On Fri, 2019-05-10 at 09:56 +0200, Daniel Vetter wrote: > On Fri, May 10, 2019 at 9:42 AM Paul Kocialkowski > <paul.kocialkowski@xxxxxxxxxxx> wrote: > > Hi, > > > > So this thread has drifted off from IGT to a general DRM improvement, > > so renaming the thread and adding some CCs. > > > > It's about avoiding full reprobes (which may include slow EDID reads, > > etc) when a connector change was detected, by providing information > > about the connector and the new state to userspace. This way, userspace > > can reprobe the changed connector alone (or not reprobe at all in case > > of a disconnect). > > > > It feels like there is growing temptation to have per-driver hacks to > > avoid full reprobes when the driver knows that nothing changed, but I > > think it makes more sense to fixup the uevent we send to make sure that > > userspace knows what to probe exactly. > > > > On Fri, 2019-05-10 at 06:55 +0000, Ser, Simon wrote: > > > On Thu, 2019-05-09 at 11:56 -0400, Lyude Paul wrote: > > > > I'm in support of this as well, we really could use better hotplug events. > > > > Feel free to cc patches to me for review :) > > > > > > Any idea(s) how the API would look like? > > > > From a quick chat on IRC yesterday, it seems that just adding entries > > to the uevent would do and would be backwards-compatible (well, > > provided that the userspace uevent parsers will not fail if something > > extra to "HOTPLUG=1" is provided). > > > > Currently, the notification is sent globally at each round of detected > > connector change (which may concern multiple connectors). So I think we > > should just list the connectors that changed in the uevent and their > > new state. So my proposal here is something like: > > > > HOTPLUG=1 > > CONNECTOR_ID=47 > > STATUS=Connected > > CONNECTOR_ID=48 > > STATUS=Disconnected > > > > Where each STATUS entry would refer to the previous CONNECTOR_ID entry. > > > > What do you think? > > We have the better uevent already, all we need is wiring up, lots of > code, and userspace for it. Ok, not quite, patch is still in flight: > > https://patchwork.kernel.org/patch/10906677/ Excellent. I can help with a userspace implementation if needed. _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
