1 | // SPDX-License-Identifier: GPL-2.0-or-later |
---|---|
2 | /* |
3 | * Hardware monitoring driver for MPS2856/2857 |
4 | * Monolithic Power Systems VR Controllers |
5 | * |
6 | * Copyright (C) 2023 Quanta Computer lnc. |
7 | */ |
8 | |
9 | #include <linux/err.h> |
10 | #include <linux/i2c.h> |
11 | #include <linux/init.h> |
12 | #include <linux/kernel.h> |
13 | #include <linux/module.h> |
14 | #include <linux/pmbus.h> |
15 | #include "pmbus.h" |
16 | |
17 | /* Vendor specific registers. */ |
18 | #define MP2856_MFR_VR_MULTI_CONFIG_R1 0x0d |
19 | #define MP2856_MFR_VR_MULTI_CONFIG_R2 0x1d |
20 | |
21 | #define MP2856_MUL1_BOOT_SR_R2 0x10 |
22 | #define MP2856_VR_ACTIVE BIT(15) |
23 | |
24 | #define MP2856_MFR_VR_CONFIG2 0x5e |
25 | #define MP2856_VOUT_MODE BIT(11) |
26 | |
27 | #define MP2856_MFR_VR_CONFIG1 0x68 |
28 | #define MP2856_DRMOS_KCS GENMASK(13, 12) |
29 | |
30 | #define MP2856_MFR_READ_CS1_2_R1 0x82 |
31 | #define MP2856_MFR_READ_CS3_4_R1 0x83 |
32 | #define MP2856_MFR_READ_CS5_6_R1 0x84 |
33 | #define MP2856_MFR_READ_CS7_8_R1 0x85 |
34 | #define MP2856_MFR_READ_CS9_10_R1 0x86 |
35 | #define MP2856_MFR_READ_CS11_12_R1 0x87 |
36 | |
37 | #define MP2856_MFR_READ_CS1_2_R2 0x85 |
38 | #define MP2856_MFR_READ_CS3_4_R2 0x86 |
39 | #define MP2856_MFR_READ_CS5_6_R2 0x87 |
40 | |
41 | #define MP2856_MAX_PHASE_RAIL1 8 |
42 | #define MP2856_MAX_PHASE_RAIL2 4 |
43 | |
44 | #define MP2857_MAX_PHASE_RAIL1 12 |
45 | #define MP2857_MAX_PHASE_RAIL2 4 |
46 | |
47 | #define MP2856_PAGE_NUM 2 |
48 | |
49 | enum chips { mp2856, mp2857 }; |
50 | |
51 | static const int mp2856_max_phases[][MP2856_PAGE_NUM] = { |
52 | [mp2856] = { MP2856_MAX_PHASE_RAIL1, MP2856_MAX_PHASE_RAIL2 }, |
53 | [mp2857] = { MP2857_MAX_PHASE_RAIL1, MP2857_MAX_PHASE_RAIL2 }, |
54 | }; |
55 | |
56 | static const struct i2c_device_id mp2856_id[] = { |
57 | {"mp2856", mp2856}, |
58 | {"mp2857", mp2857}, |
59 | {} |
60 | }; |
61 | |
62 | MODULE_DEVICE_TABLE(i2c, mp2856_id); |
63 | |
64 | struct mp2856_data { |
65 | struct pmbus_driver_info info; |
66 | int vout_format[MP2856_PAGE_NUM]; |
67 | int curr_sense_gain[MP2856_PAGE_NUM]; |
68 | int max_phases[MP2856_PAGE_NUM]; |
69 | }; |
70 | |
71 | #define to_mp2856_data(x) container_of(x, struct mp2856_data, info) |
72 | |
73 | #define MAX_LIN_MANTISSA (1023 * 1000) |
74 | #define MIN_LIN_MANTISSA (511 * 1000) |
75 | |
76 | static u16 val2linear11(s64 val) |
77 | { |
78 | s16 exponent = 0, mantissa; |
79 | bool negative = false; |
80 | |
81 | if (val == 0) |
82 | return 0; |
83 | |
84 | if (val < 0) { |
85 | negative = true; |
86 | val = -val; |
87 | } |
88 | |
89 | /* Reduce large mantissa until it fits into 10 bit */ |
90 | while (val >= MAX_LIN_MANTISSA && exponent < 15) { |
91 | exponent++; |
92 | val >>= 1; |
93 | } |
94 | /* Increase small mantissa to improve precision */ |
95 | while (val < MIN_LIN_MANTISSA && exponent > -15) { |
