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Diffstat (limited to 'kernel/Documentation/hwmon/smsc47m192')
| -rw-r--r-- | kernel/Documentation/hwmon/smsc47m192 | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/kernel/Documentation/hwmon/smsc47m192 b/kernel/Documentation/hwmon/smsc47m192 new file mode 100644 index 000000000..6d54ecb7b --- /dev/null +++ b/kernel/Documentation/hwmon/smsc47m192 @@ -0,0 +1,103 @@ +Kernel driver smsc47m192 +======================== + +Supported chips: + * SMSC LPC47M192, LPC47M15x, LPC47M292 and LPC47M997 + Prefix: 'smsc47m192' + Addresses scanned: I2C 0x2c - 0x2d + Datasheet: The datasheet for LPC47M192 is publicly available from + http://www.smsc.com/ + The LPC47M15x, LPC47M292 and LPC47M997 are compatible for + hardware monitoring. + +Author: Hartmut Rick <linux@rick.claranet.de> + Special thanks to Jean Delvare for careful checking + of the code and many helpful comments and suggestions. + + +Description +----------- + +This driver implements support for the hardware sensor capabilities +of the SMSC LPC47M192 and compatible Super-I/O chips. + +These chips support 3 temperature channels and 8 voltage inputs +as well as CPU voltage VID input. + +They do also have fan monitoring and control capabilities, but the +these features are accessed via ISA bus and are not supported by this +driver. Use the 'smsc47m1' driver for fan monitoring and control. + +Voltages and temperatures are measured by an 8-bit ADC, the resolution +of the temperatures is 1 bit per degree C. +Voltages are scaled such that the nominal voltage corresponds to +192 counts, i.e. 3/4 of the full range. Thus the available range for +each voltage channel is 0V ... 255/192*(nominal voltage), the resolution +is 1 bit per (nominal voltage)/192. +Both voltage and temperature values are scaled by 1000, the sys files +show voltages in mV and temperatures in units of 0.001 degC. + +The +12V analog voltage input channel (in4_input) is multiplexed with +bit 4 of the encoded CPU voltage. This means that you either get +a +12V voltage measurement or a 5 bit CPU VID, but not both. +The default setting is to use the pin as 12V input, and use only 4 bit VID. +This driver assumes that the information in the configuration register +is correct, i.e. that the BIOS has updated the configuration if +the motherboard has this input wired to VID4. + +The temperature and voltage readings are updated once every 1.5 seconds. +Reading them more often repeats the same values. + + +sysfs interface +--------------- + +in0_input - +2.5V voltage input +in1_input - CPU voltage input (nominal 2.25V) +in2_input - +3.3V voltage input +in3_input - +5V voltage input +in4_input - +12V voltage input (may be missing if used as VID4) +in5_input - Vcc voltage input (nominal 3.3V) + This is the supply voltage of the sensor chip itself. +in6_input - +1.5V voltage input +in7_input - +1.8V voltage input + +in[0-7]_min, +in[0-7]_max - lower and upper alarm thresholds for in[0-7]_input reading + + All voltages are read and written in mV. + +in[0-7]_alarm - alarm flags for voltage inputs + These files read '1' in case of alarm, '0' otherwise. + +temp1_input - chip temperature measured by on-chip diode +temp[2-3]_input - temperature measured by external diodes (one of these would + typically be wired to the diode inside the CPU) + +temp[1-3]_min, +temp[1-3]_max - lower and upper alarm thresholds for temperatures + +temp[1-3]_offset - temperature offset registers + The chip adds the offsets stored in these registers to + the corresponding temperature readings. + Note that temp1 and temp2 offsets share the same register, + they cannot both be different from zero at the same time. + Writing a non-zero number to one of them will reset the other + offset to zero. + + All temperatures and offsets are read and written in + units of 0.001 degC. + +temp[1-3]_alarm - alarm flags for temperature inputs, '1' in case of alarm, + '0' otherwise. +temp[2-3]_input_fault - diode fault flags for temperature inputs 2 and 3. + A fault is detected if the two pins for the corresponding + sensor are open or shorted, or any of the two is shorted + to ground or Vcc. '1' indicates a diode fault. + +cpu0_vid - CPU voltage as received from the CPU + +vrm - CPU VID standard used for decoding CPU voltage + + The *_min, *_max, *_offset and vrm files can be read and + written, all others are read-only. |