diff options
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/i2c/busses/i2c-piix4 | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/Documentation/i2c/busses/i2c-piix4 b/Documentation/i2c/busses/i2c-piix4 index a706ae6a1b41..921476333235 100644 --- a/Documentation/i2c/busses/i2c-piix4 +++ b/Documentation/i2c/busses/i2c-piix4 | |||
@@ -82,3 +82,17 @@ the SMI mode. | |||
82 | 82 | ||
83 | Please note that you don't need to do that in all cases, just when the SMBus is | 83 | Please note that you don't need to do that in all cases, just when the SMBus is |
84 | not working properly. | 84 | not working properly. |
85 | |||
86 | |||
87 | Hardware-specific issues | ||
88 | ------------------------ | ||
89 | |||
90 | This driver will refuse to load on IBM systems with an Intel PIIX4 SMBus. | ||
91 | Some of these machines have an RFID EEPROM (24RF08) connected to the SMBus, | ||
92 | which can easily get corrupted due to a state machine bug. These are mostly | ||
93 | Thinkpad laptops, but desktop systems may also be affected. We have no list | ||
94 | of all affected systems, so the only safe solution was to prevent access to | ||
95 | the SMBus on all IBM systems (detected using DMI data.) | ||
96 | |||
97 | For additional information, read: | ||
98 | http://www2.lm-sensors.nu/~lm78/cvs/lm_sensors2/README.thinkpad | ||