On Mon, Sep 23, 2024 at 12:15 PM Antoniu Miclaus <antoniu.miclaus@xxxxxxxxxx> wrote: > > Add backend support for obtaining the interface type used. > > Signed-off-by: Antoniu Miclaus <antoniu.miclaus@xxxxxxxxxx> > --- > drivers/iio/industrialio-backend.c | 24 ++++++++++++++++++++++++ > include/linux/iio/backend.h | 10 ++++++++++ > 2 files changed, 34 insertions(+) > > diff --git a/drivers/iio/industrialio-backend.c b/drivers/iio/industrialio-backend.c > index efe05be284b6..53ab6bc86a50 100644 > --- a/drivers/iio/industrialio-backend.c > +++ b/drivers/iio/industrialio-backend.c > @@ -449,6 +449,30 @@ ssize_t iio_backend_ext_info_set(struct iio_dev *indio_dev, uintptr_t private, > } > EXPORT_SYMBOL_NS_GPL(iio_backend_ext_info_set, IIO_BACKEND); > > +/** > + * iio_backend_interface_type_get - get the interace type used. > + * @back: Backend device > + * @type: Interface type > + * > + * RETURNS: > + * 0 on success, negative error number on failure. > + */ > +int iio_backend_interface_type_get(struct iio_backend *back, > + enum iio_backend_interface_type *type) > +{ > + int ret; > + > + ret = iio_backend_op_call(back, interface_type_get, type); > + if (ret) > + return ret; > + > + if (*type > IIO_BACKEND_INTERFACE_CMOS) > + return -EINVAL; > + > + return 0; > +} > +EXPORT_SYMBOL_NS_GPL(iio_backend_interface_type_get, IIO_BACKEND); > + > /** > * iio_backend_extend_chan_spec - Extend an IIO channel > * @indio_dev: IIO device > diff --git a/include/linux/iio/backend.h b/include/linux/iio/backend.h > index 8099759d7242..ba8ad30ac9ba 100644 > --- a/include/linux/iio/backend.h > +++ b/include/linux/iio/backend.h > @@ -63,6 +63,11 @@ enum iio_backend_sample_trigger { > IIO_BACKEND_SAMPLE_TRIGGER_MAX > }; > > +enum iio_backend_interface_type { > + IIO_BACKEND_INTERFACE_LVDS, > + IIO_BACKEND_INTERFACE_CMOS > +}; > + > /** > * struct iio_backend_ops - operations structure for an iio_backend > * @enable: Enable backend. > @@ -81,6 +86,7 @@ enum iio_backend_sample_trigger { > * @extend_chan_spec: Extend an IIO channel. > * @ext_info_set: Extended info setter. > * @ext_info_get: Extended info getter. > + * @interface_type_get: Interface type. > **/ > struct iio_backend_ops { > int (*enable)(struct iio_backend *back); > @@ -113,6 +119,8 @@ struct iio_backend_ops { > const char *buf, size_t len); > int (*ext_info_get)(struct iio_backend *back, uintptr_t private, > const struct iio_chan_spec *chan, char *buf); > + int (*interface_type_get)(struct iio_backend *back, > + enum iio_backend_interface_type *type); > }; > > int iio_backend_chan_enable(struct iio_backend *back, unsigned int chan); > @@ -142,6 +150,8 @@ ssize_t iio_backend_ext_info_set(struct iio_dev *indio_dev, uintptr_t private, > 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_extend_chan_spec(struct iio_dev *indio_dev, > struct iio_backend *back, > struct iio_chan_spec *chan); > -- > 2.46.0 > This seems very specific to the AD485x chips and the AXI ADC backend. Since it is describing how the chip is wired to the AXI DAC IP block, I would be tempted to use the devicetree for this info instead of adding a new backend function.