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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
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parentInitial commit. (diff)
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Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
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+Kernel driver lm90
+==================
+
+Supported chips:
+
+ * National Semiconductor LM84
+
+ Prefix: 'lm84'
+
+ Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
+
+ Datasheet: Publicly available at the National Semiconductor website
+
+ * National Semiconductor LM90
+
+ Prefix: 'lm90'
+
+ Addresses scanned: I2C 0x4c
+
+ Datasheet: Publicly available at the National Semiconductor website
+
+ http://www.national.com/pf/LM/LM90.html
+
+ * National Semiconductor LM89
+
+ Prefix: 'lm89' (no auto-detection)
+
+ Addresses scanned: I2C 0x4c and 0x4d
+
+ Datasheet: Publicly available at the National Semiconductor website
+
+ http://www.national.com/mpf/LM/LM89.html
+
+ * National Semiconductor LM99
+
+ Prefix: 'lm99'
+
+ Addresses scanned: I2C 0x4c and 0x4d
+
+ Datasheet: Publicly available at the National Semiconductor website
+
+ http://www.national.com/pf/LM/LM99.html
+
+ * National Semiconductor LM86
+
+ Prefix: 'lm86'
+
+ Addresses scanned: I2C 0x4c
+
+ Datasheet: Publicly available at the National Semiconductor website
+
+ http://www.national.com/mpf/LM/LM86.html
+
+ * Analog Devices ADM1020
+
+ Prefix: 'adm1020'
+
+ Addresses scanned: I2C 0x4c - 0x4e
+
+ Datasheet: Publicly available at the Analog Devices website
+
+ * Analog Devices ADM1021
+
+ Prefix: 'adm1021'
+
+ Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
+
+ Datasheet: Publicly available at the Analog Devices website
+
+ * Analog Devices ADM1021A/ADM1023
+
+ Prefix: 'adm1023'
+
+ Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
+
+ Datasheet: Publicly available at the Analog Devices website
+
+ * Analog Devices ADM1032
+
+ Prefix: 'adm1032'
+
+ Addresses scanned: I2C 0x4c and 0x4d
+
+ Datasheet: Publicly available at the ON Semiconductor website
+
+ https://www.onsemi.com/PowerSolutions/product.do?id=ADM1032
+
+ * Analog Devices ADT7461
+
+ Prefix: 'adt7461'
+
+ Addresses scanned: I2C 0x4c and 0x4d
+
+ Datasheet: Publicly available at the ON Semiconductor website
+
+ https://www.onsemi.com/PowerSolutions/product.do?id=ADT7461
+
+ * Analog Devices ADT7461A
+
+ Prefix: 'adt7461a'
+
+ Addresses scanned: I2C 0x4c and 0x4d
+
+ Datasheet: Publicly available at the ON Semiconductor website
+
+ https://www.onsemi.com/PowerSolutions/product.do?id=ADT7461A
+
+ * Analog Devices ADT7481
+
+ Prefix: 'adt7481'
+
+ Addresses scanned: I2C 0x4b and 0x4c
+
+ Datasheet: Publicly available at the ON Semiconductor website
+
+ https://www.onsemi.com/PowerSolutions/product.do?id=ADT7481
+
+ * Analog Devices ADT7482
+
+ Prefix: 'adt7482'
+
+ Addresses scanned: I2C 0x4c
+
+ Datasheet: Publicly available at the ON Semiconductor website
+
+ https://www.onsemi.com/PowerSolutions/product.do?id=ADT7482
+
+ * Analog Devices ADT7483A
+
+ Prefix: 'adt7483a'
+
+ Addresses scanned: I2C 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b, 0x4c, 0x4d, 0x4e
+
+ Datasheet: Publicly available at the ON Semiconductor website
+
+ https://www.onsemi.com/PowerSolutions/product.do?id=ADT7483A
+
+ * ON Semiconductor NCT1008
+
+ Prefix: 'nct1008'
+
+ Addresses scanned: I2C 0x4c and 0x4d
+
+ Datasheet: Publicly available at the ON Semiconductor website
+
+ https://www.onsemi.com/PowerSolutions/product.do?id=NCT1008
+
+ * ON Semiconductor NCT210
+
+ Prefix: 'adm1021'
+
+ Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
+
+ Datasheet: Publicly available at the ON Semiconductor website
+
+ https://www.onsemi.com/PowerSolutions/product.do?id=NCT210
+
+ * ON Semiconductor NCT214
+
+ Prefix: 'nct214'
+
+ Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
+
+ Datasheet: Publicly available at the ON Semiconductor website
+
