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		b5430a04e9
		
	
	
	
	
		
			
			Signed-off-by: <tomaz.mertelj@guest.arnes.si> Cc: Jean Delvare <khali@linux-fr.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
		
			
				
	
	
		
			103 lines
		
	
	
		
			3.2 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			103 lines
		
	
	
		
			3.2 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
| Kernel driver amc6821
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| =====================
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| 
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| Supported chips:
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| 	Texas Instruments AMC6821
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| 	Prefix: 'amc6821'
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| 	Addresses scanned: 0x18, 0x19, 0x1a, 0x2c, 0x2d, 0x2e, 0x4c, 0x4d, 0x4e
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| 	Datasheet: http://focus.ti.com/docs/prod/folders/print/amc6821.html
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| 
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| Authors:
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| 	Tomaz Mertelj <tomaz.mertelj@guest.arnes.si>
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| 
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| 
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| Description
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| -----------
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| 
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| This driver implements support for the Texas Instruments amc6821 chip.
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| The chip has one on-chip and one remote temperature sensor and one pwm fan
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| regulator.
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| The pwm can be controlled either from software or automatically.
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| 
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| The driver provides the following sensor accesses in sysfs:
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| 
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| temp1_input		ro	on-chip temperature
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| temp1_min		rw	"
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| temp1_max		rw	"
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| temp1_crit	 	rw	"
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| temp1_min_alarm		ro	"
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| temp1_max_alarm		ro	"
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| temp1_crit_alarm	ro	"
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| 
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| temp2_input		ro	remote temperature
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| temp2_min		rw	"
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| temp2_max		rw	"
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| temp2_crit	 	rw	"
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| temp2_min_alarm		ro	"
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| temp2_max_alarm		ro	"
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| temp2_crit_alarm	ro	"
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| temp2_fault		ro	"
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| 
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| fan1_input	 	ro	tachometer speed
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| fan1_min		rw	"
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| fan1_max		rw	"
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| fan1_fault	 	ro	"
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| fan1_div		rw	Fan divisor can be either 2 or 4.
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| 
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| pwm1			rw	pwm1
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| pwm1_enable		rw	regulator mode, 1=open loop, 2=fan controlled
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| 				by remote temperature, 3=fan controlled by
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| 				combination of the on-chip temperature and
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| 				remote-sensor temperature,
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| pwm1_auto_channels_temp ro	1 if pwm_enable==2, 3 if pwm_enable==3
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| pwm1_auto_point1_pwm	ro	Hardwired to 0, shared for both
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| 				temperature channels.
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| pwm1_auto_point2_pwm	rw	This value is shared for both temperature
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| 				channels.
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| pwm1_auto_point3_pwm	rw	Hardwired to 255, shared for both
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| 				temperature channels.
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| 
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| temp1_auto_point1_temp	ro	Hardwired to temp2_auto_point1_temp
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| 				which is rw. Below this temperature fan stops.
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| temp1_auto_point2_temp	rw	The low-temperature limit of the proportional
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| 				range. Below this temperature
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| 				pwm1 = pwm1_auto_point2_pwm. It can go from
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| 				0 degree C to 124 degree C in steps of
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| 				4 degree C. Read it out after writing to get
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| 				the actual value.
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| temp1_auto_point3_temp	rw	Above this temperature fan runs at maximum
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| 				speed. It can go from temp1_auto_point2_temp.
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| 				It can only have certain discrete values
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| 				which depend on temp1_auto_point2_temp and
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| 				pwm1_auto_point2_pwm. Read it out after
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| 				writing to get the actual value.
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| 
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| temp2_auto_point1_temp	rw	Must be between 0 degree C and 63 degree C and
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| 				it defines the passive cooling temperature.
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| 				Below this temperature the fan stops in
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| 				the closed loop mode.
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| temp2_auto_point2_temp	rw	The low-temperature limit of the proportional
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| 				range. Below this temperature
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| 				pwm1 = pwm1_auto_point2_pwm. It can go from
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| 				0 degree C to 124 degree C in steps
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| 				of 4 degree C.
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| 
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| temp2_auto_point3_temp	rw	Above this temperature fan runs at maximum
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| 				speed. It can only have certain discrete
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| 				values which depend on temp2_auto_point2_temp
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| 				and pwm1_auto_point2_pwm. Read it out after
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| 				writing to get actual value.
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| 
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| 
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| Module parameters
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| -----------------
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| 
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| If your board has a BIOS that initializes the amc6821 correctly, you should
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| load the module with: init=0.
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| 
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| If your board BIOS doesn't initialize the chip, or you want
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| different settings, you can set the following parameters:
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| init=1,
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| pwminv: 0 default pwm output, 1 inverts pwm output.
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| 
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