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1Kernel driver lm872==================3 4Supported chips:5 6 * National Semiconductor LM877 8 Prefix: 'lm87'9 10 Addresses scanned: I2C 0x2c - 0x2e11 12 Datasheet: http://www.national.com/pf/LM/LM87.html13 14 * Analog Devices ADM102415 16 Prefix: 'adm1024'17 18 Addresses scanned: I2C 0x2c - 0x2e19 20 Datasheet: https://www.analog.com/en/prod/0,2877,ADM1024,00.html21 22 23Authors:24 - Frodo Looijaard <frodol@dds.nl>,25 - Philip Edelbrock <phil@netroedge.com>,26 - Mark Studebaker <mdsxyz123@yahoo.com>,27 - Stephen Rousset <stephen.rousset@rocketlogix.com>,28 - Dan Eaton <dan.eaton@rocketlogix.com>,29 - Jean Delvare <jdelvare@suse.de>,30 - Original 2.6 port Jeff Oliver31 32Description33-----------34 35This driver implements support for the National Semiconductor LM8736and the Analog Devices ADM1024.37 38The LM87 implements up to three temperature sensors, up to two fan39rotation speed sensors, up to seven voltage sensors, alarms, and some40miscellaneous stuff. The ADM1024 is fully compatible.41 42Temperatures are measured in degrees Celsius. Each input has a high43and low alarm settings. A high limit produces an alarm when the value44goes above it, and an alarm is also produced when the value goes below45the low limit.46 47Fan rotation speeds are reported in RPM (rotations per minute). An alarm is48triggered if the rotation speed has dropped below a programmable limit. Fan49readings can be divided by a programmable divider (1, 2, 4 or 8) to give50the readings more range or accuracy. Not all RPM values can accurately be51represented, so some rounding is done. With a divider of 2, the lowest52representable value is around 2600 RPM.53 54Voltage sensors (also known as IN sensors) report their values in55volts. An alarm is triggered if the voltage has crossed a programmable56minimum or maximum limit. Note that minimum in this case always means57'closest to zero'; this is important for negative voltage measurements.58 59If an alarm triggers, it will remain triggered until the hardware register60is read at least once. This means that the cause for the alarm may61already have disappeared! Note that in the current implementation, all62hardware registers are read whenever any data is read (unless it is less63than 1.0 seconds since the last update). This means that you can easily64miss once-only alarms.65 66The lm87 driver only updates its values each 1.0 seconds; reading it more67often will do no harm, but will return 'old' values.68 69 70Hardware Configurations71-----------------------72 73The LM87 has four pins which can serve one of two possible functions,74depending on the hardware configuration.75 76Some functions share pins, so not all functions are available at the same77time. Which are depends on the hardware setup. This driver normally78assumes that firmware configured the chip correctly. Where this is not79the case, platform code must set the I2C client's platform_data to point80to a u8 value to be written to the channel register.81 82For reference, here is the list of exclusive functions:83 - in0+in5 (default) or temp384 - fan1 (default) or in685 - fan2 (default) or in786 - VID lines (default) or IRQ lines (not handled by this driver)87