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Add SPDX license identifiers to all Make/Kconfig files which: - Have no license information of any form These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
46 lines
1.3 KiB
Plaintext
46 lines
1.3 KiB
Plaintext
# 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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