Documentation: firmware-guide: gpio-properties: Clarify Explicit and Implicit

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>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/Documentation/firmware-guide/acpi/gpio-properties.rst b/Documentation/firmware-guide/acpi/gpio-properties.rst
index eaec732cc77cfdf6674da052b8a3dae266b0af2f..db0c0b1f370081691d1e2b14b7445a677064e5d5 100644 (file)
--- 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