1Kernel driver dme1737
   4Supported 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: Available on the Internet
  13  * SMSC SCH5027
  14    Prefix: 'sch5027'
  15    Addresses scanned: I2C 0x2c, 0x2d, 0x2e
  16    Datasheet: Provided by SMSC upon request and under NDA
  17  * SMSC SCH5127
  18    Prefix: 'sch5127'
  19    Addresses scanned: none, address read from Super-I/O config space
  20    Datasheet: Provided by SMSC upon request and under NDA
  23    Juerg Haefliger <>
  26Module Parameters
  29* force_start: bool     Enables the monitoring of voltage, fan and temp inputs
  30                        and PWM output control functions. Using this parameter
  31                        shouldn't be required since the BIOS usually takes care
  32                        of this.
  33* probe_all_addr: bool  Include non-standard LPC addresses 0x162e and 0x164e
  34                        when probing for ISA devices. This is required for the
  35                        following boards:
  36                        - VIA EPIA SN18000
  42This driver implements support for the hardware monitoring capabilities of the
  43SMSC DME1737 and Asus A8000 (which are the same), SMSC SCH5027, SCH311x,
  44and SCH5127 Super-I/O chips. These chips feature monitoring of 3 temp sensors
  45temp[1-3] (2 remote diodes and 1 internal), 7 voltages in[0-6] (6 external and
  461 internal) and up to 6 fan speeds fan[1-6]. Additionally, the chips implement
  47up to 5 PWM outputs pwm[1-3,5-6] for controlling fan speeds both manually and
  50For the DME1737, A8000 and SCH5027, fan[1-2] and pwm[1-2] are always present.
  51Fan[3-6] and pwm[3,5-6] are optional features and their availability depends on
  52the configuration of the chip. The driver will detect which features are
  53present during initialization and create the sysfs attributes accordingly.
  55For the SCH311x and SCH5127, fan[1-3] and pwm[1-3] are always present and
  56fan[4-6] and pwm[5-6] don't exist.
  58The hardware monitoring features of the DME1737, A8000, and SCH5027 are only
  59accessible via SMBus, while the SCH311x and SCH5127 only provide access via
  60the ISA bus. The driver will therefore register itself as an I2C client driver
  61if it detects a DME1737, A8000, or SCH5027 and as a platform driver if it
  62detects a SCH311x or SCH5127 chip.
  65Voltage Monitoring
  68The voltage inputs are sampled with 12-bit resolution and have internal
  69scaling resistors. The values returned by the driver therefore reflect true
  70millivolts and don't need scaling. The voltage inputs are mapped as follows
  71(the last column indicates the input ranges):
  73DME1737, A8000:
  74        in0: +5VTR      (+5V standby)           0V - 6.64V
  75        in1: Vccp       (processor core)        0V - 3V
  76        in2: VCC        (internal +3.3V)        0V - 4.38V
  77        in3: +5V                                0V - 6.64V
  78        in4: +12V                               0V - 16V
  79        in5: VTR        (+3.3V standby)         0V - 4.38V
  80        in6: Vbat       (+3.0V)                 0V - 4.38V
  83        in0: +2.5V                              0V - 3.32V
  84        in1: Vccp       (processor core)        0V - 2V
  85        in2: VCC        (internal +3.3V)        0V - 4.38V
  86        in3: +5V                                0V - 6.64V
  87        in4: +12V                               0V - 16V
  88        in5: VTR        (+3.3V standby)         0V - 4.38V
  89        in6: Vbat       (+3.0V)                 0V - 4.38V
  92        in0: +5VTR      (+5V standby)           0V - 6.64V
  93        in1: Vccp       (processor core)        0V - 3V
  94        in2: VCC        (internal +3.3V)        0V - 4.38V
  95        in3: V2_IN                              0V - 1.5V
  96        in4: V1_IN                              0V - 1.5V
  97        in5: VTR        (+3.3V standby)         0V - 4.38V
  98        in6: Vbat       (+3.0V)                 0V - 4.38V
 101        in0: +2.5                               0V - 3.32V
 102        in1: Vccp       (processor core)        0V - 3V
 103        in2: VCC        (internal +3.3V)        0V - 4.38V
 104        in3: V2_IN                              0V - 1.5V
 105        in4: V1_IN                              0V - 1.5V
 106        in5: VTR        (+3.3V standby)         0V - 4.38V
 107        in6: Vbat       (+3.0V)                 0V - 4.38V
 109Each voltage input has associated min and max limits which trigger an alarm
 110when crossed.
