iio: backend: extend features

Extend backend features with new calls needed later on this
patchset from axi version of ad3552r.

The follwoing calls are added:

iio_backend_ddr_enable()
	enable ddr bus transfer
iio_backend_ddr_disable()
	disable ddr bus transfer
iio_backend_data_stream_enable()
	enable data stream over bus interface
iio_backend_data_stream_disable()
	disable data stream over bus interface
iio_backend_data_transfer_addr()
	define the target register address where the DAC sample
	will be written.

Reviewed-by: Nuno Sa <nuno.sa@analog.com>
Signed-off-by: Angelo Dureghello <adureghello@baylibre.com>
Reviewed-by: David Lechner <dlechner@baylibre.com>
Link: https://patch.msgid.link/20241028-wip-bl-ad3552r-axi-v0-iio-testing-v9-3-f6960b4f9719@kernel-space.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

1 files changed, 78 insertions, 0 deletions

diff --git a/drivers/iio/industrialio-backend.c b/drivers/iio/industrialio-backend.c
index 20b3b5212da7..81f3d24f0c50 100644
--- a/drivers/iio/industrialio-backend.c
+++ b/drivers/iio/industrialio-backend.c
@@ -718,6 +718,84 @@ static int __devm_iio_backend_get(struct device *dev, struct iio_backend *back)
 	return 0;
 }
 
+/**
+ * iio_backend_ddr_enable - Enable interface DDR (Double Data Rate) mode
+ * @back: Backend device
+ *
+ * Enable DDR, data is generated by the IP at each front (raising and falling)
+ * of the bus clock signal.
+ *
+ * RETURNS:
+ * 0 on success, negative error number on failure.
+ */
+int iio_backend_ddr_enable(struct iio_backend *back)
+{
+	return iio_backend_op_call(back, ddr_enable);
+}
+EXPORT_SYMBOL_NS_GPL(iio_backend_ddr_enable, IIO_BACKEND);
+
+/**
+ * iio_backend_ddr_disable - Disable interface DDR (Double Data Rate) mode
+ * @back: Backend device
+ *
+ * Disable DDR, setting into SDR mode (Single Data Rate).
+ *
+ * RETURNS:
+ * 0 on success, negative error number on failure.
+ */
+int iio_backend_ddr_disable(struct iio_backend *back)
+{
+	return iio_backend_op_call(back, ddr_disable);
+}
+EXPORT_SYMBOL_NS_GPL(iio_backend_ddr_disable, IIO_BACKEND);
+
+/**
+ * iio_backend_data_stream_enable - Enable data stream
+ * @back: Backend device
+ *
+ * Enable data stream over the bus interface.
+ *
+ * RETURNS:
+ * 0 on success, negative error number on failure.
+ */
+int iio_backend_data_stream_enable(struct iio_backend *back)
+{
+	return iio_backend_op_call(back, data_stream_enable);
+}
+EXPORT_SYMBOL_NS_GPL(iio_backend_data_stream_enable, IIO_BACKEND);
+
+/**
+ * iio_backend_data_stream_disable - Disable data stream
+ * @back: Backend device
+ *
+ * Disable data stream over the bus interface.
+ *
+ * RETURNS:
+ * 0 on success, negative error number on failure.
+ */
+int iio_backend_data_stream_disable(struct iio_backend *back)
+{
+	return iio_backend_op_call(back, data_stream_disable);
+}
+EXPORT_SYMBOL_NS_GPL(iio_backend_data_stream_disable, IIO_BACKEND);
+
+/**
+ * iio_backend_data_transfer_addr - Set data address.
+ * @back: Backend device
+ * @address: Data register address
+ *
+ * Some devices may need to inform the backend about an address
+ * where to read or write the data.
+ *
+ * RETURNS:
+ * 0 on success, negative error number on failure.
+ */
+int iio_backend_data_transfer_addr(struct iio_backend *back, u32 address)
+{
+	return iio_backend_op_call(back, data_transfer_addr, address);
+}
+EXPORT_SYMBOL_NS_GPL(iio_backend_data_transfer_addr, IIO_BACKEND);
+
 static struct iio_backend *__devm_iio_backend_fwnode_get(struct device *dev, const char *name,
 							 struct fwnode_handle *fwnode)
 {