+ https://www.onsemi.com/PowerSolutions/product.do?id=NCT214
+
+ * ON Semiconductor NCT218
+
+ Prefix: 'nct218'
+
+ Addresses scanned: I2C 0x4c - 0x4d
+
+ Datasheet: Publicly available at the ON Semiconductor website
+
+ https://www.onsemi.com/PowerSolutions/product.do?id=NCT218
+
+ * ON Semiconductor NCT72
+
+ Prefix: 'nct72'
+
+ Addresses scanned: I2C 0x4c - 0x4d
+
+ Datasheet: Publicly available at the ON Semiconductor website
+
+ https://www.onsemi.com/PowerSolutions/product.do?id=NCT72
+
+ * Maxim MAX1617
+
+ Prefix: 'max1617'
+
+ Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
+
+ Datasheet: Publicly available at the Maxim website
+
+ * Maxim MAX1617A
+
+ Prefix: 'max1617a'
+
+ Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
+
+ Datasheet: Publicly available at the Maxim website
+
+ * Maxim MAX6642
+
+ Prefix: 'max6642'
+
+ Addresses scanned: I2C 0x48-0x4f
+
+ Datasheet: Publicly available at the Maxim website
+
+ http://datasheets.maxim-ic.com/en/ds/MAX6642.pdf
+
+ * Maxim MAX6646
+
+ Prefix: 'max6646'
+
+ Addresses scanned: I2C 0x4d
+
+ Datasheet: Publicly available at the Maxim website
+
+ http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3497
+
+ * Maxim MAX6647
+
+ Prefix: 'max6646'
+
+ Addresses scanned: I2C 0x4e
+
+ Datasheet: Publicly available at the Maxim website
+
+ http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3497
+
+ * Maxim MAX6648
+
+ Prefix: 'max6648'
+
+ Addresses scanned: I2C 0x4c
+
+ Datasheet: Publicly available at the Maxim website
+
+ http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3500
+
+ * Maxim MAX6649
+
+ Prefix: 'max6646'
+
+ Addresses scanned: I2C 0x4c
+
+ Datasheet: Publicly available at the Maxim website
+
+ http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3497
+
+ * Maxim MAX6654
+
+ Prefix: 'max6654'
+
+ Addresses scanned: I2C 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b,
+
+ 0x4c, 0x4d and 0x4e
+
+ Datasheet: Publicly available at the Maxim website
+
+ https://www.maximintegrated.com/en/products/sensors/MAX6654.html
+
+ * Maxim MAX6657
+
+ Prefix: 'max6657'
+
+ Addresses scanned: I2C 0x4c
+
+ Datasheet: Publicly available at the Maxim website
+
+ http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2578
+
+ * Maxim MAX6658
+
+ Prefix: 'max6657'
+
+ Addresses scanned: I2C 0x4c
+
+ Datasheet: Publicly available at the Maxim website
+
+ http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2578
+
+ * Maxim MAX6659
+
+ Prefix: 'max6659'
+
+ Addresses scanned: I2C 0x4c, 0x4d, 0x4e
+
+ Datasheet: Publicly available at the Maxim website
+
+ http://www.maxim-ic.com/quick_view2.cfm/qv_pk/2578
+
+ * Maxim MAX6680
+
+ Prefix: 'max6680'
+
+ Addresses scanned: I2C 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b,
+
+ 0x4c, 0x4d and 0x4e
+
+ Datasheet: Publicly available at the Maxim website
+
+ http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3370
+
+ * Maxim MAX6681
+
+ Prefix: 'max6680'
+
+ Addresses scanned: I2C 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b,
+
+ 0x4c, 0x4d and 0x4e
+
+ Datasheet: Publicly available at the Maxim website
+
+ http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3370
+
+ * Maxim MAX6692
+
+ Prefix: 'max6648'
+
+ Addresses scanned: I2C 0x4c
+
+ Datasheet: Publicly available at the Maxim website
+
+ http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3500
+
+ * Maxim MAX6695
+
+ Prefix: 'max6695'
+
+ Addresses scanned: I2C 0x18
+
+ Datasheet: Publicly available at the Maxim website
+
+ http://www.maxim-ic.com/datasheet/index.mvp/id/4199
+
+ * Maxim MAX6696
+
+ Prefix: 'max6695'
+
+ Addresses scanned: I2C 0x18, 0x19, 0x1a, 0x29, 0x2a, 0x2b,
+
+ 0x4c, 0x4d and 0x4e
+
+ Datasheet: Publicly available at the Maxim website
+
+ http://www.maxim-ic.com/datasheet/index.mvp/id/4199
+
+ * Winbond/Nuvoton W83L771W/G
+
+ Prefix: 'w83l771'
+
+ Addresses scanned: I2C 0x4c
+
+ Datasheet: No longer available
+
+ * Winbond/Nuvoton W83L771AWG/ASG
+
+ Prefix: 'w83l771'
+
+ Addresses scanned: I2C 0x4c
+
