From 76cb841cb886eef6b3bee341a2266c76578724ad Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Mon, 6 May 2024 03:02:30 +0200 Subject: Adding upstream version 4.19.249. Signed-off-by: Daniel Baumann --- Documentation/arm/Samsung/GPIO.txt | 40 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) create mode 100644 Documentation/arm/Samsung/GPIO.txt (limited to 'Documentation/arm/Samsung/GPIO.txt') diff --git a/Documentation/arm/Samsung/GPIO.txt b/Documentation/arm/Samsung/GPIO.txt new file mode 100644 index 000000000..795adfd88 --- /dev/null +++ b/Documentation/arm/Samsung/GPIO.txt @@ -0,0 +1,40 @@ + Samsung GPIO implementation + =========================== + +Introduction +------------ + +This outlines the Samsung GPIO implementation and the architecture +specific calls provided alongside the drivers/gpio core. + + +S3C24XX (Legacy) +---------------- + +See Documentation/arm/Samsung-S3C24XX/GPIO.txt for more information +about these devices. Their implementation has been brought into line +with the core samsung implementation described in this document. + + +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/plat-samsung/include/plat/gpio-cfg.h for more information +on these functions. -- cgit v1.2.3