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   * SMSC SCH5027
  14     Prefix: 'sch5027'
  15     Addresses scanned: I2C 0x2c, 0x2d, 0x2e
  16     Datasheet: Provided by SMSC upon request and under NDA
  17
  18 Authors:
  19     Juerg Haefliger <juergh@gmail.com>
  20
  21
  22 Module Parameters
  23 -----------------
  24
  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
  33
  34
  35 Description
  36 -----------
  37
  38 This driver implements support for the hardware monitoring capabilities of the
  39 SMSC DME1737 and Asus A8000 (which are the same), SMSC SCH5027, and SMSC
  40 SCH311x Super-I/O chips. These chips feature monitoring of 3 temp sensors
  41 temp[1-3] (2 remote diodes and 1 internal), 7 voltages in[0-6] (6 external and
  42 1 internal) and up to 6 fan speeds fan[1-6]. Additionally, the chips implement
  43 up to 5 PWM outputs pwm[1-3,5-6] for controlling fan speeds both manually and
  44 automatically.
  45
  46 For the DME1737, A8000 and SCH5027, fan[1-2] and pwm[1-2] are always present.
  47 Fan[3-6] and pwm[3,5-6] are optional features and their availability depends on
  48 the configuration of the chip. The driver will detect which features are
  49 present during initialization and create the sysfs attributes accordingly.
  50
  51 For the SCH311x, fan[1-3] and pwm[1-3] are always present and fan[4-6] and
  52 pwm[5-6] don't exist.
  53
  54 The hardware monitoring features of the DME1737, A8000, and SCH5027 are only
  55 accessible via SMBus, while the SCH311x only provides access via the ISA bus.
  56 The driver will therefore register itself as an I2C client driver if it detects
  57 a DME1737, A8000, or SCH5027 and as a platform driver if it detects a SCH311x
  58 chip.
  59
  60
  61 Voltage Monitoring
  62 ------------------
  63
  64 The voltage inputs are sampled with 12-bit resolution and have internal
  65 scaling resistors. The values returned by the driver therefore reflect true
  66 millivolts and don't need scaling. The voltage inputs are mapped as follows
  67 (the last column indicates the input ranges):
  68
  69 DME1737, 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
  77
  78 SCH311x:
  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
  86
  87 SCH5027:
  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
  95
  96 Each voltage input has associated min and max limits which trigger an alarm
  97 when crossed.
  98
  99
 100 Temperature Monitoring
 101 ----------------------
 102
 103 Temperatures are measured with 12-bit resolution and reported in millidegree
 104 Celsius. The chip also features offsets for all 3 temperature inputs which -
 105 when programmed - get added to the input readings. The chip does all the
 106 scaling by itself and the driver therefore reports true temperatures that don't
 107 need any user-space adjustments. The temperature inputs are mapped as follows
 108 (the last column indicates the input ranges):
 109
 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
 113
 114 Each temperature input has associated min and max limits which trigger an alarm
 115 when crossed. Additionally, each temperature input has a fault attribute that
 116 returns 1 when a faulty diode or an unconnected input is detected and 0
 117 otherwise.
 118
 119
 120 Fan Monitoring
 121 --------------
 122
 123 Fan RPMs are measured with 16-bit resolution. The chip provides inputs for 6
 124 fan tachometers. All 6 inputs have an associated min limit which triggers an
 125 alarm when crossed. Fan inputs 1-4 provide type attributes that need to be set
 126 to the number of pulses per fan revolution that the connected tachometer
 127 generates. Supported values are 1, 2, and 4. Fan inputs 5-6 only support fans
 128 that generate 2 pulses per revolution. Fan inputs 5-6 also provide a max
 129 attribute that needs to be set to the maximum attainable RPM (fan at 100% duty-
 130 cycle) of the input. The chip adjusts the sampling rate based on this value.
 131
 132
 133 PWM Output Control
 134 ------------------
 135
 136 This chip features 5 PWM outputs. PWM outputs 1-3 are associated with fan
 137 inputs 1-3 and PWM outputs 5-6 are associated with fan inputs 5-6. PWM outputs
 138 1-3 can be configured to operate either in manual or automatic mode by setting
 139 the appropriate enable attribute accordingly. PWM outputs 5-6 can only operate
 140 in manual mode, their enable attributes are therefore read-only. When set to
 141 manual mode, the fan speed is set by writing the duty-cycle value to the
 142 appropriate PWM attribute. In automatic mode, the PWM attribute returns the
 143 current duty-cycle as set by the fan controller in the chip. All PWM outputs
 144 support the setting of the output frequency via the freq attribute.
