Hello, On Fri, Oct 08, 2021 at 03:27:43PM +0200, Andrzej Hajda wrote: > Hi, > > Removed my invalid email (I will update files next week). > > On 08.10.2021 13:14, Jagan Teki wrote: > > Hi, > > > > I think this seems to be a known use case for industrial these days with i.mx8m. > > > > The host DSI would configure with two bridges one for DSI to LVDS > > (SN65DSI83) and another for DSI to HDMI Out (ADV7535). Technically we > > can use only one bridge at a time as host DSI support single out port. > > So we can have two separate device tree files for LVDS and HDMI and > > load them static. > > > > But, one of the use cases is to support both of them in single dts, and > > - Turn On LVDS (default) > > - Turn Off LVDS then Turn On HDMI when cable plug-in > > Are you sure it will work from hardware PoV? Do you have some demuxer? > isolation of pins? It may be in the category of "you shouldn't do this, but it actually works". I've seen the same being done with two CSI-2 camera sensors connected to the same receiver, with one of them being held in reset at all times. > > The HDMI event can be detected via some HDMI-INT GPIO on-board design. > > > > The possible solution, I'm thinking of adding LVDS on port 1, HDMI on > > port 2 in the DSI host node, and trying to attach the respective > > bridge based on HDMI-INT like repeating the bridge attachment cycle > > based on the HDMI-INT. > > I think more appropriate would be to share the same port, but provide > two endpoints inside this port - we have two hardware sharing the same > physical port. That sounds like the correct DT description to me. > > Can it be possible to do bridge attachment at runtime? something like > > a bridge hotplug event? or any other possible solutions? > > > > Any suggestions? > > Practically it is possible, see exynos_dsi + panels, or exynos_dsi + > some toshiba bridge - panel and bridge are dynamically 'plugged' and > 'unplugged' from exynos_drm, but they do not use bridge chain for this > and some other reasons. (un|re|)plugging should be performed of course > when pipeline is off (connector disconnected). I am not sure about > bridges added to bridge chain - you need to inspect all opses to ensure > it can be done safely. > > And the main issue: Daniel does not like it :) Neither do I :-) Could it be handled with two DRM connectors that are mutually exclusive ? -- Regards, Laurent Pinchart
