On Wed, Mar 30, 2022 at 2:22 PM Maxime Ripard <maxime@xxxxxxxxxx> wrote: > > On Tue, Mar 29, 2022 at 11:38:32PM +0530, Jagan Teki wrote: > > Hi all, > > > > I have implemented runtime display switching in the MIPI switch design > > where LVDS and HDMI bridges are selected with the help of runtime > > GPIO. > > > > Initial discussion on the same can be found here, > > https://www.spinics.net/lists/dri-devel/msg318524.html > > > > The implementation has been done by creating each connector at > > runtime. The default boot will create the LVDS connector and based on > > the HDMI plug-in the ISR. > > > > 1. forcing the LVDS to disconnect > > 2. call drm_kms_helper_hotplug_event > > 3. detach the bridge chain > > 4. attach the new bridge chain (HDMI) > > 5. call drm_kms_helper_hotplug_event > > > > do the reverse when we unplug the HDMI cable. > > > > So, the bridge chains are attached and detached based on GPIO > > Interrupt which is indeed identified based on the physical HDMIA > > connector. > > > > Pipeline for LVDS, > > mxfsb => nwl-dsi => display-switch => sn65dsi83=> panel-bridge > > > > Pipeline for HDMI, > > mxfsb => nwl-dsi => display-switch => adv7511 => display-connector > > > > With this, implementation and I can able switch the displays with > > default DRM (without specific DRM applications) where the LVDS is ON > > by default and when HDMI plug-in the LVDS OFF/HDMI ON, and when HDMI > > unplug the HDMI OFF/LVDS ON. > > > > However, with QT5 I can see the DRM Master ignoring hotplug event by > > returning 0 on drm_master_internal_acquire in > > drm_fb_helper_hotplug_event. With this the hotplug returned early so > > it cannot able to disconnect and connect the new switching connector. > > > > Any help? > > I'm not sure why you started another discussion with pretty much the > same content, but you can't rely on userspace handling the hotplug > event. You'll have to deal with the case where it just doesn't. I've added clear details here - thought that it reaches more people. Okay, I will continue on the old thread. Jagan.
