Merge tag 'staging-3.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

Pull staging driver tree changes from Greg KH:
 "Here's the big drivers/staging/ update for 3.14-rc1

  Lots and lots of cleanups, IIO driver updates are also mixed in here
  due to the subsystem still crossing staging and drivers/iio/, and the
  dwc2 driver is moved out of staging.  There's a new driver (rts5208),
  which ends up making us adding more lines than removing, but overall
  there was lots of work toward moving code out of here, which was good

  All of this has been in linux-next with no reported issues"

* tag 'staging-3.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (1084 commits)
  lustre: delete linux/lustre_debug.h
  staging: lustre: remove some unused debug macros
  usb: dwc2: move device tree bindings doc to correct place
  staging: vt6656: sparse fixes: iwctl_giwgenie use memcpy.
  staging: vt6656: sparse fixes: iwctl_siwgenie use memcpy.
  staging: vt6656: sparse fixes ethtool_ioctl Use struct ifreq *
  staging: vt6656: sparse fixes: dpc.c missing dpc.h
  staging: lustre: libcfs_debug: small whitespace cleanups
  staging: lustre: libcfs_debug.h: remove extra blank lines
  staging: lustre: libcfs_debug.h: Align backslashes in macros
  staging: lustre: libcfs_debug.h: align define values
  staging: tidspbridge: adjust error return code (bugfix)
  Staging: rts5139: rts51x_card: fixed style issues
  staging: wlags49_h2: Fix "do not use C99 //" in wl_cs.h, wl_enc.h wl_main.h and wl_wext.h
  Staging: rtl8188eu: Fixed "foo * bar" related coding style issues
  Staging: rtl8188eu: Fixed required spaces after ',' and around '=' and '=='
  staging: vt6655: Fix memory leak in wpa_ioctl()
  imx-drm: parallel-display: honor 'native-mode' property when selecting video mode from DT
  staging: drm/imx: don't drop crtc offsets when doing pageflip
  staging: drm/imx: handle framebuffer offsets correctly
  ...

1 files changed, 14 insertions, 9 deletions

diff --git a/drivers/iio/kfifo_buf.c b/drivers/iio/kfifo_buf.c
index 95c6fc81c2c7..7134e8ada09a 100644
--- a/drivers/iio/kfifo_buf.c
+++ b/drivers/iio/kfifo_buf.c
@@ -42,7 +42,6 @@ static int iio_request_update_kfifo(struct iio_buffer *r)
 	} else {
 		kfifo_reset_out(&buf->kf);
 	}
-	r->stufftoread = false;
 	mutex_unlock(&buf->user_lock);
 
 	return ret;
@@ -108,7 +107,7 @@ static int iio_store_to_kfifo(struct iio_buffer *r,
 	ret = kfifo_in(&kf->kf, data, 1);
 	if (ret != 1)
 		return -EBUSY;
-	r->stufftoread = true;
+
 	wake_up_interruptible_poll(&r->pollq, POLLIN | POLLRDNORM);
 
 	return 0;
@@ -127,13 +126,6 @@ static int iio_read_first_n_kfifo(struct iio_buffer *r,
 		ret = -EINVAL;
 	else
 		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;
-
 	mutex_unlock(&kf->user_lock);
 	if (ret < 0)
 		return ret;
@@ -141,6 +133,18 @@ static int iio_read_first_n_kfifo(struct iio_buffer *r,
 	return copied;
 }
 
+static bool iio_kfifo_buf_data_available(struct iio_buffer *r)
+{
+	struct iio_kfifo *kf = iio_to_kfifo(r);
+	bool empty;
+
+	mutex_lock(&kf->user_lock);
+	empty = kfifo_is_empty(&kf->kf);
+	mutex_unlock(&kf->user_lock);
+
+	return !empty;
+}
+
 static void iio_kfifo_buffer_release(struct iio_buffer *buffer)
 {
 	struct iio_kfifo *kf = iio_to_kfifo(buffer);
@@ -153,6 +157,7 @@ static void iio_kfifo_buffer_release(struct iio_buffer *buffer)
 static const struct iio_buffer_access_funcs kfifo_access_funcs = {
 	.store_to = &iio_store_to_kfifo,
 	.read_first_n = &iio_read_first_n_kfifo,
+	.data_available = iio_kfifo_buf_data_available,
 	.request_update = &iio_request_update_kfifo,
 	.get_bytes_per_datum = &iio_get_bytes_per_datum_kfifo,
 	.set_bytes_per_datum = &iio_set_bytes_per_datum_kfifo,