Datasheet: Publicly available at the National Semiconductor website
http://www.national.com/pf/LM/LM90.html
* National Semiconductor LM89
- Prefix: 'lm99'
+ Prefix: 'lm89' (no auto-detection)
Addresses scanned: I2C 0x4c and 0x4d
Datasheet: Publicly available at the National Semiconductor website
- http://www.national.com/pf/LM/LM89.html
+ http://www.national.com/mpf/LM/LM89.html
* National Semiconductor LM99
Prefix: 'lm99'
Addresses scanned: I2C 0x4c and 0x4d
Prefix: 'lm86'
Addresses scanned: I2C 0x4c
Datasheet: Publicly available at the National Semiconductor website
- http://www.national.com/pf/LM/LM86.html
+ http://www.national.com/mpf/LM/LM86.html
* Analog Devices ADM1032
Prefix: 'adm1032'
- Addresses scanned: I2C 0x4c
- Datasheet: Publicly available at the Analog Devices website
- http://products.analog.com/products/info.asp?product=ADM1032
+ Addresses scanned: I2C 0x4c and 0x4d
+ Datasheet: Publicly available at the ON Semiconductor website
+ http://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
+ http://www.onsemi.com/PowerSolutions/product.do?id=ADT7461
+ * 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: 'max6646'
Addresses scanned: I2C 0x4c
- Datasheet: Publicly available at the Analog Devices website
- http://products.analog.com/products/info.asp?product=ADT7461
- Note: Only if in ADM1032 compatibility mode
+ 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 MAX6657
Prefix: 'max6657'
Addresses scanned: I2C 0x4c
Addresses scanned: I2C 0x4c, 0x4d (unsupported 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: 'max6646'
+ Addresses scanned: I2C 0x4c
+ Datasheet: Publicly available at the Maxim website
+ http://www.maxim-ic.com/quick_view2.cfm/qv_pk/3500
+ * Winbond/Nuvoton W83L771AWG/ASG
+ Prefix: 'w83l771'
+ Addresses scanned: I2C 0x4c
+ Datasheet: Not publicly available, can be requested from Nuvoton
Author: Jean Delvare <khali@linux-fr.org>
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 such as the LM86, the LM89, the LM99, the ADM1032,
-the MAX6657, MAX6658 and the MAX6659 all of which are supported by this driver.
-Note that there is no easy way to differentiate between the last three
-variants. The extra address and features of the MAX6659 are not supported by
-this driver. Additionally, the ADT7461 is supported if found in ADM1032
-compatibility mode.
+with many other devices, many of which are supported by this driver.
+
+Note that there is no easy way to differentiate between the MAX6657,
+MAX6658 and MAX6659 variants. The extra address and features of the
+MAX6659 are not supported by this driver. The MAX6680 and MAX6681 only
+differ in their pinout, therefore they obviously can't (and don't need to)
+be distinguished.
The specificity of this family of chipsets over the ADM1021/LM84
family is that it features critical limits with hysteresis, and an
increased resolution of the remote temperature measurement.
The different chipsets of the family are not strictly identical, although
-very similar. This driver doesn't handle any specific feature for now,
-with the exception of SMBus PEC. For reference, here comes a non-exhaustive
-list of specific features:
+very similar. For reference, here comes a non-exhaustive list of specific
+features:
LM90:
* Filter and alert configuration register at 0xBF.
* ALERT is triggered by open remote sensor.
* SMBus PEC support for Write Byte and Receive Byte transactions.
-ADT7461
+ADT7461:
* Extended temperature range (breaks compatibility)
* Lower resolution for remote temperature
MAX6657 and MAX6658:
+ * Better local resolution
* Remote sensor type selection
-MAX6659
+MAX6659:
+ * Better local resolution
* Selectable address
* Second critical temperature limit
* Remote sensor type selection
+MAX6680 and MAX6681:
+ * Selectable address
+ * Remote sensor type selection
+
+W83L771AWG/ASG
+ * The AWG and ASG variants only differ in package format.
+ * Filter and alert configuration register at 0xBF
+ * Diode ideality factor configuration (remote sensor) at 0xE3
+ * Moving average (depending on conversion rate)
+
All temperature values are given in degrees Celsius. Resolution
is 1.0 degree for the local temperature, 0.125 degree for the remote
-temperature.
+temperature, except for the 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
other second; 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 and ADT7461) 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
-----------
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 explicitely disabled
+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
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff