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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Driver for MPS MP5990 Hot-Swap Controller4 */5 6#include <linux/i2c.h>7#include <linux/module.h>8#include <linux/of_device.h>9#include "pmbus.h"10 11#define MP5990_EFUSE_CFG (0xC4)12#define MP5990_VOUT_FORMAT BIT(9)13 14struct mp5990_data {15 struct pmbus_driver_info info;16 u8 vout_mode;17 u8 vout_linear_exponent;18};19 20#define to_mp5990_data(x) container_of(x, struct mp5990_data, info)21 22static int mp5990_read_byte_data(struct i2c_client *client, int page, int reg)23{24 const struct pmbus_driver_info *info = pmbus_get_driver_info(client);25 struct mp5990_data *data = to_mp5990_data(info);26 27 switch (reg) {28 case PMBUS_VOUT_MODE:29 if (data->vout_mode == linear) {30 /*31 * The VOUT format used by the chip is linear11,32 * not linear16. Report that VOUT is in linear mode33 * and return exponent value extracted while probing34 * the chip.35 */36 return data->vout_linear_exponent;37 }38 39 /*40 * The datasheet does not support the VOUT command,41 * but the device responds with a default value of 0x17.42 * In the standard, 0x17 represents linear mode.43 * Therefore, we should report that VOUT is in direct44 * format when the chip is configured for it.45 */46 return PB_VOUT_MODE_DIRECT;47 48 default:49 return -ENODATA;50 }51}52 53static int mp5990_read_word_data(struct i2c_client *client, int page,54 int phase, int reg)55{56 const struct pmbus_driver_info *info = pmbus_get_driver_info(client);57 struct mp5990_data *data = to_mp5990_data(info);58 int ret;59 s32 mantissa;60 61 switch (reg) {62 case PMBUS_READ_VOUT:63 ret = pmbus_read_word_data(client, page, phase, reg);64 if (ret < 0)65 return ret;66 /*67 * Because the VOUT format used by the chip is linear11 and not68 * linear16, we disregard bits[15:11]. The exponent is reported69 * as part of the VOUT_MODE command.70 */71 if (data->vout_mode == linear) {72 mantissa = ((s16)((ret & 0x7ff) << 5)) >> 5;73 ret = mantissa;74 }75 break;76 default:77 return -ENODATA;78 }79 80 return ret;81}82 83static struct pmbus_driver_info mp5990_info = {84 .pages = 1,85 .format[PSC_VOLTAGE_IN] = direct,86 .format[PSC_VOLTAGE_OUT] = direct,87 .format[PSC_CURRENT_OUT] = direct,88 .format[PSC_POWER] = direct,89 .format[PSC_TEMPERATURE] = direct,90 .m[PSC_VOLTAGE_IN] = 32,91 .b[PSC_VOLTAGE_IN] = 0,92 .R[PSC_VOLTAGE_IN] = 0,93 .m[PSC_VOLTAGE_OUT] = 32,94 .b[PSC_VOLTAGE_OUT] = 0,95 .R[PSC_VOLTAGE_OUT] = 0,96 .m[PSC_CURRENT_OUT] = 16,97 .b[PSC_CURRENT_OUT] = 0,98 .R[PSC_CURRENT_OUT] = 0,99 .m[PSC_POWER] = 1,100 .b[PSC_POWER] = 0,101 .R[PSC_POWER] = 0,102 .m[PSC_TEMPERATURE] = 1,103 .b[PSC_TEMPERATURE] = 0,104 .R[PSC_TEMPERATURE] = 0,105 .func[0] =106 PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_PIN |107 PMBUS_HAVE_TEMP | PMBUS_HAVE_IOUT |108 PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP,109 .read_byte_data = mp5990_read_byte_data,110 .read_word_data = mp5990_read_word_data,111};112 113static int mp5990_probe(struct i2c_client *client)114{115 struct pmbus_driver_info *info;116 struct mp5990_data *data;117 int ret;118 119 data = devm_kzalloc(&client->dev, sizeof(struct mp5990_data),120 GFP_KERNEL);121 if (!data)122 return -ENOMEM;123 124 memcpy(&data->info, &mp5990_info, sizeof(*info));125 info = &data->info;126 127 /* Read Vout Config */128 ret = i2c_smbus_read_word_data(client, MP5990_EFUSE_CFG);129 if (ret < 0) {130 dev_err(&client->dev, "Can't get vout mode.");131 return ret;132 }133 134 /*135 * EFUSE_CFG (0xC4) bit9=1 is linear mode, bit=0 is direct mode.136 */137 if (ret & MP5990_VOUT_FORMAT) {138 data->vout_mode = linear;139 data->info.format[PSC_VOLTAGE_IN] = linear;140 data->info.format[PSC_VOLTAGE_OUT] = linear;141 data->info.format[PSC_CURRENT_OUT] = linear;142 data->info.format[PSC_POWER] = linear;143 ret = i2c_smbus_read_word_data(client, PMBUS_READ_VOUT);144 if (ret < 0) {145 dev_err(&client->dev, "Can't get vout exponent.");146 return ret;147 }148 data->vout_linear_exponent = (u8)((ret >> 11) & 0x1f);149 } else {150 data->vout_mode = direct;151 }152 return pmbus_do_probe(client, info);153}154 155static const struct of_device_id mp5990_of_match[] = {156 { .compatible = "mps,mp5990" },157 {}158};159 160static const struct i2c_device_id mp5990_id[] = {161 {"mp5990"},162 { }163};164MODULE_DEVICE_TABLE(i2c, mp5990_id);165 166static struct i2c_driver mp5990_driver = {167 .driver = {168 .name = "mp5990",169 .of_match_table = mp5990_of_match,170 },171 .probe = mp5990_probe,172 .id_table = mp5990_id,173};174module_i2c_driver(mp5990_driver);175 176MODULE_AUTHOR("Peter Yin <peter.yin@quantatw.com>");177MODULE_DESCRIPTION("PMBus driver for MP5990 HSC");178MODULE_LICENSE("GPL");179MODULE_IMPORT_NS(PMBUS);180