Documentation/hwmon/adm1021

   1 Kernel driver adm1021
   2 =====================
   3
   4 Supported chips:
   5   * Analog Devices ADM1021
   6     Prefix: 'adm1021'
   7     Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
   8     Datasheet: Publicly available at the Analog Devices website
   9   * Analog Devices ADM1021A/ADM1023
  10     Prefix: 'adm1023'
  11     Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
  12     Datasheet: Publicly available at the Analog Devices website
  13   * Genesys Logic GL523SM
  14     Prefix: 'gl523sm'
  15     Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
  16     Datasheet:
  17   * Intel Xeon Processor
  18     Prefix: - any other - may require 'force_adm1021' parameter
  19     Addresses scanned: none
  20     Datasheet: Publicly available at Intel website
  21   * Maxim MAX1617
  22     Prefix: 'max1617'
  23     Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
  24     Datasheet: Publicly available at the Maxim website
  25   * Maxim MAX1617A
  26     Prefix: 'max1617a'
  27     Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
  28     Datasheet: Publicly available at the Maxim website
  29   * National Semiconductor LM84
  30     Prefix: 'lm84'
  31     Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
  32     Datasheet: Publicly available at the National Semiconductor website
  33   * Philips NE1617
  34     Prefix: 'max1617' (probably detected as a max1617)
  35     Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
  36     Datasheet: Publicly available at the Philips website
  37   * Philips NE1617A
  38     Prefix: 'max1617' (probably detected as a max1617)
  39     Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
  40     Datasheet: Publicly available at the Philips website
  41   * TI THMC10
  42     Prefix: 'thmc10'
  43     Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
  44     Datasheet: Publicly available at the TI website
  45   * Onsemi MC1066
  46     Prefix: 'mc1066'
  47     Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
  48     Datasheet: Publicly available at the Onsemi website
  49
  50
  51 Authors:
  52         Frodo Looijaard <frodol@dds.nl>,
  53         Philip Edelbrock <phil@netroedge.com>
  54
  55 Module Parameters
  56 -----------------
  57
  58 * read_only: int
  59   Don't set any values, read only mode
  60
  61
  62 Description
  63 -----------
  64
  65 The chips supported by this driver are very similar. The Maxim MAX1617 is
  66 the oldest; it has the problem that it is not very well detectable. The
  67 MAX1617A solves that. The ADM1021 is a straight clone of the MAX1617A.
  68 Ditto for the THMC10. From here on, we will refer to all these chips as
  69 ADM1021-clones.
  70
  71 The ADM1021 and MAX1617A reports a die code, which is a sort of revision
  72 code. This can help us pinpoint problems; it is not very useful
  73 otherwise.
  74
  75 ADM1021-clones implement two temperature sensors. One of them is internal,
  76 and measures the temperature of the chip itself; the other is external and
  77 is realised in the form of a transistor-like device. A special alarm
  78 indicates whether the remote sensor is connected.
  79
  80 Each sensor has its own low and high limits. When they are crossed, the
  81 corresponding alarm is set and remains on as long as the temperature stays
  82 out of range. Temperatures are measured in degrees Celsius. Measurements
  83 are possible between -65 and +127 degrees, with a resolution of one degree.
  84
  85 If an alarm triggers, it will remain triggered until the hardware register
  86 is read at least once. This means that the cause for the alarm may already
  87 have disappeared!
  88
  89 This driver only updates its values each 1.5 seconds; reading it more often
  90 will do no harm, but will return 'old' values. It is possible to make
  91 ADM1021-clones do faster measurements, but there is really no good reason
  92 for that.
  93
  94 Xeon support
  95 ------------
  96
  97 Some Xeon processors have real max1617, adm1021, or compatible chips
  98 within them, with two temperature sensors.
  99
 100 Other Xeons have chips with only one sensor.
 101
 102 If you have a Xeon, and the adm1021 module loads, and both temperatures
 103 appear valid, then things are good.
 104
 105 If the adm1021 module doesn't load, you should try this:
 106         modprobe adm1021 force_adm1021=BUS,ADDRESS
 107         ADDRESS can only be 0x18, 0x1a, 0x29, 0x2b, 0x4c, or 0x4e.
 108
 109 If you have dual Xeons you may have appear to have two separate
 110 adm1021-compatible chips, or two single-temperature sensors, at distinct
 111 addresses.