ab47deb6bb
CONFIG_NO_HZ currently only sets the default value of dynticks config so if PPS kernel consumer needs periodic timer ticks it should depend on !CONFIG_NO_HZ_COMMON instead of !CONFIG_NO_HZ. Otherwise it is possible to enable it even on tickless system which has CONFIG_NO_HZ not set and CONFIG_NO_HZ_IDLE (or CONFIG_NO_HZ_FULL) set. Link: http://lkml.kernel.org/r/57E2B769.50202@maciej.szmigiero.name Signed-off-by: Maciej S. Szmigiero <mail@maciej.szmigiero.name> Acked-by: Rodolfo Giometti <giometti@enneenne.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
48 lines
1.2 KiB
Plaintext
48 lines
1.2 KiB
Plaintext
#
|
|
# PPS support configuration
|
|
#
|
|
|
|
menu "PPS support"
|
|
|
|
config PPS
|
|
tristate "PPS support"
|
|
---help---
|
|
PPS (Pulse Per Second) is a special pulse provided by some GPS
|
|
antennae. Userland can use it to get a high-precision time
|
|
reference.
|
|
|
|
Some antennae's PPS signals are connected with the CD (Carrier
|
|
Detect) pin of the serial line they use to communicate with the
|
|
host. In this case use the SERIAL_LINE client support.
|
|
|
|
Some antennae's PPS signals are connected with some special host
|
|
inputs so you have to enable the corresponding client support.
|
|
|
|
To compile this driver as a module, choose M here: the module
|
|
will be called pps_core.ko.
|
|
if PPS
|
|
|
|
config PPS_DEBUG
|
|
bool "PPS debugging messages"
|
|
help
|
|
Say Y here if you want the PPS support to produce a bunch of debug
|
|
messages to the system log. Select this if you are having a
|
|
problem with PPS support and want to see more of what is going on.
|
|
|
|
config NTP_PPS
|
|
bool "PPS kernel consumer support"
|
|
depends on !NO_HZ_COMMON
|
|
help
|
|
This option adds support for direct in-kernel time
|
|
synchronization using an external PPS signal.
|
|
|
|
It doesn't work on tickless systems at the moment.
|
|
|
|
endif
|
|
|
|
source drivers/pps/clients/Kconfig
|
|
|
|
source drivers/pps/generators/Kconfig
|
|
|
|
endmenu
|