diff options
Diffstat (limited to 'Documentation/hwmon')
| -rw-r--r-- | Documentation/hwmon/it87 | 8 | ||||
| -rw-r--r-- | Documentation/hwmon/lm90 | 47 | ||||
| -rw-r--r-- | Documentation/hwmon/smsc47b397 | 8 | ||||
| -rw-r--r-- | Documentation/hwmon/smsc47m1 | 7 | ||||
| -rw-r--r-- | Documentation/hwmon/sysfs-interface | 3 | ||||
| -rw-r--r-- | Documentation/hwmon/via686a | 17 |
6 files changed, 76 insertions, 14 deletions
diff --git a/Documentation/hwmon/it87 b/Documentation/hwmon/it87 index 0d0195040d88..7f42e441c645 100644 --- a/Documentation/hwmon/it87 +++ b/Documentation/hwmon/it87 @@ -4,18 +4,18 @@ Kernel driver it87 Supported chips: * IT8705F Prefix: 'it87' - Addresses scanned: from Super I/O config space, or default ISA 0x290 (8 I/O ports) + Addresses scanned: from Super I/O config space (8 I/O ports) Datasheet: Publicly available at the ITE website http://www.ite.com.tw/ * IT8712F Prefix: 'it8712' Addresses scanned: I2C 0x28 - 0x2f - from Super I/O config space, or default ISA 0x290 (8 I/O ports) + from Super I/O config space (8 I/O ports) Datasheet: Publicly available at the ITE website http://www.ite.com.tw/ * SiS950 [clone of IT8705F] - Prefix: 'sis950' - Addresses scanned: from Super I/O config space, or default ISA 0x290 (8 I/O ports) + Prefix: 'it87' + Addresses scanned: from Super I/O config space (8 I/O ports) Datasheet: No longer be available Author: Christophe Gauthron <chrisg@0-in.com> diff --git a/Documentation/hwmon/lm90 b/Documentation/hwmon/lm90 index 2c4cf39471f4..438cb24cee5b 100644 --- a/Documentation/hwmon/lm90 +++ b/Documentation/hwmon/lm90 @@ -24,14 +24,14 @@ Supported chips: http://www.national.com/pf/LM/LM86.html * Analog Devices ADM1032 Prefix: 'adm1032' - Addresses scanned: I2C 0x4c + Addresses scanned: I2C 0x4c and 0x4d Datasheet: Publicly available at the Analog Devices website - http://products.analog.com/products/info.asp?product=ADM1032 + http://www.analog.com/en/prod/0,2877,ADM1032,00.html * Analog Devices ADT7461 Prefix: 'adt7461' - Addresses scanned: I2C 0x4c + Addresses scanned: I2C 0x4c and 0x4d Datasheet: Publicly available at the Analog Devices website - http://products.analog.com/products/info.asp?product=ADT7461 + http://www.analog.com/en/prod/0,2877,ADT7461,00.html Note: Only if in ADM1032 compatibility mode * Maxim MAX6657 Prefix: 'max6657' @@ -71,8 +71,8 @@ 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, -but could if there ever was a need for it. For reference, here comes a -non-exhaustive list of specific features: +with the exception of SMBus PEC. For reference, here comes a non-exhaustive +list of specific features: LM90: * Filter and alert configuration register at 0xBF. @@ -91,6 +91,7 @@ ADM1032: * 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 * Extended temperature range (breaks compatibility) @@ -119,3 +120,37 @@ The lm90 driver will not update its values more frequently than every other second; reading them more often will do no harm, but will return 'old' values. +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 explicitely 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. diff --git a/Documentation/hwmon/smsc47b397 b/Documentation/hwmon/smsc47b397 index da9d80c96432..20682f15ae41 100644 --- a/Documentation/hwmon/smsc47b397 +++ b/Documentation/hwmon/smsc47b397 @@ -3,6 +3,7 @@ Kernel driver smsc47b397 Supported chips: * SMSC LPC47B397-NC + * SMSC SCH5307-NS Prefix: 'smsc47b397' Addresses scanned: none, address read from Super I/O config space Datasheet: In this file @@ -12,11 +13,14 @@ Authors: Mark M. Hoffman <mhoffman@lightlink.com> November 23, 2004 -The following specification describes the