[PATCH v4 1/4] uinput: Use monotonic times for uinput timestamps.

From: Deepa Dinamani
Date: Thu Dec 07 2017 - 13:14:12 EST


struct timeval which is part of struct input_event to
maintain the event times is not y2038 safe.

Real time timestamps are also not ideal for input_event
as this time can go backwards as noted in the patch
a80b83b7b8 by John Stultz.

The patch switches the timestamps to use monotonic time
from realtime time. This is assuming no one is using
absolute times from these timestamps.

The structure to maintain input events will be changed
in a different patch.

Signed-off-by: Deepa Dinamani <deepa.kernel@xxxxxxxxx>
---
drivers/input/misc/uinput.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/input/misc/uinput.c b/drivers/input/misc/uinput.c
index 39ddd9a73feb..d521aecbc078 100644
--- a/drivers/input/misc/uinput.c
+++ b/drivers/input/misc/uinput.c
@@ -84,11 +84,14 @@ static int uinput_dev_event(struct input_dev *dev,
unsigned int type, unsigned int code, int value)
{
struct uinput_device *udev = input_get_drvdata(dev);
+ struct timespec64 ts;

udev->buff[udev->head].type = type;
udev->buff[udev->head].code = code;
udev->buff[udev->head].value = value;
- do_gettimeofday(&udev->buff[udev->head].time);
+ ktime_get_ts64(&ts);
+ udev->buff[udev->head].time.tv_sec = ts.tv_sec;
+ udev->buff[udev->head].time.tv_usec = ts.tv_nsec / NSEC_PER_USEC;
udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE;

wake_up_interruptible(&udev->waitq);
--
2.14.1