+ Datasheet: Not publicly available, can be requested from Nuvoton
+
+ * Philips/NXP SA56004X
+
+ Prefix: 'sa56004'
+
+ Addresses scanned: I2C 0x48 through 0x4F
+
+ Datasheet: Publicly available at NXP website
+
+ http://ics.nxp.com/products/interface/datasheet/sa56004x.pdf
+
+ * GMT G781
+
+ Prefix: 'g781'
+
+ Addresses scanned: I2C 0x4c, 0x4d
+
+ Datasheet: Not publicly available from GMT
+
+ * Texas Instruments TMP451
+
+ Prefix: 'tmp451'
+
+ Addresses scanned: I2C 0x4c
+
+ Datasheet: Publicly available at TI website
+
+ https://www.ti.com/litv/pdf/sbos686
+
+ * Texas Instruments TMP461
+
+ Prefix: 'tmp461'
+
+ Addresses scanned: I2C 0x48 through 0x4F
+
+ Datasheet: Publicly available at TI website
+
+ https://www.ti.com/lit/gpn/tmp461
+
+ * Philips NE1617, NE1617A
+
+ Prefix: 'max1617' (probably detected as a max1617)
+
+ Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
+
+ Datasheets: Publicly available at the Philips website
+
+ * Philips NE1618
+
+ Prefix: 'ne1618'
+
+ Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
+
+ Datasheets: Publicly available at the Philips website
+
+ * Genesys Logic GL523SM
+
+ Prefix: 'gl523sm'
+
+ Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
+
+ Datasheet:
+
+ * TI THMC10
+
+ Prefix: 'thmc10'
+
+ Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
+
+ Datasheet: Publicly available at the TI website
+
+ * Onsemi MC1066
+
+ Prefix: 'mc1066'
+
+ Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e
+
+ Datasheet: Publicly available at the Onsemi website
+
+Author: Jean Delvare <jdelvare@suse.de>
+
+
+Description
+-----------
+
+The LM90 is a digital temperature sensor. It senses its own temperature as
+well as the temperature of up to one external diode. It is compatible
+with many other devices, many of which are supported by this driver.
+
+The family of chips supported by this driver is derived from MAX1617.
+This chip as well as various compatible chips support a local and a remote
+temperature sensor with 8 bit accuracy. Later chips provide improved accuracy
+and other additional features such as hysteresis and temperature offset
+registers.
+
+Note that there is no easy way to differentiate between the MAX6657,
+MAX6658 and MAX6659 variants. The extra features of the MAX6659 are only
+supported by this driver if the chip is located at address 0x4d or 0x4e,
+or if the chip type is explicitly selected as max6659.
+The MAX6680 and MAX6681 only differ in their pinout, therefore they obviously
+can't (and don't need to) be distinguished.
+
+The different chipsets of the family are not strictly identical, although
+very similar. For reference, here comes a non-exhaustive list of specific
+features:
+
+LM84:
+ * 8 bit sensor resolution
+
+ADM1020, ADM1021, GL523SM, MAX1617, NE1617, NE1617A, THMC10:
+ * 8 bit sensor resolution
+ * Low temperature limits
+
+NCT210, NE1618:
+ * 11 bit sensor resolution for remote temperature sensor
+ * Low temperature limits
+
+ADM1021A, ADM1023:
+ * Temperature offset register for remote temperature sensor
+ * 11 bit resolution for remote temperature sensor
+ * Low temperature limits
+
+LM90:
+ * 11 bit resolution for remote temperature sensor
+ * Temperature offset register for remote temperature sensor
+ * Low and critical temperature limits
+ * Configurable conversion rate
+ * Filter and alert configuration register at 0xBF.
+ * ALERT is triggered by temperatures over critical limits.
+
+LM86 and LM89:
+ * Same as LM90
+ * Better external channel accuracy
+
+LM99:
+ * Same as LM89
+ * External temperature shifted by 16 degrees down
+
+ADM1032:
+ * Consecutive alert register at 0x22.
+ * Conversion averaging.
+ * Up to 64 conversions/s.
+ * ALERT is triggered by open remote sensor.
+ * SMBus PEC support for Write Byte and Receive Byte transactions.
+
+ADT7461, ADT7461A, NCT1008:
+ * Extended temperature range (breaks compatibility)
+ * Lower resolution for remote temperature
+ * SMBus PEC support for Write Byte and Receive Byte transactions.