96 | exponent--; |
97 | val <<= 1; |
98 | } |
99 | |
100 | /* Convert mantissa from milli-units to units */ |
101 | mantissa = clamp_val(DIV_ROUND_CLOSEST_ULL(val, 1000), 0, 0x3ff); |
102 | |
103 | /* restore sign */ |
104 | if (negative) |
105 | mantissa = -mantissa; |
106 | |
107 | /* Convert to 5 bit exponent, 11 bit mantissa */ |
108 | return (mantissa & 0x7ff) | ((exponent << 11) & 0xf800); |
109 | } |
110 | |
111 | static int |
112 | mp2856_read_word_helper(struct i2c_client *client, int page, int phase, u8 reg, |
113 | u16 mask) |
114 | { |
115 | int ret = pmbus_read_word_data(client, page, phase, reg); |
116 | |
117 | return (ret > 0) ? ret & mask : ret; |
118 | } |
119 | |
120 | static int |
121 | mp2856_read_vout(struct i2c_client *client, struct mp2856_data *data, int page, |
122 | int phase, u8 reg) |
123 | { |
124 | int ret; |
125 | |
126 | ret = mp2856_read_word_helper(client, page, phase, reg, |
127 | GENMASK(9, 0)); |
128 | if (ret < 0) |
129 | return ret; |
130 | |
131 | /* convert vout result to direct format */ |
132 | ret = (data->vout_format[page] == vid) ? |
133 | ((ret + 49) * 5) : ((ret * 1000) >> 8); |
134 | |
135 | return ret; |
136 | } |
137 | |
138 | static int |
139 | mp2856_read_phase(struct i2c_client *client, struct mp2856_data *data, |
140 | int page, int phase, u8 reg) |
141 | { |
142 | int ret; |
143 | int val; |
144 | |
145 | ret = pmbus_read_word_data(client, page, phase, reg); |
146 | if (ret < 0) |
147 | return ret; |
148 | |
149 | if (!((phase + 1) % MP2856_PAGE_NUM)) |
150 | ret >>= 8; |
151 | ret &= 0xff; |
152 | |
153 | /* |
154 | * Output value is calculated as: (READ_CSx * 12.5mV - 1.23V) / (Kcs * Rcs) |
155 | */ |
156 | val = (ret * 125) - 12300; |
157 | |
158 | return val2linear11(val); |
159 | } |
160 | |
161 | static int |
162 | mp2856_read_phases(struct i2c_client *client, struct mp2856_data *data, |
163 | int page, int phase) |
164 | { |
165 | int ret; |
166 | |
167 | if (page == 0) { |
168 | switch (phase) { |
169 | case 0 ... 1: |
170 | ret = mp2856_read_phase(client, data, page, phase, |
171 | MP2856_MFR_READ_CS1_2_R1); |
172 | break; |
173 | case 2 ... 3: |
174 | ret = mp2856_read_phase(client, data, page, phase, |
175 | MP2856_MFR_READ_CS3_4_R1); |
176 | break; |
177 | case 4 ... 5: |
178 | ret = mp2856_read_phase(client, data, page, phase, |
179 | MP2856_MFR_READ_CS5_6_R1); |
180 | break; |
181 | case 6 ... 7: |
182 | ret = mp2856_read_phase(client, data, page, phase, |
183 | MP2856_MFR_READ_CS7_8_R1); |
184 | break; |
185 | default: |
186 | return -ENODATA; |
187 | } |
188 | } else { |
189 | switch (phase) { |
190 | case 0 ... 1: |
191 | ret = mp2856_read_phase(client, data, page, phase, |
192 | MP2856_MFR_READ_CS1_2_R2); |
193 | break; |
194 | case 2 ... 3: |
195 | ret = mp2856_read_phase(client, data, page, phase, |
196 | MP2856_MFR_READ_CS1_2_R2); |
197 | break; |
