18c2ecf20Sopenharmony_ci# SPDX-License-Identifier: GPL-2.0-only
28c2ecf20Sopenharmony_ci#
38c2ecf20Sopenharmony_ci# PPS support configuration
48c2ecf20Sopenharmony_ci#
58c2ecf20Sopenharmony_ci
68c2ecf20Sopenharmony_cimenuconfig PPS
78c2ecf20Sopenharmony_ci	tristate "PPS support"
88c2ecf20Sopenharmony_ci	help
98c2ecf20Sopenharmony_ci	  PPS (Pulse Per Second) is a special pulse provided by some GPS
108c2ecf20Sopenharmony_ci	  antennae. Userland can use it to get a high-precision time
118c2ecf20Sopenharmony_ci	  reference.
128c2ecf20Sopenharmony_ci
138c2ecf20Sopenharmony_ci	  Some antennae's PPS signals are connected with the CD (Carrier
148c2ecf20Sopenharmony_ci	  Detect) pin of the serial line they use to communicate with the
158c2ecf20Sopenharmony_ci	  host. In this case use the SERIAL_LINE client support.
168c2ecf20Sopenharmony_ci
178c2ecf20Sopenharmony_ci	  Some antennae's PPS signals are connected with some special host
188c2ecf20Sopenharmony_ci	  inputs so you have to enable the corresponding client support.
198c2ecf20Sopenharmony_ci
208c2ecf20Sopenharmony_ci	  To compile this driver as a module, choose M here: the module
218c2ecf20Sopenharmony_ci	  will be called pps_core.ko.
228c2ecf20Sopenharmony_ci
238c2ecf20Sopenharmony_ciif PPS
248c2ecf20Sopenharmony_ci
258c2ecf20Sopenharmony_ciconfig PPS_DEBUG
268c2ecf20Sopenharmony_ci	bool "PPS debugging messages"
278c2ecf20Sopenharmony_ci	help
288c2ecf20Sopenharmony_ci	  Say Y here if you want the PPS support to produce a bunch of debug
298c2ecf20Sopenharmony_ci	  messages to the system log.  Select this if you are having a
308c2ecf20Sopenharmony_ci	  problem with PPS support and want to see more of what is going on.
318c2ecf20Sopenharmony_ci
328c2ecf20Sopenharmony_ciconfig NTP_PPS
338c2ecf20Sopenharmony_ci	bool "PPS kernel consumer support"
348c2ecf20Sopenharmony_ci	depends on !NO_HZ_COMMON
358c2ecf20Sopenharmony_ci	help
368c2ecf20Sopenharmony_ci	  This option adds support for direct in-kernel time
378c2ecf20Sopenharmony_ci	  synchronization using an external PPS signal.
388c2ecf20Sopenharmony_ci
398c2ecf20Sopenharmony_ci	  It doesn't work on tickless systems at the moment.
408c2ecf20Sopenharmony_ci
418c2ecf20Sopenharmony_cisource "drivers/pps/clients/Kconfig"
428c2ecf20Sopenharmony_ci
438c2ecf20Sopenharmony_cisource "drivers/pps/generators/Kconfig"
448c2ecf20Sopenharmony_ci
458c2ecf20Sopenharmony_ciendif # PPS
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