Device (PNLF) {
Name (_ADR, Zero)
Name (_HID, EisaId ("APP0002"))
Name (_CID, "backlight")
Name (_UID, 10)
Name (_STA, 0x0B)
//define hardware register access for brightness
// you can see BAR1 value in RW-Everything under Bus00,02 Intel VGA controler PCI
OperationRegion (BRIT, SystemMemory, \_SB.PCI0.IGPU.BAR1, 0xc8254)
Field (BRIT, AnyAcc, Lock, Preserve)
{
Offset(0x4824c),
LEV2, 32,
LEVL, 32,
Offset (0x7003C),
P0BL, 32,
Offset(0xc824c),
LEVW, 32,
LEVX, 32,
}
Method (_INI, 0, NotSerialized)
{
// If the BIOS actually sets the values prior to boot, this would be
// how (maybe) to capture them. My Envy does not have the capability
// to set brightness and I find these values are not set.
// The current value could also be in LEVL, and probably is even
// though OS X seems to manipulate only the low 16-bits of LEVX to
// change brightness.
// Because the low-order 16-bits are set to zero on the Envy, enabling
// this code causes a blank screen before the login screena appears.
//
//Store(LEVX, Local0)
//Store(ShiftRight(Local0,16), Local1)
//Store(And(Local0,0xFFFF), Local2)
//Divide(Multiply(Local2, 0xad9), Local1, Local0)
//Or(Local0, 0xad90000, Local0)
//
//REVIEW: wait for vblank to change things
//While(LEqual (P0BL, Local1)) {}
//
// This is part of the "keep startup level"...
// see comment above.
//Store(Local0, LEVX)
//
// This 0xC value comes from looking what OS X initializes this
// register to after display sleep (using ACPIDebug/ACPIPoller)
Store(0xC0000000, LEVW)
// Because this laptop starts at full brightness, I just set it right
// here. This is to insure _BQC and XBQC return the correct level
// at startup.
Store(0xad90ad9, LEVX)
}
// _BCM/_BQC: set/get for brightness level
Method (_BCM, 1, NotSerialized)
{
// store new backlight level
Store(Match(_BCL, MGE, Arg0, MTR, 0, 2), Local0)
If (LEqual(Local0, Ones)) { Subtract(SizeOf(_BCL), 1, Local0) }
Store(Or(DerefOf(Index(_BCL,Local0)),And(LEVX,0xFFFF0000)), LEVX)
}
Method (_BQC, 0, NotSerialized)
{
Store(Match(_BCL, MGE, And(LEVX, 0xFFFF), MTR, 0, 2), Local0)
If (LEqual(Local0, Ones)) { Subtract(SizeOf(_BCL), 1, Local0) }
Return(DerefOf(Index(_BCL, Local0)))
}
Method (_DOS, 1, NotSerialized)
{
^^PCI0.IGPU._DOS(Arg0)
}
// extended _BCM/_BQC for setting "in between" levels
Method (XBCM, 1, NotSerialized)
{
// store new backlight level
If (LGreater(Arg0, XRGH)) { Store(XRGH, Arg0) }
If (LAnd(Arg0, LLess(Arg0, XRGL))) { Store(XRGL, Arg0) }
Store(Or(Arg0,And(LEVX,0xFFFF0000)), LEVX)
}
Method (XBQC, 0, NotSerialized)
{
Store(And(LEVX,0xFFFF), Local0)
If (LGreater(Local0, XRGH)) { Store(XRGH, Local0) }
If (LAnd(Local0, LLess(Local0, XRGL))) { Store(XRGL, Local0) }
Return(Local0)
}
// Use XOPT=1 to disable smooth transitions
Name (XOPT, Zero)
// XRGL/XRGH: defines the valid range
Name (XRGL, 1)
Name (XRGH, 1400)
// _BCL: returns list of valid brightness levels
// first two entries describe ac/battery power levels
Name (_BCL, Package()
{
780,
320,
0,
2, 4, 6, 9,
12, 15, 19, 23,
27, 32, 37, 42,
48, 54, 60, 67,
74, 82, 90, 99,
108, 118, 130, 143,
157, 172, 188, 205,
223, 242, 262, 283,
305, 328, 352, 377,
403, 430, 458, 487,
517, 547, 577, 609,
641, 674, 708, 743,
779, 810, 845, 880,
915, 950, 985, 1020,
1055, 1095, 1140, 1190,
1240, 1290, 1340, 1400,
})
}
