1=========================== 2Samsung GPIO implementation 3=========================== 4 5Introduction 6------------ 7 8This outlines the Samsung GPIO implementation and the architecture 9specific calls provided alongside the drivers/gpio core. 10 11 12S3C24XX (Legacy) 13---------------- 14 15See Documentation/arm/samsung-s3c24xx/gpio.rst for more information 16about these devices. Their implementation has been brought into line 17with the core samsung implementation described in this document. 18 19 20GPIOLIB integration 21------------------- 22 23The gpio implementation uses gpiolib as much as possible, only providing 24specific calls for the items that require Samsung specific handling, such 25as pin special-function or pull resistor control. 26 27GPIO numbering is synchronised between the Samsung and gpiolib system. 28 29 30PIN configuration 31----------------- 32 33Pin configuration is specific to the Samsung architecture, with each SoC 34registering the necessary information for the core gpio configuration 35implementation to configure pins as necessary. 36 37The s3c_gpio_cfgpin() and s3c_gpio_setpull() provide the means for a 38driver or machine to change gpio configuration. 39 40See arch/arm/mach-s3c/gpio-cfg.h for more information on these functions. 41