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diff --git a/Documentation/hwmon/lm90 b/Documentation/hwmon/lm90 deleted file mode 100644 index 8122675d30f6..000000000000 --- a/Documentation/hwmon/lm90 +++ /dev/null @@ -1,275 +0,0 @@ -Kernel driver lm90 -================== - -Supported chips: - * 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 ADM1032 - Prefix: '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 - * Analog Devices ADT7461A - Prefix: 'adt7461a' - Addresses scanned: I2C 0x4c and 0x4d - Datasheet: Publicly available at the ON Semiconductor website - http://www.onsemi.com/PowerSolutions/product.do?id=ADT7461A - * ON Semiconductor NCT1008 - Prefix: 'nct1008' - Addresses scanned: I2C 0x4c and 0x4d - Datasheet: Publicly available at the ON Semiconductor website - http://www.onsemi.com/PowerSolutions/product.do?id=NCT1008 - * 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 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 - 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: 'max6646' - 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 - http://www.ti.com/litv/pdf/sbos686 - - -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. - -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 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. For reference, here comes a non-exhaustive list of specific -features: - -LM90: - * 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 - -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 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 can be disabled through -sysfs. Just write 0 to the "pec" file and PEC will be disabled. Write 1 -to that file to enable PEC again. |