diff options
Diffstat (limited to 'drivers/hwmon/pmbus/mp2856.c')
| -rw-r--r-- | drivers/hwmon/pmbus/mp2856.c | 466 |
1 files changed, 466 insertions, 0 deletions
diff --git a/drivers/hwmon/pmbus/mp2856.c b/drivers/hwmon/pmbus/mp2856.c new file mode 100644 index 0000000000..6969350f5d --- /dev/null +++ b/drivers/hwmon/pmbus/mp2856.c @@ -0,0 +1,466 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Hardware monitoring driver for MPS2856/2857 + * Monolithic Power Systems VR Controllers + * + * Copyright (C) 2023 Quanta Computer lnc. + */ + +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/pmbus.h> +#include "pmbus.h" + +/* Vendor specific registers. */ +#define MP2856_MFR_VR_MULTI_CONFIG_R1 0x0d +#define MP2856_MFR_VR_MULTI_CONFIG_R2 0x1d + +#define MP2856_MUL1_BOOT_SR_R2 0x10 +#define MP2856_VR_ACTIVE BIT(15) + +#define MP2856_MFR_VR_CONFIG2 0x5e +#define MP2856_VOUT_MODE BIT(11) + +#define MP2856_MFR_VR_CONFIG1 0x68 +#define MP2856_DRMOS_KCS GENMASK(13, 12) + +#define MP2856_MFR_READ_CS1_2_R1 0x82 +#define MP2856_MFR_READ_CS3_4_R1 0x83 +#define MP2856_MFR_READ_CS5_6_R1 0x84 +#define MP2856_MFR_READ_CS7_8_R1 0x85 +#define MP2856_MFR_READ_CS9_10_R1 0x86 +#define MP2856_MFR_READ_CS11_12_R1 0x87 + +#define MP2856_MFR_READ_CS1_2_R2 0x85 +#define MP2856_MFR_READ_CS3_4_R2 0x86 +#define MP2856_MFR_READ_CS5_6_R2 0x87 + +#define MP2856_MAX_PHASE_RAIL1 8 +#define MP2856_MAX_PHASE_RAIL2 4 + +#define MP2857_MAX_PHASE_RAIL1 12 +#define MP2857_MAX_PHASE_RAIL2 4 + +#define MP2856_PAGE_NUM 2 + +enum chips { mp2856 = 1, mp2857 }; + +static const int mp2856_max_phases[][MP2856_PAGE_NUM] = { + [mp2856] = { MP2856_MAX_PHASE_RAIL1, MP2856_MAX_PHASE_RAIL2 }, + [mp2857] = { MP2857_MAX_PHASE_RAIL1, MP2857_MAX_PHASE_RAIL2 }, +}; + +static const struct i2c_device_id mp2856_id[] = { + {"mp2856", mp2856}, + {"mp2857", mp2857}, + {} +}; + +MODULE_DEVICE_TABLE(i2c, mp2856_id); + +struct mp2856_data { + struct pmbus_driver_info info; + int vout_format[MP2856_PAGE_NUM]; + int curr_sense_gain[MP2856_PAGE_NUM]; + int max_phases[MP2856_PAGE_NUM]; + enum chips chip_id; +}; + +#define to_mp2856_data(x) container_of(x, struct mp2856_data, info) + +#define MAX_LIN_MANTISSA (1023 * 1000) +#define MIN_LIN_MANTISSA (511 * 1000) + +static u16 val2linear11(s64 val) +{ + s16 exponent = 0, mantissa; + bool negative = false; + + if (val == 0) + return 0; + + if (val < 0) { + negative = true; + val = -val; + } + + /* Reduce large mantissa until it fits into 10 bit */ + while (val >= MAX_LIN_MANTISSA && exponent < 15) { + exponent++; + val >>= 1; + } + /* Increase small mantissa to improve precision */ + while (val < MIN_LIN_MANTISSA && exponent > -15) { + exponent--; + val <<= 1; + } + + /* Convert mantissa from milli-units to units */ + mantissa = clamp_val(DIV_ROUND_CLOSEST_ULL(val, 1000), 0, 0x3ff); + + /* restore sign */ + if (negative) + mantissa = -mantissa; + + /* Convert to 5 bit exponent, 11 bit mantissa */ + return (mantissa & 0x7ff) | ((exponent << 11) & 0xf800); +} + +static int +mp2856_read_word_helper(struct i2c_client *client, int page, int phase, u8 reg, + u16 mask) +{ + int ret = pmbus_read_word_data(client, page, phase, reg); + + return (ret > 0) ? ret & mask : ret; +} + +static int +mp2856_read_vout(struct i2c_client *client, struct mp2856_data *data, int page, + int phase, u8 reg) +{ + int ret; + + ret = mp2856_read_word_helper(client, page, phase, reg, + GENMASK(9, 0)); + if (ret < 0) + return ret; + + /* convert vout result to direct format */ + ret = (data->vout_format[page] == vid) ? + ((ret + 49) * 5) : ((ret * 1000) >> 8); + + return ret; +} + +static int +mp2856_read_phase(struct i2c_client *client, struct mp2856_data *data, + int page, int phase, u8 reg) +{ + int ret; + int val; + + ret = pmbus_read_word_data(client, page, phase, reg); + if (ret < 0) + return ret; + + if (!