Hi Macro, On Fri, Mar 01, 2019 at 11:52:35AM +0100, Marco Felsch wrote: > Hi Sakari, > > On 19-02-18 12:03, Sakari Ailus wrote: > > Hi Marco, > > > > My apologies for reviewing this so late. You've received good comments > > already. I have a few more. > > Thanks for your review for the other patches as well =) Sorry for my > delayed response. > > > On Tue, Dec 18, 2018 at 03:12:38PM +0100, Marco Felsch wrote: > > > Add corresponding dt-bindings for the Toshiba tc358746 device. > > > > > > Signed-off-by: Marco Felsch <m.felsch@xxxxxxxxxxxxxx> > > > --- > > > .../bindings/media/i2c/toshiba,tc358746.txt | 80 +++++++++++++++++++ > > > 1 file changed, 80 insertions(+) > > > create mode 100644 Documentation/devicetree/bindings/media/i2c/toshiba,tc358746.txt > > > > > > diff --git a/Documentation/devicetree/bindings/media/i2c/toshiba,tc358746.txt b/Documentation/devicetree/bindings/media/i2c/toshiba,tc358746.txt > > > new file mode 100644 > > > index 000000000000..499733df744a > > > --- /dev/null > > > +++ b/Documentation/devicetree/bindings/media/i2c/toshiba,tc358746.txt > > > @@ -0,0 +1,80 @@ > > > +* Toshiba TC358746 Parallel to MIPI CSI2-TX or MIPI CSI2-RX to Parallel Bridge > > > + > > > +The Toshiba TC358746 is a bridge that converts a Parallel-in stream to MIPI CSI-2 TX > > > +or a MIPI CSI-2 RX stream into a Parallel-out. It is programmable through I2C. > > > > This is interesting. The driver somehow needs to figure out the direction > > of the data flow if it does not originate from DT. I guess it shouldn't as > > it's not the property of an individual device, albeit in practice in all > > hardware I've seen the direction of the pipeline is determinable and this > > is visible in the kAPI as well. So I'm suggesting no changes due to this in > > bindings, likely we'll need to address it somehow elsewhere going forward. > > What did you mean with "... and this is visible in the kAPI as well"? > I'm relative new in the linux-media world but I never saw a device which > supports two directions. Our customer which uses that chip use it > only in parallel-in/csi-out mode. To be flexible the switching should be > done by a subdev-ioctl but it is also reasonable to define a default value > within the DT. What I meant that the V4L2 sub-device API does not provide any information on the direction. It is implicit --- MC does, but it does it based on the links created by the driver. I agree a DT property would be a good way to tell this, especially now that there's a related hardware configuration (but which the software cannot obtain directly). -- Regards, Sakari Ailus sakari.ailus@xxxxxxxxxxxxxxx
