[CCing Jesse, as I am talking about his patch] On Thu, 2013-10-10 at 19:04 -0700, Rusty Lynch wrote: > I went ahead and pulled in your kernel update into the release project > and now see that the display was once showing up as HDMI1 is now showing > up as HDMI2.
OK, this is because of the HDMI3 enabling patch: https://review.tizen.org/git/?p=profile/ivi/kernel-x86-ivi.git;a=commit;h=a18e6aeb05162a53b5f23a0eaba72e40884753fc Before this patch, the port register order was (simplified): DP HDMIB After this patch the order is: HDMIC DP HDMIB BB have only HDMIB connector, HDMIC is on the chip, but there is no connector. As you see, with this patch HDMIB is registered after HDMIC, which means that the dirver will name it "HDMI-2", while before this patch it was "HDMI-1". To put it differently, the numbering depends on the order the driver registers ports. > What causes this? See above. The registering order changed due to internal driver changes, the numbering changed too. > Is there anyone to ensure that the first HDMI device > found is always HDMI1 so that on a system with only one HDMI connector > we can be guaranteed that the output is HDMI1? No. The driver just registered all ports in _some_ order, without giving any order guarantees, so the numbering is arbitrary. It has always been the case. It even used to be that if you unload the i915 driver and load it again, you end up with different numbering. Nowadays it is not the case anymore, but nevertheless, the driver still does not give guarantees WRT port numbering. The problem is that we have static configuration in weston.ini, which assumes persistent port ordering, which is a false assumption. >From the console I can easily see that HDMI-1 has no display connected, while HDMI-2 does: $ cat /sys/class/drm/card0-HDMI-A-2/status connected $ cat /sys/class/drm/card0-HDMI-A-1/status disconnected I guess weston could do a similar thing? Anyway, if you believe that the kernel driver must preserve ordering, we need to discuss with Jesse. Specifically about his patch, I guess it could be amended to register HDMIB _first_. Thanks! -- Best Regards, Artem Bityutskiy --------------------------------------------------------------------- Intel Finland Oy Registered Address: PL 281, 00181 Helsinki Business Identity Code: 0357606 - 4 Domiciled in Helsinki This e-mail and any attachments may contain confidential material for the sole use of the intended recipient(s). Any review or distribution by others is strictly prohibited. If you are not the intended recipient, please contact the sender and delete all copies. _______________________________________________ IVI mailing list [email protected] https://lists.tizen.org/listinfo/ivi
