iio: backend: add support for data size set

Add backend support for setting the data size used.
This setting can be adjusted within the IP cores interfacing devices.

Reviewed-by: Nuno Sa <nuno.sa@analog.com>
Reviewed-by: David Lechner <dlechner@baylibre.com>
Signed-off-by: Antoniu Miclaus <antoniu.miclaus@analog.com>
Link: https://patch.msgid.link/20250214131955.31973-3-antoniu.miclaus@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/industrialio-backend.c b/drivers/iio/industrialio-backend.c
index 8bf3d570da1b724b54e27590b972647e67242692..2088afa7a55ce473449e04de1758f67148bd40d7 100644 (file)
--- 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.
+ */
+int iio_backend_data_size_set(struct iio_backend *back, unsigned int 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 a0ea6c29d7bab230f472392d3e74cfacf73e2e03..9ae861a21472882c88aecec765a690ff86edab63 100644 (file)
--- a/include/linux/iio/backend.h
+++ b/include/linux/iio/backend.h
@@ -95,6 +95,7 @@ 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.
@@ -137,6 +138,7 @@ 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, unsigned int size);
        int (*read_raw)(struct iio_backend *back,
                        struct iio_chan_spec const *chan, int *val, int *val2,
                        long mask);
@@ -197,6 +199,7 @@ 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);
+int iio_backend_data_size_set(struct iio_backend *back, unsigned int size);
 int iio_backend_read_raw(struct iio_backend *back,
                         struct iio_chan_spec const *chan, int *val, int *val2,
                         long mask);