X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=drivers%2Fiio%2Findustrialio-buffer.c;h=32bb036069eb032313fa95895c83b3396cd752f3;hb=3363653512853754fcc7592d2c68c4769a4825c9;hp=d7e908acb48020b3f5390030e5a3687b03ba9878;hpb=30c44659f4a3e7e1f9f47e895591b4b40bf62671;p=firefly-linux-kernel-4.4.55.git

diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c
index d7e908acb480..32bb036069eb 100644
--- a/drivers/iio/industrialio-buffer.c
+++ b/drivers/iio/industrialio-buffer.c
@@ -107,9 +107,10 @@ 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;
+	DEFINE_WAIT_FUNC(wait, woken_wake_function);
 	size_t datum_size;
 	size_t to_wait;
-	int ret;
+	int ret = 0;
 
 	if (!indio_dev->info)
 		return -ENODEV;
@@ -131,19 +132,29 @@ ssize_t iio_buffer_read_first_n_outer(struct file *filp, char __user *buf,
 	else
 		to_wait = min_t(size_t, n / datum_size, rb->watermark);
 
+	add_wait_queue(&rb->pollq, &wait);
 	do {
-		ret = wait_event_interruptible(rb->pollq,
-		      iio_buffer_ready(indio_dev, rb, to_wait, n / datum_size));
-		if (ret)
-			return ret;
+		if (!indio_dev->info) {
+			ret = -ENODEV;
+			break;
+		}
 
-		if (!indio_dev->info)
-			return -ENODEV;
+		if (!iio_buffer_ready(indio_dev, rb, to_wait, n / datum_size)) {
+			if (signal_pending(current)) {
+				ret = -ERESTARTSYS;
+				break;
+			}
+
+			wait_woken(&wait, TASK_INTERRUPTIBLE,
+				   MAX_SCHEDULE_TIMEOUT);
+			continue;
+		}
 
 		ret = rb->access->read_first_n(rb, n, buf);
 		if (ret == 0 && (filp->f_flags & O_NONBLOCK))
 			ret = -EAGAIN;
-	 } while (ret == 0);
+	} while (ret == 0);
+	remove_wait_queue(&rb->pollq, &wait);
 
 	return ret;
 }
@@ -302,7 +313,7 @@ static int iio_scan_mask_set(struct iio_dev *indio_dev,
 	if (trialmask == NULL)
 		return -ENOMEM;
 	if (!indio_dev->masklength) {
-		WARN_ON("Trying to set scanmask prior to registering buffer\n");
+		WARN(1, "Trying to set scanmask prior to registering buffer\n");
 		goto err_invalid_mask;
 	}
 	bitmap_copy(trialmask, buffer->scan_mask, indio_dev->masklength);