1.. SPDX-License-Identifier: GPL-2.0 2 3Kernel driver tvs-mpfs 4====================== 5 6Supported chips: 7 8 * PolarFire SoC 9 10Authors: 11 12 - Conor Dooley <conor.dooley@microchip.com> 13 - Lars Randers <lranders@mail.dk> 14 15Description 16----------- 17 18This driver implements support for the temperature and voltage sensors on 19PolarFire SoC. The temperature reports how hot the die is, and the voltages are 20the SoC's 1.05, 1.8 and 2.5 volt rails respectively. 21 22 23Usage Notes 24----------- 25 26update_interval has a permitted range of 0 to 8 milliseconds. 27 28Temperatures are read in millidegrees Celsius, but the hardware measures in 29degrees Kelvin, storing the result as 11.4 fixed point data, for a maximum 30value of 2047.9375 degrees Kelvin. 31 32Voltages are read in millivolts. The hardware measures in millivolts, storing 33the value as 12.3 fixed point data, for a maximum of 4095.875 millivolts. 34The minimum value reportable by the driver is 0 volts, although the hardware 35is capable of measuring negative values. 36 37Sysfs entries 38------------- 39 40The following attributes are supported. update_interval is read-write, as are 41the enables. All other attributes are read only. 42 43======================= ==================================================== 44temp1_label Fixed name for channel. 45temp1_input Measured temperature for channel. 46temp1_enable Enable/disable for channel. 47 48in[0-2]_label Fixed name for channel. 49in[0-2]_input Measured voltage for channel. 50in[0-2]_enable Enable/disable for channel. 51 52update_interval The interval at which the chip will update readings. 53======================= ==================================================== 54