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:
  13  * SMSC SCH5027
  14    Prefix: 'sch5027'
  15    Addresses scanned: I2C 0x2c, 0x2d, 0x2e
  16    Datasheet: Provided by SMSC upon request and under NDA
  19    Juerg Haefliger <>
  22Module Parameters
  25* force_start: bool     Enables the monitoring of voltage, fan and temp inputs
  26                        and PWM output control functions. Using this parameter
  27                        shouldn't be required since the BIOS usually takes care
  28                        of this.
  29* probe_all_addr: bool  Include non-standard LPC addresses 0x162e and 0x164e
  30                        when probing for ISA devices. This is required for the
  31                        following boards:
  32                        - VIA EPIA SN18000
  38This driver implements support for the hardware monitoring capabilities of the
  39SMSC DME1737 and Asus A8000 (which are the same), SMSC SCH5027, and SMSC
  40SCH311x Super-I/O chips. These chips feature monitoring of 3 temp sensors
  41temp[1-3] (2 remote diodes and 1 internal), 7 voltages in[0-6] (6 external and
  421 internal) and up to 6 fan speeds fan[1-6]. Additionally, the chips implement
  43up to 5 PWM outputs pwm[1-3,5-6] for controlling fan speeds both manually and
  46For the DME1737, A8000 and SCH5027, fan[1-2] and pwm[1-2] are always present.
  47Fan[3-6] and pwm[3,5-6] are optional features and their availability depends on
  48the configuration of the chip. The driver will detect which features are
  49present during initialization and create the sysfs attributes accordingly.
  51For the SCH311x, fan[1-3] and pwm[1-3] are always present and fan[4-6] and
  52pwm[5-6] don't exist.
  54The hardware monitoring features of the DME1737, A8000, and SCH5027 are only
  55accessible via SMBus, while the SCH311x only provides access via the ISA bus.
  56The driver will therefore register itself as an I2C client driver if it detects
  57a DME1737, A8000, or SCH5027 and as a platform driver if it detects a SCH311x
  61Voltage Monitoring
  64The voltage inputs are sampled with 12-bit resolution and have internal
  65scaling resistors. The values returned by the driver therefore reflect true
  66millivolts and don't need scaling. The voltage inputs are mapped as follows
  67(the last column indicates the input ranges):
  69DME1737, A8000:
  70        in0: +5VTR      (+5V standby)           0V - 6.64V
  71        in1: Vccp       (processor core)        0V - 3V
  72        in2: VCC        (internal +3.3V)        0V - 4.38V
  73        in3: +5V                                0V - 6.64V
  74        in4: +12V                               0V - 16V
  75        in5: VTR        (+3.3V standby)         0V - 4.38V
  76        in6: Vbat       (+3.0V)                 0V - 4.38V
  79        in0: +2.5V                              0V - 6.64V
  80        in1: Vccp       (processor core)        0V - 2V
  81        in2: VCC        (internal +3.3V)        0V - 4.38V
  82        in3: +5V                                0V - 6.64V
  83        in4: +12V                               0V - 16V
  84        in5: VTR        (+3.3V standby)         0V - 4.38V
  85        in6: Vbat       (+3.0V)                 0V - 4.38V
  88        in0: +5VTR      (+5V standby)           0V - 6.64V
  89        in1: Vccp       (processor core)        0V - 3V
  90        in2: VCC        (internal +3.3V)        0V - 4.38V
  91        in3: V2_IN                              0V - 1.5V
  92        in4: V1_IN                              0V - 1.5V
  93        in5: VTR        (+3.3V standby)         0V - 4.38V
  94        in6: Vbat       (+3.0V)                 0V - 4.38V
  96Each voltage input has associated min and max limits which trigger an alarm
  97when crossed.
 100Temperature Monitoring
 103Temperatures are measured with 12-bit resolution and reported in millidegree
 104Celsius. The chip also features offsets for all 3 temperature inputs which -
 105when programmed - get added to the input readings. The chip does all the
 106scaling by itself and the driver therefore reports true temperatures that don't
 107need any user-space adjustments. The temperature inputs are mapped as follows
 108(the last column indicates the input ranges):
 110        temp1: Remote diode 1 (3904 type) temperature   -127C - +127C
 111        temp2: DME1737 internal temperature             -127C - +127C
 112        temp3: Remote diode 2 (3904 type) temperature   -127C - +127C
 114Each temperature input has associated min and max limits which trigger an alarm
 115when crossed. Additionally, each temperature input has a fault attribute that
 116returns 1 when a faulty diode or an unconnected input is detected and 0
 120Fan Monitoring
 123Fan RPMs are measured with 16-bit resolution. The chip provides inputs for 6
 124fan tachometers. All 6 inputs have an associated min limit which triggers an
 125alarm when crossed. Fan inputs 1-4 provide type attributes that need to be set
 126to the number of pulses per fan revolution that the connected tachometer
 127generates. Supported values are 1, 2, and 4. Fan inputs 5-6 only support fans
 128that generate 2 pulses per revolution. Fan inputs 5-6 also provide a max
 129attribute that needs to be set to the maximum attainable RPM (fan at 100% duty-
 130cycle) of the input. The chip adjusts the sampling rate based on this value.
