projects / GitHub / mt8127 / android_kernel_alcatel_ttab.git / blame
| Commit | Line | Data |
|---|---|---|
| 7f15b664 RM |
1 | Kernel driver adm1021 |
| 2 | ===================== | |
| 3 | ||
| 4 | Supported chips: | |
| 5 | * Analog Devices ADM1021 | |
| 6 | Prefix: 'adm1021' | |
| 7 | Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e | |
| 8 | Datasheet: Publicly available at the Analog Devices website | |
| 9 | * Analog Devices ADM1021A/ADM1023 | |
| 10 | Prefix: 'adm1023' | |
| 11 | Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e | |
| 12 | Datasheet: Publicly available at the Analog Devices website | |
| 13 | * Genesys Logic GL523SM | |
| 14 | Prefix: 'gl523sm' | |
| 15 | Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e | |
| 16 | Datasheet: | |
| 7f15b664 RM |
17 | * Maxim MAX1617 |
| 18 | Prefix: 'max1617' | |
| 19 | Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e | |
| 20 | Datasheet: Publicly available at the Maxim website | |
| 21 | * Maxim MAX1617A | |
| 22 | Prefix: 'max1617a' | |
| 23 | Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e | |
| 24 | Datasheet: Publicly available at the Maxim website | |
| 25 | * National Semiconductor LM84 | |
| 26 | Prefix: 'lm84' | |
| 27 | Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e | |
| 28 | Datasheet: Publicly available at the National Semiconductor website | |
| 29 | * Philips NE1617 | |
| 30 | Prefix: 'max1617' (probably detected as a max1617) | |
| 31 | Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e | |
| 32 | Datasheet: Publicly available at the Philips website | |
| 33 | * Philips NE1617A | |
| 34 | Prefix: 'max1617' (probably detected as a max1617) | |
| 35 | Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e | |
| 36 | Datasheet: Publicly available at the Philips website | |
| 37 | * TI THMC10 | |
| 38 | Prefix: 'thmc10' | |
| 39 | Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e | |
| 40 | Datasheet: Publicly available at the TI website | |
| 41 | * Onsemi MC1066 | |
| 42 | Prefix: 'mc1066' | |
| 43 | Addresses scanned: I2C 0x18 - 0x1a, 0x29 - 0x2b, 0x4c - 0x4e | |
| 44 | Datasheet: Publicly available at the Onsemi website | |
| 45 | ||
| 46 | ||
| 47 | Authors: | |
| 48 | Frodo Looijaard <frodol@dds.nl>, | |
| 49 | Philip Edelbrock <phil@netroedge.com> | |
| 50 | ||
| 51 | Module Parameters | |
| 52 | ----------------- | |
| 53 | ||
| 54 | * read_only: int | |
| 55 | Don't set any values, read only mode | |
| 56 | ||
| 57 | ||
| 58 | Description | |
| 59 | ----------- | |
| 60 | ||
| 61 | The chips supported by this driver are very similar. The Maxim MAX1617 is | |
| 62 | the oldest; it has the problem that it is not very well detectable. The | |
| 63 | MAX1617A solves that. The ADM1021 is a straight clone of the MAX1617A. | |
| 64 | Ditto for the THMC10. From here on, we will refer to all these chips as | |
| 65 | ADM1021-clones. | |
| 66 | ||
| 67 | The ADM1021 and MAX1617A reports a die code, which is a sort of revision | |
| 68 | code. This can help us pinpoint problems; it is not very useful | |
| 69 | otherwise. | |
| 70 | ||
| 71 | ADM1021-clones implement two temperature sensors. One of them is internal, | |
| 72 | and measures the temperature of the chip itself; the other is external and | |
| 73 | is realised in the form of a transistor-like device. A special alarm | |
| 74 | indicates whether the remote sensor is connected. | |
| 75 | ||
| 76 | Each sensor has its own low and high limits. When they are crossed, the | |
| 77 | corresponding alarm is set and remains on as long as the temperature stays | |
| 78 | out of range. Temperatures are measured in degrees Celsius. Measurements | |
| 79 | are possible between -65 and +127 degrees, with a resolution of one degree. | |
| 80 | ||
| 81 | If an alarm triggers, it will remain triggered until the hardware register | |
| 82 | is read at least once. This means that the cause for the alarm may already | |
| 83 | have disappeared! | |
| 84 | ||
| 85 | This driver only updates its values each 1.5 seconds; reading it more often | |
| 86 | will do no harm, but will return 'old' values. It is possible to make | |
| 87 | ADM1021-clones do faster measurements, but there is really no good reason | |
| 88 | for that. | |
| 89 | ||
| 7f15b664 | 90 | |
| d7ce0335 JD |
91 | Netburst-based Xeon support |
| 92 | --------------------------- | |
| 7f15b664 | 93 | |
| d7ce0335 JD |
94 | Some Xeon processors based on the Netburst (early Pentium 4, from 2001 to |
| 95 | 2003) microarchitecture had real MAX1617, ADM1021, or compatible chips | |
| 96 | within them, with two temperature sensors. Other Xeon processors of this | |
| 97 | era (with 400 MHz FSB) had chips with only one temperature sensor. | |
| 7f15b664 | 98 | |
| d7ce0335 JD |
99 | If you have such an old Xeon, and you get two valid temperatures when |
| 100 | loading the adm1021 module, then things are good. | |
| 7f15b664 | 101 | |
| d7ce0335 JD |
102 | If nothing happens when loading the adm1021 module, and you are certain |
| 103 | that your specific Xeon processor model includes compatible sensors, you | |
| 104 | will have to explicitly instantiate the sensor chips from user-space. See | |
| 105 | method 4 in Documentation/i2c/instantiating-devices. Possible slave | |
| 106 | addresses are 0x18, 0x1a, 0x29, 0x2b, 0x4c, or 0x4e. It is likely that | |
| 107 | only temp2 will be correct and temp1 will have to be ignored. | |
| 7f15b664 | 108 | |
| d7ce0335 JD |
109 | Previous generations of the Xeon processor (based on Pentium II/III) |
| 110 | didn't have these sensors. Next generations of Xeon processors (533 MHz | |
| 111 | FSB and faster) lost them, until the Core-based generation which | |
| 112 | introduced integrated digital thermal sensors. These are supported by | |
| 113 | the coretemp driver. |