Documentation/hwmon/dme1737

   1 Kernel driver dme1737
   2 =====================
   3
   4 Supported chips:
   5   * SMSC DME1737 and compatibles (like Asus A8000)
   6     Prefix: 'dme1737'
   7     Addresses scanned: I2C 0x2c, 0x2d, 0x2e
   8     Datasheet: Provided by SMSC upon request and under NDA
   9   * SMSC SCH3112, SCH3114, SCH3116
  10     Prefix: 'sch311x'
  11     Addresses scanned: none, address read from Super-I/O config space
  12     Datasheet: http://www.nuhorizons.com/FeaturedProducts/Volume1/SMSC/311x.pdf
  13
  14 Authors:
  15     Juerg Haefliger <juergh@gmail.com>
  16
  17
  18 Module Parameters
  19 -----------------
  20
  21 * force_start: bool     Enables the monitoring of voltage, fan and temp inputs
  22                         and PWM output control functions. Using this parameter
  23                         shouldn't be required since the BIOS usually takes care
  24                         of this.
  25 * probe_all_addr: bool  Include non-standard LPC addresses 0x162e and 0x164e
  26                         when probing for ISA devices. This is required for the
  27                         following boards:
  28                         - VIA EPIA SN18000
  29
  30 Note that there is no need to use this parameter if the driver loads without
  31 complaining. The driver will say so if it is necessary.
  32
  33
  34 Description
  35 -----------
  36
  37 This driver implements support for the hardware monitoring capabilities of the
  38 SMSC DME1737 and Asus A8000 (which are the same) and SMSC SCH311x Super-I/O
  39 chips. These chips feature monitoring of 3 temp sensors temp[1-3] (2 remote
  40 diodes and 1 internal), 7 voltages in[0-6] (6 external and 1 internal) and up
  41 to 6 fan speeds fan[1-6]. Additionally, the chips implement up to 5 PWM
  42 outputs pwm[1-3,5-6] for controlling fan speeds both manually and
  43 automatically.
  44
  45 For the DME1737 and A8000, fan[1-2] and pwm[1-2] are always present. Fan[3-6]
  46 and pwm[3,5-6] are optional features and their availability depends on the
  47 configuration of the chip. The driver will detect which features are present
  48 during initialization and create the sysfs attributes accordingly.
  49
  50 For the SCH311x, fan[1-3] and pwm[1-3] are always present and fan[4-6] and
  51 pwm[5-6] don't exist.
  52
  53 The hardware monitoring features of the DME1737 and A8000 are only accessible
  54 via SMBus, while the SCH311x only provides access via the ISA bus. The driver
  55 will therefore register itself as an I2C client driver if it detects a DME1737
  56 or A8000 and as a platform driver if it detects a SCH311x chip.
  57
  58
  59 Voltage Monitoring
  60 ------------------
  61
  62 The voltage inputs are sampled with 12-bit resolution and have internal
  63 scaling resistors. The values returned by the driver therefore reflect true
  64 millivolts and don't need scaling. The voltage inputs are mapped as follows
  65 (the last column indicates the input ranges):
  66
  67         in0: +5VTR      (+5V standby)           0V - 6.64V
  68         in1: Vccp       (processor core)        0V - 3V
  69         in2: VCC        (internal +3.3V)        0V - 4.38V
  70         in3: +5V                                0V - 6.64V
  71         in4: +12V                               0V - 16V
  72         in5: VTR        (+3.3V standby)         0V - 4.38V
  73         in6: Vbat       (+3.0V)                 0V - 4.38V
  74
  75 Each voltage input has associated min and max limits which trigger an alarm
  76 when crossed.
  77
  78
  79 Temperature Monitoring
  80 ----------------------
  81
  82 Temperatures are measured with 12-bit resolution and reported in millidegree
  83 Celsius. The chip also features offsets for all 3 temperature inputs which -
  84 when programmed - get added to the input readings. The chip does all the
  85 scaling by itself and the driver therefore reports true temperatures that don't
  86 need any user-space adjustments. The temperature inputs are mapped as follows
  87 (the last column indicates the input ranges):
  88
  89         temp1: Remote diode 1 (3904 type) temperature   -127C - +127C
  90         temp2: DME1737 internal temperature             -127C - +127C
  91         temp3: Remote diode 2 (3904 type) temperature   -127C - +127C
  92
  93 Each temperature input has associated min and max limits which trigger an alarm
  94 when crossed. Additionally, each temperature input has a fault attribute that
  95 returns 1 when a faulty diode or an unconnected input is detected and 0
  96 otherwise.