 133PWM Output Control
 136This chip features 5 PWM outputs. PWM outputs 1-3 are associated with fan
 137inputs 1-3 and PWM outputs 5-6 are associated with fan inputs 5-6. PWM outputs
 1381-3 can be configured to operate either in manual or automatic mode by setting
 139the appropriate enable attribute accordingly. PWM outputs 5-6 can only operate
 140in manual mode, their enable attributes are therefore read-only. When set to
 141manual mode, the fan speed is set by writing the duty-cycle value to the
 142appropriate PWM attribute. In automatic mode, the PWM attribute returns the
 143current duty-cycle as set by the fan controller in the chip. All PWM outputs
 144support the setting of the output frequency via the freq attribute.
 146In automatic mode, the chip supports the setting of the PWM ramp rate which
 147defines how fast the PWM output is adjusting to changes of the associated
 148temperature input. Associating PWM outputs to temperature inputs is done via
 149temperature zones. The chip features 3 zones whose assignments to temperature
 150inputs is static and determined during initialization. These assignments can
 151be retrieved via the zone[1-3]_auto_channels_temp attributes. Each PWM output
 152is assigned to one (or hottest of multiple) temperature zone(s) through the
 153pwm[1-3]_auto_channels_zone attributes. Each PWM output has 3 distinct output
 154duty-cycles: full, low, and min. Full is internally hard-wired to 255 (100%)
 155and low and min can be programmed via pwm[1-3]_auto_point1_pwm and
 156pwm[1-3]_auto_pwm_min, respectively. The thermal thresholds of the zones are
 157programmed via zone[1-3]_auto_point[1-3]_temp and
 160        pwm[1-3]_auto_point2_pwm        full-speed duty-cycle (255, i.e., 100%)
 161        pwm[1-3]_auto_point1_pwm        low-speed duty-cycle
 162        pwm[1-3]_auto_pwm_min           min-speed duty-cycle
 164        zone[1-3]_auto_point3_temp      full-speed temp (all outputs)
 165        zone[1-3]_auto_point2_temp      full-speed temp
 166        zone[1-3]_auto_point1_temp      low-speed temp
 167        zone[1-3]_auto_point1_temp_hyst min-speed temp
 169The chip adjusts the output duty-cycle linearly in the range of auto_point1_pwm
 170to auto_point2_pwm if the temperature of the associated zone is between
 171auto_point1_temp and auto_point2_temp. If the temperature drops below the
 172auto_point1_temp_hyst value, the output duty-cycle is set to the auto_pwm_min
 173value which only supports two values: 0 or auto_point1_pwm. That means that the
 174fan either turns completely off or keeps spinning with the low-speed
 175duty-cycle. If any of the temperatures rise above the auto_point3_temp value,
 176all PWM outputs are set to 100% duty-cycle.
 178Following is another representation of how the chip sets the output duty-cycle
 179based on the temperature of the associated thermal zone:
 181                        Duty-Cycle      Duty-Cycle
 182        Temperature     Rising Temp     Falling Temp
 183        -----------     -----------     ------------
 184        full-speed      full-speed      full-speed
 186                        < linearly adjusted duty-cycle >
 188        low-speed       low-speed       low-speed
 189                        min-speed       low-speed
 190        min-speed       min-speed       min-speed
 191                        min-speed       min-speed
 194Sysfs Attributes
 197Following is a list of all sysfs attributes that the driver provides, their
 198permissions and a short description:
 200Name                            Perm    Description
 201----                            ----    -----------
 202cpu0_vid                        RO      CPU core reference voltage in
 203                                        millivolts.
 204vrm                             RW      Voltage regulator module version
 205                                        number.
 207in[0-6]_input                   RO      Measured voltage in millivolts.
 208in[0-6]_min                     RW      Low limit for voltage input.
 209in[0-6]_max                     RW      High limit for voltage input.
