emc2103.rst (1262B)
1Kernel driver emc2103 2====================== 3 4Supported chips: 5 6 * SMSC EMC2103 7 8 Addresses scanned: I2C 0x2e 9 10 Prefix: 'emc2103' 11 12 Datasheet: Not public 13 14Authors: 15 Steve Glendinning <steve.glendinning@smsc.com> 16 17Description 18----------- 19 20The Standard Microsystems Corporation (SMSC) EMC2103 chips 21contain up to 4 temperature sensors and a single fan controller. 22 23Fan rotation speeds are reported in RPM (rotations per minute). An alarm is 24triggered if the rotation speed has dropped below a programmable limit. Fan 25readings can be divided by a programmable divider (1, 2, 4 or 8) to give 26the readings more range or accuracy. Not all RPM values can accurately be 27represented, so some rounding is done. With a divider of 1, the lowest 28representable value is 480 RPM. 29 30This driver supports RPM based control, to use this a fan target 31should be written to fan1_target and pwm1_enable should be set to 3. 32 33The 2103-2 and 2103-4 variants have a third temperature sensor, which can 34be connected to two anti-parallel diodes. These values can be read 35as temp3 and temp4. If only one diode is attached to this channel, temp4 36will show as "fault". The module parameter "apd=0" can be used to suppress 37this 4th channel when anti-parallel diodes are not fitted.