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diff --git a/Documentation/hwmon/adt7475 b/Documentation/hwmon/adt7475 deleted file mode 100644 index 01b46b290532..000000000000 --- a/Documentation/hwmon/adt7475 +++ /dev/null @@ -1,138 +0,0 @@ -Kernel driver adt7475 -===================== - -Supported chips: - * Analog Devices ADT7473 - Prefix: 'adt7473' - Addresses scanned: I2C 0x2C, 0x2D, 0x2E - Datasheet: Publicly available at the On Semiconductors website - * Analog Devices ADT7475 - Prefix: 'adt7475' - Addresses scanned: I2C 0x2E - Datasheet: Publicly available at the On Semiconductors website - * Analog Devices ADT7476 - Prefix: 'adt7476' - Addresses scanned: I2C 0x2C, 0x2D, 0x2E - Datasheet: Publicly available at the On Semiconductors website - * Analog Devices ADT7490 - Prefix: 'adt7490' - Addresses scanned: I2C 0x2C, 0x2D, 0x2E - Datasheet: Publicly available at the On Semiconductors website - -Authors: - Jordan Crouse - Hans de Goede - Darrick J. Wong (documentation) - Jean Delvare - - -Description ------------ - -This driver implements support for the Analog Devices ADT7473, ADT7475, -ADT7476 and ADT7490 chip family. The ADT7473 and ADT7475 differ only in -minor details. The ADT7476 has additional features, including extra voltage -measurement inputs and VID support. The ADT7490 also has additional -features, including extra voltage measurement inputs and PECI support. All -the supported chips will be collectively designed by the name "ADT747x" in -the rest of this document. - -The ADT747x uses the 2-wire interface compatible with the SMBus 2.0 -specification. Using an analog to digital converter it measures three (3) -temperatures and two (2) or more voltages. It has four (4) 16-bit counters -for measuring fan speed. There are three (3) PWM outputs that can be used -to control fan speed. - -A sophisticated control system for the PWM outputs is designed into the -ADT747x that allows fan speed to be adjusted automatically based on any of the -three temperature sensors. Each PWM output is individually adjustable and -programmable. Once configured, the ADT747x will adjust the PWM outputs in -response to the measured temperatures without further host intervention. -This feature can also be disabled for manual control of the PWM's. - -Each of the measured inputs (voltage, temperature, fan speed) has -corresponding high/low limit values. The ADT747x will signal an ALARM if -any measured value exceeds either limit. - -The ADT747x samples all inputs continuously. The driver will not read -the registers more often than once every other second. Further, -configuration data is only read once per minute. - -Chip Differences Summary ------------------------- - -ADT7473: - * 2 voltage inputs - * system acoustics optimizations (not implemented) - -ADT7475: - * 2 voltage inputs - -ADT7476: - * 5 voltage inputs - * VID support - -ADT7490: - * 6 voltage inputs - * 1 Imon input (not implemented) - * PECI support (not implemented) - * 2 GPIO pins (not implemented) - * system acoustics optimizations (not implemented) - -Sysfs Mapping -------------- - - ADT7490 ADT7476 ADT7475 ADT7473 - ------- ------- ------- ------- -in0 2.5VIN (22) 2.5VIN (22) - - -in1 VCCP (23) VCCP (23) VCCP (14) VCCP (14) -in2 VCC (4) VCC (4) VCC (4) VCC (3) -in3 5VIN (20) 5VIN (20) -in4 12VIN (21) 12VIN (21) -in5 VTT (8) - -Special Features ----------------- - -The ADT747x has a 10-bit ADC and can therefore measure temperatures -with a resolution of 0.25 degree Celsius. Temperature readings can be -configured either for two's complement format or "Offset 64" format, -wherein 64 is subtracted from the raw value to get the temperature value. - -The datasheet is very detailed and describes a procedure for determining -an optimal configuration for the automatic PWM control. - -Fan Speed Control ------------------ - -The driver exposes two trip points per PWM channel. - -point1: Set the PWM speed at the lower temperature bound -point2: Set the PWM speed at the higher temperature bound - -The ADT747x will scale the PWM linearly between the lower and higher PWM -speed when the temperature is between the two temperature boundaries. -Temperature boundaries are associated to temperature channels rather than -PWM outputs, and a given PWM output can be controlled by several temperature -channels. As a result, the ADT747x may compute more than one PWM value -for a channel at a given time, in which case the maximum value (fastest -fan speed) is applied. PWM values range from 0 (off) to 255 (full speed). - -Fan speed may be set to maximum when the temperature sensor associated with -the PWM control exceeds temp#_max. - -At Tmin - hysteresis the PWM output can either be off (0% duty cycle) or at the -minimum (i.e. auto_point1_pwm). This behaviour can be configured using the -pwm[1-*]_stall_disable sysfs attribute. A value of 0 means the fans will shut -off. A value of 1 means the fans will run at auto_point1_pwm. - -The responsiveness of the ADT747x to temperature changes can be configured. -This allows smoothing of the fan speed transition. To set the transition time -set the value in ms in the temp[1-*]_smoothing sysfs attribute. - -Notes ------ - -The nVidia binary driver presents an ADT7473 chip via an on-card i2c bus. -Unfortunately, they fail to set the i2c adapter class, so this driver may -fail to find the chip until the nvidia driver is patched. |