+ * 10 bit temperature resolution
+
+ADT7481, ADT7482, ADT7483:
+ * Temperature offset register
+ * SMBus PEC support
+ * 10 bit temperature resolution for external sensors
+ * Two remote sensors
+ * Selectable address (ADT7483)
+
+MAX6642:
+ * No critical limit register
+ * Conversion rate not configurable
+ * Better local resolution (10 bit)
+ * 10 bit external sensor resolution
+
+MAX6646, MAX6647, MAX6649:
+ * Better local resolution
+ * Extended range unsigned external temperature
+
+MAX6648, MAX6692:
+ * Better local resolution
+ * Unsigned temperature
+
+MAX6654, MAX6690:
+ * Better local resolution
+ * Selectable address
+ * Remote sensor type selection
+ * Extended temperature range
+ * Extended resolution only available when conversion rate <= 1 Hz
+
+MAX6657 and MAX6658:
+ * Better local resolution
+ * Remote sensor type selection
+
+MAX6659:
+ * Better local resolution
+ * Selectable address
+ * Second critical temperature limit
+ * Remote sensor type selection
+
+MAX6680 and MAX6681:
+ * Selectable address
+ * Remote sensor type selection
+
+MAX6695 and MAX6696:
+ * Better local resolution
+ * Selectable address (max6696)
+ * Second critical temperature limit
+ * Two remote sensors
+
+W83L771W/G
+ * The G variant is lead-free, otherwise similar to the W.
+ * Filter and alert configuration register at 0xBF
+ * Moving average (depending on conversion rate)
+
+W83L771AWG/ASG
+ * Successor of the W83L771W/G, same features.
+ * The AWG and ASG variants only differ in package format.
+ * Diode ideality factor configuration (remote sensor) at 0xE3
+
+SA56004X:
+ * Better local resolution
+
+All temperature values are given in degrees Celsius. Resolution
+is 1.0 degree for the local temperature, 0.125 degree for the remote
+temperature, except for the MAX6654, MAX6657, MAX6658 and MAX6659 which have
+a resolution of 0.125 degree for both temperatures.
+
+Each sensor has its own high and low limits, plus a critical limit.
+Additionally, there is a relative hysteresis value common to both critical
+values. To make life easier to user-space applications, two absolute values
+are exported, one for each channel, but these values are of course linked.
+Only the local hysteresis can be set from user-space, and the same delta
+applies to the remote hysteresis.
+
+The lm90 driver will not update its values more frequently than configured with
+the update_interval attribute; reading them more often will do no harm, but will
+return 'old' values.
+
+SMBus Alert Support
+-------------------
+
+This driver has basic support for SMBus alert. When an alert is received,
+the status register is read and the faulty temperature channel is logged.
+
+The Analog Devices chips (ADM1032, ADT7461 and ADT7461A) and ON
+Semiconductor chips (NCT1008) do not implement the SMBus alert protocol
+properly so additional care is needed: the ALERT output is disabled when
+an alert is received, and is re-enabled only when the alarm is gone.
+Otherwise the chip would block alerts from other chips in the bus as long
+as the alarm is active.
+
+PEC Support
+-----------
+
+The ADM1032 is the only chip of the family which supports PEC. It does
+not support PEC on all transactions though, so some care must be taken.
+
+When reading a register value, the PEC byte is computed and sent by the
+ADM1032 chip. However, in the case of a combined transaction (SMBus Read
+Byte), the ADM1032 computes the CRC value over only the second half of
+the message rather than its entirety, because it thinks the first half
+of the message belongs to a different transaction. As a result, the CRC
+value differs from what the SMBus master expects, and all reads fail.
+
+For this reason, the lm90 driver will enable PEC for the ADM1032 only if
+the bus supports the SMBus Send Byte and Receive Byte transaction types.
+These transactions will be used to read register values, instead of
+SMBus Read Byte, and PEC will work properly.
+
+Additionally, the ADM1032 doesn't support SMBus Send Byte with PEC.
+Instead, it will try to write the PEC value to the register (because the
+SMBus Send Byte transaction with PEC is similar to a Write Byte transaction
+without PEC), which is not what we want. Thus, PEC is explicitly disabled
+on SMBus Send Byte transactions in the lm90 driver.
+
+PEC on byte data transactions represents a significant increase in bandwidth
+usage (+33% for writes, +25% for reads) in normal conditions. With the need
+to use two SMBus transaction for reads, this overhead jumps to +50%. Worse,
+two transactions will typically mean twice as much delay waiting for
+transaction completion, effectively doubling the register cache refresh time.
+I guess reliability comes at a price, but it's quite expensive this time.
+
+So, as not everyone might enjoy the slowdown, PEC is disabled by default and
+can be enabled through sysfs. Just write 1 to the "pec" file and PEC will be
+enabled. Write 0 to that file to disable PEC again.