adm1025.rst (2361B)
1Kernel driver adm1025 2===================== 3 4Supported chips: 5 6 * Analog Devices ADM1025, ADM1025A 7 8 Prefix: 'adm1025' 9 10 Addresses scanned: I2C 0x2c - 0x2e 11 12 Datasheet: Publicly available at the Analog Devices website 13 14 * Philips NE1619 15 16 Prefix: 'ne1619' 17 18 Addresses scanned: I2C 0x2c - 0x2d 19 20 Datasheet: Publicly available at the Philips website 21 22The NE1619 presents some differences with the original ADM1025: 23 24 * Only two possible addresses (0x2c - 0x2d). 25 * No temperature offset register, but we don't use it anyway. 26 * No INT mode for pin 16. We don't play with it anyway. 27 28Authors: 29 - Chen-Yuan Wu <gwu@esoft.com>, 30 - Jean Delvare <jdelvare@suse.de> 31 32Description 33----------- 34 35(This is from Analog Devices.) The ADM1025 is a complete system hardware 36monitor for microprocessor-based systems, providing measurement and limit 37comparison of various system parameters. Five voltage measurement inputs 38are provided, for monitoring +2.5V, +3.3V, +5V and +12V power supplies and 39the processor core voltage. The ADM1025 can monitor a sixth power-supply 40voltage by measuring its own VCC. One input (two pins) is dedicated to a 41remote temperature-sensing diode and an on-chip temperature sensor allows 42ambient temperature to be monitored. 43 44One specificity of this chip is that the pin 11 can be hardwired in two 45different manners. It can act as the +12V power-supply voltage analog 46input, or as the a fifth digital entry for the VID reading (bit 4). It's 47kind of strange since both are useful, and the reason for designing the 48chip that way is obscure at least to me. The bit 5 of the configuration 49register can be used to define how the chip is hardwired. Please note that 50it is not a choice you have to make as the user. The choice was already 51made by your motherboard's maker. If the configuration bit isn't set 52properly, you'll have a wrong +12V reading or a wrong VID reading. The way 53the driver handles that is to preserve this bit through the initialization 54process, assuming that the BIOS set it up properly beforehand. If it turns 55out not to be true in some cases, we'll provide a module parameter to force 56modes. 57 58This driver also supports the ADM1025A, which differs from the ADM1025 59only in that it has "open-drain VID inputs while the ADM1025 has on-chip 60100k pull-ups on the VID inputs". It doesn't make any difference for us.