Workaround for buggy vendor backlight implements

[zhen-zen]

Yesterday I was notified for another exception.

The structure is:

GFX0@20000
- DD01@100
- DD02@2
- DD03@300
- DD04@301
- DD05@5
- DD06@6
- DD07@7
- DD08@8
- DD09@9
- DD0A@a
- DD0B@b
- DD0C@c
- DD0D@d
- DD0E@e
- DD0F@f
- DD1F@410

Which is quite similar to my desktop one

GFX0@20000
- DD01@100
- DD02@2
- DD03@300
- DD04@301
- DD05@302
- DD06@6
- DD07@7
- DD08@8
- DD09@9
- DD0A@a
- DD0B@b
- DD0C@c
- DD0D@d
- DD0E@e
- DD0F@f
- DD1F@1f

I added a mask to verify bit [11:8] for display type. However, later I was told DD02 was actually notified.

        Method (_Q1C, 0, NotSerialized)  // _Qxx: EC Query, xx=0x00-0xFF
        {
            P80H = 0x1C
            BCEN = Zero
            BCVE = Zero
            If (QWIK) // non-zero
            {
                Notify (^^^GFX0.DD02, 0x86) // Device-Specific
            }
            ElseIf (BCEN)
            {
                If (BCVE)
                {
                    If ((^^^GFX0.IGID != 0xFFFF))
                    {
                        ^^^GFX0.SPBR (BNVA, Zero)
                    }
                }

                LAMN (0x73)
            }
            Else
            {
                Acquire (MSGF, 0xFFFF)
                If ((^^^GFX0.IGID != 0xFFFF))
                {
                    BIAN (0x86) // will notify DD1F correctly
                }

                Release (MSGF)
            }
        }

The result didn't follow the spec as well. I suppose it's a mis-configuration that route to obsolete DD02 again.

I didn't come up with some good idea to identify that. So maybe it could be handled by additional fallback notifier?

[zhen-zen]

For discrete one: newer systems don't use the 0x110 Legacy Panel for address. Instead, they could export the display type per specs, e.g. 0x8000a450.

Related notification also changed:

            Method (_Q14, 0, NotSerialized)  // _Qxx: EC Query, xx=0x00-0xFF
            {
                If (\_SB.PCI0.LPC.EC.HKEY.MHKK (0x8000))
                {
                    \_SB.PCI0.LPC.EC.HKEY.MHKQ (0x1010)
                }

                If (\NBCF)
                {
                    If (\VIGD)
                    {
                        Notify (\_SB.PCI0.VID.LCD0, 0x86) // Device-Specific
                    }
                    Else
                    {
                        Notify (\_SB.PCI0.PEG.VID.LCD0, 0x86) // Device-Specific
                    }
                }
                Else
                {
                    Local0 = \BRLV
                    If ((Local0 != 0x0F))
                    {
                        Local0++
                        \BRLV = Local0
                    }

                    If (\VIGD)
                    {
                        \UCMS (0x16)
                        \_SB.PCI0.LPC.EC.BRNS ()
                    }
                    Else
                    {
                        \VBRC (Local0)
                    }

                    \_SB.PCI0.LPC.EC.HKEY.MHKQ (0x6050)
                }
            }

Although I suppose discrete AMD graphics has disappeared for a long time, the separate notifiers might not break things such as duplicate notification. And graphics hot switch also seems impossible.