[PATCH 01/14] iio: backend: add support for filter config

[Antoniu Miclaus <antoniu.miclaus@xxxxxxxxxx>]

Add backend support for filter enable/disable.
This setting can be adjusted within the IP cores interfacing devices.

Signed-off-by: Antoniu Miclaus <antoniu.miclaus@xxxxxxxxxx>
---
 drivers/iio/industrialio-backend.c | 26 ++++++++++++++++++++++++++
 include/linux/iio/backend.h        |  6 ++++++
 2 files changed, 32 insertions(+)

diff --git a/drivers/iio/industrialio-backend.c b/drivers/iio/industrialio-backend.c
index d4ad36f54090..ffafe7c73508 100644
--- a/drivers/iio/industrialio-backend.c
+++ b/drivers/iio/industrialio-backend.c
@@ -778,6 +778,32 @@ static int __devm_iio_backend_get(struct device *dev, struct iio_backend *back)
 	return 0;
 }
 
+/**
+ * iio_backend_filter_enable - Enable filter
+ * @back: Backend device
+ *
+ * RETURNS:
+ * 0 on success, negative error number on failure.
+ */
+int iio_backend_filter_enable(struct iio_backend *back)
+{
+	return iio_backend_op_call(back, filter_enable);
+}
+EXPORT_SYMBOL_NS_GPL(iio_backend_filter_enable, "IIO_BACKEND");
+
+/**
+ * iio_backend_filter_disable - Disable filter
+ * @back: Backend device
+ *
+ * RETURNS:
+ * 0 on success, negative error number on failure.
+ */
+int iio_backend_filter_disable(struct iio_backend *back)
+{
+	return iio_backend_op_call(back, filter_disable);
+}
+EXPORT_SYMBOL_NS_GPL(iio_backend_filter_disable, "IIO_BACKEND");
+
 /**
  * iio_backend_ddr_enable - Enable interface DDR (Double Data Rate) mode
  * @back: Backend device
diff --git a/include/linux/iio/backend.h b/include/linux/iio/backend.h
index e45b7dfbec35..7987d9f1cdb3 100644
--- a/include/linux/iio/backend.h
+++ b/include/linux/iio/backend.h
@@ -100,6 +100,8 @@ enum iio_backend_interface_type {
  * @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.
+ * @filter_enable: Enable filter.
+ * @filter_disable: Disable filter.
  * @ddr_enable: Enable interface DDR (Double Data Rate) mode.
  * @ddr_disable: Disable interface DDR (Double Data Rate) mode.
  * @data_stream_enable: Enable data stream.
@@ -150,6 +152,8 @@ struct iio_backend_ops {
 					 size_t len);
 	int (*debugfs_reg_access)(struct iio_backend *back, unsigned int reg,
 				  unsigned int writeval, unsigned int *readval);
+	int (*filter_enable)(struct iio_backend *back);
+	int (*filter_disable)(struct iio_backend *back);
 	int (*ddr_enable)(struct iio_backend *back);
 	int (*ddr_disable)(struct iio_backend *back);
 	int (*data_stream_enable)(struct iio_backend *back);
@@ -190,6 +194,8 @@ int iio_backend_data_sample_trigger(struct iio_backend *back,
 int devm_iio_backend_request_buffer(struct device *dev,
 				    struct iio_backend *back,
 				    struct iio_dev *indio_dev);
+int iio_backend_filter_enable(struct iio_backend *back);
+int iio_backend_filter_disable(struct iio_backend *back);
 int iio_backend_ddr_enable(struct iio_backend *back);
 int iio_backend_ddr_disable(struct iio_backend *back);
 int iio_backend_data_stream_enable(struct iio_backend *back);
-- 
2.48.1