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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Hardware monitoring driver for MPS2856/28574 * Monolithic Power Systems VR Controllers5 *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 0x0d19#define MP2856_MFR_VR_MULTI_CONFIG_R2 0x1d20 21#define MP2856_MUL1_BOOT_SR_R2 0x1022#define MP2856_VR_ACTIVE BIT(15)23 24#define MP2856_MFR_VR_CONFIG2 0x5e25#define MP2856_VOUT_MODE BIT(11)26 27#define MP2856_MFR_VR_CONFIG1 0x6828#define MP2856_DRMOS_KCS GENMASK(13, 12)29 30#define MP2856_MFR_READ_CS1_2_R1 0x8231#define MP2856_MFR_READ_CS3_4_R1 0x8332#define MP2856_MFR_READ_CS5_6_R1 0x8433#define MP2856_MFR_READ_CS7_8_R1 0x8534#define MP2856_MFR_READ_CS9_10_R1 0x8635#define MP2856_MFR_READ_CS11_12_R1 0x8736 37#define MP2856_MFR_READ_CS1_2_R2 0x8538#define MP2856_MFR_READ_CS3_4_R2 0x8639#define MP2856_MFR_READ_CS5_6_R2 0x8740 41#define MP2856_MAX_PHASE_RAIL1 842#define MP2856_MAX_PHASE_RAIL2 443 44#define MP2857_MAX_PHASE_RAIL1 1245#define MP2857_MAX_PHASE_RAIL2 446 47#define MP2856_PAGE_NUM 248 49enum chips { mp2856, mp2857 };50 51static 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 56static const struct i2c_device_id mp2856_id[] = {57 {"mp2856", mp2856},58 {"mp2857", mp2857},59 {}60};61 62MODULE_DEVICE_TABLE(i2c, mp2856_id);63 64struct 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 76static 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 111static int112mp2856_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 120static int121mp2856_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 138static int139mp2856_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 161static int162mp2856_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 205static int206mp2856_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 else221 ret = pmbus_read_word_data(client, page, phase, reg);222 break;223 default:224 return -ENODATA;225 }226 227 return ret;228}229 230static int231mp2856_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 242static int243mp2856_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, PMBUS_PAGE, 2);249 if (ret < 0)250 return ret;251 252 ret = i2c_smbus_read_word_data(client, reg);253 if (ret < 0)254 return ret;255 256 ret &= mask;257 return (ret >= max_phase) ? max_phase : ret;258}259 260static int261mp2856_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 280static int281mp2856_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 300static int301mp2856_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 register308 * 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. Other310 * values are invalid.311 */312 for (i = 0 ; i < data->info.pages; i++) {313 ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, 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 339static int340mp2856_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, PMBUS_PAGE, 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 359static bool360mp2856_is_rail2_active(struct i2c_client *client)361{362 int ret;363 364 ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, 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 375static 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 395static 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(&client->dev, 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, PMBUS_PAGE, 0);441 442 return pmbus_do_probe(client, info);443}444 445static 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};450MODULE_DEVICE_TABLE(of, mp2856_of_match);451 452static 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 461module_i2c_driver(mp2856_driver);462 463MODULE_AUTHOR("Peter Yin <peter.yin@quantatw.com>");464MODULE_DESCRIPTION("PMBus driver for MPS MP2856/MP2857 device");465MODULE_LICENSE("GPL");466MODULE_IMPORT_NS(PMBUS);467