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authorMauro Carvalho Chehab <mchehab+samsung@kernel.org>2019-04-17 11:46:29 +0200
committerGuenter Roeck <linux@roeck-us.net>2019-04-17 19:37:23 +0200
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parentdocs: hwmon: convert remaining files to ReST format (diff)
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Now that all files were converted to ReST format, rename them and add an index. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
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+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.