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Diffstat (limited to 'Documentation/i2c/chips/lm87')
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diff --git a/Documentation/i2c/chips/lm87 b/Documentation/i2c/chips/lm87 deleted file mode 100644 index c952c57f0e11..000000000000 --- a/Documentation/i2c/chips/lm87 +++ /dev/null @@ -1,73 +0,0 @@ -Kernel driver lm87 -================== - -Supported chips: - * National Semiconductor LM87 - Prefix: 'lm87' - Addresses scanned: I2C 0x2c - 0x2f - Datasheet: http://www.national.com/pf/LM/LM87.html - -Authors: - Frodo Looijaard <frodol@dds.nl>, - Philip Edelbrock <phil@netroedge.com>, - Mark Studebaker <mdsxyz123@yahoo.com>, - Stephen Rousset <stephen.rousset@rocketlogix.com>, - Dan Eaton <dan.eaton@rocketlogix.com>, - Jean Delvare <khali@linux-fr.org>, - Original 2.6 port Jeff Oliver - -Description ------------ - -This driver implements support for the National Semiconductor LM87. - -The LM87 implements up to three temperature sensors, up to two fan -rotation speed sensors, up to seven voltage sensors, alarms, and some -miscellaneous stuff. - -Temperatures are measured in degrees Celsius. Each input has a high -and low alarm settings. A high limit produces an alarm when the value -goes above it, and an alarm is also produced when the value goes below -the low limit. - -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 -the readings more range or accuracy. Not all RPM values can accurately be -represented, so some rounding is done. With a divider of 2, the lowest -representable value is around 2600 RPM. - -Voltage sensors (also known as IN sensors) report their values in -volts. An alarm is triggered if the voltage has crossed a programmable -minimum or maximum limit. Note that minimum in this case always means -'closest to zero'; this is important for negative voltage measurements. - -If an alarm triggers, it will remain triggered until the hardware register -is read at least once. This means that the cause for the alarm may -already have disappeared! Note that in the current implementation, all -hardware registers are read whenever any data is read (unless it is less -than 1.0 seconds since the last update). This means that you can easily -miss once-only alarms. - -The lm87 driver only updates its values each 1.0 seconds; reading it more -often will do no harm, but will return 'old' values. - - -Hardware Configurations ------------------------ - -The LM87 has four pins which can serve one of two possible functions, -depending on the hardware configuration. - -Some functions share pins, so not all functions are available at the same -time. Which are depends on the hardware setup. This driver assumes that -the BIOS configured the chip correctly. In that respect, it differs from -the original driver (from lm_sensors for Linux 2.4), which would force the -LM87 to an arbitrary, compile-time chosen mode, regardless of the actual -chipset wiring. - -For reference, here is the list of exclusive functions: - - in0+in5 (default) or temp3 - - fan1 (default) or in6 - - fan2 (default) or in7 - - VID lines (default) or IRQ lines (not handled by this driver) |