((phase + 1) % MP2856_PAGE_NUM)) + ret >>= 8; + ret &= 0xff; + + /* + * Output value is calculated as: (READ_CSx * 12.5mV - 1.23V) / (Kcs * Rcs) + */ + val = (ret * 125) - 12300; + + return val2linear11(val); +} + +static int +mp2856_read_phases(struct i2c_client *client, struct mp2856_data *data, + int page, int phase) +{ + int ret; + + if (page == 0) { + switch (phase) { + case 0 ... 1: + ret = mp2856_read_phase(client, data, page, phase, + MP2856_MFR_READ_CS1_2_R1); + break; + case 2 ... 3: + ret = mp2856_read_phase(client, data, page, phase, + MP2856_MFR_READ_CS3_4_R1); + break; + case 4 ... 5: + ret = mp2856_read_phase(client, data, page, phase, + MP2856_MFR_READ_CS5_6_R1); + break; + case 6 ... 7: + ret = mp2856_read_phase(client, data, page, phase, + MP2856_MFR_READ_CS7_8_R1); + break; + default: + return -ENODATA; + } + } else { + switch (phase) { + case 0 ... 1: + ret = mp2856_read_phase(client, data, page, phase, + MP2856_MFR_READ_CS1_2_R2); + break; + case 2 ... 3: + ret = mp2856_read_phase(client, data, page, phase, + MP2856_MFR_READ_CS1_2_R2); + break; + default: + return -ENODATA; + } + } + return ret; +} + +static int +mp2856_read_word_data(struct i2c_client *client, int page, + int phase, int reg) +{ + const struct pmbus_driver_info *info = pmbus_get_driver_info(client); + struct mp2856_data *data = to_mp2856_data(info); + int ret; + + switch (reg) { + case PMBUS_READ_VOUT: + ret = mp2856_read_vout(client, data, page, phase, reg); + break; + case PMBUS_READ_IOUT: + if (phase != 0xff) + ret = mp2856_read_phases(client, data, page, phase); + else + ret = pmbus_read_word_data(client, page, phase, reg); + break; + default: + return -ENODATA; + } + + return ret; +} + +static int +mp2856_read_byte_data(struct i2c_client *client, int page, int reg) +{ + switch (reg) { + case PMBUS_VOUT_MODE: + /* Enforce VOUT direct format. */ + return PB_VOUT_MODE_DIRECT; + default: + return -ENODATA; + } +} + +static int +mp2856_identify_multiphase(struct i2c_client *client, u8 reg, u8 max_phase, + u16 mask) +{ + int ret; + + ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, 2); + if (ret < 0) + return ret; + + ret = i2c_smbus_read_word_data(client, reg); + if (ret < 0) + return ret; + + ret &= mask; + return (ret >= max_phase) ? max_phase : ret; +} + +static int +mp2856_identify_multiphase_rail1(struct i2c_client *client, + struct mp2856_data *data) +{ + int ret, i; + + ret = mp2856_identify_multiphase(client, MP2856_MFR_VR_MULTI_CONFIG_R1, + MP2856_MAX_PHASE_RAIL1, GENMASK(3, 0)); + if (ret < 0) + return ret; + + data->info.phases[0] = (ret > data->max_phases[0]) ? + data->max_phases[0] : ret; + + for (i = 0 ; i < data->info.phases[0]; i++) + data->info.pfunc[i] |= PMBUS_HAVE_IOUT; + + return 0; +} + +static int +mp2856_identify_multiphase_rail2(struct i2c_client *client, + struct mp2856_data *data) +{ + int ret, i; + + ret = mp2856_identify_multiphase(client, MP2856_MFR_VR_MULTI_CONFIG_R2, + MP2856_MAX_PHASE_RAIL2, GENMASK(2, 0)); + if (ret < 0) + return ret; + + data->info.phases[1] = (ret > data->max_phases[1]) ? + data->max_phases[1] : ret; + + for (i = 0 ; i < data->info.phases[0]; i++) + data->info.pfunc[i] |= PMBUS_HAVE_IOUT; + + return 0; +} + +static int +mp2856_current_sense_gain_get(struct i2c_client *client, + struct mp2856_data *data) +{ + int i, ret; + + /* + * Obtain DrMOS current sense gain of power stage from the register + * MP2856_MFR_VR_CONFIG1, bits 13-12. The value is selected as below: + * 00b - 5µA/A, 01b - 8.5µA/A, 10b - 9.7µA/A, 11b - 10µA/A. Other + * values are invalid. + */ + for (i = 0 ; i < data->info.pages; i++) { + ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, i); + if (ret < 0) + return ret; + ret = i2c_smbus_read_word_data(client, + MP2856_MFR_VR_CONFIG1); + if (ret < 0) + return ret; + + switch ((ret & MP2856_DRMOS_KCS) >> 12) { + case 0: + data->curr_sense_gain[i] = 50; + break; + case 1: + data->curr_sense_gain[i] = 85; + break; + case 2: + data->curr_sense_gain[i] = 97; + break; + default: + data->curr_sense_gain[i] = 100; + break; + } + } + return 0; +} + +static int +mp2856_identify_vout_format(struct i2c_client *client, + struct mp2856_data *data) +{ + int i, ret; + + for (i = 0; i < data->info.pages; i++) { + ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, i); + if (ret < 0) + return ret; + + ret = i2c_smbus_read_word_data(client, MP2856_MFR_VR_CONFIG2); + if (ret < 0) + return ret; + + data->vout_format[i] = (ret & MP2856_VOUT_MODE) ? linear : vid; + } + return 0; +} + +static bool +mp2856_is_rail2_active(struct i2c_client *client) +{ + int ret; + + ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, 2); + if (ret < 0) + return true; + + ret = i2c_smbus_read_word_data(client, MP2856_MUL1_BOOT_SR_R2); + if (ret < 0) + return true; + + return (ret & MP2856_VR_ACTIVE) ? true : false; +} + +static struct pmbus_driver_info mp2856_info = { + .pages = MP2856_PAGE_NUM, + .format[PSC_VOLTAGE_IN] = linear, + .format[PSC_VOLTAGE_OUT] = direct, + .format[PSC_TEMPERATURE] = linear, + .format[PSC_CURRENT_IN] = linear, + .format[PSC_CURRENT_OUT] = linear, + .format[PSC_POWER] = linear, + .m[PSC_VOLTAGE_OUT] = 1, + .R[PSC_VOLTAGE_OUT] = 3, + .func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT | + PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT | + PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP | PMBUS_HAVE_POUT | + PMBUS_HAVE_PIN | PMBUS_HAVE_STATUS_INPUT, + .func[1] = PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_IOUT | + PMBUS_HAVE_STATUS_IOUT | PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP, + .read_byte_data = mp2856_read_byte_data, + .read_word_data = mp2856_read_word_data, +}; + +static int mp2856_probe(struct i2c_client *client) +{ + struct pmbus_driver_info *info; + struct mp2856_data *data; + int ret; + + data = devm_kzalloc(&client->dev, sizeof(struct mp2856_data), + GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->chip_id = (enum chips)(uintptr_t)i2c_get_match_data(client); + + memcpy(data->max_phases, mp2856_max_phases[data->chip_id], + sizeof(data->max_phases)); + + memcpy(&data->info, &mp2856_info, sizeof(*info)); + info = &data->info; + + /* Identify multiphase configuration. */ + ret = mp2856_identify_multiphase_rail1(client, data); + if (ret < 0) + return ret; + + if (mp2856_is_rail2_active(client)) { + ret = mp2856_identify_multiphase_rail2(client, data); + if (ret < 0) + return ret; + } else { + /* rail2 is not active */ + info->pages = 1; + } + + /* Obtain current sense gain of power stage. */ + ret = mp2856_current_sense_gain_get(client, data); + if (ret) + return ret; + + /* Identify vout format. */ + ret = mp2856_identify_vout_format(client, data); + if (ret) + return ret; + + /* set the device to page 0 */ + i2c_smbus_write_byte_data(client, PMBUS_PAGE, 0); + + return pmbus_do_probe(client, info); +} + +static const struct of_device_id __maybe_unused mp2856_of_match[] = { + {.compatible = "mps,mp2856", .data = (void *)mp2856}, + {.compatible = "mps,mp2857", .data = (void *)mp2857}, + {} +}; +MODULE_DEVICE_TABLE(of, mp2856_of_match); + +static struct i2c_driver mp2856_driver = { + .driver = { + .name = "mp2856", + .of_match_table = mp2856_of_match, + }, + .probe = mp2856_probe, + .id_table = mp2856_id, +}; + +module_i2c_driver(mp2856_driver); + +MODULE_AUTHOR("Peter Yin <peter.yin@quantatw.com>"); +MODULE_DESCRIPTION("PMBus driver for MPS MP2856/MP2857 device"); +MODULE_LICENSE("GPL"); +MODULE_IMPORT_NS(PMBUS); |