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+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.
+