staging:iio: Disallow changing scan elements in all buffered modes

Currently we only disallow changing the scan elements, while the buffer is
enabled, in triggered buffer mode. This patch changes it to disallow it for all
buffered modes. Disabling or enabling scan elements while the buffer is enabled
will cause undefined behavior since the reader will not be able to tell samples
with the new and old scan element set apart and thus wont be able to extract
any meaningful data from the buffer.

Acked-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/staging/iio/industrialio-buffer.c b/drivers/staging/iio/industrialio-buffer.c
index 36993038b2618d61ec83f9d26b19be0c6dcda92a..747b9013a6661e5f57264621d0c5476b08e59886 100644 (file)
--- a/drivers/staging/iio/industrialio-buffer.c
+++ b/drivers/staging/iio/industrialio-buffer.c
@@ -153,7 +153,7 @@ static ssize_t iio_scan_el_store(struct device *dev,
 
        state = !(buf[0] == '0');
        mutex_lock(&indio_dev->mlock);
-       if (indio_dev->currentmode == INDIO_BUFFER_TRIGGERED) {
+       if (iio_buffer_enabled(indio_dev)) {
                ret = -EBUSY;
                goto error_ret;
        }
@@ -196,7 +196,7 @@ static ssize_t iio_scan_el_ts_store(struct device *dev,
 
        state = !(buf[0] == '0');
        mutex_lock(&indio_dev->mlock);
-       if (indio_dev->currentmode == INDIO_BUFFER_TRIGGERED) {
+       if (iio_buffer_enabled(indio_dev)) {
                ret = -EBUSY;
                goto error_ret;
        }