Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 32 insertions, 0 deletions

diff --git a/Documentation/arch/arm/samsung/gpio.rst b/Documentation/arch/arm/samsung/gpio.rst
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+===========================
+Samsung GPIO implementation
+===========================
+
+Introduction
+------------
+
+This outlines the Samsung GPIO implementation and the architecture
+specific calls provided alongside the drivers/gpio core.
+
+
+GPIOLIB integration
+-------------------
+
+The gpio implementation uses gpiolib as much as possible, only providing
+specific calls for the items that require Samsung specific handling, such
+as pin special-function or pull resistor control.
+
+GPIO numbering is synchronised between the Samsung and gpiolib system.
+
+
+PIN configuration
+-----------------
+
+Pin configuration is specific to the Samsung architecture, with each SoC
+registering the necessary information for the core gpio configuration
+implementation to configure pins as necessary.
+
+The s3c_gpio_cfgpin() and s3c_gpio_setpull() provide the means for a
+driver or machine to change gpio configuration.
+
+See arch/arm/mach-s3c/gpio-cfg.h for more information on these functions.