162306a36Sopenharmony_ci# SPDX-License-Identifier: GPL-2.0-only 262306a36Sopenharmony_ci# 362306a36Sopenharmony_ci# PPS support configuration 462306a36Sopenharmony_ci# 562306a36Sopenharmony_ci 662306a36Sopenharmony_cimenuconfig PPS 762306a36Sopenharmony_ci tristate "PPS support" 862306a36Sopenharmony_ci help 962306a36Sopenharmony_ci PPS (Pulse Per Second) is a special pulse provided by some GPS 1062306a36Sopenharmony_ci antennae. Userland can use it to get a high-precision time 1162306a36Sopenharmony_ci reference. 1262306a36Sopenharmony_ci 1362306a36Sopenharmony_ci Some antennae's PPS signals are connected with the CD (Carrier 1462306a36Sopenharmony_ci Detect) pin of the serial line they use to communicate with the 1562306a36Sopenharmony_ci host. In this case use the SERIAL_LINE client support. 1662306a36Sopenharmony_ci 1762306a36Sopenharmony_ci Some antennae's PPS signals are connected with some special host 1862306a36Sopenharmony_ci inputs so you have to enable the corresponding client support. 1962306a36Sopenharmony_ci 2062306a36Sopenharmony_ci To compile this driver as a module, choose M here: the module 2162306a36Sopenharmony_ci will be called pps_core.ko. 2262306a36Sopenharmony_ci 2362306a36Sopenharmony_ciif PPS 2462306a36Sopenharmony_ci 2562306a36Sopenharmony_ciconfig PPS_DEBUG 2662306a36Sopenharmony_ci bool "PPS debugging messages" 2762306a36Sopenharmony_ci help 2862306a36Sopenharmony_ci Say Y here if you want the PPS support to produce a bunch of debug 2962306a36Sopenharmony_ci messages to the system log. Select this if you are having a 3062306a36Sopenharmony_ci problem with PPS support and want to see more of what is going on. 3162306a36Sopenharmony_ci 3262306a36Sopenharmony_ciconfig NTP_PPS 3362306a36Sopenharmony_ci bool "PPS kernel consumer support" 3462306a36Sopenharmony_ci depends on !NO_HZ_COMMON 3562306a36Sopenharmony_ci help 3662306a36Sopenharmony_ci This option adds support for direct in-kernel time 3762306a36Sopenharmony_ci synchronization using an external PPS signal. 3862306a36Sopenharmony_ci 3962306a36Sopenharmony_ci It doesn't work on tickless systems at the moment. 4062306a36Sopenharmony_ci 4162306a36Sopenharmony_cisource "drivers/pps/clients/Kconfig" 4262306a36Sopenharmony_ci 4362306a36Sopenharmony_cisource "drivers/pps/generators/Kconfig" 4462306a36Sopenharmony_ci 4562306a36Sopenharmony_ciendif # PPS 46