 113Temperature Monitoring
 116Temperatures are measured with 12-bit resolution and reported in millidegree
 117Celsius. The chip also features offsets for all 3 temperature inputs which -
 118when programmed - get added to the input readings. The chip does all the
 119scaling by itself and the driver therefore reports true temperatures that don't
 120need any user-space adjustments. The temperature inputs are mapped as follows
 121(the last column indicates the input ranges):
 123        temp1: Remote diode 1 (3904 type) temperature   -127C - +127C
 124        temp2: DME1737 internal temperature             -127C - +127C
 125        temp3: Remote diode 2 (3904 type) temperature   -127C - +127C
 127Each temperature input has associated min and max limits which trigger an alarm
 128when crossed. Additionally, each temperature input has a fault attribute that
 129returns 1 when a faulty diode or an unconnected input is detected and 0
 133Fan Monitoring
 136Fan RPMs are measured with 16-bit resolution. The chip provides inputs for 6
 137fan tachometers. All 6 inputs have an associated min limit which triggers an
 138alarm when crossed. Fan inputs 1-4 provide type attributes that need to be set
 139to the number of pulses per fan revolution that the connected tachometer
 140generates. Supported values are 1, 2, and 4. Fan inputs 5-6 only support fans
 141that generate 2 pulses per revolution. Fan inputs 5-6 also provide a max
 142attribute that needs to be set to the maximum attainable RPM (fan at 100% duty-
 143cycle) of the input. The chip adjusts the sampling rate based on this value.
 146PWM Output Control
 149This chip features 5 PWM outputs. PWM outputs 1-3 are associated with fan
 150inputs 1-3 and PWM outputs 5-6 are associated with fan inputs 5-6. PWM outputs
 1511-3 can be configured to operate either in manual or automatic mode by setting
 152the appropriate enable attribute accordingly. PWM outputs 5-6 can only operate
 153in manual mode, their enable attributes are therefore read-only. When set to
 154manual mode, the fan speed is set by writing the duty-cycle value to the
 155appropriate PWM attribute. In automatic mode, the PWM attribute returns the
 156current duty-cycle as set by the fan controller in the chip. All PWM outputs
 157support the setting of the output frequency via the freq attribute.
 159In automatic mode, the chip supports the setting of the PWM ramp rate which
 160defines how fast the PWM output is adjusting to changes of the associated
 161temperature input. Associating PWM outputs to temperature inputs is done via
 162temperature zones. The chip features 3 zones whose assignments to temperature
 163inputs is static and determined during initialization. These assignments can
 164be retrieved via the zone[1-3]_auto_channels_temp attributes. Each PWM output
 165is assigned to one (or hottest of multiple) temperature zone(s) through the
 166pwm[1-3]_auto_channels_zone attributes. Each PWM output has 3 distinct output
 167duty-cycles: full, low, and min. Full is internally hard-wired to 255 (100%)
 168and low and min can be programmed via pwm[1-3]_auto_point1_pwm and
 169pwm[1-3]_auto_pwm_min, respectively. The thermal thresholds of the zones are
 170programmed via zone[1-3]_auto_point[1-3]_temp and
 173        pwm[1-3]_auto_point2_pwm        full-speed duty-cycle (255, i.e., 100%)
 174        pwm[1-3]_auto_point1_pwm        low-speed duty-cycle
 175        pwm[1-3]_auto_pwm_min           min-speed duty-cycle
 177        zone[1-3]_auto_point3_temp      full-speed temp (all outputs)
 178        zone[1-3]_auto_point2_temp      full-speed temp
 179        zone[1-3]_auto_point1_temp      low-speed temp
 180        zone[1-3]_auto_point1_temp_hyst min-speed temp
 182The chip adjusts the output duty-cycle linearly in the range of auto_point1_pwm
 183to auto_point2_pwm if the temperature of the associated zone is between
 184auto_point1_temp and auto_point2_temp. If the temperature drops below the
 185auto_point1_temp_hyst value, the output duty-cycle is set to the auto_pwm_min
 186value which only supports two values: 0 or auto_point1_pwm. That means that the
 187fan either turns completely off or keeps spinning with the low-speed
 188duty-cycle. If any of the temperatures rise above the auto_point3_temp value,
 189all PWM outputs are set to 100% duty-cycle.
 191Following is another representation of how the chip sets the output duty-cycle
 192based on the temperature of the associated thermal zone:
 194                        Duty-Cycle      Duty-Cycle
 195        Temperature     Rising Temp     Falling Temp
 196        -----------     -----------     ------------
 197        full-speed      full-speed      full-speed
 199                        < linearly adjusted duty-cycle >
 201        low-speed       low-speed       low-speed
 202                        min-speed       low-speed
 203        min-speed       min-speed       min-speed
 204                        min-speed       min-speed
 207Sysfs Attributes
 210Following is a list of all sysfs attributes that the driver provides, their
 211permissions and a short description:
 213Name                            Perm    Description
 214----                            ----    -----------
 215cpu0_vid                        RO      CPU core reference voltage in
 216                                        millivolts.
 217vrm                             RW      Voltage regulator module version
 218                                        number.
 220in[0-6]_input                   RO      Measured voltage in millivolts.
 221in[0-6]_min                     RW      Low limit for voltage input.
 222in[0-6]_max                     RW      High limit for voltage input.
 223in[0-6]_alarm                   RO      Voltage input alarm. Returns 1 if
 224                                        voltage input is or went outside the
 225                                        associated min-max range, 0 otherwise.
