46 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
		
		
			
		
	
	
			46 lines
		
	
	
		
			1.3 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
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								# SPDX-License-Identifier: GPL-2.0-only
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								#
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								# PPS support configuration
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								#
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								menuconfig PPS
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									tristate "PPS support"
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									help
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									  PPS (Pulse Per Second) is a special pulse provided by some GPS
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									  antennae. Userland can use it to get a high-precision time
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									  reference.
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									  Some antennae's PPS signals are connected with the CD (Carrier
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									  Detect) pin of the serial line they use to communicate with the
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									  host. In this case use the SERIAL_LINE client support.
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									  Some antennae's PPS signals are connected with some special host
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									  inputs so you have to enable the corresponding client support.
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									  To compile this driver as a module, choose M here: the module
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									  will be called pps_core.ko.
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								if PPS
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								config PPS_DEBUG
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									bool "PPS debugging messages"
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									help
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									  Say Y here if you want the PPS support to produce a bunch of debug
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									  messages to the system log.  Select this if you are having a
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									  problem with PPS support and want to see more of what is going on.
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								config NTP_PPS
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									bool "PPS kernel consumer support"
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									depends on !NO_HZ_COMMON
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									help
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									  This option adds support for direct in-kernel time
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									  synchronization using an external PPS signal.
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									  It doesn't work on tickless systems at the moment.
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								source "drivers/pps/clients/Kconfig"
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								source "drivers/pps/generators/Kconfig"
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								endif # PPS
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