iio: add enable and disable services to iio backend framework

Add iio_backend_disable() and iio_backend_enable() APIs to allow
IIO backend consumer to request backend disabling and enabling.
Signed-off-by: Olivier Moysan <olivier.moysan@foss.st.com>
Reviewed-by: Nuno Sa <nuno.sa@analog.com>
Link: https://patch.msgid.link/20240730084640.1307938-3-olivier.moysan@foss.st.comSigned-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/industrialio-backend.c

@@ -291,6 +291,29 @@ static void __iio_backend_disable(void *back)
 	iio_backend_void_op_call(back, disable);
 }
 
+/**
+ * iio_backend_disable - Backend disable
+ * @back: Backend device
+ */
+void iio_backend_disable(struct iio_backend *back)
+{
+	__iio_backend_disable(back);
+}
+EXPORT_SYMBOL_NS_GPL(iio_backend_disable, IIO_BACKEND);
+
+/**
+ * iio_backend_enable - Backend enable
+ * @back: Backend device
+ *
+ * RETURNS:
+ * 0 on success, negative error number on failure.
+ */
+int iio_backend_enable(struct iio_backend *back)
+{
+	return iio_backend_op_call(back, enable);
+}
+EXPORT_SYMBOL_NS_GPL(iio_backend_enable, IIO_BACKEND);
+
 /**
  * devm_iio_backend_enable - Device managed backend enable
  * @dev: Consumer device for the backend
@@ -303,7 +326,7 @@ int devm_iio_backend_enable(struct device *dev, struct iio_backend *back)
 {
 	int ret;
 
-	ret = iio_backend_op_call(back, enable);
+	ret = iio_backend_enable(back);
 	if (ret)
 		return ret;
 

include/linux/iio/backend.h

@@ -144,6 +144,8 @@ struct iio_backend_info {
 int iio_backend_chan_enable(struct iio_backend *back, unsigned int chan);
 int iio_backend_chan_disable(struct iio_backend *back, unsigned int chan);
 int devm_iio_backend_enable(struct device *dev, struct iio_backend *back);
+int iio_backend_enable(struct iio_backend *back);
+void iio_backend_disable(struct iio_backend *back);
 int iio_backend_data_format_set(struct iio_backend *back, unsigned int chan,
 				const struct iio_backend_data_fmt *data);
 int iio_backend_data_source_set(struct iio_backend *back, unsigned int chan,