From: Jonathan Cameron <jic23@xxxxxxxxxx>
Implements poll system call support on IIO Kfifo buffers.
Acked-by: srinivas pandruvada <srinivas.pandruvada@xxxxxxxxx>
---
drivers/iio/kfifo_buf.c | 9 +++++++++
1 files changed, 9 insertions(+), 0 deletions(-)
diff --git a/drivers/iio/kfifo_buf.c b/drivers/iio/kfifo_buf.c
index 6bf9d05..e8033a4 100644
--- a/drivers/iio/kfifo_buf.c
+++ b/drivers/iio/kfifo_buf.c
@@ -6,6 +6,7 @@
#include <linux/kfifo.h>
#include <linux/mutex.h>
#include <linux/iio/kfifo_buf.h>
+#include <linux/sched.h>
struct iio_kfifo {
struct iio_buffer buffer;
@@ -35,6 +36,7 @@ static int iio_request_update_kfifo(struct iio_buffer *r)
kfifo_free(&buf->kf);
ret = __iio_allocate_kfifo(buf, buf->buffer.bytes_per_datum,
buf->buffer.length);
+ r->stufftoread = false;
error_ret:
return ret;
}
@@ -97,6 +99,8 @@ static int iio_store_to_kfifo(struct iio_buffer *r,
ret = kfifo_in(&kf->kf, data, r->bytes_per_datum);
if (ret != r->bytes_per_datum)
return -EBUSY;
+ r->stufftoread = true;
+ wake_up_interruptible(&r->pollq);
return 0;
}
@@ -111,6 +115,11 @@ static int iio_read_first_n_kfifo(struct iio_buffer *r,
n = rounddown(n, r->bytes_per_datum);
ret = kfifo_to_user(&kf->kf, buf, n, &copied);
+ if (kfifo_is_empty(&kf->kf))
+ r->stufftoread = false;
+ /* verify it is still empty to avoid race */
+ if (!kfifo_is_empty(&kf->kf))
+ r->stufftoread = true;
return copied;
}
--
1.7.7.6
--
To unsubscribe from this list: send the line "unsubscribe linux-iio" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
