Signed-off-by: Guenter Roeck <guenter.ro...@ericsson.com> --- Documentation/hwmon/pmbus | 117 +++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 117 insertions(+), 0 deletions(-) create mode 100644 Documentation/hwmon/pmbus
diff --git a/Documentation/hwmon/pmbus b/Documentation/hwmon/pmbus new file mode 100644 index 0000000..7661a35 --- /dev/null +++ b/Documentation/hwmon/pmbus @@ -0,0 +1,117 @@ +Kernel driver pmbus +==================== + +Supported chips: + * Ericsson BMR45X series + DC/DC Converter + Prefix: 'bmr45x' + Addresses scanned: - + Datasheets: Publicly available at the Ericsson website. + * Linear Technology LTC2978 + Octal PMBus Power Supply Monitor and Controller + Prefix: 'ltc2978' + Addresses scanned: - + Datasheet: Publicly available at the Linear Technology website. + * Maxim MAX16064 + Quad Power-Supply Controller + Prefix: 'max16064' + Addresses scanned: - + Datasheet: Publicly available at the Maxim website. + * Maxim MAX8688 + Digital Power-Supply Controller/Monitor + Prefix: 'max8688' + Addresses scanned: - + Datasheet: Publicly available at the Maxim website. + * Texas Instruments UCD92xx + Digital PWM System Controller + Prefix: 'ucd921x', 'ucd9220', 'ucd9240' + Addresses scanned: - + Datasheets: Publicly available at the Philips website. + * Generic PMBus devices + Prefix: 'pmbus' + Addresses scanned: - + Datasheet: n.a. + +Author: Guenter Roeck <guenter.ro...@ericsson.com> + + +Description +----------- + +This driver supports hardware montoring for various PMBus compliant devices. +It supports voltage, current, power, and temperature sensors as supported +by the device. + +Each monitored channel has its own high and low limits, plus a critical +limit. + + +Usage Notes +----------- + +This driver does not probe for PMBus devices, since there is no register +which can be safely used to identify the chip (The MFG_ID register is not +supported by all chips), and since there is no well defined address range for +PMBus devices. You will have to instantiate the devices explicitly. + +Example: the following will load the driver for an LTC2978 at address 0x60 +on I2C bus #1: +$ modprobe pmbus +$ echo ltc2978 0x60 > /sys/bus/i2c/devices/i2c-1/new_device + + +Sysfs entries +------------- + +When probing the chip, the driver identifies which PMBus registers are +supported, and determines available sensors from this information. +Attribute files only exist if respective sensors are suported by the chip. +Labels are provided to inform the user about the sensor associated with +a given sysfs entry. + +The following attributes are supported. Limit attributes are read-write; all +other attributes are read-only. + +inX_input Measured Voltage. From READ_VIN or READ_VOUT register. +inX_min Minumum Voltage. From VIN_UV_WARN_LIMIT or + VOUT_UV_WARN_LIMIT register. +inX_max Maximum Voltage. From VIN_OV_WARN_LIMIT or + VOUT_OV_WARN_LIMIT register. +inX_min_alarm From VOLTAGE_UV_WARNING status. +inX_max_alarm From VOLTAGE_OV_WARNING status. +inX_min_fault From VOLTAGE_UV_FAULT status. +inX_max_fault From VOLTAGE_OV_FAULT status. +inX_label "vin" or "voutY" + +currX_input Measured Current. From READ_IIN or READ_IOUT register. +currX_min Minumum Current. For output current only. + From IOUT_UC_FAULT_LIMIT register. +currX_max Maximum Current. From IIN_OC_WARN_LIMIT or + IOUT_OC_WARN_LIMIT register. +currX_min_alarm For output current only. From IOUT_UC_FAULT status. +currX_max_alarm From IIN_OC_WARNING or IOUT_OC_WARNING status. +currX_label "iin" or "vinY" + +powerX_input Measured Power. From READ_PIN or READ_POUT register. +powerX_cap Power limit. From POUT_MAX register. +powerX_max Power limit. From PIN_OP_WARN_LIMIT or + POUT_OP_WARN_LIMIT register. +powerX_crit Critical power limit. From POUT_OP_FAULT_LIMIT register. +powerX_alarm From POUT_OP_WARNING status. +powerX_label "pin" or "poutY" + +tempX_input Measured tempererature. From READ_TEMPERATURE_X + register. +tempX_min Mimimum tempererature. From UT_WARN_LIMIT register. +tempX_max Maximum tempererature. From OT_WARN_LIMIT register. +tempX_crit Critical high tempererature. From OT_FAULT_LIMIT + register. +tempX_min_alarm Chip temperature low alarm. Set by comparing + READ_TEMPERATURE_X with UT_WARN_LIMIT if + TEMP_UT_WARNING status is set. +tempX_max_alarm Chip temperature high alarm. Set by comparing + READ_TEMPERATURE_X with OT_WARN_LIMIT if + TEMP_OT_WARNING status is set. +tempX_crit_alarm Chip temperature critical alarm. Set by comparing + READ_TEMPERATURE_X with OT_FAULT_LIMIT if + TEMP_OT_FAULT status is set. -- 1.7.0.87.g0901d -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
