iio: Specify supported modes for buffers
For each buffer type specify the supported device modes for this buffer.
This allows us for devices which support multiple different operating modes
to pick the correct operating mode based on the modes supported by the
attached buffers.
It also prevents that buffers with conflicting modes are attached
to a device at the same time or that a buffer with a non-supported mode is
attached to a device (e.g. in-kernel callback buffer to a device only
supporting hardware mode).
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c
index 209c7ad..0a14bd8 100644
--- a/drivers/iio/industrialio-buffer.c
+++ b/drivers/iio/industrialio-buffer.c
@@ -604,6 +604,7 @@
const unsigned long *scan_mask;
struct iio_buffer *buffer;
bool scan_timestamp;
+ unsigned int modes;
memset(config, 0, sizeof(*config));
@@ -615,12 +616,23 @@
list_is_singular(&indio_dev->buffer_list))
return 0;
+ modes = indio_dev->modes;
+
+ list_for_each_entry(buffer, &indio_dev->buffer_list, buffer_list) {
+ if (buffer == remove_buffer)
+ continue;
+ modes &= buffer->access->modes;
+ }
+
+ if (insert_buffer)
+ modes &= insert_buffer->access->modes;
+
/* Definitely possible for devices to support both of these. */
- if ((indio_dev->modes & INDIO_BUFFER_TRIGGERED) && indio_dev->trig) {
+ if ((modes & INDIO_BUFFER_TRIGGERED) && indio_dev->trig) {
config->mode = INDIO_BUFFER_TRIGGERED;
- } else if (indio_dev->modes & INDIO_BUFFER_HARDWARE) {
+ } else if (modes & INDIO_BUFFER_HARDWARE) {
config->mode = INDIO_BUFFER_HARDWARE;
- } else if (indio_dev->modes & INDIO_BUFFER_SOFTWARE) {
+ } else if (modes & INDIO_BUFFER_SOFTWARE) {
config->mode = INDIO_BUFFER_SOFTWARE;
} else {
/* Can only occur on first buffer */