  97
  98
  99 Fan Monitoring
 100 --------------
 101
 102 Fan RPMs are measured with 16-bit resolution. The chip provides inputs for 6
 103 fan tachometers. All 6 inputs have an associated min limit which triggers an
 104 alarm when crossed. Fan inputs 1-4 provide type attributes that need to be set
 105 to the number of pulses per fan revolution that the connected tachometer
 106 generates. Supported values are 1, 2, and 4. Fan inputs 5-6 only support fans
 107 that generate 2 pulses per revolution. Fan inputs 5-6 also provide a max
 108 attribute that needs to be set to the maximum attainable RPM (fan at 100% duty-
 109 cycle) of the input. The chip adjusts the sampling rate based on this value.
 110
 111
 112 PWM Output Control
 113 ------------------
 114
 115 This chip features 5 PWM outputs. PWM outputs 1-3 are associated with fan
 116 inputs 1-3 and PWM outputs 5-6 are associated with fan inputs 5-6. PWM outputs
 117 1-3 can be configured to operate either in manual or automatic mode by setting
 118 the appropriate enable attribute accordingly. PWM outputs 5-6 can only operate
 119 in manual mode, their enable attributes are therefore read-only. When set to
 120 manual mode, the fan speed is set by writing the duty-cycle value to the
 121 appropriate PWM attribute. In automatic mode, the PWM attribute returns the
 122 current duty-cycle as set by the fan controller in the chip. All PWM outputs
 123 support the setting of the output frequency via the freq attribute.
 124
 125 In automatic mode, the chip supports the setting of the PWM ramp rate which
 126 defines how fast the PWM output is adjusting to changes of the associated
 127 temperature input. Associating PWM outputs to temperature inputs is done via
 128 temperature zones. The chip features 3 zones whose assignments to temperature
 129 inputs is static and determined during initialization. These assignments can
 130 be retrieved via the zone[1-3]_auto_channels_temp attributes. Each PWM output
 131 is assigned to one (or hottest of multiple) temperature zone(s) through the
 132 pwm[1-3]_auto_channels_zone attributes. Each PWM output has 3 distinct output
 133 duty-cycles: full, low, and min. Full is internally hard-wired to 255 (100%)
 134 and low and min can be programmed via pwm[1-3]_auto_point1_pwm and
 135 pwm[1-3]_auto_pwm_min, respectively. The thermal thresholds of the zones are
 136 programmed via zone[1-3]_auto_point[1-3]_temp and
 137 zone[1-3]_auto_point1_temp_hyst:
 138
 139         pwm[1-3]_auto_point2_pwm        full-speed duty-cycle (255, i.e., 100%)
 140         pwm[1-3]_auto_point1_pwm        low-speed duty-cycle
 141         pwm[1-3]_auto_pwm_min           min-speed duty-cycle
 142
 143         zone[1-3]_auto_point3_temp      full-speed temp (all outputs)
 144         zone[1-3]_auto_point2_temp      full-speed temp
 145         zone[1-3]_auto_point1_temp      low-speed temp
 146         zone[1-3]_auto_point1_temp_hyst min-speed temp
 147
 148 The chip adjusts the output duty-cycle linearly in the range of auto_point1_pwm
 149 to auto_point2_pwm if the temperature of the associated zone is between
 150 auto_point1_temp and auto_point2_temp. If the temperature drops below the
 151 auto_point1_temp_hyst value, the output duty-cycle is set to the auto_pwm_min
 152 value which only supports two values: 0 or auto_point1_pwm. That means that the
 153 fan either turns completely off or keeps spinning with the low-speed
 154 duty-cycle. If any of the temperatures rise above the auto_point3_temp value,
 155 all PWM outputs are set to 100% duty-cycle.
 156
 157 Following is another representation of how the chip sets the output duty-cycle
 158 based on the temperature of the associated thermal zone:
 159
 160                         Duty-Cycle      Duty-Cycle
 161         Temperature     Rising Temp     Falling Temp
 162         -----------     -----------     ------------
 163         full-speed      full-speed      full-speed
 164
 165                         < linearly adjusted duty-cycle >
 166
 167         low-speed       low-speed       low-speed
 168                         min-speed       low-speed
 169         min-speed       min-speed       min-speed
 170                         min-speed       min-speed
 171
 172
 173 Sysfs Attributes
 174 ----------------
 175
 176 Following is a list of all sysfs attributes that the driver provides, their
 177 permissions and a short description:
 178
 179 Name                            Perm    Description
 180 ----                            ----    -----------
 181 cpu0_vid                        RO      CPU core reference voltage in
 182                                         millivolts.
 183 vrm                             RW      Voltage regulator module version
 184                                         number.
 185
 186 in[0-6]_input                   RO      Measured voltage in millivolts.
 187 in[0-6]_min                     RW      Low limit for voltage input.
