[PATCH v5 2/6] iio: backend: add support for data size set

Antoniu Miclaus
2024-11-01T11:24:43Z

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@analog.com>
---
no changes in v5.
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 c792cd1e24e8..6f4e38417dfd 100644
--- a/drivers/iio/industrialio-backend.c
+++ b/drivers/iio/industrialio-backend.c
@@ -660,6 +660,27 @@ 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
* @back: Backend device
diff --git a/include/linux/iio/backend.h b/include/linux/iio/backend.h
index e5ea90f1c3e0..83ca4f0124db 100644
--- a/include/linux/iio/backend.h
+++ b/include/linux/iio/backend.h
@@ -93,6 +93,7 @@ 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.
* @read_raw: Read a channel attribute from a backend device
* @debugfs_print_chan_status: Print channel status into a buffer.
* @debugfs_reg_access: Read or write register value of backend.
@@ -130,6 +131,7 @@ 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 (*read_raw)(struct iio_backend *back,
struct iio_chan_spec const *chan, int *val, int *val2,
long mask);
@@ -180,6 +182,7 @@ ssize_t iio_backend_ext_info_get(struct iio_dev *indio_dev, uintptr_t private,
const struct iio_chan_spec *chan, char *buf);
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_read_raw(struct iio_backend *back,
struct iio_chan_spec const *chan, int *val, int *val2,
long mask);
--
2.47.0