ede7fbdf52
Part 3: Move the drivers documentation, plus two general documentation files. Note that the patch "adds trailing whitespace", because it does move the files as-is, and some files happen to have trailing whitespace. Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
74 lines
3.2 KiB
Text
74 lines
3.2 KiB
Text
Kernel driver gl518sm
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=====================
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Supported chips:
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* Genesys Logic GL518SM release 0x00
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Prefix: 'gl518sm'
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Addresses scanned: I2C 0x2c and 0x2d
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Datasheet: http://www.genesyslogic.com/pdf
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* Genesys Logic GL518SM release 0x80
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Prefix: 'gl518sm'
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Addresses scanned: I2C 0x2c and 0x2d
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Datasheet: http://www.genesyslogic.com/pdf
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Authors:
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Frodo Looijaard <frodol@dds.nl>,
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Kyösti Mälkki <kmalkki@cc.hut.fi>
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Hong-Gunn Chew <hglinux@gunnet.org>
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Jean Delvare <khali@linux-fr.org>
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Description
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-----------
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IMPORTANT:
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For the revision 0x00 chip, the in0, in1, and in2 values (+5V, +3V,
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and +12V) CANNOT be read. This is a limitation of the chip, not the driver.
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This driver supports the Genesys Logic GL518SM chip. There are at least
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two revision of this chip, which we call revision 0x00 and 0x80. Revision
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0x80 chips support the reading of all voltages and revision 0x00 only
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for VIN3.
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The GL518SM implements one temperature sensor, two fan rotation speed
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sensors, and four voltage sensors. It can report alarms through the
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computer speakers.
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Temperatures are measured in degrees Celsius. An alarm goes off while the
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temperature is above the over temperature limit, and has not yet dropped
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below the hysteresis limit. The alarm always reflects the current
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situation. Measurements are guaranteed between -10 degrees and +110
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degrees, with a accuracy of +/-3 degrees.
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Rotation speeds are reported in RPM (rotations per minute). An alarm is
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triggered if the rotation speed has dropped below a programmable limit. In
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case when you have selected to turn fan1 off, no fan1 alarm is triggered.
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Fan readings can be divided by a programmable divider (1, 2, 4 or 8) to
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give the readings more range or accuracy. Not all RPM values can
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accurately be represented, so some rounding is done. With a divider
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of 2, the lowest representable value is around 1900 RPM.
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Voltage sensors (also known as VIN sensors) report their values in volts.
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An alarm is triggered if the voltage has crossed a programmable minimum or
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maximum limit. Note that minimum in this case always means 'closest to
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zero'; this is important for negative voltage measurements. The VDD input
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measures voltages between 0.000 and 5.865 volt, with a resolution of 0.023
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volt. The other inputs measure voltages between 0.000 and 4.845 volt, with
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a resolution of 0.019 volt. Note that revision 0x00 chips do not support
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reading the current voltage of any input except for VIN3; limit setting and
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alarms work fine, though.
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When an alarm is triggered, you can be warned by a beeping signal through your
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computer speaker. It is possible to enable all beeping globally, or only the
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beeping for some alarms.
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If an alarm triggers, it will remain triggered until the hardware register
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is read at least once (except for temperature alarms). This means that the
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cause for the alarm may already have disappeared! Note that in the current
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implementation, all hardware registers are read whenever any data is read
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(unless it is less than 1.5 seconds since the last update). This means that
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you can easily miss once-only alarms.
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The GL518SM only updates its values each 1.5 seconds; reading it more often
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will do no harm, but will return 'old' values.
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