198 | default: |
199 | return -ENODATA; |
200 | } |
201 | } |
202 | return ret; |
203 | } |
204 | |
205 | static int |
206 | mp2856_read_word_data(struct i2c_client *client, int page, |
207 | int phase, int reg) |
208 | { |
209 | const struct pmbus_driver_info *info = pmbus_get_driver_info(client); |
210 | struct mp2856_data *data = to_mp2856_data(info); |
211 | int ret; |
212 | |
213 | switch (reg) { |
214 | case PMBUS_READ_VOUT: |
215 | ret = mp2856_read_vout(client, data, page, phase, reg); |
216 | break; |
217 | case PMBUS_READ_IOUT: |
218 | if (phase != 0xff) |
219 | ret = mp2856_read_phases(client, data, page, phase); |
220 | else |
221 | ret = pmbus_read_word_data(client, page, phase, reg); |
222 | break; |
223 | default: |
224 | return -ENODATA; |
225 | } |
226 | |
227 | return ret; |
228 | } |
229 | |
230 | static int |
231 | mp2856_read_byte_data(struct i2c_client *client, int page, int reg) |
232 | { |
233 | switch (reg) { |
234 | case PMBUS_VOUT_MODE: |
235 | /* Enforce VOUT direct format. */ |
236 | return PB_VOUT_MODE_DIRECT; |
237 | default: |
238 | return -ENODATA; |
239 | } |
240 | } |
241 | |
242 | static int |
243 | mp2856_identify_multiphase(struct i2c_client *client, u8 reg, u8 max_phase, |
244 | u16 mask) |
245 | { |
246 | int ret; |
247 | |
248 | ret = i2c_smbus_write_byte_data(client, command: PMBUS_PAGE, value: 2); |
249 | if (ret < 0) |
250 | return ret; |
251 | |
252 | ret = i2c_smbus_read_word_data(client, command: reg); |
253 | if (ret < 0) |
254 | return ret; |
255 | |
256 | ret &= mask; |
257 | return (ret >= max_phase) ? max_phase : ret; |
258 | } |
259 | |
260 | static int |
261 | mp2856_identify_multiphase_rail1(struct i2c_client *client, |
262 | struct mp2856_data *data) |
263 | { |
264 | int ret, i; |
265 | |
266 | ret = mp2856_identify_multiphase(client, MP2856_MFR_VR_MULTI_CONFIG_R1, |
267 | MP2856_MAX_PHASE_RAIL1, GENMASK(3, 0)); |
268 | if (ret < 0) |
269 | return ret; |
270 | |
271 | data->info.phases[0] = (ret > data->max_phases[0]) ? |
272 | data->max_phases[0] : ret; |
273 | |
274 | for (i = 0 ; i < data->info.phases[0]; i++) |
275 | data->info.pfunc[i] |= PMBUS_HAVE_IOUT; |
276 | |
277 | return 0; |
278 | } |
279 | |
280 | static int |
281 | mp2856_identify_multiphase_rail2(struct i2c_client *client, |
282 | struct mp2856_data *data) |
283 | { |
284 | int ret, i; |
285 | |
286 | ret = mp2856_identify_multiphase(client, MP2856_MFR_VR_MULTI_CONFIG_R2, |
287 | MP2856_MAX_PHASE_RAIL2, GENMASK(2, 0)); |
288 | if (ret < 0) |
289 | return ret; |
290 | |
291 | data->info.phases[1] = (ret > data->max_phases[1]) ? |
292 | data->max_phases[1] : ret; |
293 | |
294 | for (i = 0 ; i < data->info.phases[0]; i++) |
295 | data->info.pfunc[i] |= PMBUS_HAVE_IOUT; |
296 | |
297 | return 0; |
298 | } |
299 | |
300 | static int |
301 | mp2856_current_sense_gain_get(struct i2c_client *client, |
