On Tue, Jul 30, 2013 at 9:22 PM, Aaron Lu <aaron.lwe@xxxxxxxxx> wrote: > On 07/31/2013 10:07 AM, Felipe Contreras wrote: >> On Tue, Jul 30, 2013 at 8:36 PM, Aaron Lu <aaron.lwe@xxxxxxxxx> wrote: >>> On 07/31/2013 08:11 AM, Felipe Contreras wrote: >>>> On Tue, Jul 30, 2013 at 6:13 PM, Rafael J. Wysocki <rjw@xxxxxxx> wrote: >>>>> Yes, that will break backlight on your system and *then* you can complain to >>>>> Linus if you wish. >>>> >>>> It is already broken in v3.11-rc3, in fact I just booted that to try >>>> it out and it booted with the screen completely black (fortunately I >>>> knew exactly what to type to change that). >>> >>> That is bad, can you please file a bug for that? I'll need to take a >>> look at your ACPI tables, thanks. >> >> File a bug where? > > https://bugzilla.kernel.org/ > For component, please choose ACPI->Power_Video. Here you go: https://bugzilla.kernel.org/show_bug.cgi?id=60677 >>>> Apparently this commit also needs to be reverted: efaa14c (ACPI / >>>> video: no automatic brightness changes by win8-compatible firmware). >>>> In this machine it makes the backlight work again (without >>>> acpi_osi="!Windows 2012"), but by doing so the ACPI driver also turns >>>> off the screen completely at level 0. Also, each time I change the >>> >>> So with rc3 and commit efaa14c reverted, when you set level 0 to ACPI >>> video's backlight interface, the screen will be off now? And this is not >>> the case in 3.10, right? >> >> No, setting level 0 turns it off if efaa14c is *not* reverted. In 3.10 >> 0 doesn't turn it off. > > AFAIK, Win8 firmware will check a flag to decide what to do on hotkey > press and backlight brightness level change. Common behavior is: > If that flag is set: > - on hotkey press, send out event; > - on brightness level change, use GPU driver's interface to change > backlight level following operation region spec. > If that flag is not set: > - on hotkey press, adjust the brightness level without sending out > event; > - on brightness level change, use EC to change the brightness level. > > The said commit sets the flag, so it seems with the flag set now, > it is possible the firmware interface will also give a screen off > result. But since we want to have notification event, we will have to > set that flag I think. Probably, but changing the brightness should still work even without the flag, right? It doesn't work here. Setting the flag makes it work, but not properly. >>> Please attach acpidump output to the to be opened bugzilla page, thanks. >> >> I looked at the code in the DCDT, it appears to me that they store >> different levels depending on the OSI version, so I don't think the >> problem is in the ACPI driver. Yet, the issue remains there. > > It's good to know what is the problem, so I would like to see the table. > Most of the bugs I solved in ACPI video driver's backlight control are > caused by firmware, so yes, it's very unlikely a bug of the ACPI video > driver itself. I hope you meant the output of this: https://aur.archlinux.org/packages/acpidump/ -- Felipe Contreras -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
