mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-24 05:04:00 +08:00
d192baeaa7
Add some documentation in Documentation/arm/Samsung for the GPIO code and where to look for the necessary functions. Update the S3C24XX case as well. Signed-off-by: Ben Dooks <ben-linux@fluff.org>
43 lines
1.2 KiB
Plaintext
43 lines
1.2 KiB
Plaintext
Samsung GPIO implementation
|
|
===========================
|
|
|
|
Introduction
|
|
------------
|
|
|
|
This outlines the Samsung GPIO implementation and the architecture
|
|
specfic calls provided alongisde the drivers/gpio core.
|
|
|
|
|
|
S3C24XX (Legacy)
|
|
----------------
|
|
|
|
See Documentation/arm/Samsung-S3C24XX/GPIO.txt for more information
|
|
about these devices. Their implementation is being 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 architecutre, 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.
|
|
|
|
|