| Message ID | 20240429190852.1008003-4-sakari.ailus@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Use V4L2 mbus config for conveying MEI CSI link frequency | expand |
Hi Sakari On Mon, Apr 29, 2024 at 10:08:51PM +0300, Sakari Ailus wrote: > Add the get_mbus_config() as the means for conveying the link frequency > towards the receiver drivers. > > Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> > --- > Documentation/driver-api/media/tx-rx.rst | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/Documentation/driver-api/media/tx-rx.rst b/Documentation/driver-api/media/tx-rx.rst > index 29d66a47b56e..2f22a1534da9 100644 > --- a/Documentation/driver-api/media/tx-rx.rst > +++ b/Documentation/driver-api/media/tx-rx.rst > @@ -49,6 +49,10 @@ Link frequency > The :ref:`V4L2_CID_LINK_FREQ <v4l2-cid-link-freq>` control is used to tell the > receiver the frequency of the bus (i.e. it is not the same as the symbol rate). > > +For devices where the link frequency is read-only, the link_freq field of struct A control can be 'read-only' as well. What about something along the lines of: For devices where the link frequency doesn't need to be exposed to userspace, the link_freq field of struct > +v4l2_mbus_config is recommended over controls for conveying the link frequency > +to the downstream driver in the pipeline. > + > ``.s_stream()`` callback > ^^^^^^^^^^^^^^^^^^^^^^^^ > > -- > 2.39.2 > >
Hi Jacopo, On Tue, Apr 30, 2024 at 09:23:52AM +0200, Jacopo Mondi wrote: > Hi Sakari > > On Mon, Apr 29, 2024 at 10:08:51PM +0300, Sakari Ailus wrote: > > Add the get_mbus_config() as the means for conveying the link frequency > > towards the receiver drivers. > > > > Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> > > --- > > Documentation/driver-api/media/tx-rx.rst | 4 ++++ > > 1 file changed, 4 insertions(+) > > > > diff --git a/Documentation/driver-api/media/tx-rx.rst b/Documentation/driver-api/media/tx-rx.rst > > index 29d66a47b56e..2f22a1534da9 100644 > > --- a/Documentation/driver-api/media/tx-rx.rst > > +++ b/Documentation/driver-api/media/tx-rx.rst > > @@ -49,6 +49,10 @@ Link frequency > > The :ref:`V4L2_CID_LINK_FREQ <v4l2-cid-link-freq>` control is used to tell the > > receiver the frequency of the bus (i.e. it is not the same as the symbol rate). > > > > +For devices where the link frequency is read-only, the link_freq field of struct > > A control can be 'read-only' as well. > > What about something along the lines of: > > For devices where the link frequency doesn't need to be exposed to userspace, > the link_freq field of struct I think we could use something like that. The LINK_FREQ control indeed allows choosing this from the user space but other than that it has little use AFAIU. > > > +v4l2_mbus_config is recommended over controls for conveying the link frequency > > +to the downstream driver in the pipeline. > > + > > ``.s_stream()`` callback > > ^^^^^^^^^^^^^^^^^^^^^^^^ > >
diff --git a/Documentation/driver-api/media/tx-rx.rst b/Documentation/driver-api/media/tx-rx.rst index 29d66a47b56e..2f22a1534da9 100644 --- a/Documentation/driver-api/media/tx-rx.rst +++ b/Documentation/driver-api/media/tx-rx.rst @@ -49,6 +49,10 @@ Link frequency The :ref:`V4L2_CID_LINK_FREQ <v4l2-cid-link-freq>` control is used to tell the receiver the frequency of the bus (i.e. it is not the same as the symbol rate). +For devices where the link frequency is read-only, the link_freq field of struct +v4l2_mbus_config is recommended over controls for conveying the link frequency +to the downstream driver in the pipeline. + ``.s_stream()`` callback ^^^^^^^^^^^^^^^^^^^^^^^^
Add the get_mbus_config() as the means for conveying the link frequency towards the receiver drivers. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> --- Documentation/driver-api/media/tx-rx.rst | 4 ++++ 1 file changed, 4 insertions(+)