Hi Andrzej, On Fri, Oct 8, 2021 at 6:57 PM Andrzej Hajda <andrzej.hajda@xxxxxxxxx> 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? Correct. I have noticed after you mentioned this. Design has two 2:1 MIPI Switch PI3WVR626 [1] which take 2 data-lanes and clock from Host and produce 4 data-lane and 1 clock to connect to ADV7535 and SN65DSI84 bridges. The switch has OE, SEL pins to select the desired to MUXed lanes/clock routing to an appropriate bridge. > > > > > 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. Make sense to me. I think we can in-corporate the MIPI Switch on the pipeline as input data and clock lanes are muxing. not sure how it can be done. > > > > > 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. I will check with this. However i did tried of hot-plug mechanism for bridge in exiting DSI host sun6i_mipi_dsi.c [2] look like it surely not possible with bridge-chain as hot-plug require drm pointer where the same pointer is not available during attach call. > > And the main issue: Daniel does not like it :) [1] https://www.diodes.com/assets/Datasheets/PI3WVR626.pdf [2] https://elixir.bootlin.com/linux/v5.15-rc4/source/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c#L976 Jagan.
