diff options
| author | Lars-Peter Clausen <lars@metafoo.de> | 2012-01-03 14:59:41 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-02-09 10:05:06 -0800 |
| commit | e18045ed75ec682a26a385b0072dcc030fd12a7e (patch) | |
| tree | b8c95b13d9a9b295d64acba66c38f4952871d889 | |
| parent | 43ba1100af11f34cc67bdf6b359667cfa851e6a8 (diff) | |
staging:iio:events: Add poll support
Add poll support to the event queue. This will allow us to check for pending
events in a application's event loop using poll() or similar. Since we already
have support for blocking reads adding poll support as well is trivial.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/staging/iio/industrialio-event.c | 23 |
1 files changed, 22 insertions, 1 deletions
diff --git a/drivers/staging/iio/industrialio-event.c b/drivers/staging/iio/industrialio-event.c index f0c41f1f505a..800f67d4cce1 100644 --- a/drivers/staging/iio/industrialio-event.c +++ b/drivers/staging/iio/industrialio-event.c @@ -15,6 +15,7 @@ #include <linux/kernel.h> #include <linux/kfifo.h> #include <linux/module.h> +#include <linux/poll.h> #include <linux/sched.h> #include <linux/slab.h> #include <linux/uaccess.h> @@ -57,7 +58,7 @@ int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp) copied = kfifo_put(&ev_int->det_events, &ev); if (copied != 0) - wake_up_locked(&ev_int->wait); + wake_up_locked_poll(&ev_int->wait, POLLIN); } spin_unlock(&ev_int->wait.lock); @@ -65,6 +66,25 @@ int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp) } EXPORT_SYMBOL(iio_push_event); +/** + * iio_event_poll() - poll the event queue to find out if it has data + */ +static unsigned int iio_event_poll(struct file *filep, + struct poll_table_struct *wait) +{ + struct iio_event_interface *ev_int = filep->private_data; + unsigned int events = 0; + + poll_wait(filep, &ev_int->wait, wait); + + spin_lock(&ev_int->wait.lock); + if (!kfifo_is_empty(&ev_int->det_events)) + events = POLLIN | POLLRDNORM; + spin_unlock(&ev_int->wait.lock); + + return events; +} + static ssize_t iio_event_chrdev_read(struct file *filep, char __user *buf, size_t count, @@ -118,6 +138,7 @@ static int iio_event_chrdev_release(struct inode *inode, struct file *filep) static const struct file_operations iio_event_chrdev_fileops = { .read = iio_event_chrdev_read, + .poll = iio_event_poll, .release = iio_event_chrdev_release, .owner = THIS_MODULE, .llseek = noop_llseek, |