 227temp[1-3]_input                 RO      Measured temperature in millidegree
 228                                        Celsius.
 229temp[1-3]_min                   RW      Low limit for temp input.
 230temp[1-3]_max                   RW      High limit for temp input.
 231temp[1-3]_offset                RW      Offset for temp input. This value will
 232                                        be added by the chip to the measured
 233                                        temperature.
 234temp[1-3]_alarm                 RO      Alarm for temp input. Returns 1 if temp
 235                                        input is or went outside the associated
 236                                        min-max range, 0 otherwise.
 237temp[1-3]_fault                 RO      Temp input fault. Returns 1 if the chip
 238                                        detects a faulty thermal diode or an
 239                                        unconnected temp input, 0 otherwise.
 241zone[1-3]_auto_channels_temp    RO      Temperature zone to temperature input
 242                                        mapping. This attribute is a bitfield
 243                                        and supports the following values:
 244                                                1: temp1
 245                                                2: temp2
 246                                                4: temp3
 247zone[1-3]_auto_point1_temp_hyst RW      Auto PWM temp point1 hysteresis. The
 248                                        output of the corresponding PWM is set
 249                                        to the pwm_auto_min value if the temp
 250                                        falls below the auto_point1_temp_hyst
 251                                        value.
 252zone[1-3]_auto_point[1-3]_temp  RW      Auto PWM temp points. Auto_point1 is
 253                                        the low-speed temp, auto_point2 is the
 254                                        full-speed temp, and auto_point3 is the
 255                                        temp at which all PWM outputs are set
 256                                        to full-speed (100% duty-cycle).
 258fan[1-6]_input                  RO      Measured fan speed in RPM.
 259fan[1-6]_min                    RW      Low limit for fan input.
 260fan[1-6]_alarm                  RO      Alarm for fan input. Returns 1 if fan
 261                                        input is or went below the associated
 262                                        min value, 0 otherwise.
 263fan[1-4]_type                   RW      Type of attached fan. Expressed in
 264                                        number of pulses per revolution that
 265                                        the fan generates. Supported values are
 266                                        1, 2, and 4.
 267fan[5-6]_max                    RW      Max attainable RPM at 100% duty-cycle.
 268                                        Required for chip to adjust the
 269                                        sampling rate accordingly.
 271pmw[1-3,5-6]                    RO/RW   Duty-cycle of PWM output. Supported
 272                                        values are 0-255 (0%-100%). Only
 273                                        writeable if the associated PWM is in
 274                                        manual mode.
 275pwm[1-3]_enable                 RW      Enable of PWM outputs 1-3. Supported
 276                                        values are:
 277                                                 0: turned off (output @ 100%)
 278                                                 1: manual mode
 279                                                 2: automatic mode
 280pwm[5-6]_enable                 RO      Enable of PWM outputs 5-6. Always
 281                                        returns 1 since these 2 outputs are
 282                                        hard-wired to manual mode.
 283pmw[1-3,5-6]_freq               RW      Frequency of PWM output. Supported
 284                                        values are in the range 11Hz-30000Hz
 285                                        (default is 25000Hz).
 286pmw[1-3]_ramp_rate              RW      Ramp rate of PWM output. Determines how
 287                                        fast the PWM duty-cycle will change
 288                                        when the PWM is in automatic mode.
 289                                        Expressed in ms per PWM step. Supported
 290                                        values are in the range 0ms-206ms
 291                                        (default is 0, which means the duty-
 292                                        cycle changes instantly).
 293pwm[1-3]_auto_channels_zone     RW      PWM output to temperature zone mapping.
 294                                        This attribute is a bitfield and
 295                                        supports the following values:
 296                                                1: zone1
 297                                                2: zone2
 298                                                4: zone3
 299                                                6: highest of zone[2-3]
 300                                                7: highest of zone[1-3]
 301pwm[1-3]_auto_pwm_min           RW      Auto PWM min pwm. Minimum PWM duty-
 302                                        cycle. Supported values are 0 or
 303                                        auto_point1_pwm.
 304pwm[1-3]_auto_point1_pwm        RW      Auto PWM pwm point. Auto_point1 is the
 305                                        low-speed duty-cycle.
 306pwm[1-3]_auto_point2_pwm        RO      Auto PWM pwm point. Auto_point2 is the
 307                                        full-speed duty-cycle which is hard-
 308                                        wired to 255 (100% duty-cycle).
 310Chip Differences
 313Feature                 dme1737 sch311x sch5027 sch5127
 315temp[1-3]_offset        yes     yes
 316vid                     yes
 317zone3                   yes     yes     yes
 318zone[1-3]_hyst          yes     yes
 319pwm min/off             yes     yes
 320fan3                    opt     yes     opt     yes
 321pwm3                    opt     yes     opt     yes
 322fan4                    opt             opt
 323fan5                    opt             opt
 324pwm5                    opt             opt
 325fan6                    opt             opt
 326pwm6                    opt             opt