74 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			74 lines
		
	
	
		
			3.1 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
| Kernel driver gl518sm
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| =====================
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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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|   * 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/
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| 
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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 <jdelvare@suse.de>
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| 
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| Description
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| -----------
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| 
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| IMPORTANT:
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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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