 188 in[0-6]_max                     RW      High limit for voltage input.
 189 in[0-6]_alarm                   RO      Voltage input alarm. Returns 1 if
 190                                         voltage input is or went outside the
 191                                         associated min-max range, 0 otherwise.
 192
 193 temp[1-3]_input                 RO      Measured temperature in millidegree
 194                                         Celsius.
 195 temp[1-3]_min                   RW      Low limit for temp input.
 196 temp[1-3]_max                   RW      High limit for temp input.
 197 temp[1-3]_offset                RW      Offset for temp input. This value will
 198                                         be added by the chip to the measured
 199                                         temperature.
 200 temp[1-3]_alarm                 RO      Alarm for temp input. Returns 1 if temp
 201                                         input is or went outside the associated
 202                                         min-max range, 0 otherwise.
 203 temp[1-3]_fault                 RO      Temp input fault. Returns 1 if the chip
 204                                         detects a faulty thermal diode or an
 205                                         unconnected temp input, 0 otherwise.
 206
 207 zone[1-3]_auto_channels_temp    RO      Temperature zone to temperature input
 208                                         mapping. This attribute is a bitfield
 209                                         and supports the following values:
 210                                                 1: temp1
 211                                                 2: temp2
 212                                                 4: temp3
 213 zone[1-3]_auto_point1_temp_hyst RW      Auto PWM temp point1 hysteresis. The
 214                                         output of the corresponding PWM is set
 215                                         to the pwm_auto_min value if the temp
 216                                         falls below the auto_point1_temp_hyst
 217                                         value.
 218 zone[1-3]_auto_point[1-3]_temp  RW      Auto PWM temp points. Auto_point1 is
 219                                         the low-speed temp, auto_point2 is the
 220                                         full-speed temp, and auto_point3 is the
 221                                         temp at which all PWM outputs are set
 222                                         to full-speed (100% duty-cycle).
 223
 224 fan[1-6]_input                  RO      Measured fan speed in RPM.
 225 fan[1-6]_min                    RW      Low limit for fan input.
 226 fan[1-6]_alarm                  RO      Alarm for fan input. Returns 1 if fan
 227                                         input is or went below the associated
 228                                         min value, 0 otherwise.
 229 fan[1-4]_type                   RW      Type of attached fan. Expressed in
 230                                         number of pulses per revolution that
 231                                         the fan generates. Supported values are
 232                                         1, 2, and 4.
 233 fan[5-6]_max                    RW      Max attainable RPM at 100% duty-cycle.
 234                                         Required for chip to adjust the
 235                                         sampling rate accordingly.
 236
 237 pmw[1-3,5-6]                    RO/RW   Duty-cycle of PWM output. Supported
 238                                         values are 0-255 (0%-100%). Only
 239                                         writeable if the associated PWM is in
 240                                         manual mode.
 241 pwm[1-3]_enable                 RW      Enable of PWM outputs 1-3. Supported
 242                                         values are:
 243                                                  0: turned off (output @ 100%)
 244                                                  1: manual mode
 245                                                  2: automatic mode
 246 pwm[5-6]_enable                 RO      Enable of PWM outputs 5-6. Always
 247                                         returns 1 since these 2 outputs are
 248                                         hard-wired to manual mode.
 249 pmw[1-3,5-6]_freq               RW      Frequency of PWM output. Supported
 250                                         values are in the range 11Hz-30000Hz
 251                                         (default is 25000Hz).
 252 pmw[1-3]_ramp_rate              RW      Ramp rate of PWM output. Determines how
 253                                         fast the PWM duty-cycle will change
 254                                         when the PWM is in automatic mode.
 255                                         Expressed in ms per PWM step. Supported
 256                                         values are in the range 0ms-206ms
 257                                         (default is 0, which means the duty-
 258                                         cycle changes instantly).
 259 pwm[1-3]_auto_channels_zone     RW      PWM output to temperature zone mapping.
 260                                         This attribute is a bitfield and
 261                                         supports the following values:
 262                                                 1: zone1
 263                                                 2: zone2
 264                                                 4: zone3
 265                                                 6: highest of zone[2-3]
 266                                                 7: highest of zone[1-3]
 267 pwm[1-3]_auto_pwm_min           RW      Auto PWM min pwm. Minimum PWM duty-
 268                                         cycle. Supported values are 0 or
 269                                         auto_point1_pwm.
 270 pwm[1-3]_auto_point1_pwm        RW      Auto PWM pwm point. Auto_point1 is the
 271                                         low-speed duty-cycle.
 272 pwm[1-3]_auto_point2_pwm        RO      Auto PWM pwm point. Auto_point2 is the
 273                                         full-speed duty-cycle which is hard-
 274                                         wired to 255 (100% duty-cycle).