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diff --git a/Documentation/hwmon/dme1737 b/Documentation/hwmon/dme1737 new file mode 100644 index 0000000..1a0f3d6 --- /dev/null +++ b/Documentation/hwmon/dme1737 @@ -0,0 +1,257 @@ +Kernel driver dme1737 +===================== + +Supported chips: + * SMSC DME1737 and compatibles (like Asus A8000) + Prefix: 'dme1737' + Addresses scanned: I2C 0x2c, 0x2d, 0x2e + Datasheet: Provided by SMSC upon request and under NDA + +Authors: + Juerg Haefliger <juergh@gmail.com> + + +Module Parameters +----------------- + +* force_start: bool Enables the monitoring of voltage, fan and temp inputs + and PWM output control functions. Using this parameter + shouldn't be required since the BIOS usually takes care + of this. + +Note that there is no need to use this parameter if the driver loads without +complaining. The driver will say so if it is necessary. + + +Description +----------- + +This driver implements support for the hardware monitoring capabilities of the +SMSC DME1737 and Asus A8000 (which are the same) Super-I/O chips. This chip +features monitoring of 3 temp sensors temp[1-3] (2 remote diodes and 1 +internal), 7 voltages in[0-6] (6 external and 1 internal) and 6 fan speeds +fan[1-6]. Additionally, the chip implements 5 PWM outputs pwm[1-3,5-6] for +controlling fan speeds both manually and automatically. + +Fan[3-6] and pwm[3,5-6] are optional features and their availability is +dependent on the configuration of the chip. The driver will detect which +features are present during initialization and create the sysfs attributes +accordingly. + + +Voltage Monitoring +------------------ + +The voltage inputs are sampled with 12-bit resolution and have internal +scaling resistors. The values returned by the driver therefore reflect true +millivolts and don't need scaling. The voltage inputs are mapped as follows +(the last column indicates the input ranges): + + in0: +5VTR (+5V standby) 0V - 6.64V + in1: Vccp (processor core) 0V - 3V + in2: VCC (internal +3.3V) 0V - 4.38V + in3: +5V 0V - 6.64V + in4: +12V 0V - 16V + in5: VTR (+3.3V standby) 0V - 4.38V + in6: Vbat (+3.0V) 0V - 4.38V + +Each voltage input has associated min and max limits which trigger an alarm +when crossed. + + +Temperature Monitoring +---------------------- + +Temperatures are measured with 12-bit resolution and reported in millidegree +Celsius. The chip also features offsets for all 3 temperature inputs which - +when programmed - get added to the input readings. The chip does all the +scaling by itself and the driver therefore reports true temperatures that don't +need any user-space adjustments. The temperature inputs are mapped as follows +(the last column indicates the input ranges): + + temp1: Remote diode 1 (3904 type) temperature -127C - +127C + temp2: DME1737 internal temperature -127C - +127C + temp3: Remote diode 2 (3904 type) temperature -127C - +127C + +Each temperature input has associated min and max limits which trigger an alarm +when crossed. Additionally, each temperature input has a fault attribute that +returns 1 when a faulty diode or an unconnected input is detected and 0 +otherwise. + + +Fan Monitoring +-------------- + +Fan RPMs are measured with 16-bit resolution. The chip provides inputs for 6 +fan tachometers. All 6 inputs have an associated min limit which triggers an +alarm when crossed. Fan inputs 1-4 provide type attributes that need to be set +to the number of pulses per fan revolution that the connected tachometer +generates. Supported values are 1, 2, and 4. Fan inputs 5-6 only support fans +that generate 2 pulses per revolution. Fan inputs 5-6 also provide a max +attribute that needs to be set to the maximum attainable RPM (fan at 100% duty- +cycle) of the input. The chip adjusts the sampling rate based on this value. + + +PWM Output Control +------------------ + +This chip features 5 PWM outputs. PWM outputs 1-3 are associated with fan +inputs 1-3 and PWM outputs 5-6 are associated with fan inputs 5-6. PWM outputs +1-3 can be configured to operate either in manual or automatic mode by setting +the appropriate enable attribute accordingly. PWM outputs 5-6 can only operate +in manual mode, their enable attributes are therefore read-only. When set to +manual mode, the fan speed is set by writing the duty-cycle value to the +appropriate PWM attribute. In automatic mode, the PWM attribute returns the +current duty-cycle as set by the fan controller in the chip. All PWM outputs +support the setting of the output frequency via the freq attribute. + +In automatic mode, the chip supports the setting of the PWM ramp rate which +defines how fast the PWM output is adjusting to changes of the associated +temperature input. Associating PWM outputs to temperature inputs is done via +temperature zones. The chip features 3 zones whose assignments to temperature +inputs is static and determined during initialization. These assignments can +be retrieved via the zone[1-3]_auto_channels_temp attributes. Each PWM output +is assigned to one (or hottest of multiple) temperature zone(s) through the +pwm[1-3]_auto_channels_zone attributes. Each PWM output has 3 distinct output +duty-cycles: full, low, and min. Full is internally