0001 Kernel driver adm1025
0002 =====================
0003
0004 Supported chips:
0005
0006 * Analog Devices ADM1025, ADM1025A
0007
0008 Prefix: 'adm1025'
0009
0010 Addresses scanned: I2C 0x2c - 0x2e
0011
0012 Datasheet: Publicly available at the Analog Devices website
0013
0014 * Philips NE1619
0015
0016 Prefix: 'ne1619'
0017
0018 Addresses scanned: I2C 0x2c - 0x2d
0019
0020 Datasheet: Publicly available at the Philips website
0021
0022 The NE1619 presents some differences with the original ADM1025:
0023
0024 * Only two possible addresses (0x2c - 0x2d).
0025 * No temperature offset register, but we don't use it anyway.
0026 * No INT mode for pin 16. We don't play with it anyway.
0027
0028 Authors:
0029 - Chen-Yuan Wu <gwu@esoft.com>,
0030 - Jean Delvare <jdelvare@suse.de>
0031
0032 Description
0033 -----------
0034
0035 (This is from Analog Devices.) The ADM1025 is a complete system hardware
0036 monitor for microprocessor-based systems, providing measurement and limit
0037 comparison of various system parameters. Five voltage measurement inputs
0038 are provided, for monitoring +2.5V, +3.3V, +5V and +12V power supplies and
0039 the processor core voltage. The ADM1025 can monitor a sixth power-supply
0040 voltage by measuring its own VCC. One input (two pins) is dedicated to a
0041 remote temperature-sensing diode and an on-chip temperature sensor allows
0042 ambient temperature to be monitored.
0043
0044 One specificity of this chip is that the pin 11 can be hardwired in two
0045 different manners. It can act as the +12V power-supply voltage analog
0046 input, or as the a fifth digital entry for the VID reading (bit 4). It's
0047 kind of strange since both are useful, and the reason for designing the
0048 chip that way is obscure at least to me. The bit 5 of the configuration
0049 register can be used to define how the chip is hardwired. Please note that
0050 it is not a choice you have to make as the user. The choice was already
0051 made by your motherboard's maker. If the configuration bit isn't set
0052 properly, you'll have a wrong +12V reading or a wrong VID reading. The way
0053 the driver handles that is to preserve this bit through the initialization
0054 process, assuming that the BIOS set it up properly beforehand. If it turns
0055 out not to be true in some cases, we'll provide a module parameter to force
0056 modes.
0057
0058 This driver also supports the ADM1025A, which differs from the ADM1025
0059 only in that it has "open-drain VID inputs while the ADM1025 has on-chip
0060 100k pull-ups on the VID inputs". It doesn't make any difference for us.
