[media] v4l: Helper function for obtaining timestamps

v4l2_get_timestamp() produces a monotonic timestamp but unlike
ktime_get_ts(), it uses struct timeval instead of struct timespec, saving
the drivers the conversion job when getting timestamps for v4l2_buffer's
timestamp field.

Signed-off-by: Sakari Ailus <sakari.ailus@iki.fi>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
Sakari Ailus 2012-09-15 07:51:47 -03:00 committed by Mauro Carvalho Chehab
parent 1202ecdc24
commit abd2329564
2 changed files with 12 additions and 0 deletions

View File

@ -978,3 +978,13 @@ const struct v4l2_frmsize_discrete *v4l2_find_nearest_format(
return best; return best;
} }
EXPORT_SYMBOL_GPL(v4l2_find_nearest_format); EXPORT_SYMBOL_GPL(v4l2_find_nearest_format);
void v4l2_get_timestamp(struct timeval *tv)
{
struct timespec ts;
ktime_get_ts(&ts);
tv->tv_sec = ts.tv_sec;
tv->tv_usec = ts.tv_nsec / NSEC_PER_USEC;
}
EXPORT_SYMBOL_GPL(v4l2_get_timestamp);

View File

@ -225,4 +225,6 @@ bool v4l2_detect_gtf(unsigned frame_height, unsigned hfreq, unsigned vsync,
struct v4l2_fract v4l2_calc_aspect_ratio(u8 hor_landscape, u8 vert_portrait); struct v4l2_fract v4l2_calc_aspect_ratio(u8 hor_landscape, u8 vert_portrait);
void v4l2_get_timestamp(struct timeval *tv);
#endif /* V4L2_COMMON_H_ */ #endif /* V4L2_COMMON_H_ */