302 | struct mp2856_data *data) |
303 | { |
304 | int i, ret; |
305 | |
306 | /* |
307 | * Obtain DrMOS current sense gain of power stage from the register |
308 | * MP2856_MFR_VR_CONFIG1, bits 13-12. The value is selected as below: |
309 | * 00b - 5µA/A, 01b - 8.5µA/A, 10b - 9.7µA/A, 11b - 10µA/A. Other |
310 | * values are invalid. |
311 | */ |
312 | for (i = 0 ; i < data->info.pages; i++) { |
313 | ret = i2c_smbus_write_byte_data(client, command: PMBUS_PAGE, value: i); |
314 | if (ret < 0) |
315 | return ret; |
316 | ret = i2c_smbus_read_word_data(client, |
317 | MP2856_MFR_VR_CONFIG1); |
318 | if (ret < 0) |
319 | return ret; |
320 | |
321 | switch ((ret & MP2856_DRMOS_KCS) >> 12) { |
322 | case 0: |
323 | data->curr_sense_gain[i] = 50; |
324 | break; |
325 | case 1: |
326 | data->curr_sense_gain[i] = 85; |
327 | break; |
328 | case 2: |
329 | data->curr_sense_gain[i] = 97; |
330 | break; |
331 | default: |
332 | data->curr_sense_gain[i] = 100; |
333 | break; |
334 | } |
335 | } |
336 | return 0; |
337 | } |
338 | |
339 | static int |
340 | mp2856_identify_vout_format(struct i2c_client *client, |
341 | struct mp2856_data *data) |
342 | { |
343 | int i, ret; |
344 | |
345 | for (i = 0; i < data->info.pages; i++) { |
346 | ret = i2c_smbus_write_byte_data(client, command: PMBUS_PAGE, value: i); |
347 | if (ret < 0) |
348 | return ret; |
349 | |
350 | ret = i2c_smbus_read_word_data(client, MP2856_MFR_VR_CONFIG2); |
351 | if (ret < 0) |
352 | return ret; |
353 | |
354 | data->vout_format[i] = (ret & MP2856_VOUT_MODE) ? linear : vid; |
355 | } |
356 | return 0; |
357 | } |
358 | |
359 | static bool |
360 | mp2856_is_rail2_active(struct i2c_client *client) |
361 | { |
362 | int ret; |
363 | |
364 | ret = i2c_smbus_write_byte_data(client, command: PMBUS_PAGE, value: 2); |
365 | if (ret < 0) |
366 | return true; |
367 | |
368 | ret = i2c_smbus_read_word_data(client, MP2856_MUL1_BOOT_SR_R2); |
369 | if (ret < 0) |
370 | return true; |
371 | |
372 | return (ret & MP2856_VR_ACTIVE) ? true : false; |
373 | } |
374 | |
375 | static struct pmbus_driver_info mp2856_info = { |
376 | .pages = MP2856_PAGE_NUM, |
377 | .format[PSC_VOLTAGE_IN] = linear, |
378 | .format[PSC_VOLTAGE_OUT] = direct, |
379 | .format[PSC_TEMPERATURE] = linear, |
380 | .format[PSC_CURRENT_IN] = linear, |
381 | .format[PSC_CURRENT_OUT] = linear, |
382 | .format[PSC_POWER] = linear, |
383 | .m[PSC_VOLTAGE_OUT] = 1, |
384 | .R[PSC_VOLTAGE_OUT] = 3, |
385 | .func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT | |
386 | PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT | |
387 | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP | PMBUS_HAVE_POUT | |
388 | PMBUS_HAVE_PIN | PMBUS_HAVE_STATUS_INPUT, |
389 | .func[1] = PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_IOUT | |
390 | PMBUS_HAVE_STATUS_IOUT | PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP, |