hard-wired to 255 (100%) +and low and min can be programmed via pwm[1-3]_auto_point1_pwm and +pwm[1-3]_auto_pwm_min, respectively. The thermal thresholds of the zones are +programmed via zone[1-3]_auto_point[1-3]_temp and +zone[1-3]_auto_point1_temp_hyst: + + pwm[1-3]_auto_point2_pwm full-speed duty-cycle (255, i.e., 100%) + pwm[1-3]_auto_point1_pwm low-speed duty-cycle + pwm[1-3]_auto_pwm_min min-speed duty-cycle + + zone[1-3]_auto_point3_temp full-speed temp (all outputs) + zone[1-3]_auto_point2_temp full-speed temp + zone[1-3]_auto_point1_temp low-speed temp + zone[1-3]_auto_point1_temp_hyst min-speed temp + +The chip adjusts the output duty-cycle linearly in the range of auto_point1_pwm +to auto_point2_pwm if the temperature of the associated zone is between +auto_point1_temp and auto_point2_temp. If the temperature drops below the +auto_point1_temp_hyst value, the output duty-cycle is set to the auto_pwm_min +value which only supports two values: 0 or auto_point1_pwm. That means that the +fan either turns completely off or keeps spinning with the low-speed +duty-cycle. If any of the temperatures rise above the auto_point3_temp value, +all PWM outputs are set to 100% duty-cycle. + +Following is another representation of how the chip sets the output duty-cycle +based on the temperature of the associated thermal zone: + + Duty-Cycle Duty-Cycle + Temperature Rising Temp Falling Temp + ----------- ----------- ------------ + full-speed full-speed full-speed + + < linearly adjusted duty-cycle > + + low-speed low-speed low-speed + min-speed low-speed + min-speed min-speed min-speed + min-speed min-speed + + +Sysfs Attributes +---------------- + +Following is a list of all sysfs attributes that the driver provides, their +permissions and a short description: + +Name Perm Description +---- ---- ----------- +cpu0_vid RO CPU core reference voltage in + millivolts. +vrm RW Voltage regulator module version + number. + +in[0-6]_input RO Measured voltage in millivolts. +in[0-6]_min RW Low limit for voltage input. +in[0-6]_max RW High limit for voltage input. +in[0-6]_alarm RO Voltage input alarm. Returns 1 if + voltage input is or went outside the + associated min-max range, 0 otherwise. + +temp[1-3]_input RO Measured temperature in millidegree + Celsius. +temp[1-3]_min RW Low limit for temp input. +temp[1-3]_max RW High limit for temp input. +temp[1-3]_offset RW Offset for temp input. This value will + be added by the chip to the measured + temperature. +temp[1-3]_alarm RO Alarm for temp input. Returns 1 if temp + input is or went outside the associated + min-max range, 0 otherwise. +temp[1-3]_fault RO Temp input fault. Returns 1 if the chip + detects a faulty thermal diode or an + unconnected temp input, 0 otherwise. + +zone[1-3]_auto_channels_temp RO Temperature zone to temperature input + mapping. This attribute is a bitfield + and supports the following values: + 1: temp1 + 2: temp2 + 4: temp3 +zone[1-3]_auto_point1_temp_hyst RW Auto PWM temp point1 hysteresis. The + output of the corresponding PWM is set + to the pwm_auto_min value if the temp + falls below the auto_point1_temp_hyst + value. +zone[1-3]_auto_point[1-3]_temp RW Auto PWM temp points. Auto_point1 is + the low-speed temp, auto_point2 is the + full-speed temp, and auto_point3 is the + temp at which all PWM outputs are set + to full-speed (100% duty-cycle). + +fan[1-6]_input RO Measured fan speed in RPM. +fan[1-6]_min RW Low limit for fan input. +fan[1-6]_alarm RO Alarm for fan input. Returns 1 if fan + input is or went below the associated + min value, 0 otherwise. +fan[1-4]_type RW Type of attached fan. Expressed in + number of pulses per revolution that + the fan generates. Supported values are + 1, 2, and 4. +fan[5-6]_max RW Max attainable RPM at 100% duty-cycle. + Required for chip to adjust the + sampling rate accordingly. + +pmw[1-3,5-6] RO/RW Duty-cycle of PWM output. Supported + values are 0-255 (0%-100%). Only + writeable if the associated PWM is in + manual mode. +pwm[1-3]_enable RW Enable of PWM outputs 1-3. Supported + values are: + 0: turned off (output @ 100%) + 1: manual mode + 2: automatic mode +pwm[5-6]_enable RO Enable of PWM outputs 5-6. Always + returns 1 since these 2 outputs are + hard-wired to manual mode. +pmw[1-3,5-6]_freq RW Frequency of PWM output. Supported + values are in the range 11Hz-30000Hz + (default is 25000Hz). +pmw[1-3]_ramp_rate RW Ramp rate of PWM output. Determines how + fast the PWM duty-cycle will change + when the PWM is in automatic mode. + Expressed in ms per PWM step. Supported + values are in the range 0ms-206ms + (default is 0, which means the duty- + cycle changes instantly). +pwm[1-3]_auto_channels_zone RW PWM output to temperature zone mapping. + This attribute is a bitfield and + supports the following values: + 1: zone1 + 2: zone2 + 4: zone3 + 6: highest of zone[2-3] + 7: highest of zone[1-3] +pwm[1-3]_auto_pwm_min RW Auto PWM min pwm. Minimum PWM duty- + cycle. Supported values are 0 or + auto_point1_pwm. +pwm[1-3]_auto_point1_pwm RW Auto PWM pwm point. Auto_point1 is the + low-speed duty-cycle. +pwm[1-3]_auto_point2_pwm RO Auto PWM pwm point. Auto_point2 is the + full-speed duty-cycle which is hard- + wired to 255 (100% duty-cycle). |
