* Re: [PATCH] KFiFO : Poll support
[not found] <1346089129-839-1-git-send-email-srinivas.pandruvada@intel.com>
@ 2012-08-27 17:53 ` Jonathan Cameron
0 siblings, 0 replies; only message in thread
From: Jonathan Cameron @ 2012-08-27 17:53 UTC (permalink / raw)
To: srinivas pandruvada; +Cc: linux-iio
On 08/27/2012 06:38 PM, srinivas pandruvada wrote:
> From: Jonathan Cameron <jic23@kernel.org>
>
> Implements poll system call support on IIO Kfifo buffers.
>
> Acked-by: srinivas pandruvada <srinivas.pandruvada@intel.com>
*laughs*
Delights of crossing emails. Thanks this got to me before I pushed so
have added it :)
> ---
> 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;
> }
>
^ permalink raw reply [flat|nested] only message in thread