diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/firmware-guide/acpi/acpi-lid.rst | 2 | ||||
| -rw-r--r-- | Documentation/firmware-guide/acpi/gpio-properties.rst | 35 | ||||
| -rw-r--r-- | Documentation/firmware-guide/acpi/namespace.rst | 2 |
3 files changed, 26 insertions, 13 deletions
diff --git a/Documentation/firmware-guide/acpi/acpi-lid.rst b/Documentation/firmware-guide/acpi/acpi-lid.rst index 71b9af13a048..03cbad6c6730 100644 --- a/Documentation/firmware-guide/acpi/acpi-lid.rst +++ b/Documentation/firmware-guide/acpi/acpi-lid.rst @@ -34,7 +34,7 @@ state upon the last _LID evaluation. There won't be difference when the _LID control method is evaluated during the runtime, the problem is its initial returning value. When the AML tables implement this control method with cached value, the initial returning value is likely not reliable. -There are platforms always retun "closed" as initial lid state. +There are platforms always return "closed" as initial lid state. Restrictions of the lid state change notifications ================================================== diff --git a/Documentation/firmware-guide/acpi/gpio-properties.rst b/Documentation/firmware-guide/acpi/gpio-properties.rst index eaec732cc77c..db0c0b1f3700 100644 --- a/Documentation/firmware-guide/acpi/gpio-properties.rst +++ b/Documentation/firmware-guide/acpi/gpio-properties.rst @@ -67,17 +67,30 @@ state of the output pin which driver should use during its initialization. Linux tries to use common sense here and derives the state from the bias and polarity settings. The table below shows the expectations: -========= ============= ============== -Pull Bias Polarity Requested... -========= ============= ============== -Implicit x AS IS (assumed firmware configured for us) -Explicit x (no _DSD) as Pull Bias (Up == High, Down == Low), - assuming non-active (Polarity = !Pull Bias) -Down Low as low, assuming active -Down High as low, assuming non-active -Up Low as high, assuming non-active -Up High as high, assuming active -========= ============= ============== ++-------------+-------------+-----------------------------------------------+ +| Pull Bias | Polarity | Requested... | ++=============+=============+===============================================+ +| Implicit | ++-------------+-------------+-----------------------------------------------+ +| **Default** | x | AS IS (assumed firmware configured it for us) | ++-------------+-------------+-----------------------------------------------+ +| Explicit | ++-------------+-------------+-----------------------------------------------+ +| **None** | x | AS IS (assumed firmware configured it for us) | +| | | with no Pull Bias | ++-------------+-------------+-----------------------------------------------+ +| **Up** | x (no _DSD) | | +| +-------------+ as high, assuming non-active | +| | Low | | +| +-------------+-----------------------------------------------+ +| | High | as high, assuming active | ++-------------+-------------+-----------------------------------------------+ +| **Down** | x (no _DSD) | | +| +-------------+ as low, assuming non-active | +| | High | | +| +-------------+-----------------------------------------------+ +| | Low | as low, assuming active | ++-------------+-------------+-----------------------------------------------+ That said, for our above example the both GPIOs, since the bias setting is explicit and _DSD is present, will be treated as active with a high diff --git a/Documentation/firmware-guide/acpi/namespace.rst b/Documentation/firmware-guide/acpi/namespace.rst index 6193582a2204..4ef963679a3d 100644 --- a/Documentation/firmware-guide/acpi/namespace.rst +++ b/Documentation/firmware-guide/acpi/namespace.rst @@ -31,7 +31,7 @@ Description Table). The XSDT always points to the FADT (Fixed ACPI Description Table) using its first entry, the data within the FADT includes various fixed-length entries that describe fixed ACPI features of the hardware. The FADT contains a pointer to the DSDT -(Differentiated System Descripition Table). The XSDT also contains +(Differentiated System Description Table). The XSDT also contains entries pointing to possibly multiple SSDTs (Secondary System Description Table). |