SMSC LPC47B397-NC sensor chip +The following specification describes the SMSC LPC47B397-NC[1] sensor chip (for which there is no public datasheet available). This document was provided by Craig Kelly (In-Store Broadcast Network) and edited/corrected by Mark M. Hoffman <mhoffman@lightlink.com>. +[1] And SMSC SCH5307-NS, which has a different device ID but is otherwise +compatible. + * * * * * Methods for detecting the HP SIO and reading the thermal data on a dc7100. @@ -127,7 +131,7 @@ OUT DX,AL The registers of interest for identifying the SIO on the dc7100 are Device ID (0x20) and Device Rev (0x21). -The Device ID will read 0X6F +The Device ID will read 0x6F (for SCH5307-NS, 0x81) The Device Rev currently reads 0x01 Obtaining the HWM Base Address. diff --git a/Documentation/hwmon/smsc47m1 b/Documentation/hwmon/smsc47m1 index 34e6478c1425..c15bbe68264e 100644 --- a/Documentation/hwmon/smsc47m1 +++ b/Documentation/hwmon/smsc47m1 @@ -12,6 +12,10 @@ Supported chips: http://www.smsc.com/main/datasheets/47m14x.pdf http://www.smsc.com/main/tools/discontinued/47m15x.pdf http://www.smsc.com/main/datasheets/47m192.pdf + * SMSC LPC47M997 + Addresses scanned: none, address read from Super I/O config space + Prefix: 'smsc47m1' + Datasheet: none Authors: Mark D. Studebaker <mdsxyz123@yahoo.com>, @@ -30,6 +34,9 @@ The 47M15x and 47M192 chips contain a full 'hardware monitoring block' in addition to the fan monitoring and control. The hardware monitoring block is not supported by the driver. +No documentation is available for the 47M997, but it has the same device +ID as the 47M15x and 47M192 chips and seems to be compatible. + Fan rotation speeds are reported in RPM (rotations per minute). An alarm is triggered if the rotation speed has dropped below a programmable limit. Fan readings can be divided by a programmable divider (1, 2, 4 or 8) to give diff --git a/Documentation/hwmon/sysfs-interface b/Documentation/hwmon/sysfs-interface index 346400519d0d..764cdc5480e7 100644 --- a/Documentation/hwmon/sysfs-interface +++ b/Documentation/hwmon/sysfs-interface @@ -272,3 +272,6 @@ beep_mask Bitmask for beep. eeprom Raw EEPROM data in binary form. Read only. + +pec Enable or disable PEC (SMBus only) + Read/Write diff --git a/Documentation/hwmon/via686a b/Documentation/hwmon/via686a index b82014cb7c53..a936fb3824b2 100644 --- a/Documentation/hwmon/via686a +++ b/Documentation/hwmon/via686a @@ -18,8 +18,9 @@ Authors: Module Parameters ----------------- -force_addr=0xaddr Set the I/O base address. Useful for Asus A7V boards - that don't set the address in the BIOS. Does not do a +force_addr=0xaddr Set the I/O base address. Useful for boards that + don't set the address in the BIOS. Look for a BIOS + upgrade before resorting to this. Does not do a PCI force; the via686a must still be present in lspci. Don't use this unless the driver complains that the base address is not set. @@ -63,3 +64,15 @@ miss once-only alarms. The driver only updates its values each 1.5 seconds; reading it more often will do no harm, but will return 'old' values. + +Known Issues +------------ + +This driver handles sensors integrated in some VIA south bridges. It is +possible that a motherboard maker used a VT82C686A/B chip as part of a +product design but was not interested in its hardware monitoring features, +in which case the sensor inputs will not be wired. This is the case of +the Asus K7V, A7V and A7V133 motherboards, to name only a few of them. +So, if you need the force_addr parameter, and end up with values which +don't seem to make any sense, don't look any further: your chip is simply +not wired for hardware monitoring. |
