Denis OSTERLAND-HEIM 12c409aa1e pps: fix poll support ... Because pps_cdev_poll() returns unconditionally EPOLLIN, a user space program that calls select/poll get always an immediate data ready-to-read response. As a result the intended use to wait until next data becomes ready does not work. User space snippet: struct pollfd pollfd = { .fd = open("/dev/pps0", O_RDONLY), .events = POLLIN|POLLERR, .revents = 0 }; while(1) { poll(&pollfd, 1, 2000/*ms*/); // returns immediate, but should wait if(revents & EPOLLIN) { // always true struct pps_fdata fdata; memset(&fdata, 0, sizeof(memdata)); ioctl(PPS_FETCH, &fdata); // currently fetches data at max speed } } Lets remember the last fetch event counter and compare this value in pps_cdev_poll() with most recent event counter and return 0 if they are equal. Signed-off-by: Denis OSTERLAND-HEIM <denis.osterland@diehl.com> Co-developed-by: Rodolfo Giometti <giometti@enneenne.com> Signed-off-by: Rodolfo Giometti <giometti@enneenne.com> Fixes: eae9d2ba0c ("LinuxPPS: core support") Link: https://lore.kernel.org/all/f6bed779-6d59-4f0f-8a59-b6312bd83b4e@enneenne.com/ Acked-by: Rodolfo Giometti <giometti@enneenne.com> Link: https://lore.kernel.org/r/c3c50ad1eb19ef553eca8a57c17f4c006413ab70.camel@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2025-07-01 12:29:29 +02:00
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clients
generators
kapi.c
kc.c
kc.h
Kconfig
Makefile
pps.c	pps: fix poll support	2025-07-01 12:29:29 +02:00
sysfs.c