projects / linux-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 59dfa75e ET |
1 | .. SPDX-License-Identifier: GPL-2.0 |
| 2 | ||
| 3 | Kernel driver tmp513 | |
| 4 | ==================== | |
| 5 | ||
| 6 | Supported chips: | |
| 7 | ||
| 8 | * Texas Instruments TMP512 | |
| 9 | ||
| 10 | Prefix: 'tmp512' | |
| 11 | ||
| 12 | Datasheet: http://www.ti.com/lit/ds/symlink/tmp512.pdf | |
| 13 | ||
| 14 | * Texas Instruments TMP513 | |
| 15 | ||
| 16 | Prefix: 'tmp513' | |
| 17 | ||
| 18 | Datasheet: http://www.ti.com/lit/ds/symlink/tmp513.pdf | |
| 19 | ||
| 20 | Authors: | |
| 21 | ||
| 22 | Eric Tremblay <etremblay@distech-controls.com> | |
| 23 | ||
| 24 | Description | |
| 25 | ----------- | |
| 26 | ||
| 27 | This driver implements support for Texas Instruments TMP512, and TMP513. | |
| 28 | The TMP512 (dual-channel) and TMP513 (triple-channel) are system monitors | |
| 29 | that include remote sensors, a local temperature sensor, and a high-side current | |
| 30 | shunt monitor. These system monitors have the capability of measuring remote | |
| 31 | temperatures, on-chip temperatures, and system voltage/power/current | |
| 32 | consumption. | |
| 33 | ||
| 34 | The temperatures are measured in degrees Celsius with a range of | |
| 35 | -40 to + 125 degrees with a resolution of 0.0625 degree C. | |
| 36 | ||
| 37 | For hysteresis value, only the first channel is writable. Writing to it | |
| 38 | will affect all other values since each channels are sharing the same | |
| 39 | hysteresis value. The hysteresis is in degrees Celsius with a range of | |
| 40 | 0 to 127.5 degrees with a resolution of 0.5 degree. | |
| 41 | ||
| 42 | The driver exports the temperature values via the following sysfs files: | |
| 43 | ||
| 44 | **temp[1-4]_input** | |
| 45 | ||
| 46 | **temp[1-4]_crit** | |
| 47 | ||
| 48 | **temp[1-4]_crit_alarm** | |
| 49 | ||
| 50 | **temp[1-4]_crit_hyst** | |
| 51 | ||
| 52 | The driver read the shunt voltage from the chip and convert it to current. | |
| 53 | The readable range depends on the "ti,pga-gain" property (default to 8) and the | |
| 54 | shunt resistor value. The value resolution will be equal to 10uV/Rshunt. | |
| 55 | ||
| 56 | The driver exports the shunt currents values via the following sysFs files: | |
| 57 | ||
| 58 | **curr1_input** | |
| 59 | ||
| 60 | **curr1_lcrit** | |
| 61 | ||
| 62 | **curr1_lcrit_alarm** | |
| 63 | ||
| 64 | **curr1_crit** | |
| 65 | ||
| 66 | **curr1_crit_alarm** | |
| 67 | ||
| 68 | The bus voltage range is read from the chip with a resolution of 4mV. The chip | |
| 69 | can be configurable in two different range (32V or 16V) using the | |
| 70 | ti,bus-range-microvolt property in the devicetree. | |
| 71 | ||
| 72 | The driver exports the bus voltage values via the following sysFs files: | |
| 73 | ||
| 74 | **in0_input** | |
| 75 | ||
| 76 | **in0_lcrit** | |
| 77 | ||
| 78 | **in0_lcrit_alarm** | |
| 79 | ||
| 80 | **in0_crit** | |
| 81 | ||
| 82 | **in0_crit_alarm** | |
| 83 | ||
| 84 | The bus power and bus currents range and resolution depends on the calibration | |
| 85 | register value. Those values are calculate by the hardware using those | |
| 86 | formulas: | |
| 87 | ||
| 88 | Current = (ShuntVoltage * CalibrationRegister) / 4096 | |
| 89 | Power = (Current * BusVoltage) / 5000 | |
| 90 | ||
| 91 | The driver exports the bus current and bus power values via the following | |
| 92 | sysFs files: | |
| 93 | ||
| 94 | **curr2_input** | |
| 95 | ||
| 96 | **power1_input** | |
| 97 | ||
| 98 | **power1_crit** | |
| 99 | ||
| 100 | **power1_crit_alarm** | |
| 101 | ||
| 102 | The calibration process follow the procedure of the datasheet (without overflow) | |
| 103 | and depend on the shunt resistor value and the pga_gain value. |