Bug 15850

Summary: Switcheroo: LVDS on radeon not working after suspend
Product: Drivers Reporter: Michał Witkowski (neuro)
Component: Video(DRI - non Intel)Assignee: drivers_video-dri
Severity: normal CC: alan
Priority: P1    
Hardware: All   
OS: Linux   
Kernel Version: 2.6.34-rc4 Tree: Mainline
Regression: No
Attachments: Dmesg after resume with not working LVDS

Description Michał Witkowski 2010-04-25 20:37:29 UTC
Created attachment 26139 [details]
Dmesg after resume with not working LVDS

Lenovo Ideapad U330 with Radeon 3450 and Intel 4500MHD
Arch Linux current with kernel 2.6.34-rc4 (+switchable graphics).

LVDS doesn't come back after suspend while HDMI does with or without X server.

Ways to reproduce:
1. Start into console (init 3)
2. Load modules in this order: i915, radeon, fbcom
3. cat DDIS > $STATE
4. pm-suspend
5. Press any key to resume the system
8. *bam*. LVDS is off (backlight is off, no garbage, no cursor) and HDMI works.

1. Before using switchable graphics (in Discrete only BIOS setting) suspend resumed cleanly in X and in console.
2. I guess this might have something to do with the order I'm loading the modules
2. My guess is: radeon tries to bring up only LVDS-0 and not LVDS-1. After switcheroo, my LVDS is named LVDS-1 in radeon and LVDS-0 in intel, regardless of which one is used. HDMI is only available in radeon as HDMI-0 and it gets resumed.

Will attach dmesg.