1Kernel driver ds620 2=================== 3 4Supported chips: 5 * Dallas Semiconductor DS620 6 Prefix: 'ds620' 7 Datasheet: Publicly available at the Dallas Semiconductor website 8 http://www.dalsemi.com/ 9 10Authors: 11 Roland Stigge <stigge@antcom.de> 12 based on ds1621.c by 13 Christian W. Zuckschwerdt <zany@triq.net> 14 15Description 16----------- 17 18The DS620 is a (one instance) digital thermometer and thermostat. It has both 19high and low temperature limits which can be user defined (i.e. programmed 20into non-volatile on-chip registers). Temperature range is -55 degree Celsius 21to +125. Between 0 and 70 degree Celsius, accuracy is 0.5 Kelvin. The value 22returned via sysfs displays post decimal positions. 23 24The thermostat function works as follows: When configured via platform_data 25(struct ds620_platform_data) .pomode == 0 (default), the thermostat output pin 26PO is always low. If .pomode == 1, the thermostat is in PO_LOW mode. I.e., the 27output pin PO becomes active when the temperature falls below temp1_min and 28stays active until the temperature goes above temp1_max. 29 30Likewise, with .pomode == 2, the thermostat is in PO_HIGH mode. I.e., the PO 31output pin becomes active when the temperature goes above temp1_max and stays 32active until the temperature falls below temp1_min. 33 34The PO output pin of the DS620 operates active-low. 35