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| author | Gregor Boirie <gregor.boirie@parrot.com> | 2016-03-09 21:05:49 +0300 |
|---|---|---|
| committer | Jonathan Cameron <jic23@kernel.org> | 2016-06-30 21:41:38 +0300 |
| commit | bc2b7dab629a51e8beb5fda4222c62a23b729f26 (patch) | |
| tree | 302108fe801299d98882e8d506b4415746408374 /drivers/iio/industrialio-event.c | |
| parent | eaaa7ec71bff4cb34d9025ed89068d4b3cac3df0 (diff) | |
| download | linux-bc2b7dab629a51e8beb5fda4222c62a23b729f26.tar.xz | |
iio:core: timestamping clock selection support
Adds a new per-device sysfs attribute "current_timestamp_clock" to allow
userspace to select a particular POSIX clock for buffered samples and
events timestamping.
Following clocks, as listed in clock_gettime(2), are supported:
CLOCK_REALTIME, CLOCK_MONOTONIC, CLOCK_MONOTONIC_RAW,
CLOCK_REALTIME_COARSE, CLOCK_MONOTONIC_COARSE, CLOCK_BOOTTIME and
CLOCK_TAI.
Signed-off-by: Gregor Boirie <gregor.boirie@parrot.com>
Acked-by: Sanchayan Maity <maitysanchayan@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Diffstat (limited to 'drivers/iio/industrialio-event.c')
| -rw-r--r-- | drivers/iio/industrialio-event.c | 19 |
1 files changed, 16 insertions, 3 deletions
diff --git a/drivers/iio/industrialio-event.c b/drivers/iio/industrialio-event.c index cae332b1d7ea..0ebfc923a997 100644 --- a/drivers/iio/industrialio-event.c +++ b/drivers/iio/industrialio-event.c @@ -44,6 +44,11 @@ struct iio_event_interface { struct mutex read_lock; }; +bool iio_event_enabled(const struct iio_event_interface *ev_int) +{ + return !!test_bit(IIO_BUSY_BIT_POS, &ev_int->flags); +} + /** * iio_push_event() - try to add event to the list for userspace reading * @indio_dev: IIO device structure @@ -60,7 +65,7 @@ int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp) int copied; /* Does anyone care? */ - if (test_bit(IIO_BUSY_BIT_POS, &ev_int->flags)) { + if (iio_event_enabled(ev_int)) { ev.id = ev_code; ev.timestamp = timestamp; @@ -180,8 +185,14 @@ int iio_event_getfd(struct iio_dev *indio_dev) if (ev_int == NULL) return -ENODEV; - if (test_and_set_bit(IIO_BUSY_BIT_POS, &ev_int->flags)) - return -EBUSY; + fd = mutex_lock_interruptible(&indio_dev->mlock); + if (fd) + return fd; + + if (test_and_set_bit(IIO_BUSY_BIT_POS, &ev_int->flags)) { + fd = -EBUSY; + goto unlock; + } iio_device_get(indio_dev); @@ -194,6 +205,8 @@ int iio_event_getfd(struct iio_dev *indio_dev) kfifo_reset_out(&ev_int->det_events); } +unlock: + mutex_unlock(&indio_dev->mlock); return fd; } |