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: 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
  21
  22 Authors:
  23     Juerg Haefliger <juergh@gmail.com>
  24
  25
  26 Module Parameters
  27 -----------------
  28
  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
  37
  38
  39 Description
  40 -----------
  41
  42 This driver implements support for the hardware monitoring capabilities of the
  43 SMSC DME1737 and Asus A8000 (which are the same), SMSC SCH5027, SCH311x,
  44 and SCH5127 Super-I/O chips. These chips feature monitoring of 3 temp sensors
  45 temp[1-3] (2 remote diodes and 1 internal), 7 voltages in[0-6] (6 external and
  46 1 internal) and up to 6 fan speeds fan[1-6]. Additionally, the chips implement
  47 up to 5 PWM outputs pwm[1-3,5-6] for controlling fan speeds both manually and
  48 automatically.
  49
  50 For the DME1737, A8000 and SCH5027, fan[1-2] and pwm[1-2] are always present.
  51 Fan[3-6] and pwm[3,5-6] are optional features and their availability depends on
  52 the configuration of the chip. The driver will detect which features are
  53 present during initialization and create the sysfs attributes accordingly.
  54
  55 For the SCH311x and SCH5127, fan[1-3] and pwm[1-3] are always present and
  56 fan[4-6] and pwm[5-6] don't exist.
  57
  58 The hardware monitoring features of the DME1737, A8000, and SCH5027 are only
  59 accessible via SMBus, while the SCH311x and SCH5127 only provide access via
  60 the ISA bus. The driver will therefore register itself as an I2C client driver
  61 if it detects a DME1737, A8000, or SCH5027 and as a platform driver if it
  62 detects a SCH311x or SCH5127 chip.
  63
  64
  65 Voltage Monitoring
  66 ------------------
  67
  68 The voltage inputs are sampled with 12-bit resolution and have internal
  69 scaling resistors. The values returned by the driver therefore reflect true
  70 millivolts and don't need scaling. The voltage inputs are mapped as follows
  71 (the last column indicates the input ranges):
  72
  73 DME1737, 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
  81
  82 SCH311x:
  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
  90
  91 SCH5027:
  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
  99
 100 SCH5127:
 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
 108
 109 Each voltage input has associated min and max limits which trigger an alarm
 110 when crossed.
 111
 112
 113 Temperature Monitoring
 114 ----------------------
 115
 116 Temperatures are measured with 12-bit resolution and reported in millidegree
 117 Celsius. The chip also features offsets for all 3 temperature inputs which -
 118 when programmed - get added to the input readings. The chip does all the
 119 scaling by itself and the driver therefore reports true temperatures that don't
 120 need any user-space adjustments. The temperature inputs are mapped as follows
 121 (the last column indicates the input ranges):
 122
 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
 126
 127 Each temperature input has associated min and max limits which trigger an alarm
 128 when crossed. Additionally, each temperature input has a fault attribute that
 129 returns 1 when a faulty diode or an unconnected input is detected and 0
 130 otherwise.
 131
 132
 133 Fan Monitoring
 134 --------------
 135
 136 Fan RPMs are measured with 16-bit resolution. The chip provides inputs for 6
 137 fan tachometers. All 6 inputs have an associated min limit which triggers an
 138 alarm when crossed. Fan inputs 1-4 provide type attributes that need to be set
 139 to the number of pulses per fan revolution that the connected tachometer
 140 generates. Supported values are 1, 2, and 4. Fan inputs 5-6 only support fans
 141 that generate 2 pulses per revolution. Fan inputs 5-6 also provide a max
 142 attribute that needs to be set to the maximum attainable RPM (fan at 100% duty-
 143 cycle) of the input. The chip adjusts the sampling rate based on this value.
 144
 145
 146 PWM Output Control
 147 ------------------
 148
 149 This chip features 5 PWM outputs. PWM outputs 1-3 are associated with fan
 150 inputs 1-3 and PWM outputs 5-6 are associated with fan inputs 5-6. PWM outputs
 151 1-3 can be configured to operate either in manual or automatic mode by setting
 152 the appropriate enable attribute accordingly. PWM outputs 5-6 can only operate
 153 in manual mode, their enable attributes are therefore read-only. When set to
 154 manual mode, the fan speed is set by writing the duty-cycle value to the
 155 appropriate PWM attribute. In automatic mode, the PWM attribute returns the
 156 current duty-cycle as set by the fan controller in the chip. All PWM outputs
 157 support the setting of the output frequency via the freq attribute.
