From 8d28cd1b1f56f765dc691eeedf853d41f7aaafd3 Mon Sep 17 00:00:00 2001 From: Guenter Roeck Date: Sat, 22 Aug 2015 00:49:37 -0700 Subject: [PATCH] hwmon: (pmbus) Add client driver for LTC3815 LTC3815 is a Monolithic Synchronous DC/DC Step-Down Converter. Cc: Michael Jones Signed-off-by: Guenter Roeck --- Documentation/hwmon/ltc3815 | 61 ++++++++++ drivers/hwmon/pmbus/Kconfig | 10 ++ drivers/hwmon/pmbus/Makefile | 1 + drivers/hwmon/pmbus/ltc3815.c | 215 ++++++++++++++++++++++++++++++++++ 4 files changed, 287 insertions(+) create mode 100644 Documentation/hwmon/ltc3815 create mode 100644 drivers/hwmon/pmbus/ltc3815.c diff --git a/Documentation/hwmon/ltc3815 b/Documentation/hwmon/ltc3815 new file mode 100644 index 000000000000..eb7db2d13587 --- /dev/null +++ b/Documentation/hwmon/ltc3815 @@ -0,0 +1,61 @@ +Kernel driver ltc3815 +===================== + +Supported chips: + * Linear Technology LTC3815 + Prefix: 'ltc3815' + Addresses scanned: - + Datasheet: http://www.linear.com/product/ltc3815 + +Author: Guenter Roeck + + +Description +----------- + +LTC3815 is a Monolithic Synchronous DC/DC Step-Down Converter. + + +Usage Notes +----------- + +This driver does not probe for PMBus devices. You will have to instantiate +devices explicitly. + +Example: the following commands will load the driver for an LTC3815 +at address 0x20 on I2C bus #1: + +# modprobe ltc3815 +# echo ltc3815 0x20 > /sys/bus/i2c/devices/i2c-1/new_device + + +Sysfs attributes +---------------- + +in1_label "vin" +in1_input Measured input voltage. +in1_alarm Input voltage alarm. +in1_highest Highest input voltage. +in1_reset_history Reset input voltage history. + +in2_label "vout1". +in2_input Measured output voltage. +in2_alarm Output voltage alarm. +in2_highest Highest output voltage. +in2_reset_history Reset output voltage history. + +temp1_input Measured chip temperature. +temp1_alarm Temperature alarm. +temp1_highest Highest measured temperature. +temp1_reset_history Reset temperature history. + +curr1_label "iin". +curr1_input Measured input current. +curr1_highest Highest input current. +curr1_reset_history Reset input current history. + +curr2_label "iout1". +curr2_input Measured output current. +curr2_alarm Output current alarm. +curr2_highest Highest output current. +curr2_reset_history Reset output current history. diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig index df6ebb2b8f0f..7e5cc3d025ef 100644 --- a/drivers/hwmon/pmbus/Kconfig +++ b/drivers/hwmon/pmbus/Kconfig @@ -65,6 +65,16 @@ config SENSORS_LTC2978_REGULATOR If you say yes here you get regulator support for Linear Technology LTC2974, LTC2977, LTC2978, LTC3880, LTC3883, and LTM4676. +config SENSORS_LTC3815 + tristate "Linear Technologies LTC3815" + default n + help + If you say yes here you get hardware monitoring support for Linear + Technology LTC3815. + + This driver can also be built as a module. If so, the module will + be called ltc3815. + config SENSORS_MAX16064 tristate "Maxim MAX16064" default n diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile index bce046d37f02..562132054aaf 100644 --- a/drivers/hwmon/pmbus/Makefile +++ b/drivers/hwmon/pmbus/Makefile @@ -7,6 +7,7 @@ obj-$(CONFIG_SENSORS_PMBUS) += pmbus.o obj-$(CONFIG_SENSORS_ADM1275) += adm1275.o obj-$(CONFIG_SENSORS_LM25066) += lm25066.o obj-$(CONFIG_SENSORS_LTC2978) += ltc2978.o +obj-$(CONFIG_SENSORS_LTC3815) += ltc3815.o obj-$(CONFIG_SENSORS_MAX16064) += max16064.o obj-$(CONFIG_SENSORS_MAX20751) += max20751.o obj-$(CONFIG_SENSORS_MAX34440) += max34440.o diff --git a/drivers/hwmon/pmbus/ltc3815.c b/drivers/hwmon/pmbus/ltc3815.c new file mode 100644 index 000000000000..bb32e6276622 --- /dev/null +++ b/drivers/hwmon/pmbus/ltc3815.c @@ -0,0 +1,215 @@ +/* + * Hardware monitoring driver for LTC3815 + * + * Copyright (c) 2015 Linear Technology + * Copyright (c) 2015 Guenter Roeck + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include +#include +#include +#include +#include +#include +#include "pmbus.h" + +#define LTC3815_MFR_IOUT_PEAK 0xd7 +#define LTC3815_MFR_VOUT_PEAK 0xdd +#define LTC3815_MFR_VIN_PEAK 0xde +#define LTC3815_MFR_TEMP_PEAK 0xdf +#define LTC3815_MFR_IIN_PEAK 0xe1 +#define LTC3815_MFR_SPECIAL_ID 0xe7 + +#define LTC3815_ID 0x8000 +#define LTC3815_ID_MASK 0xff00 + +static int ltc3815_read_byte_data(struct i2c_client *client, int page, int reg) +{ + int ret; + + switch (reg) { + case PMBUS_VOUT_MODE: + /* + * The chip returns 0x3e, suggesting VID mode with manufacturer + * specific VID codes. Since the output voltage is reported + * with a LSB of 0.5mV, override and report direct mode with + * appropriate coefficients. + */ + ret = 0x40; + break; + default: + ret = -ENODATA; + break; + } + return ret; +} + +static int ltc3815_write_byte(struct i2c_client *client, int page, u8 reg) +{ + int ret; + + switch (reg) { + case PMBUS_CLEAR_FAULTS: + /* + * LTC3815 does not support the CLEAR_FAULTS command. + * Emulate it by clearing the status register. + */ + ret = pmbus_read_word_data(client, 0, PMBUS_STATUS_WORD); + if (ret > 0) { + pmbus_write_word_data(client, 0, PMBUS_STATUS_WORD, + ret); + ret = 0; + } + break; + default: + ret = -ENODATA; + break; + } + return ret; +} + +static int ltc3815_read_word_data(struct i2c_client *client, int page, int reg) +{ + int ret; + + switch (reg) { + case PMBUS_VIRT_READ_VIN_MAX: + ret = pmbus_read_word_data(client, page, LTC3815_MFR_VIN_PEAK); + break; + case PMBUS_VIRT_READ_VOUT_MAX: + ret = pmbus_read_word_data(client, page, LTC3815_MFR_VOUT_PEAK); + break; + case PMBUS_VIRT_READ_TEMP_MAX: + ret = pmbus_read_word_data(client, page, LTC3815_MFR_TEMP_PEAK); + break; + case PMBUS_VIRT_READ_IOUT_MAX: + ret = pmbus_read_word_data(client, page, LTC3815_MFR_IOUT_PEAK); + break; + case PMBUS_VIRT_READ_IIN_MAX: + ret = pmbus_read_word_data(client, page, LTC3815_MFR_IIN_PEAK); + break; + case PMBUS_VIRT_RESET_VOUT_HISTORY: + case PMBUS_VIRT_RESET_VIN_HISTORY: + case PMBUS_VIRT_RESET_TEMP_HISTORY: + case PMBUS_VIRT_RESET_IOUT_HISTORY: + case PMBUS_VIRT_RESET_IIN_HISTORY: + ret = 0; + break; + default: + ret = -ENODATA; + break; + } + return ret; +} + +static int ltc3815_write_word_data(struct i2c_client *client, int page, + int reg, u16 word) +{ + int ret; + + switch (reg) { + case PMBUS_VIRT_RESET_IIN_HISTORY: + ret = pmbus_write_word_data(client, page, + LTC3815_MFR_IIN_PEAK, 0); + break; + case PMBUS_VIRT_RESET_IOUT_HISTORY: + ret = pmbus_write_word_data(client, page, + LTC3815_MFR_IOUT_PEAK, 0); + break; + case PMBUS_VIRT_RESET_VOUT_HISTORY: + ret = pmbus_write_word_data(client, page, + LTC3815_MFR_VOUT_PEAK, 0); + break; + case PMBUS_VIRT_RESET_VIN_HISTORY: + ret = pmbus_write_word_data(client, page, + LTC3815_MFR_VIN_PEAK, 0); + break; + case PMBUS_VIRT_RESET_TEMP_HISTORY: + ret = pmbus_write_word_data(client, page, + LTC3815_MFR_TEMP_PEAK, 0); + break; + default: + ret = -ENODATA; + break; + } + return ret; +} + +static const struct i2c_device_id ltc3815_id[] = { + {"ltc3815", 0}, + { } +}; +MODULE_DEVICE_TABLE(i2c, ltc3815_id); + +static struct pmbus_driver_info ltc3815_info = { + .pages = 1, + .format[PSC_VOLTAGE_IN] = direct, + .format[PSC_VOLTAGE_OUT] = direct, + .format[PSC_CURRENT_IN] = direct, + .format[PSC_CURRENT_OUT] = direct, + .format[PSC_TEMPERATURE] = direct, + .m[PSC_VOLTAGE_IN] = 250, + .b[PSC_VOLTAGE_IN] = 0, + .R[PSC_VOLTAGE_IN] = 0, + .m[PSC_VOLTAGE_OUT] = 2, + .b[PSC_VOLTAGE_OUT] = 0, + .R[PSC_VOLTAGE_OUT] = 3, + .m[PSC_CURRENT_IN] = 1, + .b[PSC_CURRENT_IN] = 0, + .R[PSC_CURRENT_IN] = 2, + .m[PSC_CURRENT_OUT] = 1, + .b[PSC_CURRENT_OUT] = 0, + .R[PSC_CURRENT_OUT] = 2, + .m[PSC_TEMPERATURE] = 1, + .b[PSC_TEMPERATURE] = 0, + .R[PSC_TEMPERATURE] = 0, + .func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_IIN | PMBUS_HAVE_VOUT | + PMBUS_HAVE_IOUT | PMBUS_HAVE_TEMP, + .read_byte_data = ltc3815_read_byte_data, + .read_word_data = ltc3815_read_word_data, + .write_byte = ltc3815_write_byte, + .write_word_data = ltc3815_write_word_data, +}; + +static int ltc3815_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + int chip_id; + + if (!i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_READ_WORD_DATA)) + return -ENODEV; + + chip_id = i2c_smbus_read_word_data(client, LTC3815_MFR_SPECIAL_ID); + if (chip_id < 0) + return chip_id; + if ((chip_id & LTC3815_ID_MASK) != LTC3815_ID) + return -ENODEV; + + return pmbus_do_probe(client, id, <c3815_info); +} + +static struct i2c_driver ltc3815_driver = { + .driver = { + .name = "ltc3815", + }, + .probe = ltc3815_probe, + .remove = pmbus_do_remove, + .id_table = ltc3815_id, +}; + +module_i2c_driver(ltc3815_driver); + +MODULE_AUTHOR("Guenter Roeck"); +MODULE_DESCRIPTION("PMBus driver for LTC3815"); +MODULE_LICENSE("GPL");