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Diffstat (limited to 'kernel/Documentation/hwmon/sis5595')
| -rw-r--r-- | kernel/Documentation/hwmon/sis5595 | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/kernel/Documentation/hwmon/sis5595 b/kernel/Documentation/hwmon/sis5595 new file mode 100644 index 000000000..4f8877a34 --- /dev/null +++ b/kernel/Documentation/hwmon/sis5595 @@ -0,0 +1,106 @@ +Kernel driver sis5595 +===================== + +Supported chips: + * Silicon Integrated Systems Corp. SiS5595 Southbridge Hardware Monitor + Prefix: 'sis5595' + Addresses scanned: ISA in PCI-space encoded address + Datasheet: Publicly available at the Silicon Integrated Systems Corp. site. + +Authors: + Kyösti Mälkki <kmalkki@cc.hut.fi>, + Mark D. Studebaker <mdsxyz123@yahoo.com>, + Aurelien Jarno <aurelien@aurel32.net> 2.6 port + + SiS southbridge has a LM78-like chip integrated on the same IC. + This driver is a customized copy of lm78.c + + Supports following revisions: + Version PCI ID PCI Revision + 1 1039/0008 AF or less + 2 1039/0008 B0 or greater + + Note: these chips contain a 0008 device which is incompatible with the + 5595. We recognize these by the presence of the listed + "blacklist" PCI ID and refuse to load. + + NOT SUPPORTED PCI ID BLACKLIST PCI ID + 540 0008 0540 + 550 0008 0550 + 5513 0008 5511 + 5581 0008 5597 + 5582 0008 5597 + 5597 0008 5597 + 630 0008 0630 + 645 0008 0645 + 730 0008 0730 + 735 0008 0735 + + +Module Parameters +----------------- +force_addr=0xaddr Set the I/O base address. Useful for boards + that don't set the address in the BIOS. Does not do a + PCI force; the device must still be present in lspci. + Don't use this unless the driver complains that the + base address is not set. + Example: 'modprobe sis5595 force_addr=0x290' + + +Description +----------- + +The SiS5595 southbridge has integrated hardware monitor functions. It also +has an I2C bus, but this driver only supports the hardware monitor. For the +I2C bus driver see i2c-sis5595. + +The SiS5595 implements zero or one temperature sensor, two fan speed +sensors, four or five voltage sensors, and alarms. + +On the first version of the chip, there are four voltage sensors and one +temperature sensor. + +On the second version of the chip, the temperature sensor (temp) and the +fifth voltage sensor (in4) share a pin which is configurable, but not +through the driver. Sorry. The driver senses the configuration of the pin, +which was hopefully set by the BIOS. + +Temperatures are measured in degrees Celsius. An alarm is triggered once +when the max is crossed; it is also triggered when it drops below the min +value. Measurements are guaranteed between -55 and +125 degrees, with a +resolution of 1 degree. + +Fan rotation speeds are reported in RPM (rotations per minute). An alarm is +triggered if the rotation speed has dropped below a programmable limit. Fan +readings can be divided by a programmable divider (1, 2, 4 or 8) to give +the readings more range or accuracy. Not all RPM values can accurately be +represented, so some rounding is done. With a divider of 2, the lowest +representable value is around 2600 RPM. + +Voltage sensors (also known as IN sensors) report their values in volts. An +alarm is triggered if the voltage has crossed a programmable minimum or +maximum limit. Note that minimum in this case always means 'closest to +zero'; this is important for negative voltage measurements. All voltage +inputs can measure voltages between 0 and 4.08 volts, with a resolution of +0.016 volt. + +In addition to the alarms described above, there is a BTI alarm, which gets +triggered when an external chip has crossed its limits. Usually, this is +connected to some LM75-like chip; if at least one crosses its limits, this +bit gets set. + +If an alarm triggers, it will remain triggered until the hardware register +is read at least once. This means that the cause for the alarm may already +have disappeared! Note that in the current implementation, all hardware +registers are read whenever any data is read (unless it is less than 1.5 +seconds since the last update). This means that you can easily miss +once-only alarms. + +The SiS5595 only updates its values each 1.5 seconds; reading it more often +will do no harm, but will return 'old' values. + +Problems +-------- +Some chips refuse to be enabled. We don't know why. +The driver will recognize this and print a message in dmesg. + |