Bug 71083

Summary:	(struct drm_encoder_helper_funcs)->mode_set not re-called after display (and EDID) change
Product:	DRI	Reporter:	Rafał Miłecki <zajec5>
Component:	DRM/other	Assignee:	Default DRI bug account <dri-devel>
Status:	RESOLVED INVALID	QA Contact:
Severity:	normal
Priority:	medium
Version:	unspecified
Hardware:	Other
OS:	All
Whiteboard:
i915 platform:		i915 features:

Description Rafał Miłecki 2013-10-31 10:34:13 UTC

I use my DCE5 Barts (HD69xx) with AV-receiver Onkyo TX-SR605 and one of the following displays:
1) TV Sony Bravia KDL-52X3500
2) Projector Epson EH-TW6100

My problem is that when I change display connected to the Onkyo's output EDID changes, but drm doesn't call mode_set as long as I use the same resolution.

To force drm to call mode_set I've to change resolution (xrandr --output HDMI-0 --mode X) and then swtich back to the mode I want.

While the display seems to be working fine without that mode_set call, the audio engine doesn't. As part of the modesetting handler we read ELD-related info from EDID and write it to the audio engine of the GPU. Without this happening I can't play correctly audio (because also sees info about previous device, not the current one).

I think mode_set should be called every time EDID changes. Is that right?

In case someone's curious:

1) EDID with Onkyo + Sony TV:
00ffffffffffff003dcb610700000000
0011010380a05a780a0dc9a057479827
12484c21080081800101010101010101
010101010101023a801871382d40582c
450040846300001e011d007251d01e20
6e28550040846300001e000000fc0054
582d53523630350a20202020000000fd
00303e0e460f000a2020202020200185
02034c705c1f03041213051420071610
15110206010f1e0b1a191d0e0a242625
2335097f070f7f071707503f06c05706
005f7e01671e00834f00006c030c0012
00b82dc000000000e3050301023a80d0
72382d40102c458040846300001e011d
00bc52d01e20b828554040846300001e
00000000000000000000000000000078

2) EDID with Onkyo + Epson projector:
00ffffffffffff004ca333d000000000
0c150104952616780aa0558d515a962a
1c505400000001010101010101010101
0101010101016a4d80a07038fc413020
36007ed710000018d49a80a07038fc41
302036007ed710000038000000fc0053
414d53554e470a2020202020000000fc
00313733485430322d4330310a200035

Comment 1 Alex Deucher 2013-10-31 13:17:40 UTC

Are you unplugging the cable from the card when you switch the monitors?  That should generate a hotplug event which will trigger the graphics stack to reprobe the displays.  If you are just changing the monitor connected to the receiver, it sounds like the receiver never sends a hotplug event to the card.  As such the card has no way of knowing that the EDID has changed.

Comment 2 Rafał Miłecki 2013-10-31 13:42:18 UTC

I do! I unplug HDMI that is between notebook and Onkyo and then start switching operation. I also get a notification about changed display configuration in KDE, so I'm sure events are generate correctly.

Comment 3 Martin Peres 2019-10-14 13:20:22 UTC

Hi,

Freedesktop's Bugzilla instance is EOLed and open bugs are about to be migrated to http://gitlab.freedesktop.org.

To avoid migrating out of date bugs, I am now closing all the bugs that did not see any activity in the past year. If the issue is still happening, please create a new bug in the relevant project at https://gitlab.freedesktop.org/drm (use misc by default).

Sorry about the noise!

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