On Wed, Dec 21, 2011 at 9:41 AM, Wanlong Gao <gaowanlong@xxxxxxxxxxxxxx> wrote: > On 12/21/2011 09:01 AM, john stultz wrote: > >> Hi >> In reviewing the Android patch set, I noticed the following patch from >> Arve which looks like it resolves a reasonable issue (events using >> CLOCK_REALTIME timestamps, which can jump forwards or backwards via >> settimeofday()). >> >> I'm not very familiar with the evdev interface, so I'm not sure if >> changing the timestamps to CLOCK_MONOTONIC could cause an ABI problem >> with legacy apps. Even so, I wanted to send the patch out for review and >> consideration as it seems like a reasonable fix. Maybe you will have more luck this time. You can read the previous thread on this exact topic, here: https://lkml.org/lkml/2011/10/3/37 The previous attempt got bogged down when people wanted more data on use cases and how this patch would promote world peace. I strongly support the concept, but we found other ways to address our major concern at the time, so didn't invest more effort to get that patch accepted. Just a question though, why ktime_get_ts() and not getrawmonotonic()? Thanks! >> >> thanks >> -john >> >> >> >>>From 20950b728f120cd808965c1a20b024aa79706d8d Mon Sep 17 00:00:00 2001 >> From: =?UTF-8?q?=3D=3FUTF-8=3Fq=3FArve=3D20Hj=3DC3=3DB8nnev=3DC3=3DA5g=3F=3D?= <arve@xxxxxxxxxxx> >> Date: Fri, 2 Dec 2011 13:59:05 +0800 >> Subject: [PATCH] Input: Use monotonic time for event time stamps. >> MIME-Version: 1.0 >> Content-Type: text/plain; charset=UTF-8 >> Content-Transfer-Encoding: 8bit >> >> Since wall time can jump backwards, it cannot be used to determine if one >> event occured before another or for how long a key was pressed. > > seems reasonable. > >> >> CC: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx> >> CC: linux-input@xxxxxxxxxxxxxxx >> Signed-off-by: Arve Hjønnevåg <arve@xxxxxxxxxxx> >> Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx> >> --- >> drivers/input/evdev.c | 5 ++++- >> 1 files changed, 4 insertions(+), 1 deletions(-) >> >> diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c >> index 4cf2534..ec329b4 100644 >> --- a/drivers/input/evdev.c >> +++ b/drivers/input/evdev.c >> @@ -94,8 +94,11 @@ static void evdev_event(struct input_handle *handle, >> struct evdev *evdev = handle->private; >> struct evdev_client *client; >> struct input_event event; >> + struct timespec ts; >> >> - do_gettimeofday(&event.time); >> + ktime_get_ts(&ts); >> + event.time.tv_sec = ts.tv_sec; >> + event.time.tv_usec = ts.tv_nsec / NSEC_PER_USEC; >> event.type = type; >> event.code = code; >> event.value = value; -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
