// SPDX-License-Identifier: GPL-2.0+ /* * Hardware monitoring driver for Analog Devices LT7182S * * Copyright (c) 2022 Guenter Roeck * */ #include <linux/bits.h> #include <linux/err.h> #include <linux/i2c.h> #include <linux/init.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/of.h> #include "pmbus.h" #define LT7182S_NUM_PAGES 2 #define MFR_READ_EXTVCC 0xcd #define MFR_READ_ITH 0xce #define MFR_CONFIG_ALL_LT7182S 0xd1 #define MFR_IOUT_PEAK 0xd7 #define MFR_ADC_CONTROL_LT7182S 0xd8 #define MFR_DEBUG_TELEMETRY BIT(0) #define MFR_VOUT_PEAK 0xdd #define MFR_VIN_PEAK 0xde #define MFR_TEMPERATURE_1_PEAK 0xdf #define MFR_CLEAR_PEAKS 0xe3 #define MFR_CONFIG_IEEE BIT(8) static int lt7182s_read_word_data(struct i2c_client *client, int page, int phase, int reg) { int ret; switch (reg) { case PMBUS_VIRT_READ_VMON: if (page == 0 || page == 1) ret = pmbus_read_word_data(client, page, phase, MFR_READ_ITH); else ret = pmbus_read_word_data(client, 0, phase, MFR_READ_EXTVCC); break; case PMBUS_VIRT_READ_IOUT_MAX: ret = pmbus_read_word_data(client, page, phase, MFR_IOUT_PEAK); break; case PMBUS_VIRT_READ_VOUT_MAX: ret = pmbus_read_word_data(client, page, phase, MFR_VOUT_PEAK); break; case PMBUS_VIRT_READ_VIN_MAX: ret = pmbus_read_word_data(client, page, phase, MFR_VIN_PEAK); break; case PMBUS_VIRT_READ_TEMP_MAX: ret = pmbus_read_word_data(client, page, phase, MFR_TEMPERATURE_1_PEAK); break; case PMBUS_VIRT_RESET_VIN_HISTORY: ret = (page == 0) ? 0 : -ENODATA; break; default: ret = -ENODATA; break; } return ret; } static int lt7182s_write_word_data(struct i2c_client *client, int page, int reg, u16 word) { int ret; switch (reg) { case PMBUS_VIRT_RESET_VIN_HISTORY: ret = pmbus_write_byte(client, 0, MFR_CLEAR_PEAKS); break; default: ret = -ENODATA; break; } return ret; } static struct pmbus_driver_info lt7182s_info = { .pages = LT7182S_NUM_PAGES, .format[PSC_VOLTAGE_IN] = linear, .format[PSC_VOLTAGE_OUT] = linear, .format[PSC_CURRENT_IN] = linear, .format[PSC_CURRENT_OUT] = linear, .format[PSC_TEMPERATURE] = linear, .format[PSC_POWER] = linear, .func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT | PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT | PMBUS_HAVE_STATUS_INPUT | PMBUS_HAVE_STATUS_TEMP, .func[1] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_IIN | PMBUS_HAVE_IOUT | PMBUS_HAVE_POUT | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT | PMBUS_HAVE_STATUS_INPUT, .read_word_data = lt7182s_read_word_data, .write_word_data = lt7182s_write_word_data, }; static int lt7182s_probe(struct i2c_client *client) { struct device *dev = &client->dev; struct pmbus_driver_info *info; u8 buf[I2C_SMBUS_BLOCK_MAX + 1]; int ret; if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_BYTE_DATA | I2C_FUNC_SMBUS_READ_WORD_DATA | I2C_FUNC_SMBUS_READ_BLOCK_DATA)) return -ENODEV; ret = i2c_smbus_read_block_data(client, PMBUS_MFR_ID, buf); if (ret < 0) { dev_err(dev, "Failed to read PMBUS_MFR_ID\n"); return ret; } if (ret != 3 || strncmp(buf, "ADI", 3)) { buf[ret] = '\0'; dev_err(dev, "Manufacturer '%s' not supported\n", buf); return -ENODEV; } ret = i2c_smbus_read_block_data(client, PMBUS_MFR_MODEL, buf); if (ret < 0) { dev_err(dev, "Failed to read PMBUS_MFR_MODEL\n"); return ret; } if (ret != 7 || strncmp(buf, "LT7182S", 7)) { buf[ret] = '\0'; dev_err(dev, "Model '%s' not supported\n", buf); return -ENODEV; } info = devm_kmemdup(dev, <7182s_info, sizeof(struct pmbus_driver_info), GFP_KERNEL); if (!info) return -ENOMEM; /* Set data format to IEEE754 if configured */ ret = i2c_smbus_read_word_data(client, MFR_CONFIG_ALL_LT7182S); if (ret < 0) return ret; if (ret & MFR_CONFIG_IEEE) { info->format[PSC_VOLTAGE_IN] = ieee754; info->format[PSC_VOLTAGE_OUT] = ieee754; info->format[PSC_CURRENT_IN] = ieee754; info->format[PSC_CURRENT_OUT] = ieee754; info->format[PSC_TEMPERATURE] = ieee754; info->format[PSC_POWER] = ieee754; } /* Enable VMON output if configured */ ret = i2c_smbus_read_byte_data(client, MFR_ADC_CONTROL_LT7182S); if (ret < 0) return ret; if (ret & MFR_DEBUG_TELEMETRY) { info->pages = 3; info->func[0] |= PMBUS_HAVE_VMON; info->func[1] |= PMBUS_HAVE_VMON; info->func[2] = PMBUS_HAVE_VMON; } return pmbus_do_probe(client, info); } static const struct i2c_device_id lt7182s_id[] = { { "lt7182s", 0 }, {} }; MODULE_DEVICE_TABLE(i2c, lt7182s_id); static const struct of_device_id __maybe_unused lt7182s_of_match[] = { { .compatible = "adi,lt7182s" }, {} }; static struct i2c_driver lt7182s_driver = { .driver = { .name = "lt7182s", .of_match_table = of_match_ptr(lt7182s_of_match), }, .probe = lt7182s_probe, .id_table = lt7182s_id, }; module_i2c_driver(lt7182s_driver); MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>"); MODULE_DESCRIPTION("PMBus driver for Analog Devices LT7182S"); MODULE_LICENSE("GPL"); MODULE_IMPORT_NS(PMBUS);