On Thursday 01 Dec 2016 12:30:09 Jean-Francois Moine wrote: > On Thu, 01 Dec 2016 12:41:20 +0200 Laurent Pinchart wrote: > >>> If a DVI connector instead of a HDMI connector is soldered, how > >>> should such a device tree be written? > >> > >> Use a dvi-connector instead :) > > > > The HDMI encoder DT node doesn't (and certainly shouldn't) report what > > type of connector is mounted on the board. Having a connector node in DT > > makes the connector type available to the system, allowing the DRM driver > > to expose the right connector type to userspace (it would be confusing > > for the user to report DRM_MODE_CONNECTOR_HDMIA for a DVI connector). > > The connector type, HDMI or DVI, is known by the EDID. > The user is not interested by the software indication of the connector > type: (s)he knows it because (s)he connected him/herself the display > device.
That's not correct. The connector type reported by DRM to userspace can be used as a hint to information the user about connectors. Displaying a "Please connect a monitor to the HDMI connector" is confusing when the system has a DVI connector. > And the DRM driver does not do anything from the knowledge of the > connector type in the DT. Only the EDID may tell if the display device > may do audio streaming (direct HDMI with audio capability) or not > (direct HDMI without audio, HDMI to DVI cable, DVI physical connector). -- Regards, Laurent Pinchart
