Add backend support for setting the data size used.
This setting can be adjusted within the IP cores interfacing devices.
Signed-off-by: Antoniu Miclaus <antoniu.miclaus@xxxxxxxxxx>
---
changes in v2:
- use Return: instead of RETURN.
- use size_t instead of ssize_t
- improve commit message.
drivers/iio/industrialio-backend.c | 21 +++++++++++++++++++++
include/linux/iio/backend.h | 3 +++
2 files changed, 24 insertions(+)
diff --git a/drivers/iio/industrialio-backend.c b/drivers/iio/industrialio-backend.c
index a322b0be7b2c..9aaa90ed1274 100644
--- a/drivers/iio/industrialio-backend.c
+++ b/drivers/iio/industrialio-backend.c
@@ -473,6 +473,27 @@ int iio_backend_interface_type_get(struct iio_backend *back,
}
EXPORT_SYMBOL_NS_GPL(iio_backend_interface_type_get, IIO_BACKEND);
+/**
+ * iio_backend_data_size_set - set the data width/size in the data bus.
+ * @back: Backend device
+ * @size: Size in bits
+ *
+ * Some frontend devices can dynamically control the word/data size on the
+ * interface/data bus. Hence, the backend device needs to be aware of it so
+ * data can be correctly transferred.
+ *
+ * Return:
+ * 0 on success, negative error number on failure.
+ */
+size_t iio_backend_data_size_set(struct iio_backend *back, size_t size)
+{
+ if (!size)
+ return -EINVAL;
+
+ return iio_backend_op_call(back, data_size_set, size);
+}
+EXPORT_SYMBOL_NS_GPL(iio_backend_data_size_set, IIO_BACKEND);
+
/**
* iio_backend_extend_chan_spec - Extend an IIO channel
* @indio_dev: IIO device
diff --git a/include/linux/iio/backend.h b/include/linux/iio/backend.h
index 34fc76c99d8a..18e571a24251 100644
--- a/include/linux/iio/backend.h
+++ b/include/linux/iio/backend.h
@@ -88,6 +88,7 @@ enum iio_backend_interface_type {
* @ext_info_set: Extended info setter.
* @ext_info_get: Extended info getter.
* @interface_type_get: Interface type.
+ * @data_size_set: Data size.
**/
struct iio_backend_ops {
int (*enable)(struct iio_backend *back);
@@ -122,6 +123,7 @@ struct iio_backend_ops {
const struct iio_chan_spec *chan, char *buf);
int (*interface_type_get)(struct iio_backend *back,
enum iio_backend_interface_type *type);
+ int (*data_size_set)(struct iio_backend *back, ssize_t size);
};
int iio_backend_chan_enable(struct iio_backend *back, unsigned int chan);
@@ -153,6 +155,7 @@ ssize_t iio_backend_ext_info_get(struct iio_dev *indio_dev, uintptr_t private,
int iio_backend_interface_type_get(struct iio_backend *back,
enum iio_backend_interface_type *type);
+size_t iio_backend_data_size_set(struct iio_backend *back, size_t size);
int iio_backend_extend_chan_spec(struct iio_dev *indio_dev,
struct iio_backend *back,
struct iio_chan_spec *chan);
--
2.46.2
