diff mbox series

[v2,1/1] Documentation: firmware-guide: gpio-properties: Clarify Explicit and Implicit

Message ID 20230213204005.55483-1-andriy.shevchenko@linux.intel.com
State Accepted
Commit 3082d7efd76a55f74f263dc01f059f5b5221e8cc
Headers show
Series [v2,1/1] Documentation: firmware-guide: gpio-properties: Clarify Explicit and Implicit | expand

Commit Message

Andy Shevchenko Feb. 13, 2023, 8:40 p.m. UTC
Clarify the Explicit and Implicit meanings in the table of Pull Bias.

While at it, distinguish pull bias keywords used in ACPI by using bold
font in the table of the respective terms.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
v2: fixed formatting issues
 .../firmware-guide/acpi/gpio-properties.rst   | 35 +++++++++++++------
 1 file changed, 24 insertions(+), 11 deletions(-)

Comments

Rafael J. Wysocki Feb. 14, 2023, 2:51 p.m. UTC | #1
On Mon, Feb 13, 2023 at 9:39 PM Andy Shevchenko
<andriy.shevchenko@linux.intel.com> wrote:
>
> Clarify the Explicit and Implicit meanings in the table of Pull Bias.
>
> While at it, distinguish pull bias keywords used in ACPI by using bold
> font in the table of the respective terms.
>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
> v2: fixed formatting issues
>  .../firmware-guide/acpi/gpio-properties.rst   | 35 +++++++++++++------
>  1 file changed, 24 insertions(+), 11 deletions(-)
>
> 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
> --

Applied as 6.3 material, thanks!
diff mbox series

Patch

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