41 lines
1.2 KiB
Plaintext
41 lines
1.2 KiB
Plaintext
|
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.
|