diff options
| -rw-r--r-- | src/drivers/intel/gma/acpi/configure_brightness_levels.asl | 87 |
1 files changed, 36 insertions, 51 deletions
diff --git a/src/drivers/intel/gma/acpi/configure_brightness_levels.asl b/src/drivers/intel/gma/acpi/configure_brightness_levels.asl index 01642ddc6b..dfd878cb26 100644 --- a/src/drivers/intel/gma/acpi/configure_brightness_levels.asl +++ b/src/drivers/intel/gma/acpi/configure_brightness_levels.asl @@ -98,36 +98,6 @@ Return (Ones) } - - /* - * Get current back-light brightness through mailbox 3 - * - * @Return The current brightness or Ones on error - * Errors: * ASLS is zero - * * Mailbox 3 support not advertised - * * Driver not loaded or not ready - * * CBLV is not marked valid - */ - Method (XBQC, 0, NotSerialized) - { - If (LEqual(ASLS, Zero)) - { - Return (Ones) - } - If (LEqual(And(MBOX, 0x4), Zero)) - { - Return (Ones) - } - If (LEqual(ARDY, Zero)) - { - Return (Ones) - } - If (LEqual(And (CBLV, 0x80000000), Zero)) - { - Return (Ones) - } - Return (And (CBLV, 0xff)) - } } /* @@ -137,29 +107,45 @@ { Name (_ADR, 0) + /* Divide round closest */ + Method (DRCL, 2) + { + Return (Divide (Add (Arg0, Divide (Arg1, 2)), Arg1)) + } + Method (XBCM, 1, NotSerialized) { - Store (Divide (Multiply (Arg0, BCLM), 100), BCLV) + Store (DRCL (Multiply (Arg0, BCLM), 100), BCLV) } + /* Find value closest to BCLV in BRIG (which must be ordered) */ Method (XBQC, 0, NotSerialized) { - /* Find value close to BCLV in BRIG (which must be ordered) */ - Store (BCLV, Local0) // Current value - Store (BCLM, Local1) // For calculations - Store (2, Local2) // Loop index - While (LLess (Local2, Subtract (SizeOf (BRIG), 1))) { - Store (DeRefOf (Index (BRIG, Local2)), Local3) - /* Use same calculation as XBCM, to get exact matches */ - Store (Divide (Multiply (Local3, Local1), 100), Local3) - - If (LLessEqual (Local0, Local3)) { - Return (DeRefOf (Index (BRIG, Local2))) + /* Local0: current percentage */ + Store (DRCL (Multiply (BCLV, 100), BCLM), Local0) + + /* Local1: loop index (selectable values start at 2 in BRIG) */ + Store (2, Local1) + While (LLess (Local1, Subtract (SizeOf (BRIG), 1))) { + /* Local[23]: adjacent values in BRIG */ + Store (DeRefOf (Index (BRIG, Local1)), Local2) + Store (DeRefOf (Index (BRIG, Add (Local1, 1))), Local3) + + If (LLess (Local0, Local3)) { + If (LOr (LLess (Local0, Local2), + LLess (Subtract (Local0, Local2), + Subtract (Local3, Local0)))) { + Return (Local2) + } Else { + Return (Local3) + } } - Add (Local2, 1, Local2) + + Increment (Local1) } + /* Didn't find greater/equal value: use the last */ - Return (DeRefOf (Index (BRIG, Local2))) + Return (Local3) } } @@ -173,11 +159,10 @@ Method (XBQC, 0, NotSerialized) { - Store (^BOX3.XBQC (), Local0) - If (LEqual(Local0, Ones)) - { - Store (^LEGA.XBQC (), Local0) - } - - Return (Local0) + /* + * Always query the hardware directly. Not all OS drivers + * keep CBLV up to date (one is Linux' i915). Some years + * after that is fixed we can probably use CBLV? + */ + Return (^LEGA.XBQC ()) } |