_get_id(struct i2c_client *client) |
275 | { |
276 | struct device *dev = &client->dev; |
277 | u8 buf[I2C_SMBUS_BLOCK_MAX + 1]; |
278 | enum chips id; |
279 | int ret; |
280 | |
281 | ret = i2c_smbus_read_block_data(client, command: PMBUS_IC_DEVICE_ID, values: buf); |
282 | if (ret < 0 || ret < 11) |
283 | return -ENODEV; |
284 | |
285 | /* |
286 | * PMBUS_IC_DEVICE_ID is expected to return MAX1660[012]y.xx", |
287 | * "MAX16500y.xx".cdxxcccccccccc, or "MAX16508y.xx". |
288 | */ |
289 | if (!strncmp(buf, "MAX16500" , 8) || !strncmp(buf, "MAX16508" , 8)) { |
290 | id = max16508; |
291 | } else if (!strncmp(buf, "MAX16600" , 8)) { |
292 | id = max16600; |
293 | } else if (!strncmp(buf, "MAX16601" , 8)) { |
294 | id = max16601; |
295 | } else if (!strncmp(buf, "MAX16602" , 8)) { |
296 | id = max16602; |
297 | } else { |
298 | buf[ret] = '\0'; |
299 | dev_err(dev, "Unsupported chip '%s'\n" , buf); |
300 | return -ENODEV; |
301 | } |
302 | return id; |
303 | } |
304 | |
305 | static int max16601_probe(struct i2c_client *client) |
306 | { |
307 | struct device *dev = &client->dev; |
308 | const struct i2c_device_id *id; |
309 | struct max16601_data *data; |
310 | int ret, chip_id; |
311 | |
312 | if (!i2c_check_functionality(adap: client->adapter, |
313 | I2C_FUNC_SMBUS_READ_BYTE_DATA | |
314 | I2C_FUNC_SMBUS_READ_BLOCK_DATA)) |
315 | return -ENODEV; |
316 | |
317 | chip_id = max16601_get_id(client); |
318 | if (chip_id < 0) |
319 | return chip_id; |
320 | |
321 | id = i2c_match_id(id: max16601_id, client); |
322 | if (chip_id != id->driver_data) |
323 | dev_warn(&client->dev, |
324 | "Device mismatch: Configured %s (%d), detected %d\n" , |
325 | id->name, (int) id->driver_data, chip_id); |
326 | |
327 | ret = i2c_smbus_read_byte_data(client, REG_PHASE_ID); |
328 | if (ret < 0) |
329 | return ret; |
330 | if (!(ret & CORE_RAIL_INDICATOR)) { |
331 | dev_err(dev, |
332 | "Driver must be instantiated on CORE rail I2C address\n" ); |
333 | return -ENODEV; |
334 | } |
335 | |
336 | data = devm_kzalloc(dev, size: sizeof(*data), GFP_KERNEL); |
337 | if (!data) |
338 | return -ENOMEM; |
339 | |
340 | data->id = chip_id; |
341 | data->iout_avg_pkg = 0xfc00; |
342 | data->vsa = i2c_new_dummy_device(adapter: client->adapter, address: client->addr + 1); |
343 | if (IS_ERR(ptr: data->vsa)) { |
344 | dev_err(dev, "Failed to register VSA client\n" ); |
345 | return PTR_ERR(ptr: data->vsa); |
346 | } |
347 | ret = devm_add_action_or_reset(dev, max16601_remove, data); |
348 | if (ret) |
349 | return ret; |
350 | |
351 | data->info = max16601_info; |
352 | |
353 | return pmbus_do_probe(client, info: &data->info); |
354 | } |
355 | |
356 | static struct i2c_driver max16601_driver = { |
357 | .driver = { |
358 | .name = "max16601" , |
359 | }, |
360 | .probe = max16601_probe, |
361 | .id_table = max16601_id, |
362 | }; |
363 | |
364 | module_i2c_driver(max16601_driver); |
365 | |
366 | MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>" ); |
367 | MODULE_DESCRIPTION("PMBus driver for Maxim MAX16601" ); |
368 | MODULE_LICENSE("GPL v2" ); |
369 | MODULE_IMPORT_NS(PMBUS); |
370 | |