https://bugzilla.kernel.org/show_bug.cgi?id=36322
--- Comment #13 from Lee, Chun-Yi <j...@novell.com> 2011-06-03 08:16:10 --- It's a great hack. Could you please also try acpi_osi="!Windows 2009"? maybe it also work like acpi_osi="Linux"? --- Comment #14 from Lee, Chun-Yi <j...@novell.com> 2011-06-03 08:51:25 --- (In reply to comment #12) > I did some reverse engineering and trying. Here are my results and some > thoughts: > Thank's for your great hacker. > Calling _SB.PCI0.LPCB.EC0.BRXP "activates" the brightness which is set > in the BLVL. > > The DSDT contains this code three times: > > If (LAnd (LLess (OSYS, 0x07D6), LEqual (SGST, Zero))) > { > BRXP () > } Else { > ... > } > > OSYS on my machine is 0x07D9 ("Windows 2009"), while there is 0x03E8 ("Linux") > available in the os setup (_INI). > SGST, whatever that may be, is currently 0. > Could you please also try acpi_osi"!Windows 2009" ? > Method (BRXP, 0, NotSerialized) > { > Multiply (DerefOf (Index (PNLT, BLVL)), 0x64, Local1) > Divide (Local1, 0x0100, , Local2) > ^^^GFX0.AINT (One, Local2) > } > > So let's look for AINT. Only BRXP calls this method. > > AINT, stripped down, is: > PARD() > Store (Divide (Multiply (Arg1, 0xFF), 0x64, ), BCLP) > Or (BCLP, 0x80000000, BCLP) > Store (0x02, ASLC) > Store (One, ASLE) > The AINT is the mathod the control the backlight base on Intel OpRegion spec. > > I still don't know the correct way to set the brightness. > * Use the "Linux" OSYS? It can fix the brightness control problem on your machine, but conflict with current kernel acpi strategy: bit newest windows version (Windows 7) > * Call BRXP after each change to the brightness? > * Call ISBC? This would be cool because you don't have 10 but 256 different > states. I thought it's too specifically and I cann't direct evaluate a special acpi method in acer-wmi. On the other hand, Per Windows 7 path, DSDT follow standard acpi way, brightness control must handle by acpi/video.c but not in acer-wmi : _Q8E/_Q8F -> Nodify GFX0.DD02 -> acpi/video.c -> evaluation _BCM -> LPCB.EC0.BLVL > > I hope that this helps you with updating the driver. I still want to know what _REAL_ way acer doing in Windows7, then we need find a way to do the same thing with Windows7. I don't thing they direct access BRXP in their driver, it's very dirty. -- Configure bugmail: https://bugzilla.kernel.org/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are watching the assignee of the bug. ------------------------------------------------------------------------------ Simplify data backup and recovery for your virtual environment with vRanger. Installation's a snap, and flexible recovery options mean your data is safe, secure and there when you need it. Discover what all the cheering's about. Get your free trial download today. http://p.sf.net/sfu/quest-dev2dev2 _______________________________________________ acpi-bugzilla mailing list acpi-bugzilla@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/acpi-bugzilla