pps: generators: stop the generator on unregister

Both generator drivers stop their timer and then call
pps_gen_unregister_source(): pps_gen_tio_remove() cancels its hrtimer
and disables the TIO, and pps_gen_dummy_exit() deletes its timer. But
/dev/pps-genN and the sysfs "enable" attribute are still there until
the unregister, and a PPS_GEN_SETENABLE or a write to "enable" in
between starts the timer again. Nothing stops it after that: TIO's
hrtimer keeps running in the devm memory freed by the unbind, and the
dummy's timer is left in the unloaded module.

The drivers can't avoid this by unregistering first, as TIO's timer
callback uses pps_gen, which the unregister may free.

Stop the generator in pps_gen_unregister_cdev() instead, under
info_lock after the device and its sysfs files are gone, when nothing
can enable it again. pps_gen_unregister_source() then also does what
its kernel-doc says: "it disables the generator so no pulses are
generated anymore".

Fixes: 86b525bed275 ("drivers pps: add PPS generators support")
Cc: stable@vger.kernel.org
Suggested-by: Rodolfo Giometti <giometti@enneenne.com>
Assisted-by: LLM
Signed-off-by: Danish Khateeb <danishkhateeb03@gmail.com>
Acked-by: Rodolfo Giometti <giometti@enneenne.com>
Link: https://patch.msgid.link/20260929124937.51114-4-danishkhateeb03@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

0 files changed, 0 insertions, 0 deletions