Jung-uk Kim <j...@freebsd.org> writes: > On 2013-09-04 09:29:35 -0400, John Baldwin wrote: >> On Tuesday, September 03, 2013 6:58:55 pm Jung-uk Kim wrote: >>> On 2013-09-03 16:47:47 -0400, John Baldwin wrote: >>>> Even with that hacked so I force vgapm0 and dpms0 to attach, I >>>> still can't resume in console mode, ... >>> >>> What happens? Does it panic, hang, or just no backlight? >> >> Just no backlight. It resumes fine and if I do it in multiuser I >> can ssh in, etc. It's just the backlight that doesn't resume. I >> was hopeful dpms.ko would fix that, but it didn't. :( > > Ah, that's a well-known problem and we cannot fix it without help of > machine-specific code, e.g., drm1/drm2. Actually, both acpi_video and > dpms try to restore video settings but nothing worked for Intel GPUs + > LVDS + LCD panel AFAIK. > >> I think i915drm has code to specifically turn on the backlight as >> I get some weird error message in the kernel console about a >> timeout trying to turn the panel off during suspend when I'm in X. > So, I guess it has an ordering issue. If my memory serves, drm1 was > okay with vesa, however. I *think* it accidentally worked because of > automatic VT-switching, which is still broken for KMS.
Yes, perhaps, but there is also the sysctl hw.acpi.reset_video which I have enabled on my older hardware (TP X40 running 8.3-REL and an old Xorg server) for it to work properly. (I however have some faint memory that reset_video might a no-op these days, or?) In this old mail regarding reset_video, there is a thought that it could be good with "more" reinitialisation: http://lists.freebsd.org/pipermail/freebsd-acpi/2006-July/002959.html I however have one datapoint that I think contradicts John's thought. This is on a X201 with stable/9 and no options VESA. I first just booted up and stayed in text console, suspended and resumed. No backlight, of course, and also no content on the LCD, it is completely black. Then, I started Xorg with KMS. Still no backlight, but you can see that the LCD is driven with the desired content, which is one step forward. Finally, I suspended and resumed, but no difference, the backlight is still off. Xorg/KMS didn't manage to turn the backlight on, so the text console suspend/resume cycle managed to persistently turn the backlight off. One more thing, the kernel logs this at resume directly after the devices are powered on (transition to D0), but I have no idea whether it is relevant: Sep 2 19:57:21 bit kernel: error: [drm:pid1904:intel_lvds_enable] *ERROR* timed out waiting for panel to power off Bengt _______________________________________________ freebsd-acpi@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-acpi To unsubscribe, send any mail to "freebsd-acpi-unsubscr...@freebsd.org"
