projects / mirror_ubuntu-artful-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| 7f15b664 RM |
1 | Kernel driver w83l785ts |
| 2 | ======================= | |
| 3 | ||
| 4 | Supported chips: | |
| 5 | * Winbond W83L785TS-S | |
| 6 | Prefix: 'w83l785ts' | |
| 7 | Addresses scanned: I2C 0x2e | |
| 8 | Datasheet: Publicly available at the Winbond USA website | |
| 9 | http://www.winbond-usa.com/products/winbond_products/pdfs/PCIC/W83L785TS-S.pdf | |
| 10 | ||
| 11 | Authors: | |
| 7c81c60f | 12 | Jean Delvare <jdelvare@suse.de> |
| 7f15b664 RM |
13 | |
| 14 | Description | |
| 15 | ----------- | |
| 16 | ||
| 17 | The W83L785TS-S is a digital temperature sensor. It senses the | |
| 18 | temperature of a single external diode. The high limit is | |
| 19 | theoretically defined as 85 or 100 degrees C through a combination | |
| 20 | of external resistors, so the user cannot change it. Values seen so | |
| 21 | far suggest that the two possible limits are actually 95 and 110 | |
| 22 | degrees C. The datasheet is rather poor and obviously inaccurate | |
| 23 | on several points including this one. | |
| 24 | ||
| 25 | All temperature values are given in degrees Celsius. Resolution | |
| 26 | is 1.0 degree. See the datasheet for details. | |
| 27 | ||
| 28 | The w83l785ts driver will not update its values more frequently than | |
| 29 | every other second; reading them more often will do no harm, but will | |
| 30 | return 'old' values. | |
| 31 | ||
| 32 | Known Issues | |
| 33 | ------------ | |
| 34 | ||
| 35 | On some systems (Asus), the BIOS is known to interfere with the driver | |
| 4040c415 JD |
36 | and cause read errors. Or maybe the W83L785TS-S chip is simply unreliable, |
| 37 | we don't really know. The driver will retry a given number of times | |
| 7f15b664 RM |
38 | (5 by default) and then give up, returning the old value (or 0 if |
| 39 | there is no old value). It seems to work well enough so that you should | |
| 40 | not notice anything. Thanks to James Bolt for helping test this feature. |