 158
 159 In automatic mode, the chip supports the setting of the PWM ramp rate which
 160 defines how fast the PWM output is adjusting to changes of the associated
 161 temperature input. Associating PWM outputs to temperature inputs is done via
 162 temperature zones. The chip features 3 zones whose assignments to temperature
 163 inputs is static and determined during initialization. These assignments can
 164 be retrieved via the zone[1-3]_auto_channels_temp attributes. Each PWM output
 165 is assigned to one (or hottest of multiple) temperature zone(s) through the
 166 pwm[1-3]_auto_channels_zone attributes. Each PWM output has 3 distinct output
 167 duty-cycles: full, low, and min. Full is internally hard-wired to 255 (100%)
 168 and low and min can be programmed via pwm[1-3]_auto_point1_pwm and
 169 pwm[1-3]_auto_pwm_min, respectively. The thermal thresholds of the zones are
 170 programmed via zone[1-3]_auto_point[1-3]_temp and
 171 zone[1-3]_auto_point1_temp_hyst:
 172
 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
 176
 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
 181
 182 The chip adjusts the output duty-cycle linearly in the range of auto_point1_pwm
 183 to auto_point2_pwm if the temperature of the associated zone is between
 184 auto_point1_temp and auto_point2_temp. If the temperature drops below the
 185 auto_point1_temp_hyst value, the output duty-cycle is set to the auto_pwm_min
 186 value which only supports two values: 0 or auto_point1_pwm. That means that the
 187 fan either turns completely off or keeps spinning with the low-speed
 188 duty-cycle. If any of the temperatures rise above the auto_point3_temp value,
 189 all PWM outputs are set to 100% duty-cycle.
 190
 191 Following is another representation of how the chip sets the output duty-cycle
 192 based on the temperature of the associated thermal zone:
 193
 194                         Duty-Cycle      Duty-Cycle
 195         Temperature     Rising Temp     Falling Temp
 196         -----------     -----------     ------------
 197         full-speed      full-speed      full-speed
 198
 199                         < linearly adjusted duty-cycle >
 200
 201         low-speed       low-speed       low-speed
 202                         min-speed       low-speed
 203         min-speed       min-speed       min-speed
 204                         min-speed       min-speed
 205
 206
 207 Sysfs Attributes
 208 ----------------
 209
 210 Following is a list of all sysfs attributes that the driver provides, their
 211 permissions and a short description:
 212
 213 Name                            Perm    Description
 214 ----                            ----    -----------
 215 cpu0_vid                        RO      CPU core reference voltage in
 216                                         millivolts.
 217 vrm                             RW      Voltage regulator module version
 218                                         number.
 219
 220 in[0-6]_input                   RO      Measured voltage in millivolts.
 221 in[0-6]_min                     RW      Low limit for voltage input.
 222 in[0-6]_max                     RW      High limit for voltage input.
 223 in[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.
 226
 227 temp[1-3]_input                 RO      Measured temperature in millidegree
 228                                         Celsius.
 229 temp[1-3]_min                   RW      Low limit for temp input.
 230 temp[1-3]_max                   RW      High limit for temp input.
 231 temp[1-3]_offset                RW      Offset for temp input. This value will
 232                                         be added by the chip to the measured
 233                                         temperature.
 234 temp[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.
 237 temp[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.
 240
 241 zone[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
 247 zone[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.
 252 zone[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).
 257
 258 fan[1-6]_input                  RO      Measured fan speed in RPM.
 259 fan[1-6]_min                    RW      Low limit for fan input.
 260 fan[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.
 263 fan[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.
 267 fan[5-6]_max                    RW      Max attainable RPM at 100% duty-cycle.
 268                                         Required for chip to adjust the
 269                                         sampling rate accordingly.
 270
 271 pmw[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.
 275 pwm[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
 280 pwm[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.
 283 pmw[1-3,5-6]_freq               RW      Frequency of PWM output. Supported
 284                                         values are in the range 11Hz-30000Hz
 285                                         (default is 25000Hz).
 286 pmw[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).
 293 pwm[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]
 301 pwm[1-3]_auto_pwm_min           RW      Auto PWM min pwm. Minimum PWM duty-
 302                                         cycle. Supported values are 0 or
 303                                         auto_point1_pwm.
 304 pwm[1-3]_auto_point1_pwm        RW      Auto PWM pwm point. Auto_point1 is the
 305                                         low-speed duty-cycle.
 306 pwm[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).
 309
 310 Chip Differences
 311 ----------------
 312
 313 Feature                 dme1737 sch311x sch5027 sch5127
 314 -------------------------------------------------------
 315 temp[1-3]_offset        yes     yes
 316 vid                     yes
 317 zone3                   yes     yes     yes
 318 zone[1-3]_hyst          yes     yes
 319 pwm min/off             yes     yes
 320 fan3                    opt     yes     opt     yes
 321 pwm3                    opt     yes     opt     yes
 322 fan4                    opt             opt
 323 fan5                    opt             opt
 324 pwm5                    opt             opt
 325 fan6                    opt             opt
 326 pwm6                    opt             opt