391 | .read_byte_data = mp2856_read_byte_data, |
392 | .read_word_data = mp2856_read_word_data, |
393 | }; |
394 | |
395 | static int mp2856_probe(struct i2c_client *client) |
396 | { |
397 | struct pmbus_driver_info *info; |
398 | struct mp2856_data *data; |
399 | enum chips chip_id; |
400 | int ret; |
401 | |
402 | data = devm_kzalloc(dev: &client->dev, size: sizeof(struct mp2856_data), |
403 | GFP_KERNEL); |
404 | if (!data) |
405 | return -ENOMEM; |
406 | |
407 | chip_id = (kernel_ulong_t)i2c_get_match_data(client); |
408 | |
409 | memcpy(data->max_phases, mp2856_max_phases[chip_id], |
410 | sizeof(data->max_phases)); |
411 | |
412 | memcpy(&data->info, &mp2856_info, sizeof(*info)); |
413 | info = &data->info; |
414 | |
415 | /* Identify multiphase configuration. */ |
416 | ret = mp2856_identify_multiphase_rail1(client, data); |
417 | if (ret < 0) |
418 | return ret; |
419 | |
420 | if (mp2856_is_rail2_active(client)) { |
421 | ret = mp2856_identify_multiphase_rail2(client, data); |
422 | if (ret < 0) |
423 | return ret; |
424 | } else { |
425 | /* rail2 is not active */ |
426 | info->pages = 1; |
427 | } |
428 | |
429 | /* Obtain current sense gain of power stage. */ |
430 | ret = mp2856_current_sense_gain_get(client, data); |
431 | if (ret) |
432 | return ret; |
433 | |
434 | /* Identify vout format. */ |
435 | ret = mp2856_identify_vout_format(client, data); |
436 | if (ret) |
437 | return ret; |
438 | |
439 | /* set the device to page 0 */ |
440 | i2c_smbus_write_byte_data(client, command: PMBUS_PAGE, value: 0); |
441 | |
442 | return pmbus_do_probe(client, info); |
443 | } |
444 | |
445 | static const struct of_device_id __maybe_unused mp2856_of_match[] = { |
446 | {.compatible = "mps,mp2856", .data = (void *)mp2856}, |
447 | {.compatible = "mps,mp2857", .data = (void *)mp2857}, |
448 | {} |
449 | }; |
450 | MODULE_DEVICE_TABLE(of, mp2856_of_match); |
451 | |
452 | static struct i2c_driver mp2856_driver = { |
453 | .driver = { |
454 | .name = "mp2856", |
455 | .of_match_table = mp2856_of_match, |
456 | }, |
457 | .probe = mp2856_probe, |
458 | .id_table = mp2856_id, |
459 | }; |
460 | |
461 | module_i2c_driver(mp2856_driver); |
462 | |
463 | MODULE_AUTHOR("Peter Yin <peter.yin@quantatw.com>"); |
464 | MODULE_DESCRIPTION("PMBus driver for MPS MP2856/MP2857 device"); |
465 | MODULE_LICENSE("GPL"); |
466 | MODULE_IMPORT_NS("PMBUS"); |
467 |
Definitions
- chips
- mp2856_max_phases
- mp2856_id
- mp2856_data
- val2linear11
- mp2856_read_word_helper
- mp2856_read_vout
- mp2856_read_phase
- mp2856_read_phases
- mp2856_read_word_data
- mp2856_read_byte_data
- mp2856_identify_multiphase
- mp2856_identify_multiphase_rail1
- mp2856_identify_multiphase_rail2
- mp2856_current_sense_gain_get
- mp2856_identify_vout_format
- mp2856_is_rail2_active
- mp2856_info
- mp2856_probe
- mp2856_of_match
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