1 files changed, 22 insertions, 1 deletions

diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c
index 4dcc3a0f9930..c67d83bdc8f0 100644
--- a/drivers/iio/industrialio-buffer.c
+++ b/drivers/iio/industrialio-buffer.c
@@ -56,13 +56,34 @@ ssize_t iio_buffer_read_first_n_outer(struct file *filp, char __user *buf,
 {
         struct iio_dev *indio_dev = filp->private_data;
         struct iio_buffer *rb = indio_dev->buffer;
+        int ret;
 
         if (!indio_dev->info)
                 return -ENODEV;
 
         if (!rb || !rb->access->read_first_n)
                 return -EINVAL;
-        return rb->access->read_first_n(rb, n, buf);
+
+        do {
+                if (!iio_buffer_data_available(rb)) {
+                        if (filp->f_flags & O_NONBLOCK)
+                                return -EAGAIN;
+
+                        ret = wait_event_interruptible(rb->pollq,
+                                        iio_buffer_data_available(rb) ||
+                                        indio_dev->info == NULL);
+                        if (ret)
+                                return ret;
+                        if (indio_dev->info == NULL)
+                                return -ENODEV;
+                }
+
+                ret = rb->access->read_first_n(rb, n, buf);
+                if (ret == 0 && (filp->f_flags & O_NONBLOCK))
+                        ret = -EAGAIN;
+         } while (ret == 0);
+
+        return ret;
 }
 
 /**