 145
 146 In automatic mode, the chip supports the setting of the PWM ramp rate which
 147 defines how fast the PWM output is adjusting to changes of the associated
 148 temperature input. Associating PWM outputs to temperature inputs is done via
 149 temperature zones. The chip features 3 zones whose assignments to temperature
 150 inputs is static and determined during initialization. These assignments can
 151 be retrieved via the zone[1-3]_auto_channels_temp attributes. Each PWM output
 152 is assigned to one (or hottest of multiple) temperature zone(s) through the
 153 pwm[1-3]_auto_channels_zone attributes. Each PWM output has 3 distinct output
 154 duty-cycles: full, low, and min. Full is internally hard-wired to 255 (100%)
 155 and low and min can be programmed via pwm[1-3]_auto_point1_pwm and
 156 pwm[1-3]_auto_pwm_min, respectively. The thermal thresholds of the zones are
 157 programmed via zone[1-3]_auto_point[1-3]_temp and
 158 zone[1-3]_auto_point1_temp_hyst:
 159
 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
 163
 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
 168
 169 The chip adjusts the output duty-cycle linearly in the range of auto_point1_pwm
 170 to auto_point2_pwm if the temperature of the associated zone is between
 171 auto_point1_temp and auto_point2_temp. If the temperature drops below the
 172 auto_point1_temp_hyst value, the output duty-cycle is set to the auto_pwm_min
 173 value which only supports two values: 0 or auto_point1_pwm. That means that the
 174 fan either turns completely off or keeps spinning with the low-speed
 175 duty-cycle. If any of the temperatures rise above the auto_point3_temp value,
 176 all PWM outputs are set to 100% duty-cycle.
 177
 178 Following is another representation of how the chip sets the output duty-cycle
 179 based on the temperature of the associated thermal zone:
 180
 181                         Duty-Cycle      Duty-Cycle
 182         Temperature     Rising Temp     Falling Temp
 183         -----------     -----------     ------------
 184         full-speed      full-speed      full-speed
 185
 186                         < linearly adjusted duty-cycle >
 187
 188         low-speed       low-speed       low-speed
 189                         min-speed       low-speed
 190         min-speed       min-speed       min-speed
 191                         min-speed       min-speed
 192
 193
 194 Sysfs Attributes
 195 ----------------
 196
 197 Following is a list of all sysfs attributes that the driver provides, their
 198 permissions and a short description:
 199
 200 Name                            Perm    Description
 201 ----                            ----    -----------
 202 cpu0_vid                        RO      CPU core reference voltage in
 203                                         millivolts.
 204 vrm                             RW      Voltage regulator module version
 205                                         number.
 206
 207 in[0-6]_input                   RO      Measured voltage in millivolts.
 208 in[0-6]_min                     RW      Low limit for voltage input.
 209 in[0-6]_max                     RW      High limit for voltage input.
 210 in[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.
 213
 214 temp[1-3]_input                 RO      Measured temperature in millidegree
 215                                         Celsius.
 216 temp[1-3]_min                   RW      Low limit for temp input.
 217 temp[1-3]_max                   RW      High limit for temp input.
 218 temp[1-3]_offset                RW      Offset for temp input. This value will
 219                                         be added by the chip to the measured
 220                                         temperature.
 221 temp[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.
 224 temp[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.
 227
 228 zone[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
 234 zone[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.
 239 zone[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).
 244
 245 fan[1-6]_input                  RO      Measured fan speed in RPM.
 246 fan[1-6]_min                    RW      Low limit for fan input.
 247 fan[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.
 250 fan[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.
 254 fan[5-6]_max                    RW      Max attainable RPM at 100% duty-cycle.
 255                                         Required for chip to adjust the
 256                                         sampling rate accordingly.
 257
 258 pmw[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.
 262 pwm[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
 267 pwm[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.
 270 pmw[1-3,5-6]_freq               RW      Frequency of PWM output. Supported
 271                                         values are in the range 11Hz-30000Hz
 272                                         (default is 25000Hz).
 273 pmw[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).
 280 pwm[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]
 288 pwm[1-3]_auto_pwm_min           RW      Auto PWM min pwm. Minimum PWM duty-
 289                                         cycle. Supported values are 0 or
 290                                         auto_point1_pwm.
 291 pwm[1-3]_auto_point1_pwm        RW      Auto PWM pwm point. Auto_point1 is the
 292                                         low-speed duty-cycle.
 293 pwm[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).