1Kernel driver emc1403 2===================== 3 4Supported chips: 5 6 * SMSC / Microchip EMC1402, EMC1412 7 8 Addresses scanned: I2C 0x18, 0x1c, 0x29, 0x4c, 0x4d, 0x5c 9 10 Prefix: 'emc1402' 11 12 Datasheets: 13 14 - http://ww1.microchip.com/downloads/en/DeviceDoc/1412.pdf 15 - http://ww1.microchip.com/downloads/en/DeviceDoc/1402.pdf 16 17 * SMSC / Microchip EMC1403, EMC1404, EMC1413, EMC1414 18 19 Addresses scanned: I2C 0x18, 0x29, 0x4c, 0x4d 20 21 Prefix: 'emc1403', 'emc1404' 22 23 Datasheets: 24 25 - http://ww1.microchip.com/downloads/en/DeviceDoc/1403_1404.pdf 26 - http://ww1.microchip.com/downloads/en/DeviceDoc/1413_1414.pdf 27 28 * SMSC / Microchip EMC1422 29 30 Addresses scanned: I2C 0x4c 31 32 Prefix: 'emc1422' 33 34 Datasheet: 35 36 - http://ww1.microchip.com/downloads/en/DeviceDoc/1422.pdf 37 38 * SMSC / Microchip EMC1423, EMC1424 39 40 Addresses scanned: I2C 0x4c 41 42 Prefix: 'emc1423', 'emc1424' 43 44 Datasheet: 45 46 - http://ww1.microchip.com/downloads/en/DeviceDoc/1423_1424.pdf 47 48Author: 49 Kalhan Trisal <kalhan.trisal@intel.com 50 51 52Description 53----------- 54 55The Standard Microsystems Corporation (SMSC) / Microchip EMC14xx chips 56contain up to four temperature sensors. EMC14x2 support two sensors 57(one internal, one external). EMC14x3 support three sensors (one internal, 58two external), and EMC14x4 support four sensors (one internal, three 59external). 60 61The chips implement three limits for each sensor: low (tempX_min), high 62(tempX_max) and critical (tempX_crit.) The chips also implement an 63hysteresis mechanism which applies to all limits. The relative difference 64is stored in a single register on the chip, which means that the relative 65difference between the limit and its hysteresis is always the same for 66all three limits. 67 68This implementation detail implies the following: 69 70* When setting a limit, its hysteresis will automatically follow, the 71 difference staying unchanged. For example, if the old critical limit 72 was 80 degrees C, and the hysteresis was 75 degrees C, and you change 73 the critical limit to 90 degrees C, then the hysteresis will 74 automatically change to 85 degrees C. 75* The hysteresis values can't be set independently. We decided to make 76 only temp1_crit_hyst writable, while all other hysteresis attributes 77 are read-only. Setting temp1_crit_hyst writes the difference between 78 temp1_crit_hyst and temp1_crit into the chip, and the same relative 79 hysteresis applies automatically to all other limits. 80* The limits should be set before the hysteresis. 81