^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) Kernel driver adt7475
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) =====================
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) Supported chips:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) * Analog Devices ADT7473
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) Prefix: 'adt7473'
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) Addresses scanned: I2C 0x2C, 0x2D, 0x2E
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) Datasheet: Publicly available at the On Semiconductors website
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) * Analog Devices ADT7475
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) Prefix: 'adt7475'
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) Addresses scanned: I2C 0x2E
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) Datasheet: Publicly available at the On Semiconductors website
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) * Analog Devices ADT7476
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) Prefix: 'adt7476'
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) Addresses scanned: I2C 0x2C, 0x2D, 0x2E
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) Datasheet: Publicly available at the On Semiconductors website
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) * Analog Devices ADT7490
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) Prefix: 'adt7490'
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) Addresses scanned: I2C 0x2C, 0x2D, 0x2E
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) Datasheet: Publicly available at the On Semiconductors website
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) Authors:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) - Jordan Crouse
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) - Hans de Goede
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) - Darrick J. Wong (documentation)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) - Jean Delvare
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) Description
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) -----------
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) This driver implements support for the Analog Devices ADT7473, ADT7475,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) ADT7476 and ADT7490 chip family. The ADT7473 and ADT7475 differ only in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) minor details. The ADT7476 has additional features, including extra voltage
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) measurement inputs and VID support. The ADT7490 also has additional
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) features, including extra voltage measurement inputs and PECI support. All
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) the supported chips will be collectively designed by the name "ADT747x" in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) the rest of this document.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) The ADT747x uses the 2-wire interface compatible with the SMBus 2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) specification. Using an analog to digital converter it measures three (3)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) temperatures and two (2) or more voltages. It has four (4) 16-bit counters
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) for measuring fan speed. There are three (3) PWM outputs that can be used
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) to control fan speed.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) A sophisticated control system for the PWM outputs is designed into the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) ADT747x that allows fan speed to be adjusted automatically based on any of the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) three temperature sensors. Each PWM output is individually adjustable and
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) programmable. Once configured, the ADT747x will adjust the PWM outputs in
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) response to the measured temperatures without further host intervention.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) This feature can also be disabled for manual control of the PWM's.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) Each of the measured inputs (voltage, temperature, fan speed) has
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) corresponding high/low limit values. The ADT747x will signal an ALARM if
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) any measured value exceeds either limit.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) The ADT747x samples all inputs continuously. The driver will not read
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) the registers more often than once every other second. Further,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) configuration data is only read once per minute.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) Chip Differences Summary
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) ------------------------
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) ADT7473:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) * 2 voltage inputs
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) * system acoustics optimizations (not implemented)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) ADT7475:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) * 2 voltage inputs
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) ADT7476:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) * 5 voltage inputs
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) * VID support
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) ADT7490:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) * 6 voltage inputs
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) * 1 Imon input (not implemented)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) * PECI support (not implemented)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) * 2 GPIO pins (not implemented)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) * system acoustics optimizations (not implemented)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) Sysfs Mapping
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) -------------
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) ==== =========== =========== ========= ==========
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) in ADT7490 ADT7476 ADT7475 ADT7473
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) ==== =========== =========== ========= ==========
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) in0 2.5VIN (22) 2.5VIN (22) - -
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) in1 VCCP (23) VCCP (23) VCCP (14) VCCP (14)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) in2 VCC (4) VCC (4) VCC (4) VCC (3)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) in3 5VIN (20) 5VIN (20)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) in4 12VIN (21) 12VIN (21)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) in5 VTT (8)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) ==== =========== =========== ========= ==========
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) Special Features
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) ----------------
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) The ADT747x has a 10-bit ADC and can therefore measure temperatures
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) with a resolution of 0.25 degree Celsius. Temperature readings can be
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) configured either for two's complement format or "Offset 64" format,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) wherein 64 is subtracted from the raw value to get the temperature value.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) The datasheet is very detailed and describes a procedure for determining
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) an optimal configuration for the automatic PWM control.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) Fan Speed Control
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) -----------------
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) The driver exposes two trip points per PWM channel.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128) - point1: Set the PWM speed at the lower temperature bound
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) - point2: Set the PWM speed at the higher temperature bound
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) The ADT747x will scale the PWM linearly between the lower and higher PWM
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) speed when the temperature is between the two temperature boundaries.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) Temperature boundaries are associated to temperature channels rather than
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) PWM outputs, and a given PWM output can be controlled by several temperature
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) channels. As a result, the ADT747x may compute more than one PWM value
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) for a channel at a given time, in which case the maximum value (fastest
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137) fan speed) is applied. PWM values range from 0 (off) to 255 (full speed).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) Fan speed may be set to maximum when the temperature sensor associated with
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140) the PWM control exceeds temp#_max.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) At Tmin - hysteresis the PWM output can either be off (0% duty cycle) or at the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143) minimum (i.e. auto_point1_pwm). This behaviour can be configured using the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) `pwm[1-*]_stall_disable sysfs attribute`. A value of 0 means the fans will shut
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) off. A value of 1 means the fans will run at auto_point1_pwm.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) The responsiveness of the ADT747x to temperature changes can be configured.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) This allows smoothing of the fan speed transition. To set the transition time
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149) set the value in ms in the `temp[1-*]_smoothing` sysfs attribute.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) Notes
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) -----
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) The nVidia binary driver presents an ADT7473 chip via an on-card i2c bus.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) Unfortunately, they fail to set the i2c adapter class, so this driver may
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) fail to find the chip until the nvidia driver is patched.
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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