Hi,
On Tue, Apr 11, 2017 at 03:31:34PM -0400, João Paulo Rechi Vita wrote:
> Hello,
>
> I'm working to support the status LEDs embedded in the "mic mute" and
> "radio toggle" buttons on a Acer TravelMate P648-G2-MG laptop, but
> can't quite get how these are controlled. I have traced the ACPI
> execution from Windows for both buttons, and tried to compare with a
> method tracing on Linux, but couldn't get much out of it.
>
> For the mic mute button, I see _Q45, WMID._WED, WMID.EVBC and
> WMID.CLBC being called on both platforms. For the radios button, I see
I simply checked the code path of _Q45 and EVBC. The logic in EVBC is
controlled by EC:
ssdt11.dsl
Method (EVBC, 0, Serialized) /* called by _WED */
{
Local0 = DerefOf (FEBC [Zero])
Switch (Local0)
{
Case (One) /* case One is set in _Q45 */
{
CLBC (0x04, 0x04)
Local1 = DerefOf (FEBC [One]) /* FEBC [One] set to HTBN by _Q45, HTBN = 0x4a on Windows */
Local2 = Zero
...
The HTBN is in the EC memory space:
dsdt.dsl
Device (EC0)
{
Name (_HID, EisaId ("PNP0C09") /* Embedded Controller Device */) // _HID: Hardware ID
Name (_GPE, 0x50) // _GPE: General Purpose Events
Name (OKEC, One)
...
OperationRegion (ECMM, SystemMemory, 0xFF000800, 0x1000)
Field (ECMM, AnyAcc, Lock, Preserve)
{
CDPR, 1,
LCDS, 1,
, 5,
ISEN, 1,
HTBN, 8,
...
>From your debugger log, the HTBN is 0x4a on windows:
ffff9f0d3f8dde53: | Store(HTBN=0x4a,Index(^^^WMID.FEBC=Buffer(0x8){
So, EVBC runs into the path to set 0x02 and 0x03 of FEBC and return
FEBC to _WED:
Method (EVBC, 0, Serialized)
{
Local0 = DerefOf (FEBC [Zero])
Switch (Local0)
{
Case (One)
{
CLBC (0x04, 0x04)
Local1 = DerefOf (FEBC [One])
Local2 = Zero
If (((Local1 > Zero) && (Local1 < 0x20)))
{
...
ElseIf (((Local1 > 0x80) && (Local1 < 0xA0)))
...
Else /* 0x4a */
{
FEBC [0x02] = Zero
FEBC [0x03] = Zero
}
...
Return (FEBC) /* \_SB_.PCI0.WMID.FEBC */
}
The point is what the HTBN value on Linux. I am not familiar with EC
logic. Sorry for can not give you too many help.
Thanks a lot!
Joey Lee