 210in[0-6]_alarm                   RO      Voltage input alarm. Returns 1 if
 211                                        voltage input is or went outside the
 212                                        associated min-max range, 0 otherwise.
 214temp[1-3]_input                 RO      Measured temperature in millidegree
 215                                        Celsius.
 216temp[1-3]_min                   RW      Low limit for temp input.
 217temp[1-3]_max                   RW      High limit for temp input.
 218temp[1-3]_offset                RW      Offset for temp input. This value will
 219                                        be added by the chip to the measured
 220                                        temperature.
 221temp[1-3]_alarm                 RO      Alarm for temp input. Returns 1 if temp
 222                                        input is or went outside the associated
 223                                        min-max range, 0 otherwise.
 224temp[1-3]_fault                 RO      Temp input fault. Returns 1 if the chip
 225                                        detects a faulty thermal diode or an
 226                                        unconnected temp input, 0 otherwise.
 228zone[1-3]_auto_channels_temp    RO      Temperature zone to temperature input
 229                                        mapping. This attribute is a bitfield
 230                                        and supports the following values:
 231                                                1: temp1
 232                                                2: temp2
 233                                                4: temp3
 234zone[1-3]_auto_point1_temp_hyst RW      Auto PWM temp point1 hysteresis. The
 235                                        output of the corresponding PWM is set
 236                                        to the pwm_auto_min value if the temp
 237                                        falls below the auto_point1_temp_hyst
 238                                        value.
 239zone[1-3]_auto_point[1-3]_temp  RW      Auto PWM temp points. Auto_point1 is
 240                                        the low-speed temp, auto_point2 is the
 241                                        full-speed temp, and auto_point3 is the
 242                                        temp at which all PWM outputs are set
 243                                        to full-speed (100% duty-cycle).
 245fan[1-6]_input                  RO      Measured fan speed in RPM.
 246fan[1-6]_min                    RW      Low limit for fan input.
 247fan[1-6]_alarm                  RO      Alarm for fan input. Returns 1 if fan
 248                                        input is or went below the associated
 249                                        min value, 0 otherwise.
 250fan[1-4]_type                   RW      Type of attached fan. Expressed in
 251                                        number of pulses per revolution that
 252                                        the fan generates. Supported values are
 253                                        1, 2, and 4.
 254fan[5-6]_max                    RW      Max attainable RPM at 100% duty-cycle.
 255                                        Required for chip to adjust the
 256                                        sampling rate accordingly.
 258pmw[1-3,5-6]                    RO/RW   Duty-cycle of PWM output. Supported
 259                                        values are 0-255 (0%-100%). Only
 260                                        writeable if the associated PWM is in
 261                                        manual mode.
 262pwm[1-3]_enable                 RW      Enable of PWM outputs 1-3. Supported
 263                                        values are:
 264                                                 0: turned off (output @ 100%)
 265                                                 1: manual mode
 266                                                 2: automatic mode
 267pwm[5-6]_enable                 RO      Enable of PWM outputs 5-6. Always
 268                                        returns 1 since these 2 outputs are
 269                                        hard-wired to manual mode.
 270pmw[1-3,5-6]_freq               RW      Frequency of PWM output. Supported
 271                                        values are in the range 11Hz-30000Hz
 272                                        (default is 25000Hz).
 273pmw[1-3]_ramp_rate              RW      Ramp rate of PWM output. Determines how
 274                                        fast the PWM duty-cycle will change
 275                                        when the PWM is in automatic mode.
 276                                        Expressed in ms per PWM step. Supported
 277                                        values are in the range 0ms-206ms
 278                                        (default is 0, which means the duty-
 279                                        cycle changes instantly).
 280pwm[1-3]_auto_channels_zone     RW      PWM output to temperature zone mapping.
 281                                        This attribute is a bitfield and
 282                                        supports the following values:
 283                                                1: zone1
 284                                                2: zone2
 285                                                4: zone3
 286                                                6: highest of zone[2-3]
 287                                                7: highest of zone[1-3]
 288pwm[1-3]_auto_pwm_min           RW      Auto PWM min pwm. Minimum PWM duty-
 289                                        cycle. Supported values are 0 or
 290                                        auto_point1_pwm.
 291pwm[1-3]_auto_point1_pwm        RW      Auto PWM pwm point. Auto_point1 is the
 292                                        low-speed duty-cycle.
 293pwm[1-3]_auto_point2_pwm        RO      Auto PWM pwm point. Auto_point2 is the
 294                                        full-speed duty-cycle which is hard-
 295                                        wired to 255 (100% duty-cycle).