| xj | b04a402 | 2021-11-25 15:01:52 +0800 | [diff] [blame] | 1 | Kernel driver adm1025 |
| 2 | ===================== |
| 3 | |
| 4 | Supported chips: |
| 5 | * Analog Devices ADM1025, ADM1025A |
| 6 | Prefix: 'adm1025' |
| 7 | Addresses scanned: I2C 0x2c - 0x2e |
| 8 | Datasheet: Publicly available at the Analog Devices website |
| 9 | * Philips NE1619 |
| 10 | Prefix: 'ne1619' |
| 11 | Addresses scanned: I2C 0x2c - 0x2d |
| 12 | Datasheet: Publicly available at the Philips website |
| 13 | |
| 14 | The NE1619 presents some differences with the original ADM1025: |
| 15 | * Only two possible addresses (0x2c - 0x2d). |
| 16 | * No temperature offset register, but we don't use it anyway. |
| 17 | * No INT mode for pin 16. We don't play with it anyway. |
| 18 | |
| 19 | Authors: |
| 20 | Chen-Yuan Wu <gwu@esoft.com>, |
| 21 | Jean Delvare <jdelvare@suse.de> |
| 22 | |
| 23 | Description |
| 24 | ----------- |
| 25 | |
| 26 | (This is from Analog Devices.) The ADM1025 is a complete system hardware |
| 27 | monitor for microprocessor-based systems, providing measurement and limit |
| 28 | comparison of various system parameters. Five voltage measurement inputs |
| 29 | are provided, for monitoring +2.5V, +3.3V, +5V and +12V power supplies and |
| 30 | the processor core voltage. The ADM1025 can monitor a sixth power-supply |
| 31 | voltage by measuring its own VCC. One input (two pins) is dedicated to a |
| 32 | remote temperature-sensing diode and an on-chip temperature sensor allows |
| 33 | ambient temperature to be monitored. |
| 34 | |
| 35 | One specificity of this chip is that the pin 11 can be hardwired in two |
| 36 | different manners. It can act as the +12V power-supply voltage analog |
| 37 | input, or as the a fifth digital entry for the VID reading (bit 4). It's |
| 38 | kind of strange since both are useful, and the reason for designing the |
| 39 | chip that way is obscure at least to me. The bit 5 of the configuration |
| 40 | register can be used to define how the chip is hardwired. Please note that |
| 41 | it is not a choice you have to make as the user. The choice was already |
| 42 | made by your motherboard's maker. If the configuration bit isn't set |
| 43 | properly, you'll have a wrong +12V reading or a wrong VID reading. The way |
| 44 | the driver handles that is to preserve this bit through the initialization |
| 45 | process, assuming that the BIOS set it up properly beforehand. If it turns |
| 46 | out not to be true in some cases, we'll provide a module parameter to force |
| 47 | modes. |
| 48 | |
| 49 | This driver also supports the ADM1025A, which differs from the ADM1025 |
| 50 | only in that it has "open-drain VID inputs while the ADM1025 has on-chip |
| 51 | 100k pull-ups on the VID inputs". It doesn't make any difference for us. |