1 Samsung GPIO implementation 2 =========================== 3 4Introduction 5------------ 6 7This outlines the Samsung GPIO implementation and the architecture 8specfic calls provided alongisde the drivers/gpio core. 9 10 11S3C24XX (Legacy) 12---------------- 13 14See Documentation/arm/Samsung-S3C24XX/GPIO.txt for more information 15about these devices. Their implementation is being brought into line 16with the core samsung implementation described in this document. 17 18 19GPIOLIB integration 20------------------- 21 22The gpio implementation uses gpiolib as much as possible, only providing 23specific calls for the items that require Samsung specific handling, such 24as pin special-function or pull resistor control. 25 26GPIO numbering is synchronised between the Samsung and gpiolib system. 27 28 29PIN configuration 30----------------- 31 32Pin configuration is specific to the Samsung architecutre, with each SoC 33registering the necessary information for the core gpio configuration 34implementation to configure pins as necessary. 35 36The s3c_gpio_cfgpin() and s3c_gpio_setpull() provide the means for a 37driver or machine to change gpio configuration. 38 39See arch/arm/plat-samsung/include/plat/gpio-cfg.h for more information 40on these functions. 41 42 43