Merge tag 'iio-fixes-for-3.12a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-linus

Jonathan writes:

First round of IIO fixes for 3.12

A series of wrong 'struct dev' assumptions in suspend/resume callbacks
following on from this issue being identified in a new driver review.
One to watch out for in future.

A number of driver specific fixes
1) at91 - fix a overflow in clock rate computation
2) dummy - Kconfig dependency issue
3) isl29018 - uninitialized value
4) hmc5843 - measurement conversion bug introduced by recent cleanup.
5) ade7854-spi - wrong return value.

Some IIO core fixes
1) Wrong value picked up for event code creation for a modified channel
2) A null dereference on failure to initialize a buffer after no buffer has
   been in use, when using the available_scan_masks approach.
3) Sampling not stopped when a device is removed. Effects forced removal
   such as hot unplugging.
4) Prevent device going away if a chrdev is still open in userspace.
5) Prevent race on chardev opening and device being freed.
6) Add a missing iio_buffer_init in the call back buffer.

These last few are the first part of a set from Lars-Peter Clausen who
has been taking a closer look at our removal paths and buffer handling
than anyone has for quite some time.

1 files changed, 28 insertions, 2 deletions

diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c
index e73033f3839..2710f7245c3 100644
--- a/drivers/iio/industrialio-buffer.c
+++ b/drivers/iio/industrialio-buffer.c
@@ -460,6 +460,25 @@ static int iio_compute_scan_bytes(struct iio_dev *indio_dev, const long *mask,
 	return bytes;
 }
 
+void iio_disable_all_buffers(struct iio_dev *indio_dev)
+{
+	struct iio_buffer *buffer, *_buffer;
+
+	if (list_empty(&indio_dev->buffer_list))
+		return;
+
+	if (indio_dev->setup_ops->predisable)
+		indio_dev->setup_ops->predisable(indio_dev);
+
+	list_for_each_entry_safe(buffer, _buffer,
+			&indio_dev->buffer_list, buffer_list)
+		list_del_init(&buffer->buffer_list);
+
+	indio_dev->currentmode = INDIO_DIRECT_MODE;
+	if (indio_dev->setup_ops->postdisable)
+		indio_dev->setup_ops->postdisable(indio_dev);
+}
+
 int iio_update_buffers(struct iio_dev *indio_dev,
 		       struct iio_buffer *insert_buffer,
 		       struct iio_buffer *remove_buffer)
@@ -528,8 +547,15 @@ int iio_update_buffers(struct iio_dev *indio_dev,
 			 * Note can only occur when adding a buffer.
 			 */
 			list_del(&insert_buffer->buffer_list);
-			indio_dev->active_scan_mask = old_mask;
-			success = -EINVAL;
+			if (old_mask) {
+				indio_dev->active_scan_mask = old_mask;
+				success = -EINVAL;
+			}
+			else {
+				kfree(compound_mask);
+				ret = -EINVAL;
+				goto error_ret;
+			}
 		}
 	} else {
 		indio_dev->active_scan_mask = compound_mask;