| Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame^] | 1 | # |
| 2 | # PPS support configuration |
| 3 | # |
| 4 | |
| 5 | menuconfig PPS |
| 6 | tristate "PPS support" |
| 7 | ---help--- |
| 8 | PPS (Pulse Per Second) is a special pulse provided by some GPS |
| 9 | antennae. Userland can use it to get a high-precision time |
| 10 | reference. |
| 11 | |
| 12 | Some antennae's PPS signals are connected with the CD (Carrier |
| 13 | Detect) pin of the serial line they use to communicate with the |
| 14 | host. In this case use the SERIAL_LINE client support. |
| 15 | |
| 16 | Some antennae's PPS signals are connected with some special host |
| 17 | inputs so you have to enable the corresponding client support. |
| 18 | |
| 19 | To compile this driver as a module, choose M here: the module |
| 20 | will be called pps_core.ko. |
| 21 | |
| 22 | if PPS |
| 23 | |
| 24 | config PPS_DEBUG |
| 25 | bool "PPS debugging messages" |
| 26 | help |
| 27 | Say Y here if you want the PPS support to produce a bunch of debug |
| 28 | messages to the system log. Select this if you are having a |
| 29 | problem with PPS support and want to see more of what is going on. |
| 30 | |
| 31 | config NTP_PPS |
| 32 | bool "PPS kernel consumer support" |
| 33 | depends on !NO_HZ_COMMON |
| 34 | help |
| 35 | This option adds support for direct in-kernel time |
| 36 | synchronization using an external PPS signal. |
| 37 | |
| 38 | It doesn't work on tickless systems at the moment. |
| 39 | |
| 40 | source drivers/pps/clients/Kconfig |
| 41 | |
| 42 | source drivers/pps/generators/Kconfig |
| 43 | |
| 44 | endif # PPS |